Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

104 files changed, 10081 insertions, 0 deletions

diff --git a/arch/nios2/Kbuild b/arch/nios2/Kbuild
new file mode 100644
index 000000000..fc2952edd
--- /dev/null
+++ b/arch/nios2/Kbuild
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-y += kernel/ mm/ platform/ boot/dts/
+
+# for cleaning
+subdir- += boot
diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
new file mode 100644
index 000000000..1fb78865a
--- /dev/null
+++ b/arch/nios2/Kconfig
@@ -0,0 +1,182 @@
+# SPDX-License-Identifier: GPL-2.0
+config NIOS2
+	def_bool y
+	select ARCH_32BIT_OFF_T
+	select ARCH_HAS_DMA_PREP_COHERENT
+	select ARCH_HAS_SYNC_DMA_FOR_CPU
+	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
+	select ARCH_HAS_DMA_SET_UNCACHED
+	select ARCH_NO_SWAP
+	select COMMON_CLK
+	select TIMER_OF
+	select GENERIC_ATOMIC64
+	select GENERIC_CPU_DEVICES
+	select GENERIC_IRQ_PROBE
+	select GENERIC_IRQ_SHOW
+	select HAVE_ARCH_TRACEHOOK
+	select HAVE_ARCH_KGDB
+	select IRQ_DOMAIN
+	select LOCK_MM_AND_FIND_VMA
+	select MODULES_USE_ELF_RELA
+	select OF
+	select OF_EARLY_FLATTREE
+	select SOC_BUS
+	select SPARSE_IRQ
+	select USB_ARCH_HAS_HCD if USB_SUPPORT
+	select CPU_NO_EFFICIENT_FFS
+	select MMU_GATHER_NO_RANGE if MMU
+
+config GENERIC_CSUM
+	def_bool y
+
+config GENERIC_HWEIGHT
+	def_bool y
+
+config GENERIC_CALIBRATE_DELAY
+	def_bool y
+
+config NO_IOPORT_MAP
+	def_bool y
+
+config FPU
+	def_bool n
+
+menu "Kernel features"
+
+source "kernel/Kconfig.hz"
+
+config ARCH_FORCE_MAX_ORDER
+	int "Maximum zone order"
+	range 9 20
+	default "11"
+	help
+	  The kernel memory allocator divides physically contiguous memory
+	  blocks into "zones", where each zone is a power of two number of
+	  pages.  This option selects the largest power of two that the kernel
+	  keeps in the memory allocator.  If you need to allocate very large
+	  blocks of physically contiguous memory, then you may need to
+	  increase this value.
+
+	  This config option is actually maximum order plus one. For example,
+	  a value of 11 means that the largest free memory block is 2^10 pages.
+
+endmenu
+
+source "arch/nios2/platform/Kconfig.platform"
+
+menu "Processor type and features"
+
+config MMU
+	def_bool y
+
+config NR_CPUS
+	int
+	default "1"
+
+config NIOS2_ALIGNMENT_TRAP
+	bool "Catch alignment trap"
+	default y
+	help
+	  Nios II CPUs cannot fetch/store data which is not bus aligned,
+	  i.e., a 2 or 4 byte fetch must start at an address divisible by
+	  2 or 4. Any non-aligned load/store instructions will be trapped and
+	  emulated in software if you say Y here, which has a performance
+	  impact.
+
+comment "Boot options"
+
+config CMDLINE_BOOL
+	bool "Default bootloader kernel arguments"
+	default y
+
+config CMDLINE
+	string "Default kernel command string"
+	default ""
+	depends on CMDLINE_BOOL
+	help
+	  On some platforms, there is currently no way for the boot loader to
+	  pass arguments to the kernel. For these platforms, you can supply
+	  some command-line options at build time by entering them here.  In
+	  other cases you can specify kernel args so that you don't have
+	  to set them up in board prom initialization routines.
+
+config CMDLINE_FORCE
+	bool "Force default kernel command string"
+	depends on CMDLINE_BOOL
+	help
+	  Set this to have arguments from the default kernel command string
+	  override those passed by the boot loader.
+
+config NIOS2_CMDLINE_IGNORE_DTB
+	bool "Ignore kernel command string from DTB"
+	depends on CMDLINE_BOOL
+	depends on !CMDLINE_FORCE
+	default y
+	help
+	  Set this to ignore the bootargs property from the devicetree's
+	  chosen node and fall back to CMDLINE if nothing is passed.
+
+config NIOS2_PASS_CMDLINE
+	bool "Passed kernel command line from u-boot"
+	help
+	  Use bootargs env variable from u-boot for kernel command line.
+	  will override "Default kernel command string".
+	  Say N if you are unsure.
+
+config NIOS2_BOOT_LINK_OFFSET
+	hex "Link address offset for booting"
+	default "0x00500000"
+	help
+	  This option allows you to set the link address offset of the zImage.
+	  This can be useful if you are on a board which has a small amount of
+	  memory.
+
+endmenu
+
+menu "Advanced setup"
+
+config ADVANCED_OPTIONS
+	bool "Prompt for advanced kernel configuration options"
+
+comment "Default settings for advanced configuration options are used"
+	depends on !ADVANCED_OPTIONS
+
+config NIOS2_KERNEL_MMU_REGION_BASE_BOOL
+	bool "Set custom kernel MMU region base address"
+	depends on ADVANCED_OPTIONS
+	help
+	  This option allows you to set the virtual address of the kernel MMU region.
+
+	  Say N here unless you know what you are doing.
+
+config NIOS2_KERNEL_MMU_REGION_BASE
+	hex "Virtual base address of the kernel MMU region " if NIOS2_KERNEL_MMU_REGION_BASE_BOOL
+	default "0x80000000"
+	help
+	  This option allows you to set the virtual base address of the kernel MMU region.
+
+config NIOS2_KERNEL_REGION_BASE_BOOL
+	bool "Set custom kernel region base address"
+	depends on ADVANCED_OPTIONS
+	help
+	  This option allows you to set the virtual address of the kernel region.
+
+	  Say N here unless you know what you are doing.
+
+config NIOS2_KERNEL_REGION_BASE
+	hex "Virtual base address of the kernel region " if NIOS2_KERNEL_REGION_BASE_BOOL
+	default "0xc0000000"
+
+config NIOS2_IO_REGION_BASE_BOOL
+	bool "Set custom I/O region base address"
+	depends on ADVANCED_OPTIONS
+	help
+	  This option allows you to set the virtual address of the I/O region.
+
+	  Say N here unless you know what you are doing.
+
+config NIOS2_IO_REGION_BASE
+	hex "Virtual base address of the I/O region" if NIOS2_IO_REGION_BASE_BOOL
+	default "0xe0000000"
+
+endmenu
diff --git a/arch/nios2/Kconfig.debug b/arch/nios2/Kconfig.debug
new file mode 100644
index 000000000..ca1beb87f
--- /dev/null
+++ b/arch/nios2/Kconfig.debug
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config EARLY_PRINTK
+	bool "Activate early kernel debugging"
+	default y
+	depends on TTY
+	select SERIAL_CORE_CONSOLE
+	help
+	  Enable early printk on console.
+	  This is useful for kernel debugging when your machine crashes very
+	  early before the console code is initialized.
+	  You should normally say N here, unless you want to debug such a crash.
diff --git a/arch/nios2/Makefile b/arch/nios2/Makefile
new file mode 100644
index 000000000..f1ff4ce0f
--- /dev/null
+++ b/arch/nios2/Makefile
@@ -0,0 +1,62 @@
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (C) 2013 Altera Corporation
+# Copyright (C) 1994, 95, 96, 2003 by Wind River Systems
+# Written by Fredrik Markstrom
+#
+# This file is included by the global makefile so that you can add your own
+# architecture-specific flags and dependencies.
+#
+# Nios2 port by Wind River Systems Inc trough:
+#   fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+
+KBUILD_DEFCONFIG := 3c120_defconfig
+
+UTS_SYSNAME = Linux
+
+export MMU
+
+LIBGCC         := $(shell $(CC) $(KBUILD_CFLAGS) $(KCFLAGS) -print-libgcc-file-name)
+
+KBUILD_AFLAGS += -march=r$(CONFIG_NIOS2_ARCH_REVISION)
+
+KBUILD_CFLAGS += -pipe -D__linux__ -D__ELF__
+KBUILD_CFLAGS += -march=r$(CONFIG_NIOS2_ARCH_REVISION)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_HW_MUL_SUPPORT),-mhw-mul,-mno-hw-mul)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_HW_MULX_SUPPORT),-mhw-mulx,-mno-hw-mulx)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_HW_DIV_SUPPORT),-mhw-div,-mno-hw-div)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_BMX_SUPPORT),-mbmx,-mno-bmx)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_CDX_SUPPORT),-mcdx,-mno-cdx)
+KBUILD_CFLAGS += $(if $(CONFIG_NIOS2_FPU_SUPPORT),-mcustom-fpu-cfg=60-1,)
+
+KBUILD_CFLAGS += -fno-optimize-sibling-calls
+KBUILD_CFLAGS += -DUTS_SYSNAME=\"$(UTS_SYSNAME)\"
+KBUILD_CFLAGS += -fno-builtin
+KBUILD_CFLAGS += -G 0
+
+libs-y		+= arch/nios2/lib/ $(LIBGCC)
+
+INSTALL_PATH ?= /tftpboot
+nios2-boot := arch/$(ARCH)/boot
+BOOT_TARGETS = vmImage zImage
+PHONY += $(BOOT_TARGETS) install
+KBUILD_IMAGE := $(nios2-boot)/vmImage
+
+all: vmImage
+
+$(BOOT_TARGETS): vmlinux
+	$(Q)$(MAKE) $(build)=$(nios2-boot) $(nios2-boot)/$@
+
+install:
+	$(call cmd,install)
+
+define archhelp
+  echo  '* vmImage         - Kernel-only image for U-Boot ($(KBUILD_IMAGE))'
+  echo  '  install         - Install kernel using'
+  echo  '                     (your) ~/bin/$(INSTALLKERNEL) or'
+  echo  '                     (distribution) /sbin/$(INSTALLKERNEL) or'
+  echo  '                     install to $$(INSTALL_PATH)'
+endef
diff --git a/arch/nios2/boot/.gitignore b/arch/nios2/boot/.gitignore
new file mode 100644
index 000000000..ef37cac5b
--- /dev/null
+++ b/arch/nios2/boot/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vmImage
diff --git a/arch/nios2/boot/Makefile b/arch/nios2/boot/Makefile
new file mode 100644
index 000000000..29c11a06b
--- /dev/null
+++ b/arch/nios2/boot/Makefile
@@ -0,0 +1,32 @@
+#
+# arch/nios2/boot/Makefile
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+
+UIMAGE_LOADADDR = $(shell $(NM) vmlinux | awk '$$NF == "_stext" {print $$1}')
+UIMAGE_ENTRYADDR = $(shell $(NM) vmlinux | awk '$$NF == "_start" {print $$1}')
+UIMAGE_COMPRESSION = gzip
+
+OBJCOPYFLAGS_vmlinux.bin := -O binary
+
+targets += vmlinux.bin vmlinux.gz vmImage
+
+$(obj)/vmlinux.bin: vmlinux FORCE
+	$(call if_changed,objcopy)
+
+$(obj)/vmlinux.gz: $(obj)/vmlinux.bin FORCE
+	$(call if_changed,gzip)
+
+$(obj)/vmImage: $(obj)/vmlinux.gz FORCE
+	$(call if_changed,uimage)
+	@$(kecho) 'Kernel: $@ is ready'
+
+$(obj)/zImage: $(obj)/compressed/vmlinux FORCE
+	$(call if_changed,objcopy)
+	@$(kecho) 'Kernel: $@ is ready'
+
+$(obj)/compressed/vmlinux: $(obj)/vmlinux.gz FORCE
+	$(Q)$(MAKE) $(build)=$(obj)/compressed $@
diff --git a/arch/nios2/boot/compressed/Makefile b/arch/nios2/boot/compressed/Makefile
new file mode 100644
index 000000000..791e43092
--- /dev/null
+++ b/arch/nios2/boot/compressed/Makefile
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# create a compressed vmlinux image from the original vmlinux
+#
+
+targets		:= vmlinux head.o misc.o piggy.o vmlinux.lds
+asflags-y	:=
+
+OBJECTS = $(obj)/head.o $(obj)/misc.o
+
+LDFLAGS_vmlinux := -T
+
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS) $(obj)/piggy.o FORCE
+	$(call if_changed,ld)
+
+LDFLAGS_piggy.o := -r --format binary --oformat elf32-littlenios2 -T
+
+$(obj)/piggy.o: $(obj)/vmlinux.scr $(obj)/../vmlinux.gz FORCE
+	$(call if_changed,ld)
diff --git a/arch/nios2/boot/compressed/console.c b/arch/nios2/boot/compressed/console.c
new file mode 100644
index 000000000..2cb2e7c9f
--- /dev/null
+++ b/arch/nios2/boot/compressed/console.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (C) 2008-2010 Thomas Chou <thomas@wytron.com.tw>
+ */
+
+#include <linux/io.h>
+
+#if (defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE) && defined(JTAG_UART_BASE))\
+	|| (defined(CONFIG_SERIAL_ALTERA_UART_CONSOLE) && defined(UART0_BASE))
+static void *my_ioremap(unsigned long physaddr)
+{
+	return (void *)(physaddr | CONFIG_NIOS2_IO_REGION_BASE);
+}
+#endif
+
+#if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE) && defined(JTAG_UART_BASE)
+
+#define ALTERA_JTAGUART_SIZE				8
+#define ALTERA_JTAGUART_DATA_REG			0
+#define ALTERA_JTAGUART_CONTROL_REG			4
+#define ALTERA_JTAGUART_CONTROL_AC_MSK			(0x00000400)
+#define ALTERA_JTAGUART_CONTROL_WSPACE_MSK		(0xFFFF0000)
+static void *uartbase;
+
+#if defined(CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE_BYPASS)
+static void jtag_putc(int ch)
+{
+	if (readl(uartbase + ALTERA_JTAGUART_CONTROL_REG) &
+		ALTERA_JTAGUART_CONTROL_WSPACE_MSK)
+		writeb(ch, uartbase + ALTERA_JTAGUART_DATA_REG);
+}
+#else
+static void jtag_putc(int ch)
+{
+	while ((readl(uartbase + ALTERA_JTAGUART_CONTROL_REG) &
+		ALTERA_JTAGUART_CONTROL_WSPACE_MSK) == 0)
+		;
+	writeb(ch, uartbase + ALTERA_JTAGUART_DATA_REG);
+}
+#endif
+
+static int putchar(int ch)
+{
+	jtag_putc(ch);
+	return ch;
+}
+
+static void console_init(void)
+{
+	uartbase = my_ioremap((unsigned long) JTAG_UART_BASE);
+	writel(ALTERA_JTAGUART_CONTROL_AC_MSK,
+		uartbase + ALTERA_JTAGUART_CONTROL_REG);
+}
+
+#elif defined(CONFIG_SERIAL_ALTERA_UART_CONSOLE) && defined(UART0_BASE)
+
+#define ALTERA_UART_SIZE		32
+#define ALTERA_UART_TXDATA_REG		4
+#define ALTERA_UART_STATUS_REG		8
+#define ALTERA_UART_DIVISOR_REG		16
+#define ALTERA_UART_STATUS_TRDY_MSK	(0x40)
+static unsigned uartbase;
+
+static void uart_putc(int ch)
+{
+	int i;
+
+	for (i = 0; (i < 0x10000); i++) {
+		if (readw(uartbase + ALTERA_UART_STATUS_REG) &
+			ALTERA_UART_STATUS_TRDY_MSK)
+			break;
+	}
+	writeb(ch, uartbase + ALTERA_UART_TXDATA_REG);
+}
+
+static int putchar(int ch)
+{
+	uart_putc(ch);
+	if (ch == '\n')
+		uart_putc('\r');
+	return ch;
+}
+
+static void console_init(void)
+{
+	unsigned int baud, baudclk;
+
+	uartbase = (unsigned long) my_ioremap((unsigned long) UART0_BASE);
+	baud = CONFIG_SERIAL_ALTERA_UART_BAUDRATE;
+	baudclk = UART0_FREQ / baud;
+	writew(baudclk, uartbase + ALTERA_UART_DIVISOR_REG);
+}
+
+#else
+
+static int putchar(int ch)
+{
+	return ch;
+}
+
+static void console_init(void)
+{
+}
+
+#endif
+
+static int puts(const char *s)
+{
+	while (*s)
+		putchar(*s++);
+	return 0;
+}
diff --git a/arch/nios2/boot/compressed/head.S b/arch/nios2/boot/compressed/head.S
new file mode 100644
index 000000000..15c6c48dd
--- /dev/null
+++ b/arch/nios2/boot/compressed/head.S
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * Based on arch/nios2/kernel/head.S
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ */
+
+/*
+ *  This code can be loaded anywhere, eg FLASH ROM as reset vector,
+ *  as long as output does not overlap it.
+ */
+
+#include <linux/linkage.h>
+#include <asm/cache.h>
+
+	.text
+	.set noat
+ENTRY(_start)
+	wrctl	status, r0		/* disable interrupt */
+	/* invalidate all instruction cache */
+	movia	r1, NIOS2_ICACHE_SIZE
+	movui	r2, NIOS2_ICACHE_LINE_SIZE
+1:	initi	r1
+	sub	r1, r1, r2
+	bgt	r1, r0, 1b
+	/* invalidate all data cache */
+	movia	r1, NIOS2_DCACHE_SIZE
+	movui	r2, NIOS2_DCACHE_LINE_SIZE
+1:	initd	0(r1)
+	sub	r1, r1, r2
+	bgt	r1, r0, 1b
+
+	nextpc	r1			/* Find out where we are */
+chkadr:
+	movia	r2, chkadr
+	beq	r1, r2, finish_move	/* We are running in correct address,
+					   done */
+	/* move code, r1: src, r2: dest, r3: last dest */
+	addi	r1, r1, (_start - chkadr)	/* Source */
+	movia	r2, _start		/* Destination */
+	movia	r3, __bss_start		/* End of copy */
+1:	ldw	r8, 0(r1)		/* load a word from [r1] */
+	stw	r8, 0(r2)		/* stort a word to dest [r2] */
+	addi	r1, r1, 4		/* inc the src addr */
+	addi	r2, r2, 4		/* inc the dest addr */
+	blt	r2, r3, 1b
+	/* flush the data cache after moving */
+	movia	r1, NIOS2_DCACHE_SIZE
+	movui	r2, NIOS2_DCACHE_LINE_SIZE
+1:	flushd	0(r1)
+	sub	r1, r1, r2
+	bgt	r1, r0, 1b
+	movia	r1, finish_move
+	jmp	r1			/* jmp to linked address */
+
+finish_move:
+	/* zero out the .bss segment (uninitialized common data) */
+	movia	r2, __bss_start		/* presume nothing is between */
+	movia	r1, _end		/* the .bss and _end. */
+1: 	stb	r0, 0(r2)
+	addi	r2, r2, 1
+	bne	r1, r2, 1b
+	/*
+	 * set up the stack pointer, some where higher than _end.
+	 * The stack space must be greater than 32K for decompress.
+	 */
+	movia	sp, 0x10000
+	add	sp, sp, r1
+	/* save args passed from u-boot, maybe */
+	addi	sp, sp, -16
+	stw	r4, 0(sp)
+	stw	r5, 4(sp)
+	stw	r6, 8(sp)
+	stw	r7, 12(sp)
+	/* decompress the kernel */
+	call	decompress_kernel
+	/* pass saved args to kernel */
+	ldw	r4, 0(sp)
+	ldw	r5, 4(sp)
+	ldw	r6, 8(sp)
+	ldw	r7, 12(sp)
+
+	/* flush all data cache after decompressing */
+	movia	r1, NIOS2_DCACHE_SIZE
+	movui	r2, NIOS2_DCACHE_LINE_SIZE
+1:	flushd	0(r1)
+	sub	r1, r1, r2
+	bgt	r1, r0, 1b
+	/* flush all instruction cache */
+	movia	r1, NIOS2_ICACHE_SIZE
+	movui	r2, NIOS2_ICACHE_LINE_SIZE
+1:	flushi	r1
+	sub	r1, r1, r2
+	bgt	r1, r0, 1b
+	flushp
+	/* jump to start real kernel */
+	movia	r1, (CONFIG_NIOS2_MEM_BASE | CONFIG_NIOS2_KERNEL_REGION_BASE)
+	jmp	r1
+
+	.balign 512
+fake_headers_as_bzImage:
+	.short	0
+	.ascii	"HdrS"
+	.short	0x0202
+	.short	0
+	.short	0
+	.byte	0x00, 0x10
+	.short	0
+	.byte	0
+	.byte	1
+	.byte	0x00, 0x80
+	.long	0
+	.long	0
diff --git a/arch/nios2/boot/compressed/misc.c b/arch/nios2/boot/compressed/misc.c
new file mode 100644
index 000000000..42fc4bbe1
--- /dev/null
+++ b/arch/nios2/boot/compressed/misc.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * This is a collection of several routines from gzip-1.0.3
+ * adapted for Linux.
+ *
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ *
+ * Adapted for SH by Stuart Menefy, Aug 1999
+ *
+ * Modified to use standard LinuxSH BIOS by Greg Banks 7Jul2000
+ *
+ * Based on arch/sh/boot/compressed/misc.c
+ */
+
+#include <linux/string.h>
+
+/*
+ * gzip declarations
+ */
+#define OF(args)  args
+#define STATIC static
+
+#undef memset
+#undef memcpy
+#define memzero(s, n)		memset((s), 0, (n))
+
+typedef unsigned char  uch;
+typedef unsigned short ush;
+typedef unsigned long  ulg;
+#define WSIZE 0x8000		/* Window size must be at least 32k, */
+				/* and a power of two */
+
+static uch *inbuf;		/* input buffer */
+static uch window[WSIZE];	/* Sliding window buffer */
+
+static unsigned insize;	/* valid bytes in inbuf */
+static unsigned inptr;	/* index of next byte to be processed in inbuf */
+static unsigned outcnt;	/* bytes in output buffer */
+
+/* gzip flag byte */
+#define ASCII_FLAG	0x01 /* bit 0 set: file probably ASCII text */
+#define CONTINUATION	0x02 /* bit 1 set: continuation of multi-part gzip
+				file */
+#define EXTRA_FIELD	0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME	0x08 /* bit 3 set: original file name present */
+#define COMMENT		0x10 /* bit 4 set: file comment present */
+#define ENCRYPTED	0x20 /* bit 5 set: file is encrypted */
+#define RESERVED	0xC0 /* bit 6,7:   reserved */
+
+#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
+
+#ifdef DEBUG
+#  define Assert(cond, msg) {if (!(cond)) error(msg); }
+#  define Trace(x) fprintf x
+#  define Tracev(x) {if (verbose) fprintf x ; }
+#  define Tracevv(x) {if (verbose > 1) fprintf x ; }
+#  define Tracec(c, x) {if (verbose && (c)) fprintf x ; }
+#  define Tracecv(c, x) {if (verbose > 1 && (c)) fprintf x ; }
+#else
+#  define Assert(cond, msg)
+#  define Trace(x)
+#  define Tracev(x)
+#  define Tracevv(x)
+#  define Tracec(c, x)
+#  define Tracecv(c, x)
+#endif
+static int  fill_inbuf(void);
+static void flush_window(void);
+static void error(char *m);
+
+extern char input_data[];
+extern int input_len;
+
+static long bytes_out;
+static uch *output_data;
+static unsigned long output_ptr;
+
+#include "console.c"
+
+static void error(char *m);
+
+int puts(const char *);
+
+extern int _end;
+static unsigned long free_mem_ptr;
+static unsigned long free_mem_end_ptr;
+
+#define HEAP_SIZE			0x10000
+
+#include "../../../../lib/inflate.c"
+
+void *memset(void *s, int c, size_t n)
+{
+	int i;
+	char *ss = (char *)s;
+
+	for (i = 0; i < n; i++)
+		ss[i] = c;
+	return s;
+}
+
+void *memcpy(void *__dest, __const void *__src, size_t __n)
+{
+	int i;
+	char *d = (char *)__dest, *s = (char *)__src;
+
+	for (i = 0; i < __n; i++)
+		d[i] = s[i];
+	return __dest;
+}
+
+/*
+ * Fill the input buffer. This is called only when the buffer is empty
+ * and at least one byte is really needed.
+ */
+static int fill_inbuf(void)
+{
+	if (insize != 0)
+		error("ran out of input data");
+
+	inbuf = input_data;
+	insize = input_len;
+	inptr = 1;
+	return inbuf[0];
+}
+
+/*
+ * Write the output window window[0..outcnt-1] and update crc and bytes_out.
+ * (Used for the decompressed data only.)
+ */
+static void flush_window(void)
+{
+	ulg c = crc;	/* temporary variable */
+	unsigned n;
+	uch *in, *out, ch;
+
+	in = window;
+	out = &output_data[output_ptr];
+	for (n = 0; n < outcnt; n++) {
+		ch = *out++ = *in++;
+		c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
+	}
+	crc = c;
+	bytes_out += (ulg)outcnt;
+	output_ptr += (ulg)outcnt;
+	outcnt = 0;
+}
+
+static void error(char *x)
+{
+	puts("\nERROR\n");
+	puts(x);
+	puts("\n\n -- System halted");
+
+	while (1)	/* Halt */
+		;
+}
+
+void decompress_kernel(void)
+{
+	output_data = (void *) (CONFIG_NIOS2_MEM_BASE |
+				CONFIG_NIOS2_KERNEL_REGION_BASE);
+	output_ptr = 0;
+	free_mem_ptr = (unsigned long)&_end;
+	free_mem_end_ptr = free_mem_ptr + HEAP_SIZE;
+
+	console_init();
+	makecrc();
+	puts("Uncompressing Linux... ");
+	gunzip();
+	puts("Ok, booting the kernel.\n");
+}
diff --git a/arch/nios2/boot/compressed/vmlinux.lds.S b/arch/nios2/boot/compressed/vmlinux.lds.S
new file mode 100644
index 000000000..9b02d0c97
--- /dev/null
+++ b/arch/nios2/boot/compressed/vmlinux.lds.S
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ */
+
+#include <asm-generic/vmlinux.lds.h>
+
+OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2")
+
+OUTPUT_ARCH(nios)
+ENTRY(_start)	/* Defined in head.S */
+
+SECTIONS
+{
+	. = (CONFIG_NIOS2_MEM_BASE + CONFIG_NIOS2_BOOT_LINK_OFFSET) |	\
+		CONFIG_NIOS2_KERNEL_REGION_BASE;
+
+	_text = .;
+	.text : { *(.text) } = 0
+	.rodata : { *(.rodata) *(.rodata.*) }
+	_etext = .;
+
+	. = ALIGN(32 / 8);
+	.data : { *(.data) }
+	. = ALIGN(32 / 8);
+	_got = .;
+	.got : {
+		*(.got.plt)
+		*(.igot.plt)
+		*(.got)
+		*(.igot)
+	}
+	_egot = .;
+	_edata =  .;
+
+	. = ALIGN(32 / 8);
+	__bss_start = .;
+	.bss : { *(.bss) *(.sbss) }
+	. = ALIGN(32 / 8);
+	_ebss = .;
+	end = . ;
+	_end = . ;
+
+	got_len = (_egot - _got);
+}
diff --git a/arch/nios2/boot/compressed/vmlinux.scr b/arch/nios2/boot/compressed/vmlinux.scr
new file mode 100644
index 000000000..28c42f1d1
--- /dev/null
+++ b/arch/nios2/boot/compressed/vmlinux.scr
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+SECTIONS
+{
+	.data : {
+		input_len = .;
+		LONG(input_data_end - input_data) input_data = .;
+		*(.data)
+		. = ALIGN(4);
+		input_data_end = .;
+	}
+}
diff --git a/arch/nios2/boot/dts/10m50_devboard.dts b/arch/nios2/boot/dts/10m50_devboard.dts
new file mode 100644
index 000000000..0e7e5b0dd
--- /dev/null
+++ b/arch/nios2/boot/dts/10m50_devboard.dts
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 Altera Corporation. All rights reserved.
+ */
+
+/dts-v1/;
+
+/ {
+	model = "Altera NiosII Max10";
+	compatible = "altr,niosii-max10";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu: cpu@0 {
+			device_type = "cpu";
+			compatible = "altr,nios2-1.1";
+			reg = <0x00000000>;
+			interrupt-controller;
+			#interrupt-cells = <1>;
+			altr,exception-addr = <0xc8000120>;
+			altr,fast-tlb-miss-addr = <0xc0000100>;
+			altr,has-div = <1>;
+			altr,has-initda = <1>;
+			altr,has-mmu = <1>;
+			altr,has-mul = <1>;
+			altr,implementation = "fast";
+			altr,pid-num-bits = <8>;
+			altr,reset-addr = <0xd4000000>;
+			altr,tlb-num-entries = <256>;
+			altr,tlb-num-ways = <16>;
+			altr,tlb-ptr-sz = <8>;
+			clock-frequency = <75000000>;
+			dcache-line-size = <32>;
+			dcache-size = <32768>;
+			icache-line-size = <32>;
+			icache-size = <32768>;
+		};
+	};
+
+	memory {
+		device_type = "memory";
+		reg = <0x08000000 0x08000000>,
+			<0x00000000 0x00000400>;
+	};
+
+	sopc0: sopc@0 {
+		device_type = "soc";
+		ranges;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "altr,avalon", "simple-bus";
+		bus-frequency = <75000000>;
+
+		jtag_uart: serial@18001530 {
+			compatible = "altr,juart-1.0";
+			reg = <0x18001530 0x00000008>;
+			interrupt-parent = <&cpu>;
+			interrupts = <7>;
+		};
+
+		a_16550_uart_0: serial@18001600 {
+			compatible = "altr,16550-FIFO32", "ns16550a";
+			reg = <0x18001600 0x00000200>;
+			interrupt-parent = <&cpu>;
+			interrupts = <1>;
+			auto-flow-control = <1>;
+			clock-frequency = <50000000>;
+			fifo-size = <32>;
+			reg-io-width = <4>;
+			reg-shift = <2>;
+			tx-threshold = <16>;
+		};
+
+		sysid: sysid@18001528 {
+			compatible = "altr,sysid-1.0";
+			reg = <0x18001528 0x00000008>;
+			id = <4207856382>;
+			timestamp = <1431309290>;
+		};
+
+		rgmii_0_eth_tse_0: ethernet@400 {
+			compatible = "altr,tse-msgdma-1.0", "altr,tse-1.0";
+			reg = <0x00000400 0x00000400>,
+				<0x00000820 0x00000020>,
+				<0x00000800 0x00000020>,
+				<0x000008c0 0x00000008>,
+				<0x00000840 0x00000020>,
+				<0x00000860 0x00000020>;
+			reg-names = "control_port", "rx_csr", "rx_desc", "rx_resp", "tx_csr", "tx_desc";
+			interrupt-parent = <&cpu>;
+			interrupts = <2 3>;
+			interrupt-names = "rx_irq", "tx_irq";
+			rx-fifo-depth = <8192>;
+			tx-fifo-depth = <8192>;
+			address-bits = <48>;
+			max-frame-size = <1500>;
+			local-mac-address = [00 00 00 00 00 00];
+			altr,has-supplementary-unicast;
+			altr,enable-sup-addr = <1>;
+			altr,has-hash-multicast-filter;
+			altr,enable-hash = <1>;
+			phy-mode = "rgmii-id";
+			phy-handle = <&phy0>;
+			rgmii_0_eth_tse_0_mdio: mdio {
+				compatible = "altr,tse-mdio";
+				#address-cells = <1>;
+				#size-cells = <0>;
+				phy0: ethernet-phy@0 {
+					reg = <0>;
+					device_type = "ethernet-phy";
+				};
+			};
+		};
+
+		enet_pll: clock@0 {
+			compatible = "altr,pll-1.0";
+			#clock-cells = <1>;
+
+			enet_pll_c0: enet_pll_c0 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <125000000>;
+				clock-output-names = "enet_pll-c0";
+			};
+
+			enet_pll_c1: enet_pll_c1 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <25000000>;
+				clock-output-names = "enet_pll-c1";
+			};
+
+			enet_pll_c2: enet_pll_c2 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <2500000>;
+				clock-output-names = "enet_pll-c2";
+			};
+		};
+
+		sys_pll: clock@1 {
+			compatible = "altr,pll-1.0";
+			#clock-cells = <1>;
+
+			sys_pll_c0: sys_pll_c0 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <100000000>;
+				clock-output-names = "sys_pll-c0";
+			};
+
+			sys_pll_c1: sys_pll_c1 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <50000000>;
+				clock-output-names = "sys_pll-c1";
+			};
+
+			sys_pll_c2: sys_pll_c2 {
+				compatible = "fixed-clock";
+				#clock-cells = <0>;
+				clock-frequency = <75000000>;
+				clock-output-names = "sys_pll-c2";
+			};
+		};
+
+		sys_clk_timer: timer@18001440 {
+			compatible = "altr,timer-1.0";
+			reg = <0x18001440 0x00000020>;
+			interrupt-parent = <&cpu>;
+			interrupts = <0>;
+			clock-frequency = <75000000>;
+		};
+
+		led_pio: gpio@180014d0 {
+			compatible = "altr,pio-1.0";
+			reg = <0x180014d0 0x00000010>;
+			altr,ngpio = <4>;
+			#gpio-cells = <2>;
+			gpio-controller;
+		};
+
+		button_pio: gpio@180014c0 {
+			compatible = "altr,pio-1.0";
+			reg = <0x180014c0 0x00000010>;
+			interrupt-parent = <&cpu>;
+			interrupts = <6>;
+			altr,ngpio = <3>;
+			altr,interrupt-type = <2>;
+			edge_type = <1>;
+			level_trigger = <0>;
+			#gpio-cells = <2>;
+			gpio-controller;
+		};
+
+		sys_clk_timer_1: timer@880 {
+			compatible = "altr,timer-1.0";
+			reg = <0x00000880 0x00000020>;
+			interrupt-parent = <&cpu>;
+			interrupts = <5>;
+			clock-frequency = <75000000>;
+		};
+
+		fpga_leds: leds {
+			compatible = "gpio-leds";
+
+			led_fpga0: fpga0 {
+				label = "fpga_led0";
+				gpios = <&led_pio 0 1>;
+			};
+
+			led_fpga1: fpga1 {
+				label = "fpga_led1";
+				gpios = <&led_pio 1 1>;
+			};
+
+			led_fpga2: fpga2 {
+				label = "fpga_led2";
+				gpios = <&led_pio 2 1>;
+			};
+
+			led_fpga3: fpga3 {
+				label = "fpga_led3";
+				gpios = <&led_pio 3 1>;
+			};
+		};
+	};
+
+	chosen {
+		bootargs = "debug earlycon console=ttyS0,115200";
+		stdout-path = &a_16550_uart_0;
+	};
+};
diff --git a/arch/nios2/boot/dts/3c120_devboard.dts b/arch/nios2/boot/dts/3c120_devboard.dts
new file mode 100644
index 000000000..3ee316906
--- /dev/null
+++ b/arch/nios2/boot/dts/3c120_devboard.dts
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  Copyright (C) 2013 Altera Corporation
+ *
+ * This file is generated by sopc2dts.
+ */
+
+/dts-v1/;
+
+/ {
+	model = "altr,qsys_ghrd_3c120";
+	compatible = "altr,qsys_ghrd_3c120";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu: cpu@0 {
+			device_type = "cpu";
+			compatible = "altr,nios2-1.0";
+			reg = <0x00000000>;
+			interrupt-controller;
+			#interrupt-cells = <1>;
+			clock-frequency = <125000000>;
+			dcache-line-size = <32>;
+			icache-line-size = <32>;
+			dcache-size = <32768>;
+			icache-size = <32768>;
+			altr,implementation = "fast";
+			altr,pid-num-bits = <8>;
+			altr,tlb-num-ways = <16>;
+			altr,tlb-num-entries = <128>;
+			altr,tlb-ptr-sz = <7>;
+			altr,has-div = <1>;
+			altr,has-mul = <1>;
+			altr,reset-addr = <0xc2800000>;
+			altr,fast-tlb-miss-addr = <0xc7fff400>;
+			altr,exception-addr = <0xd0000020>;
+			altr,has-initda = <1>;
+			altr,has-mmu = <1>;
+		};
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x10000000 0x08000000>,
+			<0x07fff400 0x00000400>;
+	};
+
+	sopc@0 {
+		device_type = "soc";
+		ranges;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "altr,avalon", "simple-bus";
+		bus-frequency = <125000000>;
+
+		pb_cpu_to_io: bridge@8000000 {
+			compatible = "simple-bus";
+			reg = <0x08000000 0x00800000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges = <0x00002000 0x08002000 0x00002000>,
+				<0x00004000 0x08004000 0x00000400>,
+				<0x00004400 0x08004400 0x00000040>,
+				<0x00004800 0x08004800 0x00000040>,
+				<0x00004c80 0x08004c80 0x00000020>,
+				<0x00004d50 0x08004d50 0x00000008>,
+				<0x00008000 0x08008000 0x00000020>,
+				<0x00400000 0x08400000 0x00000020>;
+
+			timer_1ms: timer@400000 {
+				compatible = "altr,timer-1.0";
+				reg = <0x00400000 0x00000020>;
+				interrupt-parent = <&cpu>;
+				interrupts = <11>;
+				clock-frequency = <125000000>;
+			};
+
+			timer_0: timer@8000 {
+				compatible = "altr,timer-1.0";
+				reg = < 0x00008000 0x00000020 >;
+				interrupt-parent = < &cpu >;
+				interrupts = < 5 >;
+				clock-frequency = < 125000000 >;
+			};
+
+			jtag_uart: serial@4d50 {
+				compatible = "altr,juart-1.0";
+				reg = <0x00004d50 0x00000008>;
+				interrupt-parent = <&cpu>;
+				interrupts = <1>;
+			};
+
+			tse_mac: ethernet@4000 {
+				compatible = "altr,tse-1.0";
+				reg = <0x00004000 0x00000400>,
+					<0x00004400 0x00000040>,
+					<0x00004800 0x00000040>,
+					<0x00002000 0x00002000>;
+				reg-names = "control_port", "rx_csr", "tx_csr", "s1";
+				interrupt-parent = <&cpu>;
+				interrupts = <2 3>;
+				interrupt-names = "rx_irq", "tx_irq";
+				rx-fifo-depth = <8192>;
+				tx-fifo-depth = <8192>;
+				max-frame-size = <1500>;
+				local-mac-address = [ 00 00 00 00 00 00 ];
+				phy-mode = "rgmii-id";
+				phy-handle = <&phy0>;
+				tse_mac_mdio: mdio {
+					compatible = "altr,tse-mdio";
+					#address-cells = <1>;
+					#size-cells = <0>;
+					phy0: ethernet-phy@18 {
+						reg = <18>;
+						device_type = "ethernet-phy";
+					};
+				};
+			};
+
+			uart: serial@4c80 {
+				compatible = "altr,uart-1.0";
+				reg = <0x00004c80 0x00000020>;
+				interrupt-parent = <&cpu>;
+				interrupts = <10>;
+				current-speed = <115200>;
+				clock-frequency = <62500000>;
+			};
+		};
+
+		cfi_flash_64m: flash@0 {
+			compatible = "cfi-flash";
+			reg = <0x00000000 0x04000000>;
+			bank-width = <2>;
+			device-width = <1>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			partition@800000 {
+				reg = <0x00800000 0x01e00000>;
+				label = "JFFS2 Filesystem";
+			};
+		};
+	};
+
+	chosen {
+		bootargs = "debug earlycon console=ttyJ0,115200";
+		stdout-path = &jtag_uart;
+	};
+};
diff --git a/arch/nios2/boot/dts/Makefile b/arch/nios2/boot/dts/Makefile
new file mode 100644
index 000000000..e9e31bb40
--- /dev/null
+++ b/arch/nios2/boot/dts/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-y := $(patsubst %.dts,%.dtb.o,$(CONFIG_NIOS2_DTB_SOURCE))
+
+dtstree		:= $(srctree)/$(src)
+dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
diff --git a/arch/nios2/boot/install.sh b/arch/nios2/boot/install.sh
new file mode 100755
index 000000000..34a2feec4
--- /dev/null
+++ b/arch/nios2/boot/install.sh
@@ -0,0 +1,30 @@
+#!/bin/sh
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+# Copyright (C) 1995 by Linus Torvalds
+#
+# Adapted from code in arch/i386/boot/Makefile by H. Peter Anvin
+#
+# "make install" script for nios2 architecture
+#
+# Arguments:
+#   $1 - kernel version
+#   $2 - kernel image file
+#   $3 - kernel map file
+#   $4 - default install path (blank if root directory)
+
+if [ -f $4/vmlinuz ]; then
+	mv $4/vmlinuz $4/vmlinuz.old
+fi
+
+if [ -f $4/System.map ]; then
+	mv $4/System.map $4/System.old
+fi
+
+cat $2 > $4/vmlinuz
+cp $3 $4/System.map
+
+sync
diff --git a/arch/nios2/configs/10m50_defconfig b/arch/nios2/configs/10m50_defconfig
new file mode 100644
index 000000000..91c3fce4d
--- /dev/null
+++ b/arch/nios2/configs/10m50_defconfig
@@ -0,0 +1,77 @@
+CONFIG_SYSVIPC=y
+CONFIG_NO_HZ_IDLE=y
+CONFIG_BSD_PROCESS_ACCT=y
+CONFIG_LOG_BUF_SHIFT=14
+# CONFIG_ELF_CORE is not set
+# CONFIG_EPOLL is not set
+# CONFIG_SIGNALFD is not set
+# CONFIG_TIMERFD is not set
+# CONFIG_EVENTFD is not set
+# CONFIG_SHMEM is not set
+# CONFIG_AIO is not set
+CONFIG_EMBEDDED=y
+CONFIG_SLAB=y
+CONFIG_MODULES=y
+CONFIG_MODULE_UNLOAD=y
+CONFIG_NIOS2_MEM_BASE=0x8000000
+CONFIG_NIOS2_HW_MUL_SUPPORT=y
+CONFIG_NIOS2_HW_DIV_SUPPORT=y
+CONFIG_CUSTOM_CACHE_SETTINGS=y
+CONFIG_NIOS2_DCACHE_SIZE=0x8000
+CONFIG_NIOS2_ICACHE_SIZE=0x8000
+# CONFIG_NIOS2_CMDLINE_IGNORE_DTB is not set
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_INET=y
+CONFIG_IP_MULTICAST=y
+CONFIG_IP_PNP=y
+CONFIG_IP_PNP_DHCP=y
+CONFIG_IP_PNP_BOOTP=y
+CONFIG_IP_PNP_RARP=y
+# CONFIG_INET_XFRM_MODE_TRANSPORT is not set
+# CONFIG_INET_XFRM_MODE_TUNNEL is not set
+# CONFIG_INET_XFRM_MODE_BEET is not set
+# CONFIG_IPV6 is not set
+# CONFIG_WIRELESS is not set
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+# CONFIG_FW_LOADER is not set
+CONFIG_MTD=y
+CONFIG_MTD_CMDLINE_PARTS=y
+CONFIG_MTD_BLOCK=y
+CONFIG_MTD_CFI=y
+CONFIG_MTD_CFI_INTELEXT=y
+CONFIG_MTD_CFI_AMDSTD=y
+CONFIG_BLK_DEV_LOOP=y
+CONFIG_NETDEVICES=y
+CONFIG_ALTERA_TSE=y
+CONFIG_MARVELL_PHY=y
+# CONFIG_WLAN is not set
+# CONFIG_INPUT_MOUSE is not set
+# CONFIG_SERIO_SERPORT is not set
+# CONFIG_VT is not set
+CONFIG_SERIAL_8250=y
+# CONFIG_SERIAL_8250_DEPRECATED_OPTIONS is not set
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SERIAL_OF_PLATFORM=y
+CONFIG_SERIAL_ALTERA_JTAGUART=y
+# CONFIG_HW_RANDOM is not set
+CONFIG_GPIOLIB=y
+CONFIG_GPIO_SYSFS=y
+CONFIG_GPIO_ALTERA=y
+# CONFIG_HWMON is not set
+# CONFIG_USB_SUPPORT is not set
+CONFIG_NEW_LEDS=y
+CONFIG_LEDS_CLASS=y
+CONFIG_LEDS_GPIO=y
+CONFIG_LEDS_TRIGGERS=y
+CONFIG_LEDS_TRIGGER_HEARTBEAT=y
+# CONFIG_DNOTIFY is not set
+# CONFIG_INOTIFY_USER is not set
+CONFIG_JFFS2_FS=y
+CONFIG_NFS_FS=y
+CONFIG_NFS_V3_ACL=y
+CONFIG_ROOT_NFS=y
+CONFIG_SUNRPC_DEBUG=y
+CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
diff --git a/arch/nios2/configs/3c120_defconfig b/arch/nios2/configs/3c120_defconfig
new file mode 100644
index 000000000..c42ad7e16
--- /dev/null
+++ b/arch/nios2/configs/3c120_defconfig
@@ -0,0 +1,74 @@
+CONFIG_SYSVIPC=y
+CONFIG_NO_HZ_IDLE=y
+CONFIG_BSD_PROCESS_ACCT=y
+CONFIG_LOG_BUF_SHIFT=14
+# CONFIG_ELF_CORE is not set
+# CONFIG_EPOLL is not set
+# CONFIG_SIGNALFD is not set
+# CONFIG_TIMERFD is not set
+# CONFIG_EVENTFD is not set
+# CONFIG_SHMEM is not set
+# CONFIG_AIO is not set
+CONFIG_EMBEDDED=y
+CONFIG_SLAB=y
+CONFIG_MODULES=y
+CONFIG_MODULE_UNLOAD=y
+CONFIG_NIOS2_MEM_BASE=0x10000000
+CONFIG_NIOS2_HW_MUL_SUPPORT=y
+CONFIG_NIOS2_HW_DIV_SUPPORT=y
+CONFIG_CUSTOM_CACHE_SETTINGS=y
+CONFIG_NIOS2_DCACHE_SIZE=0x8000
+CONFIG_NIOS2_ICACHE_SIZE=0x8000
+# CONFIG_NIOS2_CMDLINE_IGNORE_DTB is not set
+CONFIG_NIOS2_PASS_CMDLINE=y
+CONFIG_NIOS2_BOOT_LINK_OFFSET=0x00800000
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_INET=y
+CONFIG_IP_MULTICAST=y
+CONFIG_IP_PNP=y
+CONFIG_IP_PNP_DHCP=y
+CONFIG_IP_PNP_BOOTP=y
+CONFIG_IP_PNP_RARP=y
+# CONFIG_INET_XFRM_MODE_TRANSPORT is not set
+# CONFIG_INET_XFRM_MODE_TUNNEL is not set
+# CONFIG_INET_XFRM_MODE_BEET is not set
+# CONFIG_IPV6 is not set
+# CONFIG_WIRELESS is not set
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+# CONFIG_FW_LOADER is not set
+CONFIG_MTD=y
+CONFIG_MTD_CMDLINE_PARTS=y
+CONFIG_MTD_BLOCK=y
+CONFIG_MTD_CFI=y
+CONFIG_MTD_CFI_INTELEXT=y
+CONFIG_MTD_CFI_AMDSTD=y
+CONFIG_MTD_PHYSMAP_OF=y
+CONFIG_BLK_DEV_LOOP=y
+CONFIG_NETDEVICES=y
+CONFIG_ALTERA_TSE=y
+CONFIG_MARVELL_PHY=y
+# CONFIG_WLAN is not set
+# CONFIG_INPUT_MOUSE is not set
+# CONFIG_SERIO_SERPORT is not set
+# CONFIG_VT is not set
+CONFIG_SERIAL_ALTERA_JTAGUART=y
+CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE=y
+CONFIG_SERIAL_ALTERA_UART=y
+# CONFIG_HW_RANDOM is not set
+# CONFIG_HWMON is not set
+# CONFIG_USB_SUPPORT is not set
+CONFIG_NEW_LEDS=y
+CONFIG_LEDS_CLASS=y
+CONFIG_LEDS_TRIGGERS=y
+CONFIG_LEDS_TRIGGER_HEARTBEAT=y
+# CONFIG_DNOTIFY is not set
+# CONFIG_INOTIFY_USER is not set
+CONFIG_JFFS2_FS=y
+CONFIG_NFS_FS=y
+CONFIG_NFS_V3_ACL=y
+CONFIG_ROOT_NFS=y
+CONFIG_SUNRPC_DEBUG=y
+CONFIG_DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT=y
diff --git a/arch/nios2/include/asm/Kbuild b/arch/nios2/include/asm/Kbuild
new file mode 100644
index 000000000..7fe743755
--- /dev/null
+++ b/arch/nios2/include/asm/Kbuild
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+generic-y += cmpxchg.h
+generic-y += extable.h
+generic-y += kvm_para.h
+generic-y += mcs_spinlock.h
+generic-y += spinlock.h
+generic-y += user.h
diff --git a/arch/nios2/include/asm/asm-macros.h b/arch/nios2/include/asm/asm-macros.h
new file mode 100644
index 000000000..522e50a17
--- /dev/null
+++ b/arch/nios2/include/asm/asm-macros.h
@@ -0,0 +1,298 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Macro used to simplify coding multi-line assembler.
+ * Some of the bit test macro can simplify down to one line
+ * depending on the mask value.
+ *
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * All rights reserved.
+ */
+#ifndef _ASM_NIOS2_ASMMACROS_H
+#define _ASM_NIOS2_ASMMACROS_H
+/*
+ * ANDs reg2 with mask and places the result in reg1.
+ *
+ * You cannnot use the same register for reg1 & reg2.
+ */
+
+.macro ANDI32	reg1, reg2, mask
+.if \mask & 0xffff
+	.if \mask & 0xffff0000
+		movhi	\reg1, %hi(\mask)
+		movui	\reg1, %lo(\mask)
+		and	\reg1, \reg1, \reg2
+	.else
+		andi	\reg1, \reg2, %lo(\mask)
+	.endif
+.else
+	andhi	\reg1, \reg2, %hi(\mask)
+.endif
+.endm
+
+/*
+ * ORs reg2 with mask and places the result in reg1.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro ORI32	reg1, reg2, mask
+.if \mask & 0xffff
+	.if \mask & 0xffff0000
+		orhi	\reg1, \reg2, %hi(\mask)
+		ori	\reg1, \reg2, %lo(\mask)
+	.else
+		ori	\reg1, \reg2, %lo(\mask)
+	.endif
+.else
+	orhi	\reg1, \reg2, %hi(\mask)
+.endif
+.endm
+
+/*
+ * XORs reg2 with mask and places the result in reg1.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro XORI32	reg1, reg2, mask
+.if \mask & 0xffff
+	.if \mask & 0xffff0000
+		xorhi	\reg1, \reg2, %hi(\mask)
+		xori	\reg1, \reg1, %lo(\mask)
+	.else
+		xori	\reg1, \reg2, %lo(\mask)
+	.endif
+.else
+	xorhi	\reg1, \reg2, %hi(\mask)
+.endif
+.endm
+
+/*
+ * This is a support macro for BTBZ & BTBNZ.  It checks
+ * the bit to make sure it is valid 32 value.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro BT	reg1, reg2, bit
+.if \bit > 31
+	.err
+.else
+	.if \bit < 16
+		andi	\reg1, \reg2, (1 << \bit)
+	.else
+		andhi	\reg1, \reg2, (1 << (\bit - 16))
+	.endif
+.endif
+.endm
+
+/*
+ * Tests the bit in reg2 and branches to label if the
+ * bit is zero.  The result of the bit test is stored in reg1.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTBZ	reg1, reg2, bit, label
+	BT	\reg1, \reg2, \bit
+	beq	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and branches to label if the
+ * bit is non-zero.  The result of the bit test is stored in reg1.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTBNZ	reg1, reg2, bit, label
+	BT	\reg1, \reg2, \bit
+	bne	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and then compliments the bit in reg2.
+ * The result of the bit test is stored in reg1.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTC	reg1, reg2, bit
+.if \bit > 31
+	.err
+.else
+	.if \bit < 16
+		andi	\reg1, \reg2, (1 << \bit)
+		xori	\reg2, \reg2, (1 << \bit)
+	.else
+		andhi	\reg1, \reg2, (1 << (\bit - 16))
+		xorhi	\reg2, \reg2, (1 << (\bit - 16))
+	.endif
+.endif
+.endm
+
+/*
+ * Tests the bit in reg2 and then sets the bit in reg2.
+ * The result of the bit test is stored in reg1.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTS	reg1, reg2, bit
+.if \bit > 31
+	.err
+.else
+	.if \bit < 16
+		andi	\reg1, \reg2, (1 << \bit)
+		ori	\reg2, \reg2, (1 << \bit)
+	.else
+		andhi	\reg1, \reg2, (1 << (\bit - 16))
+		orhi	\reg2, \reg2, (1 << (\bit - 16))
+	.endif
+.endif
+.endm
+
+/*
+ * Tests the bit in reg2 and then resets the bit in reg2.
+ * The result of the bit test is stored in reg1.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTR	reg1, reg2, bit
+.if \bit > 31
+	.err
+.else
+	.if \bit < 16
+		andi	\reg1, \reg2, (1 << \bit)
+		andi	\reg2, \reg2, %lo(~(1 << \bit))
+	.else
+		andhi	\reg1, \reg2, (1 << (\bit - 16))
+		andhi	\reg2, \reg2, %lo(~(1 << (\bit - 16)))
+	.endif
+.endif
+.endm
+
+/*
+ * Tests the bit in reg2 and then compliments the bit in reg2.
+ * The result of the bit test is stored in reg1.  If the
+ * original bit was zero it branches to label.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTCBZ	reg1, reg2, bit, label
+	BTC	\reg1, \reg2, \bit
+	beq	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and then compliments the bit in reg2.
+ * The result of the bit test is stored in reg1.  If the
+ * original bit was non-zero it branches to label.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTCBNZ	reg1, reg2, bit, label
+	BTC	\reg1, \reg2, \bit
+	bne	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and then sets the bit in reg2.
+ * The result of the bit test is stored in reg1.  If the
+ * original bit was zero it branches to label.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTSBZ	reg1, reg2, bit, label
+	BTS	\reg1, \reg2, \bit
+	beq	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and then sets the bit in reg2.
+ * The result of the bit test is stored in reg1.  If the
+ * original bit was non-zero it branches to label.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTSBNZ	reg1, reg2, bit, label
+	BTS	\reg1, \reg2, \bit
+	bne	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and then resets the bit in reg2.
+ * The result of the bit test is stored in reg1.  If the
+ * original bit was zero it branches to label.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTRBZ	reg1, reg2, bit, label
+	BTR	\reg1, \reg2, \bit
+	bne	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bit in reg2 and then resets the bit in reg2.
+ * The result of the bit test is stored in reg1.  If the
+ * original bit was non-zero it branches to label.
+ *
+ * It is NOT safe to use the same register for reg1 & reg2.
+ */
+
+.macro BTRBNZ	reg1, reg2, bit, label
+	BTR	\reg1, \reg2, \bit
+	bne	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bits in mask against reg2 stores the result in reg1.
+ * If the all the bits in the mask are zero it branches to label.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro TSTBZ	reg1, reg2, mask, label
+	ANDI32	\reg1, \reg2, \mask
+	beq	\reg1, r0, \label
+.endm
+
+/*
+ * Tests the bits in mask against reg2 stores the result in reg1.
+ * If the any of the bits in the mask are 1 it branches to label.
+ *
+ * It is safe to use the same register for reg1 & reg2.
+ */
+
+.macro TSTBNZ	reg1, reg2, mask, label
+	ANDI32	\reg1, \reg2, \mask
+	bne	\reg1, r0, \label
+.endm
+
+/*
+ * Pushes reg onto the stack.
+ */
+
+.macro PUSH	reg
+	addi	sp, sp, -4
+	stw	\reg, 0(sp)
+.endm
+
+/*
+ * Pops the top of the stack into reg.
+ */
+
+.macro POP	reg
+	ldw	\reg, 0(sp)
+	addi	sp, sp, 4
+.endm
+
+
+#endif /* _ASM_NIOS2_ASMMACROS_H */
diff --git a/arch/nios2/include/asm/asm-offsets.h b/arch/nios2/include/asm/asm-offsets.h
new file mode 100644
index 000000000..e51465213
--- /dev/null
+++ b/arch/nios2/include/asm/asm-offsets.h
@@ -0,0 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ *  Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ */
+
+#include <generated/asm-offsets.h>
diff --git a/arch/nios2/include/asm/cache.h b/arch/nios2/include/asm/cache.h
new file mode 100644
index 000000000..43695f341
--- /dev/null
+++ b/arch/nios2/include/asm/cache.h
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * All rights reserved.
+ */
+
+#ifndef _ASM_NIOS2_CACHE_H
+#define _ASM_NIOS2_CACHE_H
+
+#define NIOS2_DCACHE_SIZE	CONFIG_NIOS2_DCACHE_SIZE
+#define NIOS2_ICACHE_SIZE	CONFIG_NIOS2_ICACHE_SIZE
+#define NIOS2_DCACHE_LINE_SIZE	CONFIG_NIOS2_DCACHE_LINE_SIZE
+#define NIOS2_ICACHE_LINE_SHIFT	5
+#define NIOS2_ICACHE_LINE_SIZE	(1 << NIOS2_ICACHE_LINE_SHIFT)
+
+/* bytes per L1 cache line */
+#define L1_CACHE_SHIFT		NIOS2_ICACHE_LINE_SHIFT
+#define L1_CACHE_BYTES		NIOS2_ICACHE_LINE_SIZE
+
+#define ARCH_DMA_MINALIGN	L1_CACHE_BYTES
+
+#define __cacheline_aligned
+#define ____cacheline_aligned
+
+#endif
diff --git a/arch/nios2/include/asm/cacheflush.h b/arch/nios2/include/asm/cacheflush.h
new file mode 100644
index 000000000..d0b71dd71
--- /dev/null
+++ b/arch/nios2/include/asm/cacheflush.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2003 Microtronix Datacom Ltd.
+ * Copyright (C) 2000-2002 Greg Ungerer <gerg@snapgear.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_CACHEFLUSH_H
+#define _ASM_NIOS2_CACHEFLUSH_H
+
+#include <linux/mm_types.h>
+
+/*
+ * This flag is used to indicate that the page pointed to by a pte is clean
+ * and does not require cleaning before returning it to the user.
+ */
+#define PG_dcache_clean PG_arch_1
+
+struct mm_struct;
+
+extern void flush_cache_all(void);
+extern void flush_cache_mm(struct mm_struct *mm);
+extern void flush_cache_dup_mm(struct mm_struct *mm);
+extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
+	unsigned long end);
+extern void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
+	unsigned long pfn);
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
+void flush_dcache_page(struct page *page);
+
+extern void flush_icache_range(unsigned long start, unsigned long end);
+extern void flush_icache_page(struct vm_area_struct *vma, struct page *page);
+
+#define flush_cache_vmap(start, end)		flush_dcache_range(start, end)
+#define flush_cache_vunmap(start, end)		flush_dcache_range(start, end)
+
+extern void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+				unsigned long user_vaddr,
+				void *dst, void *src, int len);
+extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+				unsigned long user_vaddr,
+				void *dst, void *src, int len);
+
+extern void flush_dcache_range(unsigned long start, unsigned long end);
+extern void invalidate_dcache_range(unsigned long start, unsigned long end);
+
+#define flush_dcache_mmap_lock(mapping)		xa_lock_irq(&mapping->i_pages)
+#define flush_dcache_mmap_unlock(mapping)	xa_unlock_irq(&mapping->i_pages)
+
+#endif /* _ASM_NIOS2_CACHEFLUSH_H */
diff --git a/arch/nios2/include/asm/checksum.h b/arch/nios2/include/asm/checksum.h
new file mode 100644
index 000000000..69004e07a
--- /dev/null
+++ b/arch/nios2/include/asm/checksum.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS_CHECKSUM_H
+#define _ASM_NIOS_CHECKSUM_H
+
+/* Take these from lib/checksum.c */
+extern __wsum csum_partial(const void *buff, int len, __wsum sum);
+extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
+extern __sum16 ip_compute_csum(const void *buff, int len);
+
+/*
+ * Fold a partial checksum
+ */
+static inline __sum16 csum_fold(__wsum sum)
+{
+	__asm__ __volatile__(
+		"add	%0, %1, %0\n"
+		"cmpltu	r8, %0, %1\n"
+		"srli	%0, %0, 16\n"
+		"add	%0, %0, r8\n"
+		"nor	%0, %0, %0\n"
+		: "=r" (sum)
+		: "r" (sum << 16), "0" (sum)
+		: "r8");
+	return (__force __sum16) sum;
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+#define csum_tcpudp_nofold csum_tcpudp_nofold
+static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+					__u32 len, __u8 proto,
+					__wsum sum)
+{
+	__asm__ __volatile__(
+		"add	%0, %1, %0\n"
+		"cmpltu	r8, %0, %1\n"
+		"add	%0, %0, r8\n"	/* add carry */
+		"add	%0, %2, %0\n"
+		"cmpltu	r8, %0, %2\n"
+		"add	%0, %0, r8\n"	/* add carry */
+		"add	%0, %3, %0\n"
+		"cmpltu	r8, %0, %3\n"
+		"add	%0, %0, r8\n"	/* add carry */
+		: "=r" (sum), "=r" (saddr)
+		: "r" (daddr), "r" ((len + proto) << 8),
+		  "0" (sum),
+		  "1" (saddr)
+		: "r8");
+
+	return sum;
+}
+
+static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+					__u32 len, __u8 proto,
+					__wsum sum)
+{
+	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
+}
+
+#endif /* _ASM_NIOS_CHECKSUM_H */
diff --git a/arch/nios2/include/asm/cpuinfo.h b/arch/nios2/include/asm/cpuinfo.h
new file mode 100644
index 000000000..61349e003
--- /dev/null
+++ b/arch/nios2/include/asm/cpuinfo.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#ifndef _ASM_NIOS2_CPUINFO_H
+#define _ASM_NIOS2_CPUINFO_H
+
+#include <linux/types.h>
+
+struct cpuinfo {
+	/* Core CPU configuration */
+	char cpu_impl[12];
+	u32 cpu_clock_freq;
+	bool mmu;
+	bool has_div;
+	bool has_mul;
+	bool has_mulx;
+	bool has_bmx;
+	bool has_cdx;
+
+	/* CPU caches */
+	u32 icache_line_size;
+	u32 icache_size;
+	u32 dcache_line_size;
+	u32 dcache_size;
+
+	/* TLB */
+	u32 tlb_pid_num_bits;	/* number of bits used for the PID in TLBMISC */
+	u32 tlb_num_ways;
+	u32 tlb_num_ways_log2;
+	u32 tlb_num_entries;
+	u32 tlb_num_lines;
+	u32 tlb_ptr_sz;
+
+	/* Addresses */
+	u32 reset_addr;
+	u32 exception_addr;
+	u32 fast_tlb_miss_exc_addr;
+};
+
+extern struct cpuinfo cpuinfo;
+
+extern void setup_cpuinfo(void);
+
+#endif /* _ASM_NIOS2_CPUINFO_H */
diff --git a/arch/nios2/include/asm/delay.h b/arch/nios2/include/asm/delay.h
new file mode 100644
index 000000000..098e49bf3
--- /dev/null
+++ b/arch/nios2/include/asm/delay.h
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2014 Altera Corporation
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_DELAY_H
+#define _ASM_NIOS2_DELAY_H
+
+#include <asm-generic/delay.h>
+
+/* Undefined functions to get compile-time errors */
+extern void __bad_udelay(void);
+extern void __bad_ndelay(void);
+
+extern unsigned long loops_per_jiffy;
+
+#endif /* _ASM_NIOS2_DELAY_H */
diff --git a/arch/nios2/include/asm/elf.h b/arch/nios2/include/asm/elf.h
new file mode 100644
index 000000000..984dd6de1
--- /dev/null
+++ b/arch/nios2/include/asm/elf.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#ifndef _ASM_NIOS2_ELF_H
+#define _ASM_NIOS2_ELF_H
+
+#include <uapi/asm/elf.h>
+
+/*
+ * This is used to ensure we don't load something for the wrong architecture.
+ */
+#define elf_check_arch(x) ((x)->e_machine == EM_ALTERA_NIOS2)
+
+#define ELF_PLAT_INIT(_r, load_addr)
+
+#define CORE_DUMP_USE_REGSET
+#define ELF_EXEC_PAGESIZE	4096
+
+/* This is the location that an ET_DYN program is loaded if exec'ed.  Typical
+   use of this is to invoke "./ld.so someprog" to test out a new version of
+   the loader.  We need to make sure that it is out of the way of the program
+   that it will "exec", and that there is sufficient room for the brk.  */
+
+#define ELF_ET_DYN_BASE		0xD0000000UL
+
+/* regs is struct pt_regs, pr_reg is elf_gregset_t (which is
+   now struct_user_regs, they are different) */
+
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES	1
+struct linux_binprm;
+extern int arch_setup_additional_pages(struct linux_binprm *bprm,
+	int uses_interp);
+#define ELF_CORE_COPY_REGS(pr_reg, regs)				\
+{ do {									\
+	/* Bleech. */							\
+	pr_reg[0]  = regs->r8;						\
+	pr_reg[1]  = regs->r9;						\
+	pr_reg[2]  = regs->r10;						\
+	pr_reg[3]  = regs->r11;						\
+	pr_reg[4]  = regs->r12;						\
+	pr_reg[5]  = regs->r13;						\
+	pr_reg[6]  = regs->r14;						\
+	pr_reg[7]  = regs->r15;						\
+	pr_reg[8]  = regs->r1;						\
+	pr_reg[9]  = regs->r2;						\
+	pr_reg[10] = regs->r3;						\
+	pr_reg[11] = regs->r4;						\
+	pr_reg[12] = regs->r5;						\
+	pr_reg[13] = regs->r6;						\
+	pr_reg[14] = regs->r7;						\
+	pr_reg[15] = regs->orig_r2;					\
+	pr_reg[16] = regs->ra;						\
+	pr_reg[17] = regs->fp;						\
+	pr_reg[18] = regs->sp;						\
+	pr_reg[19] = regs->gp;						\
+	pr_reg[20] = regs->estatus;					\
+	pr_reg[21] = regs->ea;						\
+	pr_reg[22] = regs->orig_r7;					\
+	{								\
+		struct switch_stack *sw = ((struct switch_stack *)regs) - 1; \
+		pr_reg[23] = sw->r16;					\
+		pr_reg[24] = sw->r17;					\
+		pr_reg[25] = sw->r18;					\
+		pr_reg[26] = sw->r19;					\
+		pr_reg[27] = sw->r20;					\
+		pr_reg[28] = sw->r21;					\
+		pr_reg[29] = sw->r22;					\
+		pr_reg[30] = sw->r23;					\
+		pr_reg[31] = sw->fp;					\
+		pr_reg[32] = sw->gp;					\
+		pr_reg[33] = sw->ra;					\
+	}								\
+} while (0); }
+
+/* This yields a mask that user programs can use to figure out what
+   instruction set this cpu supports.  */
+
+#define ELF_HWCAP	(0)
+
+/* This yields a string that ld.so will use to load implementation
+   specific libraries for optimization.  This is more specific in
+   intent than poking at uname or /proc/cpuinfo.  */
+
+#define ELF_PLATFORM  (NULL)
+
+#endif /* _ASM_NIOS2_ELF_H */
diff --git a/arch/nios2/include/asm/entry.h b/arch/nios2/include/asm/entry.h
new file mode 100644
index 000000000..bafb7b2ca
--- /dev/null
+++ b/arch/nios2/include/asm/entry.h
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_ENTRY_H
+#define _ASM_NIOS2_ENTRY_H
+
+#ifdef __ASSEMBLY__
+
+#include <asm/processor.h>
+#include <asm/registers.h>
+#include <asm/asm-offsets.h>
+
+/*
+ * Standard Nios2 interrupt entry and exit macros.
+ * Must be called with interrupts disabled.
+ */
+.macro SAVE_ALL
+	rdctl	r24, estatus
+	andi	r24, r24, ESTATUS_EU
+	beq	r24, r0, 1f /* In supervisor mode, already on kernel stack */
+
+	movia	r24, _current_thread	/* Switch to current kernel stack */
+	ldw	r24, 0(r24)		/* using the thread_info */
+	addi	r24, r24, THREAD_SIZE-PT_REGS_SIZE
+	stw	sp, PT_SP(r24)		/* Save user stack before changing */
+	mov	sp, r24
+	br	2f
+
+1 :	mov	r24, sp
+	addi	sp, sp, -PT_REGS_SIZE	/* Backup the kernel stack pointer */
+	stw	r24, PT_SP(sp)
+2 :	stw	r1, PT_R1(sp)
+	stw	r2, PT_R2(sp)
+	stw	r3, PT_R3(sp)
+	stw	r4, PT_R4(sp)
+	stw	r5, PT_R5(sp)
+	stw	r6, PT_R6(sp)
+	stw	r7, PT_R7(sp)
+	stw	r8, PT_R8(sp)
+	stw	r9, PT_R9(sp)
+	stw	r10, PT_R10(sp)
+	stw	r11, PT_R11(sp)
+	stw	r12, PT_R12(sp)
+	stw	r13, PT_R13(sp)
+	stw	r14, PT_R14(sp)
+	stw	r15, PT_R15(sp)
+	movi	r24, -1
+	stw	r24, PT_ORIG_R2(sp)
+	stw	r7, PT_ORIG_R7(sp)
+
+	stw	ra, PT_RA(sp)
+	stw	fp, PT_FP(sp)
+	stw	gp, PT_GP(sp)
+	rdctl	r24, estatus
+	stw	r24, PT_ESTATUS(sp)
+	stw	ea, PT_EA(sp)
+.endm
+
+.macro RESTORE_ALL
+	ldw	r1, PT_R1(sp)		/* Restore registers */
+	ldw	r2, PT_R2(sp)
+	ldw	r3, PT_R3(sp)
+	ldw	r4, PT_R4(sp)
+	ldw	r5, PT_R5(sp)
+	ldw	r6, PT_R6(sp)
+	ldw	r7, PT_R7(sp)
+	ldw	r8, PT_R8(sp)
+	ldw	r9, PT_R9(sp)
+	ldw	r10, PT_R10(sp)
+	ldw	r11, PT_R11(sp)
+	ldw	r12, PT_R12(sp)
+	ldw	r13, PT_R13(sp)
+	ldw	r14, PT_R14(sp)
+	ldw	r15, PT_R15(sp)
+	ldw	ra, PT_RA(sp)
+	ldw	fp, PT_FP(sp)
+	ldw	gp, PT_GP(sp)
+	ldw	r24, PT_ESTATUS(sp)
+	wrctl	estatus, r24
+	ldw	ea, PT_EA(sp)
+	ldw	sp, PT_SP(sp)		/* Restore sp last */
+.endm
+
+.macro	SAVE_SWITCH_STACK
+	addi	sp, sp, -SWITCH_STACK_SIZE
+	stw	r16, SW_R16(sp)
+	stw	r17, SW_R17(sp)
+	stw	r18, SW_R18(sp)
+	stw	r19, SW_R19(sp)
+	stw	r20, SW_R20(sp)
+	stw	r21, SW_R21(sp)
+	stw	r22, SW_R22(sp)
+	stw	r23, SW_R23(sp)
+	stw	fp, SW_FP(sp)
+	stw	gp, SW_GP(sp)
+	stw	ra, SW_RA(sp)
+.endm
+
+.macro	RESTORE_SWITCH_STACK
+	ldw	r16, SW_R16(sp)
+	ldw	r17, SW_R17(sp)
+	ldw	r18, SW_R18(sp)
+	ldw	r19, SW_R19(sp)
+	ldw	r20, SW_R20(sp)
+	ldw	r21, SW_R21(sp)
+	ldw	r22, SW_R22(sp)
+	ldw	r23, SW_R23(sp)
+	ldw	fp, SW_FP(sp)
+	ldw	gp, SW_GP(sp)
+	ldw	ra, SW_RA(sp)
+	addi	sp, sp, SWITCH_STACK_SIZE
+.endm
+
+#endif /* __ASSEMBLY__ */
+#endif /* _ASM_NIOS2_ENTRY_H */
diff --git a/arch/nios2/include/asm/io.h b/arch/nios2/include/asm/io.h
new file mode 100644
index 000000000..746853ac7
--- /dev/null
+++ b/arch/nios2/include/asm/io.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2014 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_IO_H
+#define _ASM_NIOS2_IO_H
+
+#include <linux/types.h>
+#include <asm/pgtable-bits.h>
+
+/* PCI is not supported in nios2, set this to 0. */
+#define IO_SPACE_LIMIT 0
+
+#define readb_relaxed(addr)	readb(addr)
+#define readw_relaxed(addr)	readw(addr)
+#define readl_relaxed(addr)	readl(addr)
+
+#define writeb_relaxed(x, addr)	writeb(x, addr)
+#define writew_relaxed(x, addr)	writew(x, addr)
+#define writel_relaxed(x, addr)	writel(x, addr)
+
+void __iomem *ioremap(unsigned long physaddr, unsigned long size);
+void iounmap(void __iomem *addr);
+
+/* Pages to physical address... */
+#define page_to_phys(page)	virt_to_phys(page_to_virt(page))
+
+/* Macros used for converting between virtual and physical mappings. */
+#define phys_to_virt(vaddr)	\
+	((void *)((unsigned long)(vaddr) | CONFIG_NIOS2_KERNEL_REGION_BASE))
+/* Clear top 3 bits */
+#define virt_to_phys(vaddr)	\
+	((unsigned long)((unsigned long)(vaddr) & ~0xE0000000))
+
+#include <asm-generic/io.h>
+
+#endif /* _ASM_NIOS2_IO_H */
diff --git a/arch/nios2/include/asm/irq.h b/arch/nios2/include/asm/irq.h
new file mode 100644
index 000000000..c52c94884
--- /dev/null
+++ b/arch/nios2/include/asm/irq.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#ifndef _ASM_NIOS2_IRQ_H
+#define _ASM_NIOS2_IRQ_H
+
+#define NIOS2_CPU_NR_IRQS	32
+
+#include <asm-generic/irq.h>
+
+#endif
diff --git a/arch/nios2/include/asm/irqflags.h b/arch/nios2/include/asm/irqflags.h
new file mode 100644
index 000000000..25acf2786
--- /dev/null
+++ b/arch/nios2/include/asm/irqflags.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
+ */
+#ifndef _ASM_IRQFLAGS_H
+#define _ASM_IRQFLAGS_H
+
+#include <asm/registers.h>
+
+static inline unsigned long arch_local_save_flags(void)
+{
+	return RDCTL(CTL_FSTATUS);
+}
+
+/*
+ * This will restore ALL status register flags, not only the interrupt
+ * mask flag.
+ */
+static inline void arch_local_irq_restore(unsigned long flags)
+{
+	WRCTL(CTL_FSTATUS, flags);
+}
+
+static inline void arch_local_irq_disable(void)
+{
+	unsigned long flags;
+
+	flags = arch_local_save_flags();
+	arch_local_irq_restore(flags & ~STATUS_PIE);
+}
+
+static inline void arch_local_irq_enable(void)
+{
+	unsigned long flags;
+
+	flags = arch_local_save_flags();
+	arch_local_irq_restore(flags | STATUS_PIE);
+}
+
+static inline int arch_irqs_disabled_flags(unsigned long flags)
+{
+	return (flags & STATUS_PIE) == 0;
+}
+
+static inline int arch_irqs_disabled(void)
+{
+	return arch_irqs_disabled_flags(arch_local_save_flags());
+}
+
+static inline unsigned long arch_local_irq_save(void)
+{
+	unsigned long flags;
+
+	flags = arch_local_save_flags();
+	arch_local_irq_restore(flags & ~STATUS_PIE);
+	return flags;
+}
+
+#endif /* _ASM_IRQFLAGS_H */
diff --git a/arch/nios2/include/asm/kgdb.h b/arch/nios2/include/asm/kgdb.h
new file mode 100644
index 000000000..1fe8a6b35
--- /dev/null
+++ b/arch/nios2/include/asm/kgdb.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2015 Altera Corporation
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * Based on the code posted by Kazuyasu on the Altera Forum at:
+ * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20
+ */
+
+#ifndef _ASM_NIOS2_KGDB_H
+#define _ASM_NIOS2_KGDB_H
+
+#define CACHE_FLUSH_IS_SAFE	1
+#define BUFMAX			2048
+
+enum regnames {
+	GDB_R0 = 0,
+	GDB_AT,
+	GDB_R2,
+	GDB_R3,
+	GDB_R4,
+	GDB_R5,
+	GDB_R6,
+	GDB_R7,
+	GDB_R8,
+	GDB_R9,
+	GDB_R10,
+	GDB_R11,
+	GDB_R12,
+	GDB_R13,
+	GDB_R14,
+	GDB_R15,
+	GDB_R16,
+	GDB_R17,
+	GDB_R18,
+	GDB_R19,
+	GDB_R20,
+	GDB_R21,
+	GDB_R22,
+	GDB_R23,
+	GDB_ET,
+	GDB_BT,
+	GDB_GP,
+	GDB_SP,
+	GDB_FP,
+	GDB_EA,
+	GDB_BA,
+	GDB_RA,
+	GDB_PC,
+	GDB_STATUS,
+	GDB_ESTATUS,
+	GDB_BSTATUS,
+	GDB_IENABLE,
+	GDB_IPENDING,
+	GDB_CPUID,
+	GDB_CTL6,
+	GDB_EXCEPTION,
+	GDB_PTEADDR,
+	GDB_TLBACC,
+	GDB_TLBMISC,
+	GDB_ECCINJ,
+	GDB_BADADDR,
+	GDB_CONFIG,
+	GDB_MPUBASE,
+	GDB_MPUACC,
+	/* do not change the last entry or anything below! */
+	GDB_NUMREGBYTES		/* number of registers */
+};
+
+#define GDB_SIZEOF_REG		sizeof(u32)
+#define DBG_MAX_REG_NUM	(49)
+#define NUMREGBYTES		(DBG_MAX_REG_NUM * sizeof(GDB_SIZEOF_REG))
+
+#define BREAK_INSTR_SIZE	4
+static inline void arch_kgdb_breakpoint(void)
+{
+	__asm__ __volatile__("trap 30\n");
+}
+
+#endif /* _ASM_NIOS2_KGDB_H */
diff --git a/arch/nios2/include/asm/linkage.h b/arch/nios2/include/asm/linkage.h
new file mode 100644
index 000000000..211302301
--- /dev/null
+++ b/arch/nios2/include/asm/linkage.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * All rights reserved.
+ */
+
+#ifndef _ASM_NIOS2_LINKAGE_H
+#define _ASM_NIOS2_LINKAGE_H
+
+/* This file is required by include/linux/linkage.h */
+#define __ALIGN .align 4
+#define __ALIGN_STR ".align 4"
+
+#endif
diff --git a/arch/nios2/include/asm/mmu.h b/arch/nios2/include/asm/mmu.h
new file mode 100644
index 000000000..d9c0b1010
--- /dev/null
+++ b/arch/nios2/include/asm/mmu.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_MMU_H
+#define _ASM_NIOS2_MMU_H
+
+/* Default "unsigned long" context */
+typedef unsigned long mm_context_t;
+
+#endif /* _ASM_NIOS2_MMU_H */
diff --git a/arch/nios2/include/asm/mmu_context.h b/arch/nios2/include/asm/mmu_context.h
new file mode 100644
index 000000000..4f99ed09b
--- /dev/null
+++ b/arch/nios2/include/asm/mmu_context.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 1996, 1997, 1998, 1999 by Ralf Baechle
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ *
+ * based on MIPS asm/mmu_context.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_MMU_CONTEXT_H
+#define _ASM_NIOS2_MMU_CONTEXT_H
+
+#include <linux/mm_types.h>
+
+#include <asm-generic/mm_hooks.h>
+
+extern void mmu_context_init(void);
+extern unsigned long get_pid_from_context(mm_context_t *ctx);
+
+/*
+ * For the fast tlb miss handlers, we keep a pointer to the current pgd.
+ * processor.
+ */
+extern pgd_t *pgd_current;
+
+/*
+ * Initialize the context related info for a new mm_struct instance.
+ *
+ * Set all new contexts to 0, that way the generation will never match
+ * the currently running generation when this context is switched in.
+ */
+#define init_new_context init_new_context
+static inline int init_new_context(struct task_struct *tsk,
+					struct mm_struct *mm)
+{
+	mm->context = 0;
+	return 0;
+}
+
+void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+		struct task_struct *tsk);
+
+/*
+ * After we have set current->mm to a new value, this activates
+ * the context for the new mm so we see the new mappings.
+ */
+#define activate_mm activate_mm
+void activate_mm(struct mm_struct *prev, struct mm_struct *next);
+
+#include <asm-generic/mmu_context.h>
+
+#endif /* _ASM_NIOS2_MMU_CONTEXT_H */
diff --git a/arch/nios2/include/asm/page.h b/arch/nios2/include/asm/page.h
new file mode 100644
index 000000000..6a989819a
--- /dev/null
+++ b/arch/nios2/include/asm/page.h
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * MMU support based on asm/page.h from mips which is:
+ *
+ * Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_PAGE_H
+#define _ASM_NIOS2_PAGE_H
+
+#include <linux/pfn.h>
+#include <linux/const.h>
+
+/*
+ * PAGE_SHIFT determines the page size
+ */
+#define PAGE_SHIFT	12
+#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK	(~(PAGE_SIZE - 1))
+
+/*
+ * PAGE_OFFSET -- the first address of the first page of memory.
+ */
+#define PAGE_OFFSET	\
+	(CONFIG_NIOS2_MEM_BASE + CONFIG_NIOS2_KERNEL_REGION_BASE)
+
+#ifndef __ASSEMBLY__
+
+/*
+ * This gives the physical RAM offset.
+ */
+#define PHYS_OFFSET		CONFIG_NIOS2_MEM_BASE
+
+/*
+ * It's normally defined only for FLATMEM config but it's
+ * used in our early mem init code for all memory models.
+ * So always define it.
+ */
+#define ARCH_PFN_OFFSET		PFN_UP(PHYS_OFFSET)
+
+#define clear_page(page)	memset((page), 0, PAGE_SIZE)
+#define copy_page(to, from)	memcpy((to), (from), PAGE_SIZE)
+
+struct page;
+
+extern void clear_user_page(void *addr, unsigned long vaddr, struct page *page);
+extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
+				struct page *to);
+
+/*
+ * These are used to make use of C type-checking.
+ */
+typedef struct page *pgtable_t;
+typedef struct { unsigned long pte; } pte_t;
+typedef struct { unsigned long pgd; } pgd_t;
+typedef struct { unsigned long pgprot; } pgprot_t;
+
+#define pte_val(x)	((x).pte)
+#define pgd_val(x)	((x).pgd)
+#define pgprot_val(x)	((x).pgprot)
+
+#define __pte(x)	((pte_t) { (x) })
+#define __pgd(x)	((pgd_t) { (x) })
+#define __pgprot(x)	((pgprot_t) { (x) })
+
+extern unsigned long memory_start;
+extern unsigned long memory_end;
+extern unsigned long memory_size;
+
+extern struct page *mem_map;
+
+# define __pa(x)		\
+	((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
+# define __va(x)		\
+	((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
+
+#define page_to_virt(page)	\
+	((void *)(((page) - mem_map) << PAGE_SHIFT) + PAGE_OFFSET)
+
+# define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
+
+static inline bool pfn_valid(unsigned long pfn)
+{
+	/* avoid <linux/mm.h> include hell */
+	extern unsigned long max_mapnr;
+	unsigned long pfn_offset = ARCH_PFN_OFFSET;
+
+	return pfn >= pfn_offset && pfn < max_mapnr;
+}
+
+# define virt_to_page(vaddr)	pfn_to_page(PFN_DOWN(virt_to_phys(vaddr)))
+# define virt_addr_valid(vaddr)	pfn_valid(PFN_DOWN(virt_to_phys(vaddr)))
+
+# define VM_DATA_DEFAULT_FLAGS	VM_DATA_FLAGS_NON_EXEC
+
+#include <asm-generic/memory_model.h>
+
+#include <asm-generic/getorder.h>
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_NIOS2_PAGE_H */
diff --git a/arch/nios2/include/asm/pgalloc.h b/arch/nios2/include/asm/pgalloc.h
new file mode 100644
index 000000000..3c4ae74d5
--- /dev/null
+++ b/arch/nios2/include/asm/pgalloc.h
@@ -0,0 +1,42 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994 - 2001, 2003 by Ralf Baechle
+ * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
+ */
+
+#ifndef _ASM_NIOS2_PGALLOC_H
+#define _ASM_NIOS2_PGALLOC_H
+
+#include <linux/mm.h>
+
+#include <asm-generic/pgalloc.h>
+
+static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
+	pte_t *pte)
+{
+	set_pmd(pmd, __pmd((unsigned long)pte));
+}
+
+static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
+	pgtable_t pte)
+{
+	set_pmd(pmd, __pmd((unsigned long)page_address(pte)));
+}
+
+/*
+ * Initialize a new pmd table with invalid pointers.
+ */
+extern void pmd_init(unsigned long page, unsigned long pagetable);
+
+extern pgd_t *pgd_alloc(struct mm_struct *mm);
+
+#define __pte_free_tlb(tlb, pte, addr)				\
+	do {							\
+		pgtable_pte_page_dtor(pte);			\
+		tlb_remove_page((tlb), (pte));			\
+	} while (0)
+
+#endif /* _ASM_NIOS2_PGALLOC_H */
diff --git a/arch/nios2/include/asm/pgtable-bits.h b/arch/nios2/include/asm/pgtable-bits.h
new file mode 100644
index 000000000..bfddff383
--- /dev/null
+++ b/arch/nios2/include/asm/pgtable-bits.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_PGTABLE_BITS_H
+#define _ASM_NIOS2_PGTABLE_BITS_H
+
+/*
+ * These are actual hardware defined protection bits in the tlbacc register
+ * which looks like this:
+ *
+ * 31 30 ... 26 25 24 23 22 21 20 19 18 ...  1  0
+ * ignored........  C  R  W  X  G PFN............
+ */
+#define _PAGE_GLOBAL	(1<<20)
+#define _PAGE_EXEC	(1<<21)
+#define _PAGE_WRITE	(1<<22)
+#define _PAGE_READ	(1<<23)
+#define _PAGE_CACHED	(1<<24)	/* C: data access cacheable */
+
+/*
+ * Software defined bits. They are ignored by the hardware and always read back
+ * as zero, but can be written as non-zero.
+ */
+#define _PAGE_PRESENT	(1<<25)	/* PTE contains a translation */
+#define _PAGE_ACCESSED	(1<<26)	/* page referenced */
+#define _PAGE_DIRTY	(1<<27)	/* dirty page */
+
+#endif /* _ASM_NIOS2_PGTABLE_BITS_H */
diff --git a/arch/nios2/include/asm/pgtable.h b/arch/nios2/include/asm/pgtable.h
new file mode 100644
index 000000000..b3d45e815
--- /dev/null
+++ b/arch/nios2/include/asm/pgtable.h
@@ -0,0 +1,260 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *
+ * Based on asm/pgtable-32.h from mips which is:
+ *
+ * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
+ * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_PGTABLE_H
+#define _ASM_NIOS2_PGTABLE_H
+
+#include <linux/io.h>
+#include <linux/bug.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+#include <asm/pgtable-bits.h>
+#include <asm-generic/pgtable-nopmd.h>
+
+#define VMALLOC_START		CONFIG_NIOS2_KERNEL_MMU_REGION_BASE
+#define VMALLOC_END		(CONFIG_NIOS2_KERNEL_REGION_BASE - 1)
+
+struct mm_struct;
+
+/* Helper macro */
+#define MKP(x, w, r) __pgprot(_PAGE_PRESENT | _PAGE_CACHED |		\
+				((x) ? _PAGE_EXEC : 0) |		\
+				((r) ? _PAGE_READ : 0) |		\
+				((w) ? _PAGE_WRITE : 0))
+/*
+ * These are the macros that generic kernel code needs
+ * (to populate protection_map[])
+ */
+
+/* Remove W bit on private pages for COW support */
+
+/* Shared pages can have exact HW mapping */
+
+/* Used all over the kernel */
+#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
+			     _PAGE_WRITE | _PAGE_EXEC | _PAGE_GLOBAL)
+
+#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_CACHED | _PAGE_READ | \
+			     _PAGE_WRITE | _PAGE_ACCESSED)
+
+#define PAGE_COPY MKP(0, 0, 1)
+
+#define PTRS_PER_PGD	(PAGE_SIZE / sizeof(pgd_t))
+#define PTRS_PER_PTE	(PAGE_SIZE / sizeof(pte_t))
+
+#define USER_PTRS_PER_PGD	\
+	(CONFIG_NIOS2_KERNEL_MMU_REGION_BASE / PGDIR_SIZE)
+
+#define PGDIR_SHIFT	22
+#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
+#define PGDIR_MASK	(~(PGDIR_SIZE-1))
+
+/*
+ * ZERO_PAGE is a global shared page that is always zero: used
+ * for zero-mapped memory areas etc..
+ */
+extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
+#define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern pte_t invalid_pte_table[PAGE_SIZE/sizeof(pte_t)];
+
+/*
+ * (pmds are folded into puds so this doesn't get actually called,
+ * but the define is needed for a generic inline function.)
+ */
+static inline void set_pmd(pmd_t *pmdptr, pmd_t pmdval)
+{
+	*pmdptr = pmdval;
+}
+
+static inline int pte_write(pte_t pte)		\
+	{ return pte_val(pte) & _PAGE_WRITE; }
+static inline int pte_dirty(pte_t pte)		\
+	{ return pte_val(pte) & _PAGE_DIRTY; }
+static inline int pte_young(pte_t pte)		\
+	{ return pte_val(pte) & _PAGE_ACCESSED; }
+
+#define pgprot_noncached pgprot_noncached
+
+static inline pgprot_t pgprot_noncached(pgprot_t _prot)
+{
+	unsigned long prot = pgprot_val(_prot);
+
+	prot &= ~_PAGE_CACHED;
+
+	return __pgprot(prot);
+}
+
+static inline int pte_none(pte_t pte)
+{
+	return !(pte_val(pte) & ~(_PAGE_GLOBAL|0xf));
+}
+
+static inline int pte_present(pte_t pte)	\
+	{ return pte_val(pte) & _PAGE_PRESENT; }
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+	pte_val(pte) &= ~_PAGE_WRITE;
+	return pte;
+}
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+	pte_val(pte) &= ~_PAGE_DIRTY;
+	return pte;
+}
+
+static inline pte_t pte_mkold(pte_t pte)
+{
+	pte_val(pte) &= ~_PAGE_ACCESSED;
+	return pte;
+}
+
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+	pte_val(pte) |= _PAGE_WRITE;
+	return pte;
+}
+
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+	pte_val(pte) |= _PAGE_DIRTY;
+	return pte;
+}
+
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+	pte_val(pte) |= _PAGE_ACCESSED;
+	return pte;
+}
+
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+	const unsigned long mask = _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC;
+
+	pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
+	return pte;
+}
+
+static inline int pmd_present(pmd_t pmd)
+{
+	return (pmd_val(pmd) != (unsigned long) invalid_pte_table)
+			&& (pmd_val(pmd) != 0UL);
+}
+
+static inline void pmd_clear(pmd_t *pmdp)
+{
+	pmd_val(*pmdp) = (unsigned long) invalid_pte_table;
+}
+
+#define pte_pfn(pte)		(pte_val(pte) & 0xfffff)
+#define pfn_pte(pfn, prot)	(__pte(pfn | pgprot_val(prot)))
+#define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
+
+/*
+ * Store a linux PTE into the linux page table.
+ */
+static inline void set_pte(pte_t *ptep, pte_t pteval)
+{
+	*ptep = pteval;
+}
+
+static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
+			      pte_t *ptep, pte_t pteval)
+{
+	unsigned long paddr = (unsigned long)page_to_virt(pte_page(pteval));
+
+	flush_dcache_range(paddr, paddr + PAGE_SIZE);
+	set_pte(ptep, pteval);
+}
+
+static inline int pmd_none(pmd_t pmd)
+{
+	return (pmd_val(pmd) ==
+		(unsigned long) invalid_pte_table) || (pmd_val(pmd) == 0UL);
+}
+
+#define pmd_bad(pmd)	(pmd_val(pmd) & ~PAGE_MASK)
+
+static inline void pte_clear(struct mm_struct *mm,
+				unsigned long addr, pte_t *ptep)
+{
+	pte_t null;
+
+	pte_val(null) = (addr >> PAGE_SHIFT) & 0xf;
+
+	set_pte_at(mm, addr, ptep, null);
+}
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+#define mk_pte(page, prot)	(pfn_pte(page_to_pfn(page), prot))
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+#define pmd_phys(pmd)		virt_to_phys((void *)pmd_val(pmd))
+#define pmd_pfn(pmd)		(pmd_phys(pmd) >> PAGE_SHIFT)
+#define pmd_page(pmd)		(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
+
+static inline unsigned long pmd_page_vaddr(pmd_t pmd)
+{
+	return pmd_val(pmd);
+}
+
+#define pte_ERROR(e) \
+	pr_err("%s:%d: bad pte %08lx.\n", \
+		__FILE__, __LINE__, pte_val(e))
+#define pgd_ERROR(e) \
+	pr_err("%s:%d: bad pgd %08lx.\n", \
+		__FILE__, __LINE__, pgd_val(e))
+
+/*
+ * Encode and decode a swap entry (must be !pte_none(pte) && !pte_present(pte):
+ *
+ * 31 30 29 28 27 26 25 24 23 22 21 20 19 18 ...  1  0
+ *  0  0  0  0 type.  0  0  0  0  0  0 offset.........
+ *
+ * This gives us up to 2**2 = 4 swap files and 2**20 * 4K = 4G per swap file.
+ *
+ * Note that the offset field is always non-zero, thus !pte_none(pte) is always
+ * true.
+ */
+#define __swp_type(swp)		(((swp).val >> 26) & 0x3)
+#define __swp_offset(swp)	((swp).val & 0xfffff)
+#define __swp_entry(type, off)	((swp_entry_t) { (((type) & 0x3) << 26) \
+						 | ((off) & 0xfffff) })
+#define __swp_entry_to_pte(swp)	((pte_t) { (swp).val })
+#define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
+
+#define kern_addr_valid(addr)		(1)
+
+extern void __init paging_init(void);
+extern void __init mmu_init(void);
+
+extern void update_mmu_cache(struct vm_area_struct *vma,
+			     unsigned long address, pte_t *pte);
+
+#endif /* _ASM_NIOS2_PGTABLE_H */
diff --git a/arch/nios2/include/asm/processor.h b/arch/nios2/include/asm/processor.h
new file mode 100644
index 000000000..8916d93d5
--- /dev/null
+++ b/arch/nios2/include/asm/processor.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ * Copyright (C) 2001 Ken Hill (khill@microtronix.com)
+ *                    Vic Phillips (vic@microtronix.com)
+ *
+ * based on SPARC asm/processor_32.h which is:
+ *
+ * Copyright (C) 1994 David S. Miller
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_PROCESSOR_H
+#define _ASM_NIOS2_PROCESSOR_H
+
+#include <asm/ptrace.h>
+#include <asm/registers.h>
+#include <asm/page.h>
+
+#define NIOS2_FLAG_KTHREAD	0x00000001	/* task is a kernel thread */
+
+#define NIOS2_OP_NOP		0x1883a
+#define NIOS2_OP_BREAK		0x3da03a
+
+#ifdef __KERNEL__
+
+#define STACK_TOP	TASK_SIZE
+#define STACK_TOP_MAX	STACK_TOP
+
+#endif /* __KERNEL__ */
+
+/* Kuser helpers is mapped to this user space address */
+#define KUSER_BASE		0x1000
+#define KUSER_SIZE		(PAGE_SIZE)
+#ifndef __ASSEMBLY__
+
+# define TASK_SIZE		0x7FFF0000UL
+# define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 3))
+
+/* The Nios processor specific thread struct. */
+struct thread_struct {
+	struct pt_regs *kregs;
+
+	/* Context switch saved kernel state. */
+	unsigned long ksp;
+	unsigned long kpsr;
+};
+
+#define INIT_MMAP \
+	{ &init_mm, (0), (0), __pgprot(0x0), VM_READ | VM_WRITE | VM_EXEC }
+
+# define INIT_THREAD {			\
+	.kregs	= NULL,			\
+	.ksp	= 0,			\
+	.kpsr	= 0,			\
+}
+
+extern void start_thread(struct pt_regs *regs, unsigned long pc,
+			unsigned long sp);
+
+struct task_struct;
+
+extern unsigned long __get_wchan(struct task_struct *p);
+
+#define task_pt_regs(p) \
+	((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
+
+/* Used by procfs */
+#define KSTK_EIP(tsk)	((tsk)->thread.kregs->ea)
+#define KSTK_ESP(tsk)	((tsk)->thread.kregs->sp)
+
+#define cpu_relax()	barrier()
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_NIOS2_PROCESSOR_H */
diff --git a/arch/nios2/include/asm/ptrace.h b/arch/nios2/include/asm/ptrace.h
new file mode 100644
index 000000000..9da34c302
--- /dev/null
+++ b/arch/nios2/include/asm/ptrace.h
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * based on m68k asm/processor.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_PTRACE_H
+#define _ASM_NIOS2_PTRACE_H
+
+#include <uapi/asm/ptrace.h>
+
+/* This struct defines the way the registers are stored on the
+   stack during a system call.  */
+
+#ifndef __ASSEMBLY__
+struct pt_regs {
+	unsigned long  r8;	/* r8-r15 Caller-saved GP registers */
+	unsigned long  r9;
+	unsigned long  r10;
+	unsigned long  r11;
+	unsigned long  r12;
+	unsigned long  r13;
+	unsigned long  r14;
+	unsigned long  r15;
+	unsigned long  r1;	/* Assembler temporary */
+	unsigned long  r2;	/* Retval LS 32bits */
+	unsigned long  r3;	/* Retval MS 32bits */
+	unsigned long  r4;	/* r4-r7 Register arguments */
+	unsigned long  r5;
+	unsigned long  r6;
+	unsigned long  r7;
+	unsigned long  orig_r2;	/* Copy of r2 ?? */
+	unsigned long  ra;	/* Return address */
+	unsigned long  fp;	/* Frame pointer */
+	unsigned long  sp;	/* Stack pointer */
+	unsigned long  gp;	/* Global pointer */
+	unsigned long  estatus;
+	unsigned long  ea;	/* Exception return address (pc) */
+	unsigned long  orig_r7;
+};
+
+/*
+ * This is the extended stack used by signal handlers and the context
+ * switcher: it's pushed after the normal "struct pt_regs".
+ */
+struct switch_stack {
+	unsigned long  r16;	/* r16-r23 Callee-saved GP registers */
+	unsigned long  r17;
+	unsigned long  r18;
+	unsigned long  r19;
+	unsigned long  r20;
+	unsigned long  r21;
+	unsigned long  r22;
+	unsigned long  r23;
+	unsigned long  fp;
+	unsigned long  gp;
+	unsigned long  ra;
+};
+
+#define user_mode(regs)	(((regs)->estatus & ESTATUS_EU))
+
+#define instruction_pointer(regs)	((regs)->ra)
+#define profile_pc(regs)		instruction_pointer(regs)
+#define user_stack_pointer(regs)	((regs)->sp)
+extern void show_regs(struct pt_regs *);
+
+#define current_pt_regs() \
+	((struct pt_regs *)((unsigned long)current_thread_info() + THREAD_SIZE)\
+		- 1)
+
+#define force_successful_syscall_return() (current_pt_regs()->orig_r2 = -1)
+
+int do_syscall_trace_enter(void);
+void do_syscall_trace_exit(void);
+#endif /* __ASSEMBLY__ */
+#endif /* _ASM_NIOS2_PTRACE_H */
diff --git a/arch/nios2/include/asm/registers.h b/arch/nios2/include/asm/registers.h
new file mode 100644
index 000000000..95b67dd16
--- /dev/null
+++ b/arch/nios2/include/asm/registers.h
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#ifndef _ASM_NIOS2_REGISTERS_H
+#define _ASM_NIOS2_REGISTERS_H
+
+#ifndef __ASSEMBLY__
+#include <asm/cpuinfo.h>
+#endif
+
+/* control register numbers */
+#define CTL_FSTATUS	0
+#define CTL_ESTATUS	1
+#define CTL_BSTATUS	2
+#define CTL_IENABLE	3
+#define CTL_IPENDING	4
+#define CTL_CPUID	5
+#define CTL_RSV1	6
+#define CTL_EXCEPTION	7
+#define CTL_PTEADDR	8
+#define CTL_TLBACC	9
+#define CTL_TLBMISC	10
+#define CTL_RSV2	11
+#define CTL_BADADDR	12
+#define CTL_CONFIG	13
+#define CTL_MPUBASE	14
+#define CTL_MPUACC	15
+
+/* access control registers using GCC builtins */
+#define RDCTL(r)	__builtin_rdctl(r)
+#define WRCTL(r, v)	__builtin_wrctl(r, v)
+
+/* status register bits */
+#define STATUS_PIE	(1 << 0)	/* processor interrupt enable */
+#define STATUS_U	(1 << 1)	/* user mode */
+#define STATUS_EH	(1 << 2)	/* Exception mode */
+
+/* estatus register bits */
+#define ESTATUS_EPIE	(1 << 0)	/* processor interrupt enable */
+#define ESTATUS_EU	(1 << 1)	/* user mode */
+#define ESTATUS_EH	(1 << 2)	/* Exception mode */
+
+/* tlbmisc register bits */
+#define TLBMISC_PID_SHIFT	4
+#ifndef __ASSEMBLY__
+#define TLBMISC_PID_MASK	((1UL << cpuinfo.tlb_pid_num_bits) - 1)
+#endif
+#define TLBMISC_WAY_MASK	0xf
+#define TLBMISC_WAY_SHIFT	20
+
+#define TLBMISC_PID	(TLBMISC_PID_MASK << TLBMISC_PID_SHIFT)	/* TLB PID */
+#define TLBMISC_WE	(1 << 18)	/* TLB write enable */
+#define TLBMISC_RD	(1 << 19)	/* TLB read */
+#define TLBMISC_WAY	(TLBMISC_WAY_MASK << TLBMISC_WAY_SHIFT) /* TLB way */
+
+#endif /* _ASM_NIOS2_REGISTERS_H */
diff --git a/arch/nios2/include/asm/setup.h b/arch/nios2/include/asm/setup.h
new file mode 100644
index 000000000..908a1526d
--- /dev/null
+++ b/arch/nios2/include/asm/setup.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#ifndef _ASM_NIOS2_SETUP_H
+#define _ASM_NIOS2_SETUP_H
+
+#include <asm-generic/setup.h>
+
+#ifndef __ASSEMBLY__
+#ifdef __KERNEL__
+
+extern char exception_handler_hook[];
+extern char fast_handler[];
+extern char fast_handler_end[];
+
+extern void pagetable_init(void);
+
+#endif/* __KERNEL__ */
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_NIOS2_SETUP_H */
diff --git a/arch/nios2/include/asm/shmparam.h b/arch/nios2/include/asm/shmparam.h
new file mode 100644
index 000000000..4288844ee
--- /dev/null
+++ b/arch/nios2/include/asm/shmparam.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright Altera Corporation (C) <2015>. All rights reserved
+ */
+#ifndef _ASM_NIOS2_SHMPARAM_H
+#define _ASM_NIOS2_SHMPARAM_H
+
+#define	SHMLBA	CONFIG_NIOS2_DCACHE_SIZE
+
+#endif /* _ASM_NIOS2_SHMPARAM_H */
diff --git a/arch/nios2/include/asm/string.h b/arch/nios2/include/asm/string.h
new file mode 100644
index 000000000..14dd570d6
--- /dev/null
+++ b/arch/nios2/include/asm/string.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_STRING_H
+#define _ASM_NIOS2_STRING_H
+
+#ifdef __KERNEL__
+
+#define __HAVE_ARCH_MEMSET
+#define __HAVE_ARCH_MEMCPY
+#define __HAVE_ARCH_MEMMOVE
+
+extern void *memset(void *s, int c, size_t count);
+extern void *memcpy(void *d, const void *s, size_t count);
+extern void *memmove(void *d, const void *s, size_t count);
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_NIOS2_STRING_H */
diff --git a/arch/nios2/include/asm/switch_to.h b/arch/nios2/include/asm/switch_to.h
new file mode 100644
index 000000000..c47b3f4af
--- /dev/null
+++ b/arch/nios2/include/asm/switch_to.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#ifndef _ASM_NIOS2_SWITCH_TO_H
+#define _ASM_NIOS2_SWITCH_TO_H
+
+/*
+ * switch_to(n) should switch tasks to task ptr, first checking that
+ * ptr isn't the current task, in which case it does nothing.  This
+ * also clears the TS-flag if the task we switched to has used the
+ * math co-processor latest.
+ */
+#define switch_to(prev, next, last)			\
+{							\
+	void *_last;					\
+	__asm__ __volatile__ (				\
+		"mov	r4, %1\n"			\
+		"mov	r5, %2\n"			\
+		"call	resume\n"			\
+		"mov	%0,r4\n"			\
+		: "=r" (_last)				\
+		: "r" (prev), "r" (next)		\
+		: "r4", "r5", "r7", "r8", "ra");	\
+	(last) = _last;					\
+}
+
+#endif /* _ASM_NIOS2_SWITCH_TO_H */
diff --git a/arch/nios2/include/asm/syscall.h b/arch/nios2/include/asm/syscall.h
new file mode 100644
index 000000000..fff52205f
--- /dev/null
+++ b/arch/nios2/include/asm/syscall.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright Altera Corporation (C) <2014>. All rights reserved
+ */
+
+#ifndef __ASM_NIOS2_SYSCALL_H__
+#define __ASM_NIOS2_SYSCALL_H__
+
+#include <uapi/linux/audit.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+
+static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
+{
+	return regs->r2;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+				struct pt_regs *regs)
+{
+	regs->r2 = regs->orig_r2;
+	regs->r7 = regs->orig_r7;
+}
+
+static inline long syscall_get_error(struct task_struct *task,
+				struct pt_regs *regs)
+{
+	return regs->r7 ? regs->r2 : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+	struct pt_regs *regs)
+{
+	return regs->r2;
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+	struct pt_regs *regs, int error, long val)
+{
+	if (error) {
+		/* error < 0, but nios2 uses > 0 return value */
+		regs->r2 = -error;
+		regs->r7 = 1;
+	} else {
+		regs->r2 = val;
+		regs->r7 = 0;
+	}
+}
+
+static inline void syscall_get_arguments(struct task_struct *task,
+	struct pt_regs *regs, unsigned long *args)
+{
+	*args++ = regs->r4;
+	*args++ = regs->r5;
+	*args++ = regs->r6;
+	*args++ = regs->r7;
+	*args++ = regs->r8;
+	*args   = regs->r9;
+}
+
+static inline int syscall_get_arch(struct task_struct *task)
+{
+	return AUDIT_ARCH_NIOS2;
+}
+
+#endif
diff --git a/arch/nios2/include/asm/syscalls.h b/arch/nios2/include/asm/syscalls.h
new file mode 100644
index 000000000..b4d4ed3bf
--- /dev/null
+++ b/arch/nios2/include/asm/syscalls.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright Altera Corporation (C) 2013. All rights reserved
+ */
+#ifndef __ASM_NIOS2_SYSCALLS_H
+#define __ASM_NIOS2_SYSCALLS_H
+
+int sys_cacheflush(unsigned long addr, unsigned long len,
+				unsigned int op);
+
+#include <asm-generic/syscalls.h>
+
+#endif /* __ASM_NIOS2_SYSCALLS_H */
diff --git a/arch/nios2/include/asm/thread_info.h b/arch/nios2/include/asm/thread_info.h
new file mode 100644
index 000000000..bcc0e9915
--- /dev/null
+++ b/arch/nios2/include/asm/thread_info.h
@@ -0,0 +1,104 @@
+/*
+ * NiosII low-level thread information
+ *
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * Based on asm/thread_info_no.h from m68k which is:
+ *
+ * Copyright (C) 2002 David Howells <dhowells@redhat.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_THREAD_INFO_H
+#define _ASM_NIOS2_THREAD_INFO_H
+
+#ifdef __KERNEL__
+
+/*
+ * Size of the kernel stack for each process.
+ */
+#define THREAD_SIZE_ORDER	1
+#define THREAD_SIZE		8192 /* 2 * PAGE_SIZE */
+
+#ifndef __ASSEMBLY__
+
+/*
+ * low level task data that entry.S needs immediate access to
+ * - this struct should fit entirely inside of one cache line
+ * - this struct shares the supervisor stack pages
+ * - if the contents of this structure are changed, the assembly constants
+ *   must also be changed
+ */
+struct thread_info {
+	struct task_struct	*task;		/* main task structure */
+	unsigned long		flags;		/* low level flags */
+	__u32			cpu;		/* current CPU */
+	int			preempt_count;	/* 0 => preemptable,<0 => BUG */
+	struct pt_regs		*regs;
+};
+
+/*
+ * macros/functions for gaining access to the thread information structure
+ *
+ * preempt_count needs to be 1 initially, until the scheduler is functional.
+ */
+#define INIT_THREAD_INFO(tsk)			\
+{						\
+	.task		= &tsk,			\
+	.flags		= 0,			\
+	.cpu		= 0,			\
+	.preempt_count	= INIT_PREEMPT_COUNT,	\
+}
+
+/* how to get the thread information struct from C */
+static inline struct thread_info *current_thread_info(void)
+{
+	register unsigned long sp asm("sp");
+
+	return (struct thread_info *)(sp & ~(THREAD_SIZE - 1));
+}
+#endif /* !__ASSEMBLY__ */
+
+/*
+ * thread information flags
+ * - these are process state flags that various assembly files may need to
+ *   access
+ * - pending work-to-be-done flags are in LSW
+ * - other flags in MSW
+ */
+#define TIF_SYSCALL_TRACE	0	/* syscall trace active */
+#define TIF_NOTIFY_RESUME	1	/* resumption notification requested */
+#define TIF_SIGPENDING		2	/* signal pending */
+#define TIF_NEED_RESCHED	3	/* rescheduling necessary */
+#define TIF_MEMDIE		4	/* is terminating due to OOM killer */
+#define TIF_SECCOMP		5	/* secure computing */
+#define TIF_SYSCALL_AUDIT	6	/* syscall auditing active */
+#define TIF_NOTIFY_SIGNAL	7	/* signal notifications exist */
+#define TIF_RESTORE_SIGMASK	9	/* restore signal mask in do_signal() */
+
+#define TIF_POLLING_NRFLAG	16	/* true if poll_idle() is polling
+					   TIF_NEED_RESCHED */
+
+#define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)
+#define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)
+#define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
+#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
+#define _TIF_SECCOMP		(1 << TIF_SECCOMP)
+#define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)
+#define _TIF_NOTIFY_SIGNAL	(1 << TIF_NOTIFY_SIGNAL)
+#define _TIF_RESTORE_SIGMASK	(1 << TIF_RESTORE_SIGMASK)
+#define _TIF_POLLING_NRFLAG	(1 << TIF_POLLING_NRFLAG)
+
+/* work to do on interrupt/exception return */
+#define _TIF_WORK_MASK		0x0000FFFE
+
+/* work to do on any return to u-space */
+# define _TIF_ALLWORK_MASK	0x0000FFFF
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_NIOS2_THREAD_INFO_H */
diff --git a/arch/nios2/include/asm/timex.h b/arch/nios2/include/asm/timex.h
new file mode 100644
index 000000000..40a1adc9b
--- /dev/null
+++ b/arch/nios2/include/asm/timex.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright Altera Corporation (C) 2014. All rights reserved.
+ */
+
+#ifndef _ASM_NIOS2_TIMEX_H
+#define _ASM_NIOS2_TIMEX_H
+
+typedef unsigned long cycles_t;
+
+extern cycles_t get_cycles(void);
+#define get_cycles get_cycles
+
+#define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback())
+
+#endif
diff --git a/arch/nios2/include/asm/tlb.h b/arch/nios2/include/asm/tlb.h
new file mode 100644
index 000000000..f9f2e27e3
--- /dev/null
+++ b/arch/nios2/include/asm/tlb.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_TLB_H
+#define _ASM_NIOS2_TLB_H
+
+extern void set_mmu_pid(unsigned long pid);
+
+/*
+ * NIOS32 does have flush_tlb_range(), but it lacks a limit and fallback to
+ * full mm invalidation. So use flush_tlb_mm() for everything.
+ */
+
+#include <linux/pagemap.h>
+#include <asm-generic/tlb.h>
+
+#endif /* _ASM_NIOS2_TLB_H */
diff --git a/arch/nios2/include/asm/tlbflush.h b/arch/nios2/include/asm/tlbflush.h
new file mode 100644
index 000000000..362d6da09
--- /dev/null
+++ b/arch/nios2/include/asm/tlbflush.h
@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#ifndef _ASM_NIOS2_TLBFLUSH_H
+#define _ASM_NIOS2_TLBFLUSH_H
+
+struct mm_struct;
+
+/*
+ * TLB flushing:
+ *
+ *  - flush_tlb_all() flushes all processes TLB entries
+ *  - flush_tlb_mm(mm) flushes the specified mm context TLB entries
+ *  - flush_tlb_range(vma, start, end) flushes a range of pages
+ *  - flush_tlb_page(vma, address) flushes a page
+ *  - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
+ *  - flush_tlb_kernel_page(address) flushes a kernel page
+ *
+ *  - reload_tlb_page(vma, address, pte) flushes the TLB for address like
+ *    flush_tlb_page, then replaces it with a TLB for pte.
+ */
+extern void flush_tlb_all(void);
+extern void flush_tlb_mm(struct mm_struct *mm);
+extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+			    unsigned long end);
+extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
+
+static inline void flush_tlb_page(struct vm_area_struct *vma,
+				  unsigned long address)
+{
+	flush_tlb_range(vma, address, address + PAGE_SIZE);
+}
+
+static inline void flush_tlb_kernel_page(unsigned long address)
+{
+	flush_tlb_kernel_range(address, address + PAGE_SIZE);
+}
+
+extern void reload_tlb_page(struct vm_area_struct *vma, unsigned long addr,
+			    pte_t pte);
+
+#endif /* _ASM_NIOS2_TLBFLUSH_H */
diff --git a/arch/nios2/include/asm/traps.h b/arch/nios2/include/asm/traps.h
new file mode 100644
index 000000000..82a484732
--- /dev/null
+++ b/arch/nios2/include/asm/traps.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_TRAPS_H
+#define _ASM_NIOS2_TRAPS_H
+
+#define TRAP_ID_SYSCALL		0
+
+#ifndef __ASSEMBLY__
+void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr);
+#endif
+
+#endif /* _ASM_NIOS2_TRAPS_H */
diff --git a/arch/nios2/include/asm/uaccess.h b/arch/nios2/include/asm/uaccess.h
new file mode 100644
index 000000000..b8299082a
--- /dev/null
+++ b/arch/nios2/include/asm/uaccess.h
@@ -0,0 +1,189 @@
+/*
+ * User space memory access functions for Nios II
+ *
+ * Copyright (C) 2010-2011, Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009, Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_UACCESS_H
+#define _ASM_NIOS2_UACCESS_H
+
+#include <linux/string.h>
+
+#include <asm/page.h>
+
+#include <asm/extable.h>
+#include <asm-generic/access_ok.h>
+
+# define __EX_TABLE_SECTION	".section __ex_table,\"a\"\n"
+
+/*
+ * Zero Userspace
+ */
+
+static inline unsigned long __must_check __clear_user(void __user *to,
+						      unsigned long n)
+{
+	__asm__ __volatile__ (
+		"1:     stb     zero, 0(%1)\n"
+		"       addi    %0, %0, -1\n"
+		"       addi    %1, %1, 1\n"
+		"       bne     %0, zero, 1b\n"
+		"2:\n"
+		__EX_TABLE_SECTION
+		".word  1b, 2b\n"
+		".previous\n"
+		: "=r" (n), "=r" (to)
+		: "0" (n), "1" (to)
+	);
+
+	return n;
+}
+
+static inline unsigned long __must_check clear_user(void __user *to,
+						    unsigned long n)
+{
+	if (!access_ok(to, n))
+		return n;
+	return __clear_user(to, n);
+}
+
+extern unsigned long
+raw_copy_from_user(void *to, const void __user *from, unsigned long n);
+extern unsigned long
+raw_copy_to_user(void __user *to, const void *from, unsigned long n);
+#define INLINE_COPY_FROM_USER
+#define INLINE_COPY_TO_USER
+
+extern long strncpy_from_user(char *__to, const char __user *__from,
+			      long __len);
+extern __must_check long strnlen_user(const char __user *s, long n);
+
+/* Optimized macros */
+#define __get_user_asm(val, insn, addr, err)				\
+{									\
+	unsigned long __gu_val;						\
+	__asm__ __volatile__(						\
+	"       movi    %0, %3\n"					\
+	"1:   " insn " %1, 0(%2)\n"					\
+	"       movi     %0, 0\n"					\
+	"2:\n"								\
+	"       .section __ex_table,\"a\"\n"				\
+	"       .word 1b, 2b\n"						\
+	"       .previous"						\
+	: "=&r" (err), "=r" (__gu_val)					\
+	: "r" (addr), "i" (-EFAULT));					\
+	val = (__force __typeof__(*(addr)))__gu_val;			\
+}
+
+extern void __get_user_unknown(void);
+
+#define __get_user_8(val, ptr, err) do {				\
+	u64 __val = 0;							\
+	err = 0;							\
+	if (raw_copy_from_user(&(__val), ptr, sizeof(val))) {		\
+		err = -EFAULT;						\
+	} else {							\
+		val = (typeof(val))(typeof((val) - (val)))__val;	\
+	}								\
+	} while (0)
+
+#define __get_user_common(val, size, ptr, err)				\
+do {									\
+	switch (size) {							\
+	case 1:								\
+		__get_user_asm(val, "ldbu", ptr, err);			\
+		break;							\
+	case 2:								\
+		__get_user_asm(val, "ldhu", ptr, err);			\
+		break;							\
+	case 4:								\
+		__get_user_asm(val, "ldw", ptr, err);			\
+		break;							\
+	case 8:								\
+		__get_user_8(val, ptr, err);				\
+		break;							\
+	default:							\
+		__get_user_unknown();					\
+		break;							\
+	}								\
+} while (0)
+
+#define __get_user(x, ptr)						\
+	({								\
+	long __gu_err = -EFAULT;					\
+	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\
+	__get_user_common(x, sizeof(*(ptr)), __gu_ptr, __gu_err);	\
+	__gu_err;							\
+	})
+
+#define get_user(x, ptr)						\
+({									\
+	long __gu_err = -EFAULT;					\
+	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\
+	if (access_ok( __gu_ptr, sizeof(*__gu_ptr)))	\
+		__get_user_common(x, sizeof(*__gu_ptr),			\
+			__gu_ptr, __gu_err);				\
+	__gu_err;							\
+})
+
+#define __put_user_asm(val, insn, ptr, err)				\
+{									\
+	__asm__ __volatile__(						\
+	"       movi    %0, %3\n"					\
+	"1:   " insn " %1, 0(%2)\n"					\
+	"       movi     %0, 0\n"					\
+	"2:\n"								\
+	"       .section __ex_table,\"a\"\n"				\
+	"       .word 1b, 2b\n"						\
+	"       .previous\n"						\
+	: "=&r" (err)							\
+	: "r" (val), "r" (ptr), "i" (-EFAULT));				\
+}
+
+#define __put_user_common(__pu_val, __pu_ptr)				\
+({									\
+	long __pu_err = -EFAULT;					\
+	switch (sizeof(*__pu_ptr)) {					\
+	case 1:								\
+		__put_user_asm(__pu_val, "stb", __pu_ptr, __pu_err);	\
+		break;							\
+	case 2:								\
+		__put_user_asm(__pu_val, "sth", __pu_ptr, __pu_err);	\
+		break;							\
+	case 4:								\
+		__put_user_asm(__pu_val, "stw", __pu_ptr, __pu_err);	\
+		break;							\
+	default:							\
+		/* XXX: This looks wrong... */				\
+		__pu_err = 0;						\
+		if (__copy_to_user(__pu_ptr, &(__pu_val),		\
+			sizeof(*__pu_ptr)))				\
+			__pu_err = -EFAULT;				\
+		break;							\
+	}								\
+	__pu_err;							\
+})
+
+#define __put_user(x, ptr)						\
+({									\
+	__auto_type __pu_ptr = (ptr);					\
+	typeof(*__pu_ptr) __pu_val = (typeof(*__pu_ptr))(x);		\
+	__put_user_common(__pu_val, __pu_ptr);				\
+})
+
+#define put_user(x, ptr)						\
+({									\
+	__auto_type __pu_ptr = (ptr);					\
+	typeof(*__pu_ptr) __pu_val = (typeof(*__pu_ptr))(x);		\
+	access_ok(__pu_ptr, sizeof(*__pu_ptr)) ?			\
+		__put_user_common(__pu_val, __pu_ptr) :			\
+		-EFAULT;						\
+})
+
+#endif /* _ASM_NIOS2_UACCESS_H */
diff --git a/arch/nios2/include/asm/vmalloc.h b/arch/nios2/include/asm/vmalloc.h
new file mode 100644
index 000000000..ec7a92600
--- /dev/null
+++ b/arch/nios2/include/asm/vmalloc.h
@@ -0,0 +1,4 @@
+#ifndef _ASM_NIOS2_VMALLOC_H
+#define _ASM_NIOS2_VMALLOC_H
+
+#endif /* _ASM_NIOS2_VMALLOC_H */
diff --git a/arch/nios2/include/uapi/asm/Kbuild b/arch/nios2/include/uapi/asm/Kbuild
new file mode 100644
index 000000000..e78470141
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/Kbuild
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+generic-y += ucontext.h
diff --git a/arch/nios2/include/uapi/asm/byteorder.h b/arch/nios2/include/uapi/asm/byteorder.h
new file mode 100644
index 000000000..639007a55
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/byteorder.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2009   Thomas Chou <thomas@wytron.com.tw>
+ * Copyright (C) 2004   Microtronix Datacom Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef _ASM_NIOS2_BYTEORDER_H
+#define _ASM_NIOS2_BYTEORDER_H
+
+#include <linux/byteorder/little_endian.h>
+
+#endif
diff --git a/arch/nios2/include/uapi/asm/elf.h b/arch/nios2/include/uapi/asm/elf.h
new file mode 100644
index 000000000..ab0df71f8
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/elf.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+
+#ifndef _UAPI_ASM_NIOS2_ELF_H
+#define _UAPI_ASM_NIOS2_ELF_H
+
+#include <linux/ptrace.h>
+
+/* Relocation types */
+#define R_NIOS2_NONE		0
+#define R_NIOS2_S16		1
+#define R_NIOS2_U16		2
+#define R_NIOS2_PCREL16		3
+#define R_NIOS2_CALL26		4
+#define R_NIOS2_IMM5		5
+#define R_NIOS2_CACHE_OPX	6
+#define R_NIOS2_IMM6		7
+#define R_NIOS2_IMM8		8
+#define R_NIOS2_HI16		9
+#define R_NIOS2_LO16		10
+#define R_NIOS2_HIADJ16		11
+#define R_NIOS2_BFD_RELOC_32	12
+#define R_NIOS2_BFD_RELOC_16	13
+#define R_NIOS2_BFD_RELOC_8	14
+#define R_NIOS2_GPREL		15
+#define R_NIOS2_GNU_VTINHERIT	16
+#define R_NIOS2_GNU_VTENTRY	17
+#define R_NIOS2_UJMP		18
+#define R_NIOS2_CJMP		19
+#define R_NIOS2_CALLR		20
+#define R_NIOS2_ALIGN		21
+/* Keep this the last entry.  */
+#define R_NIOS2_NUM		22
+
+typedef unsigned long elf_greg_t;
+
+#define ELF_NGREG		49
+typedef elf_greg_t elf_gregset_t[ELF_NGREG];
+
+typedef unsigned long elf_fpregset_t;
+
+/*
+ * These are used to set parameters in the core dumps.
+ */
+#define ELF_CLASS	ELFCLASS32
+#define ELF_DATA	ELFDATA2LSB
+#define ELF_ARCH	EM_ALTERA_NIOS2
+
+#endif /* _UAPI_ASM_NIOS2_ELF_H */
diff --git a/arch/nios2/include/uapi/asm/ptrace.h b/arch/nios2/include/uapi/asm/ptrace.h
new file mode 100644
index 000000000..2b91dbe5b
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/ptrace.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * based on m68k asm/processor.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _UAPI_ASM_NIOS2_PTRACE_H
+#define _UAPI_ASM_NIOS2_PTRACE_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+
+/*
+ * Register numbers used by 'ptrace' system call interface.
+ */
+
+/* GP registers */
+#define PTR_R0		0
+#define PTR_R1		1
+#define PTR_R2		2
+#define PTR_R3		3
+#define PTR_R4		4
+#define PTR_R5		5
+#define PTR_R6		6
+#define PTR_R7		7
+#define PTR_R8		8
+#define PTR_R9		9
+#define PTR_R10		10
+#define PTR_R11		11
+#define PTR_R12		12
+#define PTR_R13		13
+#define PTR_R14		14
+#define PTR_R15		15
+#define PTR_R16		16
+#define PTR_R17		17
+#define PTR_R18		18
+#define PTR_R19		19
+#define PTR_R20		20
+#define PTR_R21		21
+#define PTR_R22		22
+#define PTR_R23		23
+#define PTR_R24		24
+#define PTR_R25		25
+#define PTR_GP		26
+#define PTR_SP		27
+#define PTR_FP		28
+#define PTR_EA		29
+#define PTR_BA		30
+#define PTR_RA		31
+/* Control registers */
+#define PTR_PC		32
+#define PTR_STATUS	33
+#define PTR_ESTATUS	34
+#define PTR_BSTATUS	35
+#define PTR_IENABLE	36
+#define PTR_IPENDING	37
+#define PTR_CPUID	38
+#define PTR_CTL6	39
+#define PTR_EXCEPTION	40
+#define PTR_PTEADDR	41
+#define PTR_TLBACC	42
+#define PTR_TLBMISC	43
+#define PTR_ECCINJ	44
+#define PTR_BADADDR	45
+#define PTR_CONFIG	46
+#define PTR_MPUBASE	47
+#define PTR_MPUACC	48
+
+#define NUM_PTRACE_REG (PTR_MPUACC + 1)
+
+/* User structures for general purpose registers.  */
+struct user_pt_regs {
+	__u32		regs[49];
+};
+
+#endif /* __ASSEMBLY__ */
+#endif /* _UAPI_ASM_NIOS2_PTRACE_H */
diff --git a/arch/nios2/include/uapi/asm/sigcontext.h b/arch/nios2/include/uapi/asm/sigcontext.h
new file mode 100644
index 000000000..204ae3475
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/sigcontext.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2004, Microtronix Datacom Ltd.
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ */
+
+#ifndef _UAPI__ASM_SIGCONTEXT_H
+#define _UAPI__ASM_SIGCONTEXT_H
+
+#include <linux/types.h>
+
+#define MCONTEXT_VERSION 2
+
+struct sigcontext {
+	int version;
+	unsigned long gregs[32];
+};
+
+#endif
diff --git a/arch/nios2/include/uapi/asm/signal.h b/arch/nios2/include/uapi/asm/signal.h
new file mode 100644
index 000000000..b0d983068
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/signal.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright Altera Corporation (C) 2013. All rights reserved
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#ifndef _ASM_NIOS2_SIGNAL_H
+#define _ASM_NIOS2_SIGNAL_H
+
+#define SA_RESTORER 0x04000000
+#include <asm-generic/signal.h>
+
+#endif /* _ASM_NIOS2_SIGNAL_H */
diff --git a/arch/nios2/include/uapi/asm/swab.h b/arch/nios2/include/uapi/asm/swab.h
new file mode 100644
index 000000000..9750547a5
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/swab.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2012 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2011 Pyramid Technical Consultants, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#ifndef _ASM_NIOS2_SWAB_H
+#define _ASM_NIOS2_SWAB_H
+
+#include <linux/types.h>
+#include <asm-generic/swab.h>
+
+#ifdef CONFIG_NIOS2_CI_SWAB_SUPPORT
+#ifdef __GNUC__
+
+#define __nios2_swab(x)		\
+	__builtin_custom_ini(CONFIG_NIOS2_CI_SWAB_NO, (x))
+
+static inline __attribute__((const)) __u16 __arch_swab16(__u16 x)
+{
+	return (__u16) __nios2_swab(((__u32) x) << 16);
+}
+#define __arch_swab16 __arch_swab16
+
+static inline __attribute__((const)) __u32 __arch_swab32(__u32 x)
+{
+	return (__u32) __nios2_swab(x);
+}
+#define __arch_swab32 __arch_swab32
+
+#endif /* __GNUC__ */
+#endif /* CONFIG_NIOS2_CI_SWAB_SUPPORT */
+
+#endif /* _ASM_NIOS2_SWAB_H */
diff --git a/arch/nios2/include/uapi/asm/unistd.h b/arch/nios2/include/uapi/asm/unistd.h
new file mode 100644
index 000000000..0b4bb1d41
--- /dev/null
+++ b/arch/nios2/include/uapi/asm/unistd.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2013 Altera Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+ #define sys_mmap2 sys_mmap_pgoff
+
+#define __ARCH_WANT_RENAMEAT
+#define __ARCH_WANT_STAT64
+#define __ARCH_WANT_SET_GET_RLIMIT
+#define __ARCH_WANT_TIME32_SYSCALLS
+
+/* Use the standard ABI for syscalls */
+#include <asm-generic/unistd.h>
+
+/* Additional Nios II specific syscalls. */
+#define __NR_cacheflush (__NR_arch_specific_syscall)
+__SYSCALL(__NR_cacheflush, sys_cacheflush)
diff --git a/arch/nios2/kernel/.gitignore b/arch/nios2/kernel/.gitignore
new file mode 100644
index 000000000..bbb90f92d
--- /dev/null
+++ b/arch/nios2/kernel/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vmlinux.lds
diff --git a/arch/nios2/kernel/Makefile b/arch/nios2/kernel/Makefile
new file mode 100644
index 000000000..78a913181
--- /dev/null
+++ b/arch/nios2/kernel/Makefile
@@ -0,0 +1,26 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the nios2 linux kernel.
+#
+
+extra-y	+= vmlinux.lds
+
+obj-y	+= head.o
+obj-y	+= cpuinfo.o
+obj-y	+= entry.o
+obj-y	+= insnemu.o
+obj-y	+= irq.o
+obj-y	+= nios2_ksyms.o
+obj-y	+= process.o
+obj-y	+= prom.o
+obj-y	+= ptrace.o
+obj-y	+= setup.o
+obj-y	+= signal.o
+obj-y	+= sys_nios2.o
+obj-y	+= syscall_table.o
+obj-y	+= time.o
+obj-y	+= traps.o
+
+obj-$(CONFIG_KGDB)			+= kgdb.o
+obj-$(CONFIG_MODULES)			+= module.o
+obj-$(CONFIG_NIOS2_ALIGNMENT_TRAP)	+= misaligned.o
diff --git a/arch/nios2/kernel/asm-offsets.c b/arch/nios2/kernel/asm-offsets.c
new file mode 100644
index 000000000..e3d9b7b6f
--- /dev/null
+++ b/arch/nios2/kernel/asm-offsets.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ */
+
+#include <linux/stddef.h>
+#include <linux/sched.h>
+#include <linux/kernel_stat.h>
+#include <linux/ptrace.h>
+#include <linux/hardirq.h>
+#include <linux/thread_info.h>
+#include <linux/kbuild.h>
+
+int main(void)
+{
+	/* struct task_struct */
+	OFFSET(TASK_THREAD, task_struct, thread);
+	BLANK();
+
+	/* struct thread_struct */
+	OFFSET(THREAD_KSP, thread_struct, ksp);
+	OFFSET(THREAD_KPSR, thread_struct, kpsr);
+	BLANK();
+
+	/* struct pt_regs */
+	OFFSET(PT_ORIG_R2, pt_regs, orig_r2);
+	OFFSET(PT_ORIG_R7, pt_regs, orig_r7);
+
+	OFFSET(PT_R1, pt_regs, r1);
+	OFFSET(PT_R2, pt_regs, r2);
+	OFFSET(PT_R3, pt_regs, r3);
+	OFFSET(PT_R4, pt_regs, r4);
+	OFFSET(PT_R5, pt_regs, r5);
+	OFFSET(PT_R6, pt_regs, r6);
+	OFFSET(PT_R7, pt_regs, r7);
+	OFFSET(PT_R8, pt_regs, r8);
+	OFFSET(PT_R9, pt_regs, r9);
+	OFFSET(PT_R10, pt_regs, r10);
+	OFFSET(PT_R11, pt_regs, r11);
+	OFFSET(PT_R12, pt_regs, r12);
+	OFFSET(PT_R13, pt_regs, r13);
+	OFFSET(PT_R14, pt_regs, r14);
+	OFFSET(PT_R15, pt_regs, r15);
+	OFFSET(PT_EA, pt_regs, ea);
+	OFFSET(PT_RA, pt_regs, ra);
+	OFFSET(PT_FP, pt_regs, fp);
+	OFFSET(PT_SP, pt_regs, sp);
+	OFFSET(PT_GP, pt_regs, gp);
+	OFFSET(PT_ESTATUS, pt_regs, estatus);
+	DEFINE(PT_REGS_SIZE, sizeof(struct pt_regs));
+	BLANK();
+
+	/* struct switch_stack */
+	OFFSET(SW_R16, switch_stack, r16);
+	OFFSET(SW_R17, switch_stack, r17);
+	OFFSET(SW_R18, switch_stack, r18);
+	OFFSET(SW_R19, switch_stack, r19);
+	OFFSET(SW_R20, switch_stack, r20);
+	OFFSET(SW_R21, switch_stack, r21);
+	OFFSET(SW_R22, switch_stack, r22);
+	OFFSET(SW_R23, switch_stack, r23);
+	OFFSET(SW_FP, switch_stack, fp);
+	OFFSET(SW_GP, switch_stack, gp);
+	OFFSET(SW_RA, switch_stack, ra);
+	DEFINE(SWITCH_STACK_SIZE, sizeof(struct switch_stack));
+	BLANK();
+
+	/* struct thread_info */
+	OFFSET(TI_FLAGS, thread_info, flags);
+	OFFSET(TI_PREEMPT_COUNT, thread_info, preempt_count);
+	BLANK();
+
+	return 0;
+}
diff --git a/arch/nios2/kernel/cpuinfo.c b/arch/nios2/kernel/cpuinfo.c
new file mode 100644
index 000000000..203870c4b
--- /dev/null
+++ b/arch/nios2/kernel/cpuinfo.c
@@ -0,0 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * Based on cpuinfo.c from microblaze
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <linux/of.h>
+#include <asm/cpuinfo.h>
+
+struct cpuinfo cpuinfo;
+
+#define err_cpu(x) \
+	pr_err("ERROR: Nios II " x " different for kernel and DTS\n")
+
+static inline u32 fcpu(struct device_node *cpu, const char *n)
+{
+	u32 val = 0;
+
+	of_property_read_u32(cpu, n, &val);
+
+	return val;
+}
+
+void __init setup_cpuinfo(void)
+{
+	struct device_node *cpu;
+	const char *str;
+	int len;
+
+	cpu = of_get_cpu_node(0, NULL);
+	if (!cpu)
+		panic("%s: No CPU found in devicetree!\n", __func__);
+
+	if (!of_property_read_bool(cpu, "altr,has-initda"))
+		panic("initda instruction is unimplemented. Please update your "
+			"hardware system to have more than 4-byte line data "
+			"cache\n");
+
+	cpuinfo.cpu_clock_freq = fcpu(cpu, "clock-frequency");
+
+	str = of_get_property(cpu, "altr,implementation", &len);
+	if (str)
+		strlcpy(cpuinfo.cpu_impl, str, sizeof(cpuinfo.cpu_impl));
+	else
+		strcpy(cpuinfo.cpu_impl, "<unknown>");
+
+	cpuinfo.has_div = of_property_read_bool(cpu, "altr,has-div");
+	cpuinfo.has_mul = of_property_read_bool(cpu, "altr,has-mul");
+	cpuinfo.has_mulx = of_property_read_bool(cpu, "altr,has-mulx");
+	cpuinfo.has_bmx = of_property_read_bool(cpu, "altr,has-bmx");
+	cpuinfo.has_cdx = of_property_read_bool(cpu, "altr,has-cdx");
+	cpuinfo.mmu = of_property_read_bool(cpu, "altr,has-mmu");
+
+	if (IS_ENABLED(CONFIG_NIOS2_HW_DIV_SUPPORT) && !cpuinfo.has_div)
+		err_cpu("DIV");
+
+	if (IS_ENABLED(CONFIG_NIOS2_HW_MUL_SUPPORT) && !cpuinfo.has_mul)
+		err_cpu("MUL");
+
+	if (IS_ENABLED(CONFIG_NIOS2_HW_MULX_SUPPORT) && !cpuinfo.has_mulx)
+		err_cpu("MULX");
+
+	if (IS_ENABLED(CONFIG_NIOS2_BMX_SUPPORT) && !cpuinfo.has_bmx)
+		err_cpu("BMX");
+
+	if (IS_ENABLED(CONFIG_NIOS2_CDX_SUPPORT) && !cpuinfo.has_cdx)
+		err_cpu("CDX");
+
+	cpuinfo.tlb_num_ways = fcpu(cpu, "altr,tlb-num-ways");
+	if (!cpuinfo.tlb_num_ways)
+		panic("altr,tlb-num-ways can't be 0. Please check your hardware "
+			"system\n");
+	cpuinfo.icache_line_size = fcpu(cpu, "icache-line-size");
+	cpuinfo.icache_size = fcpu(cpu, "icache-size");
+	if (CONFIG_NIOS2_ICACHE_SIZE != cpuinfo.icache_size)
+		pr_warn("Warning: icache size configuration mismatch "
+		"(0x%x vs 0x%x) of CONFIG_NIOS2_ICACHE_SIZE vs "
+		"device tree icache-size\n",
+		CONFIG_NIOS2_ICACHE_SIZE, cpuinfo.icache_size);
+
+	cpuinfo.dcache_line_size = fcpu(cpu, "dcache-line-size");
+	if (CONFIG_NIOS2_DCACHE_LINE_SIZE != cpuinfo.dcache_line_size)
+		pr_warn("Warning: dcache line size configuration mismatch "
+		"(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_LINE_SIZE vs "
+		"device tree dcache-line-size\n",
+		CONFIG_NIOS2_DCACHE_LINE_SIZE, cpuinfo.dcache_line_size);
+	cpuinfo.dcache_size = fcpu(cpu, "dcache-size");
+	if (CONFIG_NIOS2_DCACHE_SIZE != cpuinfo.dcache_size)
+		pr_warn("Warning: dcache size configuration mismatch "
+			"(0x%x vs 0x%x) of CONFIG_NIOS2_DCACHE_SIZE vs "
+			"device tree dcache-size\n",
+			CONFIG_NIOS2_DCACHE_SIZE, cpuinfo.dcache_size);
+
+	cpuinfo.tlb_pid_num_bits = fcpu(cpu, "altr,pid-num-bits");
+	cpuinfo.tlb_num_ways_log2 = ilog2(cpuinfo.tlb_num_ways);
+	cpuinfo.tlb_num_entries = fcpu(cpu, "altr,tlb-num-entries");
+	cpuinfo.tlb_num_lines = cpuinfo.tlb_num_entries / cpuinfo.tlb_num_ways;
+	cpuinfo.tlb_ptr_sz = fcpu(cpu, "altr,tlb-ptr-sz");
+
+	cpuinfo.reset_addr = fcpu(cpu, "altr,reset-addr");
+	cpuinfo.exception_addr = fcpu(cpu, "altr,exception-addr");
+	cpuinfo.fast_tlb_miss_exc_addr = fcpu(cpu, "altr,fast-tlb-miss-addr");
+
+	of_node_put(cpu);
+}
+
+#ifdef CONFIG_PROC_FS
+
+/*
+ * Get CPU information for use by the procfs.
+ */
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+	const u32 clockfreq = cpuinfo.cpu_clock_freq;
+
+	seq_printf(m,
+		   "CPU:\t\tNios II/%s\n"
+		   "REV:\t\t%i\n"
+		   "MMU:\t\t%s\n"
+		   "FPU:\t\tnone\n"
+		   "Clocking:\t%u.%02u MHz\n"
+		   "BogoMips:\t%lu.%02lu\n"
+		   "Calibration:\t%lu loops\n",
+		   cpuinfo.cpu_impl,
+		   CONFIG_NIOS2_ARCH_REVISION,
+		   cpuinfo.mmu ? "present" : "none",
+		   clockfreq / 1000000, (clockfreq / 100000) % 10,
+		   (loops_per_jiffy * HZ) / 500000,
+		   ((loops_per_jiffy * HZ) / 5000) % 100,
+		   (loops_per_jiffy * HZ));
+
+	seq_printf(m,
+		   "HW:\n"
+		   " MUL:\t\t%s\n"
+		   " MULX:\t\t%s\n"
+		   " DIV:\t\t%s\n"
+		   " BMX:\t\t%s\n"
+		   " CDX:\t\t%s\n",
+		   cpuinfo.has_mul ? "yes" : "no",
+		   cpuinfo.has_mulx ? "yes" : "no",
+		   cpuinfo.has_div ? "yes" : "no",
+		   cpuinfo.has_bmx ? "yes" : "no",
+		   cpuinfo.has_cdx ? "yes" : "no");
+
+	seq_printf(m,
+		   "Icache:\t\t%ukB, line length: %u\n",
+		   cpuinfo.icache_size >> 10,
+		   cpuinfo.icache_line_size);
+
+	seq_printf(m,
+		   "Dcache:\t\t%ukB, line length: %u\n",
+		   cpuinfo.dcache_size >> 10,
+		   cpuinfo.dcache_line_size);
+
+	seq_printf(m,
+		   "TLB:\t\t%u ways, %u entries, %u PID bits\n",
+		   cpuinfo.tlb_num_ways,
+		   cpuinfo.tlb_num_entries,
+		   cpuinfo.tlb_pid_num_bits);
+
+	return 0;
+}
+
+static void *cpuinfo_start(struct seq_file *m, loff_t *pos)
+{
+	unsigned long i = *pos;
+
+	return i < num_possible_cpus() ? (void *) (i + 1) : NULL;
+}
+
+static void *cpuinfo_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	++*pos;
+	return cpuinfo_start(m, pos);
+}
+
+static void cpuinfo_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+	.start	= cpuinfo_start,
+	.next	= cpuinfo_next,
+	.stop	= cpuinfo_stop,
+	.show	= show_cpuinfo
+};
+
+#endif /* CONFIG_PROC_FS */
diff --git a/arch/nios2/kernel/entry.S b/arch/nios2/kernel/entry.S
new file mode 100644
index 000000000..99f0a65e6
--- /dev/null
+++ b/arch/nios2/kernel/entry.S
@@ -0,0 +1,568 @@
+/*
+ * linux/arch/nios2/kernel/entry.S
+ *
+ * Copyright (C) 2013-2014  Altera Corporation
+ * Copyright (C) 2009, Wind River Systems Inc
+ *
+ * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ *  Copyright (C) 1999-2002, Greg Ungerer (gerg@snapgear.com)
+ *  Copyright (C) 1998  D. Jeff Dionne <jeff@lineo.ca>,
+ *                      Kenneth Albanowski <kjahds@kjahds.com>,
+ *  Copyright (C) 2000  Lineo Inc. (www.lineo.com)
+ *  Copyright (C) 2004  Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Linux/m68k support by Hamish Macdonald
+ *
+ * 68060 fixes by Jesper Skov
+ * ColdFire support by Greg Ungerer (gerg@snapgear.com)
+ * 5307 fixes by David W. Miller
+ * linux 2.4 support David McCullough <davidm@snapgear.com>
+ */
+
+#include <linux/sys.h>
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/asm-macros.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+#include <asm/setup.h>
+#include <asm/entry.h>
+#include <asm/unistd.h>
+#include <asm/processor.h>
+
+.macro GET_THREAD_INFO reg
+.if THREAD_SIZE & 0xffff0000
+	andhi	\reg, sp, %hi(~(THREAD_SIZE-1))
+.else
+	addi	\reg, r0, %lo(~(THREAD_SIZE-1))
+	and	\reg, \reg, sp
+.endif
+.endm
+
+.macro	kuser_cmpxchg_check
+	/*
+	 * Make sure our user space atomic helper is restarted if it was
+	 * interrupted in a critical region.
+	 * ea-4 = address of interrupted insn (ea must be preserved).
+	 * sp = saved regs.
+	 * cmpxchg_ldw = first critical insn, cmpxchg_stw = last critical insn.
+	 * If ea <= cmpxchg_stw and ea > cmpxchg_ldw then saved EA is set to
+	 * cmpxchg_ldw + 4.
+	*/
+	/* et = cmpxchg_stw + 4 */
+	movui   et, (KUSER_BASE + 4 + (cmpxchg_stw - __kuser_helper_start))
+	bgtu	ea, et, 1f
+
+	subi	et, et, (cmpxchg_stw - cmpxchg_ldw) /* et = cmpxchg_ldw + 4 */
+	bltu	ea, et, 1f
+	stw	et, PT_EA(sp)	/* fix up EA */
+	mov	ea, et
+1:
+.endm
+
+.section .rodata
+.align 4
+exception_table:
+	.word unhandled_exception	/* 0 - Reset */
+	.word unhandled_exception	/* 1 - Processor-only Reset */
+	.word external_interrupt	/* 2 - Interrupt */
+	.word handle_trap		/* 3 - Trap Instruction */
+
+	.word instruction_trap		/* 4 - Unimplemented instruction */
+	.word handle_illegal		/* 5 - Illegal instruction */
+	.word handle_unaligned		/* 6 - Misaligned data access */
+	.word handle_unaligned		/* 7 - Misaligned destination address */
+
+	.word handle_diverror		/* 8 - Division error */
+	.word protection_exception_ba	/* 9 - Supervisor-only instr. address */
+	.word protection_exception_instr /* 10 - Supervisor only instruction */
+	.word protection_exception_ba	/* 11 - Supervisor only data address */
+
+	.word unhandled_exception	/* 12 - Double TLB miss (data) */
+	.word protection_exception_pte	/* 13 - TLB permission violation (x) */
+	.word protection_exception_pte	/* 14 - TLB permission violation (r) */
+	.word protection_exception_pte	/* 15 - TLB permission violation (w) */
+
+	.word unhandled_exception	/* 16 - MPU region violation */
+
+trap_table:
+	.word	handle_system_call	/* 0  */
+	.word	handle_trap_1		/* 1  */
+	.word	handle_trap_2		/* 2  */
+	.word	handle_trap_3		/* 3  */
+	.word	handle_trap_reserved	/* 4  */
+	.word	handle_trap_reserved	/* 5  */
+	.word	handle_trap_reserved	/* 6  */
+	.word	handle_trap_reserved	/* 7  */
+	.word	handle_trap_reserved	/* 8  */
+	.word	handle_trap_reserved	/* 9  */
+	.word	handle_trap_reserved	/* 10 */
+	.word	handle_trap_reserved	/* 11 */
+	.word	handle_trap_reserved	/* 12 */
+	.word	handle_trap_reserved	/* 13 */
+	.word	handle_trap_reserved	/* 14 */
+	.word	handle_trap_reserved	/* 15 */
+	.word	handle_trap_reserved	/* 16 */
+	.word	handle_trap_reserved	/* 17 */
+	.word	handle_trap_reserved	/* 18 */
+	.word	handle_trap_reserved	/* 19 */
+	.word	handle_trap_reserved	/* 20 */
+	.word	handle_trap_reserved	/* 21 */
+	.word	handle_trap_reserved	/* 22 */
+	.word	handle_trap_reserved	/* 23 */
+	.word	handle_trap_reserved	/* 24 */
+	.word	handle_trap_reserved	/* 25 */
+	.word	handle_trap_reserved	/* 26 */
+	.word	handle_trap_reserved	/* 27 */
+	.word	handle_trap_reserved	/* 28 */
+	.word	handle_trap_reserved	/* 29 */
+#ifdef CONFIG_KGDB
+	.word	handle_kgdb_breakpoint	/* 30 KGDB breakpoint */
+#else
+	.word	instruction_trap		/* 30 */
+#endif
+	.word	handle_breakpoint	/* 31 */
+
+.text
+.set noat
+.set nobreak
+
+ENTRY(inthandler)
+	SAVE_ALL
+
+	kuser_cmpxchg_check
+
+	/* Clear EH bit before we get a new excpetion in the kernel
+	 * and after we have saved it to the exception frame. This is done
+	 * whether it's trap, tlb-miss or interrupt. If we don't do this
+	 * estatus is not updated the next exception.
+	 */
+	rdctl	r24, status
+	movi	r9, %lo(~STATUS_EH)
+	and	r24, r24, r9
+	wrctl	status, r24
+
+	/* Read cause and vector and branch to the associated handler */
+	mov	r4, sp
+	rdctl	r5, exception
+	movia	r9, exception_table
+	add	r24, r9, r5
+	ldw	r24, 0(r24)
+	jmp	r24
+
+
+/***********************************************************************
+ * Handle traps
+ ***********************************************************************
+ */
+ENTRY(handle_trap)
+	ldwio	r24, -4(ea)	/* instruction that caused the exception */
+	srli	r24, r24, 4
+	andi	r24, r24, 0x7c
+	movia	r9,trap_table
+	add	r24, r24, r9
+	ldw	r24, 0(r24)
+	jmp	r24
+
+
+/***********************************************************************
+ * Handle system calls
+ ***********************************************************************
+ */
+ENTRY(handle_system_call)
+	/* Enable interrupts */
+	rdctl	r10, status
+	ori	r10, r10, STATUS_PIE
+	wrctl	status, r10
+
+	/* Reload registers destroyed by common code. */
+	ldw	r4, PT_R4(sp)
+	ldw	r5, PT_R5(sp)
+
+local_restart:
+	stw	r2, PT_ORIG_R2(sp)
+	/* Check that the requested system call is within limits */
+	movui	r1, __NR_syscalls
+	bgeu	r2, r1, ret_invsyscall
+	slli	r1, r2, 2
+	movhi	r11, %hiadj(sys_call_table)
+	add	r1, r1, r11
+	ldw	r1, %lo(sys_call_table)(r1)
+
+	/* Check if we are being traced */
+	GET_THREAD_INFO r11
+	ldw	r11,TI_FLAGS(r11)
+	BTBNZ   r11,r11,TIF_SYSCALL_TRACE,traced_system_call
+
+	/* Execute the system call */
+	callr	r1
+
+	/* If the syscall returns a negative result:
+	 *   Set r7 to 1 to indicate error,
+	 *   Negate r2 to get a positive error code
+	 * If the syscall returns zero or a positive value:
+	 *   Set r7 to 0.
+	 * The sigreturn system calls will skip the code below by
+	 * adding to register ra. To avoid destroying registers
+	 */
+translate_rc_and_ret:
+	movi	r1, 0
+	bge	r2, zero, 3f
+	ldw	r1, PT_ORIG_R2(sp)
+	addi	r1, r1, 1
+	beq	r1, zero, 3f
+	sub	r2, zero, r2
+	movi	r1, 1
+3:
+	stw	r2, PT_R2(sp)
+	stw	r1, PT_R7(sp)
+end_translate_rc_and_ret:
+
+ret_from_exception:
+	ldw	r1, PT_ESTATUS(sp)
+	/* if so, skip resched, signals */
+	TSTBNZ	r1, r1, ESTATUS_EU, Luser_return
+
+restore_all:
+	rdctl	r10, status			/* disable intrs */
+	andi	r10, r10, %lo(~STATUS_PIE)
+	wrctl	status, r10
+	RESTORE_ALL
+	eret
+
+	/* If the syscall number was invalid return ENOSYS */
+ret_invsyscall:
+	movi	r2, -ENOSYS
+	br	translate_rc_and_ret
+
+	/* This implements the same as above, except it calls
+	 * do_syscall_trace_enter and do_syscall_trace_exit before and after the
+	 * syscall in order for utilities like strace and gdb to work.
+	 */
+traced_system_call:
+	SAVE_SWITCH_STACK
+	call	do_syscall_trace_enter
+	RESTORE_SWITCH_STACK
+
+	/* Create system call register arguments. The 5th and 6th
+	   arguments on stack are already in place at the beginning
+	   of pt_regs. */
+	ldw	r2, PT_R2(sp)
+	ldw	r4, PT_R4(sp)
+	ldw	r5, PT_R5(sp)
+	ldw	r6, PT_R6(sp)
+	ldw	r7, PT_R7(sp)
+
+	/* Fetch the syscall function. */
+	movui	r1, __NR_syscalls
+	bgeu	r2, r1, traced_invsyscall
+	slli	r1, r2, 2
+	movhi	r11,%hiadj(sys_call_table)
+	add	r1, r1, r11
+	ldw	r1, %lo(sys_call_table)(r1)
+
+	callr	r1
+
+	/* If the syscall returns a negative result:
+	 *   Set r7 to 1 to indicate error,
+	 *   Negate r2 to get a positive error code
+	 * If the syscall returns zero or a positive value:
+	 *   Set r7 to 0.
+	 * The sigreturn system calls will skip the code below by
+	 * adding to register ra. To avoid destroying registers
+	 */
+translate_rc_and_ret2:
+	movi	r1, 0
+	bge	r2, zero, 4f
+	ldw	r1, PT_ORIG_R2(sp)
+	addi	r1, r1, 1
+	beq	r1, zero, 4f
+	sub	r2, zero, r2
+	movi	r1, 1
+4:
+	stw	r2, PT_R2(sp)
+	stw	r1, PT_R7(sp)
+end_translate_rc_and_ret2:
+	SAVE_SWITCH_STACK
+	call	do_syscall_trace_exit
+	RESTORE_SWITCH_STACK
+	br	ret_from_exception
+
+	/* If the syscall number was invalid return ENOSYS */
+traced_invsyscall:
+	movi	r2, -ENOSYS
+	br	translate_rc_and_ret2
+
+Luser_return:
+	GET_THREAD_INFO	r11			/* get thread_info pointer */
+	ldw	r10, TI_FLAGS(r11)		/* get thread_info->flags */
+	ANDI32	r11, r10, _TIF_WORK_MASK
+	beq	r11, r0, restore_all		/* Nothing to do */
+	BTBZ	r1, r10, TIF_NEED_RESCHED, Lsignal_return
+
+	/* Reschedule work */
+	call	schedule
+	br	ret_from_exception
+
+Lsignal_return:
+	ANDI32	r1, r10, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME
+	beq	r1, r0, restore_all
+	mov	r4, sp			/* pt_regs */
+	SAVE_SWITCH_STACK
+	call	do_notify_resume
+	beq	r2, r0, no_work_pending
+	RESTORE_SWITCH_STACK
+	/* prepare restart syscall here without leaving kernel */
+	ldw	r2, PT_R2(sp)	/* reload syscall number in r2 */
+	ldw 	r4, PT_R4(sp)	/* reload syscall arguments r4-r9 */
+	ldw 	r5, PT_R5(sp)
+	ldw 	r6, PT_R6(sp)
+	ldw 	r7, PT_R7(sp)
+	ldw 	r8, PT_R8(sp)
+	ldw 	r9, PT_R9(sp)
+	br	local_restart	/* restart syscall */
+
+no_work_pending:
+	RESTORE_SWITCH_STACK
+	br	ret_from_exception
+
+/***********************************************************************
+ * Handle external interrupts.
+ ***********************************************************************
+ */
+/*
+ * This is the generic interrupt handler (for all hardware interrupt
+ * sources). It figures out the vector number and calls the appropriate
+ * interrupt service routine directly.
+ */
+external_interrupt:
+	rdctl	r12, ipending
+	rdctl	r9, ienable
+	and	r12, r12, r9
+	/* skip if no interrupt is pending */
+	beq	r12, r0, ret_from_interrupt
+
+	/*
+	 * Process an external hardware interrupt.
+	 */
+
+	addi	ea, ea, -4	/* re-issue the interrupted instruction */
+	stw	ea, PT_EA(sp)
+2:	movi	r4, %lo(-1)	/* Start from bit position 0,
+					highest priority */
+				/* This is the IRQ # for handler call */
+1:	andi	r10, r12, 1	/* Isolate bit we are interested in */
+	srli	r12, r12, 1	/* shift count is costly without hardware
+					multiplier */
+	addi	r4, r4, 1
+	beq	r10, r0, 1b
+	mov	r5, sp		/* Setup pt_regs pointer for handler call */
+	call	do_IRQ
+	rdctl	r12, ipending	/* check again if irq still pending */
+	rdctl	r9, ienable	/* Isolate possible interrupts */
+	and	r12, r12, r9
+	bne	r12, r0, 2b
+	/* br	ret_from_interrupt */ /* fall through to ret_from_interrupt */
+
+ENTRY(ret_from_interrupt)
+	ldw	r1, PT_ESTATUS(sp)	/* check if returning to kernel */
+	TSTBNZ	r1, r1, ESTATUS_EU, Luser_return
+
+#ifdef CONFIG_PREEMPTION
+	GET_THREAD_INFO	r1
+	ldw	r4, TI_PREEMPT_COUNT(r1)
+	bne	r4, r0, restore_all
+	ldw	r4, TI_FLAGS(r1)		/* ? Need resched set */
+	BTBZ	r10, r4, TIF_NEED_RESCHED, restore_all
+	ldw	r4, PT_ESTATUS(sp)	/* ? Interrupts off */
+	andi	r10, r4, ESTATUS_EPIE
+	beq	r10, r0, restore_all
+	call	preempt_schedule_irq
+#endif
+	br	restore_all
+
+/***********************************************************************
+ * A few syscall wrappers
+ ***********************************************************************
+ */
+/*
+ * int clone(unsigned long clone_flags, unsigned long newsp,
+ *		int __user * parent_tidptr, int __user * child_tidptr,
+ *		int tls_val)
+ */
+ENTRY(sys_clone)
+	SAVE_SWITCH_STACK
+	subi    sp, sp, 4 /* make space for tls pointer */
+	stw     r8, 0(sp) /* pass tls pointer (r8) via stack (5th argument) */
+	call	nios2_clone
+	addi    sp, sp, 4
+	RESTORE_SWITCH_STACK
+	ret
+
+ENTRY(sys_rt_sigreturn)
+	SAVE_SWITCH_STACK
+	mov	r4, sp
+	call	do_rt_sigreturn
+	RESTORE_SWITCH_STACK
+	addi	ra, ra, (end_translate_rc_and_ret - translate_rc_and_ret)
+	ret
+
+/***********************************************************************
+ * A few other wrappers and stubs
+ ***********************************************************************
+ */
+protection_exception_pte:
+	rdctl	r6, pteaddr
+	slli	r6, r6, 10
+	call	do_page_fault
+	br	ret_from_exception
+
+protection_exception_ba:
+	rdctl	r6, badaddr
+	call	do_page_fault
+	br	ret_from_exception
+
+protection_exception_instr:
+	call	handle_supervisor_instr
+	br	ret_from_exception
+
+handle_breakpoint:
+	call	breakpoint_c
+	br	ret_from_exception
+
+#ifdef CONFIG_NIOS2_ALIGNMENT_TRAP
+handle_unaligned:
+	SAVE_SWITCH_STACK
+	call	handle_unaligned_c
+	RESTORE_SWITCH_STACK
+	br	ret_from_exception
+#else
+handle_unaligned:
+	call	handle_unaligned_c
+	br	ret_from_exception
+#endif
+
+handle_illegal:
+	call	handle_illegal_c
+	br	ret_from_exception
+
+handle_diverror:
+	call	handle_diverror_c
+	br	ret_from_exception
+
+#ifdef CONFIG_KGDB
+handle_kgdb_breakpoint:
+	call	kgdb_breakpoint_c
+	br	ret_from_exception
+#endif
+
+handle_trap_1:
+	call	handle_trap_1_c
+	br	ret_from_exception
+
+handle_trap_2:
+	call	handle_trap_2_c
+	br	ret_from_exception
+
+handle_trap_3:
+handle_trap_reserved:
+	call	handle_trap_3_c
+	br	ret_from_exception
+
+/*
+ * Beware - when entering resume, prev (the current task) is
+ * in r4, next (the new task) is in r5, don't change these
+ * registers.
+ */
+ENTRY(resume)
+
+	rdctl	r7, status			/* save thread status reg */
+	stw	r7, TASK_THREAD + THREAD_KPSR(r4)
+
+	andi	r7, r7, %lo(~STATUS_PIE)	/* disable interrupts */
+	wrctl	status, r7
+
+	SAVE_SWITCH_STACK
+	stw	sp, TASK_THREAD + THREAD_KSP(r4)/* save kernel stack pointer */
+	ldw	sp, TASK_THREAD + THREAD_KSP(r5)/* restore new thread stack */
+	movia	r24, _current_thread		/* save thread */
+	GET_THREAD_INFO r1
+	stw	r1, 0(r24)
+	RESTORE_SWITCH_STACK
+
+	ldw	r7, TASK_THREAD + THREAD_KPSR(r5)/* restore thread status reg */
+	wrctl	status, r7
+	ret
+
+ENTRY(ret_from_fork)
+	call	schedule_tail
+	br	ret_from_exception
+
+ENTRY(ret_from_kernel_thread)
+	call	schedule_tail
+	mov	r4,r17	/* arg */
+	callr	r16	/* function */
+	br	ret_from_exception
+
+/*
+ * Kernel user helpers.
+ *
+ * Each segment is 64-byte aligned and will be mapped to the <User space>.
+ * New segments (if ever needed) must be added after the existing ones.
+ * This mechanism should be used only for things that are really small and
+ * justified, and not be abused freely.
+ *
+ */
+
+ /* Filling pads with undefined instructions. */
+.macro	kuser_pad sym size
+	.if	((. - \sym) & 3)
+	.rept	(4 - (. - \sym) & 3)
+	.byte	0
+	.endr
+	.endif
+	.rept	((\size - (. - \sym)) / 4)
+	.word	0xdeadbeef
+	.endr
+.endm
+
+	.align	6
+	.globl	__kuser_helper_start
+__kuser_helper_start:
+
+__kuser_helper_version:				/* @ 0x1000 */
+	.word	((__kuser_helper_end - __kuser_helper_start) >> 6)
+
+__kuser_cmpxchg:				/* @ 0x1004 */
+	/*
+	 * r4 pointer to exchange variable
+	 * r5 old value
+	 * r6 new value
+	 */
+cmpxchg_ldw:
+	ldw	r2, 0(r4)			/* load current value */
+	sub	r2, r2, r5			/* compare with old value */
+	bne	r2, zero, cmpxchg_ret
+
+	/* We had a match, store the new value */
+cmpxchg_stw:
+	stw	r6, 0(r4)
+cmpxchg_ret:
+	ret
+
+	kuser_pad __kuser_cmpxchg, 64
+
+	.globl	__kuser_sigtramp
+__kuser_sigtramp:
+	movi	r2, __NR_rt_sigreturn
+	trap
+
+	kuser_pad __kuser_sigtramp, 64
+
+	.globl	__kuser_helper_end
+__kuser_helper_end:
diff --git a/arch/nios2/kernel/head.S b/arch/nios2/kernel/head.S
new file mode 100644
index 000000000..372ce4a33
--- /dev/null
+++ b/arch/nios2/kernel/head.S
@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ * Copyright (C) 2001 Vic Phillips, Microtronix Datacom Ltd.
+ *
+ * Based on head.S for Altera's Excalibur development board with nios processor
+ *
+ * Based on the following from the Excalibur sdk distribution:
+ *	NA_MemoryMap.s, NR_JumpToStart.s, NR_Setup.s, NR_CWPManager.s
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <asm/thread_info.h>
+#include <asm/processor.h>
+#include <asm/cache.h>
+#include <asm/page.h>
+#include <asm/asm-offsets.h>
+#include <asm/asm-macros.h>
+
+/*
+ * ZERO_PAGE is a special page that is used for zero-initialized
+ * data and COW.
+ */
+.data
+.global empty_zero_page
+.align 12
+empty_zero_page:
+	.space	PAGE_SIZE
+
+/*
+ * This global variable is used as an extension to the nios'
+ * STATUS register to emulate a user/supervisor mode.
+ */
+	.data
+	.align	2
+	.set noat
+
+	.global _current_thread
+_current_thread:
+	.long	0
+/*
+ * Input(s): passed from u-boot
+ *   r4 - Optional pointer to a board information structure.
+ *   r5 - Optional pointer to the physical starting address of the init RAM
+ *        disk.
+ *   r6 - Optional pointer to the physical ending address of the init RAM
+ *        disk.
+ *   r7 - Optional pointer to the physical starting address of any kernel
+ *        command-line parameters.
+ */
+
+/*
+ * First executable code - detected and jumped to by the ROM bootstrap
+ * if the code resides in flash (looks for "Nios" at offset 0x0c from
+ * the potential executable image).
+ */
+	__HEAD
+ENTRY(_start)
+	wrctl	status, r0		/* Disable interrupts */
+
+	/* Initialize all cache lines within the instruction cache */
+	movia	r1, NIOS2_ICACHE_SIZE
+	movui	r2, NIOS2_ICACHE_LINE_SIZE
+
+icache_init:
+	initi	r1
+	sub	r1, r1, r2
+	bgt	r1, r0, icache_init
+	br	1f
+
+	/*
+	 * This is the default location for the exception handler. Code in jump
+	 * to our handler
+	 */
+ENTRY(exception_handler_hook)
+	movia	r24, inthandler
+	jmp	r24
+
+ENTRY(fast_handler)
+	nextpc et
+helper:
+	stw	r3, r3save - helper(et)
+
+	rdctl	r3 , pteaddr
+	srli	r3, r3, 12
+	slli	r3, r3, 2
+	movia	et, pgd_current
+
+	ldw	et, 0(et)
+	add	r3, et, r3
+	ldw	et, 0(r3)
+
+	rdctl	r3, pteaddr
+	andi	r3, r3, 0xfff
+	add	et, r3, et
+	ldw	et, 0(et)
+	wrctl	tlbacc, et
+	nextpc	et
+helper2:
+	ldw	r3, r3save - helper2(et)
+	subi	ea, ea, 4
+	eret
+r3save:
+	.word 0x0
+ENTRY(fast_handler_end)
+
+1:
+	/*
+	 * After the instruction cache is initialized, the data cache must
+	 * also be initialized.
+	 */
+	movia	r1, NIOS2_DCACHE_SIZE
+	movui	r2, NIOS2_DCACHE_LINE_SIZE
+
+dcache_init:
+	initd	0(r1)
+	sub	r1, r1, r2
+	bgt	r1, r0, dcache_init
+
+	nextpc	r1			/* Find out where we are */
+chkadr:
+	movia	r2, chkadr
+	beq	r1, r2,finish_move	/* We are running in RAM done */
+	addi	r1, r1,(_start - chkadr)	/* Source */
+	movia	r2, _start		/* Destination */
+	movia	r3, __bss_start		/* End of copy */
+
+loop_move:				/* r1: src, r2: dest, r3: last dest */
+	ldw	r8, 0(r1)		/* load a word from [r1] */
+	stw	r8, 0(r2)		/* store a word to dest [r2] */
+	flushd	0(r2)			/* Flush cache for safety */
+	addi 	r1, r1, 4		/* inc the src addr */
+	addi	r2, r2, 4		/* inc the dest addr */
+	blt	r2, r3, loop_move
+
+	movia	r1, finish_move		/* VMA(_start)->l1 */
+	jmp	r1			/* jmp to _start */
+
+finish_move:
+
+	/* Mask off all possible interrupts */
+	wrctl	ienable, r0
+
+	/* Clear .bss */
+	movia	r2, __bss_start
+	movia	r1, __bss_stop
+1:
+	stb	r0, 0(r2)
+	addi	r2, r2, 1
+	bne	r1, r2, 1b
+
+	movia	r1, init_thread_union	/* set stack at top of the task union */
+	addi	sp, r1, THREAD_SIZE
+	movia	r2, _current_thread	/* Remember current thread */
+	stw	r1, 0(r2)
+
+	movia	r1, nios2_boot_init	/* save args r4-r7 passed from u-boot */
+	callr	r1
+
+	movia	r1, start_kernel	/* call start_kernel as a subroutine */
+	callr	r1
+
+	/* If we return from start_kernel, break to the oci debugger and
+	 * buggered we are.
+	 */
+	break
+
+	/* End of startup code */
+.set at
diff --git a/arch/nios2/kernel/insnemu.S b/arch/nios2/kernel/insnemu.S
new file mode 100644
index 000000000..a027cc68b
--- /dev/null
+++ b/arch/nios2/kernel/insnemu.S
@@ -0,0 +1,580 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  Copyright (C) 2003-2013 Altera Corporation
+ *  All rights reserved.
+ */
+
+
+#include <linux/linkage.h>
+#include <asm/entry.h>
+
+.set noat
+.set nobreak
+
+/*
+* Explicitly allow the use of r1 (the assembler temporary register)
+* within this code. This register is normally reserved for the use of
+* the compiler.
+*/
+
+ENTRY(instruction_trap)
+	ldw	r1, PT_R1(sp)		// Restore registers
+	ldw	r2, PT_R2(sp)
+	ldw	r3, PT_R3(sp)
+	ldw	r4, PT_R4(sp)
+	ldw	r5, PT_R5(sp)
+	ldw	r6, PT_R6(sp)
+	ldw	r7, PT_R7(sp)
+	ldw	r8, PT_R8(sp)
+	ldw	r9, PT_R9(sp)
+	ldw	r10, PT_R10(sp)
+	ldw	r11, PT_R11(sp)
+	ldw	r12, PT_R12(sp)
+	ldw	r13, PT_R13(sp)
+	ldw	r14, PT_R14(sp)
+	ldw	r15, PT_R15(sp)
+	ldw	ra, PT_RA(sp)
+	ldw	fp, PT_FP(sp)
+	ldw	gp, PT_GP(sp)
+	ldw	et, PT_ESTATUS(sp)
+	wrctl	estatus, et
+	ldw	ea, PT_EA(sp)
+	ldw	et, PT_SP(sp)		/* backup sp in et */
+
+	addi	sp, sp, PT_REGS_SIZE
+
+	/* INSTRUCTION EMULATION
+	*  ---------------------
+	*
+	* Nios II processors generate exceptions for unimplemented instructions.
+	* The routines below emulate these instructions.  Depending on the
+	* processor core, the only instructions that might need to be emulated
+	* are div, divu, mul, muli, mulxss, mulxsu, and mulxuu.
+	*
+	* The emulations match the instructions, except for the following
+	* limitations:
+	*
+	* 1) The emulation routines do not emulate the use of the exception
+	*    temporary register (et) as a source operand because the exception
+	*    handler already has modified it.
+	*
+	* 2) The routines do not emulate the use of the stack pointer (sp) or
+	*    the exception return address register (ea) as a destination because
+	*    modifying these registers crashes the exception handler or the
+	*    interrupted routine.
+	*
+	* Detailed Design
+	* ---------------
+	*
+	* The emulation routines expect the contents of integer registers r0-r31
+	* to be on the stack at addresses sp, 4(sp), 8(sp), ... 124(sp).  The
+	* routines retrieve source operands from the stack and modify the
+	* destination register's value on the stack prior to the end of the
+	* exception handler.  Then all registers except the destination register
+	* are restored to their previous values.
+	*
+	* The instruction that causes the exception is found at address -4(ea).
+	* The instruction's OP and OPX fields identify the operation to be
+	* performed.
+	*
+	* One instruction, muli, is an I-type instruction that is identified by
+	* an OP field of 0x24.
+	*
+	* muli   AAAAA,BBBBB,IIIIIIIIIIIIIIII,-0x24-
+	*           27    22                6      0    <-- LSB of field
+	*
+	* The remaining emulated instructions are R-type and have an OP field
+	* of 0x3a.  Their OPX fields identify them.
+	*
+	* R-type AAAAA,BBBBB,CCCCC,XXXXXX,NNNNN,-0x3a-
+	*           27    22    17     11     6      0  <-- LSB of field
+	*
+	*
+	* Opcode Encoding.  muli is identified by its OP value.  Then OPX & 0x02
+	* is used to differentiate between the division opcodes and the
+	* remaining multiplication opcodes.
+	*
+	* Instruction   OP      OPX    OPX & 0x02
+	* -----------   ----    ----   ----------
+	* muli          0x24
+	* divu          0x3a    0x24         0
+	* div           0x3a    0x25         0
+	* mul           0x3a    0x27      != 0
+	* mulxuu        0x3a    0x07      != 0
+	* mulxsu        0x3a    0x17      != 0
+	* mulxss        0x3a    0x1f      != 0
+	*/
+
+
+	/*
+	* Save everything on the stack to make it easy for the emulation
+	* routines to retrieve the source register operands.
+	*/
+
+	addi sp, sp, -128
+	stw zero, 0(sp)	/* Save zero on stack to avoid special case for r0. */
+	stw r1, 4(sp)
+	stw r2,  8(sp)
+	stw r3, 12(sp)
+	stw r4, 16(sp)
+	stw r5, 20(sp)
+	stw r6, 24(sp)
+	stw r7, 28(sp)
+	stw r8, 32(sp)
+	stw r9, 36(sp)
+	stw r10, 40(sp)
+	stw r11, 44(sp)
+	stw r12, 48(sp)
+	stw r13, 52(sp)
+	stw r14, 56(sp)
+	stw r15, 60(sp)
+	stw r16, 64(sp)
+	stw r17, 68(sp)
+	stw r18, 72(sp)
+	stw r19, 76(sp)
+	stw r20, 80(sp)
+	stw r21, 84(sp)
+	stw r22, 88(sp)
+	stw r23, 92(sp)
+		/* Don't bother to save et.  It's already been changed. */
+	rdctl r5, estatus
+	stw r5,  100(sp)
+
+	stw gp, 104(sp)
+	stw et, 108(sp)	/* et contains previous sp value. */
+	stw fp, 112(sp)
+	stw ea, 116(sp)
+	stw ra, 120(sp)
+
+
+	/*
+	* Split the instruction into its fields.  We need 4*A, 4*B, and 4*C as
+	* offsets to the stack pointer for access to the stored register values.
+	*/
+	ldw r2,-4(ea)	/* r2 = AAAAA,BBBBB,IIIIIIIIIIIIIIII,PPPPPP */
+	roli r3, r2, 7	/* r3 = BBB,IIIIIIIIIIIIIIII,PPPPPP,AAAAA,BB */
+	roli r4, r3, 3	/* r4 = IIIIIIIIIIIIIIII,PPPPPP,AAAAA,BBBBB */
+	roli r5, r4, 2	/* r5 = IIIIIIIIIIIIII,PPPPPP,AAAAA,BBBBB,II */
+	srai r4, r4, 16	/* r4 = (sign-extended) IMM16 */
+	roli r6, r5, 5	/* r6 = XXXX,NNNNN,PPPPPP,AAAAA,BBBBB,CCCCC,XX */
+	andi r2, r2, 0x3f	/* r2 = 00000000000000000000000000,PPPPPP */
+	andi r3, r3, 0x7c	/* r3 = 0000000000000000000000000,AAAAA,00 */
+	andi r5, r5, 0x7c	/* r5 = 0000000000000000000000000,BBBBB,00 */
+	andi r6, r6, 0x7c	/* r6 = 0000000000000000000000000,CCCCC,00 */
+
+	/* Now
+	* r2 = OP
+	* r3 = 4*A
+	* r4 = IMM16 (sign extended)
+	* r5 = 4*B
+	* r6 = 4*C
+	*/
+
+	/*
+	* Get the operands.
+	*
+	* It is necessary to check for muli because it uses an I-type
+	* instruction format, while the other instructions are have an R-type
+	* format.
+	*
+	*  Prepare for either multiplication or division loop.
+	*  They both loop 32 times.
+	*/
+	movi r14, 32
+
+	add  r3, r3, sp		/* r3 = address of A-operand. */
+	ldw  r3, 0(r3)		/* r3 = A-operand. */
+	movi r7, 0x24		/* muli opcode (I-type instruction format) */
+	beq r2, r7, mul_immed /* muli doesn't use the B register as a source */
+
+	add  r5, r5, sp		/* r5 = address of B-operand. */
+	ldw  r5, 0(r5)		/* r5 = B-operand. */
+				/* r4 = SSSSSSSSSSSSSSSS,-----IMM16------ */
+				/* IMM16 not needed, align OPX portion */
+				/* r4 = SSSSSSSSSSSSSSSS,CCCCC,-OPX--,00000 */
+	srli r4, r4, 5		/* r4 = 00000,SSSSSSSSSSSSSSSS,CCCCC,-OPX-- */
+	andi r4, r4, 0x3f	/* r4 = 00000000000000000000000000,-OPX-- */
+
+	/* Now
+	* r2 = OP
+	* r3 = src1
+	* r5 = src2
+	* r4 = OPX (no longer can be muli)
+	* r6 = 4*C
+	*/
+
+
+	/*
+	*  Multiply or Divide?
+	*/
+	andi r7, r4, 0x02	/* For R-type multiply instructions,
+				   OPX & 0x02 != 0 */
+	bne r7, zero, multiply
+
+
+	/* DIVISION
+	*
+	* Divide an unsigned dividend by an unsigned divisor using
+	* a shift-and-subtract algorithm.  The example below shows
+	* 43 div 7 = 6 for 8-bit integers.  This classic algorithm uses a
+	* single register to store both the dividend and the quotient,
+	* allowing both values to be shifted with a single instruction.
+	*
+	*                               remainder dividend:quotient
+	*                               --------- -----------------
+	*   initialize                   00000000     00101011:
+	*   shift                        00000000     0101011:_
+	*   remainder >= divisor? no     00000000     0101011:0
+	*   shift                        00000000     101011:0_
+	*   remainder >= divisor? no     00000000     101011:00
+	*   shift                        00000001     01011:00_
+	*   remainder >= divisor? no     00000001     01011:000
+	*   shift                        00000010     1011:000_
+	*   remainder >= divisor? no     00000010     1011:0000
+	*   shift                        00000101     011:0000_
+	*   remainder >= divisor? no     00000101     011:00000
+	*   shift                        00001010     11:00000_
+	*   remainder >= divisor? yes    00001010     11:000001
+	*       remainder -= divisor   - 00000111
+	*                              ----------
+	*                                00000011     11:000001
+	*   shift                        00000111     1:000001_
+	*   remainder >= divisor? yes    00000111     1:0000011
+	*       remainder -= divisor   - 00000111
+	*                              ----------
+	*                                00000000     1:0000011
+	*   shift                        00000001     :0000011_
+	*   remainder >= divisor? no     00000001     :00000110
+	*
+	* The quotient is 00000110.
+	*/
+
+divide:
+	/*
+	*  Prepare for division by assuming the result
+	*  is unsigned, and storing its "sign" as 0.
+	*/
+	movi r17, 0
+
+
+	/* Which division opcode? */
+	xori r7, r4, 0x25		/* OPX of div */
+	bne r7, zero, unsigned_division
+
+
+	/*
+	*  OPX is div.  Determine and store the sign of the quotient.
+	*  Then take the absolute value of both operands.
+	*/
+	xor r17, r3, r5		/* MSB contains sign of quotient */
+	bge r3,zero,dividend_is_nonnegative
+	sub r3, zero, r3	/* -r3 */
+dividend_is_nonnegative:
+	bge r5, zero, divisor_is_nonnegative
+	sub r5, zero, r5	/* -r5 */
+divisor_is_nonnegative:
+
+
+unsigned_division:
+	/* Initialize the unsigned-division loop. */
+	movi r13, 0	/* remainder = 0 */
+
+	/* Now
+	* r3 = dividend : quotient
+	* r4 = 0x25 for div, 0x24 for divu
+	* r5 = divisor
+	* r13 = remainder
+	* r14 = loop counter (already initialized to 32)
+	* r17 = MSB contains sign of quotient
+	*/
+
+
+	/*
+	*   for (count = 32; count > 0; --count)
+	*   {
+	*/
+divide_loop:
+
+	/*
+	*       Division:
+	*
+	*       (remainder:dividend:quotient) <<= 1;
+	*/
+	slli r13, r13, 1
+	cmplt r7, r3, zero	/* r7 = MSB of r3 */
+	or r13, r13, r7
+	slli r3, r3, 1
+
+
+	/*
+	*       if (remainder >= divisor)
+	*       {
+	*           set LSB of quotient
+	*           remainder -= divisor;
+	*       }
+	*/
+	bltu r13, r5, div_skip
+	ori r3, r3, 1
+	sub r13, r13, r5
+div_skip:
+
+	/*
+	*   }
+	*/
+	subi r14, r14, 1
+	bne r14, zero, divide_loop
+
+
+	/* Now
+	* r3 = quotient
+	* r4 = 0x25 for div, 0x24 for divu
+	* r6 = 4*C
+	* r17 = MSB contains sign of quotient
+	*/
+
+
+	/*
+	*  Conditionally negate signed quotient.  If quotient is unsigned,
+	*  the sign already is initialized to 0.
+	*/
+	bge r17, zero, quotient_is_nonnegative
+	sub r3, zero, r3		/* -r3 */
+	quotient_is_nonnegative:
+
+
+	/*
+	*  Final quotient is in r3.
+	*/
+	add r6, r6, sp
+	stw r3, 0(r6)	/* write quotient to stack */
+	br restore_registers
+
+
+
+
+	/* MULTIPLICATION
+	*
+	* A "product" is the number that one gets by summing a "multiplicand"
+	* several times.  The "multiplier" specifies the number of copies of the
+	* multiplicand that are summed.
+	*
+	* Actual multiplication algorithms don't use repeated addition, however.
+	* Shift-and-add algorithms get the same answer as repeated addition, and
+	* they are faster.  To compute the lower half of a product (pppp below)
+	* one shifts the product left before adding in each of the partial
+	* products (a * mmmm) through (d * mmmm).
+	*
+	* To compute the upper half of a product (PPPP below), one adds in the
+	* partial products (d * mmmm) through (a * mmmm), each time following
+	* the add by a right shift of the product.
+	*
+	*     mmmm
+	*   * abcd
+	*   ------
+	*     ####  = d * mmmm
+	*    ####   = c * mmmm
+	*   ####    = b * mmmm
+	*  ####     = a * mmmm
+	* --------
+	* PPPPpppp
+	*
+	* The example above shows 4 partial products.  Computing actual Nios II
+	* products requires 32 partials.
+	*
+	* It is possible to compute the result of mulxsu from the result of
+	* mulxuu because the only difference between the results of these two
+	* opcodes is the value of the partial product associated with the sign
+	* bit of rA.
+	*
+	*   mulxsu = mulxuu - (rA < 0) ? rB : 0;
+	*
+	* It is possible to compute the result of mulxss from the result of
+	* mulxsu because the only difference between the results of these two
+	* opcodes is the value of the partial product associated with the sign
+	* bit of rB.
+	*
+	*   mulxss = mulxsu - (rB < 0) ? rA : 0;
+	*
+	*/
+
+mul_immed:
+	/* Opcode is muli.  Change it into mul for remainder of algorithm. */
+	mov r6, r5		/* Field B is dest register, not field C. */
+	mov r5, r4		/* Field IMM16 is src2, not field B. */
+	movi r4, 0x27		/* OPX of mul is 0x27 */
+
+multiply:
+	/* Initialize the multiplication loop. */
+	movi r9, 0	/* mul_product    = 0 */
+	movi r10, 0	/* mulxuu_product = 0 */
+	mov r11, r5	/* save original multiplier for mulxsu and mulxss */
+	mov r12, r5	/* mulxuu_multiplier (will be shifted) */
+	movi r16, 1	/* used to create "rori B,A,1" from "ror B,A,r16" */
+
+	/* Now
+	* r3 = multiplicand
+	* r5 = mul_multiplier
+	* r6 = 4 * dest_register (used later as offset to sp)
+	* r7 = temp
+	* r9 = mul_product
+	* r10 = mulxuu_product
+	* r11 = original multiplier
+	* r12 = mulxuu_multiplier
+	* r14 = loop counter (already initialized)
+	* r16 = 1
+	*/
+
+
+	/*
+	*   for (count = 32; count > 0; --count)
+	*   {
+	*/
+multiply_loop:
+
+	/*
+	*       mul_product <<= 1;
+	*       lsb = multiplier & 1;
+	*/
+	slli r9, r9, 1
+	andi r7, r12, 1
+
+	/*
+	*       if (lsb == 1)
+	*       {
+	*           mulxuu_product += multiplicand;
+	*       }
+	*/
+	beq r7, zero, mulx_skip
+	add r10, r10, r3
+	cmpltu r7, r10, r3 /* Save the carry from the MSB of mulxuu_product. */
+	ror r7, r7, r16	/* r7 = 0x80000000 on carry, or else 0x00000000 */
+mulx_skip:
+
+	/*
+	*       if (MSB of mul_multiplier == 1)
+	*       {
+	*           mul_product += multiplicand;
+	*       }
+	*/
+	bge r5, zero, mul_skip
+	add r9, r9, r3
+mul_skip:
+
+	/*
+	*       mulxuu_product >>= 1;           logical shift
+	*       mul_multiplier <<= 1;           done with MSB
+	*       mulx_multiplier >>= 1;          done with LSB
+	*/
+	srli r10, r10, 1
+	or r10, r10, r7		/* OR in the saved carry bit. */
+	slli r5, r5, 1
+	srli r12, r12, 1
+
+
+	/*
+	*   }
+	*/
+	subi r14, r14, 1
+	bne r14, zero, multiply_loop
+
+
+	/*
+	*  Multiply emulation loop done.
+	*/
+
+	/* Now
+	* r3 = multiplicand
+	* r4 = OPX
+	* r6 = 4 * dest_register (used later as offset to sp)
+	* r7 = temp
+	* r9 = mul_product
+	* r10 = mulxuu_product
+	* r11 = original multiplier
+	*/
+
+
+	/* Calculate address for result from 4 * dest_register */
+	add r6, r6, sp
+
+
+	/*
+	* Select/compute the result based on OPX.
+	*/
+
+
+	/* OPX == mul?  Then store. */
+	xori r7, r4, 0x27
+	beq r7, zero, store_product
+
+	/* It's one of the mulx.. opcodes.  Move over the result. */
+	mov r9, r10
+
+	/* OPX == mulxuu?  Then store. */
+	xori r7, r4, 0x07
+	beq r7, zero, store_product
+
+	/* Compute mulxsu
+	 *
+	 * mulxsu = mulxuu - (rA < 0) ? rB : 0;
+	 */
+	bge r3, zero, mulxsu_skip
+	sub r9, r9, r11
+mulxsu_skip:
+
+	/* OPX == mulxsu?  Then store. */
+	xori r7, r4, 0x17
+	beq r7, zero, store_product
+
+	/* Compute mulxss
+	 *
+	 * mulxss = mulxsu - (rB < 0) ? rA : 0;
+	 */
+	bge r11,zero,mulxss_skip
+	sub r9, r9, r3
+mulxss_skip:
+	/* At this point, assume that OPX is mulxss, so store*/
+
+
+store_product:
+	stw r9, 0(r6)
+
+
+restore_registers:
+			/* No need to restore r0. */
+	ldw r5, 100(sp)
+	wrctl estatus, r5
+
+	ldw r1, 4(sp)
+	ldw r2, 8(sp)
+	ldw r3, 12(sp)
+	ldw r4, 16(sp)
+	ldw r5, 20(sp)
+	ldw r6, 24(sp)
+	ldw r7, 28(sp)
+	ldw r8, 32(sp)
+	ldw r9, 36(sp)
+	ldw r10, 40(sp)
+	ldw r11, 44(sp)
+	ldw r12, 48(sp)
+	ldw r13, 52(sp)
+	ldw r14, 56(sp)
+	ldw r15, 60(sp)
+	ldw r16, 64(sp)
+	ldw r17, 68(sp)
+	ldw r18, 72(sp)
+	ldw r19, 76(sp)
+	ldw r20, 80(sp)
+	ldw r21, 84(sp)
+	ldw r22, 88(sp)
+	ldw r23, 92(sp)
+			/* Does not need to restore et */
+	ldw gp, 104(sp)
+
+	ldw fp, 112(sp)
+	ldw ea, 116(sp)
+	ldw ra, 120(sp)
+	ldw sp, 108(sp)	/* last restore sp */
+	eret
+
+.set at
+.set break
diff --git a/arch/nios2/kernel/irq.c b/arch/nios2/kernel/irq.c
new file mode 100644
index 000000000..6b7890e5f
--- /dev/null
+++ b/arch/nios2/kernel/irq.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * based on irq.c from m68k which is:
+ *
+ * Copyright (C) 2007 Greg Ungerer <gerg@snapgear.com>
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+
+static u32 ienable;
+
+asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
+{
+	struct pt_regs *oldregs = set_irq_regs(regs);
+
+	irq_enter();
+	generic_handle_domain_irq(NULL, hwirq);
+	irq_exit();
+
+	set_irq_regs(oldregs);
+}
+
+static void chip_unmask(struct irq_data *d)
+{
+	ienable |= (1 << d->hwirq);
+	WRCTL(CTL_IENABLE, ienable);
+}
+
+static void chip_mask(struct irq_data *d)
+{
+	ienable &= ~(1 << d->hwirq);
+	WRCTL(CTL_IENABLE, ienable);
+}
+
+static struct irq_chip m_irq_chip = {
+	.name		= "NIOS2-INTC",
+	.irq_unmask	= chip_unmask,
+	.irq_mask	= chip_mask,
+};
+
+static int irq_map(struct irq_domain *h, unsigned int virq,
+				irq_hw_number_t hw_irq_num)
+{
+	irq_set_chip_and_handler(virq, &m_irq_chip, handle_level_irq);
+
+	return 0;
+}
+
+static const struct irq_domain_ops irq_ops = {
+	.map	= irq_map,
+	.xlate	= irq_domain_xlate_onecell,
+};
+
+void __init init_IRQ(void)
+{
+	struct irq_domain *domain;
+	struct device_node *node;
+
+	node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.0");
+	if (!node)
+		node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.1");
+
+	BUG_ON(!node);
+
+	domain = irq_domain_add_linear(node, NIOS2_CPU_NR_IRQS, &irq_ops, NULL);
+	BUG_ON(!domain);
+
+	irq_set_default_host(domain);
+	of_node_put(node);
+	/* Load the initial ienable value */
+	ienable = RDCTL(CTL_IENABLE);
+}
diff --git a/arch/nios2/kernel/kgdb.c b/arch/nios2/kernel/kgdb.c
new file mode 100644
index 000000000..d0963fcb1
--- /dev/null
+++ b/arch/nios2/kernel/kgdb.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Nios2 KGDB support
+ *
+ * Copyright (C) 2015 Altera Corporation
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * Based on the code posted by Kazuyasu on the Altera Forum at:
+ * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20
+ */
+#include <linux/ptrace.h>
+#include <linux/kgdb.h>
+#include <linux/kdebug.h>
+#include <linux/io.h>
+
+static int wait_for_remote_debugger;
+
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
+{
+	{ "zero", GDB_SIZEOF_REG, -1 },
+	{ "at", GDB_SIZEOF_REG, offsetof(struct pt_regs, r1) },
+	{ "r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, r2) },
+	{ "r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, r3) },
+	{ "r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, r4) },
+	{ "r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, r5) },
+	{ "r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, r6) },
+	{ "r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, r7) },
+	{ "r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, r8) },
+	{ "r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, r9) },
+	{ "r10", GDB_SIZEOF_REG, offsetof(struct pt_regs, r10) },
+	{ "r11", GDB_SIZEOF_REG, offsetof(struct pt_regs, r11) },
+	{ "r12", GDB_SIZEOF_REG, offsetof(struct pt_regs, r12) },
+	{ "r13", GDB_SIZEOF_REG, offsetof(struct pt_regs, r13) },
+	{ "r14", GDB_SIZEOF_REG, offsetof(struct pt_regs, r14) },
+	{ "r15", GDB_SIZEOF_REG, offsetof(struct pt_regs, r15) },
+	{ "r16", GDB_SIZEOF_REG, -1 },
+	{ "r17", GDB_SIZEOF_REG, -1 },
+	{ "r18", GDB_SIZEOF_REG, -1 },
+	{ "r19", GDB_SIZEOF_REG, -1 },
+	{ "r20", GDB_SIZEOF_REG, -1 },
+	{ "r21", GDB_SIZEOF_REG, -1 },
+	{ "r22", GDB_SIZEOF_REG, -1 },
+	{ "r23", GDB_SIZEOF_REG, -1 },
+	{ "et", GDB_SIZEOF_REG, -1 },
+	{ "bt", GDB_SIZEOF_REG, -1 },
+	{ "gp", GDB_SIZEOF_REG, offsetof(struct pt_regs, gp) },
+	{ "sp", GDB_SIZEOF_REG, offsetof(struct pt_regs, sp) },
+	{ "fp", GDB_SIZEOF_REG, offsetof(struct pt_regs, fp) },
+	{ "ea", GDB_SIZEOF_REG, -1 },
+	{ "ba", GDB_SIZEOF_REG, -1 },
+	{ "ra", GDB_SIZEOF_REG, offsetof(struct pt_regs, ra) },
+	{ "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, ea) },
+	{ "status", GDB_SIZEOF_REG, -1 },
+	{ "estatus", GDB_SIZEOF_REG, offsetof(struct pt_regs, estatus) },
+	{ "bstatus", GDB_SIZEOF_REG, -1 },
+	{ "ienable", GDB_SIZEOF_REG, -1 },
+	{ "ipending", GDB_SIZEOF_REG, -1},
+	{ "cpuid", GDB_SIZEOF_REG, -1 },
+	{ "ctl6", GDB_SIZEOF_REG, -1 },
+	{ "exception", GDB_SIZEOF_REG, -1 },
+	{ "pteaddr", GDB_SIZEOF_REG, -1 },
+	{ "tlbacc", GDB_SIZEOF_REG, -1 },
+	{ "tlbmisc", GDB_SIZEOF_REG, -1 },
+	{ "eccinj", GDB_SIZEOF_REG, -1 },
+	{ "badaddr", GDB_SIZEOF_REG, -1 },
+	{ "config", GDB_SIZEOF_REG, -1 },
+	{ "mpubase", GDB_SIZEOF_REG, -1 },
+	{ "mpuacc", GDB_SIZEOF_REG, -1 },
+};
+
+char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return NULL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,
+		       dbg_reg_def[regno].size);
+	else
+		memset(mem, 0, dbg_reg_def[regno].size);
+
+	return dbg_reg_def[regno].name;
+}
+
+int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return -EINVAL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,
+		       dbg_reg_def[regno].size);
+
+	return 0;
+}
+
+void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
+{
+	memset((char *)gdb_regs, 0, NUMREGBYTES);
+	gdb_regs[GDB_SP] = p->thread.kregs->sp;
+	gdb_regs[GDB_PC] = p->thread.kregs->ea;
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+	regs->ea = pc;
+}
+
+int kgdb_arch_handle_exception(int vector, int signo, int err_code,
+				char *remcom_in_buffer, char *remcom_out_buffer,
+				struct pt_regs *regs)
+{
+	char *ptr;
+	unsigned long addr;
+
+	switch (remcom_in_buffer[0]) {
+	case 's':
+	case 'c':
+		/* handle the optional parameters */
+		ptr = &remcom_in_buffer[1];
+		if (kgdb_hex2long(&ptr, &addr))
+			regs->ea = addr;
+
+		return 0;
+	}
+
+	return -1; /* this means that we do not want to exit from the handler */
+}
+
+asmlinkage void kgdb_breakpoint_c(struct pt_regs *regs)
+{
+	/*
+	 * The breakpoint entry code has moved the PC on by 4 bytes, so we must
+	 * move it back.  This could be done on the host but we do it here
+	 */
+	if (!wait_for_remote_debugger)
+		regs->ea -= 4;
+	else	/* pass the first trap 30 code */
+		wait_for_remote_debugger = 0;
+
+	kgdb_handle_exception(30, SIGTRAP, 0, regs);
+}
+
+int kgdb_arch_init(void)
+{
+	wait_for_remote_debugger = 1;
+	return 0;
+}
+
+void kgdb_arch_exit(void)
+{
+	/* Nothing to do */
+}
+
+const struct kgdb_arch arch_kgdb_ops = {
+	/* Breakpoint instruction: trap 30 */
+	.gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 },
+};
diff --git a/arch/nios2/kernel/misaligned.c b/arch/nios2/kernel/misaligned.c
new file mode 100644
index 000000000..23e0544e1
--- /dev/null
+++ b/arch/nios2/kernel/misaligned.c
@@ -0,0 +1,238 @@
+/*
+ *  linux/arch/nios2/kernel/misaligned.c
+ *
+ *  basic emulation for mis-aligned accesses on the NIOS II cpu
+ *  modelled after the version for arm in arm/alignment.c
+ *
+ *  Brad Parker <brad@heeltoe.com>
+ *  Copyright (C) 2010 Ambient Corporation
+ *  Copyright (c) 2010 Altera Corporation, San Jose, California, USA.
+ *  Copyright (c) 2010 Arrow Electronics, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of
+ * this archive for more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/seq_file.h>
+
+#include <asm/traps.h>
+#include <asm/unaligned.h>
+
+/* instructions we emulate */
+#define INST_LDHU	0x0b
+#define INST_STH	0x0d
+#define INST_LDH	0x0f
+#define INST_STW	0x15
+#define INST_LDW	0x17
+
+static unsigned int ma_usermode;
+#define UM_WARN		0x01
+#define UM_FIXUP	0x02
+#define UM_SIGNAL	0x04
+#define KM_WARN		0x08
+
+/* see arch/nios2/include/asm/ptrace.h */
+static u8 sys_stack_frame_reg_offset[] = {
+	/* struct pt_regs */
+	8, 9, 10, 11, 12, 13, 14, 15, 1, 2, 3, 4, 5, 6, 7, 0,
+	/* struct switch_stack */
+	16, 17, 18, 19, 20, 21, 22, 23, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+static int reg_offsets[32];
+
+static inline u32 get_reg_val(struct pt_regs *fp, int reg)
+{
+	u8 *p = ((u8 *)fp) + reg_offsets[reg];
+	return *(u32 *)p;
+}
+
+static inline void put_reg_val(struct pt_regs *fp, int reg, u32 val)
+{
+	u8 *p = ((u8 *)fp) + reg_offsets[reg];
+	*(u32 *)p = val;
+}
+
+/*
+ * (mis)alignment handler
+ */
+asmlinkage void handle_unaligned_c(struct pt_regs *fp, int cause)
+{
+	u32 isn, addr, val;
+	int in_kernel;
+	u8 a, b, d0, d1, d2, d3;
+	s16 imm16;
+	unsigned int fault;
+
+	/* back up one instruction */
+	fp->ea -= 4;
+
+	if (fixup_exception(fp)) {
+		return;
+	}
+
+	in_kernel = !user_mode(fp);
+
+	isn = *(unsigned long *)(fp->ea);
+
+	fault = 0;
+
+	/* do fixup if in kernel or mode turned on */
+	if (in_kernel || (ma_usermode & UM_FIXUP)) {
+		/* decompose instruction */
+		a = (isn >> 27) & 0x1f;
+		b = (isn >> 22) & 0x1f;
+		imm16 = (isn >> 6) & 0xffff;
+		addr = get_reg_val(fp, a) + imm16;
+
+		/* do fixup to saved registers */
+		switch (isn & 0x3f) {
+		case INST_LDHU:
+			fault |= __get_user(d0, (u8 *)(addr+0));
+			fault |= __get_user(d1, (u8 *)(addr+1));
+			val = (d1 << 8) | d0;
+			put_reg_val(fp, b, val);
+			break;
+		case INST_STH:
+			val = get_reg_val(fp, b);
+			d1 = val >> 8;
+			d0 = val >> 0;
+			if (in_kernel) {
+				*(u8 *)(addr+0) = d0;
+				*(u8 *)(addr+1) = d1;
+			} else {
+				fault |= __put_user(d0, (u8 *)(addr+0));
+				fault |= __put_user(d1, (u8 *)(addr+1));
+			}
+			break;
+		case INST_LDH:
+			fault |= __get_user(d0, (u8 *)(addr+0));
+			fault |= __get_user(d1, (u8 *)(addr+1));
+			val = (short)((d1 << 8) | d0);
+			put_reg_val(fp, b, val);
+			break;
+		case INST_STW:
+			val = get_reg_val(fp, b);
+			d3 = val >> 24;
+			d2 = val >> 16;
+			d1 = val >> 8;
+			d0 = val >> 0;
+			if (in_kernel) {
+				*(u8 *)(addr+0) = d0;
+				*(u8 *)(addr+1) = d1;
+				*(u8 *)(addr+2) = d2;
+				*(u8 *)(addr+3) = d3;
+			} else {
+				fault |= __put_user(d0, (u8 *)(addr+0));
+				fault |= __put_user(d1, (u8 *)(addr+1));
+				fault |= __put_user(d2, (u8 *)(addr+2));
+				fault |= __put_user(d3, (u8 *)(addr+3));
+			}
+			break;
+		case INST_LDW:
+			fault |= __get_user(d0, (u8 *)(addr+0));
+			fault |= __get_user(d1, (u8 *)(addr+1));
+			fault |= __get_user(d2, (u8 *)(addr+2));
+			fault |= __get_user(d3, (u8 *)(addr+3));
+			val = (d3 << 24) | (d2 << 16) | (d1 << 8) | d0;
+			put_reg_val(fp, b, val);
+			break;
+		}
+	}
+
+	addr = RDCTL(CTL_BADADDR);
+	cause >>= 2;
+
+	if (fault) {
+		if (in_kernel) {
+			pr_err("fault during kernel misaligned fixup @ %#lx; addr 0x%08x; isn=0x%08x\n",
+				fp->ea, (unsigned int)addr,
+				(unsigned int)isn);
+		} else {
+			pr_err("fault during user misaligned fixup @ %#lx; isn=%08x addr=0x%08x sp=0x%08lx pid=%d\n",
+				fp->ea,
+				(unsigned int)isn, addr, fp->sp,
+				current->pid);
+
+			_exception(SIGSEGV, fp, SEGV_MAPERR, fp->ea);
+			return;
+		}
+	}
+
+	/*
+	 * kernel mode -
+	 *  note exception and skip bad instruction (return)
+	 */
+	if (in_kernel) {
+		fp->ea += 4;
+
+		if (ma_usermode & KM_WARN) {
+			pr_err("kernel unaligned access @ %#lx; BADADDR 0x%08x; cause=%d, isn=0x%08x\n",
+				fp->ea,
+				(unsigned int)addr, cause,
+				(unsigned int)isn);
+			/* show_regs(fp); */
+		}
+
+		return;
+	}
+
+	/*
+	 * user mode -
+	 *  possibly warn,
+	 *  possibly send SIGBUS signal to process
+	 */
+	if (ma_usermode & UM_WARN) {
+		pr_err("user unaligned access @ %#lx; isn=0x%08lx ea=0x%08lx ra=0x%08lx sp=0x%08lx\n",
+			(unsigned long)addr, (unsigned long)isn,
+			fp->ea, fp->ra, fp->sp);
+	}
+
+	if (ma_usermode & UM_SIGNAL)
+		_exception(SIGBUS, fp, BUS_ADRALN, fp->ea);
+	else
+		fp->ea += 4;	/* else advance */
+}
+
+static void __init misaligned_calc_reg_offsets(void)
+{
+	int i, r, offset;
+
+	/* pre-calc offsets of registers on sys call stack frame */
+	offset = 0;
+
+	/* struct pt_regs */
+	for (i = 0; i < 16; i++) {
+		r = sys_stack_frame_reg_offset[i];
+		reg_offsets[r] = offset;
+		offset += 4;
+	}
+
+	/* struct switch_stack */
+	offset = -sizeof(struct switch_stack);
+	for (i = 16; i < 32; i++) {
+		r = sys_stack_frame_reg_offset[i];
+		reg_offsets[r] = offset;
+		offset += 4;
+	}
+}
+
+
+static int __init misaligned_init(void)
+{
+	/* default mode - silent fix */
+	ma_usermode = UM_FIXUP | KM_WARN;
+
+	misaligned_calc_reg_offsets();
+
+	return 0;
+}
+
+fs_initcall(misaligned_init);
diff --git a/arch/nios2/kernel/module.c b/arch/nios2/kernel/module.c
new file mode 100644
index 000000000..76e0a42d6
--- /dev/null
+++ b/arch/nios2/kernel/module.c
@@ -0,0 +1,137 @@
+/*
+ * Kernel module support for Nios II.
+ *
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *   Written by Wentao Xu <xuwentao@microtronix.com>
+ * Copyright (C) 2001, 2003 Rusty Russell
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+
+#include <asm/cacheflush.h>
+
+/*
+ * Modules should NOT be allocated with kmalloc for (obvious) reasons.
+ * But we do it for now to avoid relocation issues. CALL26/PCREL26 cannot reach
+ * from 0x80000000 (vmalloc area) to 0xc00000000 (kernel) (kmalloc returns
+ * addresses in 0xc0000000)
+ */
+void *module_alloc(unsigned long size)
+{
+	if (size == 0)
+		return NULL;
+	return kmalloc(size, GFP_KERNEL);
+}
+
+/* Free memory returned from module_alloc */
+void module_memfree(void *module_region)
+{
+	kfree(module_region);
+}
+
+int apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
+			unsigned int symindex, unsigned int relsec,
+			struct module *mod)
+{
+	unsigned int i;
+	Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
+
+	pr_debug("Applying relocate section %u to %u\n", relsec,
+		 sechdrs[relsec].sh_info);
+
+	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
+		/* This is where to make the change */
+		uint32_t word;
+		uint32_t *loc
+			= ((void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+			   + rela[i].r_offset);
+		/* This is the symbol it is referring to.  Note that all
+		   undefined symbols have been resolved.  */
+		Elf32_Sym *sym
+			= ((Elf32_Sym *)sechdrs[symindex].sh_addr
+				+ ELF32_R_SYM(rela[i].r_info));
+		uint32_t v = sym->st_value + rela[i].r_addend;
+
+		pr_debug("reltype %d 0x%x name:<%s>\n",
+			ELF32_R_TYPE(rela[i].r_info),
+			rela[i].r_offset, strtab + sym->st_name);
+
+		switch (ELF32_R_TYPE(rela[i].r_info)) {
+		case R_NIOS2_NONE:
+			break;
+		case R_NIOS2_BFD_RELOC_32:
+			*loc += v;
+			break;
+		case R_NIOS2_PCREL16:
+			v -= (uint32_t)loc + 4;
+			if ((int32_t)v > 0x7fff ||
+				(int32_t)v < -(int32_t)0x8000) {
+				pr_err("module %s: relocation overflow\n",
+					mod->name);
+				return -ENOEXEC;
+			}
+			word = *loc;
+			*loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
+				(word & 0x3f);
+			break;
+		case R_NIOS2_CALL26:
+			if (v & 3) {
+				pr_err("module %s: dangerous relocation\n",
+					mod->name);
+				return -ENOEXEC;
+			}
+			if ((v >> 28) != ((uint32_t)loc >> 28)) {
+				pr_err("module %s: relocation overflow\n",
+					mod->name);
+				return -ENOEXEC;
+			}
+			*loc = (*loc & 0x3f) | ((v >> 2) << 6);
+			break;
+		case R_NIOS2_HI16:
+			word = *loc;
+			*loc = ((((word >> 22) << 16) |
+				((v >> 16) & 0xffff)) << 6) | (word & 0x3f);
+			break;
+		case R_NIOS2_LO16:
+			word = *loc;
+			*loc = ((((word >> 22) << 16) | (v & 0xffff)) << 6) |
+					(word & 0x3f);
+			break;
+		case R_NIOS2_HIADJ16:
+			{
+				Elf32_Addr word2;
+
+				word = *loc;
+				word2 = ((v >> 16) + ((v >> 15) & 1)) & 0xffff;
+				*loc = ((((word >> 22) << 16) | word2) << 6) |
+						(word & 0x3f);
+			}
+			break;
+
+		default:
+			pr_err("module %s: Unknown reloc: %u\n",
+				mod->name, ELF32_R_TYPE(rela[i].r_info));
+			return -ENOEXEC;
+		}
+	}
+
+	return 0;
+}
+
+int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
+			struct module *me)
+{
+	flush_cache_all();
+	return 0;
+}
diff --git a/arch/nios2/kernel/nios2_ksyms.c b/arch/nios2/kernel/nios2_ksyms.c
new file mode 100644
index 000000000..54f7b23df
--- /dev/null
+++ b/arch/nios2/kernel/nios2_ksyms.c
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/string.h>
+#include <linux/pgtable.h>
+
+#include <asm/cacheflush.h>
+
+/* string functions */
+
+EXPORT_SYMBOL(memcpy);
+EXPORT_SYMBOL(memset);
+EXPORT_SYMBOL(memmove);
+
+/* memory management */
+
+EXPORT_SYMBOL(empty_zero_page);
+EXPORT_SYMBOL(flush_icache_range);
+
+/*
+ * libgcc functions - functions that are used internally by the
+ * compiler...  (prototypes are not correct though, but that
+ * doesn't really matter since they're not versioned).
+ */
+#define DECLARE_EXPORT(name)	extern void name(void); EXPORT_SYMBOL(name)
+
+DECLARE_EXPORT(__gcc_bcmp);
+DECLARE_EXPORT(__divsi3);
+DECLARE_EXPORT(__moddi3);
+DECLARE_EXPORT(__modsi3);
+DECLARE_EXPORT(__udivmoddi4);
+DECLARE_EXPORT(__udivsi3);
+DECLARE_EXPORT(__umoddi3);
+DECLARE_EXPORT(__umodsi3);
+DECLARE_EXPORT(__muldi3);
+DECLARE_EXPORT(__ucmpdi2);
+DECLARE_EXPORT(__lshrdi3);
+DECLARE_EXPORT(__ashldi3);
+DECLARE_EXPORT(__ashrdi3);
diff --git a/arch/nios2/kernel/process.c b/arch/nios2/kernel/process.c
new file mode 100644
index 000000000..29593b985
--- /dev/null
+++ b/arch/nios2/kernel/process.c
@@ -0,0 +1,269 @@
+/*
+ * Architecture-dependent parts of process handling.
+ *
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm_types.h>
+#include <linux/tick.h>
+#include <linux/uaccess.h>
+
+#include <asm/unistd.h>
+#include <asm/traps.h>
+#include <asm/cpuinfo.h>
+
+asmlinkage void ret_from_fork(void);
+asmlinkage void ret_from_kernel_thread(void);
+
+void (*pm_power_off)(void) = NULL;
+EXPORT_SYMBOL(pm_power_off);
+
+void arch_cpu_idle(void)
+{
+	raw_local_irq_enable();
+}
+
+/*
+ * The development boards have no way to pull a board reset. Just jump to the
+ * cpu reset address and let the boot loader or the code in head.S take care of
+ * resetting peripherals.
+ */
+void machine_restart(char *__unused)
+{
+	pr_notice("Machine restart (%08x)...\n", cpuinfo.reset_addr);
+	local_irq_disable();
+	__asm__ __volatile__ (
+	"jmp	%0\n\t"
+	:
+	: "r" (cpuinfo.reset_addr)
+	: "r4");
+}
+
+void machine_halt(void)
+{
+	pr_notice("Machine halt...\n");
+	local_irq_disable();
+	for (;;)
+		;
+}
+
+/*
+ * There is no way to power off the development boards. So just spin for now. If
+ * we ever have a way of resetting a board using a GPIO we should add that here.
+ */
+void machine_power_off(void)
+{
+	pr_notice("Machine power off...\n");
+	local_irq_disable();
+	for (;;)
+		;
+}
+
+void show_regs(struct pt_regs *regs)
+{
+	pr_notice("\n");
+	show_regs_print_info(KERN_DEFAULT);
+
+	pr_notice("r1: %08lx r2: %08lx r3: %08lx r4: %08lx\n",
+		regs->r1,  regs->r2,  regs->r3,  regs->r4);
+
+	pr_notice("r5: %08lx r6: %08lx r7: %08lx r8: %08lx\n",
+		regs->r5,  regs->r6,  regs->r7,  regs->r8);
+
+	pr_notice("r9: %08lx r10: %08lx r11: %08lx r12: %08lx\n",
+		regs->r9,  regs->r10, regs->r11, regs->r12);
+
+	pr_notice("r13: %08lx r14: %08lx r15: %08lx\n",
+		regs->r13, regs->r14, regs->r15);
+
+	pr_notice("ra: %08lx fp:  %08lx sp: %08lx gp: %08lx\n",
+		regs->ra,  regs->fp,  regs->sp,  regs->gp);
+
+	pr_notice("ea: %08lx estatus: %08lx\n",
+		regs->ea,  regs->estatus);
+}
+
+void flush_thread(void)
+{
+}
+
+int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
+{
+	unsigned long clone_flags = args->flags;
+	unsigned long usp = args->stack;
+	unsigned long tls = args->tls;
+	struct pt_regs *childregs = task_pt_regs(p);
+	struct pt_regs *regs;
+	struct switch_stack *stack;
+	struct switch_stack *childstack =
+		((struct switch_stack *)childregs) - 1;
+
+	if (unlikely(args->fn)) {
+		memset(childstack, 0,
+			sizeof(struct switch_stack) + sizeof(struct pt_regs));
+
+		childstack->r16 = (unsigned long) args->fn;
+		childstack->r17 = (unsigned long) args->fn_arg;
+		childstack->ra = (unsigned long) ret_from_kernel_thread;
+		childregs->estatus = STATUS_PIE;
+		childregs->sp = (unsigned long) childstack;
+
+		p->thread.ksp = (unsigned long) childstack;
+		p->thread.kregs = childregs;
+		return 0;
+	}
+
+	regs = current_pt_regs();
+	*childregs = *regs;
+	childregs->r2 = 0;	/* Set the return value for the child. */
+	childregs->r7 = 0;
+
+	stack = ((struct switch_stack *) regs) - 1;
+	*childstack = *stack;
+	childstack->ra = (unsigned long)ret_from_fork;
+	p->thread.kregs = childregs;
+	p->thread.ksp = (unsigned long) childstack;
+
+	if (usp)
+		childregs->sp = usp;
+
+	/* Initialize tls register. */
+	if (clone_flags & CLONE_SETTLS)
+		childstack->r23 = tls;
+
+	return 0;
+}
+
+/*
+ *	Generic dumping code. Used for panic and debug.
+ */
+void dump(struct pt_regs *fp)
+{
+	unsigned long	*sp;
+	unsigned char	*tp;
+	int		i;
+
+	pr_emerg("\nCURRENT PROCESS:\n\n");
+	pr_emerg("COMM=%s PID=%d\n", current->comm, current->pid);
+
+	if (current->mm) {
+		pr_emerg("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
+			(int) current->mm->start_code,
+			(int) current->mm->end_code,
+			(int) current->mm->start_data,
+			(int) current->mm->end_data,
+			(int) current->mm->end_data,
+			(int) current->mm->brk);
+		pr_emerg("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
+			(int) current->mm->start_stack,
+			(int)(((unsigned long) current) + THREAD_SIZE));
+	}
+
+	pr_emerg("PC: %08lx\n", fp->ea);
+	pr_emerg("SR: %08lx    SP: %08lx\n",
+		(long) fp->estatus, (long) fp);
+
+	pr_emerg("r1: %08lx    r2: %08lx    r3: %08lx\n",
+		fp->r1, fp->r2, fp->r3);
+
+	pr_emerg("r4: %08lx    r5: %08lx    r6: %08lx    r7: %08lx\n",
+		fp->r4, fp->r5, fp->r6, fp->r7);
+	pr_emerg("r8: %08lx    r9: %08lx    r10: %08lx    r11: %08lx\n",
+		fp->r8, fp->r9, fp->r10, fp->r11);
+	pr_emerg("r12: %08lx  r13: %08lx    r14: %08lx    r15: %08lx\n",
+		fp->r12, fp->r13, fp->r14, fp->r15);
+	pr_emerg("or2: %08lx   ra: %08lx     fp: %08lx    sp: %08lx\n",
+		fp->orig_r2, fp->ra, fp->fp, fp->sp);
+	pr_emerg("\nUSP: %08x   TRAPFRAME: %08x\n",
+		(unsigned int) fp->sp, (unsigned int) fp);
+
+	pr_emerg("\nCODE:");
+	tp = ((unsigned char *) fp->ea) - 0x20;
+	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
+		if ((i % 0x10) == 0)
+			pr_emerg("\n%08x: ", (int) (tp + i));
+		pr_emerg("%08x ", (int) *sp++);
+	}
+	pr_emerg("\n");
+
+	pr_emerg("\nKERNEL STACK:");
+	tp = ((unsigned char *) fp) - 0x40;
+	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
+		if ((i % 0x10) == 0)
+			pr_emerg("\n%08x: ", (int) (tp + i));
+		pr_emerg("%08x ", (int) *sp++);
+	}
+	pr_emerg("\n");
+	pr_emerg("\n");
+
+	pr_emerg("\nUSER STACK:");
+	tp = (unsigned char *) (fp->sp - 0x10);
+	for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) {
+		if ((i % 0x10) == 0)
+			pr_emerg("\n%08x: ", (int) (tp + i));
+		pr_emerg("%08x ", (int) *sp++);
+	}
+	pr_emerg("\n\n");
+}
+
+unsigned long __get_wchan(struct task_struct *p)
+{
+	unsigned long fp, pc;
+	unsigned long stack_page;
+	int count = 0;
+
+	stack_page = (unsigned long)p;
+	fp = ((struct switch_stack *)p->thread.ksp)->fp;	/* ;dgt2 */
+	do {
+		if (fp < stack_page+sizeof(struct task_struct) ||
+			fp >= 8184+stack_page)	/* ;dgt2;tmp */
+			return 0;
+		pc = ((unsigned long *)fp)[1];
+		if (!in_sched_functions(pc))
+			return pc;
+		fp = *(unsigned long *) fp;
+	} while (count++ < 16);		/* ;dgt2;tmp */
+	return 0;
+}
+
+/*
+ * Do necessary setup to start up a newly executed thread.
+ * Will startup in user mode (status_extension = 0).
+ */
+void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
+{
+	memset((void *) regs, 0, sizeof(struct pt_regs));
+	regs->estatus = ESTATUS_EPIE | ESTATUS_EU;
+	regs->ea = pc;
+	regs->sp = sp;
+}
+
+asmlinkage int nios2_clone(unsigned long clone_flags, unsigned long newsp,
+			   int __user *parent_tidptr, int __user *child_tidptr,
+			   unsigned long tls)
+{
+	struct kernel_clone_args args = {
+		.flags		= (lower_32_bits(clone_flags) & ~CSIGNAL),
+		.pidfd		= parent_tidptr,
+		.child_tid	= child_tidptr,
+		.parent_tid	= parent_tidptr,
+		.exit_signal	= (lower_32_bits(clone_flags) & CSIGNAL),
+		.stack		= newsp,
+		.tls		= tls,
+	};
+
+	return kernel_clone(&args);
+}
diff --git a/arch/nios2/kernel/prom.c b/arch/nios2/kernel/prom.c
new file mode 100644
index 000000000..8d98af5c7
--- /dev/null
+++ b/arch/nios2/kernel/prom.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Device tree support
+ *
+ * Copyright (C) 2013, 2015 Altera Corporation
+ * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
+ *
+ * Based on MIPS support for CONFIG_OF device tree support
+ *
+ * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/io.h>
+
+#include <asm/sections.h>
+
+void __init early_init_devtree(void *params)
+{
+	__be32 *dtb = (u32 *)__dtb_start;
+#if defined(CONFIG_NIOS2_DTB_AT_PHYS_ADDR)
+	if (be32_to_cpup((__be32 *)CONFIG_NIOS2_DTB_PHYS_ADDR) ==
+		 OF_DT_HEADER) {
+		params = (void *)CONFIG_NIOS2_DTB_PHYS_ADDR;
+		early_init_dt_scan(params);
+		return;
+	}
+#endif
+	if (be32_to_cpu((__be32) *dtb) == OF_DT_HEADER)
+		params = (void *)__dtb_start;
+
+	early_init_dt_scan(params);
+}
diff --git a/arch/nios2/kernel/ptrace.c b/arch/nios2/kernel/ptrace.c
new file mode 100644
index 000000000..cd62f3107
--- /dev/null
+++ b/arch/nios2/kernel/ptrace.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2014 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#include <linux/elf.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/ptrace.h>
+#include <linux/regset.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/uaccess.h>
+#include <linux/user.h>
+
+static int genregs_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       struct membuf to)
+{
+	const struct pt_regs *regs = task_pt_regs(target);
+	const struct switch_stack *sw = (struct switch_stack *)regs - 1;
+
+	membuf_zero(&to, 4); // R0
+	membuf_write(&to, &regs->r1, 7 * 4); // R1..R7
+	membuf_write(&to, &regs->r8, 8 * 4); // R8..R15
+	membuf_write(&to, sw, 8 * 4); // R16..R23
+	membuf_zero(&to, 2 * 4); /* et and bt */
+	membuf_store(&to, regs->gp);
+	membuf_store(&to, regs->sp);
+	membuf_store(&to, regs->fp);
+	membuf_store(&to, regs->ea);
+	membuf_zero(&to, 4); // PTR_BA
+	membuf_store(&to, regs->ra);
+	membuf_store(&to, regs->ea); /* use ea for PC */
+	return membuf_zero(&to, (NUM_PTRACE_REG - PTR_PC) * 4);
+}
+
+/*
+ * Set the thread state from a regset passed in via ptrace
+ */
+static int genregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	const struct switch_stack *sw = (struct switch_stack *)regs - 1;
+	int ret = 0;
+
+#define REG_IGNORE_RANGE(START, END)		\
+	if (!ret)					\
+		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
+			START * 4, (END * 4) + 4);
+
+#define REG_IN_ONE(PTR, LOC)	\
+	if (!ret)			\
+		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
+			(void *)(PTR), LOC * 4, (LOC * 4) + 4);
+
+#define REG_IN_RANGE(PTR, START, END)	\
+	if (!ret)				\
+		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
+			(void *)(PTR), START * 4, (END * 4) + 4);
+
+	REG_IGNORE_RANGE(PTR_R0, PTR_R0);
+	REG_IN_RANGE(&regs->r1, PTR_R1, PTR_R7);
+	REG_IN_RANGE(&regs->r8, PTR_R8, PTR_R15);
+	REG_IN_RANGE(sw, PTR_R16, PTR_R23);
+	REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */
+	REG_IN_ONE(&regs->gp, PTR_GP);
+	REG_IN_ONE(&regs->sp, PTR_SP);
+	REG_IN_ONE(&regs->fp, PTR_FP);
+	REG_IN_ONE(&regs->ea, PTR_EA);
+	REG_IGNORE_RANGE(PTR_BA, PTR_BA);
+	REG_IN_ONE(&regs->ra, PTR_RA);
+	REG_IN_ONE(&regs->ea, PTR_PC); /* use ea for PC */
+	if (!ret)
+		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+					 PTR_STATUS * 4, -1);
+
+	return ret;
+}
+
+/*
+ * Define the register sets available on Nios2 under Linux
+ */
+enum nios2_regset {
+	REGSET_GENERAL,
+};
+
+static const struct user_regset nios2_regsets[] = {
+	[REGSET_GENERAL] = {
+		.core_note_type = NT_PRSTATUS,
+		.n = NUM_PTRACE_REG,
+		.size = sizeof(unsigned long),
+		.align = sizeof(unsigned long),
+		.regset_get = genregs_get,
+		.set = genregs_set,
+	}
+};
+
+static const struct user_regset_view nios2_user_view = {
+	.name = "nios2",
+	.e_machine = ELF_ARCH,
+	.ei_osabi = ELF_OSABI,
+	.regsets = nios2_regsets,
+	.n = ARRAY_SIZE(nios2_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+	return &nios2_user_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+
+}
+
+long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
+		 unsigned long data)
+{
+	return ptrace_request(child, request, addr, data);
+}
+
+asmlinkage int do_syscall_trace_enter(void)
+{
+	int ret = 0;
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE))
+		ret = ptrace_report_syscall_entry(task_pt_regs(current));
+
+	return ret;
+}
+
+asmlinkage void do_syscall_trace_exit(void)
+{
+	if (test_thread_flag(TIF_SYSCALL_TRACE))
+		ptrace_report_syscall_exit(task_pt_regs(current), 0);
+}
diff --git a/arch/nios2/kernel/setup.c b/arch/nios2/kernel/setup.c
new file mode 100644
index 000000000..40bc8fb75
--- /dev/null
+++ b/arch/nios2/kernel/setup.c
@@ -0,0 +1,197 @@
+/*
+ * Nios2-specific parts of system setup
+ *
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ * Copyright (C) 2001 Vic Phillips <vic@microtronix.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/sched/task.h>
+#include <linux/console.h>
+#include <linux/memblock.h>
+#include <linux/initrd.h>
+#include <linux/of_fdt.h>
+#include <linux/screen_info.h>
+
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/cpuinfo.h>
+
+unsigned long memory_start;
+EXPORT_SYMBOL(memory_start);
+
+unsigned long memory_end;
+EXPORT_SYMBOL(memory_end);
+
+static struct pt_regs fake_regs = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+					0, 0, 0, 0, 0, 0,
+					0};
+
+#ifdef CONFIG_VT
+struct screen_info screen_info;
+#endif
+
+/* Copy a short hook instruction sequence to the exception address */
+static inline void copy_exception_handler(unsigned int addr)
+{
+	unsigned int start = (unsigned int) exception_handler_hook;
+	volatile unsigned int tmp = 0;
+
+	if (start == addr) {
+		/* The CPU exception address already points to the handler. */
+		return;
+	}
+
+	__asm__ __volatile__ (
+		"ldw	%2,0(%0)\n"
+		"stw	%2,0(%1)\n"
+		"ldw	%2,4(%0)\n"
+		"stw	%2,4(%1)\n"
+		"ldw	%2,8(%0)\n"
+		"stw	%2,8(%1)\n"
+		"flushd	0(%1)\n"
+		"flushd	4(%1)\n"
+		"flushd	8(%1)\n"
+		"flushi %1\n"
+		"addi	%1,%1,4\n"
+		"flushi %1\n"
+		"addi	%1,%1,4\n"
+		"flushi %1\n"
+		"flushp\n"
+		: /* no output registers */
+		: "r" (start), "r" (addr), "r" (tmp)
+		: "memory"
+	);
+}
+
+/* Copy the fast TLB miss handler */
+static inline void copy_fast_tlb_miss_handler(unsigned int addr)
+{
+	unsigned int start = (unsigned int) fast_handler;
+	unsigned int end = (unsigned int) fast_handler_end;
+	volatile unsigned int tmp = 0;
+
+	__asm__ __volatile__ (
+		"1:\n"
+		"	ldw	%3,0(%0)\n"
+		"	stw	%3,0(%1)\n"
+		"	flushd	0(%1)\n"
+		"	flushi	%1\n"
+		"	flushp\n"
+		"	addi	%0,%0,4\n"
+		"	addi	%1,%1,4\n"
+		"	bne	%0,%2,1b\n"
+		: /* no output registers */
+		: "r" (start), "r" (addr), "r" (end), "r" (tmp)
+		: "memory"
+	);
+}
+
+/*
+ * save args passed from u-boot, called from head.S
+ *
+ * @r4: NIOS magic
+ * @r5: initrd start
+ * @r6: initrd end or fdt
+ * @r7: kernel command line
+ */
+asmlinkage void __init nios2_boot_init(unsigned r4, unsigned r5, unsigned r6,
+				       unsigned r7)
+{
+	unsigned dtb_passed = 0;
+	char cmdline_passed[COMMAND_LINE_SIZE] __maybe_unused = { 0, };
+
+#if defined(CONFIG_NIOS2_PASS_CMDLINE)
+	if (r4 == 0x534f494e) { /* r4 is magic NIOS */
+#if defined(CONFIG_BLK_DEV_INITRD)
+		if (r5) { /* initramfs */
+			initrd_start = r5;
+			initrd_end = r6;
+		}
+#endif /* CONFIG_BLK_DEV_INITRD */
+		dtb_passed = r6;
+
+		if (r7)
+			strlcpy(cmdline_passed, (char *)r7, COMMAND_LINE_SIZE);
+	}
+#endif
+
+	early_init_devtree((void *)dtb_passed);
+
+#ifndef CONFIG_CMDLINE_FORCE
+	if (cmdline_passed[0])
+		strlcpy(boot_command_line, cmdline_passed, COMMAND_LINE_SIZE);
+#ifdef CONFIG_NIOS2_CMDLINE_IGNORE_DTB
+	else
+		strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
+#endif
+#endif
+
+	parse_early_param();
+}
+
+static void __init find_limits(unsigned long *min, unsigned long *max_low,
+			       unsigned long *max_high)
+{
+	*max_low = PFN_DOWN(memblock_get_current_limit());
+	*min = PFN_UP(memblock_start_of_DRAM());
+	*max_high = PFN_DOWN(memblock_end_of_DRAM());
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+	console_verbose();
+
+	memory_start = memblock_start_of_DRAM();
+	memory_end = memblock_end_of_DRAM();
+
+	setup_initial_init_mm(_stext, _etext, _edata, _end);
+	init_task.thread.kregs = &fake_regs;
+
+	/* Keep a copy of command line */
+	*cmdline_p = boot_command_line;
+
+	find_limits(&min_low_pfn, &max_low_pfn, &max_pfn);
+	max_mapnr = max_low_pfn;
+
+	memblock_reserve(__pa_symbol(_stext), _end - _stext);
+#ifdef CONFIG_BLK_DEV_INITRD
+	if (initrd_start) {
+		memblock_reserve(virt_to_phys((void *)initrd_start),
+				initrd_end - initrd_start);
+	}
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+	early_init_fdt_reserve_self();
+	early_init_fdt_scan_reserved_mem();
+
+	unflatten_and_copy_device_tree();
+
+	setup_cpuinfo();
+
+	copy_exception_handler(cpuinfo.exception_addr);
+
+	mmu_init();
+
+	copy_fast_tlb_miss_handler(cpuinfo.fast_tlb_miss_exc_addr);
+
+	/*
+	 * Initialize MMU context handling here because data from cpuinfo is
+	 * needed for this.
+	 */
+	mmu_context_init();
+
+	/*
+	 * get kmalloc into gear
+	 */
+	paging_init();
+}
diff --git a/arch/nios2/kernel/signal.c b/arch/nios2/kernel/signal.c
new file mode 100644
index 000000000..a5b93a30c
--- /dev/null
+++ b/arch/nios2/kernel/signal.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright (C) 2013-2014 Altera Corporation
+ * Copyright (C) 2011-2012 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/uaccess.h>
+#include <linux/unistd.h>
+#include <linux/personality.h>
+#include <linux/resume_user_mode.h>
+
+#include <asm/ucontext.h>
+#include <asm/cacheflush.h>
+
+#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
+
+/*
+ * Do a signal return; undo the signal stack.
+ *
+ * Keep the return code on the stack quadword aligned!
+ * That makes the cache flush below easier.
+ */
+
+struct rt_sigframe {
+	struct siginfo info;
+	struct ucontext uc;
+};
+
+static inline int rt_restore_ucontext(struct pt_regs *regs,
+					struct switch_stack *sw,
+					struct ucontext __user *uc, int *pr2)
+{
+	int temp;
+	unsigned long __user *gregs = uc->uc_mcontext.gregs;
+	int err;
+
+	/* Always make any pending restarted system calls return -EINTR */
+	current->restart_block.fn = do_no_restart_syscall;
+
+	err = __get_user(temp, &uc->uc_mcontext.version);
+	if (temp != MCONTEXT_VERSION)
+		goto badframe;
+	/* restore passed registers */
+	err |= __get_user(regs->r1, &gregs[0]);
+	err |= __get_user(regs->r2, &gregs[1]);
+	err |= __get_user(regs->r3, &gregs[2]);
+	err |= __get_user(regs->r4, &gregs[3]);
+	err |= __get_user(regs->r5, &gregs[4]);
+	err |= __get_user(regs->r6, &gregs[5]);
+	err |= __get_user(regs->r7, &gregs[6]);
+	err |= __get_user(regs->r8, &gregs[7]);
+	err |= __get_user(regs->r9, &gregs[8]);
+	err |= __get_user(regs->r10, &gregs[9]);
+	err |= __get_user(regs->r11, &gregs[10]);
+	err |= __get_user(regs->r12, &gregs[11]);
+	err |= __get_user(regs->r13, &gregs[12]);
+	err |= __get_user(regs->r14, &gregs[13]);
+	err |= __get_user(regs->r15, &gregs[14]);
+	err |= __get_user(sw->r16, &gregs[15]);
+	err |= __get_user(sw->r17, &gregs[16]);
+	err |= __get_user(sw->r18, &gregs[17]);
+	err |= __get_user(sw->r19, &gregs[18]);
+	err |= __get_user(sw->r20, &gregs[19]);
+	err |= __get_user(sw->r21, &gregs[20]);
+	err |= __get_user(sw->r22, &gregs[21]);
+	err |= __get_user(sw->r23, &gregs[22]);
+	/* gregs[23] is handled below */
+	err |= __get_user(sw->fp, &gregs[24]);  /* Verify, should this be
+							settable */
+	err |= __get_user(sw->gp, &gregs[25]);  /* Verify, should this be
+							settable */
+
+	err |= __get_user(temp, &gregs[26]);  /* Not really necessary no user
+							settable bits */
+	err |= __get_user(regs->ea, &gregs[27]);
+
+	err |= __get_user(regs->ra, &gregs[23]);
+	err |= __get_user(regs->sp, &gregs[28]);
+
+	regs->orig_r2 = -1;		/* disable syscall checks */
+
+	err |= restore_altstack(&uc->uc_stack);
+	if (err)
+		goto badframe;
+
+	*pr2 = regs->r2;
+	return err;
+
+badframe:
+	return 1;
+}
+
+asmlinkage int do_rt_sigreturn(struct switch_stack *sw)
+{
+	struct pt_regs *regs = (struct pt_regs *)(sw + 1);
+	/* Verify, can we follow the stack back */
+	struct rt_sigframe __user *frame;
+	sigset_t set;
+	int rval;
+
+	frame = (struct rt_sigframe __user *) regs->sp;
+	if (!access_ok(frame, sizeof(*frame)))
+		goto badframe;
+
+	if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+		goto badframe;
+
+	set_current_blocked(&set);
+
+	if (rt_restore_ucontext(regs, sw, &frame->uc, &rval))
+		goto badframe;
+
+	return rval;
+
+badframe:
+	force_sig(SIGSEGV);
+	return 0;
+}
+
+static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs)
+{
+	struct switch_stack *sw = (struct switch_stack *)regs - 1;
+	unsigned long __user *gregs = uc->uc_mcontext.gregs;
+	int err = 0;
+
+	err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
+	err |= __put_user(regs->r1, &gregs[0]);
+	err |= __put_user(regs->r2, &gregs[1]);
+	err |= __put_user(regs->r3, &gregs[2]);
+	err |= __put_user(regs->r4, &gregs[3]);
+	err |= __put_user(regs->r5, &gregs[4]);
+	err |= __put_user(regs->r6, &gregs[5]);
+	err |= __put_user(regs->r7, &gregs[6]);
+	err |= __put_user(regs->r8, &gregs[7]);
+	err |= __put_user(regs->r9, &gregs[8]);
+	err |= __put_user(regs->r10, &gregs[9]);
+	err |= __put_user(regs->r11, &gregs[10]);
+	err |= __put_user(regs->r12, &gregs[11]);
+	err |= __put_user(regs->r13, &gregs[12]);
+	err |= __put_user(regs->r14, &gregs[13]);
+	err |= __put_user(regs->r15, &gregs[14]);
+	err |= __put_user(sw->r16, &gregs[15]);
+	err |= __put_user(sw->r17, &gregs[16]);
+	err |= __put_user(sw->r18, &gregs[17]);
+	err |= __put_user(sw->r19, &gregs[18]);
+	err |= __put_user(sw->r20, &gregs[19]);
+	err |= __put_user(sw->r21, &gregs[20]);
+	err |= __put_user(sw->r22, &gregs[21]);
+	err |= __put_user(sw->r23, &gregs[22]);
+	err |= __put_user(regs->ra, &gregs[23]);
+	err |= __put_user(sw->fp, &gregs[24]);
+	err |= __put_user(sw->gp, &gregs[25]);
+	err |= __put_user(regs->ea, &gregs[27]);
+	err |= __put_user(regs->sp, &gregs[28]);
+	return err;
+}
+
+static inline void __user *get_sigframe(struct ksignal *ksig,
+					struct pt_regs *regs,
+					size_t frame_size)
+{
+	unsigned long usp;
+
+	/* Default to using normal stack.  */
+	usp = regs->sp;
+
+	/* This is the X/Open sanctioned signal stack switching.  */
+	usp = sigsp(usp, ksig);
+
+	/* Verify, is it 32 or 64 bit aligned */
+	return (void __user *)((usp - frame_size) & -8UL);
+}
+
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+			  struct pt_regs *regs)
+{
+	struct rt_sigframe __user *frame;
+	int err = 0;
+
+	frame = get_sigframe(ksig, regs, sizeof(*frame));
+
+	if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+		err |= copy_siginfo_to_user(&frame->info, &ksig->info);
+
+	/* Create the ucontext.  */
+	err |= __put_user(0, &frame->uc.uc_flags);
+	err |= __put_user(0, &frame->uc.uc_link);
+	err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
+	err |= rt_setup_ucontext(&frame->uc, regs);
+	err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+	if (err)
+		goto give_sigsegv;
+
+	/* Set up to return from userspace; jump to fixed address sigreturn
+	   trampoline on kuser page.  */
+	regs->ra = (unsigned long) (0x1044);
+
+	/* Set up registers for signal handler */
+	regs->sp = (unsigned long) frame;
+	regs->r4 = (unsigned long) ksig->sig;
+	regs->r5 = (unsigned long) &frame->info;
+	regs->r6 = (unsigned long) &frame->uc;
+	regs->ea = (unsigned long) ksig->ka.sa.sa_handler;
+	return 0;
+
+give_sigsegv:
+	force_sigsegv(ksig->sig);
+	return -EFAULT;
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+	int ret;
+	sigset_t *oldset = sigmask_to_save();
+
+	/* set up the stack frame */
+	ret = setup_rt_frame(ksig, oldset, regs);
+
+	signal_setup_done(ret, ksig, 0);
+}
+
+static int do_signal(struct pt_regs *regs)
+{
+	unsigned int retval = 0, continue_addr = 0, restart_addr = 0;
+	int restart = 0;
+	struct ksignal ksig;
+
+	current->thread.kregs = regs;
+
+	/*
+	 * If we were from a system call, check for system call restarting...
+	 */
+	if (regs->orig_r2 >= 0 && regs->r1) {
+		continue_addr = regs->ea;
+		restart_addr = continue_addr - 4;
+		retval = regs->r2;
+
+		/*
+		 * Prepare for system call restart. We do this here so that a
+		 * debugger will see the already changed PC.
+		 */
+		switch (retval) {
+		case ERESTART_RESTARTBLOCK:
+			restart = -2;
+			fallthrough;
+		case ERESTARTNOHAND:
+		case ERESTARTSYS:
+		case ERESTARTNOINTR:
+			restart++;
+			regs->r2 = regs->orig_r2;
+			regs->r7 = regs->orig_r7;
+			regs->ea = restart_addr;
+			break;
+		}
+		regs->orig_r2 = -1;
+	}
+
+	if (get_signal(&ksig)) {
+		/* handler */
+		if (unlikely(restart && regs->ea == restart_addr)) {
+			if (retval == ERESTARTNOHAND ||
+			    retval == ERESTART_RESTARTBLOCK ||
+			     (retval == ERESTARTSYS
+				&& !(ksig.ka.sa.sa_flags & SA_RESTART))) {
+				regs->r2 = EINTR;
+				regs->r7 = 1;
+				regs->ea = continue_addr;
+			}
+		}
+		handle_signal(&ksig, regs);
+		return 0;
+	}
+
+	/*
+	 * No handler present
+	 */
+	if (unlikely(restart) && regs->ea == restart_addr) {
+		regs->ea = continue_addr;
+		regs->r2 = __NR_restart_syscall;
+	}
+
+	/*
+	* If there's no signal to deliver, we just put the saved sigmask back.
+	*/
+	restore_saved_sigmask();
+
+	return restart;
+}
+
+asmlinkage int do_notify_resume(struct pt_regs *regs)
+{
+	/*
+	 * We want the common case to go fast, which is why we may in certain
+	 * cases get here from kernel mode. Just return without doing anything
+	 * if so.
+	 */
+	if (!user_mode(regs))
+		return 0;
+
+	if (test_thread_flag(TIF_SIGPENDING) ||
+	    test_thread_flag(TIF_NOTIFY_SIGNAL)) {
+		int restart = do_signal(regs);
+
+		if (unlikely(restart)) {
+			/*
+			 * Restart without handlers.
+			 * Deal with it without leaving
+			 * the kernel space.
+			 */
+			return restart;
+		}
+	} else if (test_thread_flag(TIF_NOTIFY_RESUME))
+		resume_user_mode_work(regs);
+
+	return 0;
+}
diff --git a/arch/nios2/kernel/sys_nios2.c b/arch/nios2/kernel/sys_nios2.c
new file mode 100644
index 000000000..b1ca85699
--- /dev/null
+++ b/arch/nios2/kernel/sys_nios2.c
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2011-2012 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+
+#include <asm/cacheflush.h>
+#include <asm/traps.h>
+
+/* sys_cacheflush -- flush the processor cache. */
+asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len,
+				unsigned int op)
+{
+	struct vm_area_struct *vma;
+	struct mm_struct *mm = current->mm;
+
+	if (len == 0)
+		return 0;
+
+	/* We only support op 0 now, return error if op is non-zero.*/
+	if (op)
+		return -EINVAL;
+
+	/* Check for overflow */
+	if (addr + len < addr)
+		return -EFAULT;
+
+	if (mmap_read_lock_killable(mm))
+		return -EINTR;
+
+	/*
+	 * Verify that the specified address region actually belongs
+	 * to this process.
+	 */
+	vma = find_vma(mm, addr);
+	if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end) {
+		mmap_read_unlock(mm);
+		return -EFAULT;
+	}
+
+	flush_cache_range(vma, addr, addr + len);
+
+	mmap_read_unlock(mm);
+	return 0;
+}
+
+asmlinkage int sys_getpagesize(void)
+{
+	return PAGE_SIZE;
+}
diff --git a/arch/nios2/kernel/syscall_table.c b/arch/nios2/kernel/syscall_table.c
new file mode 100644
index 000000000..c2875a6dd
--- /dev/null
+++ b/arch/nios2/kernel/syscall_table.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright Altera Corporation (C) 2013. All rights reserved
+ */
+
+#include <linux/syscalls.h>
+#include <linux/signal.h>
+#include <linux/unistd.h>
+
+#include <asm/syscalls.h>
+
+#undef __SYSCALL
+#define __SYSCALL(nr, call) [nr] = (call),
+
+void *sys_call_table[__NR_syscalls] = {
+	[0 ... __NR_syscalls-1] = sys_ni_syscall,
+#include <asm/unistd.h>
+};
diff --git a/arch/nios2/kernel/time.c b/arch/nios2/kernel/time.c
new file mode 100644
index 000000000..54467d008
--- /dev/null
+++ b/arch/nios2/kernel/time.c
@@ -0,0 +1,359 @@
+/*
+ * Copyright (C) 2013-2014 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#define ALTR_TIMER_COMPATIBLE		"altr,timer-1.0"
+
+#define ALTERA_TIMER_STATUS_REG	0
+#define ALTERA_TIMER_CONTROL_REG	4
+#define ALTERA_TIMER_PERIODL_REG	8
+#define ALTERA_TIMER_PERIODH_REG	12
+#define ALTERA_TIMER_SNAPL_REG		16
+#define ALTERA_TIMER_SNAPH_REG		20
+
+#define ALTERA_TIMER_CONTROL_ITO_MSK	(0x1)
+#define ALTERA_TIMER_CONTROL_CONT_MSK	(0x2)
+#define ALTERA_TIMER_CONTROL_START_MSK	(0x4)
+#define ALTERA_TIMER_CONTROL_STOP_MSK	(0x8)
+
+struct nios2_timer {
+	void __iomem *base;
+	unsigned long freq;
+};
+
+struct nios2_clockevent_dev {
+	struct nios2_timer timer;
+	struct clock_event_device ced;
+};
+
+struct nios2_clocksource {
+	struct nios2_timer timer;
+	struct clocksource cs;
+};
+
+static inline struct nios2_clockevent_dev *
+	to_nios2_clkevent(struct clock_event_device *evt)
+{
+	return container_of(evt, struct nios2_clockevent_dev, ced);
+}
+
+static inline struct nios2_clocksource *
+	to_nios2_clksource(struct clocksource *cs)
+{
+	return container_of(cs, struct nios2_clocksource, cs);
+}
+
+static u16 timer_readw(struct nios2_timer *timer, u32 offs)
+{
+	return readw(timer->base + offs);
+}
+
+static void timer_writew(struct nios2_timer *timer, u16 val, u32 offs)
+{
+	writew(val, timer->base + offs);
+}
+
+static inline unsigned long read_timersnapshot(struct nios2_timer *timer)
+{
+	unsigned long count;
+
+	timer_writew(timer, 0, ALTERA_TIMER_SNAPL_REG);
+	count = timer_readw(timer, ALTERA_TIMER_SNAPH_REG) << 16 |
+		timer_readw(timer, ALTERA_TIMER_SNAPL_REG);
+
+	return count;
+}
+
+static u64 nios2_timer_read(struct clocksource *cs)
+{
+	struct nios2_clocksource *nios2_cs = to_nios2_clksource(cs);
+	unsigned long flags;
+	u32 count;
+
+	local_irq_save(flags);
+	count = read_timersnapshot(&nios2_cs->timer);
+	local_irq_restore(flags);
+
+	/* Counter is counting down */
+	return ~count;
+}
+
+static struct nios2_clocksource nios2_cs = {
+	.cs = {
+		.name	= "nios2-clksrc",
+		.rating	= 250,
+		.read	= nios2_timer_read,
+		.mask	= CLOCKSOURCE_MASK(32),
+		.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+	},
+};
+
+cycles_t get_cycles(void)
+{
+	/* Only read timer if it has been initialized */
+	if (nios2_cs.timer.base)
+		return nios2_timer_read(&nios2_cs.cs);
+	return 0;
+}
+EXPORT_SYMBOL(get_cycles);
+
+static void nios2_timer_start(struct nios2_timer *timer)
+{
+	u16 ctrl;
+
+	ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG);
+	ctrl |= ALTERA_TIMER_CONTROL_START_MSK;
+	timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG);
+}
+
+static void nios2_timer_stop(struct nios2_timer *timer)
+{
+	u16 ctrl;
+
+	ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG);
+	ctrl |= ALTERA_TIMER_CONTROL_STOP_MSK;
+	timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG);
+}
+
+static void nios2_timer_config(struct nios2_timer *timer, unsigned long period,
+			       bool periodic)
+{
+	u16 ctrl;
+
+	/* The timer's actual period is one cycle greater than the value
+	 * stored in the period register. */
+	 period--;
+
+	ctrl = timer_readw(timer, ALTERA_TIMER_CONTROL_REG);
+	/* stop counter */
+	timer_writew(timer, ctrl | ALTERA_TIMER_CONTROL_STOP_MSK,
+		ALTERA_TIMER_CONTROL_REG);
+
+	/* write new count */
+	timer_writew(timer, period, ALTERA_TIMER_PERIODL_REG);
+	timer_writew(timer, period >> 16, ALTERA_TIMER_PERIODH_REG);
+
+	ctrl |= ALTERA_TIMER_CONTROL_START_MSK | ALTERA_TIMER_CONTROL_ITO_MSK;
+	if (periodic)
+		ctrl |= ALTERA_TIMER_CONTROL_CONT_MSK;
+	else
+		ctrl &= ~ALTERA_TIMER_CONTROL_CONT_MSK;
+	timer_writew(timer, ctrl, ALTERA_TIMER_CONTROL_REG);
+}
+
+static int nios2_timer_set_next_event(unsigned long delta,
+	struct clock_event_device *evt)
+{
+	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
+
+	nios2_timer_config(&nios2_ced->timer, delta, false);
+
+	return 0;
+}
+
+static int nios2_timer_shutdown(struct clock_event_device *evt)
+{
+	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
+	struct nios2_timer *timer = &nios2_ced->timer;
+
+	nios2_timer_stop(timer);
+	return 0;
+}
+
+static int nios2_timer_set_periodic(struct clock_event_device *evt)
+{
+	unsigned long period;
+	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
+	struct nios2_timer *timer = &nios2_ced->timer;
+
+	period = DIV_ROUND_UP(timer->freq, HZ);
+	nios2_timer_config(timer, period, true);
+	return 0;
+}
+
+static int nios2_timer_resume(struct clock_event_device *evt)
+{
+	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
+	struct nios2_timer *timer = &nios2_ced->timer;
+
+	nios2_timer_start(timer);
+	return 0;
+}
+
+irqreturn_t timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *) dev_id;
+	struct nios2_clockevent_dev *nios2_ced = to_nios2_clkevent(evt);
+
+	/* Clear the interrupt condition */
+	timer_writew(&nios2_ced->timer, 0, ALTERA_TIMER_STATUS_REG);
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init nios2_timer_get_base_and_freq(struct device_node *np,
+				void __iomem **base, u32 *freq)
+{
+	*base = of_iomap(np, 0);
+	if (!*base) {
+		pr_crit("Unable to map reg for %pOFn\n", np);
+		return -ENXIO;
+	}
+
+	if (of_property_read_u32(np, "clock-frequency", freq)) {
+		pr_crit("Unable to get %pOFn clock frequency\n", np);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static struct nios2_clockevent_dev nios2_ce = {
+	.ced = {
+		.name = "nios2-clkevent",
+		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+		.rating = 250,
+		.shift = 32,
+		.set_next_event = nios2_timer_set_next_event,
+		.set_state_shutdown = nios2_timer_shutdown,
+		.set_state_periodic = nios2_timer_set_periodic,
+		.set_state_oneshot = nios2_timer_shutdown,
+		.tick_resume = nios2_timer_resume,
+	},
+};
+
+static __init int nios2_clockevent_init(struct device_node *timer)
+{
+	void __iomem *iobase;
+	u32 freq;
+	int irq, ret;
+
+	ret = nios2_timer_get_base_and_freq(timer, &iobase, &freq);
+	if (ret)
+		return ret;
+
+	irq = irq_of_parse_and_map(timer, 0);
+	if (!irq) {
+		pr_crit("Unable to parse timer irq\n");
+		return -EINVAL;
+	}
+
+	nios2_ce.timer.base = iobase;
+	nios2_ce.timer.freq = freq;
+
+	nios2_ce.ced.cpumask = cpumask_of(0);
+	nios2_ce.ced.irq = irq;
+
+	nios2_timer_stop(&nios2_ce.timer);
+	/* clear pending interrupt */
+	timer_writew(&nios2_ce.timer, 0, ALTERA_TIMER_STATUS_REG);
+
+	ret = request_irq(irq, timer_interrupt, IRQF_TIMER, timer->name,
+			  &nios2_ce.ced);
+	if (ret) {
+		pr_crit("Unable to setup timer irq\n");
+		return ret;
+	}
+
+	clockevents_config_and_register(&nios2_ce.ced, freq, 1, ULONG_MAX);
+
+	return 0;
+}
+
+static __init int nios2_clocksource_init(struct device_node *timer)
+{
+	unsigned int ctrl;
+	void __iomem *iobase;
+	u32 freq;
+	int ret;
+
+	ret = nios2_timer_get_base_and_freq(timer, &iobase, &freq);
+	if (ret)
+		return ret;
+
+	nios2_cs.timer.base = iobase;
+	nios2_cs.timer.freq = freq;
+
+	ret = clocksource_register_hz(&nios2_cs.cs, freq);
+	if (ret)
+		return ret;
+
+	timer_writew(&nios2_cs.timer, USHRT_MAX, ALTERA_TIMER_PERIODL_REG);
+	timer_writew(&nios2_cs.timer, USHRT_MAX, ALTERA_TIMER_PERIODH_REG);
+
+	/* interrupt disable + continuous + start */
+	ctrl = ALTERA_TIMER_CONTROL_CONT_MSK | ALTERA_TIMER_CONTROL_START_MSK;
+	timer_writew(&nios2_cs.timer, ctrl, ALTERA_TIMER_CONTROL_REG);
+
+	/* Calibrate the delay loop directly */
+	lpj_fine = freq / HZ;
+
+	return 0;
+}
+
+/*
+ * The first timer instance will use as a clockevent. If there are two or
+ * more instances, the second one gets used as clocksource and all
+ * others are unused.
+*/
+static int __init nios2_time_init(struct device_node *timer)
+{
+	static int num_called;
+	int ret;
+
+	switch (num_called) {
+	case 0:
+		ret = nios2_clockevent_init(timer);
+		break;
+	case 1:
+		ret = nios2_clocksource_init(timer);
+		break;
+	default:
+		ret = 0;
+		break;
+	}
+
+	num_called++;
+
+	return ret;
+}
+
+void read_persistent_clock64(struct timespec64 *ts)
+{
+	ts->tv_sec = mktime64(2007, 1, 1, 0, 0, 0);
+	ts->tv_nsec = 0;
+}
+
+void __init time_init(void)
+{
+	struct device_node *np;
+	int count = 0;
+
+	for_each_compatible_node(np, NULL,  ALTR_TIMER_COMPATIBLE)
+		count++;
+
+	if (count < 2)
+		panic("%d timer is found, it needs 2 timers in system\n", count);
+
+	timer_probe();
+}
+
+TIMER_OF_DECLARE(nios2_timer, ALTR_TIMER_COMPATIBLE, nios2_time_init);
diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c
new file mode 100644
index 000000000..85ac49d64
--- /dev/null
+++ b/arch/nios2/kernel/traps.c
@@ -0,0 +1,196 @@
+/*
+ * Hardware exception handling
+ *
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ * Copyright (C) 2001 Vic Phillips
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License.  See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/ptrace.h>
+
+#include <asm/traps.h>
+#include <asm/sections.h>
+#include <linux/uaccess.h>
+
+static DEFINE_SPINLOCK(die_lock);
+
+static void _send_sig(int signo, int code, unsigned long addr)
+{
+	force_sig_fault(signo, code, (void __user *) addr);
+}
+
+void die(const char *str, struct pt_regs *regs, long err)
+{
+	console_verbose();
+	spin_lock_irq(&die_lock);
+	pr_warn("Oops: %s, sig: %ld\n", str, err);
+	show_regs(regs);
+	spin_unlock_irq(&die_lock);
+	/*
+	 * make_task_dead() should take care of panic'ing from an interrupt
+	 * context so we don't handle it here
+	 */
+	make_task_dead(err);
+}
+
+void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr)
+{
+	if (!user_mode(regs))
+		die("Exception in kernel mode", regs, signo);
+
+	_send_sig(signo, code, addr);
+}
+
+/*
+ * The show_stack() is external API which we do not use ourselves.
+ */
+
+int kstack_depth_to_print = 48;
+
+void show_stack(struct task_struct *task, unsigned long *stack,
+		const char *loglvl)
+{
+	unsigned long *endstack, addr;
+	int i;
+
+	if (!stack) {
+		if (task)
+			stack = (unsigned long *)task->thread.ksp;
+		else
+			stack = (unsigned long *)&stack;
+	}
+
+	addr = (unsigned long) stack;
+	endstack = (unsigned long *) PAGE_ALIGN(addr);
+
+	printk("%sStack from %08lx:", loglvl, (unsigned long)stack);
+	for (i = 0; i < kstack_depth_to_print; i++) {
+		if (stack + 1 > endstack)
+			break;
+		if (i % 8 == 0)
+			printk("%s\n       ", loglvl);
+		printk("%s %08lx", loglvl, *stack++);
+	}
+
+	printk("%s\nCall Trace:", loglvl);
+	i = 0;
+	while (stack + 1 <= endstack) {
+		addr = *stack++;
+		/*
+		 * If the address is either in the text segment of the
+		 * kernel, or in the region which contains vmalloc'ed
+		 * memory, it *may* be the address of a calling
+		 * routine; if so, print it so that someone tracing
+		 * down the cause of the crash will be able to figure
+		 * out the call path that was taken.
+		 */
+		if (((addr >= (unsigned long) _stext) &&
+		     (addr <= (unsigned long) _etext))) {
+			if (i % 4 == 0)
+				pr_emerg("\n       ");
+			printk("%s [<%08lx>]", loglvl, addr);
+			i++;
+		}
+	}
+	printk("%s\n", loglvl);
+}
+
+/* Breakpoint handler */
+asmlinkage void breakpoint_c(struct pt_regs *fp)
+{
+	/*
+	 * The breakpoint entry code has moved the PC on by 4 bytes, so we must
+	 * move it back. This could be done on the host but we do it here
+	 * because monitor.S of JTAG gdbserver does it too.
+	 */
+	fp->ea -= 4;
+	_exception(SIGTRAP, fp, TRAP_BRKPT, fp->ea);
+}
+
+#ifndef CONFIG_NIOS2_ALIGNMENT_TRAP
+/* Alignment exception handler */
+asmlinkage void handle_unaligned_c(struct pt_regs *fp, int cause)
+{
+	unsigned long addr = RDCTL(CTL_BADADDR);
+
+	cause >>= 2;
+	fp->ea -= 4;
+
+	if (fixup_exception(fp))
+		return;
+
+	if (!user_mode(fp)) {
+		pr_alert("Unaligned access from kernel mode, this might be a hardware\n");
+		pr_alert("problem, dump registers and restart the instruction\n");
+		pr_alert("  BADADDR 0x%08lx\n", addr);
+		pr_alert("  cause   %d\n", cause);
+		pr_alert("  op-code 0x%08lx\n", *(unsigned long *)(fp->ea));
+		show_regs(fp);
+		return;
+	}
+
+	_exception(SIGBUS, fp, BUS_ADRALN, addr);
+}
+#endif /* CONFIG_NIOS2_ALIGNMENT_TRAP */
+
+/* Illegal instruction handler */
+asmlinkage void handle_illegal_c(struct pt_regs *fp)
+{
+	fp->ea -= 4;
+	_exception(SIGILL, fp, ILL_ILLOPC, fp->ea);
+}
+
+/* Supervisor instruction handler */
+asmlinkage void handle_supervisor_instr(struct pt_regs *fp)
+{
+	fp->ea -= 4;
+	_exception(SIGILL, fp, ILL_PRVOPC, fp->ea);
+}
+
+/* Division error handler */
+asmlinkage void handle_diverror_c(struct pt_regs *fp)
+{
+	fp->ea -= 4;
+	_exception(SIGFPE, fp, FPE_INTDIV, fp->ea);
+}
+
+/* Unhandled exception handler */
+asmlinkage void unhandled_exception(struct pt_regs *regs, int cause)
+{
+	unsigned long addr = RDCTL(CTL_BADADDR);
+
+	cause /= 4;
+
+	pr_emerg("Unhandled exception #%d in %s mode (badaddr=0x%08lx)\n",
+			cause, user_mode(regs) ? "user" : "kernel", addr);
+
+	regs->ea -= 4;
+	show_regs(regs);
+
+	pr_emerg("opcode: 0x%08lx\n", *(unsigned long *)(regs->ea));
+}
+
+asmlinkage void handle_trap_1_c(struct pt_regs *fp)
+{
+	_send_sig(SIGUSR1, 0, fp->ea);
+}
+
+asmlinkage void handle_trap_2_c(struct pt_regs *fp)
+{
+	_send_sig(SIGUSR2, 0, fp->ea);
+}
+
+asmlinkage void handle_trap_3_c(struct pt_regs *fp)
+{
+	_send_sig(SIGILL, ILL_ILLTRP, fp->ea);
+}
diff --git a/arch/nios2/kernel/vmlinux.lds.S b/arch/nios2/kernel/vmlinux.lds.S
new file mode 100644
index 000000000..126e11474
--- /dev/null
+++ b/arch/nios2/kernel/vmlinux.lds.S
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
+ */
+#include <asm/page.h>
+#include <asm-generic/vmlinux.lds.h>
+#include <asm/cache.h>
+#include <asm/thread_info.h>
+
+OUTPUT_FORMAT("elf32-littlenios2", "elf32-littlenios2", "elf32-littlenios2")
+
+OUTPUT_ARCH(nios)
+ENTRY(_start)	/* Defined in head.S */
+
+jiffies = jiffies_64;
+
+SECTIONS
+{
+	. = CONFIG_NIOS2_MEM_BASE | CONFIG_NIOS2_KERNEL_REGION_BASE;
+
+	_text = .;
+	_stext = .;
+	HEAD_TEXT_SECTION
+	.text : {
+		TEXT_TEXT
+		SCHED_TEXT
+		CPUIDLE_TEXT
+		LOCK_TEXT
+		IRQENTRY_TEXT
+		SOFTIRQENTRY_TEXT
+		KPROBES_TEXT
+	} =0
+	_etext = .;
+
+	.got : {
+		*(.got.plt)
+		*(.igot.plt)
+		*(.got)
+		*(.igot)
+	}
+
+	EXCEPTION_TABLE(L1_CACHE_BYTES)
+
+	. = ALIGN(PAGE_SIZE);
+	__init_begin = .;
+	INIT_TEXT_SECTION(PAGE_SIZE)
+	INIT_DATA_SECTION(PAGE_SIZE)
+	PERCPU_SECTION(L1_CACHE_BYTES)
+	__init_end = .;
+
+	_sdata = .;
+	RO_DATA(PAGE_SIZE)
+	RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+	_edata = .;
+
+	BSS_SECTION(0, 0, 0)
+	_end = .;
+
+	STABS_DEBUG
+	DWARF_DEBUG
+	ELF_DETAILS
+
+	DISCARDS
+}
diff --git a/arch/nios2/lib/Makefile b/arch/nios2/lib/Makefile
new file mode 100644
index 000000000..9d5bf1df5
--- /dev/null
+++ b/arch/nios2/lib/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for Nios2-specific library files.
+#
+
+lib-y += delay.o
+lib-y += memcpy.o
+lib-y += memmove.o
+lib-y += memset.o
diff --git a/arch/nios2/lib/delay.c b/arch/nios2/lib/delay.c
new file mode 100644
index 000000000..f1e39c7f7
--- /dev/null
+++ b/arch/nios2/lib/delay.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright Altera Corporation (C) 2014. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <asm/delay.h>
+#include <asm/param.h>
+#include <asm/processor.h>
+#include <asm/timex.h>
+
+void __delay(unsigned long cycles)
+{
+	cycles_t start = get_cycles();
+
+	while ((get_cycles() - start) < cycles)
+		cpu_relax();
+}
+EXPORT_SYMBOL(__delay);
+
+void __const_udelay(unsigned long xloops)
+{
+	u64 loops;
+
+	loops = (u64)xloops * loops_per_jiffy * HZ;
+
+	__delay(loops >> 32);
+}
+EXPORT_SYMBOL(__const_udelay);
+
+void __udelay(unsigned long usecs)
+{
+	__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
+}
+EXPORT_SYMBOL(__udelay);
+
+void __ndelay(unsigned long nsecs)
+{
+	__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
+}
+EXPORT_SYMBOL(__ndelay);
diff --git a/arch/nios2/lib/memcpy.c b/arch/nios2/lib/memcpy.c
new file mode 100644
index 000000000..1715f5d28
--- /dev/null
+++ b/arch/nios2/lib/memcpy.c
@@ -0,0 +1,202 @@
+/* Extracted from GLIBC memcpy.c and memcopy.h, which is:
+   Copyright (C) 1991, 1992, 1993, 1997, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Torbjorn Granlund (tege@sics.se).
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <linux/types.h>
+
+/* Type to use for aligned memory operations.
+   This should normally be the biggest type supported by a single load
+   and store.  */
+#define	op_t	unsigned long int
+#define OPSIZ	(sizeof(op_t))
+
+/* Optimal type for storing bytes in registers.  */
+#define	reg_char	char
+
+#define MERGE(w0, sh_1, w1, sh_2) (((w0) >> (sh_1)) | ((w1) << (sh_2)))
+
+/* Copy exactly NBYTES bytes from SRC_BP to DST_BP,
+   without any assumptions about alignment of the pointers.  */
+#define BYTE_COPY_FWD(dst_bp, src_bp, nbytes)				\
+do {									\
+	size_t __nbytes = (nbytes);					\
+	while (__nbytes > 0) {						\
+		unsigned char __x = ((unsigned char *) src_bp)[0];	\
+		src_bp += 1;						\
+		__nbytes -= 1;						\
+		((unsigned char *) dst_bp)[0] = __x;			\
+		dst_bp += 1;						\
+	}								\
+} while (0)
+
+/* Copy *up to* NBYTES bytes from SRC_BP to DST_BP, with
+   the assumption that DST_BP is aligned on an OPSIZ multiple.  If
+   not all bytes could be easily copied, store remaining number of bytes
+   in NBYTES_LEFT, otherwise store 0.  */
+/* extern void _wordcopy_fwd_aligned __P ((long int, long int, size_t)); */
+/* extern void _wordcopy_fwd_dest_aligned __P ((long int, long int, size_t)); */
+#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes)		\
+do {									\
+	if (src_bp % OPSIZ == 0)					\
+		_wordcopy_fwd_aligned(dst_bp, src_bp, (nbytes) / OPSIZ);\
+	else								\
+		_wordcopy_fwd_dest_aligned(dst_bp, src_bp, (nbytes) / OPSIZ);\
+	src_bp += (nbytes) & -OPSIZ;					\
+	dst_bp += (nbytes) & -OPSIZ;					\
+	(nbytes_left) = (nbytes) % OPSIZ;				\
+} while (0)
+
+
+/* Threshold value for when to enter the unrolled loops.  */
+#define	OP_T_THRES	16
+
+/* _wordcopy_fwd_aligned -- Copy block beginning at SRCP to
+   block beginning at DSTP with LEN `op_t' words (not LEN bytes!).
+   Both SRCP and DSTP should be aligned for memory operations on `op_t's.  */
+/* stream-lined (read x8 + write x8) */
+static void _wordcopy_fwd_aligned(long int dstp, long int srcp, size_t len)
+{
+	while (len > 7) {
+		register op_t a0, a1, a2, a3, a4, a5, a6, a7;
+
+		a0 = ((op_t *) srcp)[0];
+		a1 = ((op_t *) srcp)[1];
+		a2 = ((op_t *) srcp)[2];
+		a3 = ((op_t *) srcp)[3];
+		a4 = ((op_t *) srcp)[4];
+		a5 = ((op_t *) srcp)[5];
+		a6 = ((op_t *) srcp)[6];
+		a7 = ((op_t *) srcp)[7];
+		((op_t *) dstp)[0] = a0;
+		((op_t *) dstp)[1] = a1;
+		((op_t *) dstp)[2] = a2;
+		((op_t *) dstp)[3] = a3;
+		((op_t *) dstp)[4] = a4;
+		((op_t *) dstp)[5] = a5;
+		((op_t *) dstp)[6] = a6;
+		((op_t *) dstp)[7] = a7;
+
+		srcp += 8 * OPSIZ;
+		dstp += 8 * OPSIZ;
+		len -= 8;
+	}
+	while (len > 0) {
+		*(op_t *)dstp = *(op_t *)srcp;
+
+		srcp += OPSIZ;
+		dstp += OPSIZ;
+		len -= 1;
+	}
+}
+
+/* _wordcopy_fwd_dest_aligned -- Copy block beginning at SRCP to
+   block beginning at DSTP with LEN `op_t' words (not LEN bytes!).
+   DSTP should be aligned for memory operations on `op_t's, but SRCP must
+   *not* be aligned.  */
+/* stream-lined (read x4 + write x4) */
+static void _wordcopy_fwd_dest_aligned(long int dstp, long int srcp,
+					size_t len)
+{
+	op_t ap;
+	int sh_1, sh_2;
+
+	/* Calculate how to shift a word read at the memory operation
+	aligned srcp to make it aligned for copy. */
+
+	sh_1 = 8 * (srcp % OPSIZ);
+	sh_2 = 8 * OPSIZ - sh_1;
+
+	/* Make SRCP aligned by rounding it down to the beginning of the `op_t'
+	it points in the middle of. */
+	srcp &= -OPSIZ;
+	ap = ((op_t *) srcp)[0];
+	srcp += OPSIZ;
+
+	while (len > 3) {
+		op_t a0, a1, a2, a3;
+
+		a0 = ((op_t *) srcp)[0];
+		a1 = ((op_t *) srcp)[1];
+		a2 = ((op_t *) srcp)[2];
+		a3 = ((op_t *) srcp)[3];
+		((op_t *) dstp)[0] = MERGE(ap, sh_1, a0, sh_2);
+		((op_t *) dstp)[1] = MERGE(a0, sh_1, a1, sh_2);
+		((op_t *) dstp)[2] = MERGE(a1, sh_1, a2, sh_2);
+		((op_t *) dstp)[3] = MERGE(a2, sh_1, a3, sh_2);
+
+		ap = a3;
+		srcp += 4 * OPSIZ;
+		dstp += 4 * OPSIZ;
+		len -= 4;
+	}
+	while (len > 0) {
+		register op_t a0;
+
+		a0 = ((op_t *) srcp)[0];
+		((op_t *) dstp)[0] = MERGE(ap, sh_1, a0, sh_2);
+
+		ap = a0;
+		srcp += OPSIZ;
+		dstp += OPSIZ;
+		len -= 1;
+	}
+}
+
+void *memcpy(void *dstpp, const void *srcpp, size_t len)
+{
+	unsigned long int dstp = (long int) dstpp;
+	unsigned long int srcp = (long int) srcpp;
+
+	/* Copy from the beginning to the end.  */
+
+	/* If there not too few bytes to copy, use word copy.  */
+	if (len >= OP_T_THRES) {
+		/* Copy just a few bytes to make DSTP aligned.  */
+		len -= (-dstp) % OPSIZ;
+		BYTE_COPY_FWD(dstp, srcp, (-dstp) % OPSIZ);
+
+		/* Copy whole pages from SRCP to DSTP by virtual address
+		   manipulation, as much as possible.  */
+
+		/* PAGE_COPY_FWD_MAYBE (dstp, srcp, len, len); */
+
+		/* Copy from SRCP to DSTP taking advantage of the known
+		   alignment of DSTP. Number of bytes remaining is put in the
+		   third argument, i.e. in LEN.  This number may vary from
+		   machine to machine. */
+
+		WORD_COPY_FWD(dstp, srcp, len, len);
+
+		/* Fall out and copy the tail. */
+	}
+
+	/* There are just a few bytes to copy.  Use byte memory operations. */
+	BYTE_COPY_FWD(dstp, srcp, len);
+
+	return dstpp;
+}
+
+void *memcpyb(void *dstpp, const void *srcpp, unsigned len)
+{
+	unsigned long int dstp = (long int) dstpp;
+	unsigned long int srcp = (long int) srcpp;
+
+	BYTE_COPY_FWD(dstp, srcp, len);
+
+	return dstpp;
+}
diff --git a/arch/nios2/lib/memmove.c b/arch/nios2/lib/memmove.c
new file mode 100644
index 000000000..866c021f2
--- /dev/null
+++ b/arch/nios2/lib/memmove.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+
+void *memmove(void *d, const void *s, size_t count)
+{
+	unsigned long dst, src;
+
+	if (!count)
+		return d;
+
+	if (d < s) {
+		dst = (unsigned long) d;
+		src = (unsigned long) s;
+
+		if ((count < 8) || ((dst ^ src) & 3))
+			goto restup;
+
+		if (dst & 1) {
+			*(char *)dst++ = *(char *)src++;
+			count--;
+		}
+		if (dst & 2) {
+			*(short *)dst = *(short *)src;
+			src += 2;
+			dst += 2;
+			count -= 2;
+		}
+		while (count > 3) {
+			*(long *)dst = *(long *)src;
+			src += 4;
+			dst += 4;
+			count -= 4;
+		}
+restup:
+		while (count--)
+			*(char *)dst++ = *(char *)src++;
+	} else {
+		dst = (unsigned long) d + count;
+		src = (unsigned long) s + count;
+
+		if ((count < 8) || ((dst ^ src) & 3))
+			goto restdown;
+
+		if (dst & 1) {
+			src--;
+			dst--;
+			count--;
+			*(char *)dst = *(char *)src;
+		}
+		if (dst & 2) {
+			src -= 2;
+			dst -= 2;
+			count -= 2;
+			*(short *)dst = *(short *)src;
+		}
+		while (count > 3) {
+			src -= 4;
+			dst -= 4;
+			count -= 4;
+			*(long *)dst = *(long *)src;
+		}
+restdown:
+		while (count--) {
+			src--;
+			dst--;
+			*(char *)dst = *(char *)src;
+		}
+	}
+
+	return d;
+}
diff --git a/arch/nios2/lib/memset.c b/arch/nios2/lib/memset.c
new file mode 100644
index 000000000..2fcefe720
--- /dev/null
+++ b/arch/nios2/lib/memset.c
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+
+void *memset(void *s, int c, size_t count)
+{
+	int destptr, charcnt, dwordcnt, fill8reg, wrkrega;
+
+	if (!count)
+		return s;
+
+	c &= 0xFF;
+
+	if (count <= 8) {
+		char *xs = (char *) s;
+
+		while (count--)
+			*xs++ = c;
+		return s;
+	}
+
+	__asm__ __volatile__ (
+		/* fill8 %3, %5 (c & 0xff) */
+		"	slli	%4, %5, 8\n"
+		"	or	%4, %4, %5\n"
+		"	slli    %3, %4, 16\n"
+		"	or	%3, %3, %4\n"
+		/* Word-align %0 (s) if necessary */
+		"	andi	%4, %0, 0x01\n"
+		"	beq	%4, zero, 1f\n"
+		"	addi	%1, %1, -1\n"
+		"	stb	%3, 0(%0)\n"
+		"	addi	%0, %0, 1\n"
+		"1:	mov	%2, %1\n"
+		/* Dword-align %0 (s) if necessary */
+		"	andi	%4, %0, 0x02\n"
+		"	beq	%4, zero, 2f\n"
+		"	addi	%1, %1, -2\n"
+		"	sth	%3, 0(%0)\n"
+		"	addi	%0, %0, 2\n"
+		"	mov	%2, %1\n"
+		/* %1 and %2 are how many more bytes to set */
+		"2:	srli	%2, %2, 2\n"
+		/* %2 is how many dwords to set */
+		"3:	stw	%3, 0(%0)\n"
+		"	addi	%0, %0, 4\n"
+		"	addi    %2, %2, -1\n"
+		"	bne	%2, zero, 3b\n"
+		/* store residual word and/or byte if necessary */
+		"	andi	%4, %1, 0x02\n"
+		"	beq	%4, zero, 4f\n"
+		"	sth	%3, 0(%0)\n"
+		"	addi	%0, %0, 2\n"
+		/* store residual byte if necessary */
+		"4:	andi	%4, %1, 0x01\n"
+		"	beq	%4, zero, 5f\n"
+		"	stb	%3, 0(%0)\n"
+		"5:\n"
+		: "=r" (destptr),	/* %0  Output */
+		  "=r" (charcnt),	/* %1  Output */
+		  "=r" (dwordcnt),	/* %2  Output */
+		  "=r" (fill8reg),	/* %3  Output */
+		  "=&r" (wrkrega)	/* %4  Output only */
+		: "r" (c),		/* %5  Input */
+		  "0" (s),		/* %0  Input/Output */
+		  "1" (count)		/* %1  Input/Output */
+		: "memory"		/* clobbered */
+	);
+
+	return s;
+}
diff --git a/arch/nios2/mm/Makefile b/arch/nios2/mm/Makefile
new file mode 100644
index 000000000..9d37fafd1
--- /dev/null
+++ b/arch/nios2/mm/Makefile
@@ -0,0 +1,15 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the Nios2-specific parts of the memory manager.
+#
+
+obj-y	+= cacheflush.o
+obj-y	+= dma-mapping.o
+obj-y	+= extable.o
+obj-y	+= fault.o
+obj-y	+= init.o
+obj-y	+= ioremap.o
+obj-y	+= mmu_context.o
+obj-y	+= pgtable.o
+obj-y	+= tlb.o
+obj-y	+= uaccess.o
diff --git a/arch/nios2/mm/cacheflush.c b/arch/nios2/mm/cacheflush.c
new file mode 100644
index 000000000..6aa9257c3
--- /dev/null
+++ b/arch/nios2/mm/cacheflush.c
@@ -0,0 +1,273 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009, Wind River Systems Inc
+ * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cpuinfo.h>
+
+static void __flush_dcache(unsigned long start, unsigned long end)
+{
+	unsigned long addr;
+
+	start &= ~(cpuinfo.dcache_line_size - 1);
+	end += (cpuinfo.dcache_line_size - 1);
+	end &= ~(cpuinfo.dcache_line_size - 1);
+
+	if (end > start + cpuinfo.dcache_size)
+		end = start + cpuinfo.dcache_size;
+
+	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
+		__asm__ __volatile__ ("   flushd 0(%0)\n"
+					: /* Outputs */
+					: /* Inputs  */ "r"(addr)
+					/* : No clobber */);
+	}
+}
+
+static void __invalidate_dcache(unsigned long start, unsigned long end)
+{
+	unsigned long addr;
+
+	start &= ~(cpuinfo.dcache_line_size - 1);
+	end += (cpuinfo.dcache_line_size - 1);
+	end &= ~(cpuinfo.dcache_line_size - 1);
+
+	for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
+		__asm__ __volatile__ ("   initda 0(%0)\n"
+					: /* Outputs */
+					: /* Inputs  */ "r"(addr)
+					/* : No clobber */);
+	}
+}
+
+static void __flush_icache(unsigned long start, unsigned long end)
+{
+	unsigned long addr;
+
+	start &= ~(cpuinfo.icache_line_size - 1);
+	end += (cpuinfo.icache_line_size - 1);
+	end &= ~(cpuinfo.icache_line_size - 1);
+
+	if (end > start + cpuinfo.icache_size)
+		end = start + cpuinfo.icache_size;
+
+	for (addr = start; addr < end; addr += cpuinfo.icache_line_size) {
+		__asm__ __volatile__ ("   flushi %0\n"
+					: /* Outputs */
+					: /* Inputs  */ "r"(addr)
+					/* : No clobber */);
+	}
+	__asm__ __volatile(" flushp\n");
+}
+
+static void flush_aliases(struct address_space *mapping, struct page *page)
+{
+	struct mm_struct *mm = current->active_mm;
+	struct vm_area_struct *mpnt;
+	pgoff_t pgoff;
+
+	pgoff = page->index;
+
+	flush_dcache_mmap_lock(mapping);
+	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
+		unsigned long offset;
+
+		if (mpnt->vm_mm != mm)
+			continue;
+		if (!(mpnt->vm_flags & VM_MAYSHARE))
+			continue;
+
+		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+		flush_cache_page(mpnt, mpnt->vm_start + offset,
+			page_to_pfn(page));
+	}
+	flush_dcache_mmap_unlock(mapping);
+}
+
+void flush_cache_all(void)
+{
+	__flush_dcache(0, cpuinfo.dcache_size);
+	__flush_icache(0, cpuinfo.icache_size);
+}
+
+void flush_cache_mm(struct mm_struct *mm)
+{
+	flush_cache_all();
+}
+
+void flush_cache_dup_mm(struct mm_struct *mm)
+{
+	flush_cache_all();
+}
+
+void flush_icache_range(unsigned long start, unsigned long end)
+{
+	__flush_dcache(start, end);
+	__flush_icache(start, end);
+}
+
+void flush_dcache_range(unsigned long start, unsigned long end)
+{
+	__flush_dcache(start, end);
+	__flush_icache(start, end);
+}
+EXPORT_SYMBOL(flush_dcache_range);
+
+void invalidate_dcache_range(unsigned long start, unsigned long end)
+{
+	__invalidate_dcache(start, end);
+}
+EXPORT_SYMBOL(invalidate_dcache_range);
+
+void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
+			unsigned long end)
+{
+	__flush_dcache(start, end);
+	if (vma == NULL || (vma->vm_flags & VM_EXEC))
+		__flush_icache(start, end);
+}
+
+void flush_icache_page(struct vm_area_struct *vma, struct page *page)
+{
+	unsigned long start = (unsigned long) page_address(page);
+	unsigned long end = start + PAGE_SIZE;
+
+	__flush_dcache(start, end);
+	__flush_icache(start, end);
+}
+
+void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
+			unsigned long pfn)
+{
+	unsigned long start = vmaddr;
+	unsigned long end = start + PAGE_SIZE;
+
+	__flush_dcache(start, end);
+	if (vma->vm_flags & VM_EXEC)
+		__flush_icache(start, end);
+}
+
+void __flush_dcache_page(struct address_space *mapping, struct page *page)
+{
+	/*
+	 * Writeback any data associated with the kernel mapping of this
+	 * page.  This ensures that data in the physical page is mutually
+	 * coherent with the kernels mapping.
+	 */
+	unsigned long start = (unsigned long)page_address(page);
+
+	__flush_dcache(start, start + PAGE_SIZE);
+}
+
+void flush_dcache_page(struct page *page)
+{
+	struct address_space *mapping;
+
+	/*
+	 * The zero page is never written to, so never has any dirty
+	 * cache lines, and therefore never needs to be flushed.
+	 */
+	if (page == ZERO_PAGE(0))
+		return;
+
+	mapping = page_mapping_file(page);
+
+	/* Flush this page if there are aliases. */
+	if (mapping && !mapping_mapped(mapping)) {
+		clear_bit(PG_dcache_clean, &page->flags);
+	} else {
+		__flush_dcache_page(mapping, page);
+		if (mapping) {
+			unsigned long start = (unsigned long)page_address(page);
+			flush_aliases(mapping,  page);
+			flush_icache_range(start, start + PAGE_SIZE);
+		}
+		set_bit(PG_dcache_clean, &page->flags);
+	}
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+void update_mmu_cache(struct vm_area_struct *vma,
+		      unsigned long address, pte_t *ptep)
+{
+	pte_t pte = *ptep;
+	unsigned long pfn = pte_pfn(pte);
+	struct page *page;
+	struct address_space *mapping;
+
+	reload_tlb_page(vma, address, pte);
+
+	if (!pfn_valid(pfn))
+		return;
+
+	/*
+	* The zero page is never written to, so never has any dirty
+	* cache lines, and therefore never needs to be flushed.
+	*/
+	page = pfn_to_page(pfn);
+	if (page == ZERO_PAGE(0))
+		return;
+
+	mapping = page_mapping_file(page);
+	if (!test_and_set_bit(PG_dcache_clean, &page->flags))
+		__flush_dcache_page(mapping, page);
+
+	if(mapping)
+	{
+		flush_aliases(mapping, page);
+		if (vma->vm_flags & VM_EXEC)
+			flush_icache_page(vma, page);
+	}
+}
+
+void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
+		    struct page *to)
+{
+	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
+	__flush_icache(vaddr, vaddr + PAGE_SIZE);
+	copy_page(vto, vfrom);
+	__flush_dcache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
+	__flush_icache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
+}
+
+void clear_user_page(void *addr, unsigned long vaddr, struct page *page)
+{
+	__flush_dcache(vaddr, vaddr + PAGE_SIZE);
+	__flush_icache(vaddr, vaddr + PAGE_SIZE);
+	clear_page(addr);
+	__flush_dcache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
+	__flush_icache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
+}
+
+void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+			unsigned long user_vaddr,
+			void *dst, void *src, int len)
+{
+	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
+	memcpy(dst, src, len);
+	__flush_dcache((unsigned long)src, (unsigned long)src + len);
+	if (vma->vm_flags & VM_EXEC)
+		__flush_icache((unsigned long)src, (unsigned long)src + len);
+}
+
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+			unsigned long user_vaddr,
+			void *dst, void *src, int len)
+{
+	flush_cache_page(vma, user_vaddr, page_to_pfn(page));
+	memcpy(dst, src, len);
+	__flush_dcache((unsigned long)dst, (unsigned long)dst + len);
+	if (vma->vm_flags & VM_EXEC)
+		__flush_icache((unsigned long)dst, (unsigned long)dst + len);
+}
diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
new file mode 100644
index 000000000..fd887d5f3
--- /dev/null
+++ b/arch/nios2/mm/dma-mapping.c
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *  Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * Based on DMA code from MIPS.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/cache.h>
+#include <asm/cacheflush.h>
+
+void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir)
+{
+	void *vaddr = phys_to_virt(paddr);
+
+	switch (dir) {
+	case DMA_FROM_DEVICE:
+		invalidate_dcache_range((unsigned long)vaddr,
+			(unsigned long)(vaddr + size));
+		break;
+	case DMA_TO_DEVICE:
+		/*
+		 * We just need to flush the caches here , but Nios2 flush
+		 * instruction will do both writeback and invalidate.
+		 */
+	case DMA_BIDIRECTIONAL: /* flush and invalidate */
+		flush_dcache_range((unsigned long)vaddr,
+			(unsigned long)(vaddr + size));
+		break;
+	default:
+		BUG();
+	}
+}
+
+void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir)
+{
+	void *vaddr = phys_to_virt(paddr);
+
+	switch (dir) {
+	case DMA_BIDIRECTIONAL:
+	case DMA_FROM_DEVICE:
+		invalidate_dcache_range((unsigned long)vaddr,
+			(unsigned long)(vaddr + size));
+		break;
+	case DMA_TO_DEVICE:
+		break;
+	default:
+		BUG();
+	}
+}
+
+void arch_dma_prep_coherent(struct page *page, size_t size)
+{
+	unsigned long start = (unsigned long)page_address(page);
+
+	flush_dcache_range(start, start + size);
+}
+
+void *arch_dma_set_uncached(void *ptr, size_t size)
+{
+	unsigned long addr = (unsigned long)ptr;
+
+	addr |= CONFIG_NIOS2_IO_REGION_BASE;
+
+	return (void *)ptr;
+}
diff --git a/arch/nios2/mm/extable.c b/arch/nios2/mm/extable.c
new file mode 100644
index 000000000..2574dba04
--- /dev/null
+++ b/arch/nios2/mm/extable.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2010, Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009, Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/extable.h>
+#include <linux/uaccess.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+	const struct exception_table_entry *fixup;
+
+	fixup = search_exception_tables(regs->ea);
+	if (fixup) {
+		regs->ea = fixup->fixup;
+		return 1;
+	}
+
+	return 0;
+}
diff --git a/arch/nios2/mm/fault.c b/arch/nios2/mm/fault.c
new file mode 100644
index 000000000..71939fb28
--- /dev/null
+++ b/arch/nios2/mm/fault.c
@@ -0,0 +1,261 @@
+/*
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * based on arch/mips/mm/fault.c which is:
+ *
+ * Copyright (C) 1995-2000 Ralf Baechle
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/extable.h>
+#include <linux/uaccess.h>
+#include <linux/perf_event.h>
+
+#include <asm/mmu_context.h>
+#include <asm/traps.h>
+
+#define EXC_SUPERV_INSN_ACCESS	9  /* Supervisor only instruction address */
+#define EXC_SUPERV_DATA_ACCESS	11 /* Supervisor only data address */
+#define EXC_X_PROTECTION_FAULT	13 /* TLB permission violation (x) */
+#define EXC_R_PROTECTION_FAULT	14 /* TLB permission violation (r) */
+#define EXC_W_PROTECTION_FAULT	15 /* TLB permission violation (w) */
+
+/*
+ * This routine handles page faults.  It determines the address,
+ * and the problem, and then passes it off to one of the appropriate
+ * routines.
+ */
+asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long cause,
+				unsigned long address)
+{
+	struct vm_area_struct *vma = NULL;
+	struct task_struct *tsk = current;
+	struct mm_struct *mm = tsk->mm;
+	int code = SEGV_MAPERR;
+	vm_fault_t fault;
+	unsigned int flags = FAULT_FLAG_DEFAULT;
+
+	cause >>= 2;
+
+	/* Restart the instruction */
+	regs->ea -= 4;
+
+	/*
+	 * We fault-in kernel-space virtual memory on-demand. The
+	 * 'reference' page table is init_mm.pgd.
+	 *
+	 * NOTE! We MUST NOT take any locks for this case. We may
+	 * be in an interrupt or a critical region, and should
+	 * only copy the information from the master page table,
+	 * nothing more.
+	 */
+	if (unlikely(address >= VMALLOC_START && address <= VMALLOC_END)) {
+		if (user_mode(regs))
+			goto bad_area_nosemaphore;
+		else
+			goto vmalloc_fault;
+	}
+
+	if (unlikely(address >= TASK_SIZE))
+		goto bad_area_nosemaphore;
+
+	/*
+	 * If we're in an interrupt or have no user
+	 * context, we must not take the fault..
+	 */
+	if (faulthandler_disabled() || !mm)
+		goto bad_area_nosemaphore;
+
+	if (user_mode(regs))
+		flags |= FAULT_FLAG_USER;
+
+	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
+
+retry:
+	vma = lock_mm_and_find_vma(mm, address, regs);
+	if (!vma)
+		goto bad_area_nosemaphore;
+/*
+ * Ok, we have a good vm_area for this memory access, so
+ * we can handle it..
+ */
+	code = SEGV_ACCERR;
+
+	switch (cause) {
+	case EXC_SUPERV_INSN_ACCESS:
+		goto bad_area;
+	case EXC_SUPERV_DATA_ACCESS:
+		goto bad_area;
+	case EXC_X_PROTECTION_FAULT:
+		if (!(vma->vm_flags & VM_EXEC))
+			goto bad_area;
+		break;
+	case EXC_R_PROTECTION_FAULT:
+		if (!(vma->vm_flags & VM_READ))
+			goto bad_area;
+		break;
+	case EXC_W_PROTECTION_FAULT:
+		if (!(vma->vm_flags & VM_WRITE))
+			goto bad_area;
+		flags = FAULT_FLAG_WRITE;
+		break;
+	}
+
+	/*
+	 * If for any reason at all we couldn't handle the fault,
+	 * make sure we exit gracefully rather than endlessly redo
+	 * the fault.
+	 */
+	fault = handle_mm_fault(vma, address, flags, regs);
+
+	if (fault_signal_pending(fault, regs))
+		return;
+
+	/* The fault is fully completed (including releasing mmap lock) */
+	if (fault & VM_FAULT_COMPLETED)
+		return;
+
+	if (unlikely(fault & VM_FAULT_ERROR)) {
+		if (fault & VM_FAULT_OOM)
+			goto out_of_memory;
+		else if (fault & VM_FAULT_SIGSEGV)
+			goto bad_area;
+		else if (fault & VM_FAULT_SIGBUS)
+			goto do_sigbus;
+		BUG();
+	}
+
+	if (fault & VM_FAULT_RETRY) {
+		flags |= FAULT_FLAG_TRIED;
+
+		/*
+		 * No need to mmap_read_unlock(mm) as we would
+		 * have already released it in __lock_page_or_retry
+		 * in mm/filemap.c.
+		 */
+
+		goto retry;
+	}
+
+	mmap_read_unlock(mm);
+	return;
+
+/*
+ * Something tried to access memory that isn't in our memory map..
+ * Fix it, but check if it's kernel or user first..
+ */
+bad_area:
+	mmap_read_unlock(mm);
+
+bad_area_nosemaphore:
+	/* User mode accesses just cause a SIGSEGV */
+	if (user_mode(regs)) {
+		if (unhandled_signal(current, SIGSEGV) && printk_ratelimit()) {
+			pr_info("%s: unhandled page fault (%d) at 0x%08lx, "
+				"cause %ld\n", current->comm, SIGSEGV, address, cause);
+			show_regs(regs);
+		}
+		_exception(SIGSEGV, regs, code, address);
+		return;
+	}
+
+no_context:
+	/* Are we prepared to handle this kernel fault? */
+	if (fixup_exception(regs))
+		return;
+
+	/*
+	 * Oops. The kernel tried to access some bad page. We'll have to
+	 * terminate things with extreme prejudice.
+	 */
+	bust_spinlocks(1);
+
+	pr_alert("Unable to handle kernel %s at virtual address %08lx",
+		address < PAGE_SIZE ? "NULL pointer dereference" :
+		"paging request", address);
+	pr_alert("ea = %08lx, ra = %08lx, cause = %ld\n", regs->ea, regs->ra,
+		cause);
+	panic("Oops");
+	return;
+
+/*
+ * We ran out of memory, or some other thing happened to us that made
+ * us unable to handle the page fault gracefully.
+ */
+out_of_memory:
+	mmap_read_unlock(mm);
+	if (!user_mode(regs))
+		goto no_context;
+	pagefault_out_of_memory();
+	return;
+
+do_sigbus:
+	mmap_read_unlock(mm);
+
+	/* Kernel mode? Handle exceptions or die */
+	if (!user_mode(regs))
+		goto no_context;
+
+	_exception(SIGBUS, regs, BUS_ADRERR, address);
+	return;
+
+vmalloc_fault:
+	{
+		/*
+		 * Synchronize this task's top level page-table
+		 * with the 'reference' page table.
+		 *
+		 * Do _not_ use "tsk" here. We might be inside
+		 * an interrupt in the middle of a task switch..
+		 */
+		int offset = pgd_index(address);
+		pgd_t *pgd, *pgd_k;
+		p4d_t *p4d, *p4d_k;
+		pud_t *pud, *pud_k;
+		pmd_t *pmd, *pmd_k;
+		pte_t *pte_k;
+
+		pgd = pgd_current + offset;
+		pgd_k = init_mm.pgd + offset;
+
+		if (!pgd_present(*pgd_k))
+			goto no_context;
+		set_pgd(pgd, *pgd_k);
+
+		p4d = p4d_offset(pgd, address);
+		p4d_k = p4d_offset(pgd_k, address);
+		if (!p4d_present(*p4d_k))
+			goto no_context;
+		pud = pud_offset(p4d, address);
+		pud_k = pud_offset(p4d_k, address);
+		if (!pud_present(*pud_k))
+			goto no_context;
+		pmd = pmd_offset(pud, address);
+		pmd_k = pmd_offset(pud_k, address);
+		if (!pmd_present(*pmd_k))
+			goto no_context;
+		set_pmd(pmd, *pmd_k);
+
+		pte_k = pte_offset_kernel(pmd_k, address);
+		if (!pte_present(*pte_k))
+			goto no_context;
+
+		flush_tlb_kernel_page(address);
+		return;
+	}
+}
diff --git a/arch/nios2/mm/init.c b/arch/nios2/mm/init.c
new file mode 100644
index 000000000..7bc82ee88
--- /dev/null
+++ b/arch/nios2/mm/init.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ * Copyright (C) 2004 Microtronix Datacom Ltd
+ *
+ * based on arch/m68k/mm/init.c
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+#include <linux/binfmts.h>
+
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+#include <asm/mmu_context.h>
+#include <asm/cpuinfo.h>
+#include <asm/processor.h>
+
+pgd_t *pgd_current;
+
+/*
+ * paging_init() continues the virtual memory environment setup which
+ * was begun by the code in arch/head.S.
+ * The parameters are pointers to where to stick the starting and ending
+ * addresses of available kernel virtual memory.
+ */
+void __init paging_init(void)
+{
+	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
+
+	pagetable_init();
+	pgd_current = swapper_pg_dir;
+
+	max_zone_pfn[ZONE_NORMAL] = max_mapnr;
+
+	/* pass the memory from the bootmem allocator to the main allocator */
+	free_area_init(max_zone_pfn);
+
+	flush_dcache_range((unsigned long)empty_zero_page,
+			(unsigned long)empty_zero_page + PAGE_SIZE);
+}
+
+void __init mem_init(void)
+{
+	unsigned long end_mem   = memory_end; /* this must not include
+						kernel stack at top */
+
+	pr_debug("mem_init: start=%lx, end=%lx\n", memory_start, memory_end);
+
+	end_mem &= PAGE_MASK;
+	high_memory = __va(end_mem);
+
+	/* this will put all memory onto the freelists */
+	memblock_free_all();
+}
+
+void __init mmu_init(void)
+{
+	flush_tlb_all();
+}
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
+pte_t invalid_pte_table[PTRS_PER_PTE] __aligned(PAGE_SIZE);
+static struct page *kuser_page[1];
+
+static int alloc_kuser_page(void)
+{
+	extern char __kuser_helper_start[], __kuser_helper_end[];
+	int kuser_sz = __kuser_helper_end - __kuser_helper_start;
+	unsigned long vpage;
+
+	vpage = get_zeroed_page(GFP_ATOMIC);
+	if (!vpage)
+		return -ENOMEM;
+
+	/* Copy kuser helpers */
+	memcpy((void *)vpage, __kuser_helper_start, kuser_sz);
+
+	flush_icache_range(vpage, vpage + KUSER_SIZE);
+	kuser_page[0] = virt_to_page(vpage);
+
+	return 0;
+}
+arch_initcall(alloc_kuser_page);
+
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	struct mm_struct *mm = current->mm;
+	int ret;
+
+	mmap_write_lock(mm);
+
+	/* Map kuser helpers to user space address */
+	ret = install_special_mapping(mm, KUSER_BASE, KUSER_SIZE,
+				      VM_READ | VM_EXEC | VM_MAYREAD |
+				      VM_MAYEXEC, kuser_page);
+
+	mmap_write_unlock(mm);
+
+	return ret;
+}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+	return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL;
+}
+
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= MKP(0, 0, 0),
+	[VM_READ]					= MKP(0, 0, 1),
+	[VM_WRITE]					= MKP(0, 0, 0),
+	[VM_WRITE | VM_READ]				= MKP(0, 0, 1),
+	[VM_EXEC]					= MKP(1, 0, 0),
+	[VM_EXEC | VM_READ]				= MKP(1, 0, 1),
+	[VM_EXEC | VM_WRITE]				= MKP(1, 0, 0),
+	[VM_EXEC | VM_WRITE | VM_READ]			= MKP(1, 0, 1),
+	[VM_SHARED]					= MKP(0, 0, 0),
+	[VM_SHARED | VM_READ]				= MKP(0, 0, 1),
+	[VM_SHARED | VM_WRITE]				= MKP(0, 1, 0),
+	[VM_SHARED | VM_WRITE | VM_READ]		= MKP(0, 1, 1),
+	[VM_SHARED | VM_EXEC]				= MKP(1, 0, 0),
+	[VM_SHARED | VM_EXEC | VM_READ]			= MKP(1, 0, 1),
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= MKP(1, 1, 0),
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= MKP(1, 1, 1)
+};
+DECLARE_VM_GET_PAGE_PROT
diff --git a/arch/nios2/mm/ioremap.c b/arch/nios2/mm/ioremap.c
new file mode 100644
index 000000000..fe821efb9
--- /dev/null
+++ b/arch/nios2/mm/ioremap.c
@@ -0,0 +1,188 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+static inline void remap_area_pte(pte_t *pte, unsigned long address,
+				unsigned long size, unsigned long phys_addr,
+				unsigned long flags)
+{
+	unsigned long end;
+	unsigned long pfn;
+	pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | _PAGE_READ
+				| _PAGE_WRITE | flags);
+
+	address &= ~PMD_MASK;
+	end = address + size;
+	if (end > PMD_SIZE)
+		end = PMD_SIZE;
+	if (address >= end)
+		BUG();
+	pfn = PFN_DOWN(phys_addr);
+	do {
+		if (!pte_none(*pte)) {
+			pr_err("remap_area_pte: page already exists\n");
+			BUG();
+		}
+		set_pte(pte, pfn_pte(pfn, pgprot));
+		address += PAGE_SIZE;
+		pfn++;
+		pte++;
+	} while (address && (address < end));
+}
+
+static inline int remap_area_pmd(pmd_t *pmd, unsigned long address,
+				unsigned long size, unsigned long phys_addr,
+				unsigned long flags)
+{
+	unsigned long end;
+
+	address &= ~PGDIR_MASK;
+	end = address + size;
+	if (end > PGDIR_SIZE)
+		end = PGDIR_SIZE;
+	phys_addr -= address;
+	if (address >= end)
+		BUG();
+	do {
+		pte_t *pte = pte_alloc_kernel(pmd, address);
+
+		if (!pte)
+			return -ENOMEM;
+		remap_area_pte(pte, address, end - address, address + phys_addr,
+			flags);
+		address = (address + PMD_SIZE) & PMD_MASK;
+		pmd++;
+	} while (address && (address < end));
+	return 0;
+}
+
+static int remap_area_pages(unsigned long address, unsigned long phys_addr,
+				unsigned long size, unsigned long flags)
+{
+	int error;
+	pgd_t *dir;
+	unsigned long end = address + size;
+
+	phys_addr -= address;
+	dir = pgd_offset(&init_mm, address);
+	flush_cache_all();
+	if (address >= end)
+		BUG();
+	do {
+		p4d_t *p4d;
+		pud_t *pud;
+		pmd_t *pmd;
+
+		error = -ENOMEM;
+		p4d = p4d_alloc(&init_mm, dir, address);
+		if (!p4d)
+			break;
+		pud = pud_alloc(&init_mm, p4d, address);
+		if (!pud)
+			break;
+		pmd = pmd_alloc(&init_mm, pud, address);
+		if (!pmd)
+			break;
+		if (remap_area_pmd(pmd, address, end - address,
+			phys_addr + address, flags))
+			break;
+		error = 0;
+		address = (address + PGDIR_SIZE) & PGDIR_MASK;
+		dir++;
+	} while (address && (address < end));
+	flush_tlb_all();
+	return error;
+}
+
+#define IS_MAPPABLE_UNCACHEABLE(addr) (addr < 0x20000000UL)
+
+/*
+ * Map some physical address range into the kernel address space.
+ */
+void __iomem *ioremap(unsigned long phys_addr, unsigned long size)
+{
+	struct vm_struct *area;
+	unsigned long offset;
+	unsigned long last_addr;
+	void *addr;
+
+	/* Don't allow wraparound or zero size */
+	last_addr = phys_addr + size - 1;
+
+	if (!size || last_addr < phys_addr)
+		return NULL;
+
+	/* Don't allow anybody to remap normal RAM that we're using */
+	if (phys_addr > PHYS_OFFSET && phys_addr < virt_to_phys(high_memory)) {
+		char *t_addr, *t_end;
+		struct page *page;
+
+		t_addr = __va(phys_addr);
+		t_end = t_addr + (size - 1);
+		for (page = virt_to_page(t_addr);
+			page <= virt_to_page(t_end); page++)
+			if (!PageReserved(page))
+				return NULL;
+	}
+
+	/*
+	 * Map uncached objects in the low part of address space to
+	 * CONFIG_NIOS2_IO_REGION_BASE
+	 */
+	if (IS_MAPPABLE_UNCACHEABLE(phys_addr) &&
+	    IS_MAPPABLE_UNCACHEABLE(last_addr))
+		return (void __iomem *)(CONFIG_NIOS2_IO_REGION_BASE + phys_addr);
+
+	/* Mappings have to be page-aligned */
+	offset = phys_addr & ~PAGE_MASK;
+	phys_addr &= PAGE_MASK;
+	size = PAGE_ALIGN(last_addr + 1) - phys_addr;
+
+	/* Ok, go for it */
+	area = get_vm_area(size, VM_IOREMAP);
+	if (!area)
+		return NULL;
+	addr = area->addr;
+	if (remap_area_pages((unsigned long) addr, phys_addr, size, 0)) {
+		vunmap(addr);
+		return NULL;
+	}
+	return (void __iomem *) (offset + (char *)addr);
+}
+EXPORT_SYMBOL(ioremap);
+
+/*
+ * iounmap unmaps nearly everything, so be careful
+ * it doesn't free currently pointer/page tables anymore but it
+ * wasn't used anyway and might be added later.
+ */
+void iounmap(void __iomem *addr)
+{
+	struct vm_struct *p;
+
+	if ((unsigned long) addr > CONFIG_NIOS2_IO_REGION_BASE)
+		return;
+
+	p = remove_vm_area((void *) (PAGE_MASK & (unsigned long __force) addr));
+	if (!p)
+		pr_err("iounmap: bad address %p\n", addr);
+	kfree(p);
+}
+EXPORT_SYMBOL(iounmap);
diff --git a/arch/nios2/mm/mmu_context.c b/arch/nios2/mm/mmu_context.c
new file mode 100644
index 000000000..45d6b9c58
--- /dev/null
+++ b/arch/nios2/mm/mmu_context.c
@@ -0,0 +1,116 @@
+/*
+ * MMU context handling.
+ *
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/mm.h>
+
+#include <asm/cpuinfo.h>
+#include <asm/mmu_context.h>
+#include <asm/tlb.h>
+
+/* The pids position and mask in context */
+#define PID_SHIFT	0
+#define PID_BITS	(cpuinfo.tlb_pid_num_bits)
+#define PID_MASK	((1UL << PID_BITS) - 1)
+
+/* The versions position and mask in context */
+#define VERSION_BITS	(32 - PID_BITS)
+#define VERSION_SHIFT	(PID_SHIFT + PID_BITS)
+#define VERSION_MASK	((1UL << VERSION_BITS) - 1)
+
+/* Return the version part of a context */
+#define CTX_VERSION(c)	(((c) >> VERSION_SHIFT) & VERSION_MASK)
+
+/* Return the pid part of a context */
+#define CTX_PID(c)	(((c) >> PID_SHIFT) & PID_MASK)
+
+/* Value of the first context (version 1, pid 0) */
+#define FIRST_CTX	((1UL << VERSION_SHIFT) | (0 << PID_SHIFT))
+
+static mm_context_t next_mmu_context;
+
+/*
+ * Initialize MMU context management stuff.
+ */
+void __init mmu_context_init(void)
+{
+	/* We need to set this here because the value depends on runtime data
+	 * from cpuinfo */
+	next_mmu_context = FIRST_CTX;
+}
+
+/*
+ * Set new context (pid), keep way
+ */
+static void set_context(mm_context_t context)
+{
+	set_mmu_pid(CTX_PID(context));
+}
+
+static mm_context_t get_new_context(void)
+{
+	/* Return the next pid */
+	next_mmu_context += (1UL << PID_SHIFT);
+
+	/* If the pid field wraps around we increase the version and
+	 * flush the tlb */
+	if (unlikely(CTX_PID(next_mmu_context) == 0)) {
+		/* Version is incremented since the pid increment above
+		 * overflows info version */
+		flush_cache_all();
+		flush_tlb_all();
+	}
+
+	/* If the version wraps we start over with the first generation, we do
+	 * not need to flush the tlb here since it's always done above */
+	if (unlikely(CTX_VERSION(next_mmu_context) == 0))
+		next_mmu_context = FIRST_CTX;
+
+	return next_mmu_context;
+}
+
+void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+	       struct task_struct *tsk)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+
+	/* If the process context we are swapping in has a different context
+	 * generation then we have it should get a new generation/pid */
+	if (unlikely(CTX_VERSION(next->context) !=
+		CTX_VERSION(next_mmu_context)))
+		next->context = get_new_context();
+
+	/* Save the current pgd so the fast tlb handler can find it */
+	pgd_current = next->pgd;
+
+	/* Set the current context */
+	set_context(next->context);
+
+	local_irq_restore(flags);
+}
+
+/*
+ * After we have set current->mm to a new value, this activates
+ * the context for the new mm so we see the new mappings.
+ */
+void activate_mm(struct mm_struct *prev, struct mm_struct *next)
+{
+	next->context = get_new_context();
+	set_context(next->context);
+	pgd_current = next->pgd;
+}
+
+unsigned long get_pid_from_context(mm_context_t *context)
+{
+	return CTX_PID((*context));
+}
diff --git a/arch/nios2/mm/pgtable.c b/arch/nios2/mm/pgtable.c
new file mode 100644
index 000000000..7c76e8a74
--- /dev/null
+++ b/arch/nios2/mm/pgtable.c
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2009 Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/mm.h>
+#include <linux/sched.h>
+
+#include <asm/cpuinfo.h>
+
+/* pteaddr:
+ *   ptbase | vpn* | zero
+ *   31-22  | 21-2 | 1-0
+ *
+ *   *vpn is preserved on double fault
+ *
+ * tlbacc:
+ *   IG   |*flags| pfn
+ *   31-25|24-20 | 19-0
+ *
+ *   *crwxg
+ *
+ * tlbmisc:
+ *   resv  |way   |rd | we|pid |dbl|bad|perm|d
+ *   31-24 |23-20 |19 | 20|17-4|3  |2  |1   |0
+ *
+ */
+
+/*
+ * Initialize a new pgd / pmd table with invalid pointers.
+ */
+static void pgd_init(pgd_t *pgd)
+{
+	unsigned long *p = (unsigned long *) pgd;
+	int i;
+
+	for (i = 0; i < USER_PTRS_PER_PGD; i += 8) {
+		p[i + 0] = (unsigned long) invalid_pte_table;
+		p[i + 1] = (unsigned long) invalid_pte_table;
+		p[i + 2] = (unsigned long) invalid_pte_table;
+		p[i + 3] = (unsigned long) invalid_pte_table;
+		p[i + 4] = (unsigned long) invalid_pte_table;
+		p[i + 5] = (unsigned long) invalid_pte_table;
+		p[i + 6] = (unsigned long) invalid_pte_table;
+		p[i + 7] = (unsigned long) invalid_pte_table;
+	}
+}
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+	pgd_t *ret, *init;
+
+	ret = (pgd_t *) __get_free_page(GFP_KERNEL);
+	if (ret) {
+		init = pgd_offset(&init_mm, 0UL);
+		pgd_init(ret);
+		memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
+		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+	}
+
+	return ret;
+}
+
+void __init pagetable_init(void)
+{
+	/* Initialize the entire pgd.  */
+	pgd_init(swapper_pg_dir);
+	pgd_init(swapper_pg_dir + USER_PTRS_PER_PGD);
+}
diff --git a/arch/nios2/mm/tlb.c b/arch/nios2/mm/tlb.c
new file mode 100644
index 000000000..f90ac35f0
--- /dev/null
+++ b/arch/nios2/mm/tlb.c
@@ -0,0 +1,300 @@
+/*
+ * Nios2 TLB handling
+ *
+ * Copyright (C) 2009, Wind River Systems Inc
+ *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+
+#include <asm/tlb.h>
+#include <asm/mmu_context.h>
+#include <asm/cpuinfo.h>
+
+#define TLB_INDEX_MASK		\
+	((((1UL << (cpuinfo.tlb_ptr_sz - cpuinfo.tlb_num_ways_log2))) - 1) \
+		<< PAGE_SHIFT)
+
+static void get_misc_and_pid(unsigned long *misc, unsigned long *pid)
+{
+	*misc  = RDCTL(CTL_TLBMISC);
+	*misc &= (TLBMISC_PID | TLBMISC_WAY);
+	*pid  = *misc & TLBMISC_PID;
+}
+
+/*
+ * This provides a PTEADDR value for addr that will cause a TLB miss
+ * (fast TLB miss). TLB invalidation replaces entries with this value.
+ */
+static unsigned long pteaddr_invalid(unsigned long addr)
+{
+	return ((addr | 0xC0000000UL) >> PAGE_SHIFT) << 2;
+}
+
+/*
+ * This one is only used for pages with the global bit set so we don't care
+ * much about the ASID.
+ */
+static void replace_tlb_one_pid(unsigned long addr, unsigned long mmu_pid, unsigned long tlbacc)
+{
+	unsigned int way;
+	unsigned long org_misc, pid_misc;
+
+	/* remember pid/way until we return. */
+	get_misc_and_pid(&org_misc, &pid_misc);
+
+	WRCTL(CTL_PTEADDR, (addr >> PAGE_SHIFT) << 2);
+
+	for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
+		unsigned long pteaddr;
+		unsigned long tlbmisc;
+		unsigned long pid;
+
+		tlbmisc = TLBMISC_RD | (way << TLBMISC_WAY_SHIFT);
+		WRCTL(CTL_TLBMISC, tlbmisc);
+
+		pteaddr = RDCTL(CTL_PTEADDR);
+		if (((pteaddr >> 2) & 0xfffff) != (addr >> PAGE_SHIFT))
+			continue;
+
+		tlbmisc = RDCTL(CTL_TLBMISC);
+		pid = (tlbmisc >> TLBMISC_PID_SHIFT) & TLBMISC_PID_MASK;
+		if (pid != mmu_pid)
+			continue;
+
+		tlbmisc = (mmu_pid << TLBMISC_PID_SHIFT) | TLBMISC_WE |
+			  (way << TLBMISC_WAY_SHIFT);
+		WRCTL(CTL_TLBMISC, tlbmisc);
+		if (tlbacc == 0)
+			WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
+		WRCTL(CTL_TLBACC, tlbacc);
+		/*
+		 * There should be only a single entry that maps a
+		 * particular {address,pid} so break after a match.
+		 */
+		break;
+	}
+
+	WRCTL(CTL_TLBMISC, org_misc);
+}
+
+static void flush_tlb_one_pid(unsigned long addr, unsigned long mmu_pid)
+{
+	pr_debug("Flush tlb-entry for vaddr=%#lx\n", addr);
+
+	replace_tlb_one_pid(addr, mmu_pid, 0);
+}
+
+static void reload_tlb_one_pid(unsigned long addr, unsigned long mmu_pid, pte_t pte)
+{
+	pr_debug("Reload tlb-entry for vaddr=%#lx\n", addr);
+
+	replace_tlb_one_pid(addr, mmu_pid, pte_val(pte));
+}
+
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+			unsigned long end)
+{
+	unsigned long mmu_pid = get_pid_from_context(&vma->vm_mm->context);
+
+	while (start < end) {
+		flush_tlb_one_pid(start, mmu_pid);
+		start += PAGE_SIZE;
+	}
+}
+
+void reload_tlb_page(struct vm_area_struct *vma, unsigned long addr, pte_t pte)
+{
+	unsigned long mmu_pid = get_pid_from_context(&vma->vm_mm->context);
+
+	reload_tlb_one_pid(addr, mmu_pid, pte);
+}
+
+/*
+ * This one is only used for pages with the global bit set so we don't care
+ * much about the ASID.
+ */
+static void flush_tlb_one(unsigned long addr)
+{
+	unsigned int way;
+	unsigned long org_misc, pid_misc;
+
+	pr_debug("Flush tlb-entry for vaddr=%#lx\n", addr);
+
+	/* remember pid/way until we return. */
+	get_misc_and_pid(&org_misc, &pid_misc);
+
+	WRCTL(CTL_PTEADDR, (addr >> PAGE_SHIFT) << 2);
+
+	for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
+		unsigned long pteaddr;
+		unsigned long tlbmisc;
+
+		tlbmisc = TLBMISC_RD | (way << TLBMISC_WAY_SHIFT);
+		WRCTL(CTL_TLBMISC, tlbmisc);
+
+		pteaddr = RDCTL(CTL_PTEADDR);
+		if (((pteaddr >> 2) & 0xfffff) != (addr >> PAGE_SHIFT))
+			continue;
+
+		pr_debug("Flush entry by writing way=%dl pid=%ld\n",
+			 way, (pid_misc >> TLBMISC_PID_SHIFT));
+
+		tlbmisc = TLBMISC_WE | (way << TLBMISC_WAY_SHIFT);
+		WRCTL(CTL_TLBMISC, tlbmisc);
+		WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
+		WRCTL(CTL_TLBACC, 0);
+	}
+
+	WRCTL(CTL_TLBMISC, org_misc);
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	while (start < end) {
+		flush_tlb_one(start);
+		start += PAGE_SIZE;
+	}
+}
+
+void dump_tlb_line(unsigned long line)
+{
+	unsigned int way;
+	unsigned long org_misc;
+
+	pr_debug("dump tlb-entries for line=%#lx (addr %08lx)\n", line,
+		line << (PAGE_SHIFT + cpuinfo.tlb_num_ways_log2));
+
+	/* remember pid/way until we return */
+	org_misc = (RDCTL(CTL_TLBMISC) & (TLBMISC_PID | TLBMISC_WAY));
+
+	WRCTL(CTL_PTEADDR, line << 2);
+
+	for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
+		unsigned long pteaddr;
+		unsigned long tlbmisc;
+		unsigned long tlbacc;
+
+		WRCTL(CTL_TLBMISC, TLBMISC_RD | (way << TLBMISC_WAY_SHIFT));
+		pteaddr = RDCTL(CTL_PTEADDR);
+		tlbmisc = RDCTL(CTL_TLBMISC);
+		tlbacc = RDCTL(CTL_TLBACC);
+
+		if ((tlbacc << PAGE_SHIFT) != 0) {
+			pr_debug("-- way:%02x vpn:0x%08lx phys:0x%08lx pid:0x%02lx flags:%c%c%c%c%c\n",
+				way,
+				(pteaddr << (PAGE_SHIFT-2)),
+				(tlbacc << PAGE_SHIFT),
+				((tlbmisc >> TLBMISC_PID_SHIFT) &
+				TLBMISC_PID_MASK),
+				(tlbacc & _PAGE_READ ? 'r' : '-'),
+				(tlbacc & _PAGE_WRITE ? 'w' : '-'),
+				(tlbacc & _PAGE_EXEC ? 'x' : '-'),
+				(tlbacc & _PAGE_GLOBAL ? 'g' : '-'),
+				(tlbacc & _PAGE_CACHED ? 'c' : '-'));
+		}
+	}
+
+	WRCTL(CTL_TLBMISC, org_misc);
+}
+
+void dump_tlb(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < cpuinfo.tlb_num_lines; i++)
+		dump_tlb_line(i);
+}
+
+void flush_tlb_pid(unsigned long mmu_pid)
+{
+	unsigned long addr = 0;
+	unsigned int line;
+	unsigned int way;
+	unsigned long org_misc, pid_misc;
+
+	/* remember pid/way until we return */
+	get_misc_and_pid(&org_misc, &pid_misc);
+
+	for (line = 0; line < cpuinfo.tlb_num_lines; line++) {
+		WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
+
+		for (way = 0; way < cpuinfo.tlb_num_ways; way++) {
+			unsigned long tlbmisc;
+			unsigned long pid;
+
+			tlbmisc = TLBMISC_RD | (way << TLBMISC_WAY_SHIFT);
+			WRCTL(CTL_TLBMISC, tlbmisc);
+			tlbmisc = RDCTL(CTL_TLBMISC);
+			pid = (tlbmisc >> TLBMISC_PID_SHIFT) & TLBMISC_PID_MASK;
+			if (pid != mmu_pid)
+				continue;
+
+			tlbmisc = TLBMISC_WE | (way << TLBMISC_WAY_SHIFT);
+			WRCTL(CTL_TLBMISC, tlbmisc);
+			WRCTL(CTL_TLBACC, 0);
+		}
+
+		addr += PAGE_SIZE;
+	}
+
+	WRCTL(CTL_TLBMISC, org_misc);
+}
+
+/*
+ * All entries common to a mm share an asid.  To effectively flush these
+ * entries, we just bump the asid.
+ */
+void flush_tlb_mm(struct mm_struct *mm)
+{
+	if (current->mm == mm) {
+		unsigned long mmu_pid = get_pid_from_context(&mm->context);
+		flush_tlb_pid(mmu_pid);
+	} else {
+		memset(&mm->context, 0, sizeof(mm_context_t));
+	}
+}
+
+void flush_tlb_all(void)
+{
+	unsigned long addr = 0;
+	unsigned int line;
+	unsigned int way;
+	unsigned long org_misc, pid_misc;
+
+	/* remember pid/way until we return */
+	get_misc_and_pid(&org_misc, &pid_misc);
+
+	/* Start at way 0, way is auto-incremented after each TLBACC write */
+	WRCTL(CTL_TLBMISC, TLBMISC_WE);
+
+	/* Map each TLB entry to physcal address 0 with no-access and a
+	   bad ptbase */
+	for (line = 0; line < cpuinfo.tlb_num_lines; line++) {
+		WRCTL(CTL_PTEADDR, pteaddr_invalid(addr));
+		for (way = 0; way < cpuinfo.tlb_num_ways; way++)
+			WRCTL(CTL_TLBACC, 0);
+
+		addr += PAGE_SIZE;
+	}
+
+	/* restore pid/way */
+	WRCTL(CTL_TLBMISC, org_misc);
+}
+
+void set_mmu_pid(unsigned long pid)
+{
+	unsigned long tlbmisc;
+
+	tlbmisc = RDCTL(CTL_TLBMISC);
+	tlbmisc = (tlbmisc & TLBMISC_WAY);
+	tlbmisc |= (pid & TLBMISC_PID_MASK) << TLBMISC_PID_SHIFT;
+	WRCTL(CTL_TLBMISC, tlbmisc);
+}
diff --git a/arch/nios2/mm/uaccess.c b/arch/nios2/mm/uaccess.c
new file mode 100644
index 000000000..34f10af8e
--- /dev/null
+++ b/arch/nios2/mm/uaccess.c
@@ -0,0 +1,130 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009, Wind River Systems Inc
+ * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
+ */
+
+#include <linux/export.h>
+#include <linux/uaccess.h>
+
+asm(".global	raw_copy_from_user\n"
+	"   .type raw_copy_from_user, @function\n"
+	"raw_copy_from_user:\n"
+	"   movi  r2,7\n"
+	"   mov   r3,r4\n"
+	"   bge   r2,r6,1f\n"
+	"   xor   r2,r4,r5\n"
+	"   andi  r2,r2,3\n"
+	"   movi  r7,3\n"
+	"   beq   r2,zero,4f\n"
+	"1: addi  r6,r6,-1\n"
+	"   movi  r2,-1\n"
+	"   beq   r6,r2,3f\n"
+	"   mov   r7,r2\n"
+	"2: ldbu  r2,0(r5)\n"
+	"   addi  r6,r6,-1\n"
+	"   addi  r5,r5,1\n"
+	"   stb   r2,0(r3)\n"
+	"   addi  r3,r3,1\n"
+	"   bne   r6,r7,2b\n"
+	"3:\n"
+	"   addi  r2,r6,1\n"
+	"   ret\n"
+	"13:mov   r2,r6\n"
+	"   ret\n"
+	"4: andi  r2,r4,1\n"
+	"   cmpeq r2,r2,zero\n"
+	"   beq   r2,zero,7f\n"
+	"5: andi  r2,r3,2\n"
+	"   beq   r2,zero,6f\n"
+	"9: ldhu  r2,0(r5)\n"
+	"   addi  r6,r6,-2\n"
+	"   addi  r5,r5,2\n"
+	"   sth   r2,0(r3)\n"
+	"   addi  r3,r3,2\n"
+	"6: bge   r7,r6,1b\n"
+	"10:ldw   r2,0(r5)\n"
+	"   addi  r6,r6,-4\n"
+	"   addi  r5,r5,4\n"
+	"   stw   r2,0(r3)\n"
+	"   addi  r3,r3,4\n"
+	"   br    6b\n"
+	"7: ldbu  r2,0(r5)\n"
+	"   addi  r6,r6,-1\n"
+	"   addi  r5,r5,1\n"
+	"   addi  r3,r4,1\n"
+	"   stb   r2,0(r4)\n"
+	"   br    5b\n"
+	".section __ex_table,\"a\"\n"
+	".word 2b,3b\n"
+	".word 9b,13b\n"
+	".word 10b,13b\n"
+	".word 7b,13b\n"
+	".previous\n"
+	);
+EXPORT_SYMBOL(raw_copy_from_user);
+
+asm(
+	"   .global raw_copy_to_user\n"
+	"   .type raw_copy_to_user, @function\n"
+	"raw_copy_to_user:\n"
+	"   movi  r2,7\n"
+	"   mov   r3,r4\n"
+	"   bge   r2,r6,1f\n"
+	"   xor   r2,r4,r5\n"
+	"   andi  r2,r2,3\n"
+	"   movi  r7,3\n"
+	"   beq   r2,zero,4f\n"
+	/* Bail if we try to copy zero bytes  */
+	"1: addi  r6,r6,-1\n"
+	"   movi  r2,-1\n"
+	"   beq   r6,r2,3f\n"
+	/* Copy byte by byte for small copies and if src^dst != 0 */
+	"   mov   r7,r2\n"
+	"2: ldbu  r2,0(r5)\n"
+	"   addi  r5,r5,1\n"
+	"9: stb   r2,0(r3)\n"
+	"   addi  r6,r6,-1\n"
+	"   addi  r3,r3,1\n"
+	"   bne   r6,r7,2b\n"
+	"3: addi  r2,r6,1\n"
+	"   ret\n"
+	"13:mov   r2,r6\n"
+	"   ret\n"
+	/*  If 'to' is an odd address byte copy */
+	"4: andi  r2,r4,1\n"
+	"   cmpeq r2,r2,zero\n"
+	"   beq   r2,zero,7f\n"
+	/* If 'to' is not divideable by four copy halfwords */
+	"5: andi  r2,r3,2\n"
+	"   beq   r2,zero,6f\n"
+	"   ldhu  r2,0(r5)\n"
+	"   addi  r5,r5,2\n"
+	"10:sth   r2,0(r3)\n"
+	"   addi  r6,r6,-2\n"
+	"   addi  r3,r3,2\n"
+	/* Copy words */
+	"6: bge   r7,r6,1b\n"
+	"   ldw   r2,0(r5)\n"
+	"   addi  r5,r5,4\n"
+	"11:stw   r2,0(r3)\n"
+	"   addi  r6,r6,-4\n"
+	"   addi  r3,r3,4\n"
+	"   br    6b\n"
+	/* Copy remaining bytes */
+	"7: ldbu  r2,0(r5)\n"
+	"   addi  r5,r5,1\n"
+	"   addi  r3,r4,1\n"
+	"12: stb  r2,0(r4)\n"
+	"   addi  r6,r6,-1\n"
+	"   br    5b\n"
+	".section __ex_table,\"a\"\n"
+	".word 9b,3b\n"
+	".word 10b,13b\n"
+	".word 11b,13b\n"
+	".word 12b,13b\n"
+	".previous\n");
+EXPORT_SYMBOL(raw_copy_to_user);
diff --git a/arch/nios2/platform/Kconfig.platform b/arch/nios2/platform/Kconfig.platform
new file mode 100644
index 000000000..e849daff6
--- /dev/null
+++ b/arch/nios2/platform/Kconfig.platform
@@ -0,0 +1,148 @@
+# SPDX-License-Identifier: GPL-2.0-only
+menu "Platform options"
+
+comment "Memory settings"
+
+config NIOS2_MEM_BASE
+	hex "Memory base address"
+	default "0x00000000"
+	help
+	  This is the physical address of the memory that the kernel will run
+	  from. This address is used to link the kernel and setup initial memory
+	  management. You should take the raw memory address without any MMU
+	  or cache bits set.
+	  Please not that this address is used directly so you have to manually
+	  do address translation if it's connected to a bridge.
+
+comment "Device tree"
+
+config NIOS2_DTB_AT_PHYS_ADDR
+	bool "DTB at physical address"
+	help
+	  When enabled you can select a physical address to load the dtb from.
+	  Normally this address is passed by a bootloader such as u-boot but
+	  using this you can use a devicetree without a bootloader.
+	  This way you can store a devicetree in NOR flash or an onchip rom.
+	  Please note that this address is used directly so you have to manually
+	  do address translation if it's connected to a bridge. Also take into
+	  account that when using an MMU you'd have to ad 0xC0000000 to your
+	  address
+
+config NIOS2_DTB_PHYS_ADDR
+	hex "DTB Address"
+	depends on NIOS2_DTB_AT_PHYS_ADDR
+	default "0xC0000000"
+	help
+	  Physical address of a dtb blob.
+
+config NIOS2_DTB_SOURCE_BOOL
+	bool "Compile and link device tree into kernel image"
+	depends on !COMPILE_TEST
+	help
+	  This allows you to specify a dts (device tree source) file
+	  which will be compiled and linked into the kernel image.
+
+config NIOS2_DTB_SOURCE
+	string "Device tree source file"
+	depends on NIOS2_DTB_SOURCE_BOOL
+	default ""
+	help
+	  Absolute path to the device tree source (dts) file describing your
+	  system.
+
+comment "Nios II instructions"
+
+config NIOS2_ARCH_REVISION
+	int "Select Nios II architecture revision"
+	range 1 2
+	default 1
+	help
+	  Select between Nios II R1 and Nios II R2 . The architectures
+	  are binary incompatible. Default is R1 .
+
+config NIOS2_HW_MUL_SUPPORT
+	bool "Enable MUL instruction"
+	help
+	  Set to true if you configured the Nios II to include the MUL
+	  instruction.  This will enable the -mhw-mul compiler flag.
+
+config NIOS2_HW_MULX_SUPPORT
+	bool "Enable MULX instruction"
+	help
+	  Set to true if you configured the Nios II to include the MULX
+	  instruction.  Enables the -mhw-mulx compiler flag.
+
+config NIOS2_HW_DIV_SUPPORT
+	bool "Enable DIV instruction"
+	help
+	  Set to true if you configured the Nios II to include the DIV
+	  instruction.  Enables the -mhw-div compiler flag.
+
+config NIOS2_BMX_SUPPORT
+	bool "Enable BMX instructions"
+	depends on NIOS2_ARCH_REVISION = 2
+	help
+	  Set to true if you configured the Nios II R2 to include
+	  the BMX Bit Manipulation Extension instructions. Enables
+	  the -mbmx compiler flag.
+
+config NIOS2_CDX_SUPPORT
+	bool "Enable CDX instructions"
+	depends on NIOS2_ARCH_REVISION = 2
+	help
+	  Set to true if you configured the Nios II R2 to include
+	  the CDX Bit Manipulation Extension instructions. Enables
+	  the -mcdx compiler flag.
+
+config NIOS2_FPU_SUPPORT
+	bool "Custom floating point instr support"
+	help
+	  Enables the -mcustom-fpu-cfg=60-1 compiler flag.
+
+config NIOS2_CI_SWAB_SUPPORT
+	bool "Byteswap custom instruction"
+	help
+	  Use the byteswap (endian converter) Nios II custom instruction provided
+	  by Altera and which can be enabled in QSYS builder. This accelerates
+	  endian conversions in the kernel (e.g. ntohs).
+
+config NIOS2_CI_SWAB_NO
+	int "Byteswap custom instruction number" if NIOS2_CI_SWAB_SUPPORT
+	default 0
+	help
+	  Number of the instruction as configured in QSYS Builder.
+
+comment "Cache settings"
+
+config CUSTOM_CACHE_SETTINGS
+	bool "Custom cache settings"
+	help
+	  This option allows you to tweak the cache settings used during early
+	  boot (where the information from device tree is not yet available).
+	  There should be no reason to change these values. Linux will work
+	  perfectly fine, even if the Nios II is configured with smaller caches.
+
+	  Say N here unless you know what you are doing.
+
+config NIOS2_DCACHE_SIZE
+	hex "D-Cache size" if CUSTOM_CACHE_SETTINGS
+	range 0x200 0x10000
+	default "0x800"
+	help
+	  Maximum possible data cache size.
+
+config NIOS2_DCACHE_LINE_SIZE
+	hex "D-Cache line size" if CUSTOM_CACHE_SETTINGS
+	range 0x10 0x20
+	default "0x20"
+	help
+	  Minimum possible data cache line size.
+
+config NIOS2_ICACHE_SIZE
+	hex "I-Cache size" if CUSTOM_CACHE_SETTINGS
+	range 0x200 0x10000
+	default "0x1000"
+	help
+	  Maximum possible instruction cache size.
+
+endmenu
diff --git a/arch/nios2/platform/Makefile b/arch/nios2/platform/Makefile
new file mode 100644
index 000000000..fb5bdb44c
--- /dev/null
+++ b/arch/nios2/platform/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-y += platform.o
diff --git a/arch/nios2/platform/platform.c b/arch/nios2/platform/platform.c
new file mode 100644
index 000000000..9737a8712
--- /dev/null
+++ b/arch/nios2/platform/platform.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2013 Altera Corporation
+ * Copyright (C) 2011 Thomas Chou
+ * Copyright (C) 2011 Walter Goossens
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/of_fdt.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/sys_soc.h>
+#include <linux/io.h>
+#include <linux/clk-provider.h>
+
+static const struct of_device_id clk_match[] __initconst = {
+	{ .compatible = "fixed-clock", .data = of_fixed_clk_setup, },
+	{}
+};
+
+static int __init nios2_soc_device_init(void)
+{
+	struct soc_device *soc_dev;
+	struct soc_device_attribute *soc_dev_attr;
+	const char *machine;
+
+	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+	if (soc_dev_attr) {
+		machine = of_flat_dt_get_machine_name();
+		if (machine)
+			soc_dev_attr->machine = kasprintf(GFP_KERNEL, "%s",
+						machine);
+
+		soc_dev_attr->family = "Nios II";
+
+		soc_dev = soc_device_register(soc_dev_attr);
+		if (IS_ERR(soc_dev)) {
+			kfree(soc_dev_attr->machine);
+			kfree(soc_dev_attr);
+		}
+	}
+
+	of_clk_init(clk_match);
+
+	return 0;
+}
+
+device_initcall(nios2_soc_device_init);