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-rw-r--r--arch/arc/kernel/.gitignore2
-rw-r--r--arch/arc/kernel/Makefile29
-rw-r--r--arch/arc/kernel/arc_hostlink.c55
-rw-r--r--arch/arc/kernel/arcksyms.c54
-rw-r--r--arch/arc/kernel/asm-offsets.c84
-rw-r--r--arch/arc/kernel/ctx_sw_asm.S64
-rw-r--r--arch/arc/kernel/devtree.c76
-rw-r--r--arch/arc/kernel/disasm.c594
-rw-r--r--arch/arc/kernel/entry-arcv2.S249
-rw-r--r--arch/arc/kernel/entry-compact.S388
-rw-r--r--arch/arc/kernel/entry.S347
-rw-r--r--arch/arc/kernel/fpu.c82
-rw-r--r--arch/arc/kernel/head.S173
-rw-r--r--arch/arc/kernel/intc-arcv2.c191
-rw-r--r--arch/arc/kernel/intc-compact.c170
-rw-r--r--arch/arc/kernel/irq.c51
-rw-r--r--arch/arc/kernel/jump_label.c157
-rw-r--r--arch/arc/kernel/kgdb.c206
-rw-r--r--arch/arc/kernel/kprobes.c415
-rw-r--r--arch/arc/kernel/mcip.c419
-rw-r--r--arch/arc/kernel/module.c146
-rw-r--r--arch/arc/kernel/perf_event.c850
-rw-r--r--arch/arc/kernel/process.c296
-rw-r--r--arch/arc/kernel/ptrace.c401
-rw-r--r--arch/arc/kernel/reset.c31
-rw-r--r--arch/arc/kernel/setup.c654
-rw-r--r--arch/arc/kernel/signal.c443
-rw-r--r--arch/arc/kernel/smp.c414
-rw-r--r--arch/arc/kernel/stacktrace.c275
-rw-r--r--arch/arc/kernel/sys.c18
-rw-r--r--arch/arc/kernel/traps.c158
-rw-r--r--arch/arc/kernel/troubleshoot.c228
-rw-r--r--arch/arc/kernel/unaligned.c262
-rw-r--r--arch/arc/kernel/unwind.c1315
-rw-r--r--arch/arc/kernel/vmlinux.lds.S155
35 files changed, 9452 insertions, 0 deletions
diff --git a/arch/arc/kernel/.gitignore b/arch/arc/kernel/.gitignore
new file mode 100644
index 0000000000..bbb90f92d0
--- /dev/null
+++ b/arch/arc/kernel/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vmlinux.lds
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
new file mode 100644
index 0000000000..95fbf9364c
--- /dev/null
+++ b/arch/arc/kernel/Makefile
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+#
+
+obj-y := head.o arcksyms.o setup.o irq.o reset.o ptrace.o process.o devtree.o
+obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o
+obj-y += ctx_sw_asm.o
+
+obj-$(CONFIG_ISA_ARCOMPACT) += entry-compact.o intc-compact.o
+obj-$(CONFIG_ISA_ARCV2) += entry-arcv2.o intc-arcv2.o
+
+obj-$(CONFIG_MODULES) += arcksyms.o module.o
+obj-$(CONFIG_SMP) += smp.o
+obj-$(CONFIG_ARC_MCIP) += mcip.o
+obj-$(CONFIG_ARC_DW2_UNWIND) += unwind.o
+obj-$(CONFIG_KPROBES) += kprobes.o
+obj-$(CONFIG_ARC_EMUL_UNALIGNED) += unaligned.o
+obj-$(CONFIG_KGDB) += kgdb.o
+obj-$(CONFIG_ARC_METAWARE_HLINK) += arc_hostlink.o
+obj-$(CONFIG_PERF_EVENTS) += perf_event.o
+obj-$(CONFIG_JUMP_LABEL) += jump_label.o
+
+obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o
+ifdef CONFIG_ISA_ARCOMPACT
+CFLAGS_fpu.o += -mdpfp
+endif
+
+extra-y := vmlinux.lds
diff --git a/arch/arc/kernel/arc_hostlink.c b/arch/arc/kernel/arc_hostlink.c
new file mode 100644
index 0000000000..08c5196efe
--- /dev/null
+++ b/arch/arc/kernel/arc_hostlink.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arc_hostlink.c: Pseudo-driver for Metaware provided "hostlink" facility
+ *
+ * Allows Linux userland access to host in absence of any peripherals.
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/fs.h> /* file_operations */
+#include <linux/miscdevice.h>
+#include <linux/mm.h> /* VM_IO */
+#include <linux/module.h>
+#include <linux/uaccess.h>
+
+static unsigned char __HOSTLINK__[4 * PAGE_SIZE] __aligned(PAGE_SIZE);
+
+static int arc_hl_mmap(struct file *fp, struct vm_area_struct *vma)
+{
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+ if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
+ vma->vm_end - vma->vm_start,
+ vma->vm_page_prot)) {
+ pr_warn("Hostlink buffer mmap ERROR\n");
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static long arc_hl_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ /* we only support, returning the physical addr to mmap in user space */
+ put_user((unsigned int)__HOSTLINK__, (int __user *)arg);
+ return 0;
+}
+
+static const struct file_operations arc_hl_fops = {
+ .unlocked_ioctl = arc_hl_ioctl,
+ .mmap = arc_hl_mmap,
+};
+
+static struct miscdevice arc_hl_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "hostlink",
+ .fops = &arc_hl_fops
+};
+
+static int __init arc_hl_init(void)
+{
+ pr_info("ARC Hostlink driver mmap at 0x%p\n", __HOSTLINK__);
+ return misc_register(&arc_hl_dev);
+}
+module_init(arc_hl_init);
diff --git a/arch/arc/kernel/arcksyms.c b/arch/arc/kernel/arcksyms.c
new file mode 100644
index 0000000000..8851c0a19e
--- /dev/null
+++ b/arch/arc/kernel/arcksyms.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arcksyms.c - Exporting symbols not exportable from their own sources
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/module.h>
+
+/* libgcc functions, not part of kernel sources */
+extern void __ashldi3(void);
+extern void __ashrdi3(void);
+extern void __divsi3(void);
+extern void __divsf3(void);
+extern void __lshrdi3(void);
+extern void __modsi3(void);
+extern void __muldi3(void);
+extern void __ucmpdi2(void);
+extern void __udivsi3(void);
+extern void __umodsi3(void);
+extern void __cmpdi2(void);
+extern void __fixunsdfsi(void);
+extern void __muldf3(void);
+extern void __divdf3(void);
+extern void __floatunsidf(void);
+extern void __floatunsisf(void);
+extern void __udivdi3(void);
+
+EXPORT_SYMBOL(__ashldi3);
+EXPORT_SYMBOL(__ashrdi3);
+EXPORT_SYMBOL(__divsi3);
+EXPORT_SYMBOL(__divsf3);
+EXPORT_SYMBOL(__lshrdi3);
+EXPORT_SYMBOL(__modsi3);
+EXPORT_SYMBOL(__muldi3);
+EXPORT_SYMBOL(__ucmpdi2);
+EXPORT_SYMBOL(__udivsi3);
+EXPORT_SYMBOL(__umodsi3);
+EXPORT_SYMBOL(__cmpdi2);
+EXPORT_SYMBOL(__fixunsdfsi);
+EXPORT_SYMBOL(__muldf3);
+EXPORT_SYMBOL(__divdf3);
+EXPORT_SYMBOL(__floatunsidf);
+EXPORT_SYMBOL(__floatunsisf);
+EXPORT_SYMBOL(__udivdi3);
+
+/* ARC optimised assembler routines */
+EXPORT_SYMBOL(memset);
+EXPORT_SYMBOL(memcpy);
+EXPORT_SYMBOL(memcmp);
+EXPORT_SYMBOL(strchr);
+EXPORT_SYMBOL(strcpy);
+EXPORT_SYMBOL(strcmp);
+EXPORT_SYMBOL(strlen);
diff --git a/arch/arc/kernel/asm-offsets.c b/arch/arc/kernel/asm-offsets.c
new file mode 100644
index 0000000000..f77deb7991
--- /dev/null
+++ b/arch/arc/kernel/asm-offsets.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/thread_info.h>
+#include <linux/kbuild.h>
+#include <linux/ptrace.h>
+#include <asm/hardirq.h>
+#include <asm/page.h>
+
+
+int main(void)
+{
+ DEFINE(TASK_THREAD, offsetof(struct task_struct, thread));
+ DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, stack));
+
+ BLANK();
+
+ DEFINE(THREAD_CALLEE_REG, offsetof(struct thread_struct, callee_reg));
+ DEFINE(THREAD_FAULT_ADDR,
+ offsetof(struct thread_struct, fault_address));
+
+ BLANK();
+
+ DEFINE(THREAD_INFO_KSP, offsetof(struct thread_info, ksp));
+ DEFINE(THREAD_INFO_FLAGS, offsetof(struct thread_info, flags));
+ DEFINE(THREAD_INFO_PREEMPT_COUNT,
+ offsetof(struct thread_info, preempt_count));
+
+ BLANK();
+
+ DEFINE(TASK_ACT_MM, offsetof(struct task_struct, active_mm));
+ DEFINE(TASK_TGID, offsetof(struct task_struct, tgid));
+ DEFINE(TASK_PID, offsetof(struct task_struct, pid));
+ DEFINE(TASK_COMM, offsetof(struct task_struct, comm));
+
+ DEFINE(MM_CTXT, offsetof(struct mm_struct, context));
+ DEFINE(MM_PGD, offsetof(struct mm_struct, pgd));
+
+ DEFINE(MM_CTXT_ASID, offsetof(mm_context_t, asid));
+
+ BLANK();
+
+ DEFINE(PT_status32, offsetof(struct pt_regs, status32));
+ DEFINE(PT_event, offsetof(struct pt_regs, ecr));
+ DEFINE(PT_bta, offsetof(struct pt_regs, bta));
+ DEFINE(PT_sp, offsetof(struct pt_regs, sp));
+ DEFINE(PT_r0, offsetof(struct pt_regs, r0));
+ DEFINE(PT_r1, offsetof(struct pt_regs, r1));
+ DEFINE(PT_r2, offsetof(struct pt_regs, r2));
+ DEFINE(PT_r3, offsetof(struct pt_regs, r3));
+ DEFINE(PT_r4, offsetof(struct pt_regs, r4));
+ DEFINE(PT_r5, offsetof(struct pt_regs, r5));
+ DEFINE(PT_r6, offsetof(struct pt_regs, r6));
+ DEFINE(PT_r7, offsetof(struct pt_regs, r7));
+ DEFINE(PT_r8, offsetof(struct pt_regs, r8));
+ DEFINE(PT_r10, offsetof(struct pt_regs, r10));
+ DEFINE(PT_r26, offsetof(struct pt_regs, r26));
+ DEFINE(PT_ret, offsetof(struct pt_regs, ret));
+ DEFINE(PT_blink, offsetof(struct pt_regs, blink));
+ OFFSET(PT_fp, pt_regs, fp);
+ DEFINE(PT_lpe, offsetof(struct pt_regs, lp_end));
+ DEFINE(PT_lpc, offsetof(struct pt_regs, lp_count));
+#ifdef CONFIG_ISA_ARCV2
+ OFFSET(PT_r12, pt_regs, r12);
+ OFFSET(PT_r30, pt_regs, r30);
+#endif
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+ OFFSET(PT_r58, pt_regs, r58);
+ OFFSET(PT_r59, pt_regs, r59);
+#endif
+#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
+ OFFSET(PT_DSP_CTRL, pt_regs, DSP_CTRL);
+#endif
+
+ DEFINE(SZ_CALLEE_REGS, sizeof(struct callee_regs));
+ DEFINE(SZ_PT_REGS, sizeof(struct pt_regs));
+
+ return 0;
+}
diff --git a/arch/arc/kernel/ctx_sw_asm.S b/arch/arc/kernel/ctx_sw_asm.S
new file mode 100644
index 0000000000..48e1f21976
--- /dev/null
+++ b/arch/arc/kernel/ctx_sw_asm.S
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Vineetg: Aug 2009
+ * -Moved core context switch macro out of entry.S into this file.
+ * -This is the more "natural" hand written assembler
+ */
+
+#include <linux/linkage.h>
+#include <asm/entry.h> /* For the SAVE_* macros */
+#include <asm/asm-offsets.h>
+
+; IN
+; - r0: prev task (also current)
+; - r1: next task
+; OUT
+; - r0: prev task (so r0 not touched)
+
+ .section .sched.text,"ax",@progbits
+ENTRY_CFI(__switch_to)
+
+ /* save kernel stack frame regs of @prev task */
+ push blink
+ CFI_DEF_CFA_OFFSET 4
+ CFI_OFFSET r31, -4
+
+ push fp
+ CFI_DEF_CFA_OFFSET 8
+ CFI_OFFSET r27, -8
+
+ mov fp, sp
+ CFI_DEF_CFA_REGISTER r27
+
+ /* kernel mode callee regs of @prev */
+ SAVE_CALLEE_SAVED_KERNEL
+
+ /*
+ * save final SP to @prev->thread_info.ksp
+ * @prev is "current" so thread_info derived from SP
+ */
+ GET_CURR_THR_INFO_FROM_SP r10
+ st sp, [r10, THREAD_INFO_KSP]
+
+ /* update @next in _current_task[] and GP register caching it */
+ SET_CURR_TASK_ON_CPU r1, r10
+
+ /* load SP from @next->thread_info.ksp */
+ ld r10, [r1, TASK_THREAD_INFO]
+ ld sp, [r10, THREAD_INFO_KSP]
+
+ /* restore callee regs, stack frame regs of @next */
+ RESTORE_CALLEE_SAVED_KERNEL
+
+ pop fp
+ CFI_RESTORE r27
+ CFI_DEF_CFA r28, 4
+
+ pop blink
+ CFI_RESTORE r31
+ CFI_DEF_CFA_OFFSET 0
+
+ j [blink]
+END_CFI(__switch_to)
diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
new file mode 100644
index 0000000000..4c9e61457b
--- /dev/null
+++ b/arch/arc/kernel/devtree.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Based on reduced version of METAG
+ */
+
+
+#include <linux/init.h>
+#include <linux/reboot.h>
+#include <linux/memblock.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <asm/mach_desc.h>
+#include <asm/serial.h>
+
+#ifdef CONFIG_SERIAL_EARLYCON
+
+static unsigned int __initdata arc_base_baud;
+
+unsigned int __init arc_early_base_baud(void)
+{
+ return arc_base_baud/16;
+}
+
+static void __init arc_set_early_base_baud(unsigned long dt_root)
+{
+ if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
+ arc_base_baud = 166666666; /* Fixed 166.6MHz clk (TB10x) */
+ else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") ||
+ of_flat_dt_is_compatible(dt_root, "snps,hsdk"))
+ arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x & HSDK) */
+ else
+ arc_base_baud = 50000000; /* Fixed default 50MHz */
+}
+#else
+#define arc_set_early_base_baud(dt_root)
+#endif
+
+static const void * __init arch_get_next_mach(const char *const **match)
+{
+ static const struct machine_desc *mdesc = __arch_info_begin;
+ const struct machine_desc *m = mdesc;
+
+ if (m >= __arch_info_end)
+ return NULL;
+
+ mdesc++;
+ *match = m->dt_compat;
+ return m;
+}
+
+/**
+ * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
+ * @dt: virtual address pointer to dt blob
+ *
+ * If a dtb was passed to the kernel, then use it to choose the correct
+ * machine_desc and to setup the system.
+ */
+const struct machine_desc * __init setup_machine_fdt(void *dt)
+{
+ const struct machine_desc *mdesc;
+ unsigned long dt_root;
+
+ if (!early_init_dt_scan(dt))
+ return NULL;
+
+ mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach);
+ if (!mdesc)
+ machine_halt();
+
+ dt_root = of_get_flat_dt_root();
+ arc_set_early_base_baud(dt_root);
+
+ return mdesc;
+}
diff --git a/arch/arc/kernel/disasm.c b/arch/arc/kernel/disasm.c
new file mode 100644
index 0000000000..ccc7e8c39e
--- /dev/null
+++ b/arch/arc/kernel/disasm.c
@@ -0,0 +1,594 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * several functions that help interpret ARC instructions
+ * used for unaligned accesses, kprobes and kgdb
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/types.h>
+#include <linux/kprobes.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <asm/disasm.h>
+
+#if defined(CONFIG_KGDB) || defined(CONFIG_ARC_EMUL_UNALIGNED) || \
+ defined(CONFIG_KPROBES)
+
+/* disasm_instr: Analyses instruction at addr, stores
+ * findings in *state
+ */
+void __kprobes disasm_instr(unsigned long addr, struct disasm_state *state,
+ int userspace, struct pt_regs *regs, struct callee_regs *cregs)
+{
+ int fieldA = 0;
+ int fieldC = 0, fieldCisReg = 0;
+ uint16_t word1 = 0, word0 = 0;
+ int subopcode, is_linked, op_format;
+ uint16_t *ins_ptr;
+ uint16_t ins_buf[4];
+ int bytes_not_copied = 0;
+
+ memset(state, 0, sizeof(struct disasm_state));
+
+ /* This fetches the upper part of the 32 bit instruction
+ * in both the cases of Little Endian or Big Endian configurations. */
+ if (userspace) {
+ bytes_not_copied = copy_from_user(ins_buf,
+ (const void __user *) addr, 8);
+ if (bytes_not_copied > 6)
+ goto fault;
+ ins_ptr = ins_buf;
+ } else {
+ ins_ptr = (uint16_t *) addr;
+ }
+
+ word1 = *((uint16_t *)addr);
+
+ state->major_opcode = (word1 >> 11) & 0x1F;
+
+ /* Check if the instruction is 32 bit or 16 bit instruction */
+ if (state->major_opcode < 0x0B) {
+ if (bytes_not_copied > 4)
+ goto fault;
+ state->instr_len = 4;
+ word0 = *((uint16_t *)(addr+2));
+ state->words[0] = (word1 << 16) | word0;
+ } else {
+ state->instr_len = 2;
+ state->words[0] = word1;
+ }
+
+ /* Read the second word in case of limm */
+ word1 = *((uint16_t *)(addr + state->instr_len));
+ word0 = *((uint16_t *)(addr + state->instr_len + 2));
+ state->words[1] = (word1 << 16) | word0;
+
+ switch (state->major_opcode) {
+ case op_Bcc:
+ state->is_branch = 1;
+
+ /* unconditional branch s25, conditional branch s21 */
+ fieldA = (IS_BIT(state->words[0], 16)) ?
+ FIELD_s25(state->words[0]) :
+ FIELD_s21(state->words[0]);
+
+ state->delay_slot = IS_BIT(state->words[0], 5);
+ state->target = fieldA + (addr & ~0x3);
+ state->flow = direct_jump;
+ break;
+
+ case op_BLcc:
+ if (IS_BIT(state->words[0], 16)) {
+ /* Branch and Link*/
+ /* unconditional branch s25, conditional branch s21 */
+ fieldA = (IS_BIT(state->words[0], 17)) ?
+ (FIELD_s25(state->words[0]) & ~0x3) :
+ FIELD_s21(state->words[0]);
+
+ state->flow = direct_call;
+ } else {
+ /*Branch On Compare */
+ fieldA = FIELD_s9(state->words[0]) & ~0x3;
+ state->flow = direct_jump;
+ }
+
+ state->delay_slot = IS_BIT(state->words[0], 5);
+ state->target = fieldA + (addr & ~0x3);
+ state->is_branch = 1;
+ break;
+
+ case op_LD: /* LD<zz> a,[b,s9] */
+ state->write = 0;
+ state->di = BITS(state->words[0], 11, 11);
+ if (state->di)
+ break;
+ state->x = BITS(state->words[0], 6, 6);
+ state->zz = BITS(state->words[0], 7, 8);
+ state->aa = BITS(state->words[0], 9, 10);
+ state->wb_reg = FIELD_B(state->words[0]);
+ if (state->wb_reg == REG_LIMM) {
+ state->instr_len += 4;
+ state->aa = 0;
+ state->src1 = state->words[1];
+ } else {
+ state->src1 = get_reg(state->wb_reg, regs, cregs);
+ }
+ state->src2 = FIELD_s9(state->words[0]);
+ state->dest = FIELD_A(state->words[0]);
+ state->pref = (state->dest == REG_LIMM);
+ break;
+
+ case op_ST:
+ state->write = 1;
+ state->di = BITS(state->words[0], 5, 5);
+ if (state->di)
+ break;
+ state->aa = BITS(state->words[0], 3, 4);
+ state->zz = BITS(state->words[0], 1, 2);
+ state->src1 = FIELD_C(state->words[0]);
+ if (state->src1 == REG_LIMM) {
+ state->instr_len += 4;
+ state->src1 = state->words[1];
+ } else {
+ state->src1 = get_reg(state->src1, regs, cregs);
+ }
+ state->wb_reg = FIELD_B(state->words[0]);
+ if (state->wb_reg == REG_LIMM) {
+ state->aa = 0;
+ state->instr_len += 4;
+ state->src2 = state->words[1];
+ } else {
+ state->src2 = get_reg(state->wb_reg, regs, cregs);
+ }
+ state->src3 = FIELD_s9(state->words[0]);
+ break;
+
+ case op_MAJOR_4:
+ subopcode = MINOR_OPCODE(state->words[0]);
+ switch (subopcode) {
+ case 32: /* Jcc */
+ case 33: /* Jcc.D */
+ case 34: /* JLcc */
+ case 35: /* JLcc.D */
+ is_linked = 0;
+
+ if (subopcode == 33 || subopcode == 35)
+ state->delay_slot = 1;
+
+ if (subopcode == 34 || subopcode == 35)
+ is_linked = 1;
+
+ fieldCisReg = 0;
+ op_format = BITS(state->words[0], 22, 23);
+ if (op_format == 0 || ((op_format == 3) &&
+ (!IS_BIT(state->words[0], 5)))) {
+ fieldC = FIELD_C(state->words[0]);
+
+ if (fieldC == REG_LIMM) {
+ fieldC = state->words[1];
+ state->instr_len += 4;
+ } else {
+ fieldCisReg = 1;
+ }
+ } else if (op_format == 1 || ((op_format == 3)
+ && (IS_BIT(state->words[0], 5)))) {
+ fieldC = FIELD_C(state->words[0]);
+ } else {
+ /* op_format == 2 */
+ fieldC = FIELD_s12(state->words[0]);
+ }
+
+ if (!fieldCisReg) {
+ state->target = fieldC;
+ state->flow = is_linked ?
+ direct_call : direct_jump;
+ } else {
+ state->target = get_reg(fieldC, regs, cregs);
+ state->flow = is_linked ?
+ indirect_call : indirect_jump;
+ }
+ state->is_branch = 1;
+ break;
+
+ case 40: /* LPcc */
+ if (BITS(state->words[0], 22, 23) == 3) {
+ /* Conditional LPcc u7 */
+ fieldC = FIELD_C(state->words[0]);
+
+ fieldC = fieldC << 1;
+ fieldC += (addr & ~0x03);
+ state->is_branch = 1;
+ state->flow = direct_jump;
+ state->target = fieldC;
+ }
+ /* For Unconditional lp, next pc is the fall through
+ * which is updated */
+ break;
+
+ case 48 ... 55: /* LD a,[b,c] */
+ state->di = BITS(state->words[0], 15, 15);
+ if (state->di)
+ break;
+ state->x = BITS(state->words[0], 16, 16);
+ state->zz = BITS(state->words[0], 17, 18);
+ state->aa = BITS(state->words[0], 22, 23);
+ state->wb_reg = FIELD_B(state->words[0]);
+ if (state->wb_reg == REG_LIMM) {
+ state->instr_len += 4;
+ state->src1 = state->words[1];
+ } else {
+ state->src1 = get_reg(state->wb_reg, regs,
+ cregs);
+ }
+ state->src2 = FIELD_C(state->words[0]);
+ if (state->src2 == REG_LIMM) {
+ state->instr_len += 4;
+ state->src2 = state->words[1];
+ } else {
+ state->src2 = get_reg(state->src2, regs,
+ cregs);
+ }
+ state->dest = FIELD_A(state->words[0]);
+ if (state->dest == REG_LIMM)
+ state->pref = 1;
+ break;
+
+ case 10: /* MOV */
+ /* still need to check for limm to extract instr len */
+ /* MOV is special case because it only takes 2 args */
+ switch (BITS(state->words[0], 22, 23)) {
+ case 0: /* OP a,b,c */
+ if (FIELD_C(state->words[0]) == REG_LIMM)
+ state->instr_len += 4;
+ break;
+ case 1: /* OP a,b,u6 */
+ break;
+ case 2: /* OP b,b,s12 */
+ break;
+ case 3: /* OP.cc b,b,c/u6 */
+ if ((!IS_BIT(state->words[0], 5)) &&
+ (FIELD_C(state->words[0]) == REG_LIMM))
+ state->instr_len += 4;
+ break;
+ }
+ break;
+
+
+ default:
+ /* Not a Load, Jump or Loop instruction */
+ /* still need to check for limm to extract instr len */
+ switch (BITS(state->words[0], 22, 23)) {
+ case 0: /* OP a,b,c */
+ if ((FIELD_B(state->words[0]) == REG_LIMM) ||
+ (FIELD_C(state->words[0]) == REG_LIMM))
+ state->instr_len += 4;
+ break;
+ case 1: /* OP a,b,u6 */
+ break;
+ case 2: /* OP b,b,s12 */
+ break;
+ case 3: /* OP.cc b,b,c/u6 */
+ if ((!IS_BIT(state->words[0], 5)) &&
+ ((FIELD_B(state->words[0]) == REG_LIMM) ||
+ (FIELD_C(state->words[0]) == REG_LIMM)))
+ state->instr_len += 4;
+ break;
+ }
+ break;
+ }
+ break;
+
+ /* 16 Bit Instructions */
+ case op_LD_ADD: /* LD_S|LDB_S|LDW_S a,[b,c] */
+ state->zz = BITS(state->words[0], 3, 4);
+ state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs);
+ state->src2 = get_reg(FIELD_S_C(state->words[0]), regs, cregs);
+ state->dest = FIELD_S_A(state->words[0]);
+ break;
+
+ case op_ADD_MOV_CMP:
+ /* check for limm, ignore mov_s h,b (== mov_s 0,b) */
+ if ((BITS(state->words[0], 3, 4) < 3) &&
+ (FIELD_S_H(state->words[0]) == REG_LIMM))
+ state->instr_len += 4;
+ break;
+
+ case op_S:
+ subopcode = BITS(state->words[0], 5, 7);
+ switch (subopcode) {
+ case 0: /* j_s */
+ case 1: /* j_s.d */
+ case 2: /* jl_s */
+ case 3: /* jl_s.d */
+ state->target = get_reg(FIELD_S_B(state->words[0]),
+ regs, cregs);
+ state->delay_slot = subopcode & 1;
+ state->flow = (subopcode >= 2) ?
+ direct_call : indirect_jump;
+ break;
+ case 7:
+ switch (BITS(state->words[0], 8, 10)) {
+ case 4: /* jeq_s [blink] */
+ case 5: /* jne_s [blink] */
+ case 6: /* j_s [blink] */
+ case 7: /* j_s.d [blink] */
+ state->delay_slot = (subopcode == 7);
+ state->flow = indirect_jump;
+ state->target = get_reg(31, regs, cregs);
+ default:
+ break;
+ }
+ default:
+ break;
+ }
+ break;
+
+ case op_LD_S: /* LD_S c, [b, u7] */
+ state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs);
+ state->src2 = FIELD_S_u7(state->words[0]);
+ state->dest = FIELD_S_C(state->words[0]);
+ break;
+
+ case op_LDB_S:
+ case op_STB_S:
+ /* no further handling required as byte accesses should not
+ * cause an unaligned access exception */
+ state->zz = 1;
+ break;
+
+ case op_LDWX_S: /* LDWX_S c, [b, u6] */
+ state->x = 1;
+ fallthrough;
+
+ case op_LDW_S: /* LDW_S c, [b, u6] */
+ state->zz = 2;
+ state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs);
+ state->src2 = FIELD_S_u6(state->words[0]);
+ state->dest = FIELD_S_C(state->words[0]);
+ break;
+
+ case op_ST_S: /* ST_S c, [b, u7] */
+ state->write = 1;
+ state->src1 = get_reg(FIELD_S_C(state->words[0]), regs, cregs);
+ state->src2 = get_reg(FIELD_S_B(state->words[0]), regs, cregs);
+ state->src3 = FIELD_S_u7(state->words[0]);
+ break;
+
+ case op_STW_S: /* STW_S c,[b,u6] */
+ state->write = 1;
+ state->zz = 2;
+ state->src1 = get_reg(FIELD_S_C(state->words[0]), regs, cregs);
+ state->src2 = get_reg(FIELD_S_B(state->words[0]), regs, cregs);
+ state->src3 = FIELD_S_u6(state->words[0]);
+ break;
+
+ case op_SP: /* LD_S|LDB_S b,[sp,u7], ST_S|STB_S b,[sp,u7] */
+ /* note: we are ignoring possibility of:
+ * ADD_S, SUB_S, PUSH_S, POP_S as these should not
+ * cause unaligned exception anyway */
+ state->write = BITS(state->words[0], 6, 6);
+ state->zz = BITS(state->words[0], 5, 5);
+ if (state->zz)
+ break; /* byte accesses should not come here */
+ if (!state->write) {
+ state->src1 = get_reg(28, regs, cregs);
+ state->src2 = FIELD_S_u7(state->words[0]);
+ state->dest = FIELD_S_B(state->words[0]);
+ } else {
+ state->src1 = get_reg(FIELD_S_B(state->words[0]), regs,
+ cregs);
+ state->src2 = get_reg(28, regs, cregs);
+ state->src3 = FIELD_S_u7(state->words[0]);
+ }
+ break;
+
+ case op_GP: /* LD_S|LDB_S|LDW_S r0,[gp,s11/s9/s10] */
+ /* note: ADD_S r0, gp, s11 is ignored */
+ state->zz = BITS(state->words[0], 9, 10);
+ state->src1 = get_reg(26, regs, cregs);
+ state->src2 = state->zz ? FIELD_S_s10(state->words[0]) :
+ FIELD_S_s11(state->words[0]);
+ state->dest = 0;
+ break;
+
+ case op_Pcl: /* LD_S b,[pcl,u10] */
+ state->src1 = regs->ret & ~3;
+ state->src2 = FIELD_S_u10(state->words[0]);
+ state->dest = FIELD_S_B(state->words[0]);
+ break;
+
+ case op_BR_S:
+ state->target = FIELD_S_s8(state->words[0]) + (addr & ~0x03);
+ state->flow = direct_jump;
+ state->is_branch = 1;
+ break;
+
+ case op_B_S:
+ fieldA = (BITS(state->words[0], 9, 10) == 3) ?
+ FIELD_S_s7(state->words[0]) :
+ FIELD_S_s10(state->words[0]);
+ state->target = fieldA + (addr & ~0x03);
+ state->flow = direct_jump;
+ state->is_branch = 1;
+ break;
+
+ case op_BL_S:
+ state->target = FIELD_S_s13(state->words[0]) + (addr & ~0x03);
+ state->flow = direct_call;
+ state->is_branch = 1;
+ break;
+
+ default:
+ break;
+ }
+
+ if (bytes_not_copied <= (8 - state->instr_len))
+ return;
+
+fault: state->fault = 1;
+}
+
+long __kprobes get_reg(int reg, struct pt_regs *regs,
+ struct callee_regs *cregs)
+{
+ long *p;
+
+#if defined(CONFIG_ISA_ARCOMPACT)
+ if (reg <= 12) {
+ p = &regs->r0;
+ return p[-reg];
+ }
+#else /* CONFIG_ISA_ARCV2 */
+ if (reg <= 11) {
+ p = &regs->r0;
+ return p[reg];
+ }
+
+ if (reg == 12)
+ return regs->r12;
+ if (reg == 30)
+ return regs->r30;
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+ if (reg == 58)
+ return regs->r58;
+ if (reg == 59)
+ return regs->r59;
+#endif
+#endif
+ if (cregs && (reg <= 25)) {
+ p = &cregs->r13;
+ return p[13 - reg];
+ }
+
+ if (reg == 26)
+ return regs->r26;
+ if (reg == 27)
+ return regs->fp;
+ if (reg == 28)
+ return regs->sp;
+ if (reg == 31)
+ return regs->blink;
+
+ return 0;
+}
+
+void __kprobes set_reg(int reg, long val, struct pt_regs *regs,
+ struct callee_regs *cregs)
+{
+ long *p;
+
+#if defined(CONFIG_ISA_ARCOMPACT)
+ switch (reg) {
+ case 0 ... 12:
+ p = &regs->r0;
+ p[-reg] = val;
+ break;
+ case 13 ... 25:
+ if (cregs) {
+ p = &cregs->r13;
+ p[13 - reg] = val;
+ }
+ break;
+ case 26:
+ regs->r26 = val;
+ break;
+ case 27:
+ regs->fp = val;
+ break;
+ case 28:
+ regs->sp = val;
+ break;
+ case 31:
+ regs->blink = val;
+ break;
+ default:
+ break;
+ }
+#else /* CONFIG_ISA_ARCV2 */
+ switch (reg) {
+ case 0 ... 11:
+ p = &regs->r0;
+ p[reg] = val;
+ break;
+ case 12:
+ regs->r12 = val;
+ break;
+ case 13 ... 25:
+ if (cregs) {
+ p = &cregs->r13;
+ p[13 - reg] = val;
+ }
+ break;
+ case 26:
+ regs->r26 = val;
+ break;
+ case 27:
+ regs->fp = val;
+ break;
+ case 28:
+ regs->sp = val;
+ break;
+ case 30:
+ regs->r30 = val;
+ break;
+ case 31:
+ regs->blink = val;
+ break;
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+ case 58:
+ regs->r58 = val;
+ break;
+ case 59:
+ regs->r59 = val;
+ break;
+#endif
+ default:
+ break;
+ }
+#endif
+}
+
+/*
+ * Disassembles the insn at @pc and sets @next_pc to next PC (which could be
+ * @pc +2/4/6 (ARCompact ISA allows free intermixing of 16/32 bit insns).
+ *
+ * If @pc is a branch
+ * -@tgt_if_br is set to branch target.
+ * -If branch has delay slot, @next_pc updated with actual next PC.
+ */
+int __kprobes disasm_next_pc(unsigned long pc, struct pt_regs *regs,
+ struct callee_regs *cregs,
+ unsigned long *next_pc, unsigned long *tgt_if_br)
+{
+ struct disasm_state instr;
+
+ disasm_instr(pc, &instr, 0, regs, cregs);
+
+ *next_pc = pc + instr.instr_len;
+
+ /* Instruction with possible two targets branch, jump and loop */
+ if (instr.is_branch)
+ *tgt_if_br = instr.target;
+
+ /* For the instructions with delay slots, the fall through is the
+ * instruction following the instruction in delay slot.
+ */
+ if (instr.delay_slot) {
+ struct disasm_state instr_d;
+
+ disasm_instr(*next_pc, &instr_d, 0, regs, cregs);
+
+ *next_pc += instr_d.instr_len;
+ }
+
+ /* Zero Overhead Loop - end of the loop */
+ if (!(regs->status32 & STATUS32_L) && (*next_pc == regs->lp_end)
+ && (regs->lp_count > 1)) {
+ *next_pc = regs->lp_start;
+ }
+
+ return instr.is_branch;
+}
+
+#endif /* CONFIG_KGDB || CONFIG_ARC_EMUL_UNALIGNED || CONFIG_KPROBES */
diff --git a/arch/arc/kernel/entry-arcv2.S b/arch/arc/kernel/entry-arcv2.S
new file mode 100644
index 0000000000..2e49c81c80
--- /dev/null
+++ b/arch/arc/kernel/entry-arcv2.S
@@ -0,0 +1,249 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ARCv2 ISA based core Low Level Intr/Traps/Exceptions(non-TLB) Handling
+ *
+ * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/linkage.h> /* ARC_{EXTRY,EXIT} */
+#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,TRAP...} */
+#include <asm/errno.h>
+#include <asm/arcregs.h>
+#include <asm/irqflags.h>
+#include <asm/mmu.h>
+
+; A maximum number of supported interrupts in the core interrupt controller.
+; This number is not equal to the maximum interrupt number (256) because
+; first 16 lines are reserved for exceptions and are not configurable.
+#define NR_CPU_IRQS 240
+
+ .cpu HS
+
+#define VECTOR .word
+
+;############################ Vector Table #################################
+
+ .section .vector,"a",@progbits
+ .align 4
+
+# Initial 16 slots are Exception Vectors
+VECTOR res_service ; Reset Vector
+VECTOR mem_service ; Mem exception
+VECTOR instr_service ; Instrn Error
+VECTOR EV_MachineCheck ; Fatal Machine check
+VECTOR EV_TLBMissI ; Intruction TLB miss
+VECTOR EV_TLBMissD ; Data TLB miss
+VECTOR EV_TLBProtV ; Protection Violation
+VECTOR EV_PrivilegeV ; Privilege Violation
+VECTOR EV_SWI ; Software Breakpoint
+VECTOR EV_Trap ; Trap exception
+VECTOR EV_Extension ; Extn Instruction Exception
+VECTOR EV_DivZero ; Divide by Zero
+VECTOR EV_DCError ; Data Cache Error
+VECTOR EV_Misaligned ; Misaligned Data Access
+VECTOR reserved ; Reserved slots
+VECTOR reserved ; Reserved slots
+
+# Begin Interrupt Vectors
+VECTOR handle_interrupt ; (16) Timer0
+VECTOR handle_interrupt ; unused (Timer1)
+VECTOR handle_interrupt ; unused (WDT)
+VECTOR handle_interrupt ; (19) Inter core Interrupt (IPI)
+VECTOR handle_interrupt ; (20) perf Interrupt
+VECTOR handle_interrupt ; (21) Software Triggered Intr (Self IPI)
+VECTOR handle_interrupt ; unused
+VECTOR handle_interrupt ; (23) unused
+# End of fixed IRQs
+
+.rept NR_CPU_IRQS - 8
+ VECTOR handle_interrupt
+.endr
+
+ .section .text, "ax",@progbits
+
+reserved:
+ flag 1 ; Unexpected event, halt
+
+;##################### Interrupt Handling ##############################
+
+ENTRY(handle_interrupt)
+
+ INTERRUPT_PROLOGUE
+
+ # irq control APIs local_irq_save/restore/disable/enable fiddle with
+ # global interrupt enable bits in STATUS32 (.IE for 1 prio, .E[] for 2 prio)
+ # However a taken interrupt doesn't clear these bits. Thus irqs_disabled()
+ # query in hard ISR path would return false (since .IE is set) which would
+ # trips genirq interrupt handling asserts.
+ #
+ # So do a "soft" disable of interrutps here.
+ #
+ # Note this disable is only for consistent book-keeping as further interrupts
+ # will be disabled anyways even w/o this. Hardware tracks active interrupts
+ # seperately in AUX_IRQ_ACT.active and will not take new interrupts
+ # unless this one returns (or higher prio becomes pending in 2-prio scheme)
+
+ IRQ_DISABLE
+
+ ; icause is banked: one per priority level
+ ; so a higher prio interrupt taken here won't clobber prev prio icause
+ lr r0, [ICAUSE]
+ mov blink, ret_from_exception
+
+ b.d arch_do_IRQ
+ mov r1, sp
+
+END(handle_interrupt)
+
+;################### Non TLB Exception Handling #############################
+
+ENTRY(EV_SWI)
+ ; TODO: implement this
+ EXCEPTION_PROLOGUE
+ b ret_from_exception
+END(EV_SWI)
+
+ENTRY(EV_DivZero)
+ ; TODO: implement this
+ EXCEPTION_PROLOGUE
+ b ret_from_exception
+END(EV_DivZero)
+
+ENTRY(EV_DCError)
+ ; TODO: implement this
+ EXCEPTION_PROLOGUE
+ b ret_from_exception
+END(EV_DCError)
+
+; ---------------------------------------------
+; Memory Error Exception Handler
+; - Unlike ARCompact, handles Bus errors for both User/Kernel mode,
+; Instruction fetch or Data access, under a single Exception Vector
+; ---------------------------------------------
+
+ENTRY(mem_service)
+
+ EXCEPTION_PROLOGUE
+
+ bl do_memory_error
+ b ret_from_exception
+END(mem_service)
+
+ENTRY(EV_Misaligned)
+
+ EXCEPTION_PROLOGUE
+
+ SAVE_CALLEE_SAVED_USER
+ mov r2, sp ; callee_regs
+
+ bl do_misaligned_access
+
+ ; TBD: optimize - do this only if a callee reg was involved
+ ; either a dst of emulated LD/ST or src with address-writeback
+ RESTORE_CALLEE_SAVED_USER
+
+ b ret_from_exception
+END(EV_Misaligned)
+
+; ---------------------------------------------
+; Protection Violation Exception Handler
+; ---------------------------------------------
+
+ENTRY(EV_TLBProtV)
+
+ EXCEPTION_PROLOGUE
+
+ mov blink, ret_from_exception
+ b do_page_fault
+
+END(EV_TLBProtV)
+
+; From Linux standpoint Slow Path I/D TLB Miss is same a ProtV as they
+; need to call do_page_fault().
+; ECR in pt_regs provides whether access was R/W/X
+
+.global call_do_page_fault
+.set call_do_page_fault, EV_TLBProtV
+
+;############# Common Handlers for ARCompact and ARCv2 ##############
+
+#include "entry.S"
+
+;############# Return from Intr/Excp/Trap (ARCv2 ISA Specifics) ##############
+;
+; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap)
+; IRQ shd definitely not happen between now and rtie
+; All 2 entry points to here already disable interrupts
+
+.Lrestore_regs:
+restore_regs:
+
+ # Interrpts are actually disabled from this point on, but will get
+ # reenabled after we return from interrupt/exception.
+ # But irq tracer needs to be told now...
+ TRACE_ASM_IRQ_ENABLE
+
+ ld r0, [sp, PT_status32] ; U/K mode at time of entry
+ lr r10, [AUX_IRQ_ACT]
+
+ bmsk r11, r10, 15 ; extract AUX_IRQ_ACT.active
+ breq r11, 0, .Lexcept_ret ; No intr active, ret from Exception
+
+;####### Return from Intr #######
+
+.Lisr_ret:
+
+debug_marker_l1:
+ ; bbit1.nt r0, STATUS_DE_BIT, .Lintr_ret_to_delay_slot
+ btst r0, STATUS_DE_BIT ; Z flag set if bit clear
+ bnz .Lintr_ret_to_delay_slot ; branch if STATUS_DE_BIT set
+
+ ; Handle special case #1: (Entry via Exception, Return via IRQ)
+ ;
+ ; Exception in U mode, preempted in kernel, Intr taken (K mode), orig
+ ; task now returning to U mode (riding the Intr)
+ ; AUX_IRQ_ACTIVE won't have U bit set (since intr in K mode), hence SP
+ ; won't be switched to correct U mode value (from AUX_SP)
+ ; So force AUX_IRQ_ACT.U for such a case
+
+ btst r0, STATUS_U_BIT ; Z flag set if K (Z clear for U)
+ bset.nz r11, r11, AUX_IRQ_ACT_BIT_U ; NZ means U
+ sr r11, [AUX_IRQ_ACT]
+
+ INTERRUPT_EPILOGUE
+ rtie
+
+;####### Return from Exception / pure kernel mode #######
+
+.Lexcept_ret: ; Expects r0 has PT_status32
+
+debug_marker_syscall:
+ EXCEPTION_EPILOGUE
+ rtie
+
+;####### Return from Intr to insn in delay slot #######
+
+; Handle special case #2: (Entry via Exception in Delay Slot, Return via IRQ)
+;
+; Intr returning to a Delay Slot (DS) insn
+; (since IRQ NOT allowed in DS in ARCv2, this can only happen if orig
+; entry was via Exception in DS which got preempted in kernel).
+;
+; IRQ RTIE won't reliably restore DE bit and/or BTA, needs workaround
+;
+; Solution is to drop out of interrupt context into pure kernel mode
+; and return from pure kernel mode which does right things for delay slot
+
+.Lintr_ret_to_delay_slot:
+debug_marker_ds:
+
+ ld r2, [@intr_to_DE_cnt]
+ add r2, r2, 1
+ st r2, [@intr_to_DE_cnt]
+
+ ; drop out of interrupt context (clear AUX_IRQ_ACT.active)
+ bmskn r11, r10, 15
+ sr r11, [AUX_IRQ_ACT]
+ b .Lexcept_ret
+
+END(ret_from_exception)
diff --git a/arch/arc/kernel/entry-compact.S b/arch/arc/kernel/entry-compact.S
new file mode 100644
index 0000000000..774c03cc1d
--- /dev/null
+++ b/arch/arc/kernel/entry-compact.S
@@ -0,0 +1,388 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARCompact ISA
+ *
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * vineetg: May 2011
+ * -Userspace unaligned access emulation
+ *
+ * vineetg: Feb 2011 (ptrace low level code fixes)
+ * -traced syscall return code (r0) was not saved into pt_regs for restoring
+ * into user reg-file when traded task rets to user space.
+ * -syscalls needing arch-wrappers (mainly for passing sp as pt_regs)
+ * were not invoking post-syscall trace hook (jumping directly into
+ * ret_from_system_call)
+ *
+ * vineetg: Nov 2010:
+ * -Vector table jumps (@8 bytes) converted into branches (@4 bytes)
+ * -To maintain the slot size of 8 bytes/vector, added nop, which is
+ * not executed at runtime.
+ *
+ * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK)
+ * -do_signal()invoked upon TIF_RESTORE_SIGMASK as well
+ * -Wrappers for sys_{,rt_}sigsuspend() no longer needed as they don't
+ * need ptregs anymore
+ *
+ * Vineetg: Oct 2009
+ * -In a rare scenario, Process gets a Priv-V exception and gets scheduled
+ * out. Since we don't do FAKE RTIE for Priv-V, CPU exception state remains
+ * active (AE bit enabled). This causes a double fault for a subseq valid
+ * exception. Thus FAKE RTIE needed in low level Priv-Violation handler.
+ * Instr Error could also cause similar scenario, so same there as well.
+ *
+ * Vineetg: March 2009 (Supporting 2 levels of Interrupts)
+ *
+ * Vineetg: Aug 28th 2008: Bug #94984
+ * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap
+ * Normally CPU does this automatically, however when doing FAKE rtie,
+ * we need to explicitly do this. The problem in macros
+ * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit
+ * was being "CLEARED" rather then "SET". Since it is Loop INHIBIT Bit,
+ * setting it and not clearing it clears ZOL context
+ *
+ * Vineetg: May 16th, 2008
+ * - r25 now contains the Current Task when in kernel
+ *
+ * Vineetg: Dec 22, 2007
+ * Minor Surgery of Low Level ISR to make it SMP safe
+ * - MMU_SCRATCH0 Reg used for freeing up r9 in Level 1 ISR
+ * - _current_task is made an array of NR_CPUS
+ * - Access of _current_task wrapped inside a macro so that if hardware
+ * team agrees for a dedicated reg, no other code is touched
+ *
+ * Amit Bhor, Rahul Trivedi, Kanika Nema, Sameer Dhavale : Codito Tech 2004
+ */
+
+#include <linux/errno.h>
+#include <linux/linkage.h> /* {ENTRY,EXIT} */
+#include <asm/entry.h>
+#include <asm/irqflags.h>
+
+ .cpu A7
+
+;############################ Vector Table #################################
+
+.macro VECTOR lbl
+#if 1 /* Just in case, build breaks */
+ j \lbl
+#else
+ b \lbl
+ nop
+#endif
+.endm
+
+ .section .vector, "ax",@progbits
+ .align 4
+
+/* Each entry in the vector table must occupy 2 words. Since it is a jump
+ * across sections (.vector to .text) we are guaranteed that 'j somewhere'
+ * will use the 'j limm' form of the instruction as long as somewhere is in
+ * a section other than .vector.
+ */
+
+; ********* Critical System Events **********************
+VECTOR res_service ; 0x0, Reset Vector (0x0)
+VECTOR mem_service ; 0x8, Mem exception (0x1)
+VECTOR instr_service ; 0x10, Instrn Error (0x2)
+
+; ******************** Device ISRs **********************
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+VECTOR handle_interrupt_level2
+#else
+VECTOR handle_interrupt_level1
+#endif
+
+.rept 28
+VECTOR handle_interrupt_level1 ; Other devices
+.endr
+
+/* FOR ARC600: timer = 0x3, uart = 0x8, emac = 0x10 */
+
+; ******************** Exceptions **********************
+VECTOR EV_MachineCheck ; 0x100, Fatal Machine check (0x20)
+VECTOR EV_TLBMissI ; 0x108, Instruction TLB miss (0x21)
+VECTOR EV_TLBMissD ; 0x110, Data TLB miss (0x22)
+VECTOR EV_TLBProtV ; 0x118, Protection Violation (0x23)
+ ; or Misaligned Access
+VECTOR EV_PrivilegeV ; 0x120, Privilege Violation (0x24)
+VECTOR EV_Trap ; 0x128, Trap exception (0x25)
+VECTOR EV_Extension ; 0x130, Extn Instruction Excp (0x26)
+
+.rept 24
+VECTOR reserved ; Reserved Exceptions
+.endr
+
+
+;##################### Scratch Mem for IRQ stack switching #############
+
+ARCFP_DATA int1_saved_reg
+ .align 32
+ .type int1_saved_reg, @object
+ .size int1_saved_reg, 4
+int1_saved_reg:
+ .zero 4
+
+/* Each Interrupt level needs its own scratch */
+ARCFP_DATA int2_saved_reg
+ .type int2_saved_reg, @object
+ .size int2_saved_reg, 4
+int2_saved_reg:
+ .zero 4
+
+; ---------------------------------------------
+ .section .text, "ax",@progbits
+
+
+reserved:
+ flag 1 ; Unexpected event, halt
+
+;##################### Interrupt Handling ##############################
+
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+; ---------------------------------------------
+; Level 2 ISR: Can interrupt a Level 1 ISR
+; ---------------------------------------------
+ENTRY(handle_interrupt_level2)
+
+ INTERRUPT_PROLOGUE 2
+
+ ;------------------------------------------------------
+ ; if L2 IRQ interrupted a L1 ISR, disable preemption
+ ;
+ ; This is to avoid a potential L1-L2-L1 scenario
+ ; -L1 IRQ taken
+ ; -L2 interrupts L1 (before L1 ISR could run)
+ ; -preemption off IRQ, user task in syscall picked to run
+ ; -RTIE to userspace
+ ; Returns from L2 context fine
+ ; But both L1 and L2 re-enabled, so another L1 can be taken
+ ; while prev L1 is still unserviced
+ ;
+ ;------------------------------------------------------
+
+ ; L2 interrupting L1 implies both L2 and L1 active
+ ; However both A2 and A1 are NOT set in STATUS32, thus
+ ; need to check STATUS32_L2 to determine if L1 was active
+
+ ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs)
+ bbit0 r9, STATUS_A1_BIT, 1f ; L1 not active when L2 IRQ, so normal
+
+ ; bump thread_info->preempt_count (Disable preemption)
+ GET_CURR_THR_INFO_FROM_SP r10
+ ld r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+ add r9, r9, 1
+ st r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+
+1:
+ ;------------------------------------------------------
+ ; setup params for Linux common ISR and invoke it
+ ;------------------------------------------------------
+ lr r0, [icause2]
+ and r0, r0, 0x1f
+
+ bl.d @arch_do_IRQ
+ mov r1, sp
+
+ mov r8,0x2
+ sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg
+
+ b ret_from_exception
+
+END(handle_interrupt_level2)
+
+#endif
+
+; ---------------------------------------------
+; User Mode Memory Bus Error Interrupt Handler
+; (Kernel mode memory errors handled via separate exception vectors)
+; ---------------------------------------------
+ENTRY(mem_service)
+
+ INTERRUPT_PROLOGUE 2
+
+ mov r0, ilink2
+ mov r1, sp
+
+ ; User process needs to be killed with SIGBUS, but first need to get
+ ; out of the L2 interrupt context (drop to pure kernel mode) and jump
+ ; off to "C" code where SIGBUS in enqueued
+ lr r3, [status32]
+ bclr r3, r3, STATUS_A2_BIT
+ or r3, r3, (STATUS_E1_MASK|STATUS_E2_MASK)
+ sr r3, [status32_l2]
+ mov ilink2, 1f
+ rtie
+1:
+ bl do_memory_error
+ b ret_from_exception
+END(mem_service)
+
+; ---------------------------------------------
+; Level 1 ISR
+; ---------------------------------------------
+ENTRY(handle_interrupt_level1)
+
+ INTERRUPT_PROLOGUE 1
+
+ lr r0, [icause1]
+ and r0, r0, 0x1f
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+ ; icause1 needs to be read early, before calling tracing, which
+ ; can clobber scratch regs, hence use of stack to stash it
+ push r0
+ TRACE_ASM_IRQ_DISABLE
+ pop r0
+#endif
+
+ bl.d @arch_do_IRQ
+ mov r1, sp
+
+ mov r8,0x1
+ sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg
+
+ b ret_from_exception
+END(handle_interrupt_level1)
+
+;################### Non TLB Exception Handling #############################
+
+; ---------------------------------------------
+; Protection Violation Exception Handler
+; ---------------------------------------------
+
+ENTRY(EV_TLBProtV)
+
+ EXCEPTION_PROLOGUE ; ECR returned in r10
+
+ ;------ (5) Type of Protection Violation? ----------
+ ;
+ ; ProtV Hardware Exception is triggered for Access Faults of 2 types
+ ; -Access Violation : 00_23_(00|01|02|03)_00
+ ; x r w r+w
+ ; -Unaligned Access : 00_23_04_00
+ bbit1 r10, ECR_C_BIT_PROTV_MISALIG_DATA, 4f
+
+ ;========= (6a) Access Violation Processing ========
+ bl do_page_fault
+ b ret_from_exception
+
+ ;========== (6b) Non aligned access ============
+4:
+
+ SAVE_CALLEE_SAVED_USER
+ mov r2, sp ; callee_regs
+
+ bl do_misaligned_access
+
+ ; TBD: optimize - do this only if a callee reg was involved
+ ; either a dst of emulated LD/ST or src with address-writeback
+ RESTORE_CALLEE_SAVED_USER
+
+ b ret_from_exception
+
+END(EV_TLBProtV)
+
+; Wrapper for Linux page fault handler called from EV_TLBMiss*
+; Very similar to ProtV handler case (6a) above, but avoids the extra checks
+; for Misaligned access
+;
+ENTRY(call_do_page_fault)
+
+ EXCEPTION_PROLOGUE
+
+ mov blink, ret_from_exception
+ b do_page_fault
+
+END(call_do_page_fault)
+
+;############# Common Handlers for ARCompact and ARCv2 ##############
+
+#include "entry.S"
+
+;############# Return from Intr/Excp/Trap (ARC Specifics) ##############
+;
+; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap)
+; IRQ shd definitely not happen between now and rtie
+; All 2 entry points to here already disable interrupts
+
+.Lrestore_regs:
+
+ # Interrupts are actually disabled from this point on, but will get
+ # reenabled after we return from interrupt/exception.
+ # But irq tracer needs to be told now...
+ TRACE_ASM_IRQ_ENABLE
+
+ lr r10, [status32]
+
+ ; Restore REG File. In case multiple Events outstanding,
+ ; use the same priority as rtie: EXCPN, L2 IRQ, L1 IRQ, None
+ ; Note that we use realtime STATUS32 (not pt_regs->status32) to
+ ; decide that.
+
+ and.f 0, r10, (STATUS_A1_MASK|STATUS_A2_MASK)
+ bz .Lexcep_or_pure_K_ret
+
+ ; Returning from Interrupts (Level 1 or 2)
+
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
+
+ ; Level 2 interrupt return Path - from hardware standpoint
+ bbit0 r10, STATUS_A2_BIT, not_level2_interrupt
+
+ ;------------------------------------------------------------------
+ ; However the context returning might not have taken L2 intr itself
+ ; e.g. Task'A' user-code -> L2 intr -> schedule -> 'B' user-code ret
+ ; Special considerations needed for the context which took L2 intr
+
+ ld r9, [sp, PT_event] ; Ensure this is L2 intr context
+ brne r9, event_IRQ2, 149f
+
+ ;------------------------------------------------------------------
+ ; if L2 IRQ interrupted an L1 ISR, we'd disabled preemption earlier
+ ; so that sched doesn't move to new task, causing L1 to be delayed
+ ; undeterministically. Now that we've achieved that, let's reset
+ ; things to what they were, before returning from L2 context
+ ;----------------------------------------------------------------
+
+ ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs)
+ bbit0 r9, STATUS_A1_BIT, 149f ; L1 not active when L2 IRQ, so normal
+
+ ; decrement thread_info->preempt_count (re-enable preemption)
+ GET_CURR_THR_INFO_FROM_SP r10
+ ld r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+
+ ; paranoid check, given A1 was active when A2 happened, preempt count
+ ; must not be 0 because we would have incremented it.
+ ; If this does happen we simply HALT as it means a BUG !!!
+ cmp r9, 0
+ bnz 2f
+ flag 1
+
+2:
+ sub r9, r9, 1
+ st r9, [r10, THREAD_INFO_PREEMPT_COUNT]
+
+149:
+ INTERRUPT_EPILOGUE 2 ; return from level 2 interrupt
+debug_marker_l2:
+ rtie
+
+not_level2_interrupt:
+
+#endif
+
+ INTERRUPT_EPILOGUE 1 ; return from level 1 interrupt
+debug_marker_l1:
+ rtie
+
+.Lexcep_or_pure_K_ret:
+
+ ;this case is for syscalls or Exceptions or pure kernel mode
+
+ EXCEPTION_EPILOGUE
+debug_marker_syscall:
+ rtie
+
+END(ret_from_exception)
diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S
new file mode 100644
index 0000000000..089f668051
--- /dev/null
+++ b/arch/arc/kernel/entry.S
@@ -0,0 +1,347 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Common Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARC
+ * (included from entry-<isa>.S
+ *
+ * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+/*------------------------------------------------------------------
+ * Function ABI
+ *------------------------------------------------------------------
+ *
+ * Arguments r0 - r7
+ * Caller Saved Registers r0 - r12
+ * Callee Saved Registers r13- r25
+ * Global Pointer (gp) r26
+ * Frame Pointer (fp) r27
+ * Stack Pointer (sp) r28
+ * Branch link register (blink) r31
+ *------------------------------------------------------------------
+ */
+
+;################### Special Sys Call Wrappers ##########################
+
+ENTRY(sys_clone_wrapper)
+ SAVE_CALLEE_SAVED_USER
+ bl @sys_clone
+ DISCARD_CALLEE_SAVED_USER
+
+ GET_CURR_THR_INFO_FLAGS r10
+ and.f 0, r10, _TIF_SYSCALL_WORK
+ bnz tracesys_exit
+
+ b .Lret_from_system_call
+END(sys_clone_wrapper)
+
+ENTRY(sys_clone3_wrapper)
+ SAVE_CALLEE_SAVED_USER
+ bl @sys_clone3
+ DISCARD_CALLEE_SAVED_USER
+
+ GET_CURR_THR_INFO_FLAGS r10
+ and.f 0, r10, _TIF_SYSCALL_WORK
+ bnz tracesys_exit
+
+ b .Lret_from_system_call
+END(sys_clone3_wrapper)
+
+ENTRY(ret_from_fork)
+ ; when the forked child comes here from the __switch_to function
+ ; r0 has the last task pointer.
+ ; put last task in scheduler queue
+ jl @schedule_tail
+
+ ld r9, [sp, PT_status32]
+ brne r9, 0, 1f
+
+ jl.d [r14] ; kernel thread entry point
+ mov r0, r13 ; (see PF_KTHREAD block in copy_thread)
+
+1:
+ ; Return to user space
+ ; 1. Any forked task (Reach here via BRne above)
+ ; 2. First ever init task (Reach here via return from JL above)
+ ; This is the historic "kernel_execve" use-case, to return to init
+ ; user mode, in a round about way since that is always done from
+ ; a kernel thread which is executed via JL above but always returns
+ ; out whenever kernel_execve (now inline do_fork()) is involved
+ b ret_from_exception
+END(ret_from_fork)
+
+;################### Non TLB Exception Handling #############################
+
+; ---------------------------------------------
+; Instruction Error Exception Handler
+; ---------------------------------------------
+
+ENTRY(instr_service)
+
+ EXCEPTION_PROLOGUE
+
+ bl do_insterror_or_kprobe
+ b ret_from_exception
+END(instr_service)
+
+; ---------------------------------------------
+; Machine Check Exception Handler
+; ---------------------------------------------
+
+ENTRY(EV_MachineCheck)
+
+ EXCEPTION_PROLOGUE_KEEP_AE ; ECR returned in r10
+
+ lr r0, [efa]
+ mov r1, sp
+
+ ; MC excpetions disable MMU
+ ARC_MMU_REENABLE r3
+
+ lsr r3, r10, 8
+ bmsk r3, r3, 7
+ brne r3, ECR_C_MCHK_DUP_TLB, 1f
+
+ bl do_tlb_overlap_fault
+ b ret_from_exception
+
+1:
+ ; DEAD END: can't do much, display Regs and HALT
+ SAVE_CALLEE_SAVED_USER
+
+ GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10
+ st sp, [r10, THREAD_CALLEE_REG]
+
+ j do_machine_check_fault
+
+END(EV_MachineCheck)
+
+; ---------------------------------------------
+; Privilege Violation Exception Handler
+; ---------------------------------------------
+ENTRY(EV_PrivilegeV)
+
+ EXCEPTION_PROLOGUE
+
+ bl do_privilege_fault
+ b ret_from_exception
+END(EV_PrivilegeV)
+
+; ---------------------------------------------
+; Extension Instruction Exception Handler
+; ---------------------------------------------
+ENTRY(EV_Extension)
+
+ EXCEPTION_PROLOGUE
+
+ bl do_extension_fault
+ b ret_from_exception
+END(EV_Extension)
+
+;################ Trap Handling (Syscall, Breakpoint) ##################
+
+; ---------------------------------------------
+; syscall Tracing
+; ---------------------------------------------
+tracesys:
+ ; safekeep EFA (r12) if syscall tracer wanted PC
+ ; for traps, ERET is pre-commit so points to next-PC
+ GET_CURR_TASK_FIELD_PTR TASK_THREAD, r11
+ st r12, [r11, THREAD_FAULT_ADDR] ; thread.fault_address
+
+ ; PRE syscall trace hook
+ mov r0, sp ; pt_regs
+ bl @syscall_trace_enter
+
+ ; Tracing code now returns the syscall num (orig or modif)
+ mov r8, r0
+
+ ; Do the Sys Call as we normally would.
+ cmp r8, NR_syscalls - 1
+ mov.hi r0, -ENOSYS
+ bhi tracesys_exit
+
+ ; Restore the sys-call args. Mere invocation of the hook abv could have
+ ; clobbered them (since they are in scratch regs). The tracer could also
+ ; have deliberately changed the syscall args: r0-r7
+ ld r0, [sp, PT_r0]
+ ld r1, [sp, PT_r1]
+ ld r2, [sp, PT_r2]
+ ld r3, [sp, PT_r3]
+ ld r4, [sp, PT_r4]
+ ld r5, [sp, PT_r5]
+ ld r6, [sp, PT_r6]
+ ld r7, [sp, PT_r7]
+ ld.as r9, [sys_call_table, r8]
+ jl [r9]
+
+tracesys_exit:
+ st r0, [sp, PT_r0]
+
+ ; POST syscall trace hook
+ mov r0, sp ; pt_regs needed
+ bl @syscall_trace_exit
+
+ ; don't call ret_from_system_call as it saves r0, already done above
+ b ret_from_exception
+
+; ---------------------------------------------
+; Breakpoint TRAP
+; ---------------------------------------------
+trap_with_param:
+ mov r0, r12 ; EFA in case ptracer/gdb wants stop_pc
+ mov r1, sp ; pt_regs
+
+ ; save callee regs in case tracer/gdb wants to peek
+ SAVE_CALLEE_SAVED_USER
+
+ ; safekeep ref to callee regs
+ GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10
+ st sp, [r10, THREAD_CALLEE_REG]
+
+ ; call the non syscall trap handler
+ bl do_non_swi_trap
+
+ ; unwind stack to discard callee regs
+ DISCARD_CALLEE_SAVED_USER
+
+ b ret_from_exception
+
+; ---------------------------------------------
+; syscall TRAP
+; ABI: (r0-r7) upto 8 args, (r8) syscall number
+; ---------------------------------------------
+
+ENTRY(EV_Trap)
+
+ EXCEPTION_PROLOGUE_KEEP_AE
+
+ lr r12, [efa]
+
+ FAKE_RET_FROM_EXCPN
+
+ ;============ TRAP N : breakpoints, kprobes etc
+ bmsk.f 0, r10, 7
+ bnz trap_with_param
+
+ ;============ TRAP 0 (no param): syscall
+
+ ; syscall tracing ongoing, invoke pre-post-hooks around syscall
+ GET_CURR_THR_INFO_FLAGS r10
+ and.f 0, r10, _TIF_SYSCALL_WORK
+ bnz tracesys ; this never comes back
+
+ ;============ Normal syscall case
+
+ cmp r8, NR_syscalls - 1
+ mov.hi r0, -ENOSYS
+ bhi .Lret_from_system_call
+
+ ld.as r9,[sys_call_table, r8]
+ jl [r9]
+
+.Lret_from_system_call:
+ st r0, [sp, PT_r0] ; sys call return value in pt_regs
+
+ ; fall through to ret_from_exception
+END(EV_Trap)
+
+;############# Return from Intr/Excp/Trap (Linux Specifics) ##############
+;
+; If ret to user mode do we need to handle signals, schedule() et al.
+
+ENTRY(ret_from_exception)
+
+ ; Pre-{IRQ,Trap,Exception} K/U mode from pt_regs->status32
+ ld r8, [sp, PT_status32] ; returning to User/Kernel Mode
+
+ bbit0 r8, STATUS_U_BIT, resume_kernel_mode
+
+ ; Before returning to User mode check-for-and-complete any pending work
+ ; such as rescheduling/signal-delivery etc.
+resume_user_mode_begin:
+
+ ; Disable IRQs to ensures that chk for pending work itself is atomic
+ ; (and we don't end up missing a NEED_RESCHED/SIGPENDING due to an
+ ; interim IRQ).
+ IRQ_DISABLE r10
+
+ ; Fast Path return to user mode if no pending work
+ GET_CURR_THR_INFO_FLAGS r9
+ and.f 0, r9, _TIF_WORK_MASK
+ bz .Lrestore_regs
+
+ ; --- (Slow Path #1) task preemption ---
+ bbit0 r9, TIF_NEED_RESCHED, .Lchk_pend_signals
+ mov blink, resume_user_mode_begin ; tail-call to U mode ret chks
+ j @schedule ; BTST+Bnz causes relo error in link
+
+.Lchk_pend_signals:
+ IRQ_ENABLE r10
+
+ ; --- (Slow Path #2) pending signal ---
+ mov r0, sp ; pt_regs for arg to do_signal()/do_notify_resume()
+
+ GET_CURR_THR_INFO_FLAGS r9
+ and.f 0, r9, _TIF_SIGPENDING|_TIF_NOTIFY_SIGNAL
+ bz .Lchk_notify_resume
+
+ ; Normal Trap/IRQ entry only saves Scratch (caller-saved) regs
+ ; in pt_reg since the "C" ABI (kernel code) will automatically
+ ; save/restore callee-saved regs.
+ ;
+ ; However, here we need to explicitly save callee regs because
+ ; (i) If this signal causes coredump - full regfile needed
+ ; (ii) If signal is SIGTRAP/SIGSTOP, task is being traced thus
+ ; tracer might call PEEKUSR(CALLEE reg)
+ ;
+ ; NOTE: SP will grow up by size of CALLEE Reg-File
+ SAVE_CALLEE_SAVED_USER
+
+ ; save location of saved Callee Regs @ thread_struct->callee
+ GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10
+ st sp, [r10, THREAD_CALLEE_REG]
+
+ bl @do_signal
+
+ ; Ideally we want to discard the Callee reg above, however if this was
+ ; a tracing signal, tracer could have done a POKEUSR(CALLEE reg)
+ RESTORE_CALLEE_SAVED_USER
+
+ b resume_user_mode_begin ; loop back to start of U mode ret
+
+ ; --- (Slow Path #3) notify_resume ---
+.Lchk_notify_resume:
+ btst r9, TIF_NOTIFY_RESUME
+ blnz @do_notify_resume
+ b resume_user_mode_begin ; unconditionally back to U mode ret chks
+ ; for single exit point from this block
+
+resume_kernel_mode:
+
+ ; Disable Interrupts from this point on
+ ; CONFIG_PREEMPTION: This is a must for preempt_schedule_irq()
+ ; !CONFIG_PREEMPTION: To ensure restore_regs is intr safe
+ IRQ_DISABLE r9
+
+#ifdef CONFIG_PREEMPTION
+
+ ; Can't preempt if preemption disabled
+ GET_CURR_THR_INFO_FROM_SP r10
+ ld r8, [r10, THREAD_INFO_PREEMPT_COUNT]
+ brne r8, 0, .Lrestore_regs
+
+ ; check if this task's NEED_RESCHED flag set
+ ld r9, [r10, THREAD_INFO_FLAGS]
+ bbit0 r9, TIF_NEED_RESCHED, .Lrestore_regs
+
+ ; Invoke PREEMPTION
+ jl preempt_schedule_irq
+
+ ; preempt_schedule_irq() always returns with IRQ disabled
+#endif
+
+ b .Lrestore_regs
+
+##### DONT ADD CODE HERE - .Lrestore_regs actually follows in entry-<isa>.S
+
diff --git a/arch/arc/kernel/fpu.c b/arch/arc/kernel/fpu.c
new file mode 100644
index 0000000000..ec640219d9
--- /dev/null
+++ b/arch/arc/kernel/fpu.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * fpu.c - save/restore of Floating Point Unit Registers on task switch
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/sched.h>
+#include <asm/fpu.h>
+
+#ifdef CONFIG_ISA_ARCOMPACT
+
+/*
+ * To save/restore FPU regs, simplest scheme would use LR/SR insns.
+ * However since SR serializes the pipeline, an alternate "hack" can be used
+ * which uses the FPU Exchange insn (DEXCL) to r/w FPU regs.
+ *
+ * Store to 64bit dpfp1 reg from a pair of core regs:
+ * dexcl1 0, r1, r0 ; where r1:r0 is the 64 bit val
+ *
+ * Read from dpfp1 into pair of core regs (w/o clobbering dpfp1)
+ * mov_s r3, 0
+ * daddh11 r1, r3, r3 ; get "hi" into r1 (dpfp1 unchanged)
+ * dexcl1 r0, r1, r3 ; get "low" into r0 (dpfp1 low clobbered)
+ * dexcl1 0, r1, r0 ; restore dpfp1 to orig value
+ *
+ * However we can tweak the read, so that read-out of outgoing task's FPU regs
+ * and write of incoming task's regs happen in one shot. So all the work is
+ * done before context switch
+ */
+
+void fpu_save_restore(struct task_struct *prev, struct task_struct *next)
+{
+ unsigned int *saveto = &prev->thread.fpu.aux_dpfp[0].l;
+ unsigned int *readfrom = &next->thread.fpu.aux_dpfp[0].l;
+
+ const unsigned int zero = 0;
+
+ __asm__ __volatile__(
+ "daddh11 %0, %2, %2\n"
+ "dexcl1 %1, %3, %4\n"
+ : "=&r" (*(saveto + 1)), /* early clobber must here */
+ "=&r" (*(saveto))
+ : "r" (zero), "r" (*(readfrom + 1)), "r" (*(readfrom))
+ );
+
+ __asm__ __volatile__(
+ "daddh22 %0, %2, %2\n"
+ "dexcl2 %1, %3, %4\n"
+ : "=&r"(*(saveto + 3)), /* early clobber must here */
+ "=&r"(*(saveto + 2))
+ : "r" (zero), "r" (*(readfrom + 3)), "r" (*(readfrom + 2))
+ );
+}
+
+#else
+
+void fpu_init_task(struct pt_regs *regs)
+{
+ const unsigned int fwe = 0x80000000;
+
+ /* default rounding mode */
+ write_aux_reg(ARC_REG_FPU_CTRL, 0x100);
+
+ /* Initialize to zero: setting requires FWE be set */
+ write_aux_reg(ARC_REG_FPU_STATUS, fwe);
+}
+
+void fpu_save_restore(struct task_struct *prev, struct task_struct *next)
+{
+ struct arc_fpu *save = &prev->thread.fpu;
+ struct arc_fpu *restore = &next->thread.fpu;
+ const unsigned int fwe = 0x80000000;
+
+ save->ctrl = read_aux_reg(ARC_REG_FPU_CTRL);
+ save->status = read_aux_reg(ARC_REG_FPU_STATUS);
+
+ write_aux_reg(ARC_REG_FPU_CTRL, restore->ctrl);
+ write_aux_reg(ARC_REG_FPU_STATUS, (fwe | restore->status));
+}
+
+#endif
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
new file mode 100644
index 0000000000..9152782444
--- /dev/null
+++ b/arch/arc/kernel/head.S
@@ -0,0 +1,173 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ARC CPU startup Code
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Vineetg: Dec 2007
+ * -Check if we are running on Simulator or on real hardware
+ * to skip certain things during boot on simulator
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/entry.h>
+#include <asm/arcregs.h>
+#include <asm/cache.h>
+#include <asm/dsp-impl.h>
+#include <asm/irqflags.h>
+
+.macro CPU_EARLY_SETUP
+
+ ; Setting up Vectror Table (in case exception happens in early boot
+ sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+
+ ; Disable I-cache/D-cache if kernel so configured
+ lr r5, [ARC_REG_IC_BCR]
+ breq r5, 0, 1f ; I$ doesn't exist
+ lr r5, [ARC_REG_IC_CTRL]
+#ifdef CONFIG_ARC_HAS_ICACHE
+ bclr r5, r5, 0 ; 0 - Enable, 1 is Disable
+#else
+ bset r5, r5, 0 ; I$ exists, but is not used
+#endif
+ sr r5, [ARC_REG_IC_CTRL]
+
+1:
+ lr r5, [ARC_REG_DC_BCR]
+ breq r5, 0, 1f ; D$ doesn't exist
+ lr r5, [ARC_REG_DC_CTRL]
+ bclr r5, r5, 6 ; Invalidate (discard w/o wback)
+#ifdef CONFIG_ARC_HAS_DCACHE
+ bclr r5, r5, 0 ; Enable (+Inv)
+#else
+ bset r5, r5, 0 ; Disable (+Inv)
+#endif
+ sr r5, [ARC_REG_DC_CTRL]
+
+1:
+
+#ifdef CONFIG_ISA_ARCV2
+ ; Unaligned access is disabled at reset, so re-enable early as
+ ; gcc 7.3.1 (ARC GNU 2018.03) onwards generates unaligned access
+ ; by default
+ lr r5, [status32]
+#ifdef CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS
+ bset r5, r5, STATUS_AD_BIT
+#else
+ ; Although disabled at reset, bootloader might have enabled it
+ bclr r5, r5, STATUS_AD_BIT
+#endif
+ kflag r5
+
+#ifdef CONFIG_ARC_LPB_DISABLE
+ lr r5, [ARC_REG_LPB_BUILD]
+ breq r5, 0, 1f ; LPB doesn't exist
+ mov r5, 1
+ sr r5, [ARC_REG_LPB_CTRL]
+1:
+#endif /* CONFIG_ARC_LPB_DISABLE */
+
+ /* On HSDK, CCMs need to remapped super early */
+#ifdef CONFIG_ARC_SOC_HSDK
+ mov r6, 0x60000000
+ lr r5, [ARC_REG_ICCM_BUILD]
+ breq r5, 0, 1f
+ sr r6, [ARC_REG_AUX_ICCM]
+1:
+ lr r5, [ARC_REG_DCCM_BUILD]
+ breq r5, 0, 2f
+ sr r6, [ARC_REG_AUX_DCCM]
+2:
+#endif /* CONFIG_ARC_SOC_HSDK */
+
+#endif /* CONFIG_ISA_ARCV2 */
+
+ ; Config DSP_CTRL properly, so kernel may use integer multiply,
+ ; multiply-accumulate, and divide operations
+ DSP_EARLY_INIT
+.endm
+
+ .section .init.text, "ax",@progbits
+
+;----------------------------------------------------------------
+; Default Reset Handler (jumped into from Reset vector)
+; - Don't clobber r0,r1,r2 as they might have u-boot provided args
+; - Platforms can override this weak version if needed
+;----------------------------------------------------------------
+WEAK(res_service)
+ j stext
+END(res_service)
+
+;----------------------------------------------------------------
+; Kernel Entry point
+;----------------------------------------------------------------
+ENTRY(stext)
+
+ CPU_EARLY_SETUP
+
+#ifdef CONFIG_SMP
+ GET_CPU_ID r5
+ cmp r5, 0
+ mov.nz r0, r5
+ bz .Lmaster_proceed
+
+ ; Non-Masters wait for Master to boot enough and bring them up
+ ; when they resume, tail-call to entry point
+ mov blink, @first_lines_of_secondary
+ j arc_platform_smp_wait_to_boot
+
+.Lmaster_proceed:
+#endif
+
+ ; Clear BSS before updating any globals
+ ; XXX: use ZOL here
+ mov r5, __bss_start
+ sub r6, __bss_stop, r5
+ lsr.f lp_count, r6, 2
+ lpnz 1f
+ st.ab 0, [r5, 4]
+1:
+
+ ; Uboot - kernel ABI
+ ; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2
+ ; r1 = magic number (always zero as of now)
+ ; r2 = pointer to uboot provided cmdline or external DTB in mem
+ ; These are handled later in handle_uboot_args()
+ st r0, [@uboot_tag]
+ st r1, [@uboot_magic]
+ st r2, [@uboot_arg]
+
+ ; setup "current" tsk and optionally cache it in dedicated r25
+ mov r9, @init_task
+ SET_CURR_TASK_ON_CPU r9, r0 ; r9 = tsk, r0 = scratch
+
+ ; setup stack (fp, sp)
+ mov fp, 0
+
+ ; tsk->thread_info is really a PAGE, whose bottom hoists stack
+ GET_TSK_STACK_BASE r9, sp ; r9 = tsk, sp = stack base(output)
+
+ j start_kernel ; "C" entry point
+END(stext)
+
+#ifdef CONFIG_SMP
+;----------------------------------------------------------------
+; First lines of code run by secondary before jumping to 'C'
+;----------------------------------------------------------------
+ .section .text, "ax",@progbits
+ENTRY(first_lines_of_secondary)
+
+ ; setup per-cpu idle task as "current" on this CPU
+ ld r0, [@secondary_idle_tsk]
+ SET_CURR_TASK_ON_CPU r0, r1
+
+ ; setup stack (fp, sp)
+ mov fp, 0
+
+ ; set it's stack base to tsk->thread_info bottom
+ GET_TSK_STACK_BASE r0, sp
+
+ j start_kernel_secondary
+END(first_lines_of_secondary)
+#endif
diff --git a/arch/arc/kernel/intc-arcv2.c b/arch/arc/kernel/intc-arcv2.c
new file mode 100644
index 0000000000..678898757e
--- /dev/null
+++ b/arch/arc/kernel/intc-arcv2.c
@@ -0,0 +1,191 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2014 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
+#include <asm/irq.h>
+
+#define NR_EXCEPTIONS 16
+
+struct bcr_irq_arcv2 {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ unsigned int pad:3, firq:1, prio:4, exts:8, irqs:8, ver:8;
+#else
+ unsigned int ver:8, irqs:8, exts:8, prio:4, firq:1, pad:3;
+#endif
+};
+
+/*
+ * Early Hardware specific Interrupt setup
+ * -Called very early (start_kernel -> setup_arch -> setup_processor)
+ * -Platform Independent (must for any ARC Core)
+ * -Needed for each CPU (hence not foldable into init_IRQ)
+ */
+void arc_init_IRQ(void)
+{
+ unsigned int tmp, irq_prio, i;
+ struct bcr_irq_arcv2 irq_bcr;
+
+ struct aux_irq_ctrl {
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ unsigned int res3:18, save_idx_regs:1, res2:1,
+ save_u_to_u:1, save_lp_regs:1, save_blink:1,
+ res:4, save_nr_gpr_pairs:5;
+#else
+ unsigned int save_nr_gpr_pairs:5, res:4,
+ save_blink:1, save_lp_regs:1, save_u_to_u:1,
+ res2:1, save_idx_regs:1, res3:18;
+#endif
+ } ictrl;
+
+ *(unsigned int *)&ictrl = 0;
+
+#ifndef CONFIG_ARC_IRQ_NO_AUTOSAVE
+ ictrl.save_nr_gpr_pairs = 6; /* r0 to r11 (r12 saved manually) */
+ ictrl.save_blink = 1;
+ ictrl.save_lp_regs = 1; /* LP_COUNT, LP_START, LP_END */
+ ictrl.save_u_to_u = 0; /* user ctxt saved on kernel stack */
+ ictrl.save_idx_regs = 1; /* JLI, LDI, EI */
+#endif
+
+ WRITE_AUX(AUX_IRQ_CTRL, ictrl);
+
+ /*
+ * ARCv2 core intc provides multiple interrupt priorities (upto 16).
+ * Typical builds though have only two levels (0-high, 1-low)
+ * Linux by default uses lower prio 1 for most irqs, reserving 0 for
+ * NMI style interrupts in future (say perf)
+ */
+
+ READ_BCR(ARC_REG_IRQ_BCR, irq_bcr);
+
+ irq_prio = irq_bcr.prio; /* Encoded as N-1 for N levels */
+ pr_info("archs-intc\t: %d priority levels (default %d)%s\n",
+ irq_prio + 1, ARCV2_IRQ_DEF_PRIO,
+ irq_bcr.firq ? " FIRQ (not used)":"");
+
+ /*
+ * Set a default priority for all available interrupts to prevent
+ * switching of register banks if Fast IRQ and multiple register banks
+ * are supported by CPU.
+ * Also disable private-per-core IRQ lines so faulty external HW won't
+ * trigger interrupt that kernel is not ready to handle.
+ */
+ for (i = NR_EXCEPTIONS; i < irq_bcr.irqs + NR_EXCEPTIONS; i++) {
+ write_aux_reg(AUX_IRQ_SELECT, i);
+ write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO);
+
+ /*
+ * Only mask cpu private IRQs here.
+ * "common" interrupts are masked at IDU, otherwise it would
+ * need to be unmasked at each cpu, with IPIs
+ */
+ if (i < FIRST_EXT_IRQ)
+ write_aux_reg(AUX_IRQ_ENABLE, 0);
+ }
+
+ /* setup status32, don't enable intr yet as kernel doesn't want */
+ tmp = read_aux_reg(ARC_REG_STATUS32);
+ tmp |= ARCV2_IRQ_DEF_PRIO << 1;
+ tmp &= ~STATUS_IE_MASK;
+ asm volatile("kflag %0 \n"::"r"(tmp));
+}
+
+static void arcv2_irq_mask(struct irq_data *data)
+{
+ write_aux_reg(AUX_IRQ_SELECT, data->hwirq);
+ write_aux_reg(AUX_IRQ_ENABLE, 0);
+}
+
+static void arcv2_irq_unmask(struct irq_data *data)
+{
+ write_aux_reg(AUX_IRQ_SELECT, data->hwirq);
+ write_aux_reg(AUX_IRQ_ENABLE, 1);
+}
+
+static void arcv2_irq_enable(struct irq_data *data)
+{
+ /* set default priority */
+ write_aux_reg(AUX_IRQ_SELECT, data->hwirq);
+ write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO);
+
+ /*
+ * hw auto enables (linux unmask) all by default
+ * So no need to do IRQ_ENABLE here
+ * XXX: However OSCI LAN need it
+ */
+ write_aux_reg(AUX_IRQ_ENABLE, 1);
+}
+
+static struct irq_chip arcv2_irq_chip = {
+ .name = "ARCv2 core Intc",
+ .irq_mask = arcv2_irq_mask,
+ .irq_unmask = arcv2_irq_unmask,
+ .irq_enable = arcv2_irq_enable
+};
+
+static int arcv2_irq_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ /*
+ * core intc IRQs [16, 23]:
+ * Statically assigned always private-per-core (Timers, WDT, IPI, PCT)
+ */
+ if (hw < FIRST_EXT_IRQ) {
+ /*
+ * A subsequent request_percpu_irq() fails if percpu_devid is
+ * not set. That in turns sets NOAUTOEN, meaning each core needs
+ * to call enable_percpu_irq()
+ */
+ irq_set_percpu_devid(irq);
+ irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_percpu_irq);
+ } else {
+ irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_level_irq);
+ }
+
+ return 0;
+}
+
+static const struct irq_domain_ops arcv2_irq_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = arcv2_irq_map,
+};
+
+
+static int __init
+init_onchip_IRQ(struct device_node *intc, struct device_node *parent)
+{
+ struct irq_domain *root_domain;
+ struct bcr_irq_arcv2 irq_bcr;
+ unsigned int nr_cpu_irqs;
+
+ READ_BCR(ARC_REG_IRQ_BCR, irq_bcr);
+ nr_cpu_irqs = irq_bcr.irqs + NR_EXCEPTIONS;
+
+ if (parent)
+ panic("DeviceTree incore intc not a root irq controller\n");
+
+ root_domain = irq_domain_add_linear(intc, nr_cpu_irqs, &arcv2_irq_ops, NULL);
+ if (!root_domain)
+ panic("root irq domain not avail\n");
+
+ /*
+ * Needed for primary domain lookup to succeed
+ * This is a primary irqchip, and can never have a parent
+ */
+ irq_set_default_host(root_domain);
+
+#ifdef CONFIG_SMP
+ irq_create_mapping(root_domain, IPI_IRQ);
+#endif
+ irq_create_mapping(root_domain, SOFTIRQ_IRQ);
+
+ return 0;
+}
+
+IRQCHIP_DECLARE(arc_intc, "snps,archs-intc", init_onchip_IRQ);
diff --git a/arch/arc/kernel/intc-compact.c b/arch/arc/kernel/intc-compact.c
new file mode 100644
index 0000000000..6885e42287
--- /dev/null
+++ b/arch/arc/kernel/intc-compact.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
+#include <asm/irq.h>
+
+#define NR_CPU_IRQS 32 /* number of irq lines coming in */
+#define TIMER0_IRQ 3 /* Fixed by ISA */
+
+/*
+ * Early Hardware specific Interrupt setup
+ * -Platform independent, needed for each CPU (not foldable into init_IRQ)
+ * -Called very early (start_kernel -> setup_arch -> setup_processor)
+ *
+ * what it does ?
+ * -Optionally, setup the High priority Interrupts as Level 2 IRQs
+ */
+void arc_init_IRQ(void)
+{
+ unsigned int level_mask = 0, i;
+
+ /* Is timer high priority Interrupt (Level2 in ARCompact jargon) */
+ level_mask |= IS_ENABLED(CONFIG_ARC_COMPACT_IRQ_LEVELS) << TIMER0_IRQ;
+
+ /*
+ * Write to register, even if no LV2 IRQs configured to reset it
+ * in case bootloader had mucked with it
+ */
+ write_aux_reg(AUX_IRQ_LEV, level_mask);
+
+ if (level_mask)
+ pr_info("Level-2 interrupts bitset %x\n", level_mask);
+
+ /*
+ * Disable all IRQ lines so faulty external hardware won't
+ * trigger interrupt that kernel is not ready to handle.
+ */
+ for (i = TIMER0_IRQ; i < NR_CPU_IRQS; i++) {
+ unsigned int ienb;
+
+ ienb = read_aux_reg(AUX_IENABLE);
+ ienb &= ~(1 << i);
+ write_aux_reg(AUX_IENABLE, ienb);
+ }
+}
+
+/*
+ * ARC700 core includes a simple on-chip intc supporting
+ * -per IRQ enable/disable
+ * -2 levels of interrupts (high/low)
+ * -all interrupts being level triggered
+ *
+ * To reduce platform code, we assume all IRQs directly hooked-up into intc.
+ * Platforms with external intc, hence cascaded IRQs, are free to over-ride
+ * below, per IRQ.
+ */
+
+static void arc_irq_mask(struct irq_data *data)
+{
+ unsigned int ienb;
+
+ ienb = read_aux_reg(AUX_IENABLE);
+ ienb &= ~(1 << data->hwirq);
+ write_aux_reg(AUX_IENABLE, ienb);
+}
+
+static void arc_irq_unmask(struct irq_data *data)
+{
+ unsigned int ienb;
+
+ ienb = read_aux_reg(AUX_IENABLE);
+ ienb |= (1 << data->hwirq);
+ write_aux_reg(AUX_IENABLE, ienb);
+}
+
+static struct irq_chip onchip_intc = {
+ .name = "ARC In-core Intc",
+ .irq_mask = arc_irq_mask,
+ .irq_unmask = arc_irq_unmask,
+};
+
+static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ switch (hw) {
+ case TIMER0_IRQ:
+ irq_set_percpu_devid(irq);
+ irq_set_chip_and_handler(irq, &onchip_intc, handle_percpu_irq);
+ break;
+ default:
+ irq_set_chip_and_handler(irq, &onchip_intc, handle_level_irq);
+ }
+ return 0;
+}
+
+static const struct irq_domain_ops arc_intc_domain_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = arc_intc_domain_map,
+};
+
+static int __init
+init_onchip_IRQ(struct device_node *intc, struct device_node *parent)
+{
+ struct irq_domain *root_domain;
+
+ if (parent)
+ panic("DeviceTree incore intc not a root irq controller\n");
+
+ root_domain = irq_domain_add_linear(intc, NR_CPU_IRQS,
+ &arc_intc_domain_ops, NULL);
+ if (!root_domain)
+ panic("root irq domain not avail\n");
+
+ /*
+ * Needed for primary domain lookup to succeed
+ * This is a primary irqchip, and can never have a parent
+ */
+ irq_set_default_host(root_domain);
+
+ return 0;
+}
+
+IRQCHIP_DECLARE(arc_intc, "snps,arc700-intc", init_onchip_IRQ);
+
+/*
+ * arch_local_irq_enable - Enable interrupts.
+ *
+ * 1. Explicitly called to re-enable interrupts
+ * 2. Implicitly called from spin_unlock_irq, write_unlock_irq etc
+ * which maybe in hard ISR itself
+ *
+ * Semantics of this function change depending on where it is called from:
+ *
+ * -If called from hard-ISR, it must not invert interrupt priorities
+ * e.g. suppose TIMER is high priority (Level 2) IRQ
+ * Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times.
+ * Here local_irq_enable( ) shd not re-enable lower priority interrupts
+ * -If called from soft-ISR, it must re-enable all interrupts
+ * soft ISR are low priority jobs which can be very slow, thus all IRQs
+ * must be enabled while they run.
+ * Now hardware context wise we may still be in L2 ISR (not done rtie)
+ * still we must re-enable both L1 and L2 IRQs
+ * Another twist is prev scenario with flow being
+ * L1 ISR ==> interrupted by L2 ISR ==> L2 soft ISR
+ * here we must not re-enable Ll as prev Ll Interrupt's h/w context will get
+ * over-written (this is deficiency in ARC700 Interrupt mechanism)
+ */
+
+#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS /* Complex version for 2 IRQ levels */
+
+void arch_local_irq_enable(void)
+{
+ unsigned long flags = arch_local_save_flags();
+
+ if (flags & STATUS_A2_MASK)
+ flags |= STATUS_E2_MASK;
+ else if (flags & STATUS_A1_MASK)
+ flags |= STATUS_E1_MASK;
+
+ arch_local_irq_restore(flags);
+}
+
+EXPORT_SYMBOL(arch_local_irq_enable);
+#endif
diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
new file mode 100644
index 0000000000..dd09b58ff8
--- /dev/null
+++ b/arch/arc/kernel/irq.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irqchip.h>
+#include <asm/mach_desc.h>
+
+#include <asm/irq_regs.h>
+#include <asm/smp.h>
+
+/*
+ * Late Interrupt system init called from start_kernel for Boot CPU only
+ *
+ * Since slab must already be initialized, platforms can start doing any
+ * needed request_irq( )s
+ */
+void __init init_IRQ(void)
+{
+ /*
+ * process the entire interrupt tree in one go
+ * Any external intc will be setup provided DT chains them
+ * properly
+ */
+ irqchip_init();
+
+#ifdef CONFIG_SMP
+ /* a SMP H/w block could do IPI IRQ request here */
+ if (plat_smp_ops.init_per_cpu)
+ plat_smp_ops.init_per_cpu(smp_processor_id());
+#endif
+
+ if (machine_desc->init_per_cpu)
+ machine_desc->init_per_cpu(smp_processor_id());
+}
+
+/*
+ * "C" Entry point for any ARC ISR, called from low level vector handler
+ * @irq is the vector number read from ICAUSE reg of on-chip intc
+ */
+void arch_do_IRQ(unsigned int hwirq, struct pt_regs *regs)
+{
+ struct pt_regs *old_regs;
+
+ irq_enter();
+ old_regs = set_irq_regs(regs);
+ generic_handle_domain_irq(NULL, hwirq);
+ set_irq_regs(old_regs);
+ irq_exit();
+}
diff --git a/arch/arc/kernel/jump_label.c b/arch/arc/kernel/jump_label.c
new file mode 100644
index 0000000000..70b74a5d04
--- /dev/null
+++ b/arch/arc/kernel/jump_label.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kernel.h>
+#include <linux/jump_label.h>
+
+#include "asm/cacheflush.h"
+
+#define JUMPLABEL_ERR "ARC: jump_label: ERROR: "
+
+/* Halt system on fatal error to make debug easier */
+#define arc_jl_fatal(format...) \
+({ \
+ pr_err(JUMPLABEL_ERR format); \
+ BUG(); \
+})
+
+static inline u32 arc_gen_nop(void)
+{
+ /* 1x 32bit NOP in middle endian */
+ return 0x7000264a;
+}
+
+/*
+ * Atomic update of patched instruction is only available if this
+ * instruction doesn't cross L1 cache line boundary. You can read about
+ * the way we achieve this in arc/include/asm/jump_label.h
+ */
+static inline void instruction_align_assert(void *addr, int len)
+{
+ unsigned long a = (unsigned long)addr;
+
+ if ((a >> L1_CACHE_SHIFT) != ((a + len - 1) >> L1_CACHE_SHIFT))
+ arc_jl_fatal("instruction (addr %px) cross L1 cache line border",
+ addr);
+}
+
+/*
+ * ARCv2 'Branch unconditionally' instruction:
+ * 00000ssssssssss1SSSSSSSSSSNRtttt
+ * s S[n:0] lower bits signed immediate (number is bitfield size)
+ * S S[m:n+1] upper bits signed immediate (number is bitfield size)
+ * t S[24:21] upper bits signed immediate (branch unconditionally far)
+ * N N <.d> delay slot mode
+ * R R Reserved
+ */
+static inline u32 arc_gen_branch(jump_label_t pc, jump_label_t target)
+{
+ u32 instruction_l, instruction_r;
+ u32 pcl = pc & GENMASK(31, 2);
+ u32 u_offset = target - pcl;
+ u32 s, S, t;
+
+ /*
+ * Offset in 32-bit branch instruction must to fit into s25.
+ * Something is terribly broken if we get such huge offset within one
+ * function.
+ */
+ if ((s32)u_offset < -16777216 || (s32)u_offset > 16777214)
+ arc_jl_fatal("gen branch with offset (%d) not fit in s25",
+ (s32)u_offset);
+
+ /*
+ * All instructions are aligned by 2 bytes so we should never get offset
+ * here which is not 2 bytes aligned.
+ */
+ if (u_offset & 0x1)
+ arc_jl_fatal("gen branch with offset (%d) unaligned to 2 bytes",
+ (s32)u_offset);
+
+ s = (u_offset >> 1) & GENMASK(9, 0);
+ S = (u_offset >> 11) & GENMASK(9, 0);
+ t = (u_offset >> 21) & GENMASK(3, 0);
+
+ /* 00000ssssssssss1 */
+ instruction_l = (s << 1) | 0x1;
+ /* SSSSSSSSSSNRtttt */
+ instruction_r = (S << 6) | t;
+
+ return (instruction_r << 16) | (instruction_l & GENMASK(15, 0));
+}
+
+void arch_jump_label_transform(struct jump_entry *entry,
+ enum jump_label_type type)
+{
+ jump_label_t *instr_addr = (jump_label_t *)entry->code;
+ u32 instr;
+
+ instruction_align_assert(instr_addr, JUMP_LABEL_NOP_SIZE);
+
+ if (type == JUMP_LABEL_JMP)
+ instr = arc_gen_branch(entry->code, entry->target);
+ else
+ instr = arc_gen_nop();
+
+ WRITE_ONCE(*instr_addr, instr);
+ flush_icache_range(entry->code, entry->code + JUMP_LABEL_NOP_SIZE);
+}
+
+#ifdef CONFIG_ARC_DBG_JUMP_LABEL
+#define SELFTEST_MSG "ARC: instruction generation self-test: "
+
+struct arc_gen_branch_testdata {
+ jump_label_t pc;
+ jump_label_t target_address;
+ u32 expected_instr;
+};
+
+static __init int branch_gen_test(const struct arc_gen_branch_testdata *test)
+{
+ u32 instr_got;
+
+ instr_got = arc_gen_branch(test->pc, test->target_address);
+ if (instr_got == test->expected_instr)
+ return 0;
+
+ pr_err(SELFTEST_MSG "FAIL:\n arc_gen_branch(0x%08x, 0x%08x) != 0x%08x, got 0x%08x\n",
+ test->pc, test->target_address,
+ test->expected_instr, instr_got);
+
+ return -EFAULT;
+}
+
+/*
+ * Offset field in branch instruction is not continuous. Test all
+ * available offset field and sign combinations. Test data is generated
+ * from real working code.
+ */
+static const struct arc_gen_branch_testdata arcgenbr_test_data[] __initconst = {
+ {0x90007548, 0x90007514, 0xffcf07cd}, /* tiny (-52) offs */
+ {0x9000c9c0, 0x9000c782, 0xffcf05c3}, /* tiny (-574) offs */
+ {0x9000cc1c, 0x9000c782, 0xffcf0367}, /* tiny (-1178) offs */
+ {0x9009dce0, 0x9009d106, 0xff8f0427}, /* small (-3034) offs */
+ {0x9000f5de, 0x90007d30, 0xfc0f0755}, /* big (-30892) offs */
+ {0x900a2444, 0x90035f64, 0xc9cf0321}, /* huge (-443616) offs */
+ {0x90007514, 0x9000752c, 0x00000019}, /* tiny (+24) offs */
+ {0x9001a578, 0x9001a77a, 0x00000203}, /* tiny (+514) offs */
+ {0x90031ed8, 0x90032634, 0x0000075d}, /* tiny (+1884) offs */
+ {0x9008c7f2, 0x9008d3f0, 0x00400401}, /* small (+3072) offs */
+ {0x9000bb38, 0x9003b340, 0x17c00009}, /* big (+194568) offs */
+ {0x90008f44, 0x90578d80, 0xb7c2063d} /* huge (+5701180) offs */
+};
+
+static __init int instr_gen_test(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(arcgenbr_test_data); i++)
+ if (branch_gen_test(&arcgenbr_test_data[i]))
+ return -EFAULT;
+
+ pr_info(SELFTEST_MSG "OK\n");
+
+ return 0;
+}
+early_initcall(instr_gen_test);
+
+#endif /* CONFIG_ARC_DBG_JUMP_LABEL */
diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c
new file mode 100644
index 0000000000..4f2b595145
--- /dev/null
+++ b/arch/arc/kernel/kgdb.c
@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * kgdb support for ARC
+ *
+ * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/kgdb.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <asm/disasm.h>
+#include <asm/cacheflush.h>
+
+static void to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs,
+ struct callee_regs *cregs)
+{
+ int regno;
+
+ for (regno = 0; regno <= 26; regno++)
+ gdb_regs[_R0 + regno] = get_reg(regno, kernel_regs, cregs);
+
+ for (regno = 27; regno < GDB_MAX_REGS; regno++)
+ gdb_regs[regno] = 0;
+
+ gdb_regs[_FP] = kernel_regs->fp;
+ gdb_regs[__SP] = kernel_regs->sp;
+ gdb_regs[_BLINK] = kernel_regs->blink;
+ gdb_regs[_RET] = kernel_regs->ret;
+ gdb_regs[_STATUS32] = kernel_regs->status32;
+ gdb_regs[_LP_COUNT] = kernel_regs->lp_count;
+ gdb_regs[_LP_END] = kernel_regs->lp_end;
+ gdb_regs[_LP_START] = kernel_regs->lp_start;
+ gdb_regs[_BTA] = kernel_regs->bta;
+ gdb_regs[_STOP_PC] = kernel_regs->ret;
+}
+
+static void from_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs,
+ struct callee_regs *cregs)
+{
+ int regno;
+
+ for (regno = 0; regno <= 26; regno++)
+ set_reg(regno, gdb_regs[regno + _R0], kernel_regs, cregs);
+
+ kernel_regs->fp = gdb_regs[_FP];
+ kernel_regs->sp = gdb_regs[__SP];
+ kernel_regs->blink = gdb_regs[_BLINK];
+ kernel_regs->ret = gdb_regs[_RET];
+ kernel_regs->status32 = gdb_regs[_STATUS32];
+ kernel_regs->lp_count = gdb_regs[_LP_COUNT];
+ kernel_regs->lp_end = gdb_regs[_LP_END];
+ kernel_regs->lp_start = gdb_regs[_LP_START];
+ kernel_regs->bta = gdb_regs[_BTA];
+}
+
+
+void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
+{
+ to_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *)
+ current->thread.callee_reg);
+}
+
+void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs)
+{
+ from_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *)
+ current->thread.callee_reg);
+}
+
+void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs,
+ struct task_struct *task)
+{
+ if (task)
+ to_gdb_regs(gdb_regs, task_pt_regs(task),
+ (struct callee_regs *) task->thread.callee_reg);
+}
+
+struct single_step_data_t {
+ uint16_t opcode[2];
+ unsigned long address[2];
+ int is_branch;
+ int armed;
+} single_step_data;
+
+static void undo_single_step(struct pt_regs *regs)
+{
+ if (single_step_data.armed) {
+ int i;
+
+ for (i = 0; i < (single_step_data.is_branch ? 2 : 1); i++) {
+ memcpy((void *) single_step_data.address[i],
+ &single_step_data.opcode[i],
+ BREAK_INSTR_SIZE);
+
+ flush_icache_range(single_step_data.address[i],
+ single_step_data.address[i] +
+ BREAK_INSTR_SIZE);
+ }
+ single_step_data.armed = 0;
+ }
+}
+
+static void place_trap(unsigned long address, void *save)
+{
+ memcpy(save, (void *) address, BREAK_INSTR_SIZE);
+ memcpy((void *) address, &arch_kgdb_ops.gdb_bpt_instr,
+ BREAK_INSTR_SIZE);
+ flush_icache_range(address, address + BREAK_INSTR_SIZE);
+}
+
+static void do_single_step(struct pt_regs *regs)
+{
+ single_step_data.is_branch = disasm_next_pc((unsigned long)
+ regs->ret, regs, (struct callee_regs *)
+ current->thread.callee_reg,
+ &single_step_data.address[0],
+ &single_step_data.address[1]);
+
+ place_trap(single_step_data.address[0], &single_step_data.opcode[0]);
+
+ if (single_step_data.is_branch) {
+ place_trap(single_step_data.address[1],
+ &single_step_data.opcode[1]);
+ }
+
+ single_step_data.armed++;
+}
+
+int kgdb_arch_handle_exception(int e_vector, int signo, int err_code,
+ char *remcomInBuffer, char *remcomOutBuffer,
+ struct pt_regs *regs)
+{
+ unsigned long addr;
+ char *ptr;
+
+ undo_single_step(regs);
+
+ switch (remcomInBuffer[0]) {
+ case 's':
+ case 'c':
+ ptr = &remcomInBuffer[1];
+ if (kgdb_hex2long(&ptr, &addr))
+ regs->ret = addr;
+ fallthrough;
+
+ case 'D':
+ case 'k':
+ atomic_set(&kgdb_cpu_doing_single_step, -1);
+
+ if (remcomInBuffer[0] == 's') {
+ do_single_step(regs);
+ atomic_set(&kgdb_cpu_doing_single_step,
+ smp_processor_id());
+ }
+
+ return 0;
+ }
+ return -1;
+}
+
+int kgdb_arch_init(void)
+{
+ single_step_data.armed = 0;
+ return 0;
+}
+
+void kgdb_trap(struct pt_regs *regs)
+{
+ /* trap_s 3 is used for breakpoints that overwrite existing
+ * instructions, while trap_s 4 is used for compiled breakpoints.
+ *
+ * with trap_s 3 breakpoints the original instruction needs to be
+ * restored and continuation needs to start at the location of the
+ * breakpoint.
+ *
+ * with trap_s 4 (compiled) breakpoints, continuation needs to
+ * start after the breakpoint.
+ */
+ if (regs->ecr.param == 3)
+ instruction_pointer(regs) -= BREAK_INSTR_SIZE;
+
+ kgdb_handle_exception(1, SIGTRAP, 0, regs);
+}
+
+void kgdb_arch_exit(void)
+{
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+ instruction_pointer(regs) = ip;
+}
+
+void kgdb_call_nmi_hook(void *ignored)
+{
+ /* Default implementation passes get_irq_regs() but we don't */
+ kgdb_nmicallback(raw_smp_processor_id(), NULL);
+}
+
+const struct kgdb_arch arch_kgdb_ops = {
+ /* breakpoint instruction: TRAP_S 0x3 */
+#ifdef CONFIG_CPU_BIG_ENDIAN
+ .gdb_bpt_instr = {0x78, 0x7e},
+#else
+ .gdb_bpt_instr = {0x7e, 0x78},
+#endif
+};
diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c
new file mode 100644
index 0000000000..e71d64119d
--- /dev/null
+++ b/arch/arc/kernel/kprobes.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/types.h>
+#include <linux/kprobes.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kdebug.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <asm/cacheflush.h>
+#include <asm/current.h>
+#include <asm/disasm.h>
+
+#define MIN_STACK_SIZE(addr) min((unsigned long)MAX_STACK_SIZE, \
+ (unsigned long)current_thread_info() + THREAD_SIZE - (addr))
+
+DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
+DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
+
+int __kprobes arch_prepare_kprobe(struct kprobe *p)
+{
+ /* Attempt to probe at unaligned address */
+ if ((unsigned long)p->addr & 0x01)
+ return -EINVAL;
+
+ /* Address should not be in exception handling code */
+
+ p->ainsn.is_short = is_short_instr((unsigned long)p->addr);
+ p->opcode = *p->addr;
+
+ return 0;
+}
+
+void __kprobes arch_arm_kprobe(struct kprobe *p)
+{
+ *p->addr = UNIMP_S_INSTRUCTION;
+
+ flush_icache_range((unsigned long)p->addr,
+ (unsigned long)p->addr + sizeof(kprobe_opcode_t));
+}
+
+void __kprobes arch_disarm_kprobe(struct kprobe *p)
+{
+ *p->addr = p->opcode;
+
+ flush_icache_range((unsigned long)p->addr,
+ (unsigned long)p->addr + sizeof(kprobe_opcode_t));
+}
+
+void __kprobes arch_remove_kprobe(struct kprobe *p)
+{
+ arch_disarm_kprobe(p);
+
+ /* Can we remove the kprobe in the middle of kprobe handling? */
+ if (p->ainsn.t1_addr) {
+ *(p->ainsn.t1_addr) = p->ainsn.t1_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t1_addr,
+ (unsigned long)p->ainsn.t1_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t1_addr = NULL;
+ }
+
+ if (p->ainsn.t2_addr) {
+ *(p->ainsn.t2_addr) = p->ainsn.t2_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t2_addr,
+ (unsigned long)p->ainsn.t2_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t2_addr = NULL;
+ }
+}
+
+static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
+{
+ kcb->prev_kprobe.kp = kprobe_running();
+ kcb->prev_kprobe.status = kcb->kprobe_status;
+}
+
+static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
+{
+ __this_cpu_write(current_kprobe, kcb->prev_kprobe.kp);
+ kcb->kprobe_status = kcb->prev_kprobe.status;
+}
+
+static inline void __kprobes set_current_kprobe(struct kprobe *p)
+{
+ __this_cpu_write(current_kprobe, p);
+}
+
+static void __kprobes resume_execution(struct kprobe *p, unsigned long addr,
+ struct pt_regs *regs)
+{
+ /* Remove the trap instructions inserted for single step and
+ * restore the original instructions
+ */
+ if (p->ainsn.t1_addr) {
+ *(p->ainsn.t1_addr) = p->ainsn.t1_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t1_addr,
+ (unsigned long)p->ainsn.t1_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t1_addr = NULL;
+ }
+
+ if (p->ainsn.t2_addr) {
+ *(p->ainsn.t2_addr) = p->ainsn.t2_opcode;
+
+ flush_icache_range((unsigned long)p->ainsn.t2_addr,
+ (unsigned long)p->ainsn.t2_addr +
+ sizeof(kprobe_opcode_t));
+
+ p->ainsn.t2_addr = NULL;
+ }
+
+ return;
+}
+
+static void __kprobes setup_singlestep(struct kprobe *p, struct pt_regs *regs)
+{
+ unsigned long next_pc;
+ unsigned long tgt_if_br = 0;
+ int is_branch;
+ unsigned long bta;
+
+ /* Copy the opcode back to the kprobe location and execute the
+ * instruction. Because of this we will not be able to get into the
+ * same kprobe until this kprobe is done
+ */
+ *(p->addr) = p->opcode;
+
+ flush_icache_range((unsigned long)p->addr,
+ (unsigned long)p->addr + sizeof(kprobe_opcode_t));
+
+ /* Now we insert the trap at the next location after this instruction to
+ * single step. If it is a branch we insert the trap at possible branch
+ * targets
+ */
+
+ bta = regs->bta;
+
+ if (regs->status32 & 0x40) {
+ /* We are in a delay slot with the branch taken */
+
+ next_pc = bta & ~0x01;
+
+ if (!p->ainsn.is_short) {
+ if (bta & 0x01)
+ regs->blink += 2;
+ else {
+ /* Branch not taken */
+ next_pc += 2;
+
+ /* next pc is taken from bta after executing the
+ * delay slot instruction
+ */
+ regs->bta += 2;
+ }
+ }
+
+ is_branch = 0;
+ } else
+ is_branch =
+ disasm_next_pc((unsigned long)p->addr, regs,
+ (struct callee_regs *) current->thread.callee_reg,
+ &next_pc, &tgt_if_br);
+
+ p->ainsn.t1_addr = (kprobe_opcode_t *) next_pc;
+ p->ainsn.t1_opcode = *(p->ainsn.t1_addr);
+ *(p->ainsn.t1_addr) = TRAP_S_2_INSTRUCTION;
+
+ flush_icache_range((unsigned long)p->ainsn.t1_addr,
+ (unsigned long)p->ainsn.t1_addr +
+ sizeof(kprobe_opcode_t));
+
+ if (is_branch) {
+ p->ainsn.t2_addr = (kprobe_opcode_t *) tgt_if_br;
+ p->ainsn.t2_opcode = *(p->ainsn.t2_addr);
+ *(p->ainsn.t2_addr) = TRAP_S_2_INSTRUCTION;
+
+ flush_icache_range((unsigned long)p->ainsn.t2_addr,
+ (unsigned long)p->ainsn.t2_addr +
+ sizeof(kprobe_opcode_t));
+ }
+}
+
+int __kprobes arc_kprobe_handler(unsigned long addr, struct pt_regs *regs)
+{
+ struct kprobe *p;
+ struct kprobe_ctlblk *kcb;
+
+ preempt_disable();
+
+ kcb = get_kprobe_ctlblk();
+ p = get_kprobe((unsigned long *)addr);
+
+ if (p) {
+ /*
+ * We have reentered the kprobe_handler, since another kprobe
+ * was hit while within the handler, we save the original
+ * kprobes and single step on the instruction of the new probe
+ * without calling any user handlers to avoid recursive
+ * kprobes.
+ */
+ if (kprobe_running()) {
+ save_previous_kprobe(kcb);
+ set_current_kprobe(p);
+ kprobes_inc_nmissed_count(p);
+ setup_singlestep(p, regs);
+ kcb->kprobe_status = KPROBE_REENTER;
+ return 1;
+ }
+
+ set_current_kprobe(p);
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+
+ /* If we have no pre-handler or it returned 0, we continue with
+ * normal processing. If we have a pre-handler and it returned
+ * non-zero - which means user handler setup registers to exit
+ * to another instruction, we must skip the single stepping.
+ */
+ if (!p->pre_handler || !p->pre_handler(p, regs)) {
+ setup_singlestep(p, regs);
+ kcb->kprobe_status = KPROBE_HIT_SS;
+ } else {
+ reset_current_kprobe();
+ preempt_enable_no_resched();
+ }
+
+ return 1;
+ }
+
+ /* no_kprobe: */
+ preempt_enable_no_resched();
+ return 0;
+}
+
+static int __kprobes arc_post_kprobe_handler(unsigned long addr,
+ struct pt_regs *regs)
+{
+ struct kprobe *cur = kprobe_running();
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ if (!cur)
+ return 0;
+
+ resume_execution(cur, addr, regs);
+
+ /* Rearm the kprobe */
+ arch_arm_kprobe(cur);
+
+ /*
+ * When we return from trap instruction we go to the next instruction
+ * We restored the actual instruction in resume_exectuiont and we to
+ * return to the same address and execute it
+ */
+ regs->ret = addr;
+
+ if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
+ kcb->kprobe_status = KPROBE_HIT_SSDONE;
+ cur->post_handler(cur, regs, 0);
+ }
+
+ if (kcb->kprobe_status == KPROBE_REENTER) {
+ restore_previous_kprobe(kcb);
+ goto out;
+ }
+
+ reset_current_kprobe();
+
+out:
+ preempt_enable_no_resched();
+ return 1;
+}
+
+/*
+ * Fault can be for the instruction being single stepped or for the
+ * pre/post handlers in the module.
+ * This is applicable for applications like user probes, where we have the
+ * probe in user space and the handlers in the kernel
+ */
+
+int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned long trapnr)
+{
+ struct kprobe *cur = kprobe_running();
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ switch (kcb->kprobe_status) {
+ case KPROBE_HIT_SS:
+ case KPROBE_REENTER:
+ /*
+ * We are here because the instruction being single stepped
+ * caused the fault. We reset the current kprobe and allow the
+ * exception handler as if it is regular exception. In our
+ * case it doesn't matter because the system will be halted
+ */
+ resume_execution(cur, (unsigned long)cur->addr, regs);
+
+ if (kcb->kprobe_status == KPROBE_REENTER)
+ restore_previous_kprobe(kcb);
+ else
+ reset_current_kprobe();
+
+ preempt_enable_no_resched();
+ break;
+
+ case KPROBE_HIT_ACTIVE:
+ case KPROBE_HIT_SSDONE:
+ /*
+ * We are here because the instructions in the pre/post handler
+ * caused the fault.
+ */
+
+ /*
+ * In case the user-specified fault handler returned zero,
+ * try to fix up.
+ */
+ if (fixup_exception(regs))
+ return 1;
+
+ /*
+ * fixup_exception() could not handle it,
+ * Let do_page_fault() fix it.
+ */
+ break;
+
+ default:
+ break;
+ }
+ return 0;
+}
+
+int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct die_args *args = data;
+ unsigned long addr = args->err;
+ int ret = NOTIFY_DONE;
+
+ switch (val) {
+ case DIE_IERR:
+ if (arc_kprobe_handler(addr, args->regs))
+ return NOTIFY_STOP;
+ break;
+
+ case DIE_TRAP:
+ if (arc_post_kprobe_handler(addr, args->regs))
+ return NOTIFY_STOP;
+ break;
+
+ default:
+ break;
+ }
+
+ return ret;
+}
+
+static void __used kretprobe_trampoline_holder(void)
+{
+ __asm__ __volatile__(".global __kretprobe_trampoline\n"
+ "__kretprobe_trampoline:\n"
+ "nop\n");
+}
+
+void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri,
+ struct pt_regs *regs)
+{
+
+ ri->ret_addr = (kprobe_opcode_t *) regs->blink;
+ ri->fp = NULL;
+
+ /* Replace the return addr with trampoline addr */
+ regs->blink = (unsigned long)&__kretprobe_trampoline;
+}
+
+static int __kprobes trampoline_probe_handler(struct kprobe *p,
+ struct pt_regs *regs)
+{
+ regs->ret = __kretprobe_trampoline_handler(regs, NULL);
+
+ /* By returning a non zero value, we are telling the kprobe handler
+ * that we don't want the post_handler to run
+ */
+ return 1;
+}
+
+static struct kprobe trampoline_p = {
+ .addr = (kprobe_opcode_t *) &__kretprobe_trampoline,
+ .pre_handler = trampoline_probe_handler
+};
+
+int __init arch_init_kprobes(void)
+{
+ /* Registering the trampoline code for the kret probe */
+ return register_kprobe(&trampoline_p);
+}
+
+int __kprobes arch_trampoline_kprobe(struct kprobe *p)
+{
+ if (p->addr == (kprobe_opcode_t *) &__kretprobe_trampoline)
+ return 1;
+
+ return 0;
+}
+
+void trap_is_kprobe(unsigned long address, struct pt_regs *regs)
+{
+ notify_die(DIE_TRAP, "kprobe_trap", regs, address, 0, SIGTRAP);
+}
diff --git a/arch/arc/kernel/mcip.c b/arch/arc/kernel/mcip.c
new file mode 100644
index 0000000000..55373ca0d2
--- /dev/null
+++ b/arch/arc/kernel/mcip.c
@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ARC ARConnect (MultiCore IP) support (formerly known as MCIP)
+ *
+ * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/smp.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/spinlock.h>
+#include <soc/arc/mcip.h>
+#include <asm/irqflags-arcv2.h>
+#include <asm/setup.h>
+
+static DEFINE_RAW_SPINLOCK(mcip_lock);
+
+#ifdef CONFIG_SMP
+
+static char smp_cpuinfo_buf[128];
+
+/*
+ * Set mask to halt GFRC if any online core in SMP cluster is halted.
+ * Only works for ARC HS v3.0+, on earlier versions has no effect.
+ */
+static void mcip_update_gfrc_halt_mask(int cpu)
+{
+ struct bcr_generic gfrc;
+ unsigned long flags;
+ u32 gfrc_halt_mask;
+
+ READ_BCR(ARC_REG_GFRC_BUILD, gfrc);
+
+ /*
+ * CMD_GFRC_SET_CORE and CMD_GFRC_READ_CORE commands were added in
+ * GFRC 0x3 version.
+ */
+ if (gfrc.ver < 0x3)
+ return;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ __mcip_cmd(CMD_GFRC_READ_CORE, 0);
+ gfrc_halt_mask = read_aux_reg(ARC_REG_MCIP_READBACK);
+ gfrc_halt_mask |= BIT(cpu);
+ __mcip_cmd_data(CMD_GFRC_SET_CORE, 0, gfrc_halt_mask);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_update_debug_halt_mask(int cpu)
+{
+ u32 mcip_mask = 0;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ /*
+ * mcip_mask is same for CMD_DEBUG_SET_SELECT and CMD_DEBUG_SET_MASK
+ * commands. So read it once instead of reading both CMD_DEBUG_READ_MASK
+ * and CMD_DEBUG_READ_SELECT.
+ */
+ __mcip_cmd(CMD_DEBUG_READ_SELECT, 0);
+ mcip_mask = read_aux_reg(ARC_REG_MCIP_READBACK);
+
+ mcip_mask |= BIT(cpu);
+
+ __mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, mcip_mask);
+ /*
+ * Parameter specified halt cause:
+ * STATUS32[H]/actionpoint/breakpoint/self-halt
+ * We choose all of them (0xF).
+ */
+ __mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xF, mcip_mask);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_setup_per_cpu(int cpu)
+{
+ struct mcip_bcr mp;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+
+ smp_ipi_irq_setup(cpu, IPI_IRQ);
+ smp_ipi_irq_setup(cpu, SOFTIRQ_IRQ);
+
+ /* Update GFRC halt mask as new CPU came online */
+ if (mp.gfrc)
+ mcip_update_gfrc_halt_mask(cpu);
+
+ /* Update MCIP debug mask as new CPU came online */
+ if (mp.dbg)
+ mcip_update_debug_halt_mask(cpu);
+}
+
+static void mcip_ipi_send(int cpu)
+{
+ unsigned long flags;
+ int ipi_was_pending;
+
+ /* ARConnect can only send IPI to others */
+ if (unlikely(cpu == raw_smp_processor_id())) {
+ arc_softirq_trigger(SOFTIRQ_IRQ);
+ return;
+ }
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ /*
+ * If receiver already has a pending interrupt, elide sending this one.
+ * Linux cross core calling works well with concurrent IPIs
+ * coalesced into one
+ * see arch/arc/kernel/smp.c: ipi_send_msg_one()
+ */
+ __mcip_cmd(CMD_INTRPT_READ_STATUS, cpu);
+ ipi_was_pending = read_aux_reg(ARC_REG_MCIP_READBACK);
+ if (!ipi_was_pending)
+ __mcip_cmd(CMD_INTRPT_GENERATE_IRQ, cpu);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_ipi_clear(int irq)
+{
+ unsigned int cpu, c;
+ unsigned long flags;
+
+ if (unlikely(irq == SOFTIRQ_IRQ)) {
+ arc_softirq_clear(irq);
+ return;
+ }
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ /* Who sent the IPI */
+ __mcip_cmd(CMD_INTRPT_CHECK_SOURCE, 0);
+
+ cpu = read_aux_reg(ARC_REG_MCIP_READBACK); /* 1,2,4,8... */
+
+ /*
+ * In rare case, multiple concurrent IPIs sent to same target can
+ * possibly be coalesced by MCIP into 1 asserted IRQ, so @cpus can be
+ * "vectored" (multiple bits sets) as opposed to typical single bit
+ */
+ do {
+ c = __ffs(cpu); /* 0,1,2,3 */
+ __mcip_cmd(CMD_INTRPT_GENERATE_ACK, c);
+ cpu &= ~(1U << c);
+ } while (cpu);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void mcip_probe_n_setup(void)
+{
+ struct mcip_bcr mp;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+
+ sprintf(smp_cpuinfo_buf,
+ "Extn [SMP]\t: ARConnect (v%d): %d cores with %s%s%s%s\n",
+ mp.ver, mp.num_cores,
+ IS_AVAIL1(mp.ipi, "IPI "),
+ IS_AVAIL1(mp.idu, "IDU "),
+ IS_AVAIL1(mp.dbg, "DEBUG "),
+ IS_AVAIL1(mp.gfrc, "GFRC"));
+}
+
+struct plat_smp_ops plat_smp_ops = {
+ .info = smp_cpuinfo_buf,
+ .init_early_smp = mcip_probe_n_setup,
+ .init_per_cpu = mcip_setup_per_cpu,
+ .ipi_send = mcip_ipi_send,
+ .ipi_clear = mcip_ipi_clear,
+};
+
+#endif
+
+/***************************************************************************
+ * ARCv2 Interrupt Distribution Unit (IDU)
+ *
+ * Connects external "COMMON" IRQs to core intc, providing:
+ * -dynamic routing (IRQ affinity)
+ * -load balancing (Round Robin interrupt distribution)
+ * -1:N distribution
+ *
+ * It physically resides in the MCIP hw block
+ */
+
+#include <linux/irqchip.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+
+/*
+ * Set the DEST for @cmn_irq to @cpu_mask (1 bit per core)
+ */
+static void idu_set_dest(unsigned int cmn_irq, unsigned int cpu_mask)
+{
+ __mcip_cmd_data(CMD_IDU_SET_DEST, cmn_irq, cpu_mask);
+}
+
+static void idu_set_mode(unsigned int cmn_irq, bool set_lvl, unsigned int lvl,
+ bool set_distr, unsigned int distr)
+{
+ union {
+ unsigned int word;
+ struct {
+ unsigned int distr:2, pad:2, lvl:1, pad2:27;
+ };
+ } data;
+
+ data.word = __mcip_cmd_read(CMD_IDU_READ_MODE, cmn_irq);
+ if (set_distr)
+ data.distr = distr;
+ if (set_lvl)
+ data.lvl = lvl;
+ __mcip_cmd_data(CMD_IDU_SET_MODE, cmn_irq, data.word);
+}
+
+static void idu_irq_mask_raw(irq_hw_number_t hwirq)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd_data(CMD_IDU_SET_MASK, hwirq, 1);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void idu_irq_mask(struct irq_data *data)
+{
+ idu_irq_mask_raw(data->hwirq);
+}
+
+static void idu_irq_unmask(struct irq_data *data)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 0);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void idu_irq_ack(struct irq_data *data)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static void idu_irq_mask_ack(struct irq_data *data)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+ __mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 1);
+ __mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq);
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+}
+
+static int
+idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask,
+ bool force)
+{
+ unsigned long flags;
+ cpumask_t online;
+ unsigned int destination_bits;
+ unsigned int distribution_mode;
+
+ /* errout if no online cpu per @cpumask */
+ if (!cpumask_and(&online, cpumask, cpu_online_mask))
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ destination_bits = cpumask_bits(&online)[0];
+ idu_set_dest(data->hwirq, destination_bits);
+
+ if (ffs(destination_bits) == fls(destination_bits))
+ distribution_mode = IDU_M_DISTRI_DEST;
+ else
+ distribution_mode = IDU_M_DISTRI_RR;
+
+ idu_set_mode(data->hwirq, false, 0, true, distribution_mode);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+
+ return IRQ_SET_MASK_OK;
+}
+
+static int idu_irq_set_type(struct irq_data *data, u32 type)
+{
+ unsigned long flags;
+
+ /*
+ * ARCv2 IDU HW does not support inverse polarity, so these are the
+ * only interrupt types supported.
+ */
+ if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&mcip_lock, flags);
+
+ idu_set_mode(data->hwirq, true,
+ type & IRQ_TYPE_EDGE_RISING ? IDU_M_TRIG_EDGE :
+ IDU_M_TRIG_LEVEL,
+ false, 0);
+
+ raw_spin_unlock_irqrestore(&mcip_lock, flags);
+
+ return 0;
+}
+
+static void idu_irq_enable(struct irq_data *data)
+{
+ /*
+ * By default send all common interrupts to all available online CPUs.
+ * The affinity of common interrupts in IDU must be set manually since
+ * in some cases the kernel will not call irq_set_affinity() by itself:
+ * 1. When the kernel is not configured with support of SMP.
+ * 2. When the kernel is configured with support of SMP but upper
+ * interrupt controllers does not support setting of the affinity
+ * and cannot propagate it to IDU.
+ */
+ idu_irq_set_affinity(data, cpu_online_mask, false);
+ idu_irq_unmask(data);
+}
+
+static struct irq_chip idu_irq_chip = {
+ .name = "MCIP IDU Intc",
+ .irq_mask = idu_irq_mask,
+ .irq_unmask = idu_irq_unmask,
+ .irq_ack = idu_irq_ack,
+ .irq_mask_ack = idu_irq_mask_ack,
+ .irq_enable = idu_irq_enable,
+ .irq_set_type = idu_irq_set_type,
+#ifdef CONFIG_SMP
+ .irq_set_affinity = idu_irq_set_affinity,
+#endif
+
+};
+
+static void idu_cascade_isr(struct irq_desc *desc)
+{
+ struct irq_domain *idu_domain = irq_desc_get_handler_data(desc);
+ struct irq_chip *core_chip = irq_desc_get_chip(desc);
+ irq_hw_number_t core_hwirq = irqd_to_hwirq(irq_desc_get_irq_data(desc));
+ irq_hw_number_t idu_hwirq = core_hwirq - FIRST_EXT_IRQ;
+
+ chained_irq_enter(core_chip, desc);
+ generic_handle_domain_irq(idu_domain, idu_hwirq);
+ chained_irq_exit(core_chip, desc);
+}
+
+static int idu_irq_map(struct irq_domain *d, unsigned int virq, irq_hw_number_t hwirq)
+{
+ irq_set_chip_and_handler(virq, &idu_irq_chip, handle_level_irq);
+ irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
+
+ return 0;
+}
+
+static const struct irq_domain_ops idu_irq_ops = {
+ .xlate = irq_domain_xlate_onetwocell,
+ .map = idu_irq_map,
+};
+
+/*
+ * [16, 23]: Statically assigned always private-per-core (Timers, WDT, IPI)
+ * [24, 23+C]: If C > 0 then "C" common IRQs
+ * [24+C, N]: Not statically assigned, private-per-core
+ */
+
+
+static int __init
+idu_of_init(struct device_node *intc, struct device_node *parent)
+{
+ struct irq_domain *domain;
+ int nr_irqs;
+ int i, virq;
+ struct mcip_bcr mp;
+ struct mcip_idu_bcr idu_bcr;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+
+ if (!mp.idu)
+ panic("IDU not detected, but DeviceTree using it");
+
+ READ_BCR(ARC_REG_MCIP_IDU_BCR, idu_bcr);
+ nr_irqs = mcip_idu_bcr_to_nr_irqs(idu_bcr);
+
+ pr_info("MCIP: IDU supports %u common irqs\n", nr_irqs);
+
+ domain = irq_domain_add_linear(intc, nr_irqs, &idu_irq_ops, NULL);
+
+ /* Parent interrupts (core-intc) are already mapped */
+
+ for (i = 0; i < nr_irqs; i++) {
+ /* Mask all common interrupts by default */
+ idu_irq_mask_raw(i);
+
+ /*
+ * Return parent uplink IRQs (towards core intc) 24,25,.....
+ * this step has been done before already
+ * however we need it to get the parent virq and set IDU handler
+ * as first level isr
+ */
+ virq = irq_create_mapping(NULL, i + FIRST_EXT_IRQ);
+ BUG_ON(!virq);
+ irq_set_chained_handler_and_data(virq, idu_cascade_isr, domain);
+ }
+
+ __mcip_cmd(CMD_IDU_ENABLE, 0);
+
+ return 0;
+}
+IRQCHIP_DECLARE(arcv2_idu_intc, "snps,archs-idu-intc", idu_of_init);
diff --git a/arch/arc/kernel/module.c b/arch/arc/kernel/module.c
new file mode 100644
index 0000000000..c90c279047
--- /dev/null
+++ b/arch/arc/kernel/module.c
@@ -0,0 +1,146 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/module.h>
+#include <linux/moduleloader.h>
+#include <linux/kernel.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <asm/unwind.h>
+
+static inline void arc_write_me(unsigned short *addr, unsigned long value)
+{
+ *addr = (value & 0xffff0000) >> 16;
+ *(addr + 1) = (value & 0xffff);
+}
+
+/*
+ * This gets called before relocation loop in generic loader
+ * Make a note of the section index of unwinding section
+ */
+int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+ char *secstr, struct module *mod)
+{
+#ifdef CONFIG_ARC_DW2_UNWIND
+ mod->arch.unw_sec_idx = 0;
+ mod->arch.unw_info = NULL;
+#endif
+ mod->arch.secstr = secstr;
+ return 0;
+}
+
+void module_arch_cleanup(struct module *mod)
+{
+#ifdef CONFIG_ARC_DW2_UNWIND
+ if (mod->arch.unw_info)
+ unwind_remove_table(mod->arch.unw_info, 0);
+#endif
+}
+
+int apply_relocate_add(Elf32_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex, /* sec index for sym tbl */
+ unsigned int relsec, /* sec index for relo sec */
+ struct module *module)
+{
+ int i, n, relo_type;
+ Elf32_Rela *rel_entry = (void *)sechdrs[relsec].sh_addr;
+ Elf32_Sym *sym_entry, *sym_sec;
+ Elf32_Addr relocation, location, tgt_addr;
+ unsigned int tgtsec;
+
+ /*
+ * @relsec has relocations e.g. .rela.init.text
+ * @tgtsec is section to patch e.g. .init.text
+ */
+ tgtsec = sechdrs[relsec].sh_info;
+ tgt_addr = sechdrs[tgtsec].sh_addr;
+ sym_sec = (Elf32_Sym *) sechdrs[symindex].sh_addr;
+ n = sechdrs[relsec].sh_size / sizeof(*rel_entry);
+
+ pr_debug("\nSection to fixup %s @%x\n",
+ module->arch.secstr + sechdrs[tgtsec].sh_name, tgt_addr);
+ pr_debug("=========================================================\n");
+ pr_debug("r_off\tr_add\tst_value ADDRESS VALUE\n");
+ pr_debug("=========================================================\n");
+
+ /* Loop thru entries in relocation section */
+ for (i = 0; i < n; i++) {
+ const char *s;
+
+ /* This is where to make the change */
+ location = tgt_addr + rel_entry[i].r_offset;
+
+ /* This is the symbol it is referring to. Note that all
+ undefined symbols have been resolved. */
+ sym_entry = sym_sec + ELF32_R_SYM(rel_entry[i].r_info);
+
+ relocation = sym_entry->st_value + rel_entry[i].r_addend;
+
+ if (sym_entry->st_name == 0 && ELF_ST_TYPE (sym_entry->st_info) == STT_SECTION) {
+ s = module->arch.secstr + sechdrs[sym_entry->st_shndx].sh_name;
+ } else {
+ s = strtab + sym_entry->st_name;
+ }
+
+ pr_debug(" %x\t%x\t%x %x %x [%s]\n",
+ rel_entry[i].r_offset, rel_entry[i].r_addend,
+ sym_entry->st_value, location, relocation, s);
+
+ /* This assumes modules are built with -mlong-calls
+ * so any branches/jumps are absolute 32 bit jmps
+ * global data access again is abs 32 bit.
+ * Both of these are handled by same relocation type
+ */
+ relo_type = ELF32_R_TYPE(rel_entry[i].r_info);
+
+ if (likely(R_ARC_32_ME == relo_type)) /* ME ( S + A ) */
+ arc_write_me((unsigned short *)location, relocation);
+ else if (R_ARC_32 == relo_type) /* ( S + A ) */
+ *((Elf32_Addr *) location) = relocation;
+ else if (R_ARC_32_PCREL == relo_type) /* ( S + A ) - PDATA ) */
+ *((Elf32_Addr *) location) = relocation - location;
+ else
+ goto relo_err;
+
+ }
+
+#ifdef CONFIG_ARC_DW2_UNWIND
+ if (strcmp(module->arch.secstr+sechdrs[tgtsec].sh_name, ".eh_frame") == 0)
+ module->arch.unw_sec_idx = tgtsec;
+#endif
+
+ return 0;
+
+relo_err:
+ pr_err("%s: unknown relocation: %u\n",
+ module->name, ELF32_R_TYPE(rel_entry[i].r_info));
+ return -ENOEXEC;
+
+}
+
+/* Just before lift off: After sections have been relocated, we add the
+ * dwarf section to unwinder table pool
+ * This couldn't be done in module_frob_arch_sections() because
+ * relocations had not been applied by then
+ */
+int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
+ struct module *mod)
+{
+#ifdef CONFIG_ARC_DW2_UNWIND
+ void *unw;
+ int unwsec = mod->arch.unw_sec_idx;
+
+ if (unwsec) {
+ unw = unwind_add_table(mod, (void *)sechdrs[unwsec].sh_addr,
+ sechdrs[unwsec].sh_size);
+ mod->arch.unw_info = unw;
+ }
+#endif
+ return 0;
+}
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
new file mode 100644
index 0000000000..adff957962
--- /dev/null
+++ b/arch/arc/kernel/perf_event.c
@@ -0,0 +1,850 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Linux performance counter support for ARC CPUs.
+// This code is inspired by the perf support of various other architectures.
+//
+// Copyright (C) 2013-2018 Synopsys, Inc. (www.synopsys.com)
+
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <asm/arcregs.h>
+#include <asm/stacktrace.h>
+
+/* HW holds 8 symbols + one for null terminator */
+#define ARCPMU_EVENT_NAME_LEN 9
+
+/*
+ * Some ARC pct quirks:
+ *
+ * PERF_COUNT_HW_STALLED_CYCLES_BACKEND
+ * PERF_COUNT_HW_STALLED_CYCLES_FRONTEND
+ * The ARC 700 can either measure stalls per pipeline stage, or all stalls
+ * combined; for now we assign all stalls to STALLED_CYCLES_BACKEND
+ * and all pipeline flushes (e.g. caused by mispredicts, etc.) to
+ * STALLED_CYCLES_FRONTEND.
+ *
+ * We could start multiple performance counters and combine everything
+ * afterwards, but that makes it complicated.
+ *
+ * Note that I$ cache misses aren't counted by either of the two!
+ */
+
+/*
+ * ARC PCT has hardware conditions with fixed "names" but variable "indexes"
+ * (based on a specific RTL build)
+ * Below is the static map between perf generic/arc specific event_id and
+ * h/w condition names.
+ * At the time of probe, we loop thru each index and find it's name to
+ * complete the mapping of perf event_id to h/w index as latter is needed
+ * to program the counter really
+ */
+static const char * const arc_pmu_ev_hw_map[] = {
+ /* count cycles */
+ [PERF_COUNT_HW_CPU_CYCLES] = "crun",
+ [PERF_COUNT_HW_REF_CPU_CYCLES] = "crun",
+ [PERF_COUNT_HW_BUS_CYCLES] = "crun",
+
+ [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = "bflush",
+ [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = "bstall",
+
+ /* counts condition */
+ [PERF_COUNT_HW_INSTRUCTIONS] = "iall",
+ /* All jump instructions that are taken */
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = "ijmptak",
+#ifdef CONFIG_ISA_ARCV2
+ [PERF_COUNT_HW_BRANCH_MISSES] = "bpmp",
+#else
+ [PERF_COUNT_ARC_BPOK] = "bpok", /* NP-NT, PT-T, PNT-NT */
+ [PERF_COUNT_HW_BRANCH_MISSES] = "bpfail", /* NP-T, PT-NT, PNT-T */
+#endif
+ [PERF_COUNT_ARC_LDC] = "imemrdc", /* Instr: mem read cached */
+ [PERF_COUNT_ARC_STC] = "imemwrc", /* Instr: mem write cached */
+
+ [PERF_COUNT_ARC_DCLM] = "dclm", /* D-cache Load Miss */
+ [PERF_COUNT_ARC_DCSM] = "dcsm", /* D-cache Store Miss */
+ [PERF_COUNT_ARC_ICM] = "icm", /* I-cache Miss */
+ [PERF_COUNT_ARC_EDTLB] = "edtlb", /* D-TLB Miss */
+ [PERF_COUNT_ARC_EITLB] = "eitlb", /* I-TLB Miss */
+
+ [PERF_COUNT_HW_CACHE_REFERENCES] = "imemrdc", /* Instr: mem read cached */
+ [PERF_COUNT_HW_CACHE_MISSES] = "dclm", /* D-cache Load Miss */
+};
+
+#define C(_x) PERF_COUNT_HW_CACHE_##_x
+#define CACHE_OP_UNSUPPORTED 0xffff
+
+static const unsigned int arc_pmu_cache_map[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
+ [C(L1D)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = PERF_COUNT_ARC_LDC,
+ [C(RESULT_MISS)] = PERF_COUNT_ARC_DCLM,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = PERF_COUNT_ARC_STC,
+ [C(RESULT_MISS)] = PERF_COUNT_ARC_DCSM,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(L1I)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = PERF_COUNT_HW_INSTRUCTIONS,
+ [C(RESULT_MISS)] = PERF_COUNT_ARC_ICM,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(LL)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(DTLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = PERF_COUNT_ARC_LDC,
+ [C(RESULT_MISS)] = PERF_COUNT_ARC_EDTLB,
+ },
+ /* DTLB LD/ST Miss not segregated by h/w*/
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(ITLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = PERF_COUNT_ARC_EITLB,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(BPU)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = PERF_COUNT_HW_BRANCH_INSTRUCTIONS,
+ [C(RESULT_MISS)] = PERF_COUNT_HW_BRANCH_MISSES,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(NODE)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+};
+
+enum arc_pmu_attr_groups {
+ ARCPMU_ATTR_GR_EVENTS,
+ ARCPMU_ATTR_GR_FORMATS,
+ ARCPMU_NR_ATTR_GR
+};
+
+struct arc_pmu_raw_event_entry {
+ char name[ARCPMU_EVENT_NAME_LEN];
+};
+
+struct arc_pmu {
+ struct pmu pmu;
+ unsigned int irq;
+ int n_counters;
+ int n_events;
+ u64 max_period;
+ int ev_hw_idx[PERF_COUNT_ARC_HW_MAX];
+
+ struct arc_pmu_raw_event_entry *raw_entry;
+ struct attribute **attrs;
+ struct perf_pmu_events_attr *attr;
+ const struct attribute_group *attr_groups[ARCPMU_NR_ATTR_GR + 1];
+};
+
+struct arc_pmu_cpu {
+ /*
+ * A 1 bit for an index indicates that the counter is being used for
+ * an event. A 0 means that the counter can be used.
+ */
+ unsigned long used_mask[BITS_TO_LONGS(ARC_PERF_MAX_COUNTERS)];
+
+ /*
+ * The events that are active on the PMU for the given index.
+ */
+ struct perf_event *act_counter[ARC_PERF_MAX_COUNTERS];
+};
+
+struct arc_callchain_trace {
+ int depth;
+ void *perf_stuff;
+};
+
+static int callchain_trace(unsigned int addr, void *data)
+{
+ struct arc_callchain_trace *ctrl = data;
+ struct perf_callchain_entry_ctx *entry = ctrl->perf_stuff;
+
+ perf_callchain_store(entry, addr);
+
+ if (ctrl->depth++ < 3)
+ return 0;
+
+ return -1;
+}
+
+void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs)
+{
+ struct arc_callchain_trace ctrl = {
+ .depth = 0,
+ .perf_stuff = entry,
+ };
+
+ arc_unwind_core(NULL, regs, callchain_trace, &ctrl);
+}
+
+void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs)
+{
+ /*
+ * User stack can't be unwound trivially with kernel dwarf unwinder
+ * So for now just record the user PC
+ */
+ perf_callchain_store(entry, instruction_pointer(regs));
+}
+
+static struct arc_pmu *arc_pmu;
+static DEFINE_PER_CPU(struct arc_pmu_cpu, arc_pmu_cpu);
+
+/* read counter #idx; note that counter# != event# on ARC! */
+static u64 arc_pmu_read_counter(int idx)
+{
+ u32 tmp;
+ u64 result;
+
+ /*
+ * ARC supports making 'snapshots' of the counters, so we don't
+ * need to care about counters wrapping to 0 underneath our feet
+ */
+ write_aux_reg(ARC_REG_PCT_INDEX, idx);
+ tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
+ write_aux_reg(ARC_REG_PCT_CONTROL, tmp | ARC_REG_PCT_CONTROL_SN);
+ result = (u64) (read_aux_reg(ARC_REG_PCT_SNAPH)) << 32;
+ result |= read_aux_reg(ARC_REG_PCT_SNAPL);
+
+ return result;
+}
+
+static void arc_perf_event_update(struct perf_event *event,
+ struct hw_perf_event *hwc, int idx)
+{
+ u64 prev_raw_count = local64_read(&hwc->prev_count);
+ u64 new_raw_count = arc_pmu_read_counter(idx);
+ s64 delta = new_raw_count - prev_raw_count;
+
+ /*
+ * We aren't afraid of hwc->prev_count changing beneath our feet
+ * because there's no way for us to re-enter this function anytime.
+ */
+ local64_set(&hwc->prev_count, new_raw_count);
+ local64_add(delta, &event->count);
+ local64_sub(delta, &hwc->period_left);
+}
+
+static void arc_pmu_read(struct perf_event *event)
+{
+ arc_perf_event_update(event, &event->hw, event->hw.idx);
+}
+
+static int arc_pmu_cache_event(u64 config)
+{
+ unsigned int cache_type, cache_op, cache_result;
+ int ret;
+
+ cache_type = (config >> 0) & 0xff;
+ cache_op = (config >> 8) & 0xff;
+ cache_result = (config >> 16) & 0xff;
+ if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
+ return -EINVAL;
+ if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
+ return -EINVAL;
+ if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+ return -EINVAL;
+
+ ret = arc_pmu_cache_map[cache_type][cache_op][cache_result];
+
+ if (ret == CACHE_OP_UNSUPPORTED)
+ return -ENOENT;
+
+ pr_debug("init cache event: type/op/result %d/%d/%d with h/w %d \'%s\'\n",
+ cache_type, cache_op, cache_result, ret,
+ arc_pmu_ev_hw_map[ret]);
+
+ return ret;
+}
+
+/* initializes hw_perf_event structure if event is supported */
+static int arc_pmu_event_init(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int ret;
+
+ if (!is_sampling_event(event)) {
+ hwc->sample_period = arc_pmu->max_period;
+ hwc->last_period = hwc->sample_period;
+ local64_set(&hwc->period_left, hwc->sample_period);
+ }
+
+ hwc->config = 0;
+
+ if (is_isa_arcv2()) {
+ /* "exclude user" means "count only kernel" */
+ if (event->attr.exclude_user)
+ hwc->config |= ARC_REG_PCT_CONFIG_KERN;
+
+ /* "exclude kernel" means "count only user" */
+ if (event->attr.exclude_kernel)
+ hwc->config |= ARC_REG_PCT_CONFIG_USER;
+ }
+
+ switch (event->attr.type) {
+ case PERF_TYPE_HARDWARE:
+ if (event->attr.config >= PERF_COUNT_HW_MAX)
+ return -ENOENT;
+ if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
+ return -ENOENT;
+ hwc->config |= arc_pmu->ev_hw_idx[event->attr.config];
+ pr_debug("init event %d with h/w %08x \'%s\'\n",
+ (int)event->attr.config, (int)hwc->config,
+ arc_pmu_ev_hw_map[event->attr.config]);
+ return 0;
+
+ case PERF_TYPE_HW_CACHE:
+ ret = arc_pmu_cache_event(event->attr.config);
+ if (ret < 0)
+ return ret;
+ hwc->config |= arc_pmu->ev_hw_idx[ret];
+ pr_debug("init cache event with h/w %08x \'%s\'\n",
+ (int)hwc->config, arc_pmu_ev_hw_map[ret]);
+ return 0;
+
+ case PERF_TYPE_RAW:
+ if (event->attr.config >= arc_pmu->n_events)
+ return -ENOENT;
+
+ hwc->config |= event->attr.config;
+ pr_debug("init raw event with idx %lld \'%s\'\n",
+ event->attr.config,
+ arc_pmu->raw_entry[event->attr.config].name);
+
+ return 0;
+
+ default:
+ return -ENOENT;
+ }
+}
+
+/* starts all counters */
+static void arc_pmu_enable(struct pmu *pmu)
+{
+ u32 tmp;
+ tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
+ write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x1);
+}
+
+/* stops all counters */
+static void arc_pmu_disable(struct pmu *pmu)
+{
+ u32 tmp;
+ tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
+ write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x0);
+}
+
+static int arc_pmu_event_set_period(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ s64 left = local64_read(&hwc->period_left);
+ s64 period = hwc->sample_period;
+ int idx = hwc->idx;
+ int overflow = 0;
+ u64 value;
+
+ if (unlikely(left <= -period)) {
+ /* left underflowed by more than period. */
+ left = period;
+ local64_set(&hwc->period_left, left);
+ hwc->last_period = period;
+ overflow = 1;
+ } else if (unlikely(left <= 0)) {
+ /* left underflowed by less than period. */
+ left += period;
+ local64_set(&hwc->period_left, left);
+ hwc->last_period = period;
+ overflow = 1;
+ }
+
+ if (left > arc_pmu->max_period)
+ left = arc_pmu->max_period;
+
+ value = arc_pmu->max_period - left;
+ local64_set(&hwc->prev_count, value);
+
+ /* Select counter */
+ write_aux_reg(ARC_REG_PCT_INDEX, idx);
+
+ /* Write value */
+ write_aux_reg(ARC_REG_PCT_COUNTL, lower_32_bits(value));
+ write_aux_reg(ARC_REG_PCT_COUNTH, upper_32_bits(value));
+
+ perf_event_update_userpage(event);
+
+ return overflow;
+}
+
+/*
+ * Assigns hardware counter to hardware condition.
+ * Note that there is no separate start/stop mechanism;
+ * stopping is achieved by assigning the 'never' condition
+ */
+static void arc_pmu_start(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ if (WARN_ON_ONCE(idx == -1))
+ return;
+
+ if (flags & PERF_EF_RELOAD)
+ WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
+
+ hwc->state = 0;
+
+ arc_pmu_event_set_period(event);
+
+ /* Enable interrupt for this counter */
+ if (is_sampling_event(event))
+ write_aux_reg(ARC_REG_PCT_INT_CTRL,
+ read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx));
+
+ /* enable ARC pmu here */
+ write_aux_reg(ARC_REG_PCT_INDEX, idx); /* counter # */
+ write_aux_reg(ARC_REG_PCT_CONFIG, hwc->config); /* condition */
+}
+
+static void arc_pmu_stop(struct perf_event *event, int flags)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ /* Disable interrupt for this counter */
+ if (is_sampling_event(event)) {
+ /*
+ * Reset interrupt flag by writing of 1. This is required
+ * to make sure pending interrupt was not left.
+ */
+ write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx));
+ write_aux_reg(ARC_REG_PCT_INT_CTRL,
+ read_aux_reg(ARC_REG_PCT_INT_CTRL) & ~BIT(idx));
+ }
+
+ if (!(event->hw.state & PERF_HES_STOPPED)) {
+ /* stop hw counter here */
+ write_aux_reg(ARC_REG_PCT_INDEX, idx);
+
+ /* condition code #0 is always "never" */
+ write_aux_reg(ARC_REG_PCT_CONFIG, 0);
+
+ event->hw.state |= PERF_HES_STOPPED;
+ }
+
+ if ((flags & PERF_EF_UPDATE) &&
+ !(event->hw.state & PERF_HES_UPTODATE)) {
+ arc_perf_event_update(event, &event->hw, idx);
+ event->hw.state |= PERF_HES_UPTODATE;
+ }
+}
+
+static void arc_pmu_del(struct perf_event *event, int flags)
+{
+ struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
+
+ arc_pmu_stop(event, PERF_EF_UPDATE);
+ __clear_bit(event->hw.idx, pmu_cpu->used_mask);
+
+ pmu_cpu->act_counter[event->hw.idx] = 0;
+
+ perf_event_update_userpage(event);
+}
+
+/* allocate hardware counter and optionally start counting */
+static int arc_pmu_add(struct perf_event *event, int flags)
+{
+ struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
+ struct hw_perf_event *hwc = &event->hw;
+ int idx;
+
+ idx = ffz(pmu_cpu->used_mask[0]);
+ if (idx == arc_pmu->n_counters)
+ return -EAGAIN;
+
+ __set_bit(idx, pmu_cpu->used_mask);
+ hwc->idx = idx;
+
+ write_aux_reg(ARC_REG_PCT_INDEX, idx);
+
+ pmu_cpu->act_counter[idx] = event;
+
+ if (is_sampling_event(event)) {
+ /* Mimic full counter overflow as other arches do */
+ write_aux_reg(ARC_REG_PCT_INT_CNTL,
+ lower_32_bits(arc_pmu->max_period));
+ write_aux_reg(ARC_REG_PCT_INT_CNTH,
+ upper_32_bits(arc_pmu->max_period));
+ }
+
+ write_aux_reg(ARC_REG_PCT_CONFIG, 0);
+ write_aux_reg(ARC_REG_PCT_COUNTL, 0);
+ write_aux_reg(ARC_REG_PCT_COUNTH, 0);
+ local64_set(&hwc->prev_count, 0);
+
+ hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+ if (flags & PERF_EF_START)
+ arc_pmu_start(event, PERF_EF_RELOAD);
+
+ perf_event_update_userpage(event);
+
+ return 0;
+}
+
+#ifdef CONFIG_ISA_ARCV2
+static irqreturn_t arc_pmu_intr(int irq, void *dev)
+{
+ struct perf_sample_data data;
+ struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
+ struct pt_regs *regs;
+ unsigned int active_ints;
+ int idx;
+
+ arc_pmu_disable(&arc_pmu->pmu);
+
+ active_ints = read_aux_reg(ARC_REG_PCT_INT_ACT);
+ if (!active_ints)
+ goto done;
+
+ regs = get_irq_regs();
+
+ do {
+ struct perf_event *event;
+ struct hw_perf_event *hwc;
+
+ idx = __ffs(active_ints);
+
+ /* Reset interrupt flag by writing of 1 */
+ write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx));
+
+ /*
+ * On reset of "interrupt active" bit corresponding
+ * "interrupt enable" bit gets automatically reset as well.
+ * Now we need to re-enable interrupt for the counter.
+ */
+ write_aux_reg(ARC_REG_PCT_INT_CTRL,
+ read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx));
+
+ event = pmu_cpu->act_counter[idx];
+ hwc = &event->hw;
+
+ WARN_ON_ONCE(hwc->idx != idx);
+
+ arc_perf_event_update(event, &event->hw, event->hw.idx);
+ perf_sample_data_init(&data, 0, hwc->last_period);
+ if (arc_pmu_event_set_period(event)) {
+ if (perf_event_overflow(event, &data, regs))
+ arc_pmu_stop(event, 0);
+ }
+
+ active_ints &= ~BIT(idx);
+ } while (active_ints);
+
+done:
+ arc_pmu_enable(&arc_pmu->pmu);
+
+ return IRQ_HANDLED;
+}
+#else
+
+static irqreturn_t arc_pmu_intr(int irq, void *dev)
+{
+ return IRQ_NONE;
+}
+
+#endif /* CONFIG_ISA_ARCV2 */
+
+static void arc_cpu_pmu_irq_init(void *data)
+{
+ int irq = *(int *)data;
+
+ enable_percpu_irq(irq, IRQ_TYPE_NONE);
+
+ /* Clear all pending interrupt flags */
+ write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff);
+}
+
+/* Event field occupies the bottom 15 bits of our config field */
+PMU_FORMAT_ATTR(event, "config:0-14");
+static struct attribute *arc_pmu_format_attrs[] = {
+ &format_attr_event.attr,
+ NULL,
+};
+
+static struct attribute_group arc_pmu_format_attr_gr = {
+ .name = "format",
+ .attrs = arc_pmu_format_attrs,
+};
+
+static ssize_t arc_pmu_events_sysfs_show(struct device *dev,
+ struct device_attribute *attr,
+ char *page)
+{
+ struct perf_pmu_events_attr *pmu_attr;
+
+ pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
+ return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
+}
+
+/*
+ * We don't add attrs here as we don't have pre-defined list of perf events.
+ * We will generate and add attrs dynamically in probe() after we read HW
+ * configuration.
+ */
+static struct attribute_group arc_pmu_events_attr_gr = {
+ .name = "events",
+};
+
+static void arc_pmu_add_raw_event_attr(int j, char *str)
+{
+ memmove(arc_pmu->raw_entry[j].name, str, ARCPMU_EVENT_NAME_LEN - 1);
+ arc_pmu->attr[j].attr.attr.name = arc_pmu->raw_entry[j].name;
+ arc_pmu->attr[j].attr.attr.mode = VERIFY_OCTAL_PERMISSIONS(0444);
+ arc_pmu->attr[j].attr.show = arc_pmu_events_sysfs_show;
+ arc_pmu->attr[j].id = j;
+ arc_pmu->attrs[j] = &(arc_pmu->attr[j].attr.attr);
+}
+
+static int arc_pmu_raw_alloc(struct device *dev)
+{
+ arc_pmu->attr = devm_kmalloc_array(dev, arc_pmu->n_events + 1,
+ sizeof(*arc_pmu->attr), GFP_KERNEL | __GFP_ZERO);
+ if (!arc_pmu->attr)
+ return -ENOMEM;
+
+ arc_pmu->attrs = devm_kmalloc_array(dev, arc_pmu->n_events + 1,
+ sizeof(*arc_pmu->attrs), GFP_KERNEL | __GFP_ZERO);
+ if (!arc_pmu->attrs)
+ return -ENOMEM;
+
+ arc_pmu->raw_entry = devm_kmalloc_array(dev, arc_pmu->n_events,
+ sizeof(*arc_pmu->raw_entry), GFP_KERNEL | __GFP_ZERO);
+ if (!arc_pmu->raw_entry)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static inline bool event_in_hw_event_map(int i, char *name)
+{
+ if (!arc_pmu_ev_hw_map[i])
+ return false;
+
+ if (!strlen(arc_pmu_ev_hw_map[i]))
+ return false;
+
+ if (strcmp(arc_pmu_ev_hw_map[i], name))
+ return false;
+
+ return true;
+}
+
+static void arc_pmu_map_hw_event(int j, char *str)
+{
+ int i;
+
+ /* See if HW condition has been mapped to a perf event_id */
+ for (i = 0; i < ARRAY_SIZE(arc_pmu_ev_hw_map); i++) {
+ if (event_in_hw_event_map(i, str)) {
+ pr_debug("mapping perf event %2d to h/w event \'%8s\' (idx %d)\n",
+ i, str, j);
+ arc_pmu->ev_hw_idx[i] = j;
+ }
+ }
+}
+
+static int arc_pmu_device_probe(struct platform_device *pdev)
+{
+ struct arc_reg_pct_build pct_bcr;
+ struct arc_reg_cc_build cc_bcr;
+ int i, has_interrupts, irq = -1;
+ int counter_size; /* in bits */
+
+ union cc_name {
+ struct {
+ u32 word0, word1;
+ char sentinel;
+ } indiv;
+ char str[ARCPMU_EVENT_NAME_LEN];
+ } cc_name;
+
+
+ READ_BCR(ARC_REG_PCT_BUILD, pct_bcr);
+ if (!pct_bcr.v) {
+ pr_err("This core does not have performance counters!\n");
+ return -ENODEV;
+ }
+ BUILD_BUG_ON(ARC_PERF_MAX_COUNTERS > 32);
+ if (WARN_ON(pct_bcr.c > ARC_PERF_MAX_COUNTERS))
+ return -EINVAL;
+
+ READ_BCR(ARC_REG_CC_BUILD, cc_bcr);
+ if (WARN(!cc_bcr.v, "Counters exist but No countable conditions?"))
+ return -EINVAL;
+
+ arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu), GFP_KERNEL);
+ if (!arc_pmu)
+ return -ENOMEM;
+
+ arc_pmu->n_events = cc_bcr.c;
+
+ if (arc_pmu_raw_alloc(&pdev->dev))
+ return -ENOMEM;
+
+ has_interrupts = is_isa_arcv2() ? pct_bcr.i : 0;
+
+ arc_pmu->n_counters = pct_bcr.c;
+ counter_size = 32 + (pct_bcr.s << 4);
+
+ arc_pmu->max_period = (1ULL << counter_size) / 2 - 1ULL;
+
+ pr_info("ARC perf\t: %d counters (%d bits), %d conditions%s\n",
+ arc_pmu->n_counters, counter_size, cc_bcr.c,
+ has_interrupts ? ", [overflow IRQ support]" : "");
+
+ cc_name.str[ARCPMU_EVENT_NAME_LEN - 1] = 0;
+ for (i = 0; i < PERF_COUNT_ARC_HW_MAX; i++)
+ arc_pmu->ev_hw_idx[i] = -1;
+
+ /* loop thru all available h/w condition indexes */
+ for (i = 0; i < cc_bcr.c; i++) {
+ write_aux_reg(ARC_REG_CC_INDEX, i);
+ cc_name.indiv.word0 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME0));
+ cc_name.indiv.word1 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME1));
+
+ arc_pmu_map_hw_event(i, cc_name.str);
+ arc_pmu_add_raw_event_attr(i, cc_name.str);
+ }
+
+ arc_pmu_events_attr_gr.attrs = arc_pmu->attrs;
+ arc_pmu->attr_groups[ARCPMU_ATTR_GR_EVENTS] = &arc_pmu_events_attr_gr;
+ arc_pmu->attr_groups[ARCPMU_ATTR_GR_FORMATS] = &arc_pmu_format_attr_gr;
+
+ arc_pmu->pmu = (struct pmu) {
+ .pmu_enable = arc_pmu_enable,
+ .pmu_disable = arc_pmu_disable,
+ .event_init = arc_pmu_event_init,
+ .add = arc_pmu_add,
+ .del = arc_pmu_del,
+ .start = arc_pmu_start,
+ .stop = arc_pmu_stop,
+ .read = arc_pmu_read,
+ .attr_groups = arc_pmu->attr_groups,
+ };
+
+ if (has_interrupts) {
+ irq = platform_get_irq(pdev, 0);
+ if (irq >= 0) {
+ int ret;
+
+ arc_pmu->irq = irq;
+
+ /* intc map function ensures irq_set_percpu_devid() called */
+ ret = request_percpu_irq(irq, arc_pmu_intr, "ARC perf counters",
+ this_cpu_ptr(&arc_pmu_cpu));
+
+ if (!ret)
+ on_each_cpu(arc_cpu_pmu_irq_init, &irq, 1);
+ else
+ irq = -1;
+ }
+
+ }
+
+ if (irq == -1)
+ arc_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
+
+ /*
+ * perf parser doesn't really like '-' symbol in events name, so let's
+ * use '_' in arc pct name as it goes to kernel PMU event prefix.
+ */
+ return perf_pmu_register(&arc_pmu->pmu, "arc_pct", PERF_TYPE_RAW);
+}
+
+static const struct of_device_id arc_pmu_match[] = {
+ { .compatible = "snps,arc700-pct" },
+ { .compatible = "snps,archs-pct" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, arc_pmu_match);
+
+static struct platform_driver arc_pmu_driver = {
+ .driver = {
+ .name = "arc-pct",
+ .of_match_table = of_match_ptr(arc_pmu_match),
+ },
+ .probe = arc_pmu_device_probe,
+};
+
+module_platform_driver(arc_pmu_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mischa Jonker <mjonker@synopsys.com>");
+MODULE_DESCRIPTION("ARC PMU driver");
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
new file mode 100644
index 0000000000..186ceab661
--- /dev/null
+++ b/arch/arc/kernel/process.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * Amit Bhor, Kanika Nema: Codito Technologies 2004
+ */
+
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/elf.h>
+#include <linux/tick.h>
+
+#include <asm/fpu.h>
+
+SYSCALL_DEFINE1(arc_settls, void *, user_tls_data_ptr)
+{
+ task_thread_info(current)->thr_ptr = (unsigned int)user_tls_data_ptr;
+ return 0;
+}
+
+/*
+ * We return the user space TLS data ptr as sys-call return code
+ * Ideally it should be copy to user.
+ * However we can cheat by the fact that some sys-calls do return
+ * absurdly high values
+ * Since the tls dat aptr is not going to be in range of 0xFFFF_xxxx
+ * it won't be considered a sys-call error
+ * and it will be loads better than copy-to-user, which is a definite
+ * D-TLB Miss
+ */
+SYSCALL_DEFINE0(arc_gettls)
+{
+ return task_thread_info(current)->thr_ptr;
+}
+
+SYSCALL_DEFINE3(arc_usr_cmpxchg, int __user *, uaddr, int, expected, int, new)
+{
+ struct pt_regs *regs = current_pt_regs();
+ u32 uval;
+ int ret;
+
+ /*
+ * This is only for old cores lacking LLOCK/SCOND, which by definition
+ * can't possibly be SMP. Thus doesn't need to be SMP safe.
+ * And this also helps reduce the overhead for serializing in
+ * the UP case
+ */
+ WARN_ON_ONCE(IS_ENABLED(CONFIG_SMP));
+
+ /* Z indicates to userspace if operation succeeded */
+ regs->status32 &= ~STATUS_Z_MASK;
+
+ ret = access_ok(uaddr, sizeof(*uaddr));
+ if (!ret)
+ goto fail;
+
+again:
+ preempt_disable();
+
+ ret = __get_user(uval, uaddr);
+ if (ret)
+ goto fault;
+
+ if (uval != expected)
+ goto out;
+
+ ret = __put_user(new, uaddr);
+ if (ret)
+ goto fault;
+
+ regs->status32 |= STATUS_Z_MASK;
+
+out:
+ preempt_enable();
+ return uval;
+
+fault:
+ preempt_enable();
+
+ if (unlikely(ret != -EFAULT))
+ goto fail;
+
+ mmap_read_lock(current->mm);
+ ret = fixup_user_fault(current->mm, (unsigned long) uaddr,
+ FAULT_FLAG_WRITE, NULL);
+ mmap_read_unlock(current->mm);
+
+ if (likely(!ret))
+ goto again;
+
+fail:
+ force_sig(SIGSEGV);
+ return ret;
+}
+
+#ifdef CONFIG_ISA_ARCV2
+
+void arch_cpu_idle(void)
+{
+ /* Re-enable interrupts <= default irq priority before committing SLEEP */
+ const unsigned int arg = 0x10 | ARCV2_IRQ_DEF_PRIO;
+
+ __asm__ __volatile__(
+ "sleep %0 \n"
+ :
+ :"I"(arg)); /* can't be "r" has to be embedded const */
+
+ raw_local_irq_disable();
+}
+
+#else /* ARC700 */
+
+void arch_cpu_idle(void)
+{
+ /* sleep, but enable both set E1/E2 (levels of interrupts) before committing */
+ __asm__ __volatile__("sleep 0x3 \n");
+ raw_local_irq_disable();
+}
+
+#endif
+
+asmlinkage void ret_from_fork(void);
+
+/*
+ * Copy architecture-specific thread state
+ *
+ * Layout of Child kernel mode stack as setup at the end of this function is
+ *
+ * | ... |
+ * | ... |
+ * | unused |
+ * | |
+ * ------------------
+ * | r25 | <==== top of Stack (thread_info.ksp)
+ * ~ ~
+ * | --to-- | (CALLEE Regs of kernel mode)
+ * | r13 |
+ * ------------------
+ * | fp |
+ * | blink | @ret_from_fork
+ * ------------------
+ * | |
+ * ~ ~
+ * ~ ~
+ * | |
+ * ------------------
+ * | r12 |
+ * ~ ~
+ * | --to-- | (scratch Regs of user mode)
+ * | r0 |
+ * ------------------
+ * | SP |
+ * | orig_r0 |
+ * | event/ECR |
+ * ------------------ <===== END of PAGE
+ */
+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 *c_regs; /* child's pt_regs */
+ unsigned long *childksp; /* to unwind out of __switch_to() */
+ struct callee_regs *c_callee; /* child's callee regs */
+ struct callee_regs *parent_callee; /* paren't callee */
+ struct pt_regs *regs = current_pt_regs();
+
+ /* Mark the specific anchors to begin with (see pic above) */
+ c_regs = task_pt_regs(p);
+ childksp = (unsigned long *)c_regs - 2; /* 2 words for FP/BLINK */
+ c_callee = ((struct callee_regs *)childksp) - 1;
+
+ /*
+ * __switch_to() uses thread_info.ksp to start unwinding stack
+ * For kernel threads we don't need to create callee regs, the
+ * stack layout nevertheless needs to remain the same.
+ * Also, since __switch_to anyways unwinds callee regs, we use
+ * this to populate kernel thread entry-pt/args into callee regs,
+ * so that ret_from_kernel_thread() becomes simpler.
+ */
+ task_thread_info(p)->ksp = (unsigned long)c_callee; /* THREAD_INFO_KSP */
+
+ /* __switch_to expects FP(0), BLINK(return addr) at top */
+ childksp[0] = 0; /* fp */
+ childksp[1] = (unsigned long)ret_from_fork; /* blink */
+
+ if (unlikely(args->fn)) {
+ memset(c_regs, 0, sizeof(struct pt_regs));
+
+ c_callee->r13 = (unsigned long)args->fn_arg;
+ c_callee->r14 = (unsigned long)args->fn;
+
+ return 0;
+ }
+
+ /*--------- User Task Only --------------*/
+
+ /* __switch_to expects FP(0), BLINK(return addr) at top of stack */
+ childksp[0] = 0; /* for POP fp */
+ childksp[1] = (unsigned long)ret_from_fork; /* for POP blink */
+
+ /* Copy parents pt regs on child's kernel mode stack */
+ *c_regs = *regs;
+
+ if (usp)
+ c_regs->sp = usp;
+
+ c_regs->r0 = 0; /* fork returns 0 in child */
+
+ parent_callee = ((struct callee_regs *)regs) - 1;
+ *c_callee = *parent_callee;
+
+ if (unlikely(clone_flags & CLONE_SETTLS)) {
+ /*
+ * set task's userland tls data ptr from 4th arg
+ * clone C-lib call is difft from clone sys-call
+ */
+ task_thread_info(p)->thr_ptr = tls;
+ } else {
+ /* Normal fork case: set parent's TLS ptr in child */
+ task_thread_info(p)->thr_ptr =
+ task_thread_info(current)->thr_ptr;
+ }
+
+
+ /*
+ * setup usermode thread pointer #1:
+ * when child is picked by scheduler, __switch_to() uses @c_callee to
+ * populate usermode callee regs: this works (despite being in a kernel
+ * function) since special return path for child @ret_from_fork()
+ * ensures those regs are not clobbered all the way to RTIE to usermode
+ */
+ c_callee->r25 = task_thread_info(p)->thr_ptr;
+
+ return 0;
+}
+
+/*
+ * Do necessary setup to start up a new user task
+ */
+void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
+{
+ regs->sp = usp;
+ regs->ret = pc;
+
+ /*
+ * [U]ser Mode bit set
+ * [L] ZOL loop inhibited to begin with - cleared by a LP insn
+ * Interrupts enabled
+ */
+ regs->status32 = STATUS_U_MASK | STATUS_L_MASK | ISA_INIT_STATUS_BITS;
+
+ fpu_init_task(regs);
+
+ /* bogus seed values for debugging */
+ regs->lp_start = 0x10;
+ regs->lp_end = 0x80;
+}
+
+/*
+ * Some archs flush debug and FPU info here
+ */
+void flush_thread(void)
+{
+}
+
+int elf_check_arch(const struct elf32_hdr *x)
+{
+ unsigned int eflags;
+
+ if (x->e_machine != EM_ARC_INUSE) {
+ pr_err("ELF not built for %s ISA\n",
+ is_isa_arcompact() ? "ARCompact":"ARCv2");
+ return 0;
+ }
+
+ eflags = x->e_flags;
+ if ((eflags & EF_ARC_OSABI_MSK) != EF_ARC_OSABI_CURRENT) {
+ pr_err("ABI mismatch - you need newer toolchain\n");
+ force_fatal_sig(SIGSEGV);
+ return 0;
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL(elf_check_arch);
diff --git a/arch/arc/kernel/ptrace.c b/arch/arc/kernel/ptrace.c
new file mode 100644
index 0000000000..e0c233c178
--- /dev/null
+++ b/arch/arc/kernel/ptrace.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/ptrace.h>
+#include <linux/sched/task_stack.h>
+#include <linux/regset.h>
+#include <linux/unistd.h>
+#include <linux/elf.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/syscalls.h>
+
+struct pt_regs_offset {
+ const char *name;
+ int offset;
+};
+
+#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
+#define REG_OFFSET_END {.name = NULL, .offset = 0}
+
+#ifdef CONFIG_ISA_ARCOMPACT
+static const struct pt_regs_offset regoffset_table[] = {
+ REG_OFFSET_NAME(bta),
+ REG_OFFSET_NAME(lp_start),
+ REG_OFFSET_NAME(lp_end),
+ REG_OFFSET_NAME(lp_count),
+ REG_OFFSET_NAME(status32),
+ REG_OFFSET_NAME(ret),
+ REG_OFFSET_NAME(blink),
+ REG_OFFSET_NAME(fp),
+ REG_OFFSET_NAME(r26),
+ REG_OFFSET_NAME(r12),
+ REG_OFFSET_NAME(r11),
+ REG_OFFSET_NAME(r10),
+ REG_OFFSET_NAME(r9),
+ REG_OFFSET_NAME(r8),
+ REG_OFFSET_NAME(r7),
+ REG_OFFSET_NAME(r6),
+ REG_OFFSET_NAME(r5),
+ REG_OFFSET_NAME(r4),
+ REG_OFFSET_NAME(r3),
+ REG_OFFSET_NAME(r2),
+ REG_OFFSET_NAME(r1),
+ REG_OFFSET_NAME(r0),
+ REG_OFFSET_NAME(sp),
+ REG_OFFSET_NAME(orig_r0),
+ REG_OFFSET_NAME(ecr),
+ REG_OFFSET_END,
+};
+
+#else
+
+static const struct pt_regs_offset regoffset_table[] = {
+ REG_OFFSET_NAME(orig_r0),
+ REG_OFFSET_NAME(ecr),
+ REG_OFFSET_NAME(bta),
+ REG_OFFSET_NAME(r26),
+ REG_OFFSET_NAME(fp),
+ REG_OFFSET_NAME(sp),
+ REG_OFFSET_NAME(r12),
+ REG_OFFSET_NAME(r30),
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+ REG_OFFSET_NAME(r58),
+ REG_OFFSET_NAME(r59),
+#endif
+#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS
+ REG_OFFSET_NAME(DSP_CTRL),
+#endif
+ REG_OFFSET_NAME(r0),
+ REG_OFFSET_NAME(r1),
+ REG_OFFSET_NAME(r2),
+ REG_OFFSET_NAME(r3),
+ REG_OFFSET_NAME(r4),
+ REG_OFFSET_NAME(r5),
+ REG_OFFSET_NAME(r6),
+ REG_OFFSET_NAME(r7),
+ REG_OFFSET_NAME(r8),
+ REG_OFFSET_NAME(r9),
+ REG_OFFSET_NAME(r10),
+ REG_OFFSET_NAME(r11),
+ REG_OFFSET_NAME(blink),
+ REG_OFFSET_NAME(lp_end),
+ REG_OFFSET_NAME(lp_start),
+ REG_OFFSET_NAME(lp_count),
+ REG_OFFSET_NAME(ei),
+ REG_OFFSET_NAME(ldi),
+ REG_OFFSET_NAME(jli),
+ REG_OFFSET_NAME(ret),
+ REG_OFFSET_NAME(status32),
+ REG_OFFSET_END,
+};
+#endif
+
+static struct callee_regs *task_callee_regs(struct task_struct *tsk)
+{
+ struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg;
+ return tmp;
+}
+
+static int genregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ const struct pt_regs *ptregs = task_pt_regs(target);
+ const struct callee_regs *cregs = task_callee_regs(target);
+ unsigned int stop_pc_val;
+
+ membuf_zero(&to, 4); // pad
+ membuf_store(&to, ptregs->bta);
+ membuf_store(&to, ptregs->lp_start);
+ membuf_store(&to, ptregs->lp_end);
+ membuf_store(&to, ptregs->lp_count);
+ membuf_store(&to, ptregs->status32);
+ membuf_store(&to, ptregs->ret);
+ membuf_store(&to, ptregs->blink);
+ membuf_store(&to, ptregs->fp);
+ membuf_store(&to, ptregs->r26); // gp
+ membuf_store(&to, ptregs->r12);
+ membuf_store(&to, ptregs->r11);
+ membuf_store(&to, ptregs->r10);
+ membuf_store(&to, ptregs->r9);
+ membuf_store(&to, ptregs->r8);
+ membuf_store(&to, ptregs->r7);
+ membuf_store(&to, ptregs->r6);
+ membuf_store(&to, ptregs->r5);
+ membuf_store(&to, ptregs->r4);
+ membuf_store(&to, ptregs->r3);
+ membuf_store(&to, ptregs->r2);
+ membuf_store(&to, ptregs->r1);
+ membuf_store(&to, ptregs->r0);
+ membuf_store(&to, ptregs->sp);
+ membuf_zero(&to, 4); // pad2
+ membuf_store(&to, cregs->r25);
+ membuf_store(&to, cregs->r24);
+ membuf_store(&to, cregs->r23);
+ membuf_store(&to, cregs->r22);
+ membuf_store(&to, cregs->r21);
+ membuf_store(&to, cregs->r20);
+ membuf_store(&to, cregs->r19);
+ membuf_store(&to, cregs->r18);
+ membuf_store(&to, cregs->r17);
+ membuf_store(&to, cregs->r16);
+ membuf_store(&to, cregs->r15);
+ membuf_store(&to, cregs->r14);
+ membuf_store(&to, cregs->r13);
+ membuf_store(&to, target->thread.fault_address); // efa
+
+ if (in_brkpt_trap(ptregs)) {
+ stop_pc_val = target->thread.fault_address;
+ pr_debug("\t\tstop_pc (brk-pt)\n");
+ } else {
+ stop_pc_val = ptregs->ret;
+ pr_debug("\t\tstop_pc (others)\n");
+ }
+
+ return membuf_store(&to, stop_pc_val); // stop_pc
+}
+
+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)
+{
+ const struct pt_regs *ptregs = task_pt_regs(target);
+ const struct callee_regs *cregs = task_callee_regs(target);
+ int ret = 0;
+
+#define REG_IN_CHUNK(FIRST, NEXT, PTR) \
+ if (!ret) \
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
+ (void *)(PTR), \
+ offsetof(struct user_regs_struct, FIRST), \
+ offsetof(struct user_regs_struct, NEXT));
+
+#define REG_IN_ONE(LOC, PTR) \
+ if (!ret) \
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
+ (void *)(PTR), \
+ offsetof(struct user_regs_struct, LOC), \
+ offsetof(struct user_regs_struct, LOC) + 4);
+
+#define REG_IGNORE_ONE(LOC) \
+ if (!ret) \
+ user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
+ offsetof(struct user_regs_struct, LOC), \
+ offsetof(struct user_regs_struct, LOC) + 4);
+
+ REG_IGNORE_ONE(pad);
+
+ REG_IN_ONE(scratch.bta, &ptregs->bta);
+ REG_IN_ONE(scratch.lp_start, &ptregs->lp_start);
+ REG_IN_ONE(scratch.lp_end, &ptregs->lp_end);
+ REG_IN_ONE(scratch.lp_count, &ptregs->lp_count);
+
+ REG_IGNORE_ONE(scratch.status32);
+
+ REG_IN_ONE(scratch.ret, &ptregs->ret);
+ REG_IN_ONE(scratch.blink, &ptregs->blink);
+ REG_IN_ONE(scratch.fp, &ptregs->fp);
+ REG_IN_ONE(scratch.gp, &ptregs->r26);
+ REG_IN_ONE(scratch.r12, &ptregs->r12);
+ REG_IN_ONE(scratch.r11, &ptregs->r11);
+ REG_IN_ONE(scratch.r10, &ptregs->r10);
+ REG_IN_ONE(scratch.r9, &ptregs->r9);
+ REG_IN_ONE(scratch.r8, &ptregs->r8);
+ REG_IN_ONE(scratch.r7, &ptregs->r7);
+ REG_IN_ONE(scratch.r6, &ptregs->r6);
+ REG_IN_ONE(scratch.r5, &ptregs->r5);
+ REG_IN_ONE(scratch.r4, &ptregs->r4);
+ REG_IN_ONE(scratch.r3, &ptregs->r3);
+ REG_IN_ONE(scratch.r2, &ptregs->r2);
+ REG_IN_ONE(scratch.r1, &ptregs->r1);
+ REG_IN_ONE(scratch.r0, &ptregs->r0);
+ REG_IN_ONE(scratch.sp, &ptregs->sp);
+
+ REG_IGNORE_ONE(pad2);
+
+ REG_IN_ONE(callee.r25, &cregs->r25);
+ REG_IN_ONE(callee.r24, &cregs->r24);
+ REG_IN_ONE(callee.r23, &cregs->r23);
+ REG_IN_ONE(callee.r22, &cregs->r22);
+ REG_IN_ONE(callee.r21, &cregs->r21);
+ REG_IN_ONE(callee.r20, &cregs->r20);
+ REG_IN_ONE(callee.r19, &cregs->r19);
+ REG_IN_ONE(callee.r18, &cregs->r18);
+ REG_IN_ONE(callee.r17, &cregs->r17);
+ REG_IN_ONE(callee.r16, &cregs->r16);
+ REG_IN_ONE(callee.r15, &cregs->r15);
+ REG_IN_ONE(callee.r14, &cregs->r14);
+ REG_IN_ONE(callee.r13, &cregs->r13);
+
+ REG_IGNORE_ONE(efa); /* efa update invalid */
+ REG_IGNORE_ONE(stop_pc); /* PC updated via @ret */
+
+ return ret;
+}
+
+#ifdef CONFIG_ISA_ARCV2
+static int arcv2regs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ const struct pt_regs *regs = task_pt_regs(target);
+
+ if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS))
+ /*
+ * itemized copy not needed like above as layout of regs (r30,r58,r59)
+ * is exactly same in kernel (pt_regs) and userspace (user_regs_arcv2)
+ */
+ return membuf_write(&to, &regs->r30, sizeof(struct user_regs_arcv2));
+
+
+ membuf_write(&to, &regs->r30, 4); /* r30 only */
+ return membuf_zero(&to, sizeof(struct user_regs_arcv2) - 4);
+}
+
+static int arcv2regs_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ const struct pt_regs *regs = task_pt_regs(target);
+ int ret, copy_sz;
+
+ if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS))
+ copy_sz = sizeof(struct user_regs_arcv2);
+ else
+ copy_sz = 4; /* r30 only */
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, (void *)&regs->r30,
+ 0, copy_sz);
+
+ return ret;
+}
+
+#endif
+
+enum arc_getset {
+ REGSET_CMN,
+ REGSET_ARCV2,
+};
+
+static const struct user_regset arc_regsets[] = {
+ [REGSET_CMN] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(unsigned long),
+ .align = sizeof(unsigned long),
+ .regset_get = genregs_get,
+ .set = genregs_set,
+ },
+#ifdef CONFIG_ISA_ARCV2
+ [REGSET_ARCV2] = {
+ .core_note_type = NT_ARC_V2,
+ .n = ELF_ARCV2REG,
+ .size = sizeof(unsigned long),
+ .align = sizeof(unsigned long),
+ .regset_get = arcv2regs_get,
+ .set = arcv2regs_set,
+ },
+#endif
+};
+
+static const struct user_regset_view user_arc_view = {
+ .name = "arc",
+ .e_machine = EM_ARC_INUSE,
+ .regsets = arc_regsets,
+ .n = ARRAY_SIZE(arc_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &user_arc_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int ret = -EIO;
+
+ pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data);
+
+ switch (request) {
+ case PTRACE_GET_THREAD_AREA:
+ ret = put_user(task_thread_info(child)->thr_ptr,
+ (unsigned long __user *)data);
+ break;
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ if (ptrace_report_syscall_entry(regs))
+ return ULONG_MAX;
+
+#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_enter(regs, syscall_get_nr(current, regs));
+#endif
+
+ return regs->r8;
+}
+
+asmlinkage void syscall_trace_exit(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACE))
+ ptrace_report_syscall_exit(regs, 0);
+
+#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
+ if (test_thread_flag(TIF_SYSCALL_TRACEPOINT))
+ trace_sys_exit(regs, regs_return_value(regs));
+#endif
+}
+
+int regs_query_register_offset(const char *name)
+{
+ const struct pt_regs_offset *roff;
+
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (!strcmp(roff->name, name))
+ return roff->offset;
+ return -EINVAL;
+}
+
+const char *regs_query_register_name(unsigned int offset)
+{
+ const struct pt_regs_offset *roff;
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (roff->offset == offset)
+ return roff->name;
+ return NULL;
+}
+
+bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
+{
+ return (addr & ~(THREAD_SIZE - 1)) ==
+ (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
+}
+
+unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
+{
+ unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
+
+ addr += n;
+ if (regs_within_kernel_stack(regs, (unsigned long)addr))
+ return *addr;
+ else
+ return 0;
+}
diff --git a/arch/arc/kernel/reset.c b/arch/arc/kernel/reset.c
new file mode 100644
index 0000000000..fd6c3eb930
--- /dev/null
+++ b/arch/arc/kernel/reset.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/printk.h>
+#include <linux/reboot.h>
+#include <linux/pm.h>
+
+void machine_halt(void)
+{
+ /* Halt the processor */
+ __asm__ __volatile__("flag 1\n");
+}
+
+void machine_restart(char *__unused)
+{
+ /* Soft reset : jump to reset vector */
+ pr_info("Put your restart handler here\n");
+ machine_halt();
+}
+
+void machine_power_off(void)
+{
+ /* FIXME :: power off ??? */
+ machine_halt();
+}
+
+void (*pm_power_off) (void) = NULL;
+EXPORT_SYMBOL(pm_power_off);
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
new file mode 100644
index 0000000000..d08a5092c2
--- /dev/null
+++ b/arch/arc/kernel/setup.c
@@ -0,0 +1,654 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/seq_file.h>
+#include <linux/fs.h>
+#include <linux/delay.h>
+#include <linux/root_dev.h>
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/console.h>
+#include <linux/module.h>
+#include <linux/sizes.h>
+#include <linux/cpu.h>
+#include <linux/of_clk.h>
+#include <linux/of_fdt.h>
+#include <linux/of.h>
+#include <linux/cache.h>
+#include <uapi/linux/mount.h>
+#include <asm/sections.h>
+#include <asm/arcregs.h>
+#include <asm/asserts.h>
+#include <asm/tlb.h>
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/irq.h>
+#include <asm/unwind.h>
+#include <asm/mach_desc.h>
+#include <asm/smp.h>
+#include <asm/dsp-impl.h>
+#include <soc/arc/mcip.h>
+
+#define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x))
+
+unsigned int intr_to_DE_cnt;
+
+/* Part of U-boot ABI: see head.S */
+int __initdata uboot_tag;
+int __initdata uboot_magic;
+char __initdata *uboot_arg;
+
+const struct machine_desc *machine_desc;
+
+struct task_struct *_current_task[NR_CPUS]; /* For stack switching */
+
+struct cpuinfo_arc {
+ int arcver;
+ unsigned int t0:1, t1:1;
+ struct {
+ unsigned long base;
+ unsigned int sz;
+ } iccm, dccm;
+};
+
+#ifdef CONFIG_ISA_ARCV2
+
+static const struct id_to_str arc_hs_rel[] = {
+ /* ID.ARCVER, Release */
+ { 0x51, "R2.0" },
+ { 0x52, "R2.1" },
+ { 0x53, "R3.0" },
+};
+
+static const struct id_to_str arc_hs_ver54_rel[] = {
+ /* UARCH.MAJOR, Release */
+ { 0, "R3.10a"},
+ { 1, "R3.50a"},
+ { 2, "R3.60a"},
+ { 3, "R4.00a"},
+ { 0xFF, NULL }
+};
+#endif
+
+static int
+arcompact_mumbojumbo(int c, struct cpuinfo_arc *info, char *buf, int len)
+{
+ int n = 0;
+#ifdef CONFIG_ISA_ARCOMPACT
+ char *cpu_nm, *isa_nm = "ARCompact";
+ struct bcr_fp_arcompact fpu_sp, fpu_dp;
+ int atomic = 0, be, present;
+ int bpu_full, bpu_cache, bpu_pred;
+ struct bcr_bpu_arcompact bpu;
+ struct bcr_iccm_arcompact iccm;
+ struct bcr_dccm_arcompact dccm;
+ struct bcr_generic isa;
+
+ READ_BCR(ARC_REG_ISA_CFG_BCR, isa);
+
+ if (!isa.ver) /* ISA BCR absent, use Kconfig info */
+ atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC);
+ else {
+ /* ARC700_BUILD only has 2 bits of isa info */
+ atomic = isa.info & 1;
+ }
+
+ be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN);
+
+ if (info->arcver < 0x34)
+ cpu_nm = "ARC750";
+ else
+ cpu_nm = "ARC770";
+
+ n += scnprintf(buf + n, len - n, "processor [%d]\t: %s (%s ISA) %s%s%s\n",
+ c, cpu_nm, isa_nm,
+ IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
+ IS_AVAIL1(be, "[Big-Endian]"));
+
+ READ_BCR(ARC_REG_FP_BCR, fpu_sp);
+ READ_BCR(ARC_REG_DPFP_BCR, fpu_dp);
+
+ if (fpu_sp.ver | fpu_dp.ver)
+ n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n",
+ IS_AVAIL1(fpu_sp.ver, "SP "),
+ IS_AVAIL1(fpu_dp.ver, "DP "));
+
+ READ_BCR(ARC_REG_BPU_BCR, bpu);
+ bpu_full = bpu.fam ? 1 : 0;
+ bpu_cache = 256 << (bpu.ent - 1);
+ bpu_pred = 256 << (bpu.ent - 1);
+
+ n += scnprintf(buf + n, len - n,
+ "BPU\t\t: %s%s match, cache:%d, Predict Table:%d\n",
+ IS_AVAIL1(bpu_full, "full"),
+ IS_AVAIL1(!bpu_full, "partial"),
+ bpu_cache, bpu_pred);
+
+ READ_BCR(ARC_REG_ICCM_BUILD, iccm);
+ if (iccm.ver) {
+ info->iccm.sz = 4096 << iccm.sz; /* 8K to 512K */
+ info->iccm.base = iccm.base << 16;
+ }
+
+ READ_BCR(ARC_REG_DCCM_BUILD, dccm);
+ if (dccm.ver) {
+ unsigned long base;
+ info->dccm.sz = 2048 << dccm.sz; /* 2K to 256K */
+
+ base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD);
+ info->dccm.base = base & ~0xF;
+ }
+
+ /* ARCompact ISA specific sanity checks */
+ present = fpu_dp.ver; /* SP has no arch visible regs */
+ CHK_OPT_STRICT(CONFIG_ARC_FPU_SAVE_RESTORE, present);
+#endif
+ return n;
+
+}
+
+static int arcv2_mumbojumbo(int c, struct cpuinfo_arc *info, char *buf, int len)
+{
+ int n = 0;
+#ifdef CONFIG_ISA_ARCV2
+ const char *release = "", *cpu_nm = "HS38", *isa_nm = "ARCv2";
+ int dual_issue = 0, dual_enb = 0, mpy_opt, present;
+ int bpu_full, bpu_cache, bpu_pred, bpu_ret_stk;
+ char mpy_nm[16], lpb_nm[32];
+ struct bcr_isa_arcv2 isa;
+ struct bcr_mpy mpy;
+ struct bcr_fp_arcv2 fpu;
+ struct bcr_bpu_arcv2 bpu;
+ struct bcr_lpb lpb;
+ struct bcr_iccm_arcv2 iccm;
+ struct bcr_dccm_arcv2 dccm;
+ struct bcr_erp erp;
+
+ /*
+ * Initial HS cores bumped AUX IDENTITY.ARCVER for each release until
+ * ARCVER 0x54 which introduced AUX MICRO_ARCH_BUILD and subsequent
+ * releases only update it.
+ */
+
+ if (info->arcver > 0x50 && info->arcver <= 0x53) {
+ release = arc_hs_rel[info->arcver - 0x51].str;
+ } else {
+ const struct id_to_str *tbl;
+ struct bcr_uarch_build uarch;
+
+ READ_BCR(ARC_REG_MICRO_ARCH_BCR, uarch);
+
+ for (tbl = &arc_hs_ver54_rel[0]; tbl->id != 0xFF; tbl++) {
+ if (uarch.maj == tbl->id) {
+ release = tbl->str;
+ break;
+ }
+ }
+ if (uarch.prod == 4) {
+ unsigned int exec_ctrl;
+
+ cpu_nm = "HS48";
+ dual_issue = 1;
+ /* if dual issue hardware, is it enabled ? */
+ READ_BCR(AUX_EXEC_CTRL, exec_ctrl);
+ dual_enb = !(exec_ctrl & 1);
+ }
+ }
+
+ READ_BCR(ARC_REG_ISA_CFG_BCR, isa);
+
+ n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s%s%s\n",
+ c, cpu_nm, release, isa_nm,
+ IS_AVAIL1(isa.be, "[Big-Endian]"),
+ IS_AVAIL3(dual_issue, dual_enb, " Dual-Issue "));
+
+ READ_BCR(ARC_REG_MPY_BCR, mpy);
+ mpy_opt = 2; /* stock MPY/MPYH */
+ if (mpy.dsp) /* OPT 7-9 */
+ mpy_opt = mpy.dsp + 6;
+
+ scnprintf(mpy_nm, 16, "mpy[opt %d] ", mpy_opt);
+
+ READ_BCR(ARC_REG_FP_V2_BCR, fpu);
+
+ n += scnprintf(buf + n, len - n, "ISA Extn\t: %s%s%s%s%s%s%s%s%s%s%s\n",
+ IS_AVAIL2(isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC),
+ IS_AVAIL2(isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64),
+ IS_AVAIL2(isa.unalign, "unalign ", CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS),
+ IS_AVAIL1(mpy.ver, mpy_nm),
+ IS_AVAIL1(isa.div_rem, "div_rem "),
+ IS_AVAIL1((fpu.sp | fpu.dp), " FPU:"),
+ IS_AVAIL1(fpu.sp, " sp"),
+ IS_AVAIL1(fpu.dp, " dp"));
+
+ READ_BCR(ARC_REG_BPU_BCR, bpu);
+ bpu_full = bpu.ft;
+ bpu_cache = 256 << bpu.bce;
+ bpu_pred = 2048 << bpu.pte;
+ bpu_ret_stk = 4 << bpu.rse;
+
+ READ_BCR(ARC_REG_LPB_BUILD, lpb);
+ if (lpb.ver) {
+ unsigned int ctl;
+ ctl = read_aux_reg(ARC_REG_LPB_CTRL);
+
+ scnprintf(lpb_nm, sizeof(lpb_nm), " Loop Buffer:%d %s",
+ lpb.entries, IS_DISABLED_RUN(!ctl));
+ }
+
+ n += scnprintf(buf + n, len - n,
+ "BPU\t\t: %s%s match, cache:%d, Predict Table:%d Return stk: %d%s\n",
+ IS_AVAIL1(bpu_full, "full"),
+ IS_AVAIL1(!bpu_full, "partial"),
+ bpu_cache, bpu_pred, bpu_ret_stk,
+ lpb_nm);
+
+ READ_BCR(ARC_REG_ICCM_BUILD, iccm);
+ if (iccm.ver) {
+ unsigned long base;
+ info->iccm.sz = 256 << iccm.sz00; /* 512B to 16M */
+ if (iccm.sz00 == 0xF && iccm.sz01 > 0)
+ info->iccm.sz <<= iccm.sz01;
+ base = read_aux_reg(ARC_REG_AUX_ICCM);
+ info->iccm.base = base & 0xF0000000;
+ }
+
+ READ_BCR(ARC_REG_DCCM_BUILD, dccm);
+ if (dccm.ver) {
+ unsigned long base;
+ info->dccm.sz = 256 << dccm.sz0;
+ if (dccm.sz0 == 0xF && dccm.sz1 > 0)
+ info->dccm.sz <<= dccm.sz1;
+ base = read_aux_reg(ARC_REG_AUX_DCCM);
+ info->dccm.base = base & 0xF0000000;
+ }
+
+ /* Error Protection: ECC/Parity */
+ READ_BCR(ARC_REG_ERP_BUILD, erp);
+ if (erp.ver) {
+ struct ctl_erp ctl;
+ READ_BCR(ARC_REG_ERP_CTRL, ctl);
+ /* inverted bits: 0 means enabled */
+ n += scnprintf(buf + n, len - n, "Extn [ECC]\t: %s%s%s%s%s%s\n",
+ IS_AVAIL3(erp.ic, !ctl.dpi, "IC "),
+ IS_AVAIL3(erp.dc, !ctl.dpd, "DC "),
+ IS_AVAIL3(erp.mmu, !ctl.mpd, "MMU "));
+ }
+
+ /* ARCv2 ISA specific sanity checks */
+ present = fpu.sp | fpu.dp | mpy.dsp; /* DSP and/or FPU */
+ CHK_OPT_STRICT(CONFIG_ARC_HAS_ACCL_REGS, present);
+
+ dsp_config_check();
+#endif
+ return n;
+}
+
+static char *arc_cpu_mumbojumbo(int c, struct cpuinfo_arc *info, char *buf, int len)
+{
+ struct bcr_identity ident;
+ struct bcr_timer timer;
+ struct bcr_generic bcr;
+ struct mcip_bcr mp;
+ struct bcr_actionpoint ap;
+ unsigned long vec_base;
+ int ap_num, ap_full, smart, rtt, n;
+
+ memset(info, 0, sizeof(struct cpuinfo_arc));
+
+ READ_BCR(AUX_IDENTITY, ident);
+ info->arcver = ident.family;
+
+ n = scnprintf(buf, len,
+ "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n",
+ ident.family, ident.cpu_id, ident.chip_id);
+
+ if (is_isa_arcompact()) {
+ n += arcompact_mumbojumbo(c, info, buf + n, len - n);
+ } else if (is_isa_arcv2()){
+ n += arcv2_mumbojumbo(c, info, buf + n, len - n);
+ }
+
+ n += arc_mmu_mumbojumbo(c, buf + n, len - n);
+ n += arc_cache_mumbojumbo(c, buf + n, len - n);
+
+ READ_BCR(ARC_REG_TIMERS_BCR, timer);
+ info->t0 = timer.t0;
+ info->t1 = timer.t1;
+
+ READ_BCR(ARC_REG_MCIP_BCR, mp);
+ vec_base = read_aux_reg(AUX_INTR_VEC_BASE);
+
+ n += scnprintf(buf + n, len - n,
+ "Timers\t\t: %s%s%s%s%s%s\nVector Table\t: %#lx\n",
+ IS_AVAIL1(timer.t0, "Timer0 "),
+ IS_AVAIL1(timer.t1, "Timer1 "),
+ IS_AVAIL2(timer.rtc, "RTC [UP 64-bit] ", CONFIG_ARC_TIMERS_64BIT),
+ IS_AVAIL2(mp.gfrc, "GFRC [SMP 64-bit] ", CONFIG_ARC_TIMERS_64BIT),
+ vec_base);
+
+ READ_BCR(ARC_REG_AP_BCR, ap);
+ if (ap.ver) {
+ ap_num = 2 << ap.num;
+ ap_full = !ap.min;
+ }
+
+ READ_BCR(ARC_REG_SMART_BCR, bcr);
+ smart = bcr.ver ? 1 : 0;
+
+ READ_BCR(ARC_REG_RTT_BCR, bcr);
+ rtt = bcr.ver ? 1 : 0;
+
+ if (ap.ver | smart | rtt) {
+ n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s",
+ IS_AVAIL1(smart, "smaRT "),
+ IS_AVAIL1(rtt, "RTT "));
+ if (ap.ver) {
+ n += scnprintf(buf + n, len - n, "ActionPoint %d/%s",
+ ap_num,
+ ap_full ? "full":"min");
+ }
+ n += scnprintf(buf + n, len - n, "\n");
+ }
+
+ if (info->dccm.sz || info->iccm.sz)
+ n += scnprintf(buf + n, len - n,
+ "Extn [CCM]\t: DCCM @ %lx, %d KB / ICCM: @ %lx, %d KB\n",
+ info->dccm.base, TO_KB(info->dccm.sz),
+ info->iccm.base, TO_KB(info->iccm.sz));
+
+ return buf;
+}
+
+void chk_opt_strict(char *opt_name, bool hw_exists, bool opt_ena)
+{
+ if (hw_exists && !opt_ena)
+ pr_warn(" ! Enable %s for working apps\n", opt_name);
+ else if (!hw_exists && opt_ena)
+ panic("Disable %s, hardware NOT present\n", opt_name);
+}
+
+void chk_opt_weak(char *opt_name, bool hw_exists, bool opt_ena)
+{
+ if (!hw_exists && opt_ena)
+ panic("Disable %s, hardware NOT present\n", opt_name);
+}
+
+/*
+ * ISA agnostic sanity checks
+ */
+static void arc_chk_core_config(struct cpuinfo_arc *info)
+{
+ if (!info->t0)
+ panic("Timer0 is not present!\n");
+
+ if (!info->t1)
+ panic("Timer1 is not present!\n");
+
+#ifdef CONFIG_ARC_HAS_DCCM
+ /*
+ * DCCM can be arbit placed in hardware.
+ * Make sure it's placement/sz matches what Linux is built with
+ */
+ if ((unsigned int)__arc_dccm_base != info->dccm.base)
+ panic("Linux built with incorrect DCCM Base address\n");
+
+ if (CONFIG_ARC_DCCM_SZ * SZ_1K != info->dccm.sz)
+ panic("Linux built with incorrect DCCM Size\n");
+#endif
+
+#ifdef CONFIG_ARC_HAS_ICCM
+ if (CONFIG_ARC_ICCM_SZ * SZ_1K != info->iccm.sz)
+ panic("Linux built with incorrect ICCM Size\n");
+#endif
+}
+
+/*
+ * Initialize and setup the processor core
+ * This is called by all the CPUs thus should not do special case stuff
+ * such as only for boot CPU etc
+ */
+
+void setup_processor(void)
+{
+ struct cpuinfo_arc info;
+ int c = smp_processor_id();
+ char str[512];
+
+ pr_info("%s", arc_cpu_mumbojumbo(c, &info, str, sizeof(str)));
+ pr_info("%s", arc_platform_smp_cpuinfo());
+
+ arc_chk_core_config(&info);
+
+ arc_init_IRQ();
+ arc_mmu_init();
+ arc_cache_init();
+
+}
+
+static inline bool uboot_arg_invalid(unsigned long addr)
+{
+ /*
+ * Check that it is a untranslated address (although MMU is not enabled
+ * yet, it being a high address ensures this is not by fluke)
+ */
+ if (addr < PAGE_OFFSET)
+ return true;
+
+ /* Check that address doesn't clobber resident kernel image */
+ return addr >= (unsigned long)_stext && addr <= (unsigned long)_end;
+}
+
+#define IGNORE_ARGS "Ignore U-boot args: "
+
+/* uboot_tag values for U-boot - kernel ABI revision 0; see head.S */
+#define UBOOT_TAG_NONE 0
+#define UBOOT_TAG_CMDLINE 1
+#define UBOOT_TAG_DTB 2
+/* We always pass 0 as magic from U-boot */
+#define UBOOT_MAGIC_VALUE 0
+
+void __init handle_uboot_args(void)
+{
+ bool use_embedded_dtb = true;
+ bool append_cmdline = false;
+
+ /* check that we know this tag */
+ if (uboot_tag != UBOOT_TAG_NONE &&
+ uboot_tag != UBOOT_TAG_CMDLINE &&
+ uboot_tag != UBOOT_TAG_DTB) {
+ pr_warn(IGNORE_ARGS "invalid uboot tag: '%08x'\n", uboot_tag);
+ goto ignore_uboot_args;
+ }
+
+ if (uboot_magic != UBOOT_MAGIC_VALUE) {
+ pr_warn(IGNORE_ARGS "non zero uboot magic\n");
+ goto ignore_uboot_args;
+ }
+
+ if (uboot_tag != UBOOT_TAG_NONE &&
+ uboot_arg_invalid((unsigned long)uboot_arg)) {
+ pr_warn(IGNORE_ARGS "invalid uboot arg: '%px'\n", uboot_arg);
+ goto ignore_uboot_args;
+ }
+
+ /* see if U-boot passed an external Device Tree blob */
+ if (uboot_tag == UBOOT_TAG_DTB) {
+ machine_desc = setup_machine_fdt((void *)uboot_arg);
+
+ /* external Device Tree blob is invalid - use embedded one */
+ use_embedded_dtb = !machine_desc;
+ }
+
+ if (uboot_tag == UBOOT_TAG_CMDLINE)
+ append_cmdline = true;
+
+ignore_uboot_args:
+
+ if (use_embedded_dtb) {
+ machine_desc = setup_machine_fdt(__dtb_start);
+ if (!machine_desc)
+ panic("Embedded DT invalid\n");
+ }
+
+ /*
+ * NOTE: @boot_command_line is populated by setup_machine_fdt() so this
+ * append processing can only happen after.
+ */
+ if (append_cmdline) {
+ /* Ensure a whitespace between the 2 cmdlines */
+ strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
+ strlcat(boot_command_line, uboot_arg, COMMAND_LINE_SIZE);
+ }
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+ handle_uboot_args();
+
+ /* Save unparsed command line copy for /proc/cmdline */
+ *cmdline_p = boot_command_line;
+
+ /* To force early parsing of things like mem=xxx */
+ parse_early_param();
+
+ /* Platform/board specific: e.g. early console registration */
+ if (machine_desc->init_early)
+ machine_desc->init_early();
+
+ smp_init_cpus();
+
+ setup_processor();
+ setup_arch_memory();
+
+ /* copy flat DT out of .init and then unflatten it */
+ unflatten_and_copy_device_tree();
+
+ /* Can be issue if someone passes cmd line arg "ro"
+ * But that is unlikely so keeping it as it is
+ */
+ root_mountflags &= ~MS_RDONLY;
+
+ arc_unwind_init();
+}
+
+/*
+ * Called from start_kernel() - boot CPU only
+ */
+void __init time_init(void)
+{
+ of_clk_init(NULL);
+ timer_probe();
+}
+
+static int __init customize_machine(void)
+{
+ if (machine_desc->init_machine)
+ machine_desc->init_machine();
+
+ return 0;
+}
+arch_initcall(customize_machine);
+
+static int __init init_late_machine(void)
+{
+ if (machine_desc->init_late)
+ machine_desc->init_late();
+
+ return 0;
+}
+late_initcall(init_late_machine);
+/*
+ * Get CPU information for use by the procfs.
+ */
+
+#define cpu_to_ptr(c) ((void *)(0xFFFF0000 | (unsigned int)(c)))
+#define ptr_to_cpu(p) (~0xFFFF0000UL & (unsigned int)(p))
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+ char *str;
+ int cpu_id = ptr_to_cpu(v);
+ struct device *cpu_dev = get_cpu_device(cpu_id);
+ struct cpuinfo_arc info;
+ struct clk *cpu_clk;
+ unsigned long freq = 0;
+
+ if (!cpu_online(cpu_id)) {
+ seq_printf(m, "processor [%d]\t: Offline\n", cpu_id);
+ goto done;
+ }
+
+ str = (char *)__get_free_page(GFP_KERNEL);
+ if (!str)
+ goto done;
+
+ seq_printf(m, arc_cpu_mumbojumbo(cpu_id, &info, str, PAGE_SIZE));
+
+ cpu_clk = clk_get(cpu_dev, NULL);
+ if (IS_ERR(cpu_clk)) {
+ seq_printf(m, "CPU speed \t: Cannot get clock for processor [%d]\n",
+ cpu_id);
+ } else {
+ freq = clk_get_rate(cpu_clk);
+ }
+ if (freq)
+ seq_printf(m, "CPU speed\t: %lu.%02lu Mhz\n",
+ freq / 1000000, (freq / 10000) % 100);
+
+ seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n",
+ loops_per_jiffy / (500000 / HZ),
+ (loops_per_jiffy / (5000 / HZ)) % 100);
+
+ seq_printf(m, arc_platform_smp_cpuinfo());
+
+ free_page((unsigned long)str);
+done:
+ seq_printf(m, "\n");
+
+ return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ /*
+ * Callback returns cpu-id to iterator for show routine, NULL to stop.
+ * However since NULL is also a valid cpu-id (0), we use a round-about
+ * way to pass it w/o having to kmalloc/free a 2 byte string.
+ * Encode cpu-id as 0xFFcccc, which is decoded by show routine.
+ */
+ return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ ++*pos;
+ return c_start(m, pos);
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+ .start = c_start,
+ .next = c_next,
+ .stop = c_stop,
+ .show = show_cpuinfo
+};
+
+static DEFINE_PER_CPU(struct cpu, cpu_topology);
+
+static int __init topology_init(void)
+{
+ int cpu;
+
+ for_each_present_cpu(cpu)
+ register_cpu(&per_cpu(cpu_topology, cpu), cpu);
+
+ return 0;
+}
+
+subsys_initcall(topology_init);
diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c
new file mode 100644
index 0000000000..8f6f4a5429
--- /dev/null
+++ b/arch/arc/kernel/signal.c
@@ -0,0 +1,443 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Signal Handling for ARC
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * vineetg: Jan 2010 (Restarting of timer related syscalls)
+ *
+ * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK)
+ * -do_signal() supports TIF_RESTORE_SIGMASK
+ * -do_signal() no loner needs oldset, required by OLD sys_sigsuspend
+ * -sys_rt_sigsuspend() now comes from generic code, so discard arch implemen
+ * -sys_sigsuspend() no longer needs to fudge ptregs, hence that arg removed
+ * -sys_sigsuspend() no longer loops for do_signal(), sets TIF_xxx and leaves
+ * the job to do_signal()
+ *
+ * vineetg: July 2009
+ * -Modified Code to support the uClibc provided userland sigreturn stub
+ * to avoid kernel synthesing it on user stack at runtime, costing TLB
+ * probes and Cache line flushes.
+ *
+ * vineetg: July 2009
+ * -In stash_usr_regs( ) and restore_usr_regs( ), save/restore of user regs
+ * in done in block copy rather than one word at a time.
+ * This saves around 2K of code and improves LMBench lat_sig <catch>
+ *
+ * rajeshwarr: Feb 2009
+ * - Support for Realtime Signals
+ *
+ * vineetg: Aug 11th 2008: Bug #94183
+ * -ViXS were still seeing crashes when using insmod to load drivers.
+ * It turned out that the code to change Execute permssions for TLB entries
+ * of user was not guarded for interrupts (mod_tlb_permission)
+ * This was causing TLB entries to be overwritten on unrelated indexes
+ *
+ * Vineetg: July 15th 2008: Bug #94183
+ * -Exception happens in Delay slot of a JMP, and before user space resumes,
+ * Signal is delivered (Ctrl + C) = >SIGINT.
+ * setup_frame( ) sets up PC,SP,BLINK to enable user space signal handler
+ * to run, but doesn't clear the Delay slot bit from status32. As a result,
+ * on resuming user mode, signal handler branches off to BTA of orig JMP
+ * -FIX: clear the DE bit from status32 in setup_frame( )
+ *
+ * Rahul Trivedi, Kanika Nema: Codito Technologies 2004
+ */
+
+#include <linux/signal.h>
+#include <linux/ptrace.h>
+#include <linux/personality.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+#include <linux/resume_user_mode.h>
+#include <linux/sched/task_stack.h>
+
+#include <asm/ucontext.h>
+#include <asm/entry.h>
+
+struct rt_sigframe {
+ struct siginfo info;
+ struct ucontext uc;
+#define MAGIC_SIGALTSTK 0x07302004
+ unsigned int sigret_magic;
+};
+
+static int save_arcv2_regs(struct sigcontext __user *mctx, struct pt_regs *regs)
+{
+ int err = 0;
+#ifndef CONFIG_ISA_ARCOMPACT
+ struct user_regs_arcv2 v2abi;
+
+ v2abi.r30 = regs->r30;
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+ v2abi.r58 = regs->r58;
+ v2abi.r59 = regs->r59;
+#else
+ v2abi.r58 = v2abi.r59 = 0;
+#endif
+ err = __copy_to_user(&mctx->v2abi, (void const *)&v2abi, sizeof(v2abi));
+#endif
+ return err;
+}
+
+static int restore_arcv2_regs(struct sigcontext __user *mctx, struct pt_regs *regs)
+{
+ int err = 0;
+#ifndef CONFIG_ISA_ARCOMPACT
+ struct user_regs_arcv2 v2abi;
+
+ err = __copy_from_user(&v2abi, &mctx->v2abi, sizeof(v2abi));
+
+ regs->r30 = v2abi.r30;
+#ifdef CONFIG_ARC_HAS_ACCL_REGS
+ regs->r58 = v2abi.r58;
+ regs->r59 = v2abi.r59;
+#endif
+#endif
+ return err;
+}
+
+static int
+stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs,
+ sigset_t *set)
+{
+ int err;
+ struct user_regs_struct uregs;
+
+ uregs.scratch.bta = regs->bta;
+ uregs.scratch.lp_start = regs->lp_start;
+ uregs.scratch.lp_end = regs->lp_end;
+ uregs.scratch.lp_count = regs->lp_count;
+ uregs.scratch.status32 = regs->status32;
+ uregs.scratch.ret = regs->ret;
+ uregs.scratch.blink = regs->blink;
+ uregs.scratch.fp = regs->fp;
+ uregs.scratch.gp = regs->r26;
+ uregs.scratch.r12 = regs->r12;
+ uregs.scratch.r11 = regs->r11;
+ uregs.scratch.r10 = regs->r10;
+ uregs.scratch.r9 = regs->r9;
+ uregs.scratch.r8 = regs->r8;
+ uregs.scratch.r7 = regs->r7;
+ uregs.scratch.r6 = regs->r6;
+ uregs.scratch.r5 = regs->r5;
+ uregs.scratch.r4 = regs->r4;
+ uregs.scratch.r3 = regs->r3;
+ uregs.scratch.r2 = regs->r2;
+ uregs.scratch.r1 = regs->r1;
+ uregs.scratch.r0 = regs->r0;
+ uregs.scratch.sp = regs->sp;
+
+ err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), &uregs.scratch,
+ sizeof(sf->uc.uc_mcontext.regs.scratch));
+
+ if (is_isa_arcv2())
+ err |= save_arcv2_regs(&(sf->uc.uc_mcontext), regs);
+
+ err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t));
+
+ return err ? -EFAULT : 0;
+}
+
+static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf)
+{
+ sigset_t set;
+ int err;
+ struct user_regs_struct uregs;
+
+ err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
+ err |= __copy_from_user(&uregs.scratch,
+ &(sf->uc.uc_mcontext.regs.scratch),
+ sizeof(sf->uc.uc_mcontext.regs.scratch));
+
+ if (is_isa_arcv2())
+ err |= restore_arcv2_regs(&(sf->uc.uc_mcontext), regs);
+
+ if (err)
+ return -EFAULT;
+
+ set_current_blocked(&set);
+ regs->bta = uregs.scratch.bta;
+ regs->lp_start = uregs.scratch.lp_start;
+ regs->lp_end = uregs.scratch.lp_end;
+ regs->lp_count = uregs.scratch.lp_count;
+ regs->status32 = uregs.scratch.status32;
+ regs->ret = uregs.scratch.ret;
+ regs->blink = uregs.scratch.blink;
+ regs->fp = uregs.scratch.fp;
+ regs->r26 = uregs.scratch.gp;
+ regs->r12 = uregs.scratch.r12;
+ regs->r11 = uregs.scratch.r11;
+ regs->r10 = uregs.scratch.r10;
+ regs->r9 = uregs.scratch.r9;
+ regs->r8 = uregs.scratch.r8;
+ regs->r7 = uregs.scratch.r7;
+ regs->r6 = uregs.scratch.r6;
+ regs->r5 = uregs.scratch.r5;
+ regs->r4 = uregs.scratch.r4;
+ regs->r3 = uregs.scratch.r3;
+ regs->r2 = uregs.scratch.r2;
+ regs->r1 = uregs.scratch.r1;
+ regs->r0 = uregs.scratch.r0;
+ regs->sp = uregs.scratch.sp;
+
+ return 0;
+}
+
+static inline int is_do_ss_needed(unsigned int magic)
+{
+ if (MAGIC_SIGALTSTK == magic)
+ return 1;
+ else
+ return 0;
+}
+
+SYSCALL_DEFINE0(rt_sigreturn)
+{
+ struct rt_sigframe __user *sf;
+ unsigned int magic;
+ struct pt_regs *regs = current_pt_regs();
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ /* Since we stacked the signal on a word boundary,
+ * then 'sp' should be word aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (regs->sp & 3)
+ goto badframe;
+
+ sf = (struct rt_sigframe __force __user *)(regs->sp);
+
+ if (!access_ok(sf, sizeof(*sf)))
+ goto badframe;
+
+ if (__get_user(magic, &sf->sigret_magic))
+ goto badframe;
+
+ if (unlikely(is_do_ss_needed(magic)))
+ if (restore_altstack(&sf->uc.uc_stack))
+ goto badframe;
+
+ if (restore_usr_regs(regs, sf))
+ goto badframe;
+
+ /* Don't restart from sigreturn */
+ syscall_wont_restart(regs);
+
+ /*
+ * Ensure that sigreturn always returns to user mode (in case the
+ * regs saved on user stack got fudged between save and sigreturn)
+ * Otherwise it is easy to panic the kernel with a custom
+ * signal handler and/or restorer which clobberes the status32/ret
+ * to return to a bogus location in kernel mode.
+ */
+ regs->status32 |= STATUS_U_MASK;
+
+ return regs->r0;
+
+badframe:
+ force_sig(SIGSEGV);
+ return 0;
+}
+
+/*
+ * Determine which stack to use..
+ */
+static inline void __user *get_sigframe(struct ksignal *ksig,
+ struct pt_regs *regs,
+ unsigned long framesize)
+{
+ unsigned long sp = sigsp(regs->sp, ksig);
+ void __user *frame;
+
+ /* No matter what happens, 'sp' must be word
+ * aligned otherwise nasty things could happen
+ */
+
+ /* ATPCS B01 mandates 8-byte alignment */
+ frame = (void __user *)((sp - framesize) & ~7);
+
+ /* Check that we can actually write to the signal frame */
+ if (!access_ok(frame, framesize))
+ frame = NULL;
+
+ return frame;
+}
+
+static int
+setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs)
+{
+ struct rt_sigframe __user *sf;
+ unsigned int magic = 0;
+ int err = 0;
+
+ sf = get_sigframe(ksig, regs, sizeof(struct rt_sigframe));
+ if (!sf)
+ return 1;
+
+ /*
+ * w/o SA_SIGINFO, struct ucontext is partially populated (only
+ * uc_mcontext/uc_sigmask) for kernel's normal user state preservation
+ * during signal handler execution. This works for SA_SIGINFO as well
+ * although the semantics are now overloaded (the same reg state can be
+ * inspected by userland: but are they allowed to fiddle with it ?
+ */
+ err |= stash_usr_regs(sf, regs, set);
+
+ /*
+ * SA_SIGINFO requires 3 args to signal handler:
+ * #1: sig-no (common to any handler)
+ * #2: struct siginfo
+ * #3: struct ucontext (completely populated)
+ */
+ if (unlikely(ksig->ka.sa.sa_flags & SA_SIGINFO)) {
+ err |= copy_siginfo_to_user(&sf->info, &ksig->info);
+ err |= __put_user(0, &sf->uc.uc_flags);
+ err |= __put_user(NULL, &sf->uc.uc_link);
+ err |= __save_altstack(&sf->uc.uc_stack, regs->sp);
+
+ /* setup args 2 and 3 for user mode handler */
+ regs->r1 = (unsigned long)&sf->info;
+ regs->r2 = (unsigned long)&sf->uc;
+
+ /*
+ * small optim to avoid unconditionally calling do_sigaltstack
+ * in sigreturn path, now that we only have rt_sigreturn
+ */
+ magic = MAGIC_SIGALTSTK;
+ }
+
+ err |= __put_user(magic, &sf->sigret_magic);
+ if (err)
+ return err;
+
+ /* #1 arg to the user Signal handler */
+ regs->r0 = ksig->sig;
+
+ /* setup PC of user space signal handler */
+ regs->ret = (unsigned long)ksig->ka.sa.sa_handler;
+
+ /*
+ * handler returns using sigreturn stub provided already by userspace
+ * If not, nuke the process right away
+ */
+ if(!(ksig->ka.sa.sa_flags & SA_RESTORER))
+ return 1;
+
+ regs->blink = (unsigned long)ksig->ka.sa.sa_restorer;
+
+ /* User Stack for signal handler will be above the frame just carved */
+ regs->sp = (unsigned long)sf;
+
+ /*
+ * Bug 94183, Clear the DE bit, so that when signal handler
+ * starts to run, it doesn't use BTA
+ */
+ regs->status32 &= ~STATUS_DE_MASK;
+ regs->status32 |= STATUS_L_MASK;
+
+ return err;
+}
+
+static void arc_restart_syscall(struct k_sigaction *ka, struct pt_regs *regs)
+{
+ switch (regs->r0) {
+ case -ERESTART_RESTARTBLOCK:
+ case -ERESTARTNOHAND:
+ /*
+ * ERESTARTNOHAND means that the syscall should
+ * only be restarted if there was no handler for
+ * the signal, and since we only get here if there
+ * is a handler, we don't restart
+ */
+ regs->r0 = -EINTR; /* ERESTART_xxx is internal */
+ break;
+
+ case -ERESTARTSYS:
+ /*
+ * ERESTARTSYS means to restart the syscall if
+ * there is no handler or the handler was
+ * registered with SA_RESTART
+ */
+ if (!(ka->sa.sa_flags & SA_RESTART)) {
+ regs->r0 = -EINTR;
+ break;
+ }
+ fallthrough;
+
+ case -ERESTARTNOINTR:
+ /*
+ * ERESTARTNOINTR means that the syscall should
+ * be called again after the signal handler returns.
+ * Setup reg state just as it was before doing the trap
+ * r0 has been clobbered with sys call ret code thus it
+ * needs to be reloaded with orig first arg to syscall
+ * in orig_r0. Rest of relevant reg-file:
+ * r8 (syscall num) and (r1 - r7) will be reset to
+ * their orig user space value when we ret from kernel
+ */
+ regs->r0 = regs->orig_r0;
+ regs->ret -= is_isa_arcv2() ? 2 : 4;
+ break;
+ }
+}
+
+/*
+ * OK, we're invoking a handler
+ */
+static void
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+ sigset_t *oldset = sigmask_to_save();
+ int failed;
+
+ /* Set up the stack frame */
+ failed = setup_rt_frame(ksig, oldset, regs);
+
+ signal_setup_done(failed, ksig, 0);
+}
+
+void do_signal(struct pt_regs *regs)
+{
+ struct ksignal ksig;
+ int restart_scall;
+
+ restart_scall = in_syscall(regs) && syscall_restartable(regs);
+
+ if (test_thread_flag(TIF_SIGPENDING) && get_signal(&ksig)) {
+ if (restart_scall) {
+ arc_restart_syscall(&ksig.ka, regs);
+ syscall_wont_restart(regs); /* No more restarts */
+ }
+ handle_signal(&ksig, regs);
+ return;
+ }
+
+ if (restart_scall) {
+ /* No handler for syscall: restart it */
+ if (regs->r0 == -ERESTARTNOHAND ||
+ regs->r0 == -ERESTARTSYS || regs->r0 == -ERESTARTNOINTR) {
+ regs->r0 = regs->orig_r0;
+ regs->ret -= is_isa_arcv2() ? 2 : 4;
+ } else if (regs->r0 == -ERESTART_RESTARTBLOCK) {
+ regs->r8 = __NR_restart_syscall;
+ regs->ret -= is_isa_arcv2() ? 2 : 4;
+ }
+ syscall_wont_restart(regs); /* No more restarts */
+ }
+
+ /* If there's no signal to deliver, restore the saved sigmask back */
+ restore_saved_sigmask();
+}
+
+void do_notify_resume(struct pt_regs *regs)
+{
+ /*
+ * ASM glue guarantees that this is only called when returning to
+ * user mode
+ */
+ if (test_thread_flag(TIF_NOTIFY_RESUME))
+ resume_user_mode_work(regs);
+}
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
new file mode 100644
index 0000000000..8d9b188caa
--- /dev/null
+++ b/arch/arc/kernel/smp.c
@@ -0,0 +1,414 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * RajeshwarR: Dec 11, 2007
+ * -- Added support for Inter Processor Interrupts
+ *
+ * Vineetg: Nov 1st, 2007
+ * -- Initial Write (Borrowed heavily from ARM)
+ */
+
+#include <linux/spinlock.h>
+#include <linux/sched/mm.h>
+#include <linux/interrupt.h>
+#include <linux/profile.h>
+#include <linux/mm.h>
+#include <linux/cpu.h>
+#include <linux/irq.h>
+#include <linux/atomic.h>
+#include <linux/cpumask.h>
+#include <linux/reboot.h>
+#include <linux/irqdomain.h>
+#include <linux/export.h>
+#include <linux/of_fdt.h>
+
+#include <asm/mach_desc.h>
+#include <asm/setup.h>
+#include <asm/smp.h>
+#include <asm/processor.h>
+
+#ifndef CONFIG_ARC_HAS_LLSC
+arch_spinlock_t smp_atomic_ops_lock = __ARCH_SPIN_LOCK_UNLOCKED;
+
+EXPORT_SYMBOL_GPL(smp_atomic_ops_lock);
+#endif
+
+struct plat_smp_ops __weak plat_smp_ops;
+
+/* XXX: per cpu ? Only needed once in early secondary boot */
+struct task_struct *secondary_idle_tsk;
+
+/* Called from start_kernel */
+void __init smp_prepare_boot_cpu(void)
+{
+}
+
+static int __init arc_get_cpu_map(const char *name, struct cpumask *cpumask)
+{
+ unsigned long dt_root = of_get_flat_dt_root();
+ const char *buf;
+
+ buf = of_get_flat_dt_prop(dt_root, name, NULL);
+ if (!buf)
+ return -EINVAL;
+
+ if (cpulist_parse(buf, cpumask))
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * Read from DeviceTree and setup cpu possible mask. If there is no
+ * "possible-cpus" property in DeviceTree pretend all [0..NR_CPUS-1] exist.
+ */
+static void __init arc_init_cpu_possible(void)
+{
+ struct cpumask cpumask;
+
+ if (arc_get_cpu_map("possible-cpus", &cpumask)) {
+ pr_warn("Failed to get possible-cpus from dtb, pretending all %u cpus exist\n",
+ NR_CPUS);
+
+ cpumask_setall(&cpumask);
+ }
+
+ if (!cpumask_test_cpu(0, &cpumask))
+ panic("Master cpu (cpu[0]) is missed in cpu possible mask!");
+
+ init_cpu_possible(&cpumask);
+}
+
+/*
+ * Called from setup_arch() before calling setup_processor()
+ *
+ * - Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ * - Call early smp init hook. This can initialize a specific multi-core
+ * IP which is say common to several platforms (hence not part of
+ * platform specific int_early() hook)
+ */
+void __init smp_init_cpus(void)
+{
+ arc_init_cpu_possible();
+
+ if (plat_smp_ops.init_early_smp)
+ plat_smp_ops.init_early_smp();
+}
+
+/* called from init ( ) => process 1 */
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ /*
+ * if platform didn't set the present map already, do it now
+ * boot cpu is set to present already by init/main.c
+ */
+ if (num_present_cpus() <= 1)
+ init_cpu_present(cpu_possible_mask);
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+
+}
+
+/*
+ * Default smp boot helper for Run-on-reset case where all cores start off
+ * together. Non-masters need to wait for Master to start running.
+ * This is implemented using a flag in memory, which Non-masters spin-wait on.
+ * Master sets it to cpu-id of core to "ungate" it.
+ */
+static volatile int wake_flag;
+
+#ifdef CONFIG_ISA_ARCOMPACT
+
+#define __boot_read(f) f
+#define __boot_write(f, v) f = v
+
+#else
+
+#define __boot_read(f) arc_read_uncached_32(&f)
+#define __boot_write(f, v) arc_write_uncached_32(&f, v)
+
+#endif
+
+static void arc_default_smp_cpu_kick(int cpu, unsigned long pc)
+{
+ BUG_ON(cpu == 0);
+
+ __boot_write(wake_flag, cpu);
+}
+
+void arc_platform_smp_wait_to_boot(int cpu)
+{
+ /* for halt-on-reset, we've waited already */
+ if (IS_ENABLED(CONFIG_ARC_SMP_HALT_ON_RESET))
+ return;
+
+ while (__boot_read(wake_flag) != cpu)
+ ;
+
+ __boot_write(wake_flag, 0);
+}
+
+const char *arc_platform_smp_cpuinfo(void)
+{
+ return plat_smp_ops.info ? : "";
+}
+
+/*
+ * The very first "C" code executed by secondary
+ * Called from asm stub in head.S
+ * "current"/R25 already setup by low level boot code
+ */
+void start_kernel_secondary(void)
+{
+ struct mm_struct *mm = &init_mm;
+ unsigned int cpu = smp_processor_id();
+
+ /* MMU, Caches, Vector Table, Interrupts etc */
+ setup_processor();
+
+ mmget(mm);
+ mmgrab(mm);
+ current->active_mm = mm;
+ cpumask_set_cpu(cpu, mm_cpumask(mm));
+
+ /* Some SMP H/w setup - for each cpu */
+ if (plat_smp_ops.init_per_cpu)
+ plat_smp_ops.init_per_cpu(cpu);
+
+ if (machine_desc->init_per_cpu)
+ machine_desc->init_per_cpu(cpu);
+
+ notify_cpu_starting(cpu);
+ set_cpu_online(cpu, true);
+
+ pr_info("## CPU%u LIVE ##: Executing Code...\n", cpu);
+
+ local_irq_enable();
+ cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
+}
+
+/*
+ * Called from kernel_init( ) -> smp_init( ) - for each CPU
+ *
+ * At this point, Secondary Processor is "HALT"ed:
+ * -It booted, but was halted in head.S
+ * -It was configured to halt-on-reset
+ * So need to wake it up.
+ *
+ * Essential requirements being where to run from (PC) and stack (SP)
+*/
+int __cpu_up(unsigned int cpu, struct task_struct *idle)
+{
+ unsigned long wait_till;
+
+ secondary_idle_tsk = idle;
+
+ pr_info("Idle Task [%d] %p", cpu, idle);
+ pr_info("Trying to bring up CPU%u ...\n", cpu);
+
+ if (plat_smp_ops.cpu_kick)
+ plat_smp_ops.cpu_kick(cpu,
+ (unsigned long)first_lines_of_secondary);
+ else
+ arc_default_smp_cpu_kick(cpu, (unsigned long)NULL);
+
+ /* wait for 1 sec after kicking the secondary */
+ wait_till = jiffies + HZ;
+ while (time_before(jiffies, wait_till)) {
+ if (cpu_online(cpu))
+ break;
+ }
+
+ if (!cpu_online(cpu)) {
+ pr_info("Timeout: CPU%u FAILED to come up !!!\n", cpu);
+ return -1;
+ }
+
+ secondary_idle_tsk = NULL;
+
+ return 0;
+}
+
+/*****************************************************************************/
+/* Inter Processor Interrupt Handling */
+/*****************************************************************************/
+
+enum ipi_msg_type {
+ IPI_EMPTY = 0,
+ IPI_RESCHEDULE = 1,
+ IPI_CALL_FUNC,
+ IPI_CPU_STOP,
+};
+
+/*
+ * In arches with IRQ for each msg type (above), receiver can use IRQ-id to
+ * figure out what msg was sent. For those which don't (ARC has dedicated IPI
+ * IRQ), the msg-type needs to be conveyed via per-cpu data
+ */
+
+static DEFINE_PER_CPU(unsigned long, ipi_data);
+
+static void ipi_send_msg_one(int cpu, enum ipi_msg_type msg)
+{
+ unsigned long __percpu *ipi_data_ptr = per_cpu_ptr(&ipi_data, cpu);
+ unsigned long old, new;
+ unsigned long flags;
+
+ pr_debug("%d Sending msg [%d] to %d\n", smp_processor_id(), msg, cpu);
+
+ local_irq_save(flags);
+
+ /*
+ * Atomically write new msg bit (in case others are writing too),
+ * and read back old value
+ */
+ do {
+ new = old = *ipi_data_ptr;
+ new |= 1U << msg;
+ } while (cmpxchg(ipi_data_ptr, old, new) != old);
+
+ /*
+ * Call the platform specific IPI kick function, but avoid if possible:
+ * Only do so if there's no pending msg from other concurrent sender(s).
+ * Otherwise, receiver will see this msg as well when it takes the
+ * IPI corresponding to that msg. This is true, even if it is already in
+ * IPI handler, because !@old means it has not yet dequeued the msg(s)
+ * so @new msg can be a free-loader
+ */
+ if (plat_smp_ops.ipi_send && !old)
+ plat_smp_ops.ipi_send(cpu);
+
+ local_irq_restore(flags);
+}
+
+static void ipi_send_msg(const struct cpumask *callmap, enum ipi_msg_type msg)
+{
+ unsigned int cpu;
+
+ for_each_cpu(cpu, callmap)
+ ipi_send_msg_one(cpu, msg);
+}
+
+void arch_smp_send_reschedule(int cpu)
+{
+ ipi_send_msg_one(cpu, IPI_RESCHEDULE);
+}
+
+void smp_send_stop(void)
+{
+ struct cpumask targets;
+ cpumask_copy(&targets, cpu_online_mask);
+ cpumask_clear_cpu(smp_processor_id(), &targets);
+ ipi_send_msg(&targets, IPI_CPU_STOP);
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ ipi_send_msg_one(cpu, IPI_CALL_FUNC);
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+ ipi_send_msg(mask, IPI_CALL_FUNC);
+}
+
+/*
+ * ipi_cpu_stop - handle IPI from smp_send_stop()
+ */
+static void ipi_cpu_stop(void)
+{
+ machine_halt();
+}
+
+static inline int __do_IPI(unsigned long msg)
+{
+ int rc = 0;
+
+ switch (msg) {
+ case IPI_RESCHEDULE:
+ scheduler_ipi();
+ break;
+
+ case IPI_CALL_FUNC:
+ generic_smp_call_function_interrupt();
+ break;
+
+ case IPI_CPU_STOP:
+ ipi_cpu_stop();
+ break;
+
+ default:
+ rc = 1;
+ }
+
+ return rc;
+}
+
+/*
+ * arch-common ISR to handle for inter-processor interrupts
+ * Has hooks for platform specific IPI
+ */
+static irqreturn_t do_IPI(int irq, void *dev_id)
+{
+ unsigned long pending;
+ unsigned long __maybe_unused copy;
+
+ pr_debug("IPI [%ld] received on cpu %d\n",
+ *this_cpu_ptr(&ipi_data), smp_processor_id());
+
+ if (plat_smp_ops.ipi_clear)
+ plat_smp_ops.ipi_clear(irq);
+
+ /*
+ * "dequeue" the msg corresponding to this IPI (and possibly other
+ * piggybacked msg from elided IPIs: see ipi_send_msg_one() above)
+ */
+ copy = pending = xchg(this_cpu_ptr(&ipi_data), 0);
+
+ do {
+ unsigned long msg = __ffs(pending);
+ int rc;
+
+ rc = __do_IPI(msg);
+ if (rc)
+ pr_info("IPI with bogus msg %ld in %ld\n", msg, copy);
+ pending &= ~(1U << msg);
+ } while (pending);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * API called by platform code to hookup arch-common ISR to their IPI IRQ
+ *
+ * Note: If IPI is provided by platform (vs. say ARC MCIP), their intc setup/map
+ * function needs to call irq_set_percpu_devid() for IPI IRQ, otherwise
+ * request_percpu_irq() below will fail
+ */
+static DEFINE_PER_CPU(int, ipi_dev);
+
+int smp_ipi_irq_setup(int cpu, irq_hw_number_t hwirq)
+{
+ int *dev = per_cpu_ptr(&ipi_dev, cpu);
+ unsigned int virq = irq_find_mapping(NULL, hwirq);
+
+ if (!virq)
+ panic("Cannot find virq for root domain and hwirq=%lu", hwirq);
+
+ /* Boot cpu calls request, all call enable */
+ if (!cpu) {
+ int rc;
+
+ rc = request_percpu_irq(virq, do_IPI, "IPI Interrupt", dev);
+ if (rc)
+ panic("Percpu IRQ request failed for %u\n", virq);
+ }
+
+ enable_percpu_irq(virq, 0);
+
+ return 0;
+}
diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c
new file mode 100644
index 0000000000..ea99c066ef
--- /dev/null
+++ b/arch/arc/kernel/stacktrace.c
@@ -0,0 +1,275 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * stacktrace.c : stacktracing APIs needed by rest of kernel
+ * (wrappers over ARC dwarf based unwinder)
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * vineetg: aug 2009
+ * -Implemented CONFIG_STACKTRACE APIs, primarily save_stack_trace_tsk( )
+ * for displaying task's kernel mode call stack in /proc/<pid>/stack
+ * -Iterator based approach to have single copy of unwinding core and APIs
+ * needing unwinding, implement the logic in iterator regarding:
+ * = which frame onwards to start capture
+ * = which frame to stop capturing (wchan)
+ * = specifics of data structs where trace is saved(CONFIG_STACKTRACE etc)
+ *
+ * vineetg: March 2009
+ * -Implemented correct versions of thread_saved_pc() and __get_wchan()
+ *
+ * rajeshwarr: 2008
+ * -Initial implementation
+ */
+
+#include <linux/ptrace.h>
+#include <linux/export.h>
+#include <linux/stacktrace.h>
+#include <linux/kallsyms.h>
+#include <linux/sched/debug.h>
+
+#include <asm/arcregs.h>
+#include <asm/unwind.h>
+#include <asm/stacktrace.h>
+#include <asm/switch_to.h>
+
+/*-------------------------------------------------------------------------
+ * Unwinder Iterator
+ *-------------------------------------------------------------------------
+ */
+
+#ifdef CONFIG_ARC_DW2_UNWIND
+
+static int
+seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs,
+ struct unwind_frame_info *frame_info)
+{
+ if (regs) {
+ /*
+ * Asynchronous unwinding of intr/exception
+ * - Just uses the pt_regs passed
+ */
+ frame_info->task = tsk;
+
+ frame_info->regs.r27 = regs->fp;
+ frame_info->regs.r28 = regs->sp;
+ frame_info->regs.r31 = regs->blink;
+ frame_info->regs.r63 = regs->ret;
+ frame_info->call_frame = 0;
+ } else if (tsk == NULL || tsk == current) {
+ /*
+ * synchronous unwinding (e.g. dump_stack)
+ * - uses current values of SP and friends
+ */
+ unsigned long fp, sp, blink, ret;
+ frame_info->task = current;
+
+ __asm__ __volatile__(
+ "mov %0,r27\n\t"
+ "mov %1,r28\n\t"
+ "mov %2,r31\n\t"
+ "mov %3,r63\n\t"
+ : "=r"(fp), "=r"(sp), "=r"(blink), "=r"(ret)
+ );
+
+ frame_info->regs.r27 = fp;
+ frame_info->regs.r28 = sp;
+ frame_info->regs.r31 = blink;
+ frame_info->regs.r63 = ret;
+ frame_info->call_frame = 0;
+ } else {
+ /*
+ * Asynchronous unwinding of a likely sleeping task
+ * - first ensure it is actually sleeping
+ * - if so, it will be in __switch_to, kernel mode SP of task
+ * is safe-kept and BLINK at a well known location in there
+ */
+
+ if (task_is_running(tsk))
+ return -1;
+
+ frame_info->task = tsk;
+
+ frame_info->regs.r27 = TSK_K_FP(tsk);
+ frame_info->regs.r28 = TSK_K_ESP(tsk);
+ frame_info->regs.r31 = TSK_K_BLINK(tsk);
+ frame_info->regs.r63 = (unsigned int)__switch_to;
+
+ /* In the prologue of __switch_to, first FP is saved on stack
+ * and then SP is copied to FP. Dwarf assumes cfa as FP based
+ * but we didn't save FP. The value retrieved above is FP's
+ * state in previous frame.
+ * As a work around for this, we unwind from __switch_to start
+ * and adjust SP accordingly. The other limitation is that
+ * __switch_to macro is dwarf rules are not generated for inline
+ * assembly code
+ */
+ frame_info->regs.r27 = 0;
+ frame_info->regs.r28 += 60;
+ frame_info->call_frame = 0;
+
+ }
+ return 0;
+}
+
+#endif
+
+notrace noinline unsigned int
+arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs,
+ int (*consumer_fn) (unsigned int, void *), void *arg)
+{
+#ifdef CONFIG_ARC_DW2_UNWIND
+ int ret = 0, cnt = 0;
+ unsigned int address;
+ struct unwind_frame_info frame_info;
+
+ if (seed_unwind_frame_info(tsk, regs, &frame_info))
+ return 0;
+
+ while (1) {
+ address = UNW_PC(&frame_info);
+
+ if (!address || !__kernel_text_address(address))
+ break;
+
+ if (consumer_fn(address, arg) == -1)
+ break;
+
+ ret = arc_unwind(&frame_info);
+ if (ret)
+ break;
+
+ frame_info.regs.r63 = frame_info.regs.r31;
+
+ if (cnt++ > 128) {
+ printk("unwinder looping too long, aborting !\n");
+ return 0;
+ }
+ }
+
+ return address; /* return the last address it saw */
+#else
+ /* On ARC, only Dward based unwinder works. fp based backtracing is
+ * not possible (-fno-omit-frame-pointer) because of the way function
+ * prologue is setup (callee regs saved and then fp set and not other
+ * way around
+ */
+ pr_warn_once("CONFIG_ARC_DW2_UNWIND needs to be enabled\n");
+ return 0;
+
+#endif
+}
+
+/*-------------------------------------------------------------------------
+ * callbacks called by unwinder iterator to implement kernel APIs
+ *
+ * The callback can return -1 to force the iterator to stop, which by default
+ * keeps going till the bottom-most frame.
+ *-------------------------------------------------------------------------
+ */
+
+/* Call-back which plugs into unwinding core to dump the stack in
+ * case of panic/OOPs/BUG etc
+ */
+static int __print_sym(unsigned int address, void *arg)
+{
+ const char *loglvl = arg;
+
+ printk("%s %pS\n", loglvl, (void *)address);
+ return 0;
+}
+
+#ifdef CONFIG_STACKTRACE
+
+/* Call-back which plugs into unwinding core to capture the
+ * traces needed by kernel on /proc/<pid>/stack
+ */
+static int __collect_all(unsigned int address, void *arg)
+{
+ struct stack_trace *trace = arg;
+
+ if (trace->skip > 0)
+ trace->skip--;
+ else
+ trace->entries[trace->nr_entries++] = address;
+
+ if (trace->nr_entries >= trace->max_entries)
+ return -1;
+
+ return 0;
+}
+
+static int __collect_all_but_sched(unsigned int address, void *arg)
+{
+ struct stack_trace *trace = arg;
+
+ if (in_sched_functions(address))
+ return 0;
+
+ if (trace->skip > 0)
+ trace->skip--;
+ else
+ trace->entries[trace->nr_entries++] = address;
+
+ if (trace->nr_entries >= trace->max_entries)
+ return -1;
+
+ return 0;
+}
+
+#endif
+
+static int __get_first_nonsched(unsigned int address, void *unused)
+{
+ if (in_sched_functions(address))
+ return 0;
+
+ return -1;
+}
+
+/*-------------------------------------------------------------------------
+ * APIs expected by various kernel sub-systems
+ *-------------------------------------------------------------------------
+ */
+
+noinline void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs,
+ const char *loglvl)
+{
+ printk("%s\nStack Trace:\n", loglvl);
+ arc_unwind_core(tsk, regs, __print_sym, (void *)loglvl);
+}
+EXPORT_SYMBOL(show_stacktrace);
+
+/* Expected by sched Code */
+void show_stack(struct task_struct *tsk, unsigned long *sp, const char *loglvl)
+{
+ show_stacktrace(tsk, NULL, loglvl);
+}
+
+/* Another API expected by schedular, shows up in "ps" as Wait Channel
+ * Of course just returning schedule( ) would be pointless so unwind until
+ * the function is not in schedular code
+ */
+unsigned int __get_wchan(struct task_struct *tsk)
+{
+ return arc_unwind_core(tsk, NULL, __get_first_nonsched, NULL);
+}
+
+#ifdef CONFIG_STACKTRACE
+
+/*
+ * API required by CONFIG_STACKTRACE, CONFIG_LATENCYTOP.
+ * A typical use is when /proc/<pid>/stack is queried by userland
+ */
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+ /* Assumes @tsk is sleeping so unwinds from __switch_to */
+ arc_unwind_core(tsk, NULL, __collect_all_but_sched, trace);
+}
+
+void save_stack_trace(struct stack_trace *trace)
+{
+ /* Pass NULL for task so it unwinds the current call frame */
+ arc_unwind_core(NULL, NULL, __collect_all, trace);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace);
+#endif
diff --git a/arch/arc/kernel/sys.c b/arch/arc/kernel/sys.c
new file mode 100644
index 0000000000..1069446bdc
--- /dev/null
+++ b/arch/arc/kernel/sys.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/syscalls.h>
+#include <linux/signal.h>
+#include <linux/unistd.h>
+
+#include <asm/syscalls.h>
+
+#define sys_clone sys_clone_wrapper
+#define sys_clone3 sys_clone3_wrapper
+
+#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/arc/kernel/traps.c b/arch/arc/kernel/traps.c
new file mode 100644
index 0000000000..9b9570b793
--- /dev/null
+++ b/arch/arc/kernel/traps.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Traps/Non-MMU Exception handling for ARC
+ *
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * vineetg: May 2011
+ * -user-space unaligned access emulation
+ *
+ * Rahul Trivedi: Codito Technologies 2004
+ */
+
+#include <linux/sched/signal.h>
+#include <linux/kdebug.h>
+#include <linux/uaccess.h>
+#include <linux/ptrace.h>
+#include <linux/kprobes.h>
+#include <linux/kgdb.h>
+#include <asm/entry.h>
+#include <asm/setup.h>
+#include <asm/unaligned.h>
+#include <asm/kprobes.h>
+
+void die(const char *str, struct pt_regs *regs, unsigned long address)
+{
+ show_kernel_fault_diag(str, regs, address);
+
+ /* DEAD END */
+ __asm__("flag 1");
+}
+
+/*
+ * Helper called for bulk of exceptions NOT needing specific handling
+ * -for user faults enqueues requested signal
+ * -for kernel, chk if due to copy_(to|from)_user, otherwise die()
+ */
+static noinline int
+unhandled_exception(const char *str, struct pt_regs *regs,
+ int signo, int si_code, void __user *addr)
+{
+ if (user_mode(regs)) {
+ struct task_struct *tsk = current;
+
+ tsk->thread.fault_address = (__force unsigned int)addr;
+
+ force_sig_fault(signo, si_code, addr);
+
+ } else {
+ /* If not due to copy_(to|from)_user, we are doomed */
+ if (fixup_exception(regs))
+ return 0;
+
+ die(str, regs, (unsigned long)addr);
+ }
+
+ return 1;
+}
+
+#define DO_ERROR_INFO(signr, str, name, sicode) \
+int name(unsigned long address, struct pt_regs *regs) \
+{ \
+ return unhandled_exception(str, regs, signr, sicode, \
+ (void __user *)address); \
+}
+
+/*
+ * Entry points for exceptions NOT needing specific handling
+ */
+DO_ERROR_INFO(SIGILL, "Priv Op/Disabled Extn", do_privilege_fault, ILL_PRVOPC)
+DO_ERROR_INFO(SIGILL, "Invalid Extn Insn", do_extension_fault, ILL_ILLOPC)
+DO_ERROR_INFO(SIGILL, "Illegal Insn (or Seq)", insterror_is_error, ILL_ILLOPC)
+DO_ERROR_INFO(SIGBUS, "Invalid Mem Access", __weak do_memory_error, BUS_ADRERR)
+DO_ERROR_INFO(SIGTRAP, "Breakpoint Set", trap_is_brkpt, TRAP_BRKPT)
+DO_ERROR_INFO(SIGBUS, "Misaligned Access", do_misaligned_error, BUS_ADRALN)
+DO_ERROR_INFO(SIGSEGV, "gcc generated __builtin_trap", do_trap5_error, 0)
+
+/*
+ * Entry Point for Misaligned Data access Exception, for emulating in software
+ */
+int do_misaligned_access(unsigned long address, struct pt_regs *regs,
+ struct callee_regs *cregs)
+{
+ /* If emulation not enabled, or failed, kill the task */
+ if (misaligned_fixup(address, regs, cregs) != 0)
+ return do_misaligned_error(address, regs);
+
+ return 0;
+}
+
+/*
+ * Entry point for miscll errors such as Nested Exceptions
+ * -Duplicate TLB entry is handled seperately though
+ */
+void do_machine_check_fault(unsigned long address, struct pt_regs *regs)
+{
+ die("Unhandled Machine Check Exception", regs, address);
+}
+
+
+/*
+ * Entry point for traps induced by ARCompact TRAP_S <n> insn
+ * This is same family as TRAP0/SWI insn (use the same vector).
+ * The only difference being SWI insn take no operand, while TRAP_S does
+ * which reflects in ECR Reg as 8 bit param.
+ * Thus TRAP_S <n> can be used for specific purpose
+ * -1 used for software breakpointing (gdb)
+ * -2 used by kprobes
+ * -5 __builtin_trap() generated by gcc (2018.03 onwards) for toggle such as
+ * -fno-isolate-erroneous-paths-dereference
+ */
+void do_non_swi_trap(unsigned long address, struct pt_regs *regs)
+{
+ switch (regs->ecr.param) {
+ case 1:
+ trap_is_brkpt(address, regs);
+ break;
+
+ case 2:
+ trap_is_kprobe(address, regs);
+ break;
+
+ case 3:
+ case 4:
+ kgdb_trap(regs);
+ break;
+
+ case 5:
+ do_trap5_error(address, regs);
+ break;
+ default:
+ break;
+ }
+}
+
+/*
+ * Entry point for Instruction Error Exception
+ * -For a corner case, ARC kprobes implementation resorts to using
+ * this exception, hence the check
+ */
+void do_insterror_or_kprobe(unsigned long address, struct pt_regs *regs)
+{
+ int rc;
+
+ /* Check if this exception is caused by kprobes */
+ rc = notify_die(DIE_IERR, "kprobe_ierr", regs, address, 0, SIGILL);
+ if (rc == NOTIFY_STOP)
+ return;
+
+ insterror_is_error(address, regs);
+}
+
+/*
+ * abort() call generated by older gcc for __builtin_trap()
+ */
+void abort(void)
+{
+ __asm__ __volatile__("trap_s 5\n");
+}
diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c
new file mode 100644
index 0000000000..d5b3ed2c58
--- /dev/null
+++ b/arch/arc/kernel/troubleshoot.c
@@ -0,0 +1,228 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/ptrace.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/kdev_t.h>
+#include <linux/proc_fs.h>
+#include <linux/file.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/debug.h>
+
+#include <asm/arcregs.h>
+#include <asm/irqflags.h>
+
+#define ARC_PATH_MAX 256
+
+static noinline void print_regs_scratch(struct pt_regs *regs)
+{
+ pr_cont("BTA: 0x%08lx\n SP: 0x%08lx FP: 0x%08lx BLK: %pS\n",
+ regs->bta, regs->sp, regs->fp, (void *)regs->blink);
+ pr_cont("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
+ regs->lp_start, regs->lp_end, regs->lp_count);
+
+ pr_info("r00: 0x%08lx\tr01: 0x%08lx\tr02: 0x%08lx\n" \
+ "r03: 0x%08lx\tr04: 0x%08lx\tr05: 0x%08lx\n" \
+ "r06: 0x%08lx\tr07: 0x%08lx\tr08: 0x%08lx\n" \
+ "r09: 0x%08lx\tr10: 0x%08lx\tr11: 0x%08lx\n" \
+ "r12: 0x%08lx\t",
+ regs->r0, regs->r1, regs->r2,
+ regs->r3, regs->r4, regs->r5,
+ regs->r6, regs->r7, regs->r8,
+ regs->r9, regs->r10, regs->r11,
+ regs->r12);
+}
+
+static void print_regs_callee(struct callee_regs *regs)
+{
+ pr_cont("r13: 0x%08lx\tr14: 0x%08lx\n" \
+ "r15: 0x%08lx\tr16: 0x%08lx\tr17: 0x%08lx\n" \
+ "r18: 0x%08lx\tr19: 0x%08lx\tr20: 0x%08lx\n" \
+ "r21: 0x%08lx\tr22: 0x%08lx\tr23: 0x%08lx\n" \
+ "r24: 0x%08lx\tr25: 0x%08lx\n",
+ regs->r13, regs->r14,
+ regs->r15, regs->r16, regs->r17,
+ regs->r18, regs->r19, regs->r20,
+ regs->r21, regs->r22, regs->r23,
+ regs->r24, regs->r25);
+}
+
+static void print_task_path_n_nm(struct task_struct *tsk)
+{
+ char *path_nm = NULL;
+ struct mm_struct *mm;
+ struct file *exe_file;
+ char buf[ARC_PATH_MAX];
+
+ mm = get_task_mm(tsk);
+ if (!mm)
+ goto done;
+
+ exe_file = get_mm_exe_file(mm);
+ mmput(mm);
+
+ if (exe_file) {
+ path_nm = file_path(exe_file, buf, ARC_PATH_MAX-1);
+ fput(exe_file);
+ }
+
+done:
+ pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?");
+}
+
+static void show_faulting_vma(unsigned long address)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *active_mm = current->active_mm;
+
+ /* can't use print_vma_addr() yet as it doesn't check for
+ * non-inclusive vma
+ */
+ mmap_read_lock(active_mm);
+ vma = vma_lookup(active_mm, address);
+
+ /* Lookup the vma at the address and report if the container VMA is not
+ * found
+ */
+ if (vma) {
+ char buf[ARC_PATH_MAX];
+ char *nm = "?";
+
+ if (vma->vm_file) {
+ nm = file_path(vma->vm_file, buf, ARC_PATH_MAX-1);
+ if (IS_ERR(nm))
+ nm = "?";
+ }
+ pr_info(" @off 0x%lx in [%s] VMA: 0x%08lx to 0x%08lx\n",
+ vma->vm_start < TASK_UNMAPPED_BASE ?
+ address : address - vma->vm_start,
+ nm, vma->vm_start, vma->vm_end);
+ } else
+ pr_info(" @No matching VMA found\n");
+
+ mmap_read_unlock(active_mm);
+}
+
+static void show_ecr_verbose(struct pt_regs *regs)
+{
+ unsigned int vec, cause_code;
+ unsigned long address;
+
+ /* For Data fault, this is data address not instruction addr */
+ address = current->thread.fault_address;
+
+ vec = regs->ecr.vec;
+ cause_code = regs->ecr.cause;
+
+ /* For DTLB Miss or ProtV, display the memory involved too */
+ if (vec == ECR_V_DTLB_MISS) {
+ pr_cont("Invalid %s @ 0x%08lx by insn @ %pS\n",
+ (cause_code == 0x01) ? "Read" :
+ ((cause_code == 0x02) ? "Write" : "EX"),
+ address, (void *)regs->ret);
+ } else if (vec == ECR_V_ITLB_MISS) {
+ pr_cont("Insn could not be fetched\n");
+ } else if (vec == ECR_V_MACH_CHK) {
+ pr_cont("Machine Check (%s)\n", (cause_code == 0x0) ?
+ "Double Fault" : "Other Fatal Err");
+
+ } else if (vec == ECR_V_PROTV) {
+ if (cause_code == ECR_C_PROTV_INST_FETCH)
+ pr_cont("Execute from Non-exec Page\n");
+ else if (cause_code == ECR_C_PROTV_MISALIG_DATA &&
+ IS_ENABLED(CONFIG_ISA_ARCOMPACT))
+ pr_cont("Misaligned r/w from 0x%08lx\n", address);
+ else
+ pr_cont("%s access not allowed on page\n",
+ (cause_code == 0x01) ? "Read" :
+ ((cause_code == 0x02) ? "Write" : "EX"));
+ } else if (vec == ECR_V_INSN_ERR) {
+ pr_cont("Illegal Insn\n");
+#ifdef CONFIG_ISA_ARCV2
+ } else if (vec == ECR_V_MEM_ERR) {
+ if (cause_code == 0x00)
+ pr_cont("Bus Error from Insn Mem\n");
+ else if (cause_code == 0x10)
+ pr_cont("Bus Error from Data Mem\n");
+ else
+ pr_cont("Bus Error, check PRM\n");
+ } else if (vec == ECR_V_MISALIGN) {
+ pr_cont("Misaligned r/w from 0x%08lx\n", address);
+#endif
+ } else if (vec == ECR_V_TRAP) {
+ if (regs->ecr.param == 5)
+ pr_cont("gcc generated __builtin_trap\n");
+ } else {
+ pr_cont("Check Programmer's Manual\n");
+ }
+}
+
+/************************************************************************
+ * API called by rest of kernel
+ ***********************************************************************/
+
+void show_regs(struct pt_regs *regs)
+{
+ struct task_struct *tsk = current;
+ struct callee_regs *cregs = (struct callee_regs *)tsk->thread.callee_reg;
+
+ /*
+ * generic code calls us with preemption disabled, but some calls
+ * here could sleep, so re-enable to avoid lockdep splat
+ */
+ preempt_enable();
+
+ print_task_path_n_nm(tsk);
+ show_regs_print_info(KERN_INFO);
+
+ show_ecr_verbose(regs);
+
+ if (user_mode(regs))
+ show_faulting_vma(regs->ret); /* faulting code, not data */
+
+ pr_info("ECR: 0x%08lx EFA: 0x%08lx ERET: 0x%08lx\n",
+ regs->ecr.full, current->thread.fault_address, regs->ret);
+
+ pr_info("STAT32: 0x%08lx", regs->status32);
+
+#define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit" " : ""
+
+#ifdef CONFIG_ISA_ARCOMPACT
+ pr_cont(" [%2s%2s%2s%2s%2s%2s%2s]",
+ (regs->status32 & STATUS_U_MASK) ? "U " : "K ",
+ STS_BIT(regs, DE), STS_BIT(regs, AE),
+ STS_BIT(regs, A2), STS_BIT(regs, A1),
+ STS_BIT(regs, E2), STS_BIT(regs, E1));
+#else
+ pr_cont(" [%2s%2s%2s%2s] ",
+ STS_BIT(regs, IE),
+ (regs->status32 & STATUS_U_MASK) ? "U " : "K ",
+ STS_BIT(regs, DE), STS_BIT(regs, AE));
+#endif
+
+ print_regs_scratch(regs);
+ if (cregs)
+ print_regs_callee(cregs);
+
+ preempt_disable();
+}
+
+void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
+ unsigned long address)
+{
+ current->thread.fault_address = address;
+
+ /* Show fault description */
+ pr_info("\n%s\n", str);
+
+ /* Caller and Callee regs */
+ show_regs(regs);
+
+ /* Show stack trace if this Fatality happened in kernel mode */
+ if (!user_mode(regs))
+ show_stacktrace(current, regs, KERN_DEFAULT);
+}
diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c
new file mode 100644
index 0000000000..99a9b92ed9
--- /dev/null
+++ b/arch/arc/kernel/unaligned.c
@@ -0,0 +1,262 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011-2012 Synopsys (www.synopsys.com)
+ *
+ * vineetg : May 2011
+ * -Adapted (from .26 to .35)
+ * -original contribution by Tim.yao@amlogic.com
+ */
+
+#include <linux/types.h>
+#include <linux/perf_event.h>
+#include <linux/ptrace.h>
+#include <linux/uaccess.h>
+#include <asm/disasm.h>
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+#define BE 1
+#define FIRST_BYTE_16 "swap %1, %1\n swape %1, %1\n"
+#define FIRST_BYTE_32 "swape %1, %1\n"
+#else
+#define BE 0
+#define FIRST_BYTE_16
+#define FIRST_BYTE_32
+#endif
+
+#define __get8_unaligned_check(val, addr, err) \
+ __asm__( \
+ "1: ldb.ab %1, [%2, 1]\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 4\n" \
+ "3: mov %0, 1\n" \
+ " j 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 1b, 3b\n" \
+ " .previous\n" \
+ : "=r" (err), "=&r" (val), "=r" (addr) \
+ : "0" (err), "2" (addr))
+
+#define get16_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v, a = addr; \
+ __get8_unaligned_check(v, a, err); \
+ val = v << ((BE) ? 8 : 0); \
+ __get8_unaligned_check(v, a, err); \
+ val |= v << ((BE) ? 0 : 8); \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define get32_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v, a = addr; \
+ __get8_unaligned_check(v, a, err); \
+ val = v << ((BE) ? 24 : 0); \
+ __get8_unaligned_check(v, a, err); \
+ val |= v << ((BE) ? 16 : 8); \
+ __get8_unaligned_check(v, a, err); \
+ val |= v << ((BE) ? 8 : 16); \
+ __get8_unaligned_check(v, a, err); \
+ val |= v << ((BE) ? 0 : 24); \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define put16_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v = val, a = addr;\
+ \
+ __asm__( \
+ FIRST_BYTE_16 \
+ "1: stb.ab %1, [%2, 1]\n" \
+ " lsr %1, %1, 8\n" \
+ "2: stb %1, [%2]\n" \
+ "3:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 4\n" \
+ "4: mov %0, 1\n" \
+ " j 3b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 1b, 4b\n" \
+ " .long 2b, 4b\n" \
+ " .previous\n" \
+ : "=r" (err), "=&r" (v), "=&r" (a) \
+ : "0" (err), "1" (v), "2" (a)); \
+ \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+#define put32_unaligned_check(val, addr) \
+ do { \
+ unsigned int err = 0, v = val, a = addr;\
+ \
+ __asm__( \
+ FIRST_BYTE_32 \
+ "1: stb.ab %1, [%2, 1]\n" \
+ " lsr %1, %1, 8\n" \
+ "2: stb.ab %1, [%2, 1]\n" \
+ " lsr %1, %1, 8\n" \
+ "3: stb.ab %1, [%2, 1]\n" \
+ " lsr %1, %1, 8\n" \
+ "4: stb %1, [%2]\n" \
+ "5:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 4\n" \
+ "6: mov %0, 1\n" \
+ " j 5b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 4\n" \
+ " .long 1b, 6b\n" \
+ " .long 2b, 6b\n" \
+ " .long 3b, 6b\n" \
+ " .long 4b, 6b\n" \
+ " .previous\n" \
+ : "=r" (err), "=&r" (v), "=&r" (a) \
+ : "0" (err), "1" (v), "2" (a)); \
+ \
+ if (err) \
+ goto fault; \
+ } while (0)
+
+/* sysctl hooks */
+int unaligned_enabled __read_mostly = 1; /* Enabled by default */
+int no_unaligned_warning __read_mostly = 1; /* Only 1 warning by default */
+
+static void fixup_load(struct disasm_state *state, struct pt_regs *regs,
+ struct callee_regs *cregs)
+{
+ int val;
+
+ /* register write back */
+ if ((state->aa == 1) || (state->aa == 2)) {
+ set_reg(state->wb_reg, state->src1 + state->src2, regs, cregs);
+
+ if (state->aa == 2)
+ state->src2 = 0;
+ }
+
+ if (state->zz == 0) {
+ get32_unaligned_check(val, state->src1 + state->src2);
+ } else {
+ get16_unaligned_check(val, state->src1 + state->src2);
+
+ if (state->x)
+ val = (val << 16) >> 16;
+ }
+
+ if (state->pref == 0)
+ set_reg(state->dest, val, regs, cregs);
+
+ return;
+
+fault: state->fault = 1;
+}
+
+static void fixup_store(struct disasm_state *state, struct pt_regs *regs,
+ struct callee_regs *cregs)
+{
+ /* register write back */
+ if ((state->aa == 1) || (state->aa == 2)) {
+ set_reg(state->wb_reg, state->src2 + state->src3, regs, cregs);
+
+ if (state->aa == 3)
+ state->src3 = 0;
+ } else if (state->aa == 3) {
+ if (state->zz == 2) {
+ set_reg(state->wb_reg, state->src2 + (state->src3 << 1),
+ regs, cregs);
+ } else if (!state->zz) {
+ set_reg(state->wb_reg, state->src2 + (state->src3 << 2),
+ regs, cregs);
+ } else {
+ goto fault;
+ }
+ }
+
+ /* write fix-up */
+ if (!state->zz)
+ put32_unaligned_check(state->src1, state->src2 + state->src3);
+ else
+ put16_unaligned_check(state->src1, state->src2 + state->src3);
+
+ return;
+
+fault: state->fault = 1;
+}
+
+/*
+ * Handle an unaligned access
+ * Returns 0 if successfully handled, 1 if some error happened
+ */
+int misaligned_fixup(unsigned long address, struct pt_regs *regs,
+ struct callee_regs *cregs)
+{
+ struct disasm_state state;
+ char buf[TASK_COMM_LEN];
+
+ /* handle user mode only and only if enabled by sysadmin */
+ if (!user_mode(regs) || !unaligned_enabled)
+ return 1;
+
+ if (no_unaligned_warning) {
+ pr_warn_once("%s(%d) made unaligned access which was emulated"
+ " by kernel assist\n. This can degrade application"
+ " performance significantly\n. To enable further"
+ " logging of such instances, please \n"
+ " echo 0 > /proc/sys/kernel/ignore-unaligned-usertrap\n",
+ get_task_comm(buf, current), task_pid_nr(current));
+ } else {
+ /* Add rate limiting if it gets down to it */
+ pr_warn("%s(%d): unaligned access to/from 0x%lx by PC: 0x%lx\n",
+ get_task_comm(buf, current), task_pid_nr(current),
+ address, regs->ret);
+
+ }
+
+ disasm_instr(regs->ret, &state, 1, regs, cregs);
+
+ if (state.fault)
+ goto fault;
+
+ /* ldb/stb should not have unaligned exception */
+ if ((state.zz == 1) || (state.di))
+ goto fault;
+
+ if (!state.write)
+ fixup_load(&state, regs, cregs);
+ else
+ fixup_store(&state, regs, cregs);
+
+ if (state.fault)
+ goto fault;
+
+ /* clear any remnants of delay slot */
+ if (delay_mode(regs)) {
+ regs->ret = regs->bta & ~1U;
+ regs->status32 &= ~STATUS_DE_MASK;
+ } else {
+ regs->ret += state.instr_len;
+
+ /* handle zero-overhead-loop */
+ if ((regs->ret == regs->lp_end) && (regs->lp_count)) {
+ regs->ret = regs->lp_start;
+ regs->lp_count--;
+ }
+ }
+
+ perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address);
+ return 0;
+
+fault:
+ pr_err("Alignment trap: fault in fix-up %08lx at [<%08lx>]\n",
+ state.words[0], address);
+
+ return 1;
+}
diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c
new file mode 100644
index 0000000000..9270d0a713
--- /dev/null
+++ b/arch/arc/kernel/unwind.c
@@ -0,0 +1,1315 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ * Copyright (C) 2002-2006 Novell, Inc.
+ * Jan Beulich <jbeulich@novell.com>
+ *
+ * A simple API for unwinding kernel stacks. This is used for
+ * debugging and error reporting purposes. The kernel doesn't need
+ * full-blown stack unwinding with all the bells and whistles, so there
+ * is not much point in implementing the full Dwarf2 unwind API.
+ */
+
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/memblock.h>
+#include <linux/sort.h>
+#include <linux/slab.h>
+#include <linux/stop_machine.h>
+#include <linux/uaccess.h>
+#include <linux/ptrace.h>
+#include <asm/sections.h>
+#include <asm/unaligned.h>
+#include <asm/unwind.h>
+
+extern char __start_unwind[], __end_unwind[];
+/* extern const u8 __start_unwind_hdr[], __end_unwind_hdr[];*/
+
+/* #define UNWIND_DEBUG */
+
+#ifdef UNWIND_DEBUG
+int dbg_unw;
+#define unw_debug(fmt, ...) \
+do { \
+ if (dbg_unw) \
+ pr_info(fmt, ##__VA_ARGS__); \
+} while (0);
+#else
+#define unw_debug(fmt, ...)
+#endif
+
+#define MAX_STACK_DEPTH 8
+
+#define EXTRA_INFO(f) { \
+ BUILD_BUG_ON_ZERO(offsetof(struct unwind_frame_info, f) \
+ % sizeof_field(struct unwind_frame_info, f)) \
+ + offsetof(struct unwind_frame_info, f) \
+ / sizeof_field(struct unwind_frame_info, f), \
+ sizeof_field(struct unwind_frame_info, f) \
+ }
+#define PTREGS_INFO(f) EXTRA_INFO(regs.f)
+
+static const struct {
+ unsigned offs:BITS_PER_LONG / 2;
+ unsigned width:BITS_PER_LONG / 2;
+} reg_info[] = {
+UNW_REGISTER_INFO};
+
+#undef PTREGS_INFO
+#undef EXTRA_INFO
+
+#ifndef REG_INVALID
+#define REG_INVALID(r) (reg_info[r].width == 0)
+#endif
+
+#define DW_CFA_nop 0x00
+#define DW_CFA_set_loc 0x01
+#define DW_CFA_advance_loc1 0x02
+#define DW_CFA_advance_loc2 0x03
+#define DW_CFA_advance_loc4 0x04
+#define DW_CFA_offset_extended 0x05
+#define DW_CFA_restore_extended 0x06
+#define DW_CFA_undefined 0x07
+#define DW_CFA_same_value 0x08
+#define DW_CFA_register 0x09
+#define DW_CFA_remember_state 0x0a
+#define DW_CFA_restore_state 0x0b
+#define DW_CFA_def_cfa 0x0c
+#define DW_CFA_def_cfa_register 0x0d
+#define DW_CFA_def_cfa_offset 0x0e
+#define DW_CFA_def_cfa_expression 0x0f
+#define DW_CFA_expression 0x10
+#define DW_CFA_offset_extended_sf 0x11
+#define DW_CFA_def_cfa_sf 0x12
+#define DW_CFA_def_cfa_offset_sf 0x13
+#define DW_CFA_val_offset 0x14
+#define DW_CFA_val_offset_sf 0x15
+#define DW_CFA_val_expression 0x16
+#define DW_CFA_lo_user 0x1c
+#define DW_CFA_GNU_window_save 0x2d
+#define DW_CFA_GNU_args_size 0x2e
+#define DW_CFA_GNU_negative_offset_extended 0x2f
+#define DW_CFA_hi_user 0x3f
+
+#define DW_EH_PE_FORM 0x07
+#define DW_EH_PE_native 0x00
+#define DW_EH_PE_leb128 0x01
+#define DW_EH_PE_data2 0x02
+#define DW_EH_PE_data4 0x03
+#define DW_EH_PE_data8 0x04
+#define DW_EH_PE_signed 0x08
+#define DW_EH_PE_ADJUST 0x70
+#define DW_EH_PE_abs 0x00
+#define DW_EH_PE_pcrel 0x10
+#define DW_EH_PE_textrel 0x20
+#define DW_EH_PE_datarel 0x30
+#define DW_EH_PE_funcrel 0x40
+#define DW_EH_PE_aligned 0x50
+#define DW_EH_PE_indirect 0x80
+#define DW_EH_PE_omit 0xff
+
+#define CIE_ID 0
+
+typedef unsigned long uleb128_t;
+typedef signed long sleb128_t;
+
+static struct unwind_table {
+ struct {
+ unsigned long pc;
+ unsigned long range;
+ } core, init;
+ const void *address;
+ unsigned long size;
+ const unsigned char *header;
+ unsigned long hdrsz;
+ struct unwind_table *link;
+ const char *name;
+} root_table;
+
+struct unwind_item {
+ enum item_location {
+ Nowhere,
+ Memory,
+ Register,
+ Value
+ } where;
+ uleb128_t value;
+};
+
+struct unwind_state {
+ uleb128_t loc, org;
+ const u8 *cieStart, *cieEnd;
+ uleb128_t codeAlign;
+ sleb128_t dataAlign;
+ struct cfa {
+ uleb128_t reg, offs;
+ } cfa;
+ struct unwind_item regs[ARRAY_SIZE(reg_info)];
+ unsigned stackDepth:8;
+ unsigned version:8;
+ const u8 *label;
+ const u8 *stack[MAX_STACK_DEPTH];
+};
+
+static const struct cfa badCFA = { ARRAY_SIZE(reg_info), 1 };
+
+static struct unwind_table *find_table(unsigned long pc)
+{
+ struct unwind_table *table;
+
+ for (table = &root_table; table; table = table->link)
+ if ((pc >= table->core.pc
+ && pc < table->core.pc + table->core.range)
+ || (pc >= table->init.pc
+ && pc < table->init.pc + table->init.range))
+ break;
+
+ return table;
+}
+
+static unsigned long read_pointer(const u8 **pLoc,
+ const void *end, signed ptrType);
+static void init_unwind_hdr(struct unwind_table *table,
+ void *(*alloc) (unsigned long));
+
+/*
+ * wrappers for header alloc (vs. calling one vs. other at call site)
+ * to elide section mismatches warnings
+ */
+static void *__init unw_hdr_alloc_early(unsigned long sz)
+{
+ return memblock_alloc_from(sz, sizeof(unsigned int), MAX_DMA_ADDRESS);
+}
+
+static void init_unwind_table(struct unwind_table *table, const char *name,
+ const void *core_start, unsigned long core_size,
+ const void *init_start, unsigned long init_size,
+ const void *table_start, unsigned long table_size,
+ const u8 *header_start, unsigned long header_size)
+{
+ table->core.pc = (unsigned long)core_start;
+ table->core.range = core_size;
+ table->init.pc = (unsigned long)init_start;
+ table->init.range = init_size;
+ table->address = table_start;
+ table->size = table_size;
+ /* To avoid the pointer addition with NULL pointer.*/
+ if (header_start != NULL) {
+ const u8 *ptr = header_start + 4;
+ const u8 *end = header_start + header_size;
+ /* See if the linker provided table looks valid. */
+ if (header_size <= 4
+ || header_start[0] != 1
+ || (void *)read_pointer(&ptr, end, header_start[1])
+ != table_start
+ || header_start[2] == DW_EH_PE_omit
+ || read_pointer(&ptr, end, header_start[2]) <= 0
+ || header_start[3] == DW_EH_PE_omit)
+ header_start = NULL;
+ }
+ table->hdrsz = header_size;
+ smp_wmb();
+ table->header = header_start;
+ table->link = NULL;
+ table->name = name;
+}
+
+void __init arc_unwind_init(void)
+{
+ init_unwind_table(&root_table, "kernel", _text, _end - _text, NULL, 0,
+ __start_unwind, __end_unwind - __start_unwind,
+ NULL, 0);
+ /*__start_unwind_hdr, __end_unwind_hdr - __start_unwind_hdr);*/
+
+ init_unwind_hdr(&root_table, unw_hdr_alloc_early);
+}
+
+static const u32 bad_cie, not_fde;
+static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *);
+static const u32 *__cie_for_fde(const u32 *fde);
+static signed fde_pointer_type(const u32 *cie);
+
+struct eh_frame_hdr_table_entry {
+ unsigned long start, fde;
+};
+
+static int cmp_eh_frame_hdr_table_entries(const void *p1, const void *p2)
+{
+ const struct eh_frame_hdr_table_entry *e1 = p1;
+ const struct eh_frame_hdr_table_entry *e2 = p2;
+
+ return (e1->start > e2->start) - (e1->start < e2->start);
+}
+
+static void swap_eh_frame_hdr_table_entries(void *p1, void *p2, int size)
+{
+ struct eh_frame_hdr_table_entry *e1 = p1;
+ struct eh_frame_hdr_table_entry *e2 = p2;
+
+ swap(e1->start, e2->start);
+ swap(e1->fde, e2->fde);
+}
+
+static void init_unwind_hdr(struct unwind_table *table,
+ void *(*alloc) (unsigned long))
+{
+ const u8 *ptr;
+ unsigned long tableSize = table->size, hdrSize;
+ unsigned int n;
+ const u32 *fde;
+ struct {
+ u8 version;
+ u8 eh_frame_ptr_enc;
+ u8 fde_count_enc;
+ u8 table_enc;
+ unsigned long eh_frame_ptr;
+ unsigned int fde_count;
+ struct eh_frame_hdr_table_entry table[];
+ } __attribute__ ((__packed__)) *header;
+
+ if (table->header)
+ return;
+
+ if (table->hdrsz)
+ pr_warn(".eh_frame_hdr for '%s' present but unusable\n",
+ table->name);
+
+ if (tableSize & (sizeof(*fde) - 1))
+ return;
+
+ for (fde = table->address, n = 0;
+ tableSize > sizeof(*fde) && tableSize - sizeof(*fde) >= *fde;
+ tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) {
+ const u32 *cie = cie_for_fde(fde, table);
+ signed ptrType;
+
+ if (cie == &not_fde)
+ continue;
+ if (cie == NULL || cie == &bad_cie)
+ goto ret_err;
+ ptrType = fde_pointer_type(cie);
+ if (ptrType < 0)
+ goto ret_err;
+
+ ptr = (const u8 *)(fde + 2);
+ if (!read_pointer(&ptr, (const u8 *)(fde + 1) + *fde,
+ ptrType)) {
+ /* FIXME_Rajesh We have 4 instances of null addresses
+ * instead of the initial loc addr
+ * return;
+ */
+ WARN(1, "unwinder: FDE->initial_location NULL %p\n",
+ (const u8 *)(fde + 1) + *fde);
+ }
+ ++n;
+ }
+
+ if (tableSize || !n)
+ goto ret_err;
+
+ hdrSize = 4 + sizeof(unsigned long) + sizeof(unsigned int)
+ + 2 * n * sizeof(unsigned long);
+
+ header = alloc(hdrSize);
+ if (!header)
+ goto ret_err;
+
+ header->version = 1;
+ header->eh_frame_ptr_enc = DW_EH_PE_abs | DW_EH_PE_native;
+ header->fde_count_enc = DW_EH_PE_abs | DW_EH_PE_data4;
+ header->table_enc = DW_EH_PE_abs | DW_EH_PE_native;
+ put_unaligned((unsigned long)table->address, &header->eh_frame_ptr);
+ BUILD_BUG_ON(offsetof(typeof(*header), fde_count)
+ % __alignof(typeof(header->fde_count)));
+ header->fde_count = n;
+
+ BUILD_BUG_ON(offsetof(typeof(*header), table)
+ % __alignof(typeof(*header->table)));
+ for (fde = table->address, tableSize = table->size, n = 0;
+ tableSize;
+ tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) {
+ const u32 *cie = __cie_for_fde(fde);
+
+ if (fde[1] == CIE_ID)
+ continue; /* this is a CIE */
+ ptr = (const u8 *)(fde + 2);
+ header->table[n].start = read_pointer(&ptr,
+ (const u8 *)(fde + 1) +
+ *fde,
+ fde_pointer_type(cie));
+ header->table[n].fde = (unsigned long)fde;
+ ++n;
+ }
+ WARN_ON(n != header->fde_count);
+
+ sort(header->table,
+ n,
+ sizeof(*header->table),
+ cmp_eh_frame_hdr_table_entries, swap_eh_frame_hdr_table_entries);
+
+ table->hdrsz = hdrSize;
+ smp_wmb();
+ table->header = (const void *)header;
+ return;
+
+ret_err:
+ panic("Attention !!! Dwarf FDE parsing errors\n");
+}
+
+#ifdef CONFIG_MODULES
+static void *unw_hdr_alloc(unsigned long sz)
+{
+ return kmalloc(sz, GFP_KERNEL);
+}
+
+static struct unwind_table *last_table;
+
+/* Must be called with module_mutex held. */
+void *unwind_add_table(struct module *module, const void *table_start,
+ unsigned long table_size)
+{
+ struct unwind_table *table;
+ struct module_memory *core_text;
+ struct module_memory *init_text;
+
+ if (table_size <= 0)
+ return NULL;
+
+ table = kmalloc(sizeof(*table), GFP_KERNEL);
+ if (!table)
+ return NULL;
+
+ core_text = &module->mem[MOD_TEXT];
+ init_text = &module->mem[MOD_INIT_TEXT];
+
+ init_unwind_table(table, module->name, core_text->base, core_text->size,
+ init_text->base, init_text->size, table_start, table_size, NULL, 0);
+
+ init_unwind_hdr(table, unw_hdr_alloc);
+
+#ifdef UNWIND_DEBUG
+ unw_debug("Table added for [%s] %lx %lx\n",
+ module->name, table->core.pc, table->core.range);
+#endif
+ if (last_table)
+ last_table->link = table;
+ else
+ root_table.link = table;
+ last_table = table;
+
+ return table;
+}
+
+struct unlink_table_info {
+ struct unwind_table *table;
+ int init_only;
+};
+
+static int unlink_table(void *arg)
+{
+ struct unlink_table_info *info = arg;
+ struct unwind_table *table = info->table, *prev;
+
+ for (prev = &root_table; prev->link && prev->link != table;
+ prev = prev->link)
+ ;
+
+ if (prev->link) {
+ if (info->init_only) {
+ table->init.pc = 0;
+ table->init.range = 0;
+ info->table = NULL;
+ } else {
+ prev->link = table->link;
+ if (!prev->link)
+ last_table = prev;
+ }
+ } else
+ info->table = NULL;
+
+ return 0;
+}
+
+/* Must be called with module_mutex held. */
+void unwind_remove_table(void *handle, int init_only)
+{
+ struct unwind_table *table = handle;
+ struct unlink_table_info info;
+
+ if (!table || table == &root_table)
+ return;
+
+ if (init_only && table == last_table) {
+ table->init.pc = 0;
+ table->init.range = 0;
+ return;
+ }
+
+ info.table = table;
+ info.init_only = init_only;
+
+ unlink_table(&info); /* XXX: SMP */
+ kfree(table->header);
+ kfree(table);
+}
+
+#endif /* CONFIG_MODULES */
+
+static uleb128_t get_uleb128(const u8 **pcur, const u8 *end)
+{
+ const u8 *cur = *pcur;
+ uleb128_t value;
+ unsigned int shift;
+
+ for (shift = 0, value = 0; cur < end; shift += 7) {
+ if (shift + 7 > 8 * sizeof(value)
+ && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) {
+ cur = end + 1;
+ break;
+ }
+ value |= (uleb128_t) (*cur & 0x7f) << shift;
+ if (!(*cur++ & 0x80))
+ break;
+ }
+ *pcur = cur;
+
+ return value;
+}
+
+static sleb128_t get_sleb128(const u8 **pcur, const u8 *end)
+{
+ const u8 *cur = *pcur;
+ sleb128_t value;
+ unsigned int shift;
+
+ for (shift = 0, value = 0; cur < end; shift += 7) {
+ if (shift + 7 > 8 * sizeof(value)
+ && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) {
+ cur = end + 1;
+ break;
+ }
+ value |= (sleb128_t) (*cur & 0x7f) << shift;
+ if (!(*cur & 0x80)) {
+ value |= -(*cur++ & 0x40) << shift;
+ break;
+ }
+ }
+ *pcur = cur;
+
+ return value;
+}
+
+static const u32 *__cie_for_fde(const u32 *fde)
+{
+ const u32 *cie;
+
+ cie = fde + 1 - fde[1] / sizeof(*fde);
+
+ return cie;
+}
+
+static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *table)
+{
+ const u32 *cie;
+
+ if (!*fde || (*fde & (sizeof(*fde) - 1)))
+ return &bad_cie;
+
+ if (fde[1] == CIE_ID)
+ return &not_fde; /* this is a CIE */
+
+ if ((fde[1] & (sizeof(*fde) - 1)))
+/* || fde[1] > (unsigned long)(fde + 1) - (unsigned long)table->address) */
+ return NULL; /* this is not a valid FDE */
+
+ cie = __cie_for_fde(fde);
+
+ if (*cie <= sizeof(*cie) + 4 || *cie >= fde[1] - sizeof(*fde)
+ || (*cie & (sizeof(*cie) - 1))
+ || (cie[1] != CIE_ID))
+ return NULL; /* this is not a (valid) CIE */
+ return cie;
+}
+
+static unsigned long read_pointer(const u8 **pLoc, const void *end,
+ signed ptrType)
+{
+ unsigned long value = 0;
+ union {
+ const u8 *p8;
+ const u16 *p16u;
+ const s16 *p16s;
+ const u32 *p32u;
+ const s32 *p32s;
+ const unsigned long *pul;
+ } ptr;
+
+ if (ptrType < 0 || ptrType == DW_EH_PE_omit)
+ return 0;
+ ptr.p8 = *pLoc;
+ switch (ptrType & DW_EH_PE_FORM) {
+ case DW_EH_PE_data2:
+ if (end < (const void *)(ptr.p16u + 1))
+ return 0;
+ if (ptrType & DW_EH_PE_signed)
+ value = get_unaligned((u16 *) ptr.p16s++);
+ else
+ value = get_unaligned((u16 *) ptr.p16u++);
+ break;
+ case DW_EH_PE_data4:
+#ifdef CONFIG_64BIT
+ if (end < (const void *)(ptr.p32u + 1))
+ return 0;
+ if (ptrType & DW_EH_PE_signed)
+ value = get_unaligned(ptr.p32s++);
+ else
+ value = get_unaligned(ptr.p32u++);
+ break;
+ case DW_EH_PE_data8:
+ BUILD_BUG_ON(sizeof(u64) != sizeof(value));
+#else
+ BUILD_BUG_ON(sizeof(u32) != sizeof(value));
+#endif
+ fallthrough;
+ case DW_EH_PE_native:
+ if (end < (const void *)(ptr.pul + 1))
+ return 0;
+ value = get_unaligned((unsigned long *)ptr.pul++);
+ break;
+ case DW_EH_PE_leb128:
+ BUILD_BUG_ON(sizeof(uleb128_t) > sizeof(value));
+ value = ptrType & DW_EH_PE_signed ? get_sleb128(&ptr.p8, end)
+ : get_uleb128(&ptr.p8, end);
+ if ((const void *)ptr.p8 > end)
+ return 0;
+ break;
+ default:
+ return 0;
+ }
+ switch (ptrType & DW_EH_PE_ADJUST) {
+ case DW_EH_PE_abs:
+ break;
+ case DW_EH_PE_pcrel:
+ value += (unsigned long)*pLoc;
+ break;
+ default:
+ return 0;
+ }
+ if ((ptrType & DW_EH_PE_indirect)
+ && __get_user(value, (unsigned long __user *)value))
+ return 0;
+ *pLoc = ptr.p8;
+
+ return value;
+}
+
+static signed fde_pointer_type(const u32 *cie)
+{
+ const u8 *ptr = (const u8 *)(cie + 2);
+ unsigned int version = *ptr;
+
+ if (*++ptr) {
+ const char *aug;
+ const u8 *end = (const u8 *)(cie + 1) + *cie;
+ uleb128_t len;
+
+ /* check if augmentation size is first (and thus present) */
+ if (*ptr != 'z')
+ return -1;
+
+ /* check if augmentation string is nul-terminated */
+ aug = (const void *)ptr;
+ ptr = memchr(aug, 0, end - ptr);
+ if (ptr == NULL)
+ return -1;
+
+ ++ptr; /* skip terminator */
+ get_uleb128(&ptr, end); /* skip code alignment */
+ get_sleb128(&ptr, end); /* skip data alignment */
+ /* skip return address column */
+ version <= 1 ? (void) ++ptr : (void)get_uleb128(&ptr, end);
+ len = get_uleb128(&ptr, end); /* augmentation length */
+
+ if (ptr + len < ptr || ptr + len > end)
+ return -1;
+
+ end = ptr + len;
+ while (*++aug) {
+ if (ptr >= end)
+ return -1;
+ switch (*aug) {
+ case 'L':
+ ++ptr;
+ break;
+ case 'P':{
+ signed ptrType = *ptr++;
+
+ if (!read_pointer(&ptr, end, ptrType)
+ || ptr > end)
+ return -1;
+ }
+ break;
+ case 'R':
+ return *ptr;
+ default:
+ return -1;
+ }
+ }
+ }
+ return DW_EH_PE_native | DW_EH_PE_abs;
+}
+
+static int advance_loc(unsigned long delta, struct unwind_state *state)
+{
+ state->loc += delta * state->codeAlign;
+
+ /* FIXME_Rajesh: Probably we are defining for the initial range as well;
+ return delta > 0;
+ */
+ unw_debug("delta %3lu => loc 0x%lx: ", delta, state->loc);
+ return 1;
+}
+
+static void set_rule(uleb128_t reg, enum item_location where, uleb128_t value,
+ struct unwind_state *state)
+{
+ if (reg < ARRAY_SIZE(state->regs)) {
+ state->regs[reg].where = where;
+ state->regs[reg].value = value;
+
+#ifdef UNWIND_DEBUG
+ unw_debug("r%lu: ", reg);
+ switch (where) {
+ case Nowhere:
+ unw_debug("s ");
+ break;
+ case Memory:
+ unw_debug("c(%lu) ", value);
+ break;
+ case Register:
+ unw_debug("r(%lu) ", value);
+ break;
+ case Value:
+ unw_debug("v(%lu) ", value);
+ break;
+ default:
+ break;
+ }
+#endif
+ }
+}
+
+static int processCFI(const u8 *start, const u8 *end, unsigned long targetLoc,
+ signed ptrType, struct unwind_state *state)
+{
+ union {
+ const u8 *p8;
+ const u16 *p16;
+ const u32 *p32;
+ } ptr;
+ int result = 1;
+ u8 opcode;
+
+ if (start != state->cieStart) {
+ state->loc = state->org;
+ result =
+ processCFI(state->cieStart, state->cieEnd, 0, ptrType,
+ state);
+ if (targetLoc == 0 && state->label == NULL)
+ return result;
+ }
+ for (ptr.p8 = start; result && ptr.p8 < end;) {
+ switch (*ptr.p8 >> 6) {
+ uleb128_t value;
+
+ case 0:
+ opcode = *ptr.p8++;
+
+ switch (opcode) {
+ case DW_CFA_nop:
+ unw_debug("cfa nop ");
+ break;
+ case DW_CFA_set_loc:
+ state->loc = read_pointer(&ptr.p8, end,
+ ptrType);
+ if (state->loc == 0)
+ result = 0;
+ unw_debug("cfa_set_loc: 0x%lx ", state->loc);
+ break;
+ case DW_CFA_advance_loc1:
+ unw_debug("\ncfa advance loc1:");
+ result = ptr.p8 < end
+ && advance_loc(*ptr.p8++, state);
+ break;
+ case DW_CFA_advance_loc2:
+ value = *ptr.p8++;
+ value += *ptr.p8++ << 8;
+ unw_debug("\ncfa advance loc2:");
+ result = ptr.p8 <= end + 2
+ /* && advance_loc(*ptr.p16++, state); */
+ && advance_loc(value, state);
+ break;
+ case DW_CFA_advance_loc4:
+ unw_debug("\ncfa advance loc4:");
+ result = ptr.p8 <= end + 4
+ && advance_loc(*ptr.p32++, state);
+ break;
+ case DW_CFA_offset_extended:
+ value = get_uleb128(&ptr.p8, end);
+ unw_debug("cfa_offset_extended: ");
+ set_rule(value, Memory,
+ get_uleb128(&ptr.p8, end), state);
+ break;
+ case DW_CFA_val_offset:
+ value = get_uleb128(&ptr.p8, end);
+ set_rule(value, Value,
+ get_uleb128(&ptr.p8, end), state);
+ break;
+ case DW_CFA_offset_extended_sf:
+ value = get_uleb128(&ptr.p8, end);
+ set_rule(value, Memory,
+ get_sleb128(&ptr.p8, end), state);
+ break;
+ case DW_CFA_val_offset_sf:
+ value = get_uleb128(&ptr.p8, end);
+ set_rule(value, Value,
+ get_sleb128(&ptr.p8, end), state);
+ break;
+ case DW_CFA_restore_extended:
+ unw_debug("cfa_restore_extended: ");
+ case DW_CFA_undefined:
+ unw_debug("cfa_undefined: ");
+ case DW_CFA_same_value:
+ unw_debug("cfa_same_value: ");
+ set_rule(get_uleb128(&ptr.p8, end), Nowhere, 0,
+ state);
+ break;
+ case DW_CFA_register:
+ unw_debug("cfa_register: ");
+ value = get_uleb128(&ptr.p8, end);
+ set_rule(value,
+ Register,
+ get_uleb128(&ptr.p8, end), state);
+ break;
+ case DW_CFA_remember_state:
+ unw_debug("cfa_remember_state: ");
+ if (ptr.p8 == state->label) {
+ state->label = NULL;
+ return 1;
+ }
+ if (state->stackDepth >= MAX_STACK_DEPTH)
+ return 0;
+ state->stack[state->stackDepth++] = ptr.p8;
+ break;
+ case DW_CFA_restore_state:
+ unw_debug("cfa_restore_state: ");
+ if (state->stackDepth) {
+ const uleb128_t loc = state->loc;
+ const u8 *label = state->label;
+
+ state->label =
+ state->stack[state->stackDepth - 1];
+ memcpy(&state->cfa, &badCFA,
+ sizeof(state->cfa));
+ memset(state->regs, 0,
+ sizeof(state->regs));
+ state->stackDepth = 0;
+ result =
+ processCFI(start, end, 0, ptrType,
+ state);
+ state->loc = loc;
+ state->label = label;
+ } else
+ return 0;
+ break;
+ case DW_CFA_def_cfa:
+ state->cfa.reg = get_uleb128(&ptr.p8, end);
+ unw_debug("cfa_def_cfa: r%lu ", state->cfa.reg);
+ fallthrough;
+ case DW_CFA_def_cfa_offset:
+ state->cfa.offs = get_uleb128(&ptr.p8, end);
+ unw_debug("cfa_def_cfa_offset: 0x%lx ",
+ state->cfa.offs);
+ break;
+ case DW_CFA_def_cfa_sf:
+ state->cfa.reg = get_uleb128(&ptr.p8, end);
+ fallthrough;
+ case DW_CFA_def_cfa_offset_sf:
+ state->cfa.offs = get_sleb128(&ptr.p8, end)
+ * state->dataAlign;
+ break;
+ case DW_CFA_def_cfa_register:
+ unw_debug("cfa_def_cfa_register: ");
+ state->cfa.reg = get_uleb128(&ptr.p8, end);
+ break;
+ /*todo case DW_CFA_def_cfa_expression: */
+ /*todo case DW_CFA_expression: */
+ /*todo case DW_CFA_val_expression: */
+ case DW_CFA_GNU_args_size:
+ get_uleb128(&ptr.p8, end);
+ break;
+ case DW_CFA_GNU_negative_offset_extended:
+ value = get_uleb128(&ptr.p8, end);
+ set_rule(value,
+ Memory,
+ (uleb128_t) 0 - get_uleb128(&ptr.p8,
+ end),
+ state);
+ break;
+ case DW_CFA_GNU_window_save:
+ default:
+ unw_debug("UNKNOWN OPCODE 0x%x\n", opcode);
+ result = 0;
+ break;
+ }
+ break;
+ case 1:
+ unw_debug("\ncfa_adv_loc: ");
+ result = advance_loc(*ptr.p8++ & 0x3f, state);
+ break;
+ case 2:
+ unw_debug("cfa_offset: ");
+ value = *ptr.p8++ & 0x3f;
+ set_rule(value, Memory, get_uleb128(&ptr.p8, end),
+ state);
+ break;
+ case 3:
+ unw_debug("cfa_restore: ");
+ set_rule(*ptr.p8++ & 0x3f, Nowhere, 0, state);
+ break;
+ }
+
+ if (ptr.p8 > end)
+ result = 0;
+ if (result && targetLoc != 0 && targetLoc < state->loc)
+ return 1;
+ }
+
+ return result && ptr.p8 == end && (targetLoc == 0 || (
+ /*todo While in theory this should apply, gcc in practice omits
+ everything past the function prolog, and hence the location
+ never reaches the end of the function.
+ targetLoc < state->loc && */ state->label == NULL));
+}
+
+/* Unwind to previous to frame. Returns 0 if successful, negative
+ * number in case of an error. */
+int arc_unwind(struct unwind_frame_info *frame)
+{
+#define FRAME_REG(r, t) (((t *)frame)[reg_info[r].offs])
+ const u32 *fde = NULL, *cie = NULL;
+ const u8 *ptr = NULL, *end = NULL;
+ unsigned long pc = UNW_PC(frame) - frame->call_frame;
+ unsigned long startLoc = 0, endLoc = 0, cfa;
+ unsigned int i;
+ signed ptrType = -1;
+ uleb128_t retAddrReg = 0;
+ const struct unwind_table *table;
+ struct unwind_state state;
+ unsigned long *fptr;
+ unsigned long addr;
+
+ unw_debug("\n\nUNWIND FRAME:\n");
+ unw_debug("PC: 0x%lx BLINK: 0x%lx, SP: 0x%lx, FP: 0x%x\n",
+ UNW_PC(frame), UNW_BLINK(frame), UNW_SP(frame),
+ UNW_FP(frame));
+
+ if (UNW_PC(frame) == 0)
+ return -EINVAL;
+
+#ifdef UNWIND_DEBUG
+ {
+ unsigned long *sptr = (unsigned long *)UNW_SP(frame);
+ unw_debug("\nStack Dump:\n");
+ for (i = 0; i < 20; i++, sptr++)
+ unw_debug("0x%p: 0x%lx\n", sptr, *sptr);
+ unw_debug("\n");
+ }
+#endif
+
+ table = find_table(pc);
+ if (table != NULL
+ && !(table->size & (sizeof(*fde) - 1))) {
+ const u8 *hdr = table->header;
+ unsigned long tableSize;
+
+ smp_rmb();
+ if (hdr && hdr[0] == 1) {
+ switch (hdr[3] & DW_EH_PE_FORM) {
+ case DW_EH_PE_native:
+ tableSize = sizeof(unsigned long);
+ break;
+ case DW_EH_PE_data2:
+ tableSize = 2;
+ break;
+ case DW_EH_PE_data4:
+ tableSize = 4;
+ break;
+ case DW_EH_PE_data8:
+ tableSize = 8;
+ break;
+ default:
+ tableSize = 0;
+ break;
+ }
+ ptr = hdr + 4;
+ end = hdr + table->hdrsz;
+ if (tableSize && read_pointer(&ptr, end, hdr[1])
+ == (unsigned long)table->address
+ && (i = read_pointer(&ptr, end, hdr[2])) > 0
+ && i == (end - ptr) / (2 * tableSize)
+ && !((end - ptr) % (2 * tableSize))) {
+ do {
+ const u8 *cur =
+ ptr + (i / 2) * (2 * tableSize);
+
+ startLoc = read_pointer(&cur,
+ cur + tableSize,
+ hdr[3]);
+ if (pc < startLoc)
+ i /= 2;
+ else {
+ ptr = cur - tableSize;
+ i = (i + 1) / 2;
+ }
+ } while (startLoc && i > 1);
+ if (i == 1
+ && (startLoc = read_pointer(&ptr,
+ ptr + tableSize,
+ hdr[3])) != 0
+ && pc >= startLoc)
+ fde = (void *)read_pointer(&ptr,
+ ptr +
+ tableSize,
+ hdr[3]);
+ }
+ }
+
+ if (fde != NULL) {
+ cie = cie_for_fde(fde, table);
+ ptr = (const u8 *)(fde + 2);
+ if (cie != NULL
+ && cie != &bad_cie
+ && cie != &not_fde
+ && (ptrType = fde_pointer_type(cie)) >= 0
+ && read_pointer(&ptr,
+ (const u8 *)(fde + 1) + *fde,
+ ptrType) == startLoc) {
+ if (!(ptrType & DW_EH_PE_indirect))
+ ptrType &=
+ DW_EH_PE_FORM | DW_EH_PE_signed;
+ endLoc =
+ startLoc + read_pointer(&ptr,
+ (const u8 *)(fde +
+ 1) +
+ *fde, ptrType);
+ if (pc >= endLoc) {
+ fde = NULL;
+ cie = NULL;
+ }
+ } else {
+ fde = NULL;
+ cie = NULL;
+ }
+ }
+ }
+ if (cie != NULL) {
+ memset(&state, 0, sizeof(state));
+ state.cieEnd = ptr; /* keep here temporarily */
+ ptr = (const u8 *)(cie + 2);
+ end = (const u8 *)(cie + 1) + *cie;
+ frame->call_frame = 1;
+ if (*++ptr) {
+ /* check if augmentation size is first (thus present) */
+ if (*ptr == 'z') {
+ while (++ptr < end && *ptr) {
+ switch (*ptr) {
+ /* chk for ignorable or already handled
+ * nul-terminated augmentation string */
+ case 'L':
+ case 'P':
+ case 'R':
+ continue;
+ case 'S':
+ frame->call_frame = 0;
+ continue;
+ default:
+ break;
+ }
+ break;
+ }
+ }
+ if (ptr >= end || *ptr)
+ cie = NULL;
+ }
+ ++ptr;
+ }
+ if (cie != NULL) {
+ /* get code alignment factor */
+ state.codeAlign = get_uleb128(&ptr, end);
+ /* get data alignment factor */
+ state.dataAlign = get_sleb128(&ptr, end);
+ if (state.codeAlign == 0 || state.dataAlign == 0 || ptr >= end)
+ cie = NULL;
+ else {
+ retAddrReg =
+ state.version <= 1 ? *ptr++ : get_uleb128(&ptr,
+ end);
+ unw_debug("CIE Frame Info:\n");
+ unw_debug("return Address register 0x%lx\n",
+ retAddrReg);
+ unw_debug("data Align: %ld\n", state.dataAlign);
+ unw_debug("code Align: %lu\n", state.codeAlign);
+ /* skip augmentation */
+ if (((const char *)(cie + 2))[1] == 'z') {
+ uleb128_t augSize = get_uleb128(&ptr, end);
+
+ ptr += augSize;
+ }
+ if (ptr > end || retAddrReg >= ARRAY_SIZE(reg_info)
+ || REG_INVALID(retAddrReg)
+ || reg_info[retAddrReg].width !=
+ sizeof(unsigned long))
+ cie = NULL;
+ }
+ }
+ if (cie != NULL) {
+ state.cieStart = ptr;
+ ptr = state.cieEnd;
+ state.cieEnd = end;
+ end = (const u8 *)(fde + 1) + *fde;
+ /* skip augmentation */
+ if (((const char *)(cie + 2))[1] == 'z') {
+ uleb128_t augSize = get_uleb128(&ptr, end);
+
+ if ((ptr += augSize) > end)
+ fde = NULL;
+ }
+ }
+ if (cie == NULL || fde == NULL) {
+#ifdef CONFIG_FRAME_POINTER
+ unsigned long top, bottom;
+
+ top = STACK_TOP_UNW(frame->task);
+ bottom = STACK_BOTTOM_UNW(frame->task);
+#if FRAME_RETADDR_OFFSET < 0
+ if (UNW_SP(frame) < top && UNW_FP(frame) <= UNW_SP(frame)
+ && bottom < UNW_FP(frame)
+#else
+ if (UNW_SP(frame) > top && UNW_FP(frame) >= UNW_SP(frame)
+ && bottom > UNW_FP(frame)
+#endif
+ && !((UNW_SP(frame) | UNW_FP(frame))
+ & (sizeof(unsigned long) - 1))) {
+ unsigned long link;
+
+ if (!__get_user(link, (unsigned long *)
+ (UNW_FP(frame) + FRAME_LINK_OFFSET))
+#if FRAME_RETADDR_OFFSET < 0
+ && link > bottom && link < UNW_FP(frame)
+#else
+ && link > UNW_FP(frame) && link < bottom
+#endif
+ && !(link & (sizeof(link) - 1))
+ && !__get_user(UNW_PC(frame),
+ (unsigned long *)(UNW_FP(frame)
+ + FRAME_RETADDR_OFFSET)))
+ {
+ UNW_SP(frame) =
+ UNW_FP(frame) + FRAME_RETADDR_OFFSET
+#if FRAME_RETADDR_OFFSET < 0
+ -
+#else
+ +
+#endif
+ sizeof(UNW_PC(frame));
+ UNW_FP(frame) = link;
+ return 0;
+ }
+ }
+#endif
+ return -ENXIO;
+ }
+ state.org = startLoc;
+ memcpy(&state.cfa, &badCFA, sizeof(state.cfa));
+
+ unw_debug("\nProcess instructions\n");
+
+ /* process instructions
+ * For ARC, we optimize by having blink(retAddrReg) with
+ * the sameValue in the leaf function, so we should not check
+ * state.regs[retAddrReg].where == Nowhere
+ */
+ if (!processCFI(ptr, end, pc, ptrType, &state)
+ || state.loc > endLoc
+/* || state.regs[retAddrReg].where == Nowhere */
+ || state.cfa.reg >= ARRAY_SIZE(reg_info)
+ || reg_info[state.cfa.reg].width != sizeof(unsigned long)
+ || state.cfa.offs % sizeof(unsigned long))
+ return -EIO;
+
+#ifdef UNWIND_DEBUG
+ unw_debug("\n");
+
+ unw_debug("\nRegister State Based on the rules parsed from FDE:\n");
+ for (i = 0; i < ARRAY_SIZE(state.regs); ++i) {
+
+ if (REG_INVALID(i))
+ continue;
+
+ switch (state.regs[i].where) {
+ case Nowhere:
+ break;
+ case Memory:
+ unw_debug(" r%d: c(%lu),", i, state.regs[i].value);
+ break;
+ case Register:
+ unw_debug(" r%d: r(%lu),", i, state.regs[i].value);
+ break;
+ case Value:
+ unw_debug(" r%d: v(%lu),", i, state.regs[i].value);
+ break;
+ }
+ }
+
+ unw_debug("\n");
+#endif
+
+ /* update frame */
+ if (frame->call_frame
+ && !UNW_DEFAULT_RA(state.regs[retAddrReg], state.dataAlign))
+ frame->call_frame = 0;
+ cfa = FRAME_REG(state.cfa.reg, unsigned long) + state.cfa.offs;
+ startLoc = min_t(unsigned long, UNW_SP(frame), cfa);
+ endLoc = max_t(unsigned long, UNW_SP(frame), cfa);
+ if (STACK_LIMIT(startLoc) != STACK_LIMIT(endLoc)) {
+ startLoc = min(STACK_LIMIT(cfa), cfa);
+ endLoc = max(STACK_LIMIT(cfa), cfa);
+ }
+
+ unw_debug("\nCFA reg: 0x%lx, offset: 0x%lx => 0x%lx\n",
+ state.cfa.reg, state.cfa.offs, cfa);
+
+ for (i = 0; i < ARRAY_SIZE(state.regs); ++i) {
+ if (REG_INVALID(i)) {
+ if (state.regs[i].where == Nowhere)
+ continue;
+ return -EIO;
+ }
+ switch (state.regs[i].where) {
+ default:
+ break;
+ case Register:
+ if (state.regs[i].value >= ARRAY_SIZE(reg_info)
+ || REG_INVALID(state.regs[i].value)
+ || reg_info[i].width >
+ reg_info[state.regs[i].value].width)
+ return -EIO;
+ switch (reg_info[state.regs[i].value].width) {
+ case sizeof(u8):
+ state.regs[i].value =
+ FRAME_REG(state.regs[i].value, const u8);
+ break;
+ case sizeof(u16):
+ state.regs[i].value =
+ FRAME_REG(state.regs[i].value, const u16);
+ break;
+ case sizeof(u32):
+ state.regs[i].value =
+ FRAME_REG(state.regs[i].value, const u32);
+ break;
+#ifdef CONFIG_64BIT
+ case sizeof(u64):
+ state.regs[i].value =
+ FRAME_REG(state.regs[i].value, const u64);
+ break;
+#endif
+ default:
+ return -EIO;
+ }
+ break;
+ }
+ }
+
+ unw_debug("\nRegister state after evaluation with realtime Stack:\n");
+ fptr = (unsigned long *)(&frame->regs);
+ for (i = 0; i < ARRAY_SIZE(state.regs); ++i, fptr++) {
+
+ if (REG_INVALID(i))
+ continue;
+ switch (state.regs[i].where) {
+ case Nowhere:
+ if (reg_info[i].width != sizeof(UNW_SP(frame))
+ || &FRAME_REG(i, __typeof__(UNW_SP(frame)))
+ != &UNW_SP(frame))
+ continue;
+ UNW_SP(frame) = cfa;
+ break;
+ case Register:
+ switch (reg_info[i].width) {
+ case sizeof(u8):
+ FRAME_REG(i, u8) = state.regs[i].value;
+ break;
+ case sizeof(u16):
+ FRAME_REG(i, u16) = state.regs[i].value;
+ break;
+ case sizeof(u32):
+ FRAME_REG(i, u32) = state.regs[i].value;
+ break;
+#ifdef CONFIG_64BIT
+ case sizeof(u64):
+ FRAME_REG(i, u64) = state.regs[i].value;
+ break;
+#endif
+ default:
+ return -EIO;
+ }
+ break;
+ case Value:
+ if (reg_info[i].width != sizeof(unsigned long))
+ return -EIO;
+ FRAME_REG(i, unsigned long) = cfa + state.regs[i].value
+ * state.dataAlign;
+ break;
+ case Memory:
+ addr = cfa + state.regs[i].value * state.dataAlign;
+
+ if ((state.regs[i].value * state.dataAlign)
+ % sizeof(unsigned long)
+ || addr < startLoc
+ || addr + sizeof(unsigned long) < addr
+ || addr + sizeof(unsigned long) > endLoc)
+ return -EIO;
+
+ switch (reg_info[i].width) {
+ case sizeof(u8):
+ __get_user(FRAME_REG(i, u8),
+ (u8 __user *)addr);
+ break;
+ case sizeof(u16):
+ __get_user(FRAME_REG(i, u16),
+ (u16 __user *)addr);
+ break;
+ case sizeof(u32):
+ __get_user(FRAME_REG(i, u32),
+ (u32 __user *)addr);
+ break;
+#ifdef CONFIG_64BIT
+ case sizeof(u64):
+ __get_user(FRAME_REG(i, u64),
+ (u64 __user *)addr);
+ break;
+#endif
+ default:
+ return -EIO;
+ }
+
+ break;
+ }
+ unw_debug("r%d: 0x%lx ", i, *fptr);
+ }
+
+ return 0;
+#undef FRAME_REG
+}
+EXPORT_SYMBOL(arc_unwind);
diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S
new file mode 100644
index 0000000000..549c3f4079
--- /dev/null
+++ b/arch/arc/kernel/vmlinux.lds.S
@@ -0,0 +1,155 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <asm-generic/vmlinux.lds.h>
+#include <asm/cache.h>
+#include <asm/page.h>
+#include <asm/thread_info.h>
+
+OUTPUT_ARCH(arc)
+ENTRY(res_service)
+
+#ifdef CONFIG_CPU_BIG_ENDIAN
+jiffies = jiffies_64 + 4;
+#else
+jiffies = jiffies_64;
+#endif
+
+SECTIONS
+{
+ /*
+ * ICCM starts at 0x8000_0000. So if kernel is relocated to some other
+ * address, make sure peripheral at 0x8z doesn't clash with ICCM
+ * Essentially vector is also in ICCM.
+ */
+
+ . = CONFIG_LINUX_LINK_BASE;
+
+ _int_vec_base_lds = .;
+ .vector : {
+ *(.vector)
+ . = ALIGN(PAGE_SIZE);
+ }
+
+#ifdef CONFIG_ARC_HAS_ICCM
+ .text.arcfp : {
+ *(.text.arcfp)
+ . = ALIGN(CONFIG_ARC_ICCM_SZ * 1024);
+ }
+#endif
+
+ /*
+ * The reason for having a seperate subsection .init.ramfs is to
+ * prevent objump from including it in kernel dumps
+ *
+ * Reason for having .init.ramfs above .init is to make sure that the
+ * binary blob is tucked away to one side, reducing the displacement
+ * between .init.text and .text, avoiding any possible relocation
+ * errors because of calls from .init.text to .text
+ * Yes such calls do exist. e.g.
+ * decompress_inflate.c:gunzip( ) -> zlib_inflate_workspace( )
+ */
+
+ __init_begin = .;
+
+ .init.ramfs : { INIT_RAM_FS }
+
+ . = ALIGN(PAGE_SIZE);
+
+ HEAD_TEXT_SECTION
+ INIT_TEXT_SECTION(L1_CACHE_BYTES)
+
+ /* INIT_DATA_SECTION open-coded: special INIT_RAM_FS handling */
+ .init.data : {
+ INIT_DATA
+ INIT_SETUP(L1_CACHE_BYTES)
+ INIT_CALLS
+ CON_INITCALL
+ }
+
+ .init.arch.info : {
+ __arch_info_begin = .;
+ *(.arch.info.init)
+ __arch_info_end = .;
+ }
+
+ PERCPU_SECTION(L1_CACHE_BYTES)
+
+ . = ALIGN(PAGE_SIZE);
+ __init_end = .;
+
+ .text : {
+ _text = .;
+ _stext = .;
+ TEXT_TEXT
+ SCHED_TEXT
+ LOCK_TEXT
+ KPROBES_TEXT
+ IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
+ *(.fixup)
+ *(.gnu.warning)
+ }
+ EXCEPTION_TABLE(L1_CACHE_BYTES)
+ _etext = .;
+
+ _sdata = .;
+ RO_DATA(PAGE_SIZE)
+
+ /*
+ * 1. this is .data essentially
+ * 2. THREAD_SIZE for init.task, must be kernel-stk sz aligned
+ */
+ RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
+
+ _edata = .;
+
+ BSS_SECTION(4, 4, 4)
+
+#ifdef CONFIG_ARC_DW2_UNWIND
+ . = ALIGN(PAGE_SIZE);
+ .eh_frame : {
+ __start_unwind = .;
+ *(.eh_frame)
+ __end_unwind = .;
+ }
+#else
+ /DISCARD/ : { *(.eh_frame) }
+#endif
+
+ . = ALIGN(PAGE_SIZE);
+ _end = . ;
+
+ STABS_DEBUG
+ ELF_DETAILS
+ DISCARDS
+
+ .arcextmap 0 : {
+ *(.gnu.linkonce.arcextmap.*)
+ *(.arcextmap.*)
+ }
+
+#ifndef CONFIG_DEBUG_INFO
+ /DISCARD/ : { *(.debug_frame) }
+ /DISCARD/ : { *(.debug_aranges) }
+ /DISCARD/ : { *(.debug_pubnames) }
+ /DISCARD/ : { *(.debug_info) }
+ /DISCARD/ : { *(.debug_abbrev) }
+ /DISCARD/ : { *(.debug_line) }
+ /DISCARD/ : { *(.debug_str) }
+ /DISCARD/ : { *(.debug_loc) }
+ /DISCARD/ : { *(.debug_macinfo) }
+ /DISCARD/ : { *(.debug_ranges) }
+#endif
+
+#ifdef CONFIG_ARC_HAS_DCCM
+ . = CONFIG_ARC_DCCM_BASE;
+ __arc_dccm_base = .;
+ .data.arcfp : {
+ *(.data.arcfp)
+ }
+ . = ALIGN(CONFIG_ARC_DCCM_SZ * 1024);
+#endif
+}