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-rw-r--r--arch/openrisc/kernel/.gitignore2
-rw-r--r--arch/openrisc/kernel/Makefile17
-rw-r--r--arch/openrisc/kernel/asm-offsets.c60
-rw-r--r--arch/openrisc/kernel/dma.c125
-rw-r--r--arch/openrisc/kernel/entry.S1244
-rw-r--r--arch/openrisc/kernel/head.S1577
-rw-r--r--arch/openrisc/kernel/irq.c38
-rw-r--r--arch/openrisc/kernel/module.c66
-rw-r--r--arch/openrisc/kernel/or32_ksyms.c46
-rw-r--r--arch/openrisc/kernel/process.c285
-rw-r--r--arch/openrisc/kernel/prom.c27
-rw-r--r--arch/openrisc/kernel/ptrace.c223
-rw-r--r--arch/openrisc/kernel/setup.c377
-rw-r--r--arch/openrisc/kernel/signal.c326
-rw-r--r--arch/openrisc/kernel/smp.c332
-rw-r--r--arch/openrisc/kernel/stacktrace.c100
-rw-r--r--arch/openrisc/kernel/sync-timer.c120
-rw-r--r--arch/openrisc/kernel/sys_call_table.c24
-rw-r--r--arch/openrisc/kernel/time.c179
-rw-r--r--arch/openrisc/kernel/traps.c427
-rw-r--r--arch/openrisc/kernel/unwinder.c105
-rw-r--r--arch/openrisc/kernel/vmlinux.h9
-rw-r--r--arch/openrisc/kernel/vmlinux.lds.S109
23 files changed, 5818 insertions, 0 deletions
diff --git a/arch/openrisc/kernel/.gitignore b/arch/openrisc/kernel/.gitignore
new file mode 100644
index 0000000000..bbb90f92d0
--- /dev/null
+++ b/arch/openrisc/kernel/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vmlinux.lds
diff --git a/arch/openrisc/kernel/Makefile b/arch/openrisc/kernel/Makefile
new file mode 100644
index 0000000000..79129161f3
--- /dev/null
+++ b/arch/openrisc/kernel/Makefile
@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the linux kernel.
+#
+
+extra-y := vmlinux.lds
+
+obj-y := head.o setup.o or32_ksyms.o process.o dma.o \
+ traps.o time.o irq.o entry.o ptrace.o signal.o \
+ sys_call_table.o unwinder.o
+
+obj-$(CONFIG_SMP) += smp.o sync-timer.o
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
+obj-$(CONFIG_MODULES) += module.o
+obj-$(CONFIG_OF) += prom.o
+
+clean:
diff --git a/arch/openrisc/kernel/asm-offsets.c b/arch/openrisc/kernel/asm-offsets.c
new file mode 100644
index 0000000000..710651d5aa
--- /dev/null
+++ b/arch/openrisc/kernel/asm-offsets.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC asm-offsets.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * This program is used to generate definitions needed by
+ * assembly language modules.
+ *
+ * We use the technique used in the OSF Mach kernel code:
+ * generate asm statements containing #defines,
+ * compile this file to assembler, and then extract the
+ * #defines from the assembly-language output.
+ */
+
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+#include <linux/thread_info.h>
+#include <linux/kbuild.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+
+int main(void)
+{
+ /* offsets into the task_struct */
+ DEFINE(TASK_FLAGS, offsetof(struct task_struct, flags));
+ DEFINE(TASK_PTRACE, offsetof(struct task_struct, ptrace));
+ DEFINE(TASK_THREAD, offsetof(struct task_struct, thread));
+ DEFINE(TASK_MM, offsetof(struct task_struct, mm));
+ DEFINE(TASK_ACTIVE_MM, offsetof(struct task_struct, active_mm));
+
+ /* offsets into thread_info */
+ DEFINE(TI_TASK, offsetof(struct thread_info, task));
+ DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
+ DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count));
+ DEFINE(TI_KSP, offsetof(struct thread_info, ksp));
+
+ DEFINE(PT_SIZE, sizeof(struct pt_regs));
+
+ /* Interrupt register frame */
+ DEFINE(STACK_FRAME_OVERHEAD, STACK_FRAME_OVERHEAD);
+ DEFINE(INT_FRAME_SIZE, STACK_FRAME_OVERHEAD + sizeof(struct pt_regs));
+
+ DEFINE(NUM_USER_SEGMENTS, TASK_SIZE >> 28);
+ return 0;
+}
diff --git a/arch/openrisc/kernel/dma.c b/arch/openrisc/kernel/dma.c
new file mode 100644
index 0000000000..b3edbb33b6
--- /dev/null
+++ b/arch/openrisc/kernel/dma.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * DMA mapping callbacks...
+ */
+
+#include <linux/dma-map-ops.h>
+#include <linux/pagewalk.h>
+
+#include <asm/cpuinfo.h>
+#include <asm/spr_defs.h>
+#include <asm/tlbflush.h>
+
+static int
+page_set_nocache(pte_t *pte, unsigned long addr,
+ unsigned long next, struct mm_walk *walk)
+{
+ unsigned long cl;
+ struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
+
+ pte_val(*pte) |= _PAGE_CI;
+
+ /*
+ * Flush the page out of the TLB so that the new page flags get
+ * picked up next time there's an access
+ */
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+
+ /* Flush page out of dcache */
+ for (cl = __pa(addr); cl < __pa(next); cl += cpuinfo->dcache_block_size)
+ mtspr(SPR_DCBFR, cl);
+
+ return 0;
+}
+
+static const struct mm_walk_ops set_nocache_walk_ops = {
+ .pte_entry = page_set_nocache,
+};
+
+static int
+page_clear_nocache(pte_t *pte, unsigned long addr,
+ unsigned long next, struct mm_walk *walk)
+{
+ pte_val(*pte) &= ~_PAGE_CI;
+
+ /*
+ * Flush the page out of the TLB so that the new page flags get
+ * picked up next time there's an access
+ */
+ flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
+
+ return 0;
+}
+
+static const struct mm_walk_ops clear_nocache_walk_ops = {
+ .pte_entry = page_clear_nocache,
+};
+
+void *arch_dma_set_uncached(void *cpu_addr, size_t size)
+{
+ unsigned long va = (unsigned long)cpu_addr;
+ int error;
+
+ /*
+ * We need to iterate through the pages, clearing the dcache for
+ * them and setting the cache-inhibit bit.
+ */
+ mmap_write_lock(&init_mm);
+ error = walk_page_range_novma(&init_mm, va, va + size,
+ &set_nocache_walk_ops, NULL, NULL);
+ mmap_write_unlock(&init_mm);
+
+ if (error)
+ return ERR_PTR(error);
+ return cpu_addr;
+}
+
+void arch_dma_clear_uncached(void *cpu_addr, size_t size)
+{
+ unsigned long va = (unsigned long)cpu_addr;
+
+ mmap_write_lock(&init_mm);
+ /* walk_page_range shouldn't be able to fail here */
+ WARN_ON(walk_page_range_novma(&init_mm, va, va + size,
+ &clear_nocache_walk_ops, NULL, NULL));
+ mmap_write_unlock(&init_mm);
+}
+
+void arch_sync_dma_for_device(phys_addr_t addr, size_t size,
+ enum dma_data_direction dir)
+{
+ unsigned long cl;
+ struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ /* Flush the dcache for the requested range */
+ for (cl = addr; cl < addr + size;
+ cl += cpuinfo->dcache_block_size)
+ mtspr(SPR_DCBFR, cl);
+ break;
+ case DMA_FROM_DEVICE:
+ /* Invalidate the dcache for the requested range */
+ for (cl = addr; cl < addr + size;
+ cl += cpuinfo->dcache_block_size)
+ mtspr(SPR_DCBIR, cl);
+ break;
+ default:
+ /*
+ * NOTE: If dir == DMA_BIDIRECTIONAL then there's no need to
+ * flush nor invalidate the cache here as the area will need
+ * to be manually synced anyway.
+ */
+ break;
+ }
+}
diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
new file mode 100644
index 0000000000..c9f48e750b
--- /dev/null
+++ b/arch/openrisc/kernel/entry.S
@@ -0,0 +1,1244 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * OpenRISC entry.S
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2005 Gyorgy Jeney <nog@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/linkage.h>
+#include <linux/pgtable.h>
+
+#include <asm/processor.h>
+#include <asm/unistd.h>
+#include <asm/thread_info.h>
+#include <asm/errno.h>
+#include <asm/spr_defs.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/asm-offsets.h>
+
+#define DISABLE_INTERRUPTS(t1,t2) \
+ l.mfspr t2,r0,SPR_SR ;\
+ l.movhi t1,hi(~(SPR_SR_IEE|SPR_SR_TEE)) ;\
+ l.ori t1,t1,lo(~(SPR_SR_IEE|SPR_SR_TEE)) ;\
+ l.and t2,t2,t1 ;\
+ l.mtspr r0,t2,SPR_SR
+
+#define ENABLE_INTERRUPTS(t1) \
+ l.mfspr t1,r0,SPR_SR ;\
+ l.ori t1,t1,lo(SPR_SR_IEE|SPR_SR_TEE) ;\
+ l.mtspr r0,t1,SPR_SR
+
+/* =========================================================[ macros ]=== */
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+/*
+ * Trace irq on/off creating a stack frame.
+ */
+#define TRACE_IRQS_OP(trace_op) \
+ l.sw -8(r1),r2 /* store frame pointer */ ;\
+ l.sw -4(r1),r9 /* store return address */ ;\
+ l.addi r2,r1,0 /* move sp to fp */ ;\
+ l.jal trace_op ;\
+ l.addi r1,r1,-8 ;\
+ l.ori r1,r2,0 /* restore sp */ ;\
+ l.lwz r9,-4(r1) /* restore return address */ ;\
+ l.lwz r2,-8(r1) /* restore fp */ ;\
+/*
+ * Trace irq on/off and save registers we need that would otherwise be
+ * clobbered.
+ */
+#define TRACE_IRQS_SAVE(t1,trace_op) \
+ l.sw -12(r1),t1 /* save extra reg */ ;\
+ l.sw -8(r1),r2 /* store frame pointer */ ;\
+ l.sw -4(r1),r9 /* store return address */ ;\
+ l.addi r2,r1,0 /* move sp to fp */ ;\
+ l.jal trace_op ;\
+ l.addi r1,r1,-12 ;\
+ l.ori r1,r2,0 /* restore sp */ ;\
+ l.lwz r9,-4(r1) /* restore return address */ ;\
+ l.lwz r2,-8(r1) /* restore fp */ ;\
+ l.lwz t1,-12(r1) /* restore extra reg */
+
+#define TRACE_IRQS_OFF TRACE_IRQS_OP(trace_hardirqs_off)
+#define TRACE_IRQS_ON TRACE_IRQS_OP(trace_hardirqs_on)
+#define TRACE_IRQS_ON_SYSCALL \
+ TRACE_IRQS_SAVE(r10,trace_hardirqs_on) ;\
+ l.lwz r3,PT_GPR3(r1) ;\
+ l.lwz r4,PT_GPR4(r1) ;\
+ l.lwz r5,PT_GPR5(r1) ;\
+ l.lwz r6,PT_GPR6(r1) ;\
+ l.lwz r7,PT_GPR7(r1) ;\
+ l.lwz r8,PT_GPR8(r1) ;\
+ l.lwz r11,PT_GPR11(r1)
+#define TRACE_IRQS_OFF_ENTRY \
+ l.lwz r5,PT_SR(r1) ;\
+ l.andi r3,r5,(SPR_SR_IEE|SPR_SR_TEE) ;\
+ l.sfeq r5,r0 /* skip trace if irqs were already off */;\
+ l.bf 1f ;\
+ l.nop ;\
+ TRACE_IRQS_SAVE(r4,trace_hardirqs_off) ;\
+1:
+#else
+#define TRACE_IRQS_OFF
+#define TRACE_IRQS_ON
+#define TRACE_IRQS_OFF_ENTRY
+#define TRACE_IRQS_ON_SYSCALL
+#endif
+
+/*
+ * We need to disable interrupts at beginning of RESTORE_ALL
+ * since interrupt might come in after we've loaded EPC return address
+ * and overwrite EPC with address somewhere in RESTORE_ALL
+ * which is of course wrong!
+ */
+
+#define RESTORE_ALL \
+ DISABLE_INTERRUPTS(r3,r4) ;\
+ l.lwz r3,PT_PC(r1) ;\
+ l.mtspr r0,r3,SPR_EPCR_BASE ;\
+ l.lwz r3,PT_SR(r1) ;\
+ l.mtspr r0,r3,SPR_ESR_BASE ;\
+ l.lwz r3,PT_FPCSR(r1) ;\
+ l.mtspr r0,r3,SPR_FPCSR ;\
+ l.lwz r2,PT_GPR2(r1) ;\
+ l.lwz r3,PT_GPR3(r1) ;\
+ l.lwz r4,PT_GPR4(r1) ;\
+ l.lwz r5,PT_GPR5(r1) ;\
+ l.lwz r6,PT_GPR6(r1) ;\
+ l.lwz r7,PT_GPR7(r1) ;\
+ l.lwz r8,PT_GPR8(r1) ;\
+ l.lwz r9,PT_GPR9(r1) ;\
+ l.lwz r10,PT_GPR10(r1) ;\
+ l.lwz r11,PT_GPR11(r1) ;\
+ l.lwz r12,PT_GPR12(r1) ;\
+ l.lwz r13,PT_GPR13(r1) ;\
+ l.lwz r14,PT_GPR14(r1) ;\
+ l.lwz r15,PT_GPR15(r1) ;\
+ l.lwz r16,PT_GPR16(r1) ;\
+ l.lwz r17,PT_GPR17(r1) ;\
+ l.lwz r18,PT_GPR18(r1) ;\
+ l.lwz r19,PT_GPR19(r1) ;\
+ l.lwz r20,PT_GPR20(r1) ;\
+ l.lwz r21,PT_GPR21(r1) ;\
+ l.lwz r22,PT_GPR22(r1) ;\
+ l.lwz r23,PT_GPR23(r1) ;\
+ l.lwz r24,PT_GPR24(r1) ;\
+ l.lwz r25,PT_GPR25(r1) ;\
+ l.lwz r26,PT_GPR26(r1) ;\
+ l.lwz r27,PT_GPR27(r1) ;\
+ l.lwz r28,PT_GPR28(r1) ;\
+ l.lwz r29,PT_GPR29(r1) ;\
+ l.lwz r30,PT_GPR30(r1) ;\
+ l.lwz r31,PT_GPR31(r1) ;\
+ l.lwz r1,PT_SP(r1) ;\
+ l.rfe
+
+
+#define EXCEPTION_ENTRY(handler) \
+ .global handler ;\
+handler: ;\
+ /* r1, EPCR, ESR a already saved */ ;\
+ l.sw PT_GPR2(r1),r2 ;\
+ l.sw PT_GPR3(r1),r3 ;\
+ /* r4 already save */ ;\
+ l.sw PT_GPR5(r1),r5 ;\
+ l.sw PT_GPR6(r1),r6 ;\
+ l.sw PT_GPR7(r1),r7 ;\
+ l.sw PT_GPR8(r1),r8 ;\
+ l.sw PT_GPR9(r1),r9 ;\
+ /* r10 already saved */ ;\
+ l.sw PT_GPR11(r1),r11 ;\
+ /* r12 already saved */ ;\
+ l.sw PT_GPR13(r1),r13 ;\
+ l.sw PT_GPR14(r1),r14 ;\
+ l.sw PT_GPR15(r1),r15 ;\
+ l.sw PT_GPR16(r1),r16 ;\
+ l.sw PT_GPR17(r1),r17 ;\
+ l.sw PT_GPR18(r1),r18 ;\
+ l.sw PT_GPR19(r1),r19 ;\
+ l.sw PT_GPR20(r1),r20 ;\
+ l.sw PT_GPR21(r1),r21 ;\
+ l.sw PT_GPR22(r1),r22 ;\
+ l.sw PT_GPR23(r1),r23 ;\
+ l.sw PT_GPR24(r1),r24 ;\
+ l.sw PT_GPR25(r1),r25 ;\
+ l.sw PT_GPR26(r1),r26 ;\
+ l.sw PT_GPR27(r1),r27 ;\
+ l.sw PT_GPR28(r1),r28 ;\
+ l.sw PT_GPR29(r1),r29 ;\
+ /* r30 already save */ ;\
+ l.sw PT_GPR31(r1),r31 ;\
+ TRACE_IRQS_OFF_ENTRY ;\
+ l.mfspr r30,r0,SPR_FPCSR ;\
+ l.sw PT_FPCSR(r1),r30 ;\
+ /* Store -1 in orig_gpr11 for non-syscall exceptions */ ;\
+ l.addi r30,r0,-1 ;\
+ l.sw PT_ORIG_GPR11(r1),r30
+
+#define UNHANDLED_EXCEPTION(handler,vector) \
+ .global handler ;\
+handler: ;\
+ /* r1, EPCR, ESR already saved */ ;\
+ l.sw PT_GPR2(r1),r2 ;\
+ l.sw PT_GPR3(r1),r3 ;\
+ l.sw PT_GPR5(r1),r5 ;\
+ l.sw PT_GPR6(r1),r6 ;\
+ l.sw PT_GPR7(r1),r7 ;\
+ l.sw PT_GPR8(r1),r8 ;\
+ l.sw PT_GPR9(r1),r9 ;\
+ /* r10 already saved */ ;\
+ l.sw PT_GPR11(r1),r11 ;\
+ /* r12 already saved */ ;\
+ l.sw PT_GPR13(r1),r13 ;\
+ l.sw PT_GPR14(r1),r14 ;\
+ l.sw PT_GPR15(r1),r15 ;\
+ l.sw PT_GPR16(r1),r16 ;\
+ l.sw PT_GPR17(r1),r17 ;\
+ l.sw PT_GPR18(r1),r18 ;\
+ l.sw PT_GPR19(r1),r19 ;\
+ l.sw PT_GPR20(r1),r20 ;\
+ l.sw PT_GPR21(r1),r21 ;\
+ l.sw PT_GPR22(r1),r22 ;\
+ l.sw PT_GPR23(r1),r23 ;\
+ l.sw PT_GPR24(r1),r24 ;\
+ l.sw PT_GPR25(r1),r25 ;\
+ l.sw PT_GPR26(r1),r26 ;\
+ l.sw PT_GPR27(r1),r27 ;\
+ l.sw PT_GPR28(r1),r28 ;\
+ l.sw PT_GPR29(r1),r29 ;\
+ /* r30 already saved */ ;\
+ l.sw PT_GPR31(r1),r31 ;\
+ /* Store -1 in orig_gpr11 for non-syscall exceptions */ ;\
+ l.addi r30,r0,-1 ;\
+ l.sw PT_ORIG_GPR11(r1),r30 ;\
+ l.mfspr r30,r0,SPR_FPCSR ;\
+ l.sw PT_FPCSR(r1),r30 ;\
+ l.addi r3,r1,0 ;\
+ /* r4 is exception EA */ ;\
+ l.addi r5,r0,vector ;\
+ l.jal unhandled_exception ;\
+ l.nop ;\
+ l.j _ret_from_exception ;\
+ l.nop
+
+/* clobbers 'reg' */
+#define CLEAR_LWA_FLAG(reg) \
+ l.movhi reg,hi(lwa_flag) ;\
+ l.ori reg,reg,lo(lwa_flag) ;\
+ l.sw 0(reg),r0
+/*
+ * NOTE: one should never assume that SPR_EPC, SPR_ESR, SPR_EEAR
+ * contain the same values as when exception we're handling
+ * occured. in fact they never do. if you need them use
+ * values saved on stack (for SPR_EPC, SPR_ESR) or content
+ * of r4 (for SPR_EEAR). for details look at EXCEPTION_HANDLE()
+ * in 'arch/openrisc/kernel/head.S'
+ */
+
+/* =====================================================[ exceptions] === */
+
+/* ---[ 0x100: RESET exception ]----------------------------------------- */
+
+EXCEPTION_ENTRY(_tng_kernel_start)
+ l.jal _start
+ l.andi r0,r0,0
+
+/* ---[ 0x200: BUS exception ]------------------------------------------- */
+
+EXCEPTION_ENTRY(_bus_fault_handler)
+ CLEAR_LWA_FLAG(r3)
+ /* r4: EA of fault (set by EXCEPTION_HANDLE) */
+ l.jal do_bus_fault
+ l.addi r3,r1,0 /* pt_regs */
+
+ l.j _ret_from_exception
+ l.nop
+
+/* ---[ 0x300: Data Page Fault exception ]------------------------------- */
+EXCEPTION_ENTRY(_dtlb_miss_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
+ l.and r5,r5,r0
+ l.j 1f
+ l.nop
+
+EXCEPTION_ENTRY(_data_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
+ /* set up parameters for do_page_fault */
+ l.ori r5,r0,0x300 // exception vector
+1:
+ l.addi r3,r1,0 // pt_regs
+ /* r4 set be EXCEPTION_HANDLE */ // effective address of fault
+
+#ifdef CONFIG_OPENRISC_NO_SPR_SR_DSX
+ l.lwz r6,PT_PC(r3) // address of an offending insn
+ l.lwz r6,0(r6) // instruction that caused pf
+
+ l.srli r6,r6,26 // check opcode for jump insn
+ l.sfeqi r6,0 // l.j
+ l.bf 8f
+ l.sfeqi r6,1 // l.jal
+ l.bf 8f
+ l.sfeqi r6,3 // l.bnf
+ l.bf 8f
+ l.sfeqi r6,4 // l.bf
+ l.bf 8f
+ l.sfeqi r6,0x11 // l.jr
+ l.bf 8f
+ l.sfeqi r6,0x12 // l.jalr
+ l.bf 8f
+ l.nop
+
+ l.j 9f
+ l.nop
+
+8: // offending insn is in delay slot
+ l.lwz r6,PT_PC(r3) // address of an offending insn
+ l.addi r6,r6,4
+ l.lwz r6,0(r6) // instruction that caused pf
+ l.srli r6,r6,26 // get opcode
+9: // offending instruction opcode loaded in r6
+
+#else
+
+ l.mfspr r6,r0,SPR_SR // SR
+ l.andi r6,r6,SPR_SR_DSX // check for delay slot exception
+ l.sfne r6,r0 // exception happened in delay slot
+ l.bnf 7f
+ l.lwz r6,PT_PC(r3) // address of an offending insn
+
+ l.addi r6,r6,4 // offending insn is in delay slot
+7:
+ l.lwz r6,0(r6) // instruction that caused pf
+ l.srli r6,r6,26 // check opcode for write access
+#endif
+
+ l.sfgeui r6,0x33 // check opcode for write access
+ l.bnf 1f
+ l.sfleui r6,0x37
+ l.bnf 1f
+ l.ori r6,r0,0x1 // write access
+ l.j 2f
+ l.nop
+1: l.ori r6,r0,0x0 // !write access
+2:
+
+ /* call fault.c handler in openrisc/mm/fault.c */
+ l.jal do_page_fault
+ l.nop
+ l.j _ret_from_exception
+ l.nop
+
+/* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
+EXCEPTION_ENTRY(_itlb_miss_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
+ l.and r5,r5,r0
+ l.j 1f
+ l.nop
+
+EXCEPTION_ENTRY(_insn_page_fault_handler)
+ CLEAR_LWA_FLAG(r3)
+ /* set up parameters for do_page_fault */
+ l.ori r5,r0,0x400 // exception vector
+1:
+ l.addi r3,r1,0 // pt_regs
+ /* r4 set be EXCEPTION_HANDLE */ // effective address of fault
+ l.ori r6,r0,0x0 // !write access
+
+ /* call fault.c handler in openrisc/mm/fault.c */
+ l.jal do_page_fault
+ l.nop
+ l.j _ret_from_exception
+ l.nop
+
+
+/* ---[ 0x500: Timer exception ]----------------------------------------- */
+
+EXCEPTION_ENTRY(_timer_handler)
+ CLEAR_LWA_FLAG(r3)
+ l.jal timer_interrupt
+ l.addi r3,r1,0 /* pt_regs */
+
+ l.j _ret_from_intr
+ l.nop
+
+/* ---[ 0x600: Alignment exception ]-------------------------------------- */
+
+EXCEPTION_ENTRY(_alignment_handler)
+ CLEAR_LWA_FLAG(r3)
+ /* r4: EA of fault (set by EXCEPTION_HANDLE) */
+ l.jal do_unaligned_access
+ l.addi r3,r1,0 /* pt_regs */
+
+ l.j _ret_from_exception
+ l.nop
+
+#if 0
+EXCEPTION_ENTRY(_alignment_handler)
+// l.mfspr r2,r0,SPR_EEAR_BASE /* Load the effective address */
+ l.addi r2,r4,0
+// l.mfspr r5,r0,SPR_EPCR_BASE /* Load the insn address */
+ l.lwz r5,PT_PC(r1)
+
+ l.lwz r3,0(r5) /* Load insn */
+ l.srli r4,r3,26 /* Shift left to get the insn opcode */
+
+ l.sfeqi r4,0x00 /* Check if the load/store insn is in delay slot */
+ l.bf jmp
+ l.sfeqi r4,0x01
+ l.bf jmp
+ l.sfeqi r4,0x03
+ l.bf jmp
+ l.sfeqi r4,0x04
+ l.bf jmp
+ l.sfeqi r4,0x11
+ l.bf jr
+ l.sfeqi r4,0x12
+ l.bf jr
+ l.nop
+ l.j 1f
+ l.addi r5,r5,4 /* Increment PC to get return insn address */
+
+jmp:
+ l.slli r4,r3,6 /* Get the signed extended jump length */
+ l.srai r4,r4,4
+
+ l.lwz r3,4(r5) /* Load the real load/store insn */
+
+ l.add r5,r5,r4 /* Calculate jump target address */
+
+ l.j 1f
+ l.srli r4,r3,26 /* Shift left to get the insn opcode */
+
+jr:
+ l.slli r4,r3,9 /* Shift to get the reg nb */
+ l.andi r4,r4,0x7c
+
+ l.lwz r3,4(r5) /* Load the real load/store insn */
+
+ l.add r4,r4,r1 /* Load the jump register value from the stack */
+ l.lwz r5,0(r4)
+
+ l.srli r4,r3,26 /* Shift left to get the insn opcode */
+
+
+1:
+// l.mtspr r0,r5,SPR_EPCR_BASE
+ l.sw PT_PC(r1),r5
+
+ l.sfeqi r4,0x26
+ l.bf lhs
+ l.sfeqi r4,0x25
+ l.bf lhz
+ l.sfeqi r4,0x22
+ l.bf lws
+ l.sfeqi r4,0x21
+ l.bf lwz
+ l.sfeqi r4,0x37
+ l.bf sh
+ l.sfeqi r4,0x35
+ l.bf sw
+ l.nop
+
+1: l.j 1b /* I don't know what to do */
+ l.nop
+
+lhs: l.lbs r5,0(r2)
+ l.slli r5,r5,8
+ l.lbz r6,1(r2)
+ l.or r5,r5,r6
+ l.srli r4,r3,19
+ l.andi r4,r4,0x7c
+ l.add r4,r4,r1
+ l.j align_end
+ l.sw 0(r4),r5
+
+lhz: l.lbz r5,0(r2)
+ l.slli r5,r5,8
+ l.lbz r6,1(r2)
+ l.or r5,r5,r6
+ l.srli r4,r3,19
+ l.andi r4,r4,0x7c
+ l.add r4,r4,r1
+ l.j align_end
+ l.sw 0(r4),r5
+
+lws: l.lbs r5,0(r2)
+ l.slli r5,r5,24
+ l.lbz r6,1(r2)
+ l.slli r6,r6,16
+ l.or r5,r5,r6
+ l.lbz r6,2(r2)
+ l.slli r6,r6,8
+ l.or r5,r5,r6
+ l.lbz r6,3(r2)
+ l.or r5,r5,r6
+ l.srli r4,r3,19
+ l.andi r4,r4,0x7c
+ l.add r4,r4,r1
+ l.j align_end
+ l.sw 0(r4),r5
+
+lwz: l.lbz r5,0(r2)
+ l.slli r5,r5,24
+ l.lbz r6,1(r2)
+ l.slli r6,r6,16
+ l.or r5,r5,r6
+ l.lbz r6,2(r2)
+ l.slli r6,r6,8
+ l.or r5,r5,r6
+ l.lbz r6,3(r2)
+ l.or r5,r5,r6
+ l.srli r4,r3,19
+ l.andi r4,r4,0x7c
+ l.add r4,r4,r1
+ l.j align_end
+ l.sw 0(r4),r5
+
+sh:
+ l.srli r4,r3,9
+ l.andi r4,r4,0x7c
+ l.add r4,r4,r1
+ l.lwz r5,0(r4)
+ l.sb 1(r2),r5
+ l.srli r5,r5,8
+ l.j align_end
+ l.sb 0(r2),r5
+
+sw:
+ l.srli r4,r3,9
+ l.andi r4,r4,0x7c
+ l.add r4,r4,r1
+ l.lwz r5,0(r4)
+ l.sb 3(r2),r5
+ l.srli r5,r5,8
+ l.sb 2(r2),r5
+ l.srli r5,r5,8
+ l.sb 1(r2),r5
+ l.srli r5,r5,8
+ l.j align_end
+ l.sb 0(r2),r5
+
+align_end:
+ l.j _ret_from_intr
+ l.nop
+#endif
+
+/* ---[ 0x700: Illegal insn exception ]---------------------------------- */
+
+EXCEPTION_ENTRY(_illegal_instruction_handler)
+ /* r4: EA of fault (set by EXCEPTION_HANDLE) */
+ l.jal do_illegal_instruction
+ l.addi r3,r1,0 /* pt_regs */
+
+ l.j _ret_from_exception
+ l.nop
+
+/* ---[ 0x800: External interrupt exception ]---------------------------- */
+
+EXCEPTION_ENTRY(_external_irq_handler)
+#ifdef CONFIG_OPENRISC_ESR_EXCEPTION_BUG_CHECK
+ l.lwz r4,PT_SR(r1) // were interrupts enabled ?
+ l.andi r4,r4,SPR_SR_IEE
+ l.sfeqi r4,0
+ l.bnf 1f // ext irq enabled, all ok.
+ l.nop
+
+#ifdef CONFIG_PRINTK
+ l.addi r1,r1,-0x8
+ l.movhi r3,hi(42f)
+ l.ori r3,r3,lo(42f)
+ l.sw 0x0(r1),r3
+ l.jal _printk
+ l.sw 0x4(r1),r4
+ l.addi r1,r1,0x8
+
+ .section .rodata, "a"
+42:
+ .string "\n\rESR interrupt bug: in _external_irq_handler (ESR %x)\n\r"
+ .align 4
+ .previous
+#endif
+
+ l.ori r4,r4,SPR_SR_IEE // fix the bug
+// l.sw PT_SR(r1),r4
+1:
+#endif
+ CLEAR_LWA_FLAG(r3)
+ l.addi r3,r1,0
+ l.movhi r8,hi(generic_handle_arch_irq)
+ l.ori r8,r8,lo(generic_handle_arch_irq)
+ l.jalr r8
+ l.nop
+ l.j _ret_from_intr
+ l.nop
+
+/* ---[ 0x900: DTLB miss exception ]------------------------------------- */
+
+
+/* ---[ 0xa00: ITLB miss exception ]------------------------------------- */
+
+
+/* ---[ 0xb00: Range exception ]----------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0xb00,0xb00)
+
+/* ---[ 0xc00: Syscall exception ]--------------------------------------- */
+
+/*
+ * Syscalls are a special type of exception in that they are
+ * _explicitly_ invoked by userspace and can therefore be
+ * held to conform to the same ABI as normal functions with
+ * respect to whether registers are preserved across the call
+ * or not.
+ */
+
+/* Upon syscall entry we just save the callee-saved registers
+ * and not the call-clobbered ones.
+ */
+
+_string_syscall_return:
+ .string "syscall r9:0x%08x -> syscall(%ld) return %ld\0"
+ .align 4
+
+ENTRY(_sys_call_handler)
+ /* r1, EPCR, ESR a already saved */
+ l.sw PT_GPR2(r1),r2
+ /* r3-r8 must be saved because syscall restart relies
+ * on us being able to restart the syscall args... technically
+ * they should be clobbered, otherwise
+ */
+ l.sw PT_GPR3(r1),r3
+ /*
+ * r4 already saved
+ * r4 holds the EEAR address of the fault, use it as screatch reg and
+ * then load the original r4
+ */
+ CLEAR_LWA_FLAG(r4)
+ l.lwz r4,PT_GPR4(r1)
+ l.sw PT_GPR5(r1),r5
+ l.sw PT_GPR6(r1),r6
+ l.sw PT_GPR7(r1),r7
+ l.sw PT_GPR8(r1),r8
+ l.sw PT_GPR9(r1),r9
+ /* r10 already saved */
+ l.sw PT_GPR11(r1),r11
+ /* orig_gpr11 must be set for syscalls */
+ l.sw PT_ORIG_GPR11(r1),r11
+ /* r12,r13 already saved */
+
+ /* r14-r28 (even) aren't touched by the syscall fast path below
+ * so we don't need to save them. However, the functions that return
+ * to userspace via a call to switch() DO need to save these because
+ * switch() effectively clobbers them... saving these registers for
+ * such functions is handled in their syscall wrappers (see fork, vfork,
+ * and clone, below).
+
+ /* r30 is the only register we clobber in the fast path */
+ /* r30 already saved */
+/* l.sw PT_GPR30(r1),r30 */
+
+_syscall_check_trace_enter:
+ /* syscalls run with interrupts enabled */
+ TRACE_IRQS_ON_SYSCALL
+ ENABLE_INTERRUPTS(r29) // enable interrupts, r29 is temp
+
+ /* If TIF_SYSCALL_TRACE is set, then we want to do syscall tracing */
+ l.lwz r30,TI_FLAGS(r10)
+ l.andi r30,r30,_TIF_SYSCALL_TRACE
+ l.sfne r30,r0
+ l.bf _syscall_trace_enter
+ l.nop
+
+_syscall_check:
+ /* Ensure that the syscall number is reasonable */
+ l.sfgeui r11,__NR_syscalls
+ l.bf _syscall_badsys
+ l.nop
+
+_syscall_call:
+ l.movhi r29,hi(sys_call_table)
+ l.ori r29,r29,lo(sys_call_table)
+ l.slli r11,r11,2
+ l.add r29,r29,r11
+ l.lwz r29,0(r29)
+
+ l.jalr r29
+ l.nop
+
+_syscall_return:
+ /* All syscalls return here... just pay attention to ret_from_fork
+ * which does it in a round-about way.
+ */
+ l.sw PT_GPR11(r1),r11 // save return value
+
+#if 0
+_syscall_debug:
+ l.movhi r3,hi(_string_syscall_return)
+ l.ori r3,r3,lo(_string_syscall_return)
+ l.ori r27,r0,2
+ l.sw -4(r1),r27
+ l.sw -8(r1),r11
+ l.lwz r29,PT_ORIG_GPR11(r1)
+ l.sw -12(r1),r29
+ l.lwz r29,PT_GPR9(r1)
+ l.sw -16(r1),r29
+ l.movhi r27,hi(_printk)
+ l.ori r27,r27,lo(_printk)
+ l.jalr r27
+ l.addi r1,r1,-16
+ l.addi r1,r1,16
+#endif
+#if 0
+_syscall_show_regs:
+ l.movhi r27,hi(show_registers)
+ l.ori r27,r27,lo(show_registers)
+ l.jalr r27
+ l.or r3,r1,r1
+#endif
+
+_syscall_check_trace_leave:
+ /* r30 is a callee-saved register so this should still hold the
+ * _TIF_SYSCALL_TRACE flag from _syscall_check_trace_enter above...
+ * _syscall_trace_leave expects syscall result to be in pt_regs->r11.
+ */
+ l.sfne r30,r0
+ l.bf _syscall_trace_leave
+ l.nop
+
+/* This is where the exception-return code begins... interrupts need to be
+ * disabled the rest of the way here because we can't afford to miss any
+ * interrupts that set NEED_RESCHED or SIGNALPENDING... really true? */
+
+_syscall_check_work:
+ /* Here we need to disable interrupts */
+ DISABLE_INTERRUPTS(r27,r29)
+ TRACE_IRQS_OFF
+ l.lwz r30,TI_FLAGS(r10)
+ l.andi r30,r30,_TIF_WORK_MASK
+ l.sfne r30,r0
+
+ l.bnf _syscall_resume_userspace
+ l.nop
+
+ /* Work pending follows a different return path, so we need to
+ * make sure that all the call-saved registers get into pt_regs
+ * before branching...
+ */
+ l.sw PT_GPR14(r1),r14
+ l.sw PT_GPR16(r1),r16
+ l.sw PT_GPR18(r1),r18
+ l.sw PT_GPR20(r1),r20
+ l.sw PT_GPR22(r1),r22
+ l.sw PT_GPR24(r1),r24
+ l.sw PT_GPR26(r1),r26
+ l.sw PT_GPR28(r1),r28
+
+ /* _work_pending needs to be called with interrupts disabled */
+ l.j _work_pending
+ l.nop
+
+_syscall_resume_userspace:
+// ENABLE_INTERRUPTS(r29)
+
+
+/* This is the hot path for returning to userspace from a syscall. If there's
+ * work to be done and the branch to _work_pending was taken above, then the
+ * return to userspace will be done via the normal exception return path...
+ * that path restores _all_ registers and will overwrite the "clobbered"
+ * registers with whatever garbage is in pt_regs -- that's OK because those
+ * registers are clobbered anyway and because the extra work is insignificant
+ * in the context of the extra work that _work_pending is doing.
+
+/* Once again, syscalls are special and only guarantee to preserve the
+ * same registers as a normal function call */
+
+/* The assumption here is that the registers r14-r28 (even) are untouched and
+ * don't need to be restored... be sure that that's really the case!
+ */
+
+/* This is still too much... we should only be restoring what we actually
+ * clobbered... we should even be using 'scratch' (odd) regs above so that
+ * we don't need to restore anything, hardly...
+ */
+
+ l.lwz r2,PT_GPR2(r1)
+
+ /* Restore args */
+ /* r3-r8 are technically clobbered, but syscall restart needs these
+ * to be restored...
+ */
+ l.lwz r3,PT_GPR3(r1)
+ l.lwz r4,PT_GPR4(r1)
+ l.lwz r5,PT_GPR5(r1)
+ l.lwz r6,PT_GPR6(r1)
+ l.lwz r7,PT_GPR7(r1)
+ l.lwz r8,PT_GPR8(r1)
+
+ l.lwz r9,PT_GPR9(r1)
+ l.lwz r10,PT_GPR10(r1)
+ l.lwz r11,PT_GPR11(r1)
+
+ /* r30 is the only register we clobber in the fast path */
+ l.lwz r30,PT_GPR30(r1)
+
+ /* Here we use r13-r19 (odd) as scratch regs */
+ l.lwz r13,PT_PC(r1)
+ l.lwz r15,PT_SR(r1)
+ l.lwz r1,PT_SP(r1)
+ /* Interrupts need to be disabled for setting EPCR and ESR
+ * so that another interrupt doesn't come in here and clobber
+ * them before we can use them for our l.rfe */
+ DISABLE_INTERRUPTS(r17,r19)
+ l.mtspr r0,r13,SPR_EPCR_BASE
+ l.mtspr r0,r15,SPR_ESR_BASE
+ l.rfe
+
+/* End of hot path!
+ * Keep the below tracing and error handling out of the hot path...
+*/
+
+_syscall_trace_enter:
+ /* Here we pass pt_regs to do_syscall_trace_enter. Make sure
+ * that function is really getting all the info it needs as
+ * pt_regs isn't a complete set of userspace regs, just the
+ * ones relevant to the syscall...
+ *
+ * Note use of delay slot for setting argument.
+ */
+ l.jal do_syscall_trace_enter
+ l.addi r3,r1,0
+
+ /* Restore arguments (not preserved across do_syscall_trace_enter)
+ * so that we can do the syscall for real and return to the syscall
+ * hot path.
+ */
+ l.lwz r11,PT_GPR11(r1)
+ l.lwz r3,PT_GPR3(r1)
+ l.lwz r4,PT_GPR4(r1)
+ l.lwz r5,PT_GPR5(r1)
+ l.lwz r6,PT_GPR6(r1)
+ l.lwz r7,PT_GPR7(r1)
+
+ l.j _syscall_check
+ l.lwz r8,PT_GPR8(r1)
+
+_syscall_trace_leave:
+ l.jal do_syscall_trace_leave
+ l.addi r3,r1,0
+
+ l.j _syscall_check_work
+ l.nop
+
+_syscall_badsys:
+ /* Here we effectively pretend to have executed an imaginary
+ * syscall that returns -ENOSYS and then return to the regular
+ * syscall hot path.
+ * Note that "return value" is set in the delay slot...
+ */
+ l.j _syscall_return
+ l.addi r11,r0,-ENOSYS
+
+/******* END SYSCALL HANDLING *******/
+
+/* ---[ 0xd00: Floating Point exception ]-------------------------------- */
+
+EXCEPTION_ENTRY(_fpe_trap_handler)
+ CLEAR_LWA_FLAG(r3)
+ /* r4: EA of fault (set by EXCEPTION_HANDLE) */
+ l.jal do_fpe_trap
+ l.addi r3,r1,0 /* pt_regs */
+
+ l.j _ret_from_exception
+ l.nop
+
+/* ---[ 0xe00: Trap exception ]------------------------------------------ */
+
+EXCEPTION_ENTRY(_trap_handler)
+ CLEAR_LWA_FLAG(r3)
+ /* r4: EA of fault (set by EXCEPTION_HANDLE) */
+ l.jal do_trap
+ l.addi r3,r1,0 /* pt_regs */
+
+ l.j _ret_from_exception
+ l.nop
+
+/* ---[ 0xf00: Reserved exception ]-------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0xf00,0xf00)
+
+/* ---[ 0x1000: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1000,0x1000)
+
+/* ---[ 0x1100: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1100,0x1100)
+
+/* ---[ 0x1200: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1200,0x1200)
+
+/* ---[ 0x1300: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1300,0x1300)
+
+/* ---[ 0x1400: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1400,0x1400)
+
+/* ---[ 0x1500: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1500,0x1500)
+
+/* ---[ 0x1600: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1600,0x1600)
+
+/* ---[ 0x1700: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1700,0x1700)
+
+/* ---[ 0x1800: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1800,0x1800)
+
+/* ---[ 0x1900: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1900,0x1900)
+
+/* ---[ 0x1a00: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1a00,0x1a00)
+
+/* ---[ 0x1b00: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1b00,0x1b00)
+
+/* ---[ 0x1c00: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1c00,0x1c00)
+
+/* ---[ 0x1d00: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1d00,0x1d00)
+
+/* ---[ 0x1e00: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1e00,0x1e00)
+
+/* ---[ 0x1f00: Reserved exception ]------------------------------------- */
+
+UNHANDLED_EXCEPTION(_vector_0x1f00,0x1f00)
+
+/* ========================================================[ return ] === */
+
+_resume_userspace:
+ DISABLE_INTERRUPTS(r3,r4)
+ TRACE_IRQS_OFF
+ l.lwz r4,TI_FLAGS(r10)
+ l.andi r13,r4,_TIF_WORK_MASK
+ l.sfeqi r13,0
+ l.bf _restore_all
+ l.nop
+
+_work_pending:
+ l.lwz r5,PT_ORIG_GPR11(r1)
+ l.sfltsi r5,0
+ l.bnf 1f
+ l.nop
+ l.andi r5,r5,0
+1:
+ l.jal do_work_pending
+ l.ori r3,r1,0 /* pt_regs */
+
+ l.sfeqi r11,0
+ l.bf _restore_all
+ l.nop
+ l.sfltsi r11,0
+ l.bnf 1f
+ l.nop
+ l.and r11,r11,r0
+ l.ori r11,r11,__NR_restart_syscall
+ l.j _syscall_check_trace_enter
+ l.nop
+1:
+ l.lwz r11,PT_ORIG_GPR11(r1)
+ /* Restore arg registers */
+ l.lwz r3,PT_GPR3(r1)
+ l.lwz r4,PT_GPR4(r1)
+ l.lwz r5,PT_GPR5(r1)
+ l.lwz r6,PT_GPR6(r1)
+ l.lwz r7,PT_GPR7(r1)
+ l.j _syscall_check_trace_enter
+ l.lwz r8,PT_GPR8(r1)
+
+_restore_all:
+#ifdef CONFIG_TRACE_IRQFLAGS
+ l.lwz r4,PT_SR(r1)
+ l.andi r3,r4,(SPR_SR_IEE|SPR_SR_TEE)
+ l.sfeq r3,r0 /* skip trace if irqs were off */
+ l.bf skip_hardirqs_on
+ l.nop
+ TRACE_IRQS_ON
+skip_hardirqs_on:
+#endif
+ RESTORE_ALL
+ /* This returns to userspace code */
+
+
+ENTRY(_ret_from_intr)
+ENTRY(_ret_from_exception)
+ l.lwz r4,PT_SR(r1)
+ l.andi r3,r4,SPR_SR_SM
+ l.sfeqi r3,0
+ l.bnf _restore_all
+ l.nop
+ l.j _resume_userspace
+ l.nop
+
+ENTRY(ret_from_fork)
+ l.jal schedule_tail
+ l.nop
+
+ /* Check if we are a kernel thread */
+ l.sfeqi r20,0
+ l.bf 1f
+ l.nop
+
+ /* ...we are a kernel thread so invoke the requested callback */
+ l.jalr r20
+ l.or r3,r22,r0
+
+1:
+ /* _syscall_returns expect r11 to contain return value */
+ l.lwz r11,PT_GPR11(r1)
+
+ /* The syscall fast path return expects call-saved registers
+ * r14-r28 to be untouched, so we restore them here as they
+ * will have been effectively clobbered when arriving here
+ * via the call to switch()
+ */
+ l.lwz r14,PT_GPR14(r1)
+ l.lwz r16,PT_GPR16(r1)
+ l.lwz r18,PT_GPR18(r1)
+ l.lwz r20,PT_GPR20(r1)
+ l.lwz r22,PT_GPR22(r1)
+ l.lwz r24,PT_GPR24(r1)
+ l.lwz r26,PT_GPR26(r1)
+ l.lwz r28,PT_GPR28(r1)
+
+ l.j _syscall_return
+ l.nop
+
+/* ========================================================[ switch ] === */
+
+/*
+ * This routine switches between two different tasks. The process
+ * state of one is saved on its kernel stack. Then the state
+ * of the other is restored from its kernel stack. The memory
+ * management hardware is updated to the second process's state.
+ * Finally, we can return to the second process, via the 'return'.
+ *
+ * Note: there are two ways to get to the "going out" portion
+ * of this code; either by coming in via the entry (_switch)
+ * or via "fork" which must set up an environment equivalent
+ * to the "_switch" path. If you change this (or in particular, the
+ * SAVE_REGS macro), you'll have to change the fork code also.
+ */
+
+
+/* _switch MUST never lay on page boundry, cause it runs from
+ * effective addresses and beeing interrupted by iTLB miss would kill it.
+ * dTLB miss seems to never accour in the bad place since data accesses
+ * are from task structures which are always page aligned.
+ *
+ * The problem happens in RESTORE_ALL where we first set the EPCR
+ * register, then load the previous register values and only at the end call
+ * the l.rfe instruction. If get TLB miss in beetwen the EPCR register gets
+ * garbled and we end up calling l.rfe with the wrong EPCR. (same probably
+ * holds for ESR)
+ *
+ * To avoid this problems it is sufficient to align _switch to
+ * some nice round number smaller than it's size...
+ */
+
+/* ABI rules apply here... we either enter _switch via schedule() or via
+ * an imaginary call to which we shall return at return_from_fork. Either
+ * way, we are a function call and only need to preserve the callee-saved
+ * registers when we return. As such, we don't need to save the registers
+ * on the stack that we won't be returning as they were...
+ */
+
+ .align 0x400
+ENTRY(_switch)
+ /* We don't store SR as _switch only gets called in a context where
+ * the SR will be the same going in and coming out... */
+
+ /* Set up new pt_regs struct for saving task state */
+ l.addi r1,r1,-(INT_FRAME_SIZE)
+
+ /* No need to store r1/PT_SP as it goes into KSP below */
+ l.sw PT_GPR2(r1),r2
+ l.sw PT_GPR9(r1),r9
+
+ /* Save callee-saved registers to the new pt_regs */
+ l.sw PT_GPR14(r1),r14
+ l.sw PT_GPR16(r1),r16
+ l.sw PT_GPR18(r1),r18
+ l.sw PT_GPR20(r1),r20
+ l.sw PT_GPR22(r1),r22
+ l.sw PT_GPR24(r1),r24
+ l.sw PT_GPR26(r1),r26
+ l.sw PT_GPR28(r1),r28
+ l.sw PT_GPR30(r1),r30
+
+ /* Store the old FPU state to new pt_regs */
+ l.mfspr r29,r0,SPR_FPCSR
+ l.sw PT_FPCSR(r1),r29
+
+ l.addi r11,r10,0 /* Save old 'current' to 'last' return value*/
+
+ /* We use thread_info->ksp for storing the address of the above
+ * structure so that we can get back to it later... we don't want
+ * to lose the value of thread_info->ksp, though, so store it as
+ * pt_regs->sp so that we can easily restore it when we are made
+ * live again...
+ */
+
+ /* Save the old value of thread_info->ksp as pt_regs->sp */
+ l.lwz r29,TI_KSP(r10)
+ l.sw PT_SP(r1),r29
+
+ /* Swap kernel stack pointers */
+ l.sw TI_KSP(r10),r1 /* Save old stack pointer */
+ l.or r10,r4,r0 /* Set up new current_thread_info */
+ l.lwz r1,TI_KSP(r10) /* Load new stack pointer */
+
+ /* Restore the old value of thread_info->ksp */
+ l.lwz r29,PT_SP(r1)
+ l.sw TI_KSP(r10),r29
+
+ /* Restore the old value of FPCSR */
+ l.lwz r29,PT_FPCSR(r1)
+ l.mtspr r0,r29,SPR_FPCSR
+
+ /* ...and restore the registers, except r11 because the return value
+ * has already been set above.
+ */
+ l.lwz r2,PT_GPR2(r1)
+ l.lwz r9,PT_GPR9(r1)
+ /* No need to restore r10 */
+ /* ...and do not restore r11 */
+
+ /* Restore callee-saved registers */
+ l.lwz r14,PT_GPR14(r1)
+ l.lwz r16,PT_GPR16(r1)
+ l.lwz r18,PT_GPR18(r1)
+ l.lwz r20,PT_GPR20(r1)
+ l.lwz r22,PT_GPR22(r1)
+ l.lwz r24,PT_GPR24(r1)
+ l.lwz r26,PT_GPR26(r1)
+ l.lwz r28,PT_GPR28(r1)
+ l.lwz r30,PT_GPR30(r1)
+
+ /* Unwind stack to pre-switch state */
+ l.addi r1,r1,(INT_FRAME_SIZE)
+
+ /* Return via the link-register back to where we 'came from', where
+ * that may be either schedule(), ret_from_fork(), or
+ * ret_from_kernel_thread(). If we are returning to a new thread,
+ * we are expected to have set up the arg to schedule_tail already,
+ * hence we do so here unconditionally:
+ */
+ l.lwz r3,TI_TASK(r3) /* Load 'prev' as schedule_tail arg */
+ l.jr r9
+ l.nop
+
+/* ==================================================================== */
+
+/* These all use the delay slot for setting the argument register, so the
+ * jump is always happening after the l.addi instruction.
+ *
+ * These are all just wrappers that don't touch the link-register r9, so the
+ * return from the "real" syscall function will return back to the syscall
+ * code that did the l.jal that brought us here.
+ */
+
+/* fork requires that we save all the callee-saved registers because they
+ * are all effectively clobbered by the call to _switch. Here we store
+ * all the registers that aren't touched by the syscall fast path and thus
+ * weren't saved there.
+ */
+
+_fork_save_extra_regs_and_call:
+ l.sw PT_GPR14(r1),r14
+ l.sw PT_GPR16(r1),r16
+ l.sw PT_GPR18(r1),r18
+ l.sw PT_GPR20(r1),r20
+ l.sw PT_GPR22(r1),r22
+ l.sw PT_GPR24(r1),r24
+ l.sw PT_GPR26(r1),r26
+ l.jr r29
+ l.sw PT_GPR28(r1),r28
+
+ENTRY(__sys_clone)
+ l.movhi r29,hi(sys_clone)
+ l.j _fork_save_extra_regs_and_call
+ l.ori r29,r29,lo(sys_clone)
+
+ENTRY(__sys_clone3)
+ l.movhi r29,hi(sys_clone3)
+ l.j _fork_save_extra_regs_and_call
+ l.ori r29,r29,lo(sys_clone3)
+
+ENTRY(__sys_fork)
+ l.movhi r29,hi(sys_fork)
+ l.j _fork_save_extra_regs_and_call
+ l.ori r29,r29,lo(sys_fork)
+
+ENTRY(sys_rt_sigreturn)
+ l.jal _sys_rt_sigreturn
+ l.addi r3,r1,0
+ l.sfne r30,r0
+ l.bnf _no_syscall_trace
+ l.nop
+ l.jal do_syscall_trace_leave
+ l.addi r3,r1,0
+_no_syscall_trace:
+ l.j _resume_userspace
+ l.nop
+
+/* This is a catch-all syscall for atomic instructions for the OpenRISC 1000.
+ * The functions takes a variable number of parameters depending on which
+ * particular flavour of atomic you want... parameter 1 is a flag identifying
+ * the atomic in question. Currently, this function implements the
+ * following variants:
+ *
+ * XCHG:
+ * @flag: 1
+ * @ptr1:
+ * @ptr2:
+ * Atomically exchange the values in pointers 1 and 2.
+ *
+ */
+
+ENTRY(sys_or1k_atomic)
+ /* FIXME: This ignores r3 and always does an XCHG */
+ DISABLE_INTERRUPTS(r17,r19)
+ l.lwz r29,0(r4)
+ l.lwz r27,0(r5)
+ l.sw 0(r4),r27
+ l.sw 0(r5),r29
+ ENABLE_INTERRUPTS(r17)
+ l.jr r9
+ l.or r11,r0,r0
+
+/* ============================================================[ EOF ]=== */
diff --git a/arch/openrisc/kernel/head.S b/arch/openrisc/kernel/head.S
new file mode 100644
index 0000000000..439e00f81e
--- /dev/null
+++ b/arch/openrisc/kernel/head.S
@@ -0,0 +1,1577 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * OpenRISC head.S
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/linkage.h>
+#include <linux/threads.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/serial_reg.h>
+#include <linux/pgtable.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/thread_info.h>
+#include <asm/cache.h>
+#include <asm/spr_defs.h>
+#include <asm/asm-offsets.h>
+#include <linux/of_fdt.h>
+
+#define tophys(rd,rs) \
+ l.movhi rd,hi(-KERNELBASE) ;\
+ l.add rd,rd,rs
+
+#define CLEAR_GPR(gpr) \
+ l.movhi gpr,0x0
+
+#define LOAD_SYMBOL_2_GPR(gpr,symbol) \
+ l.movhi gpr,hi(symbol) ;\
+ l.ori gpr,gpr,lo(symbol)
+
+
+#define UART_BASE_ADD 0x90000000
+
+#define EXCEPTION_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_DCE | SPR_SR_ICE | SPR_SR_SM)
+#define SYSCALL_SR (SPR_SR_DME | SPR_SR_IME | SPR_SR_DCE | SPR_SR_ICE | SPR_SR_IEE | SPR_SR_TEE | SPR_SR_SM)
+
+/* ============================================[ tmp store locations ]=== */
+
+#define SPR_SHADOW_GPR(x) ((x) + SPR_GPR_BASE + 32)
+
+/*
+ * emergency_print temporary stores
+ */
+#ifdef CONFIG_OPENRISC_HAVE_SHADOW_GPRS
+#define EMERGENCY_PRINT_STORE_GPR4 l.mtspr r0,r4,SPR_SHADOW_GPR(14)
+#define EMERGENCY_PRINT_LOAD_GPR4 l.mfspr r4,r0,SPR_SHADOW_GPR(14)
+
+#define EMERGENCY_PRINT_STORE_GPR5 l.mtspr r0,r5,SPR_SHADOW_GPR(15)
+#define EMERGENCY_PRINT_LOAD_GPR5 l.mfspr r5,r0,SPR_SHADOW_GPR(15)
+
+#define EMERGENCY_PRINT_STORE_GPR6 l.mtspr r0,r6,SPR_SHADOW_GPR(16)
+#define EMERGENCY_PRINT_LOAD_GPR6 l.mfspr r6,r0,SPR_SHADOW_GPR(16)
+
+#define EMERGENCY_PRINT_STORE_GPR7 l.mtspr r0,r7,SPR_SHADOW_GPR(7)
+#define EMERGENCY_PRINT_LOAD_GPR7 l.mfspr r7,r0,SPR_SHADOW_GPR(7)
+
+#define EMERGENCY_PRINT_STORE_GPR8 l.mtspr r0,r8,SPR_SHADOW_GPR(8)
+#define EMERGENCY_PRINT_LOAD_GPR8 l.mfspr r8,r0,SPR_SHADOW_GPR(8)
+
+#define EMERGENCY_PRINT_STORE_GPR9 l.mtspr r0,r9,SPR_SHADOW_GPR(9)
+#define EMERGENCY_PRINT_LOAD_GPR9 l.mfspr r9,r0,SPR_SHADOW_GPR(9)
+
+#else /* !CONFIG_OPENRISC_HAVE_SHADOW_GPRS */
+#define EMERGENCY_PRINT_STORE_GPR4 l.sw 0x20(r0),r4
+#define EMERGENCY_PRINT_LOAD_GPR4 l.lwz r4,0x20(r0)
+
+#define EMERGENCY_PRINT_STORE_GPR5 l.sw 0x24(r0),r5
+#define EMERGENCY_PRINT_LOAD_GPR5 l.lwz r5,0x24(r0)
+
+#define EMERGENCY_PRINT_STORE_GPR6 l.sw 0x28(r0),r6
+#define EMERGENCY_PRINT_LOAD_GPR6 l.lwz r6,0x28(r0)
+
+#define EMERGENCY_PRINT_STORE_GPR7 l.sw 0x2c(r0),r7
+#define EMERGENCY_PRINT_LOAD_GPR7 l.lwz r7,0x2c(r0)
+
+#define EMERGENCY_PRINT_STORE_GPR8 l.sw 0x30(r0),r8
+#define EMERGENCY_PRINT_LOAD_GPR8 l.lwz r8,0x30(r0)
+
+#define EMERGENCY_PRINT_STORE_GPR9 l.sw 0x34(r0),r9
+#define EMERGENCY_PRINT_LOAD_GPR9 l.lwz r9,0x34(r0)
+
+#endif
+
+/*
+ * TLB miss handlers temorary stores
+ */
+#ifdef CONFIG_OPENRISC_HAVE_SHADOW_GPRS
+#define EXCEPTION_STORE_GPR2 l.mtspr r0,r2,SPR_SHADOW_GPR(2)
+#define EXCEPTION_LOAD_GPR2 l.mfspr r2,r0,SPR_SHADOW_GPR(2)
+
+#define EXCEPTION_STORE_GPR3 l.mtspr r0,r3,SPR_SHADOW_GPR(3)
+#define EXCEPTION_LOAD_GPR3 l.mfspr r3,r0,SPR_SHADOW_GPR(3)
+
+#define EXCEPTION_STORE_GPR4 l.mtspr r0,r4,SPR_SHADOW_GPR(4)
+#define EXCEPTION_LOAD_GPR4 l.mfspr r4,r0,SPR_SHADOW_GPR(4)
+
+#define EXCEPTION_STORE_GPR5 l.mtspr r0,r5,SPR_SHADOW_GPR(5)
+#define EXCEPTION_LOAD_GPR5 l.mfspr r5,r0,SPR_SHADOW_GPR(5)
+
+#define EXCEPTION_STORE_GPR6 l.mtspr r0,r6,SPR_SHADOW_GPR(6)
+#define EXCEPTION_LOAD_GPR6 l.mfspr r6,r0,SPR_SHADOW_GPR(6)
+
+#else /* !CONFIG_OPENRISC_HAVE_SHADOW_GPRS */
+#define EXCEPTION_STORE_GPR2 l.sw 0x64(r0),r2
+#define EXCEPTION_LOAD_GPR2 l.lwz r2,0x64(r0)
+
+#define EXCEPTION_STORE_GPR3 l.sw 0x68(r0),r3
+#define EXCEPTION_LOAD_GPR3 l.lwz r3,0x68(r0)
+
+#define EXCEPTION_STORE_GPR4 l.sw 0x6c(r0),r4
+#define EXCEPTION_LOAD_GPR4 l.lwz r4,0x6c(r0)
+
+#define EXCEPTION_STORE_GPR5 l.sw 0x70(r0),r5
+#define EXCEPTION_LOAD_GPR5 l.lwz r5,0x70(r0)
+
+#define EXCEPTION_STORE_GPR6 l.sw 0x74(r0),r6
+#define EXCEPTION_LOAD_GPR6 l.lwz r6,0x74(r0)
+
+#endif
+
+/*
+ * EXCEPTION_HANDLE temporary stores
+ */
+
+#ifdef CONFIG_OPENRISC_HAVE_SHADOW_GPRS
+#define EXCEPTION_T_STORE_GPR30 l.mtspr r0,r30,SPR_SHADOW_GPR(30)
+#define EXCEPTION_T_LOAD_GPR30(reg) l.mfspr reg,r0,SPR_SHADOW_GPR(30)
+
+#define EXCEPTION_T_STORE_GPR10 l.mtspr r0,r10,SPR_SHADOW_GPR(10)
+#define EXCEPTION_T_LOAD_GPR10(reg) l.mfspr reg,r0,SPR_SHADOW_GPR(10)
+
+#define EXCEPTION_T_STORE_SP l.mtspr r0,r1,SPR_SHADOW_GPR(1)
+#define EXCEPTION_T_LOAD_SP(reg) l.mfspr reg,r0,SPR_SHADOW_GPR(1)
+
+#else /* !CONFIG_OPENRISC_HAVE_SHADOW_GPRS */
+#define EXCEPTION_T_STORE_GPR30 l.sw 0x78(r0),r30
+#define EXCEPTION_T_LOAD_GPR30(reg) l.lwz reg,0x78(r0)
+
+#define EXCEPTION_T_STORE_GPR10 l.sw 0x7c(r0),r10
+#define EXCEPTION_T_LOAD_GPR10(reg) l.lwz reg,0x7c(r0)
+
+#define EXCEPTION_T_STORE_SP l.sw 0x80(r0),r1
+#define EXCEPTION_T_LOAD_SP(reg) l.lwz reg,0x80(r0)
+#endif
+
+/* =========================================================[ macros ]=== */
+
+#ifdef CONFIG_SMP
+#define GET_CURRENT_PGD(reg,t1) \
+ LOAD_SYMBOL_2_GPR(reg,current_pgd) ;\
+ l.mfspr t1,r0,SPR_COREID ;\
+ l.slli t1,t1,2 ;\
+ l.add reg,reg,t1 ;\
+ tophys (t1,reg) ;\
+ l.lwz reg,0(t1)
+#else
+#define GET_CURRENT_PGD(reg,t1) \
+ LOAD_SYMBOL_2_GPR(reg,current_pgd) ;\
+ tophys (t1,reg) ;\
+ l.lwz reg,0(t1)
+#endif
+
+/* Load r10 from current_thread_info_set - clobbers r1 and r30 */
+#ifdef CONFIG_SMP
+#define GET_CURRENT_THREAD_INFO \
+ LOAD_SYMBOL_2_GPR(r1,current_thread_info_set) ;\
+ tophys (r30,r1) ;\
+ l.mfspr r10,r0,SPR_COREID ;\
+ l.slli r10,r10,2 ;\
+ l.add r30,r30,r10 ;\
+ /* r10: current_thread_info */ ;\
+ l.lwz r10,0(r30)
+#else
+#define GET_CURRENT_THREAD_INFO \
+ LOAD_SYMBOL_2_GPR(r1,current_thread_info_set) ;\
+ tophys (r30,r1) ;\
+ /* r10: current_thread_info */ ;\
+ l.lwz r10,0(r30)
+#endif
+
+/*
+ * DSCR: this is a common hook for handling exceptions. it will save
+ * the needed registers, set up stack and pointer to current
+ * then jump to the handler while enabling MMU
+ *
+ * PRMS: handler - a function to jump to. it has to save the
+ * remaining registers to kernel stack, call
+ * appropriate arch-independant exception handler
+ * and finaly jump to ret_from_except
+ *
+ * PREQ: unchanged state from the time exception happened
+ *
+ * POST: SAVED the following registers original value
+ * to the new created exception frame pointed to by r1
+ *
+ * r1 - ksp pointing to the new (exception) frame
+ * r4 - EEAR exception EA
+ * r10 - current pointing to current_thread_info struct
+ * r12 - syscall 0, since we didn't come from syscall
+ * r30 - handler address of the handler we'll jump to
+ *
+ * handler has to save remaining registers to the exception
+ * ksp frame *before* tainting them!
+ *
+ * NOTE: this function is not reentrant per se. reentrancy is guaranteed
+ * by processor disabling all exceptions/interrupts when exception
+ * accours.
+ *
+ * OPTM: no need to make it so wasteful to extract ksp when in user mode
+ */
+
+#define EXCEPTION_HANDLE(handler) \
+ EXCEPTION_T_STORE_GPR30 ;\
+ l.mfspr r30,r0,SPR_ESR_BASE ;\
+ l.andi r30,r30,SPR_SR_SM ;\
+ l.sfeqi r30,0 ;\
+ EXCEPTION_T_STORE_GPR10 ;\
+ l.bnf 2f /* kernel_mode */ ;\
+ EXCEPTION_T_STORE_SP /* delay slot */ ;\
+1: /* user_mode: */ ;\
+ GET_CURRENT_THREAD_INFO ;\
+ tophys (r30,r10) ;\
+ l.lwz r1,(TI_KSP)(r30) ;\
+ /* fall through */ ;\
+2: /* kernel_mode: */ ;\
+ /* create new stack frame, save only needed gprs */ ;\
+ /* r1: KSP, r10: current, r4: EEAR, r31: __pa(KSP) */ ;\
+ /* r12: temp, syscall indicator */ ;\
+ l.addi r1,r1,-(INT_FRAME_SIZE) ;\
+ /* r1 is KSP, r30 is __pa(KSP) */ ;\
+ tophys (r30,r1) ;\
+ l.sw PT_GPR12(r30),r12 ;\
+ /* r4 use for tmp before EA */ ;\
+ l.mfspr r12,r0,SPR_EPCR_BASE ;\
+ l.sw PT_PC(r30),r12 ;\
+ l.mfspr r12,r0,SPR_ESR_BASE ;\
+ l.sw PT_SR(r30),r12 ;\
+ /* save r30 */ ;\
+ EXCEPTION_T_LOAD_GPR30(r12) ;\
+ l.sw PT_GPR30(r30),r12 ;\
+ /* save r10 as was prior to exception */ ;\
+ EXCEPTION_T_LOAD_GPR10(r12) ;\
+ l.sw PT_GPR10(r30),r12 ;\
+ /* save PT_SP as was prior to exception */ ;\
+ EXCEPTION_T_LOAD_SP(r12) ;\
+ l.sw PT_SP(r30),r12 ;\
+ /* save exception r4, set r4 = EA */ ;\
+ l.sw PT_GPR4(r30),r4 ;\
+ l.mfspr r4,r0,SPR_EEAR_BASE ;\
+ /* r12 == 1 if we come from syscall */ ;\
+ CLEAR_GPR(r12) ;\
+ /* ----- turn on MMU ----- */ ;\
+ /* Carry DSX into exception SR */ ;\
+ l.mfspr r30,r0,SPR_SR ;\
+ l.andi r30,r30,SPR_SR_DSX ;\
+ l.ori r30,r30,(EXCEPTION_SR) ;\
+ l.mtspr r0,r30,SPR_ESR_BASE ;\
+ /* r30: EA address of handler */ ;\
+ LOAD_SYMBOL_2_GPR(r30,handler) ;\
+ l.mtspr r0,r30,SPR_EPCR_BASE ;\
+ l.rfe
+
+/*
+ * this doesn't work
+ *
+ *
+ * #ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
+ * #define UNHANDLED_EXCEPTION(handler) \
+ * l.ori r3,r0,0x1 ;\
+ * l.mtspr r0,r3,SPR_SR ;\
+ * l.movhi r3,hi(0xf0000100) ;\
+ * l.ori r3,r3,lo(0xf0000100) ;\
+ * l.jr r3 ;\
+ * l.nop 1
+ *
+ * #endif
+ */
+
+/* DSCR: this is the same as EXCEPTION_HANDLE(), we are just
+ * a bit more carefull (if we have a PT_SP or current pointer
+ * corruption) and set them up from 'current_set'
+ *
+ */
+#define UNHANDLED_EXCEPTION(handler) \
+ EXCEPTION_T_STORE_GPR30 ;\
+ EXCEPTION_T_STORE_GPR10 ;\
+ EXCEPTION_T_STORE_SP ;\
+ /* temporary store r3, r9 into r1, r10 */ ;\
+ l.addi r1,r3,0x0 ;\
+ l.addi r10,r9,0x0 ;\
+ LOAD_SYMBOL_2_GPR(r9,_string_unhandled_exception) ;\
+ tophys (r3,r9) ;\
+ l.jal _emergency_print ;\
+ l.nop ;\
+ l.mfspr r3,r0,SPR_NPC ;\
+ l.jal _emergency_print_nr ;\
+ l.andi r3,r3,0x1f00 ;\
+ LOAD_SYMBOL_2_GPR(r9,_string_epc_prefix) ;\
+ tophys (r3,r9) ;\
+ l.jal _emergency_print ;\
+ l.nop ;\
+ l.jal _emergency_print_nr ;\
+ l.mfspr r3,r0,SPR_EPCR_BASE ;\
+ LOAD_SYMBOL_2_GPR(r9,_string_nl) ;\
+ tophys (r3,r9) ;\
+ l.jal _emergency_print ;\
+ l.nop ;\
+ /* end of printing */ ;\
+ l.addi r3,r1,0x0 ;\
+ l.addi r9,r10,0x0 ;\
+ /* extract current, ksp from current_set */ ;\
+ LOAD_SYMBOL_2_GPR(r1,_unhandled_stack_top) ;\
+ LOAD_SYMBOL_2_GPR(r10,init_thread_union) ;\
+ /* create new stack frame, save only needed gprs */ ;\
+ /* r1: KSP, r10: current, r31: __pa(KSP) */ ;\
+ /* r12: temp, syscall indicator, r13 temp */ ;\
+ l.addi r1,r1,-(INT_FRAME_SIZE) ;\
+ /* r1 is KSP, r30 is __pa(KSP) */ ;\
+ tophys (r30,r1) ;\
+ l.sw PT_GPR12(r30),r12 ;\
+ l.mfspr r12,r0,SPR_EPCR_BASE ;\
+ l.sw PT_PC(r30),r12 ;\
+ l.mfspr r12,r0,SPR_ESR_BASE ;\
+ l.sw PT_SR(r30),r12 ;\
+ /* save r31 */ ;\
+ EXCEPTION_T_LOAD_GPR30(r12) ;\
+ l.sw PT_GPR30(r30),r12 ;\
+ /* save r10 as was prior to exception */ ;\
+ EXCEPTION_T_LOAD_GPR10(r12) ;\
+ l.sw PT_GPR10(r30),r12 ;\
+ /* save PT_SP as was prior to exception */ ;\
+ EXCEPTION_T_LOAD_SP(r12) ;\
+ l.sw PT_SP(r30),r12 ;\
+ l.sw PT_GPR13(r30),r13 ;\
+ /* --> */ ;\
+ /* save exception r4, set r4 = EA */ ;\
+ l.sw PT_GPR4(r30),r4 ;\
+ l.mfspr r4,r0,SPR_EEAR_BASE ;\
+ /* r12 == 1 if we come from syscall */ ;\
+ CLEAR_GPR(r12) ;\
+ /* ----- play a MMU trick ----- */ ;\
+ l.ori r30,r0,(EXCEPTION_SR) ;\
+ l.mtspr r0,r30,SPR_ESR_BASE ;\
+ /* r31: EA address of handler */ ;\
+ LOAD_SYMBOL_2_GPR(r30,handler) ;\
+ l.mtspr r0,r30,SPR_EPCR_BASE ;\
+ l.rfe
+
+/* =====================================================[ exceptions] === */
+
+/* ---[ 0x100: RESET exception ]----------------------------------------- */
+ .org 0x100
+ /* Jump to .init code at _start which lives in the .head section
+ * and will be discarded after boot.
+ */
+ LOAD_SYMBOL_2_GPR(r15, _start)
+ tophys (r13,r15) /* MMU disabled */
+ l.jr r13
+ l.nop
+
+/* ---[ 0x200: BUS exception ]------------------------------------------- */
+ .org 0x200
+_dispatch_bus_fault:
+ EXCEPTION_HANDLE(_bus_fault_handler)
+
+/* ---[ 0x300: Data Page Fault exception ]------------------------------- */
+ .org 0x300
+_dispatch_do_dpage_fault:
+// totaly disable timer interrupt
+// l.mtspr r0,r0,SPR_TTMR
+// DEBUG_TLB_PROBE(0x300)
+// EXCEPTION_DEBUG_VALUE_ER_ENABLED(0x300)
+ EXCEPTION_HANDLE(_data_page_fault_handler)
+
+/* ---[ 0x400: Insn Page Fault exception ]------------------------------- */
+ .org 0x400
+_dispatch_do_ipage_fault:
+// totaly disable timer interrupt
+// l.mtspr r0,r0,SPR_TTMR
+// DEBUG_TLB_PROBE(0x400)
+// EXCEPTION_DEBUG_VALUE_ER_ENABLED(0x400)
+ EXCEPTION_HANDLE(_insn_page_fault_handler)
+
+/* ---[ 0x500: Timer exception ]----------------------------------------- */
+ .org 0x500
+ EXCEPTION_HANDLE(_timer_handler)
+
+/* ---[ 0x600: Alignment exception ]-------------------------------------- */
+ .org 0x600
+ EXCEPTION_HANDLE(_alignment_handler)
+
+/* ---[ 0x700: Illegal insn exception ]---------------------------------- */
+ .org 0x700
+ EXCEPTION_HANDLE(_illegal_instruction_handler)
+
+/* ---[ 0x800: External interrupt exception ]---------------------------- */
+ .org 0x800
+ EXCEPTION_HANDLE(_external_irq_handler)
+
+/* ---[ 0x900: DTLB miss exception ]------------------------------------- */
+ .org 0x900
+ l.j boot_dtlb_miss_handler
+ l.nop
+
+/* ---[ 0xa00: ITLB miss exception ]------------------------------------- */
+ .org 0xa00
+ l.j boot_itlb_miss_handler
+ l.nop
+
+/* ---[ 0xb00: Range exception ]----------------------------------------- */
+ .org 0xb00
+ UNHANDLED_EXCEPTION(_vector_0xb00)
+
+/* ---[ 0xc00: Syscall exception ]--------------------------------------- */
+ .org 0xc00
+ EXCEPTION_HANDLE(_sys_call_handler)
+
+/* ---[ 0xd00: Floating point exception ]--------------------------------- */
+ .org 0xd00
+ EXCEPTION_HANDLE(_fpe_trap_handler)
+
+/* ---[ 0xe00: Trap exception ]------------------------------------------ */
+ .org 0xe00
+// UNHANDLED_EXCEPTION(_vector_0xe00)
+ EXCEPTION_HANDLE(_trap_handler)
+
+/* ---[ 0xf00: Reserved exception ]-------------------------------------- */
+ .org 0xf00
+ UNHANDLED_EXCEPTION(_vector_0xf00)
+
+/* ---[ 0x1000: Reserved exception ]------------------------------------- */
+ .org 0x1000
+ UNHANDLED_EXCEPTION(_vector_0x1000)
+
+/* ---[ 0x1100: Reserved exception ]------------------------------------- */
+ .org 0x1100
+ UNHANDLED_EXCEPTION(_vector_0x1100)
+
+/* ---[ 0x1200: Reserved exception ]------------------------------------- */
+ .org 0x1200
+ UNHANDLED_EXCEPTION(_vector_0x1200)
+
+/* ---[ 0x1300: Reserved exception ]------------------------------------- */
+ .org 0x1300
+ UNHANDLED_EXCEPTION(_vector_0x1300)
+
+/* ---[ 0x1400: Reserved exception ]------------------------------------- */
+ .org 0x1400
+ UNHANDLED_EXCEPTION(_vector_0x1400)
+
+/* ---[ 0x1500: Reserved exception ]------------------------------------- */
+ .org 0x1500
+ UNHANDLED_EXCEPTION(_vector_0x1500)
+
+/* ---[ 0x1600: Reserved exception ]------------------------------------- */
+ .org 0x1600
+ UNHANDLED_EXCEPTION(_vector_0x1600)
+
+/* ---[ 0x1700: Reserved exception ]------------------------------------- */
+ .org 0x1700
+ UNHANDLED_EXCEPTION(_vector_0x1700)
+
+/* ---[ 0x1800: Reserved exception ]------------------------------------- */
+ .org 0x1800
+ UNHANDLED_EXCEPTION(_vector_0x1800)
+
+/* ---[ 0x1900: Reserved exception ]------------------------------------- */
+ .org 0x1900
+ UNHANDLED_EXCEPTION(_vector_0x1900)
+
+/* ---[ 0x1a00: Reserved exception ]------------------------------------- */
+ .org 0x1a00
+ UNHANDLED_EXCEPTION(_vector_0x1a00)
+
+/* ---[ 0x1b00: Reserved exception ]------------------------------------- */
+ .org 0x1b00
+ UNHANDLED_EXCEPTION(_vector_0x1b00)
+
+/* ---[ 0x1c00: Reserved exception ]------------------------------------- */
+ .org 0x1c00
+ UNHANDLED_EXCEPTION(_vector_0x1c00)
+
+/* ---[ 0x1d00: Reserved exception ]------------------------------------- */
+ .org 0x1d00
+ UNHANDLED_EXCEPTION(_vector_0x1d00)
+
+/* ---[ 0x1e00: Reserved exception ]------------------------------------- */
+ .org 0x1e00
+ UNHANDLED_EXCEPTION(_vector_0x1e00)
+
+/* ---[ 0x1f00: Reserved exception ]------------------------------------- */
+ .org 0x1f00
+ UNHANDLED_EXCEPTION(_vector_0x1f00)
+
+ .org 0x2000
+/* ===================================================[ kernel start ]=== */
+
+/* .text*/
+
+/* This early stuff belongs in HEAD, but some of the functions below definitely
+ * don't... */
+
+ __HEAD
+ .global _start
+_start:
+ /* Init r0 to zero as per spec */
+ CLEAR_GPR(r0)
+
+ /* save kernel parameters */
+ l.or r25,r0,r3 /* pointer to fdt */
+
+ /*
+ * ensure a deterministic start
+ */
+
+ l.ori r3,r0,0x1
+ l.mtspr r0,r3,SPR_SR
+
+ /*
+ * Start the TTCR as early as possible, so that the RNG can make use of
+ * measurements of boot time from the earliest opportunity. Especially
+ * important is that the TTCR does not return zero by the time we reach
+ * random_init().
+ */
+ l.movhi r3,hi(SPR_TTMR_CR)
+ l.mtspr r0,r3,SPR_TTMR
+
+ CLEAR_GPR(r1)
+ CLEAR_GPR(r2)
+ CLEAR_GPR(r3)
+ CLEAR_GPR(r4)
+ CLEAR_GPR(r5)
+ CLEAR_GPR(r6)
+ CLEAR_GPR(r7)
+ CLEAR_GPR(r8)
+ CLEAR_GPR(r9)
+ CLEAR_GPR(r10)
+ CLEAR_GPR(r11)
+ CLEAR_GPR(r12)
+ CLEAR_GPR(r13)
+ CLEAR_GPR(r14)
+ CLEAR_GPR(r15)
+ CLEAR_GPR(r16)
+ CLEAR_GPR(r17)
+ CLEAR_GPR(r18)
+ CLEAR_GPR(r19)
+ CLEAR_GPR(r20)
+ CLEAR_GPR(r21)
+ CLEAR_GPR(r22)
+ CLEAR_GPR(r23)
+ CLEAR_GPR(r24)
+ CLEAR_GPR(r26)
+ CLEAR_GPR(r27)
+ CLEAR_GPR(r28)
+ CLEAR_GPR(r29)
+ CLEAR_GPR(r30)
+ CLEAR_GPR(r31)
+
+#ifdef CONFIG_SMP
+ l.mfspr r26,r0,SPR_COREID
+ l.sfeq r26,r0
+ l.bnf secondary_wait
+ l.nop
+#endif
+ /*
+ * set up initial ksp and current
+ */
+ /* setup kernel stack */
+ LOAD_SYMBOL_2_GPR(r1,init_thread_union + THREAD_SIZE)
+ LOAD_SYMBOL_2_GPR(r10,init_thread_union) // setup current
+ tophys (r31,r10)
+ l.sw TI_KSP(r31), r1
+
+ l.ori r4,r0,0x0
+
+
+ /*
+ * .data contains initialized data,
+ * .bss contains uninitialized data - clear it up
+ */
+clear_bss:
+ LOAD_SYMBOL_2_GPR(r24, __bss_start)
+ LOAD_SYMBOL_2_GPR(r26, _end)
+ tophys(r28,r24)
+ tophys(r30,r26)
+ CLEAR_GPR(r24)
+ CLEAR_GPR(r26)
+1:
+ l.sw (0)(r28),r0
+ l.sfltu r28,r30
+ l.bf 1b
+ l.addi r28,r28,4
+
+enable_ic:
+ l.jal _ic_enable
+ l.nop
+
+enable_dc:
+ l.jal _dc_enable
+ l.nop
+
+flush_tlb:
+ l.jal _flush_tlb
+ l.nop
+
+/* The MMU needs to be enabled before or1k_early_setup is called */
+
+enable_mmu:
+ /*
+ * enable dmmu & immu
+ * SR[5] = 0, SR[6] = 0, 6th and 7th bit of SR set to 0
+ */
+ l.mfspr r30,r0,SPR_SR
+ l.movhi r28,hi(SPR_SR_DME | SPR_SR_IME)
+ l.ori r28,r28,lo(SPR_SR_DME | SPR_SR_IME)
+ l.or r30,r30,r28
+ l.mtspr r0,r30,SPR_SR
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+
+ // reset the simulation counters
+ l.nop 5
+
+ /* check fdt header magic word */
+ l.lwz r3,0(r25) /* load magic from fdt into r3 */
+ l.movhi r4,hi(OF_DT_HEADER)
+ l.ori r4,r4,lo(OF_DT_HEADER)
+ l.sfeq r3,r4
+ l.bf _fdt_found
+ l.nop
+ /* magic number mismatch, set fdt pointer to null */
+ l.or r25,r0,r0
+_fdt_found:
+ /* pass fdt pointer to or1k_early_setup in r3 */
+ l.or r3,r0,r25
+ LOAD_SYMBOL_2_GPR(r24, or1k_early_setup)
+ l.jalr r24
+ l.nop
+
+clear_regs:
+ /*
+ * clear all GPRS to increase determinism
+ */
+ CLEAR_GPR(r2)
+ CLEAR_GPR(r3)
+ CLEAR_GPR(r4)
+ CLEAR_GPR(r5)
+ CLEAR_GPR(r6)
+ CLEAR_GPR(r7)
+ CLEAR_GPR(r8)
+ CLEAR_GPR(r9)
+ CLEAR_GPR(r11)
+ CLEAR_GPR(r12)
+ CLEAR_GPR(r13)
+ CLEAR_GPR(r14)
+ CLEAR_GPR(r15)
+ CLEAR_GPR(r16)
+ CLEAR_GPR(r17)
+ CLEAR_GPR(r18)
+ CLEAR_GPR(r19)
+ CLEAR_GPR(r20)
+ CLEAR_GPR(r21)
+ CLEAR_GPR(r22)
+ CLEAR_GPR(r23)
+ CLEAR_GPR(r24)
+ CLEAR_GPR(r25)
+ CLEAR_GPR(r26)
+ CLEAR_GPR(r27)
+ CLEAR_GPR(r28)
+ CLEAR_GPR(r29)
+ CLEAR_GPR(r30)
+ CLEAR_GPR(r31)
+
+jump_start_kernel:
+ /*
+ * jump to kernel entry (start_kernel)
+ */
+ LOAD_SYMBOL_2_GPR(r30, start_kernel)
+ l.jr r30
+ l.nop
+
+_flush_tlb:
+ /*
+ * I N V A L I D A T E T L B e n t r i e s
+ */
+ LOAD_SYMBOL_2_GPR(r5,SPR_DTLBMR_BASE(0))
+ LOAD_SYMBOL_2_GPR(r6,SPR_ITLBMR_BASE(0))
+ l.addi r7,r0,128 /* Maximum number of sets */
+1:
+ l.mtspr r5,r0,0x0
+ l.mtspr r6,r0,0x0
+
+ l.addi r5,r5,1
+ l.addi r6,r6,1
+ l.sfeq r7,r0
+ l.bnf 1b
+ l.addi r7,r7,-1
+
+ l.jr r9
+ l.nop
+
+#ifdef CONFIG_SMP
+secondary_wait:
+ /* Doze the cpu until we are asked to run */
+ /* If we dont have power management skip doze */
+ l.mfspr r25,r0,SPR_UPR
+ l.andi r25,r25,SPR_UPR_PMP
+ l.sfeq r25,r0
+ l.bf secondary_check_release
+ l.nop
+
+ /* Setup special secondary exception handler */
+ LOAD_SYMBOL_2_GPR(r3, _secondary_evbar)
+ tophys(r25,r3)
+ l.mtspr r0,r25,SPR_EVBAR
+
+ /* Enable Interrupts */
+ l.mfspr r25,r0,SPR_SR
+ l.ori r25,r25,SPR_SR_IEE
+ l.mtspr r0,r25,SPR_SR
+
+ /* Unmask interrupts interrupts */
+ l.mfspr r25,r0,SPR_PICMR
+ l.ori r25,r25,0xffff
+ l.mtspr r0,r25,SPR_PICMR
+
+ /* Doze */
+ l.mfspr r25,r0,SPR_PMR
+ LOAD_SYMBOL_2_GPR(r3, SPR_PMR_DME)
+ l.or r25,r25,r3
+ l.mtspr r0,r25,SPR_PMR
+
+ /* Wakeup - Restore exception handler */
+ l.mtspr r0,r0,SPR_EVBAR
+
+secondary_check_release:
+ /*
+ * Check if we actually got the release signal, if not go-back to
+ * sleep.
+ */
+ l.mfspr r25,r0,SPR_COREID
+ LOAD_SYMBOL_2_GPR(r3, secondary_release)
+ tophys(r4, r3)
+ l.lwz r3,0(r4)
+ l.sfeq r25,r3
+ l.bnf secondary_wait
+ l.nop
+ /* fall through to secondary_init */
+
+secondary_init:
+ /*
+ * set up initial ksp and current
+ */
+ LOAD_SYMBOL_2_GPR(r10, secondary_thread_info)
+ tophys (r30,r10)
+ l.lwz r10,0(r30)
+ l.addi r1,r10,THREAD_SIZE
+ tophys (r30,r10)
+ l.sw TI_KSP(r30),r1
+
+ l.jal _ic_enable
+ l.nop
+
+ l.jal _dc_enable
+ l.nop
+
+ l.jal _flush_tlb
+ l.nop
+
+ /*
+ * enable dmmu & immu
+ */
+ l.mfspr r30,r0,SPR_SR
+ l.movhi r28,hi(SPR_SR_DME | SPR_SR_IME)
+ l.ori r28,r28,lo(SPR_SR_DME | SPR_SR_IME)
+ l.or r30,r30,r28
+ /*
+ * This is a bit tricky, we need to switch over from physical addresses
+ * to virtual addresses on the fly.
+ * To do that, we first set up ESR with the IME and DME bits set.
+ * Then EPCR is set to secondary_start and then a l.rfe is issued to
+ * "jump" to that.
+ */
+ l.mtspr r0,r30,SPR_ESR_BASE
+ LOAD_SYMBOL_2_GPR(r30, secondary_start)
+ l.mtspr r0,r30,SPR_EPCR_BASE
+ l.rfe
+
+secondary_start:
+ LOAD_SYMBOL_2_GPR(r30, secondary_start_kernel)
+ l.jr r30
+ l.nop
+
+#endif
+
+/* ========================================[ cache ]=== */
+
+ /* alignment here so we don't change memory offsets with
+ * memory controller defined
+ */
+ .align 0x2000
+
+_ic_enable:
+ /* Check if IC present and skip enabling otherwise */
+ l.mfspr r24,r0,SPR_UPR
+ l.andi r26,r24,SPR_UPR_ICP
+ l.sfeq r26,r0
+ l.bf 9f
+ l.nop
+
+ /* Disable IC */
+ l.mfspr r6,r0,SPR_SR
+ l.addi r5,r0,-1
+ l.xori r5,r5,SPR_SR_ICE
+ l.and r5,r6,r5
+ l.mtspr r0,r5,SPR_SR
+
+ /* Establish cache block size
+ If BS=0, 16;
+ If BS=1, 32;
+ r14 contain block size
+ */
+ l.mfspr r24,r0,SPR_ICCFGR
+ l.andi r26,r24,SPR_ICCFGR_CBS
+ l.srli r28,r26,7
+ l.ori r30,r0,16
+ l.sll r14,r30,r28
+
+ /* Establish number of cache sets
+ r16 contains number of cache sets
+ r28 contains log(# of cache sets)
+ */
+ l.andi r26,r24,SPR_ICCFGR_NCS
+ l.srli r28,r26,3
+ l.ori r30,r0,1
+ l.sll r16,r30,r28
+
+ /* Invalidate IC */
+ l.addi r6,r0,0
+ l.sll r5,r14,r28
+// l.mul r5,r14,r16
+// l.trap 1
+// l.addi r5,r0,IC_SIZE
+1:
+ l.mtspr r0,r6,SPR_ICBIR
+ l.sfne r6,r5
+ l.bf 1b
+ l.add r6,r6,r14
+ // l.addi r6,r6,IC_LINE
+
+ /* Enable IC */
+ l.mfspr r6,r0,SPR_SR
+ l.ori r6,r6,SPR_SR_ICE
+ l.mtspr r0,r6,SPR_SR
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+9:
+ l.jr r9
+ l.nop
+
+_dc_enable:
+ /* Check if DC present and skip enabling otherwise */
+ l.mfspr r24,r0,SPR_UPR
+ l.andi r26,r24,SPR_UPR_DCP
+ l.sfeq r26,r0
+ l.bf 9f
+ l.nop
+
+ /* Disable DC */
+ l.mfspr r6,r0,SPR_SR
+ l.addi r5,r0,-1
+ l.xori r5,r5,SPR_SR_DCE
+ l.and r5,r6,r5
+ l.mtspr r0,r5,SPR_SR
+
+ /* Establish cache block size
+ If BS=0, 16;
+ If BS=1, 32;
+ r14 contain block size
+ */
+ l.mfspr r24,r0,SPR_DCCFGR
+ l.andi r26,r24,SPR_DCCFGR_CBS
+ l.srli r28,r26,7
+ l.ori r30,r0,16
+ l.sll r14,r30,r28
+
+ /* Establish number of cache sets
+ r16 contains number of cache sets
+ r28 contains log(# of cache sets)
+ */
+ l.andi r26,r24,SPR_DCCFGR_NCS
+ l.srli r28,r26,3
+ l.ori r30,r0,1
+ l.sll r16,r30,r28
+
+ /* Invalidate DC */
+ l.addi r6,r0,0
+ l.sll r5,r14,r28
+1:
+ l.mtspr r0,r6,SPR_DCBIR
+ l.sfne r6,r5
+ l.bf 1b
+ l.add r6,r6,r14
+
+ /* Enable DC */
+ l.mfspr r6,r0,SPR_SR
+ l.ori r6,r6,SPR_SR_DCE
+ l.mtspr r0,r6,SPR_SR
+9:
+ l.jr r9
+ l.nop
+
+/* ===============================================[ page table masks ]=== */
+
+#define DTLB_UP_CONVERT_MASK 0x3fa
+#define ITLB_UP_CONVERT_MASK 0x3a
+
+/* for SMP we'd have (this is a bit subtle, CC must be always set
+ * for SMP, but since we have _PAGE_PRESENT bit always defined
+ * we can just modify the mask)
+ */
+#define DTLB_SMP_CONVERT_MASK 0x3fb
+#define ITLB_SMP_CONVERT_MASK 0x3b
+
+/* ---[ boot dtlb miss handler ]----------------------------------------- */
+
+boot_dtlb_miss_handler:
+
+/* mask for DTLB_MR register: - (0) sets V (valid) bit,
+ * - (31-12) sets bits belonging to VPN (31-12)
+ */
+#define DTLB_MR_MASK 0xfffff001
+
+/* mask for DTLB_TR register: - (2) sets CI (cache inhibit) bit,
+ * - (4) sets A (access) bit,
+ * - (5) sets D (dirty) bit,
+ * - (8) sets SRE (superuser read) bit
+ * - (9) sets SWE (superuser write) bit
+ * - (31-12) sets bits belonging to VPN (31-12)
+ */
+#define DTLB_TR_MASK 0xfffff332
+
+/* These are for masking out the VPN/PPN value from the MR/TR registers...
+ * it's not the same as the PFN */
+#define VPN_MASK 0xfffff000
+#define PPN_MASK 0xfffff000
+
+
+ EXCEPTION_STORE_GPR6
+
+#if 0
+ l.mfspr r6,r0,SPR_ESR_BASE //
+ l.andi r6,r6,SPR_SR_SM // are we in kernel mode ?
+ l.sfeqi r6,0 // r6 == 0x1 --> SM
+ l.bf exit_with_no_dtranslation //
+ l.nop
+#endif
+
+ /* this could be optimized by moving storing of
+ * non r6 registers here, and jumping r6 restore
+ * if not in supervisor mode
+ */
+
+ EXCEPTION_STORE_GPR2
+ EXCEPTION_STORE_GPR3
+ EXCEPTION_STORE_GPR4
+ EXCEPTION_STORE_GPR5
+
+ l.mfspr r4,r0,SPR_EEAR_BASE // get the offending EA
+
+immediate_translation:
+ CLEAR_GPR(r6)
+
+ l.srli r3,r4,0xd // r3 <- r4 / 8192 (sets are relative to page size (8Kb) NOT VPN size (4Kb)
+
+ l.mfspr r6, r0, SPR_DMMUCFGR
+ l.andi r6, r6, SPR_DMMUCFGR_NTS
+ l.srli r6, r6, SPR_DMMUCFGR_NTS_OFF
+ l.ori r5, r0, 0x1
+ l.sll r5, r5, r6 // r5 = number DMMU sets
+ l.addi r6, r5, -1 // r6 = nsets mask
+ l.and r2, r3, r6 // r2 <- r3 % NSETS_MASK
+
+ l.or r6,r6,r4 // r6 <- r4
+ l.ori r6,r6,~(VPN_MASK) // r6 <- VPN :VPN .xfff - clear up lo(r6) to 0x**** *fff
+ l.movhi r5,hi(DTLB_MR_MASK) // r5 <- ffff:0000.x000
+ l.ori r5,r5,lo(DTLB_MR_MASK) // r5 <- ffff:1111.x001 - apply DTLB_MR_MASK
+ l.and r5,r5,r6 // r5 <- VPN :VPN .x001 - we have DTLBMR entry
+ l.mtspr r2,r5,SPR_DTLBMR_BASE(0) // set DTLBMR
+
+ /* set up DTLB with no translation for EA <= 0xbfffffff */
+ LOAD_SYMBOL_2_GPR(r6,0xbfffffff)
+ l.sfgeu r6,r4 // flag if r6 >= r4 (if 0xbfffffff >= EA)
+ l.bf 1f // goto out
+ l.and r3,r4,r4 // delay slot :: 24 <- r4 (if flag==1)
+
+ tophys(r3,r4) // r3 <- PA
+1:
+ l.ori r3,r3,~(PPN_MASK) // r3 <- PPN :PPN .xfff - clear up lo(r6) to 0x**** *fff
+ l.movhi r5,hi(DTLB_TR_MASK) // r5 <- ffff:0000.x000
+ l.ori r5,r5,lo(DTLB_TR_MASK) // r5 <- ffff:1111.x330 - apply DTLB_MR_MASK
+ l.and r5,r5,r3 // r5 <- PPN :PPN .x330 - we have DTLBTR entry
+ l.mtspr r2,r5,SPR_DTLBTR_BASE(0) // set DTLBTR
+
+ EXCEPTION_LOAD_GPR6
+ EXCEPTION_LOAD_GPR5
+ EXCEPTION_LOAD_GPR4
+ EXCEPTION_LOAD_GPR3
+ EXCEPTION_LOAD_GPR2
+
+ l.rfe // SR <- ESR, PC <- EPC
+
+exit_with_no_dtranslation:
+ /* EA out of memory or not in supervisor mode */
+ EXCEPTION_LOAD_GPR6
+ EXCEPTION_LOAD_GPR4
+ l.j _dispatch_bus_fault
+
+/* ---[ boot itlb miss handler ]----------------------------------------- */
+
+boot_itlb_miss_handler:
+
+/* mask for ITLB_MR register: - sets V (valid) bit,
+ * - sets bits belonging to VPN (15-12)
+ */
+#define ITLB_MR_MASK 0xfffff001
+
+/* mask for ITLB_TR register: - sets A (access) bit,
+ * - sets SXE (superuser execute) bit
+ * - sets bits belonging to VPN (15-12)
+ */
+#define ITLB_TR_MASK 0xfffff050
+
+/*
+#define VPN_MASK 0xffffe000
+#define PPN_MASK 0xffffe000
+*/
+
+
+
+ EXCEPTION_STORE_GPR2
+ EXCEPTION_STORE_GPR3
+ EXCEPTION_STORE_GPR4
+ EXCEPTION_STORE_GPR5
+ EXCEPTION_STORE_GPR6
+
+#if 0
+ l.mfspr r6,r0,SPR_ESR_BASE //
+ l.andi r6,r6,SPR_SR_SM // are we in kernel mode ?
+ l.sfeqi r6,0 // r6 == 0x1 --> SM
+ l.bf exit_with_no_itranslation
+ l.nop
+#endif
+
+
+ l.mfspr r4,r0,SPR_EEAR_BASE // get the offending EA
+
+earlyearly:
+ CLEAR_GPR(r6)
+
+ l.srli r3,r4,0xd // r3 <- r4 / 8192 (sets are relative to page size (8Kb) NOT VPN size (4Kb)
+
+ l.mfspr r6, r0, SPR_IMMUCFGR
+ l.andi r6, r6, SPR_IMMUCFGR_NTS
+ l.srli r6, r6, SPR_IMMUCFGR_NTS_OFF
+ l.ori r5, r0, 0x1
+ l.sll r5, r5, r6 // r5 = number IMMU sets from IMMUCFGR
+ l.addi r6, r5, -1 // r6 = nsets mask
+ l.and r2, r3, r6 // r2 <- r3 % NSETS_MASK
+
+ l.or r6,r6,r4 // r6 <- r4
+ l.ori r6,r6,~(VPN_MASK) // r6 <- VPN :VPN .xfff - clear up lo(r6) to 0x**** *fff
+ l.movhi r5,hi(ITLB_MR_MASK) // r5 <- ffff:0000.x000
+ l.ori r5,r5,lo(ITLB_MR_MASK) // r5 <- ffff:1111.x001 - apply ITLB_MR_MASK
+ l.and r5,r5,r6 // r5 <- VPN :VPN .x001 - we have ITLBMR entry
+ l.mtspr r2,r5,SPR_ITLBMR_BASE(0) // set ITLBMR
+
+ /*
+ * set up ITLB with no translation for EA <= 0x0fffffff
+ *
+ * we need this for head.S mapping (EA = PA). if we move all functions
+ * which run with mmu enabled into entry.S, we might be able to eliminate this.
+ *
+ */
+ LOAD_SYMBOL_2_GPR(r6,0x0fffffff)
+ l.sfgeu r6,r4 // flag if r6 >= r4 (if 0xb0ffffff >= EA)
+ l.bf 1f // goto out
+ l.and r3,r4,r4 // delay slot :: 24 <- r4 (if flag==1)
+
+ tophys(r3,r4) // r3 <- PA
+1:
+ l.ori r3,r3,~(PPN_MASK) // r3 <- PPN :PPN .xfff - clear up lo(r6) to 0x**** *fff
+ l.movhi r5,hi(ITLB_TR_MASK) // r5 <- ffff:0000.x000
+ l.ori r5,r5,lo(ITLB_TR_MASK) // r5 <- ffff:1111.x050 - apply ITLB_MR_MASK
+ l.and r5,r5,r3 // r5 <- PPN :PPN .x050 - we have ITLBTR entry
+ l.mtspr r2,r5,SPR_ITLBTR_BASE(0) // set ITLBTR
+
+ EXCEPTION_LOAD_GPR6
+ EXCEPTION_LOAD_GPR5
+ EXCEPTION_LOAD_GPR4
+ EXCEPTION_LOAD_GPR3
+ EXCEPTION_LOAD_GPR2
+
+ l.rfe // SR <- ESR, PC <- EPC
+
+exit_with_no_itranslation:
+ EXCEPTION_LOAD_GPR4
+ EXCEPTION_LOAD_GPR6
+ l.j _dispatch_bus_fault
+ l.nop
+
+/* ====================================================================== */
+/*
+ * Stuff below here shouldn't go into .head section... maybe this stuff
+ * can be moved to entry.S ???
+ */
+
+/* ==============================================[ DTLB miss handler ]=== */
+
+/*
+ * Comments:
+ * Exception handlers are entered with MMU off so the following handler
+ * needs to use physical addressing
+ *
+ */
+
+ .text
+ENTRY(dtlb_miss_handler)
+ EXCEPTION_STORE_GPR2
+ EXCEPTION_STORE_GPR3
+ EXCEPTION_STORE_GPR4
+ /*
+ * get EA of the miss
+ */
+ l.mfspr r2,r0,SPR_EEAR_BASE
+ /*
+ * pmd = (pmd_t *)(current_pgd + pgd_index(daddr));
+ */
+ GET_CURRENT_PGD(r3,r4) // r3 is current_pgd, r4 is temp
+ l.srli r4,r2,0x18 // >> PAGE_SHIFT + (PAGE_SHIFT - 2)
+ l.slli r4,r4,0x2 // to get address << 2
+ l.add r3,r4,r3 // r4 is pgd_index(daddr)
+ /*
+ * if (pmd_none(*pmd))
+ * goto pmd_none:
+ */
+ tophys (r4,r3)
+ l.lwz r3,0x0(r4) // get *pmd value
+ l.sfne r3,r0
+ l.bnf d_pmd_none
+ l.addi r3,r0,0xffffe000 // PAGE_MASK
+
+d_pmd_good:
+ /*
+ * pte = *pte_offset(pmd, daddr);
+ */
+ l.lwz r4,0x0(r4) // get **pmd value
+ l.and r4,r4,r3 // & PAGE_MASK
+ l.srli r2,r2,0xd // >> PAGE_SHIFT, r2 == EEAR
+ l.andi r3,r2,0x7ff // (1UL << PAGE_SHIFT - 2) - 1
+ l.slli r3,r3,0x2 // to get address << 2
+ l.add r3,r3,r4
+ l.lwz r3,0x0(r3) // this is pte at last
+ /*
+ * if (!pte_present(pte))
+ */
+ l.andi r4,r3,0x1
+ l.sfne r4,r0 // is pte present
+ l.bnf d_pte_not_present
+ l.addi r4,r0,0xffffe3fa // PAGE_MASK | DTLB_UP_CONVERT_MASK
+ /*
+ * fill DTLB TR register
+ */
+ l.and r4,r3,r4 // apply the mask
+ // Determine number of DMMU sets
+ l.mfspr r2, r0, SPR_DMMUCFGR
+ l.andi r2, r2, SPR_DMMUCFGR_NTS
+ l.srli r2, r2, SPR_DMMUCFGR_NTS_OFF
+ l.ori r3, r0, 0x1
+ l.sll r3, r3, r2 // r3 = number DMMU sets DMMUCFGR
+ l.addi r2, r3, -1 // r2 = nsets mask
+ l.mfspr r3, r0, SPR_EEAR_BASE
+ l.srli r3, r3, 0xd // >> PAGE_SHIFT
+ l.and r2, r3, r2 // calc offset: & (NUM_TLB_ENTRIES-1)
+ //NUM_TLB_ENTRIES
+ l.mtspr r2,r4,SPR_DTLBTR_BASE(0)
+ /*
+ * fill DTLB MR register
+ */
+ l.slli r3, r3, 0xd /* << PAGE_SHIFT => EA & PAGE_MASK */
+ l.ori r4,r3,0x1 // set hardware valid bit: DTBL_MR entry
+ l.mtspr r2,r4,SPR_DTLBMR_BASE(0)
+
+ EXCEPTION_LOAD_GPR2
+ EXCEPTION_LOAD_GPR3
+ EXCEPTION_LOAD_GPR4
+ l.rfe
+d_pmd_none:
+d_pte_not_present:
+ EXCEPTION_LOAD_GPR2
+ EXCEPTION_LOAD_GPR3
+ EXCEPTION_LOAD_GPR4
+ EXCEPTION_HANDLE(_dtlb_miss_page_fault_handler)
+
+/* ==============================================[ ITLB miss handler ]=== */
+ENTRY(itlb_miss_handler)
+ EXCEPTION_STORE_GPR2
+ EXCEPTION_STORE_GPR3
+ EXCEPTION_STORE_GPR4
+ /*
+ * get EA of the miss
+ */
+ l.mfspr r2,r0,SPR_EEAR_BASE
+
+ /*
+ * pmd = (pmd_t *)(current_pgd + pgd_index(daddr));
+ *
+ */
+ GET_CURRENT_PGD(r3,r4) // r3 is current_pgd, r5 is temp
+ l.srli r4,r2,0x18 // >> PAGE_SHIFT + (PAGE_SHIFT - 2)
+ l.slli r4,r4,0x2 // to get address << 2
+ l.add r3,r4,r3 // r4 is pgd_index(daddr)
+ /*
+ * if (pmd_none(*pmd))
+ * goto pmd_none:
+ */
+ tophys (r4,r3)
+ l.lwz r3,0x0(r4) // get *pmd value
+ l.sfne r3,r0
+ l.bnf i_pmd_none
+ l.addi r3,r0,0xffffe000 // PAGE_MASK
+
+i_pmd_good:
+ /*
+ * pte = *pte_offset(pmd, iaddr);
+ *
+ */
+ l.lwz r4,0x0(r4) // get **pmd value
+ l.and r4,r4,r3 // & PAGE_MASK
+ l.srli r2,r2,0xd // >> PAGE_SHIFT, r2 == EEAR
+ l.andi r3,r2,0x7ff // (1UL << PAGE_SHIFT - 2) - 1
+ l.slli r3,r3,0x2 // to get address << 2
+ l.add r3,r3,r4
+ l.lwz r3,0x0(r3) // this is pte at last
+ /*
+ * if (!pte_present(pte))
+ *
+ */
+ l.andi r4,r3,0x1
+ l.sfne r4,r0 // is pte present
+ l.bnf i_pte_not_present
+ l.addi r4,r0,0xffffe03a // PAGE_MASK | ITLB_UP_CONVERT_MASK
+ /*
+ * fill ITLB TR register
+ */
+ l.and r4,r3,r4 // apply the mask
+ l.andi r3,r3,0x7c0 // _PAGE_EXEC | _PAGE_SRE | _PAGE_SWE | _PAGE_URE | _PAGE_UWE
+ l.sfeq r3,r0
+ l.bf itlb_tr_fill //_workaround
+ // Determine number of IMMU sets
+ l.mfspr r2, r0, SPR_IMMUCFGR
+ l.andi r2, r2, SPR_IMMUCFGR_NTS
+ l.srli r2, r2, SPR_IMMUCFGR_NTS_OFF
+ l.ori r3, r0, 0x1
+ l.sll r3, r3, r2 // r3 = number IMMU sets IMMUCFGR
+ l.addi r2, r3, -1 // r2 = nsets mask
+ l.mfspr r3, r0, SPR_EEAR_BASE
+ l.srli r3, r3, 0xd // >> PAGE_SHIFT
+ l.and r2, r3, r2 // calc offset: & (NUM_TLB_ENTRIES-1)
+
+/*
+ * __PHX__ :: fixme
+ * we should not just blindly set executable flags,
+ * but it does help with ping. the clean way would be to find out
+ * (and fix it) why stack doesn't have execution permissions
+ */
+
+itlb_tr_fill_workaround:
+ l.ori r4,r4,0xc0 // | (SPR_ITLBTR_UXE | ITLBTR_SXE)
+itlb_tr_fill:
+ l.mtspr r2,r4,SPR_ITLBTR_BASE(0)
+ /*
+ * fill DTLB MR register
+ */
+ l.slli r3, r3, 0xd /* << PAGE_SHIFT => EA & PAGE_MASK */
+ l.ori r4,r3,0x1 // set hardware valid bit: ITBL_MR entry
+ l.mtspr r2,r4,SPR_ITLBMR_BASE(0)
+
+ EXCEPTION_LOAD_GPR2
+ EXCEPTION_LOAD_GPR3
+ EXCEPTION_LOAD_GPR4
+ l.rfe
+
+i_pmd_none:
+i_pte_not_present:
+ EXCEPTION_LOAD_GPR2
+ EXCEPTION_LOAD_GPR3
+ EXCEPTION_LOAD_GPR4
+ EXCEPTION_HANDLE(_itlb_miss_page_fault_handler)
+
+/* ==============================================[ boot tlb handlers ]=== */
+
+
+/* =================================================[ debugging aids ]=== */
+
+/*
+ * DESC: Prints ASCII character stored in r7
+ *
+ * PRMS: r7 - a 32-bit value with an ASCII character in the first byte
+ * position.
+ *
+ * PREQ: The UART at UART_BASE_ADD has to be initialized
+ *
+ * POST: internally used but restores:
+ * r4 - to store UART_BASE_ADD
+ * r5 - for loading OFF_TXFULL / THRE,TEMT
+ * r6 - for storing bitmask (SERIAL_8250)
+ */
+ENTRY(_emergency_putc)
+ EMERGENCY_PRINT_STORE_GPR4
+ EMERGENCY_PRINT_STORE_GPR5
+ EMERGENCY_PRINT_STORE_GPR6
+
+ l.movhi r4,hi(UART_BASE_ADD)
+ l.ori r4,r4,lo(UART_BASE_ADD)
+
+#if defined(CONFIG_SERIAL_LITEUART)
+ /* Check OFF_TXFULL status */
+1: l.lwz r5,4(r4)
+ l.andi r5,r5,0xff
+ l.sfnei r5,0
+ l.bf 1b
+ l.nop
+
+ /* Write character */
+ l.andi r7,r7,0xff
+ l.sw 0(r4),r7
+#elif defined(CONFIG_SERIAL_8250)
+ /* Check UART LSR THRE (hold) bit */
+ l.addi r6,r0,0x20
+1: l.lbz r5,5(r4)
+ l.andi r5,r5,0x20
+ l.sfeq r5,r6
+ l.bnf 1b
+ l.nop
+
+ /* Write character */
+ l.sb 0(r4),r7
+
+ /* Check UART LSR THRE|TEMT (hold, empty) bits */
+ l.addi r6,r0,0x60
+1: l.lbz r5,5(r4)
+ l.andi r5,r5,0x60
+ l.sfeq r5,r6
+ l.bnf 1b
+ l.nop
+#endif
+ EMERGENCY_PRINT_LOAD_GPR6
+ EMERGENCY_PRINT_LOAD_GPR5
+ EMERGENCY_PRINT_LOAD_GPR4
+ l.jr r9
+ l.nop
+
+/*
+ * DSCR: prints a string referenced by r3.
+ *
+ * PRMS: r3 - address of the first character of null
+ * terminated string to be printed
+ *
+ * PREQ: UART at UART_BASE_ADD has to be initialized
+ *
+ * POST: caller should be aware that r3, r9 are changed
+ */
+ENTRY(_emergency_print)
+ EMERGENCY_PRINT_STORE_GPR7
+ EMERGENCY_PRINT_STORE_GPR9
+
+ /* Load character to r7, check for null terminator */
+2: l.lbz r7,0(r3)
+ l.sfeqi r7,0x0
+ l.bf 9f
+ l.nop
+
+ l.jal _emergency_putc
+ l.nop
+
+ /* next character */
+ l.j 2b
+ l.addi r3,r3,0x1
+
+9:
+ EMERGENCY_PRINT_LOAD_GPR9
+ EMERGENCY_PRINT_LOAD_GPR7
+ l.jr r9
+ l.nop
+
+/*
+ * DSCR: prints a number in r3 in hex.
+ *
+ * PRMS: r3 - a 32-bit unsigned integer
+ *
+ * PREQ: UART at UART_BASE_ADD has to be initialized
+ *
+ * POST: caller should be aware that r3, r9 are changed
+ */
+ENTRY(_emergency_print_nr)
+ EMERGENCY_PRINT_STORE_GPR7
+ EMERGENCY_PRINT_STORE_GPR8
+ EMERGENCY_PRINT_STORE_GPR9
+
+ l.addi r8,r0,32 // shift register
+
+1: /* remove leading zeros */
+ l.addi r8,r8,-0x4
+ l.srl r7,r3,r8
+ l.andi r7,r7,0xf
+
+ /* don't skip the last zero if number == 0x0 */
+ l.sfeqi r8,0x4
+ l.bf 2f
+ l.nop
+
+ l.sfeq r7,r0
+ l.bf 1b
+ l.nop
+
+2:
+ l.srl r7,r3,r8
+
+ l.andi r7,r7,0xf
+ l.sflts r8,r0
+ l.bf 9f
+
+ /* Numbers greater than 9 translate to a-f */
+ l.sfgtui r7,0x9
+ l.bnf 8f
+ l.nop
+ l.addi r7,r7,0x27
+
+ /* Convert to ascii and output character */
+8: l.jal _emergency_putc
+ l.addi r7,r7,0x30
+
+ /* next character */
+ l.j 2b
+ l.addi r8,r8,-0x4
+
+9:
+ EMERGENCY_PRINT_LOAD_GPR9
+ EMERGENCY_PRINT_LOAD_GPR8
+ EMERGENCY_PRINT_LOAD_GPR7
+ l.jr r9
+ l.nop
+
+/*
+ * This should be used for debugging only.
+ * It messes up the Linux early serial output
+ * somehow, so use it sparingly and essentially
+ * only if you need to debug something that goes wrong
+ * before Linux gets the early serial going.
+ *
+ * Furthermore, you'll have to make sure you set the
+ * UART_DEVISOR correctly according to the system
+ * clock rate.
+ *
+ *
+ */
+
+
+
+#define SYS_CLK 20000000
+//#define SYS_CLK 1843200
+#define OR32_CONSOLE_BAUD 115200
+#define UART_DIVISOR SYS_CLK/(16*OR32_CONSOLE_BAUD)
+
+ENTRY(_early_uart_init)
+ l.movhi r3,hi(UART_BASE_ADD)
+ l.ori r3,r3,lo(UART_BASE_ADD)
+
+#if defined(CONFIG_SERIAL_8250)
+ l.addi r4,r0,0x7
+ l.sb 0x2(r3),r4
+
+ l.addi r4,r0,0x0
+ l.sb 0x1(r3),r4
+
+ l.addi r4,r0,0x3
+ l.sb 0x3(r3),r4
+
+ l.lbz r5,3(r3)
+ l.ori r4,r5,0x80
+ l.sb 0x3(r3),r4
+ l.addi r4,r0,((UART_DIVISOR>>8) & 0x000000ff)
+ l.sb UART_DLM(r3),r4
+ l.addi r4,r0,((UART_DIVISOR) & 0x000000ff)
+ l.sb UART_DLL(r3),r4
+ l.sb 0x3(r3),r5
+#endif
+
+ l.jr r9
+ l.nop
+
+ .align 0x1000
+ .global _secondary_evbar
+_secondary_evbar:
+
+ .space 0x800
+ /* Just disable interrupts and Return */
+ l.ori r3,r0,SPR_SR_SM
+ l.mtspr r0,r3,SPR_ESR_BASE
+ l.rfe
+
+
+ .section .rodata
+_string_unhandled_exception:
+ .string "\r\nRunarunaround: Unhandled exception 0x\0"
+
+_string_epc_prefix:
+ .string ": EPC=0x\0"
+
+_string_nl:
+ .string "\r\n\0"
+
+
+/* ========================================[ page aligned structures ]=== */
+
+/*
+ * .data section should be page aligned
+ * (look into arch/openrisc/kernel/vmlinux.lds.S)
+ */
+ .section .data,"aw"
+ .align 8192
+ .global empty_zero_page
+empty_zero_page:
+ .space 8192
+
+ .global swapper_pg_dir
+swapper_pg_dir:
+ .space 8192
+
+ .global _unhandled_stack
+_unhandled_stack:
+ .space 8192
+_unhandled_stack_top:
+
+/* ============================================================[ EOF ]=== */
diff --git a/arch/openrisc/kernel/irq.c b/arch/openrisc/kernel/irq.c
new file mode 100644
index 0000000000..f38e10962a
--- /dev/null
+++ b/arch/openrisc/kernel/irq.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC irq.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/ftrace.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/export.h>
+#include <linux/irqflags.h>
+
+/* read interrupt enabled status */
+unsigned long arch_local_save_flags(void)
+{
+ return mfspr(SPR_SR) & (SPR_SR_IEE|SPR_SR_TEE);
+}
+EXPORT_SYMBOL(arch_local_save_flags);
+
+/* set interrupt enabled status */
+void arch_local_irq_restore(unsigned long flags)
+{
+ mtspr(SPR_SR, ((mfspr(SPR_SR) & ~(SPR_SR_IEE|SPR_SR_TEE)) | flags));
+}
+EXPORT_SYMBOL(arch_local_irq_restore);
+
+void __init init_IRQ(void)
+{
+ irqchip_init();
+}
diff --git a/arch/openrisc/kernel/module.c b/arch/openrisc/kernel/module.c
new file mode 100644
index 0000000000..532013f523
--- /dev/null
+++ b/arch/openrisc/kernel/module.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC module.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+
+int apply_relocate_add(Elf32_Shdr *sechdrs,
+ const char *strtab,
+ unsigned int symindex,
+ unsigned int relsec,
+ struct module *me)
+{
+ unsigned int i;
+ Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
+ Elf32_Sym *sym;
+ uint32_t *location;
+ uint32_t value;
+
+ pr_debug("Applying relocate section %u to %u\n", relsec,
+ sechdrs[relsec].sh_info);
+ for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+ /* This is where to make the change */
+ location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ + rel[i].r_offset;
+
+ /* This is the symbol it is referring to. Note that all
+ undefined symbols have been resolved. */
+ sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+ + ELF32_R_SYM(rel[i].r_info);
+ value = sym->st_value + rel[i].r_addend;
+
+ switch (ELF32_R_TYPE(rel[i].r_info)) {
+ case R_OR32_32:
+ *location = value;
+ break;
+ case R_OR32_CONST:
+ *((uint16_t *)location + 1) = value;
+ break;
+ case R_OR32_CONSTH:
+ *((uint16_t *)location + 1) = value >> 16;
+ break;
+ case R_OR32_JUMPTARG:
+ value -= (uint32_t)location;
+ value >>= 2;
+ value &= 0x03ffffff;
+ value |= *location & 0xfc000000;
+ *location = value;
+ break;
+ default:
+ pr_err("module %s: Unknown relocation: %u\n",
+ me->name, ELF32_R_TYPE(rel[i].r_info));
+ break;
+ }
+ }
+
+ return 0;
+}
diff --git a/arch/openrisc/kernel/or32_ksyms.c b/arch/openrisc/kernel/or32_ksyms.c
new file mode 100644
index 0000000000..212e5f8500
--- /dev/null
+++ b/arch/openrisc/kernel/or32_ksyms.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC or32_ksyms.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/export.h>
+#include <linux/elfcore.h>
+#include <linux/sched.h>
+#include <linux/in6.h>
+#include <linux/interrupt.h>
+#include <linux/vmalloc.h>
+#include <linux/semaphore.h>
+#include <linux/pgtable.h>
+
+#include <asm/processor.h>
+#include <linux/uaccess.h>
+#include <asm/checksum.h>
+#include <asm/io.h>
+#include <asm/hardirq.h>
+#include <asm/delay.h>
+
+#define DECLARE_EXPORT(name) extern void name(void); EXPORT_SYMBOL(name)
+
+/* compiler generated symbols */
+DECLARE_EXPORT(__udivsi3);
+DECLARE_EXPORT(__divsi3);
+DECLARE_EXPORT(__umodsi3);
+DECLARE_EXPORT(__modsi3);
+DECLARE_EXPORT(__muldi3);
+DECLARE_EXPORT(__ashrdi3);
+DECLARE_EXPORT(__ashldi3);
+DECLARE_EXPORT(__lshrdi3);
+DECLARE_EXPORT(__ucmpdi2);
+
+EXPORT_SYMBOL(empty_zero_page);
+EXPORT_SYMBOL(__copy_tofrom_user);
+EXPORT_SYMBOL(__clear_user);
+EXPORT_SYMBOL(memset);
diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c
new file mode 100644
index 0000000000..86e02929f3
--- /dev/null
+++ b/arch/openrisc/kernel/process.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC process.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * This file handles the architecture-dependent parts of process handling...
+ */
+
+#define __KERNEL_SYSCALLS__
+#include <linux/cpu.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task.h>
+#include <linux/sched/task_stack.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/elfcore.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/init_task.h>
+#include <linux/mqueue.h>
+#include <linux/fs.h>
+#include <linux/reboot.h>
+
+#include <linux/uaccess.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/spr_defs.h>
+#include <asm/switch_to.h>
+
+#include <linux/smp.h>
+
+/*
+ * Pointer to Current thread info structure.
+ *
+ * Used at user space -> kernel transitions.
+ */
+struct thread_info *current_thread_info_set[NR_CPUS] = { &init_thread_info, };
+
+void machine_restart(char *cmd)
+{
+ do_kernel_restart(cmd);
+
+ __asm__("l.nop 13");
+
+ /* Give a grace period for failure to restart of 1s */
+ mdelay(1000);
+
+ /* Whoops - the platform was unable to reboot. Tell the user! */
+ pr_emerg("Reboot failed -- System halted\n");
+ while (1);
+}
+
+/*
+ * This is used if pm_power_off has not been set by a power management
+ * driver, in this case we can assume we are on a simulator. On
+ * OpenRISC simulators l.nop 1 will trigger the simulator exit.
+ */
+static void default_power_off(void)
+{
+ __asm__("l.nop 1");
+}
+
+/*
+ * Similar to machine_power_off, but don't shut off power. Add code
+ * here to freeze the system for e.g. post-mortem debug purpose when
+ * possible. This halt has nothing to do with the idle halt.
+ */
+void machine_halt(void)
+{
+ printk(KERN_INFO "*** MACHINE HALT ***\n");
+ __asm__("l.nop 1");
+}
+
+/* If or when software power-off is implemented, add code here. */
+void machine_power_off(void)
+{
+ printk(KERN_INFO "*** MACHINE POWER OFF ***\n");
+ if (pm_power_off != NULL)
+ pm_power_off();
+ else
+ default_power_off();
+}
+
+/*
+ * Send the doze signal to the cpu if available.
+ * Make sure, that all interrupts are enabled
+ */
+void arch_cpu_idle(void)
+{
+ raw_local_irq_enable();
+ if (mfspr(SPR_UPR) & SPR_UPR_PMP)
+ mtspr(SPR_PMR, mfspr(SPR_PMR) | SPR_PMR_DME);
+ raw_local_irq_disable();
+}
+
+void (*pm_power_off)(void) = NULL;
+EXPORT_SYMBOL(pm_power_off);
+
+/*
+ * When a process does an "exec", machine state like FPU and debug
+ * registers need to be reset. This is a hook function for that.
+ * Currently we don't have any such state to reset, so this is empty.
+ */
+void flush_thread(void)
+{
+}
+
+void show_regs(struct pt_regs *regs)
+{
+ show_regs_print_info(KERN_DEFAULT);
+ /* __PHX__ cleanup this mess */
+ show_registers(regs);
+}
+
+/*
+ * Copy the thread-specific (arch specific) info from the current
+ * process to the new one p
+ */
+extern asmlinkage void ret_from_fork(void);
+
+/*
+ * copy_thread
+ * @clone_flags: flags
+ * @usp: user stack pointer or fn for kernel thread
+ * @arg: arg to fn for kernel thread; always NULL for userspace thread
+ * @p: the newly created task
+ * @tls: the Thread Local Storage pointer for the new process
+ *
+ * At the top of a newly initialized kernel stack are two stacked pt_reg
+ * structures. The first (topmost) is the userspace context of the thread.
+ * The second is the kernelspace context of the thread.
+ *
+ * A kernel thread will not be returning to userspace, so the topmost pt_regs
+ * struct can be uninitialized; it _does_ need to exist, though, because
+ * a kernel thread can become a userspace thread by doing a kernel_execve, in
+ * which case the topmost context will be initialized and used for 'returning'
+ * to userspace.
+ *
+ * The second pt_reg struct needs to be initialized to 'return' to
+ * ret_from_fork. A kernel thread will need to set r20 to the address of
+ * a function to call into (with arg in r22); userspace threads need to set
+ * r20 to NULL in which case ret_from_fork will just continue a return to
+ * userspace.
+ *
+ * A kernel thread 'fn' may return; this is effectively what happens when
+ * kernel_execve is called. In that case, the userspace pt_regs must have
+ * been initialized (which kernel_execve takes care of, see start_thread
+ * below); ret_from_fork will then continue its execution causing the
+ * 'kernel thread' to return to userspace as a userspace thread.
+ */
+
+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 *userregs;
+ struct pt_regs *kregs;
+ unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
+ unsigned long top_of_kernel_stack;
+
+ top_of_kernel_stack = sp;
+
+ /* Locate userspace context on stack... */
+ sp -= STACK_FRAME_OVERHEAD; /* redzone */
+ sp -= sizeof(struct pt_regs);
+ userregs = (struct pt_regs *) sp;
+
+ /* ...and kernel context */
+ sp -= STACK_FRAME_OVERHEAD; /* redzone */
+ sp -= sizeof(struct pt_regs);
+ kregs = (struct pt_regs *)sp;
+
+ if (unlikely(args->fn)) {
+ memset(kregs, 0, sizeof(struct pt_regs));
+ kregs->gpr[20] = (unsigned long)args->fn;
+ kregs->gpr[22] = (unsigned long)args->fn_arg;
+ } else {
+ *userregs = *current_pt_regs();
+
+ if (usp)
+ userregs->sp = usp;
+
+ /*
+ * For CLONE_SETTLS set "tp" (r10) to the TLS pointer.
+ */
+ if (clone_flags & CLONE_SETTLS)
+ userregs->gpr[10] = tls;
+
+ userregs->gpr[11] = 0; /* Result from fork() */
+
+ kregs->gpr[20] = 0; /* Userspace thread */
+ }
+
+ /*
+ * _switch wants the kernel stack page in pt_regs->sp so that it
+ * can restore it to thread_info->ksp... see _switch for details.
+ */
+ kregs->sp = top_of_kernel_stack;
+ kregs->gpr[9] = (unsigned long)ret_from_fork;
+
+ task_thread_info(p)->ksp = (unsigned long)kregs;
+
+ return 0;
+}
+
+/*
+ * Set up a thread for executing a new program
+ */
+void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
+{
+ unsigned long sr = mfspr(SPR_SR) & ~SPR_SR_SM;
+
+ memset(regs, 0, sizeof(struct pt_regs));
+
+ regs->pc = pc;
+ regs->sr = sr;
+ regs->sp = sp;
+}
+
+extern struct thread_info *_switch(struct thread_info *old_ti,
+ struct thread_info *new_ti);
+extern int lwa_flag;
+
+struct task_struct *__switch_to(struct task_struct *old,
+ struct task_struct *new)
+{
+ struct task_struct *last;
+ struct thread_info *new_ti, *old_ti;
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ /* current_set is an array of saved current pointers
+ * (one for each cpu). we need them at user->kernel transition,
+ * while we save them at kernel->user transition
+ */
+ new_ti = new->stack;
+ old_ti = old->stack;
+
+ lwa_flag = 0;
+
+ current_thread_info_set[smp_processor_id()] = new_ti;
+ last = (_switch(old_ti, new_ti))->task;
+
+ local_irq_restore(flags);
+
+ return last;
+}
+
+/*
+ * Write out registers in core dump format, as defined by the
+ * struct user_regs_struct
+ */
+void dump_elf_thread(elf_greg_t *dest, struct pt_regs* regs)
+{
+ dest[0] = 0; /* r0 */
+ memcpy(dest+1, regs->gpr+1, 31*sizeof(unsigned long));
+ dest[32] = regs->pc;
+ dest[33] = regs->sr;
+ dest[34] = 0;
+ dest[35] = 0;
+}
+
+unsigned long __get_wchan(struct task_struct *p)
+{
+ /* TODO */
+
+ return 0;
+}
diff --git a/arch/openrisc/kernel/prom.c b/arch/openrisc/kernel/prom.c
new file mode 100644
index 0000000000..19e6008bf1
--- /dev/null
+++ b/arch/openrisc/kernel/prom.c
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC prom.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * Architecture specific procedures for creating, accessing and
+ * interpreting the device tree.
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/memblock.h>
+#include <linux/of_fdt.h>
+
+#include <asm/page.h>
+
+void __init early_init_devtree(void *params)
+{
+ early_init_dt_scan(params);
+ memblock_allow_resize();
+}
diff --git a/arch/openrisc/kernel/ptrace.c b/arch/openrisc/kernel/ptrace.c
new file mode 100644
index 0000000000..1eeac3b62e
--- /dev/null
+++ b/arch/openrisc/kernel/ptrace.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC ptrace.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2005 Gyorgy Jeney <nog@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/string.h>
+
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/audit.h>
+#include <linux/regset.h>
+#include <linux/elf.h>
+
+#include <asm/thread_info.h>
+#include <asm/page.h>
+
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs);
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs);
+
+/*
+ * Copy the thread state to a regset that can be interpreted by userspace.
+ *
+ * It doesn't matter what our internal pt_regs structure looks like. The
+ * important thing is that we export a consistent view of the thread state
+ * to userspace. As such, we need to make sure that the regset remains
+ * ABI compatible as defined by the struct user_regs_struct:
+ *
+ * (Each item is a 32-bit word)
+ * r0 = 0 (exported for clarity)
+ * 31 GPRS r1-r31
+ * PC (Program counter)
+ * SR (Supervision register)
+ */
+static int genregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ const struct pt_regs *regs = task_pt_regs(target);
+
+ /* r0 */
+ membuf_zero(&to, 4);
+ membuf_write(&to, regs->gpr + 1, 31 * 4);
+ membuf_store(&to, regs->pc);
+ return membuf_store(&to, regs->sr);
+}
+
+/*
+ * Set the thread state from a regset passed in via ptrace
+ */
+static int genregs_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user * ubuf)
+{
+ struct pt_regs *regs = task_pt_regs(target);
+ int ret;
+
+ /* ignore r0 */
+ user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4);
+ /* r1 - r31 */
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ regs->gpr+1, 4, 4*32);
+ /* PC */
+ if (!ret)
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->pc, 4*32, 4*33);
+ /*
+ * Skip SR and padding... userspace isn't allowed to changes bits in
+ * the Supervision register
+ */
+ if (!ret)
+ user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 4*33, -1);
+
+ return ret;
+}
+
+/*
+ * As OpenRISC shares GPRs and floating point registers we don't need to export
+ * the floating point registers again. So here we only export the fpcsr special
+ * purpose register.
+ */
+static int fpregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ const struct pt_regs *regs = task_pt_regs(target);
+
+ return membuf_store(&to, regs->fpcsr);
+}
+
+static int fpregs_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ struct pt_regs *regs = task_pt_regs(target);
+ int ret;
+
+ /* FPCSR */
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->fpcsr, 0, 4);
+ return ret;
+}
+
+/*
+ * Define the register sets available on OpenRISC under Linux
+ */
+enum or1k_regset {
+ REGSET_GENERAL,
+ REGSET_FPU,
+};
+
+static const struct user_regset or1k_regsets[] = {
+ [REGSET_GENERAL] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(long),
+ .align = sizeof(long),
+ .regset_get = genregs_get,
+ .set = genregs_set,
+ },
+ [REGSET_FPU] = {
+ .core_note_type = NT_PRFPREG,
+ .n = sizeof(struct __or1k_fpu_state) / sizeof(long),
+ .size = sizeof(long),
+ .align = sizeof(long),
+ .regset_get = fpregs_get,
+ .set = fpregs_set,
+ },
+};
+
+static const struct user_regset_view user_or1k_native_view = {
+ .name = "or1k",
+ .e_machine = EM_OPENRISC,
+ .regsets = or1k_regsets,
+ .n = ARRAY_SIZE(or1k_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &user_or1k_native_view;
+}
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure the single step bit is not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ pr_debug("ptrace_disable(): TODO\n");
+
+ user_disable_single_step(child);
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+}
+
+long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
+ unsigned long data)
+{
+ int ret;
+
+ switch (request) {
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+/*
+ * Notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
+{
+ long ret = 0;
+
+ if (test_thread_flag(TIF_SYSCALL_TRACE) &&
+ ptrace_report_syscall_entry(regs))
+ /*
+ * Tracing decided this syscall should not happen.
+ * We'll return a bogus call number to get an ENOSYS
+ * error, but leave the original number in <something>.
+ */
+ ret = -1L;
+
+ audit_syscall_entry(regs->gpr[11], regs->gpr[3], regs->gpr[4],
+ regs->gpr[5], regs->gpr[6]);
+
+ return ret ? : regs->gpr[11];
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+ int step;
+
+ audit_syscall_exit(regs);
+
+ step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ ptrace_report_syscall_exit(regs, step);
+}
diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
new file mode 100644
index 0000000000..9cf7fb6044
--- /dev/null
+++ b/arch/openrisc/kernel/setup.c
@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC setup.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * This file handles the architecture-dependent parts of initialization
+ */
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/memblock.h>
+#include <linux/seq_file.h>
+#include <linux/serial.h>
+#include <linux/initrd.h>
+#include <linux/of_fdt.h>
+#include <linux/of.h>
+#include <linux/device.h>
+
+#include <asm/sections.h>
+#include <asm/types.h>
+#include <asm/setup.h>
+#include <asm/io.h>
+#include <asm/cpuinfo.h>
+#include <asm/delay.h>
+
+#include "vmlinux.h"
+
+static void __init setup_memory(void)
+{
+ unsigned long ram_start_pfn;
+ unsigned long ram_end_pfn;
+ phys_addr_t memory_start, memory_end;
+
+ memory_end = memory_start = 0;
+
+ /* Find main memory where is the kernel, we assume its the only one */
+ memory_start = memblock_start_of_DRAM();
+ memory_end = memblock_end_of_DRAM();
+
+ if (!memory_end) {
+ panic("No memory!");
+ }
+
+ ram_start_pfn = PFN_UP(memory_start);
+ ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
+
+ /* setup bootmem globals (we use no_bootmem, but mm still depends on this) */
+ min_low_pfn = ram_start_pfn;
+ max_low_pfn = ram_end_pfn;
+ max_pfn = ram_end_pfn;
+
+ /*
+ * initialize the boot-time allocator (with low memory only).
+ *
+ * This makes the memory from the end of the kernel to the end of
+ * RAM usable.
+ */
+ memblock_reserve(__pa(_stext), _end - _stext);
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ /* Then reserve the initrd, if any */
+ if (initrd_start && (initrd_end > initrd_start)) {
+ unsigned long aligned_start = ALIGN_DOWN(initrd_start, PAGE_SIZE);
+ unsigned long aligned_end = ALIGN(initrd_end, PAGE_SIZE);
+
+ memblock_reserve(__pa(aligned_start), aligned_end - aligned_start);
+ }
+#endif /* CONFIG_BLK_DEV_INITRD */
+
+ early_init_fdt_reserve_self();
+ early_init_fdt_scan_reserved_mem();
+
+ memblock_dump_all();
+}
+
+struct cpuinfo_or1k cpuinfo_or1k[NR_CPUS];
+
+static void print_cpuinfo(void)
+{
+ unsigned long upr = mfspr(SPR_UPR);
+ unsigned long vr = mfspr(SPR_VR);
+ unsigned int version;
+ unsigned int revision;
+ struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
+
+ version = (vr & SPR_VR_VER) >> 24;
+ revision = (vr & SPR_VR_REV);
+
+ printk(KERN_INFO "CPU: OpenRISC-%x (revision %d) @%d MHz\n",
+ version, revision, cpuinfo->clock_frequency / 1000000);
+
+ if (!(upr & SPR_UPR_UP)) {
+ printk(KERN_INFO
+ "-- no UPR register... unable to detect configuration\n");
+ return;
+ }
+
+ if (upr & SPR_UPR_DCP)
+ printk(KERN_INFO
+ "-- dcache: %4d bytes total, %2d bytes/line, %d way(s)\n",
+ cpuinfo->dcache_size, cpuinfo->dcache_block_size,
+ cpuinfo->dcache_ways);
+ else
+ printk(KERN_INFO "-- dcache disabled\n");
+ if (upr & SPR_UPR_ICP)
+ printk(KERN_INFO
+ "-- icache: %4d bytes total, %2d bytes/line, %d way(s)\n",
+ cpuinfo->icache_size, cpuinfo->icache_block_size,
+ cpuinfo->icache_ways);
+ else
+ printk(KERN_INFO "-- icache disabled\n");
+
+ if (upr & SPR_UPR_DMP)
+ printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n",
+ 1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
+ 1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
+ if (upr & SPR_UPR_IMP)
+ printk(KERN_INFO "-- immu: %4d entries, %lu way(s)\n",
+ 1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
+ 1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
+
+ printk(KERN_INFO "-- additional features:\n");
+ if (upr & SPR_UPR_DUP)
+ printk(KERN_INFO "-- debug unit\n");
+ if (upr & SPR_UPR_PCUP)
+ printk(KERN_INFO "-- performance counters\n");
+ if (upr & SPR_UPR_PMP)
+ printk(KERN_INFO "-- power management\n");
+ if (upr & SPR_UPR_PICP)
+ printk(KERN_INFO "-- PIC\n");
+ if (upr & SPR_UPR_TTP)
+ printk(KERN_INFO "-- timer\n");
+ if (upr & SPR_UPR_CUP)
+ printk(KERN_INFO "-- custom unit(s)\n");
+}
+
+void __init setup_cpuinfo(void)
+{
+ struct device_node *cpu;
+ unsigned long iccfgr, dccfgr;
+ unsigned long cache_set_size;
+ int cpu_id = smp_processor_id();
+ struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[cpu_id];
+
+ cpu = of_get_cpu_node(cpu_id, NULL);
+ if (!cpu)
+ panic("Couldn't find CPU%d in device tree...\n", cpu_id);
+
+ iccfgr = mfspr(SPR_ICCFGR);
+ cpuinfo->icache_ways = 1 << (iccfgr & SPR_ICCFGR_NCW);
+ cache_set_size = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3);
+ cpuinfo->icache_block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7);
+ cpuinfo->icache_size =
+ cache_set_size * cpuinfo->icache_ways * cpuinfo->icache_block_size;
+
+ dccfgr = mfspr(SPR_DCCFGR);
+ cpuinfo->dcache_ways = 1 << (dccfgr & SPR_DCCFGR_NCW);
+ cache_set_size = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3);
+ cpuinfo->dcache_block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7);
+ cpuinfo->dcache_size =
+ cache_set_size * cpuinfo->dcache_ways * cpuinfo->dcache_block_size;
+
+ if (of_property_read_u32(cpu, "clock-frequency",
+ &cpuinfo->clock_frequency)) {
+ printk(KERN_WARNING
+ "Device tree missing CPU 'clock-frequency' parameter."
+ "Assuming frequency 25MHZ"
+ "This is probably not what you want.");
+ }
+
+ cpuinfo->coreid = mfspr(SPR_COREID);
+
+ of_node_put(cpu);
+
+ print_cpuinfo();
+}
+
+/**
+ * or1k_early_setup
+ * @fdt: pointer to the start of the device tree in memory or NULL
+ *
+ * Handles the pointer to the device tree that this kernel is to use
+ * for establishing the available platform devices.
+ *
+ * Falls back on built-in device tree in case null pointer is passed.
+ */
+
+void __init or1k_early_setup(void *fdt)
+{
+ if (fdt)
+ pr_info("FDT at %p\n", fdt);
+ else {
+ fdt = __dtb_start;
+ pr_info("Compiled-in FDT at %p\n", fdt);
+ }
+ early_init_devtree(fdt);
+}
+
+static inline unsigned long extract_value_bits(unsigned long reg,
+ short bit_nr, short width)
+{
+ return (reg >> bit_nr) & (0 << width);
+}
+
+static inline unsigned long extract_value(unsigned long reg, unsigned long mask)
+{
+ while (!(mask & 0x1)) {
+ reg = reg >> 1;
+ mask = mask >> 1;
+ }
+ return mask & reg;
+}
+
+/*
+ * calibrate_delay
+ *
+ * Lightweight calibrate_delay implementation that calculates loops_per_jiffy
+ * from the clock frequency passed in via the device tree
+ *
+ */
+
+void calibrate_delay(void)
+{
+ const int *val;
+ struct device_node *cpu = of_get_cpu_node(smp_processor_id(), NULL);
+
+ val = of_get_property(cpu, "clock-frequency", NULL);
+ if (!val)
+ panic("no cpu 'clock-frequency' parameter in device tree");
+ loops_per_jiffy = *val / HZ;
+ pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
+ loops_per_jiffy / (500000 / HZ),
+ (loops_per_jiffy / (5000 / HZ)) % 100, loops_per_jiffy);
+
+ of_node_put(cpu);
+}
+
+void __init setup_arch(char **cmdline_p)
+{
+ unflatten_and_copy_device_tree();
+
+ setup_cpuinfo();
+
+#ifdef CONFIG_SMP
+ smp_init_cpus();
+#endif
+
+ /* process 1's initial memory region is the kernel code/data */
+ setup_initial_init_mm(_stext, _etext, _edata, _end);
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ if (initrd_start == initrd_end) {
+ printk(KERN_INFO "Initial ramdisk not found\n");
+ initrd_start = 0;
+ initrd_end = 0;
+ } else {
+ printk(KERN_INFO "Initial ramdisk at: 0x%p (%lu bytes)\n",
+ (void *)(initrd_start), initrd_end - initrd_start);
+ initrd_below_start_ok = 1;
+ }
+#endif
+
+ /* setup memblock allocator */
+ setup_memory();
+
+ /* paging_init() sets up the MMU and marks all pages as reserved */
+ paging_init();
+
+ *cmdline_p = boot_command_line;
+
+ printk(KERN_INFO "OpenRISC Linux -- http://openrisc.io\n");
+}
+
+static int show_cpuinfo(struct seq_file *m, void *v)
+{
+ unsigned int vr, cpucfgr;
+ unsigned int avr;
+ unsigned int version;
+ struct cpuinfo_or1k *cpuinfo = v;
+
+ vr = mfspr(SPR_VR);
+ cpucfgr = mfspr(SPR_CPUCFGR);
+
+#ifdef CONFIG_SMP
+ seq_printf(m, "processor\t\t: %d\n", cpuinfo->coreid);
+#endif
+ if (vr & SPR_VR_UVRP) {
+ vr = mfspr(SPR_VR2);
+ version = vr & SPR_VR2_VER;
+ avr = mfspr(SPR_AVR);
+ seq_printf(m, "cpu architecture\t: "
+ "OpenRISC 1000 (%d.%d-rev%d)\n",
+ (avr >> 24) & 0xff,
+ (avr >> 16) & 0xff,
+ (avr >> 8) & 0xff);
+ seq_printf(m, "cpu implementation id\t: 0x%x\n",
+ (vr & SPR_VR2_CPUID) >> 24);
+ seq_printf(m, "cpu version\t\t: 0x%x\n", version);
+ } else {
+ version = (vr & SPR_VR_VER) >> 24;
+ seq_printf(m, "cpu\t\t\t: OpenRISC-%x\n", version);
+ seq_printf(m, "revision\t\t: %d\n", vr & SPR_VR_REV);
+ }
+ seq_printf(m, "frequency\t\t: %ld\n", loops_per_jiffy * HZ);
+ seq_printf(m, "dcache size\t\t: %d bytes\n", cpuinfo->dcache_size);
+ seq_printf(m, "dcache block size\t: %d bytes\n",
+ cpuinfo->dcache_block_size);
+ seq_printf(m, "dcache ways\t\t: %d\n", cpuinfo->dcache_ways);
+ seq_printf(m, "icache size\t\t: %d bytes\n", cpuinfo->icache_size);
+ seq_printf(m, "icache block size\t: %d bytes\n",
+ cpuinfo->icache_block_size);
+ seq_printf(m, "icache ways\t\t: %d\n", cpuinfo->icache_ways);
+ seq_printf(m, "immu\t\t\t: %d entries, %lu ways\n",
+ 1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2),
+ 1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW));
+ seq_printf(m, "dmmu\t\t\t: %d entries, %lu ways\n",
+ 1 << ((mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTS) >> 2),
+ 1 + (mfspr(SPR_IMMUCFGR) & SPR_IMMUCFGR_NTW));
+ seq_printf(m, "bogomips\t\t: %lu.%02lu\n",
+ (loops_per_jiffy * HZ) / 500000,
+ ((loops_per_jiffy * HZ) / 5000) % 100);
+
+ seq_puts(m, "features\t\t: ");
+ seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OB32S ? "orbis32" : "");
+ seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OB64S ? "orbis64" : "");
+ seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OF32S ? "orfpx32" : "");
+ seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OF64S ? "orfpx64" : "");
+ seq_printf(m, "%s ", cpucfgr & SPR_CPUCFGR_OV64S ? "orvdx64" : "");
+ seq_puts(m, "\n");
+
+ seq_puts(m, "\n");
+
+ return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+ *pos = cpumask_next(*pos - 1, cpu_online_mask);
+ if ((*pos) < nr_cpu_ids)
+ return &cpuinfo_or1k[*pos];
+ return 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,
+};
diff --git a/arch/openrisc/kernel/signal.c b/arch/openrisc/kernel/signal.c
new file mode 100644
index 0000000000..e2f21a5d8a
--- /dev/null
+++ b/arch/openrisc/kernel/signal.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC signal.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/stddef.h>
+#include <linux/resume_user_mode.h>
+
+#include <asm/processor.h>
+#include <asm/syscall.h>
+#include <asm/ucontext.h>
+#include <linux/uaccess.h>
+
+struct rt_sigframe {
+ struct siginfo info;
+ struct ucontext uc;
+ unsigned char retcode[16]; /* trampoline code */
+};
+
+asmlinkage long _sys_rt_sigreturn(struct pt_regs *regs);
+
+asmlinkage int do_work_pending(struct pt_regs *regs, unsigned int thread_flags,
+ int syscall);
+
+static int restore_sigcontext(struct pt_regs *regs,
+ struct sigcontext __user *sc)
+{
+ int err = 0;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ /*
+ * Restore the regs from &sc->regs.
+ * (sc is already checked since the sigframe was
+ * checked in sys_sigreturn previously)
+ */
+ err |= __copy_from_user(regs, sc->regs.gpr, 32 * sizeof(unsigned long));
+ err |= __copy_from_user(&regs->pc, &sc->regs.pc, sizeof(unsigned long));
+ err |= __copy_from_user(&regs->sr, &sc->regs.sr, sizeof(unsigned long));
+ err |= __copy_from_user(&regs->fpcsr, &sc->fpcsr, sizeof(unsigned long));
+
+ /* make sure the SM-bit is cleared so user-mode cannot fool us */
+ regs->sr &= ~SPR_SR_SM;
+
+ regs->orig_gpr11 = -1; /* Avoid syscall restart checks */
+
+ /* TODO: the other ports use regs->orig_XX to disable syscall checks
+ * after this completes, but we don't use that mechanism. maybe we can
+ * use it now ?
+ */
+
+ return err;
+}
+
+asmlinkage long _sys_rt_sigreturn(struct pt_regs *regs)
+{
+ struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->sp;
+ sigset_t set;
+
+ /*
+ * Since we stacked the signal on a dword boundary,
+ * then frame should be dword aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (((unsigned long)frame) & 3)
+ goto badframe;
+
+ if (!access_ok(frame, sizeof(*frame)))
+ goto badframe;
+ if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->gpr[11];
+
+badframe:
+ force_sig(SIGSEGV);
+ return 0;
+}
+
+/*
+ * Set up a signal frame.
+ */
+
+static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
+{
+ int err = 0;
+
+ /* copy the regs */
+ /* There should be no need to save callee-saved registers here...
+ * ...but we save them anyway. Revisit this
+ */
+ err |= __copy_to_user(sc->regs.gpr, regs, 32 * sizeof(unsigned long));
+ err |= __copy_to_user(&sc->regs.pc, &regs->pc, sizeof(unsigned long));
+ err |= __copy_to_user(&sc->regs.sr, &regs->sr, sizeof(unsigned long));
+ err |= __copy_to_user(&sc->fpcsr, &regs->fpcsr, sizeof(unsigned long));
+
+ return err;
+}
+
+static inline unsigned long align_sigframe(unsigned long sp)
+{
+ return sp & ~3UL;
+}
+
+/*
+ * Work out where the signal frame should go. It's either on the user stack
+ * or the alternate stack.
+ */
+
+static inline void __user *get_sigframe(struct ksignal *ksig,
+ struct pt_regs *regs, size_t frame_size)
+{
+ unsigned long sp = regs->sp;
+
+ /* redzone */
+ sp -= STACK_FRAME_OVERHEAD;
+ sp = sigsp(sp, ksig);
+ sp = align_sigframe(sp - frame_size);
+
+ return (void __user *)sp;
+}
+
+/* grab and setup a signal frame.
+ *
+ * basically we stack a lot of state info, and arrange for the
+ * user-mode program to return to the kernel using either a
+ * trampoline which performs the syscall sigreturn, or a provided
+ * user-mode trampoline.
+ */
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+ struct pt_regs *regs)
+{
+ struct rt_sigframe __user *frame;
+ unsigned long return_ip;
+ int err = 0;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame));
+
+ if (!access_ok(frame, sizeof(*frame)))
+ return -EFAULT;
+
+ /* Create siginfo. */
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+ err |= copy_siginfo_to_user(&frame->info, &ksig->info);
+
+ /* Create the ucontext. */
+ err |= __put_user(0, &frame->uc.uc_flags);
+ err |= __put_user(NULL, &frame->uc.uc_link);
+ err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
+ err |= setup_sigcontext(regs, &frame->uc.uc_mcontext);
+
+ err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
+
+ if (err)
+ return -EFAULT;
+
+ /* trampoline - the desired return ip is the retcode itself */
+ return_ip = (unsigned long)&frame->retcode;
+ /* This is:
+ l.ori r11,r0,__NR_sigreturn
+ l.sys 1
+ */
+ err |= __put_user(0xa960, (short __user *)(frame->retcode + 0));
+ err |= __put_user(__NR_rt_sigreturn, (short __user *)(frame->retcode + 2));
+ err |= __put_user(0x20000001, (unsigned long __user *)(frame->retcode + 4));
+ err |= __put_user(0x15000000, (unsigned long __user *)(frame->retcode + 8));
+
+ if (err)
+ return -EFAULT;
+
+ /* Set up registers for signal handler */
+ regs->pc = (unsigned long)ksig->ka.sa.sa_handler; /* what we enter NOW */
+ regs->gpr[9] = (unsigned long)return_ip; /* what we enter LATER */
+ regs->gpr[3] = (unsigned long)ksig->sig; /* arg 1: signo */
+ regs->gpr[4] = (unsigned long)&frame->info; /* arg 2: (siginfo_t*) */
+ regs->gpr[5] = (unsigned long)&frame->uc; /* arg 3: ucontext */
+
+ /* actually move the usp to reflect the stacked frame */
+ regs->sp = (unsigned long)frame;
+
+ return 0;
+}
+
+static inline void
+handle_signal(struct ksignal *ksig, struct pt_regs *regs)
+{
+ int ret;
+
+ ret = setup_rt_frame(ksig, sigmask_to_save(), regs);
+
+ signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
+}
+
+/*
+ * Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ *
+ * Also note that the regs structure given here as an argument, is the latest
+ * pushed pt_regs. It may or may not be the same as the first pushed registers
+ * when the initial usermode->kernelmode transition took place. Therefore
+ * we can use user_mode(regs) to see if we came directly from kernel or user
+ * mode below.
+ */
+
+static int do_signal(struct pt_regs *regs, int syscall)
+{
+ struct ksignal ksig;
+ unsigned long continue_addr = 0;
+ unsigned long restart_addr = 0;
+ unsigned long retval = 0;
+ int restart = 0;
+
+ if (syscall) {
+ continue_addr = regs->pc;
+ restart_addr = continue_addr - 4;
+ retval = regs->gpr[11];
+
+ /*
+ * Setup syscall restart here so that a debugger will
+ * see the already changed PC.
+ */
+ switch (retval) {
+ case -ERESTART_RESTARTBLOCK:
+ restart = -2;
+ fallthrough;
+ case -ERESTARTNOHAND:
+ case -ERESTARTSYS:
+ case -ERESTARTNOINTR:
+ restart++;
+ regs->gpr[11] = regs->orig_gpr11;
+ regs->pc = restart_addr;
+ break;
+ }
+ }
+
+ /*
+ * Get the signal to deliver. During the call to get_signal the
+ * debugger may change all our registers so we may need to revert
+ * the decision to restart the syscall; specifically, if the PC is
+ * changed, don't restart the syscall.
+ */
+ if (get_signal(&ksig)) {
+ if (unlikely(restart) && regs->pc == restart_addr) {
+ if (retval == -ERESTARTNOHAND ||
+ retval == -ERESTART_RESTARTBLOCK
+ || (retval == -ERESTARTSYS
+ && !(ksig.ka.sa.sa_flags & SA_RESTART))) {
+ /* No automatic restart */
+ regs->gpr[11] = -EINTR;
+ regs->pc = continue_addr;
+ }
+ }
+ handle_signal(&ksig, regs);
+ } else {
+ /* no handler */
+ restore_saved_sigmask();
+ /*
+ * Restore pt_regs PC as syscall restart will be handled by
+ * kernel without return to userspace
+ */
+ if (unlikely(restart) && regs->pc == restart_addr) {
+ regs->pc = continue_addr;
+ return restart;
+ }
+ }
+
+ return 0;
+}
+
+asmlinkage int
+do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
+{
+ do {
+ if (likely(thread_flags & _TIF_NEED_RESCHED)) {
+ schedule();
+ } else {
+ if (unlikely(!user_mode(regs)))
+ return 0;
+ local_irq_enable();
+ if (thread_flags & (_TIF_SIGPENDING|_TIF_NOTIFY_SIGNAL)) {
+ int restart = do_signal(regs, syscall);
+ if (unlikely(restart)) {
+ /*
+ * Restart without handlers.
+ * Deal with it without leaving
+ * the kernel space.
+ */
+ return restart;
+ }
+ syscall = 0;
+ } else {
+ resume_user_mode_work(regs);
+ }
+ }
+ local_irq_disable();
+ thread_flags = read_thread_flags();
+ } while (thread_flags & _TIF_WORK_MASK);
+ return 0;
+}
diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
new file mode 100644
index 0000000000..1c5a2d71d6
--- /dev/null
+++ b/arch/openrisc/kernel/smp.c
@@ -0,0 +1,332 @@
+/*
+ * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
+ *
+ * Based on arm64 and arc implementations
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/sched.h>
+#include <linux/sched/mm.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <asm/cpuinfo.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/time.h>
+
+asmlinkage __init void secondary_start_kernel(void);
+
+static void (*smp_cross_call)(const struct cpumask *, unsigned int);
+
+unsigned long secondary_release = -1;
+struct thread_info *secondary_thread_info;
+
+enum ipi_msg_type {
+ IPI_WAKEUP,
+ IPI_RESCHEDULE,
+ IPI_CALL_FUNC,
+ IPI_CALL_FUNC_SINGLE,
+};
+
+static DEFINE_SPINLOCK(boot_lock);
+
+static void boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ /*
+ * set synchronisation state between this boot processor
+ * and the secondary one
+ */
+ spin_lock(&boot_lock);
+
+ secondary_release = cpu;
+ smp_cross_call(cpumask_of(cpu), IPI_WAKEUP);
+
+ /*
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+ spin_unlock(&boot_lock);
+}
+
+void __init smp_prepare_boot_cpu(void)
+{
+}
+
+void __init smp_init_cpus(void)
+{
+ struct device_node *cpu;
+ u32 cpu_id;
+
+ for_each_of_cpu_node(cpu) {
+ cpu_id = of_get_cpu_hwid(cpu, 0);
+ if (cpu_id < NR_CPUS)
+ set_cpu_possible(cpu_id, true);
+ }
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ unsigned int cpu;
+
+ /*
+ * Initialise the present map, which describes the set of CPUs
+ * actually populated at the present time.
+ */
+ for_each_possible_cpu(cpu) {
+ if (cpu < max_cpus)
+ set_cpu_present(cpu, true);
+ }
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+}
+
+static DECLARE_COMPLETION(cpu_running);
+
+int __cpu_up(unsigned int cpu, struct task_struct *idle)
+{
+ if (smp_cross_call == NULL) {
+ pr_warn("CPU%u: failed to start, IPI controller missing",
+ cpu);
+ return -EIO;
+ }
+
+ secondary_thread_info = task_thread_info(idle);
+ current_pgd[cpu] = init_mm.pgd;
+
+ boot_secondary(cpu, idle);
+ if (!wait_for_completion_timeout(&cpu_running,
+ msecs_to_jiffies(1000))) {
+ pr_crit("CPU%u: failed to start\n", cpu);
+ return -EIO;
+ }
+ synchronise_count_master(cpu);
+
+ return 0;
+}
+
+asmlinkage __init void secondary_start_kernel(void)
+{
+ struct mm_struct *mm = &init_mm;
+ unsigned int cpu = smp_processor_id();
+ /*
+ * All kernel threads share the same mm context; grab a
+ * reference and switch to it.
+ */
+ mmgrab(mm);
+ current->active_mm = mm;
+ cpumask_set_cpu(cpu, mm_cpumask(mm));
+
+ pr_info("CPU%u: Booted secondary processor\n", cpu);
+
+ setup_cpuinfo();
+ openrisc_clockevent_init();
+
+ notify_cpu_starting(cpu);
+
+ /*
+ * OK, now it's safe to let the boot CPU continue
+ */
+ complete(&cpu_running);
+
+ synchronise_count_slave(cpu);
+ set_cpu_online(cpu, true);
+
+ local_irq_enable();
+ /*
+ * OK, it's off to the idle thread for us
+ */
+ cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
+}
+
+void handle_IPI(unsigned int ipi_msg)
+{
+ unsigned int cpu = smp_processor_id();
+
+ switch (ipi_msg) {
+ case IPI_WAKEUP:
+ break;
+
+ case IPI_RESCHEDULE:
+ scheduler_ipi();
+ break;
+
+ case IPI_CALL_FUNC:
+ generic_smp_call_function_interrupt();
+ break;
+
+ case IPI_CALL_FUNC_SINGLE:
+ generic_smp_call_function_single_interrupt();
+ break;
+
+ default:
+ WARN(1, "CPU%u: Unknown IPI message 0x%x\n", cpu, ipi_msg);
+ break;
+ }
+}
+
+void arch_smp_send_reschedule(int cpu)
+{
+ smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
+}
+
+static void stop_this_cpu(void *dummy)
+{
+ /* Remove this CPU */
+ set_cpu_online(smp_processor_id(), false);
+
+ local_irq_disable();
+ /* CPU Doze */
+ if (mfspr(SPR_UPR) & SPR_UPR_PMP)
+ mtspr(SPR_PMR, mfspr(SPR_PMR) | SPR_PMR_DME);
+ /* If that didn't work, infinite loop */
+ while (1)
+ ;
+}
+
+void smp_send_stop(void)
+{
+ smp_call_function(stop_this_cpu, NULL, 0);
+}
+
+void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
+{
+ smp_cross_call = fn;
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_CALL_FUNC);
+}
+
+/* TLB flush operations - Performed on each CPU*/
+static inline void ipi_flush_tlb_all(void *ignored)
+{
+ local_flush_tlb_all();
+}
+
+static inline void ipi_flush_tlb_mm(void *info)
+{
+ struct mm_struct *mm = (struct mm_struct *)info;
+
+ local_flush_tlb_mm(mm);
+}
+
+static void smp_flush_tlb_mm(struct cpumask *cmask, struct mm_struct *mm)
+{
+ unsigned int cpuid;
+
+ if (cpumask_empty(cmask))
+ return;
+
+ cpuid = get_cpu();
+
+ if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
+ /* local cpu is the only cpu present in cpumask */
+ local_flush_tlb_mm(mm);
+ } else {
+ on_each_cpu_mask(cmask, ipi_flush_tlb_mm, mm, 1);
+ }
+ put_cpu();
+}
+
+struct flush_tlb_data {
+ unsigned long addr1;
+ unsigned long addr2;
+};
+
+static inline void ipi_flush_tlb_page(void *info)
+{
+ struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
+
+ local_flush_tlb_page(NULL, fd->addr1);
+}
+
+static inline void ipi_flush_tlb_range(void *info)
+{
+ struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
+
+ local_flush_tlb_range(NULL, fd->addr1, fd->addr2);
+}
+
+static void smp_flush_tlb_range(const struct cpumask *cmask, unsigned long start,
+ unsigned long end)
+{
+ unsigned int cpuid;
+
+ if (cpumask_empty(cmask))
+ return;
+
+ cpuid = get_cpu();
+
+ if (cpumask_any_but(cmask, cpuid) >= nr_cpu_ids) {
+ /* local cpu is the only cpu present in cpumask */
+ if ((end - start) <= PAGE_SIZE)
+ local_flush_tlb_page(NULL, start);
+ else
+ local_flush_tlb_range(NULL, start, end);
+ } else {
+ struct flush_tlb_data fd;
+
+ fd.addr1 = start;
+ fd.addr2 = end;
+
+ if ((end - start) <= PAGE_SIZE)
+ on_each_cpu_mask(cmask, ipi_flush_tlb_page, &fd, 1);
+ else
+ on_each_cpu_mask(cmask, ipi_flush_tlb_range, &fd, 1);
+ }
+ put_cpu();
+}
+
+void flush_tlb_all(void)
+{
+ on_each_cpu(ipi_flush_tlb_all, NULL, 1);
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+ smp_flush_tlb_mm(mm_cpumask(mm), mm);
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
+{
+ smp_flush_tlb_range(mm_cpumask(vma->vm_mm), uaddr, uaddr + PAGE_SIZE);
+}
+
+void flush_tlb_range(struct vm_area_struct *vma,
+ unsigned long start, unsigned long end)
+{
+ const struct cpumask *cmask = vma ? mm_cpumask(vma->vm_mm)
+ : cpu_online_mask;
+ smp_flush_tlb_range(cmask, start, end);
+}
+
+/* Instruction cache invalidate - performed on each cpu */
+static void ipi_icache_page_inv(void *arg)
+{
+ struct page *page = arg;
+
+ local_icache_page_inv(page);
+}
+
+void smp_icache_page_inv(struct page *page)
+{
+ on_each_cpu(ipi_icache_page_inv, page, 1);
+}
+EXPORT_SYMBOL(smp_icache_page_inv);
diff --git a/arch/openrisc/kernel/stacktrace.c b/arch/openrisc/kernel/stacktrace.c
new file mode 100644
index 0000000000..54d38809e2
--- /dev/null
+++ b/arch/openrisc/kernel/stacktrace.c
@@ -0,0 +1,100 @@
+/*
+ * Stack trace utility for OpenRISC
+ *
+ * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ *
+ * Losely based on work from sh and powerpc.
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/stacktrace.h>
+
+#include <asm/processor.h>
+#include <asm/unwinder.h>
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ */
+static void
+save_stack_address(void *data, unsigned long addr, int reliable)
+{
+ struct stack_trace *trace = data;
+
+ if (!reliable)
+ return;
+
+ if (trace->skip > 0) {
+ trace->skip--;
+ return;
+ }
+
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = addr;
+}
+
+void save_stack_trace(struct stack_trace *trace)
+{
+ unwind_stack(trace, (unsigned long *) &trace, save_stack_address);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace);
+
+static void
+save_stack_address_nosched(void *data, unsigned long addr, int reliable)
+{
+ struct stack_trace *trace = (struct stack_trace *)data;
+
+ if (!reliable)
+ return;
+
+ if (in_sched_functions(addr))
+ return;
+
+ if (trace->skip > 0) {
+ trace->skip--;
+ return;
+ }
+
+ if (trace->nr_entries < trace->max_entries)
+ trace->entries[trace->nr_entries++] = addr;
+}
+
+void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
+{
+ unsigned long *sp = NULL;
+
+ if (!try_get_task_stack(tsk))
+ return;
+
+ if (tsk == current)
+ sp = (unsigned long *) &sp;
+ else {
+ unsigned long ksp;
+
+ /* Locate stack from kernel context */
+ ksp = task_thread_info(tsk)->ksp;
+ ksp += STACK_FRAME_OVERHEAD; /* redzone */
+ ksp += sizeof(struct pt_regs);
+
+ sp = (unsigned long *) ksp;
+ }
+
+ unwind_stack(trace, sp, save_stack_address_nosched);
+
+ put_task_stack(tsk);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
+
+void
+save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
+{
+ unwind_stack(trace, (unsigned long *) regs->sp,
+ save_stack_address_nosched);
+}
+EXPORT_SYMBOL_GPL(save_stack_trace_regs);
diff --git a/arch/openrisc/kernel/sync-timer.c b/arch/openrisc/kernel/sync-timer.c
new file mode 100644
index 0000000000..ed8d835cac
--- /dev/null
+++ b/arch/openrisc/kernel/sync-timer.c
@@ -0,0 +1,120 @@
+/*
+ * OR1K timer synchronisation
+ *
+ * Based on work from MIPS implementation.
+ *
+ * All CPUs will have their count registers synchronised to the CPU0 next time
+ * value. This can cause a small timewarp for CPU0. All other CPU's should
+ * not have done anything significant (but they may have had interrupts
+ * enabled briefly - prom_smp_finish() should not be responsible for enabling
+ * interrupts...)
+ */
+
+#include <linux/kernel.h>
+#include <linux/irqflags.h>
+#include <linux/cpumask.h>
+
+#include <asm/time.h>
+#include <asm/timex.h>
+#include <linux/atomic.h>
+#include <asm/barrier.h>
+
+#include <asm/spr.h>
+
+static unsigned int initcount;
+static atomic_t count_count_start = ATOMIC_INIT(0);
+static atomic_t count_count_stop = ATOMIC_INIT(0);
+
+#define COUNTON 100
+#define NR_LOOPS 3
+
+void synchronise_count_master(int cpu)
+{
+ int i;
+ unsigned long flags;
+
+ pr_info("Synchronize counters for CPU %u: ", cpu);
+
+ local_irq_save(flags);
+
+ /*
+ * We loop a few times to get a primed instruction cache,
+ * then the last pass is more or less synchronised and
+ * the master and slaves each set their cycle counters to a known
+ * value all at once. This reduces the chance of having random offsets
+ * between the processors, and guarantees that the maximum
+ * delay between the cycle counters is never bigger than
+ * the latency of information-passing (cachelines) between
+ * two CPUs.
+ */
+
+ for (i = 0; i < NR_LOOPS; i++) {
+ /* slaves loop on '!= 2' */
+ while (atomic_read(&count_count_start) != 1)
+ mb();
+ atomic_set(&count_count_stop, 0);
+ smp_wmb();
+
+ /* Let the slave writes its count register */
+ atomic_inc(&count_count_start);
+
+ /* Count will be initialised to current timer */
+ if (i == 1)
+ initcount = get_cycles();
+
+ /*
+ * Everyone initialises count in the last loop:
+ */
+ if (i == NR_LOOPS-1)
+ openrisc_timer_set(initcount);
+
+ /*
+ * Wait for slave to leave the synchronization point:
+ */
+ while (atomic_read(&count_count_stop) != 1)
+ mb();
+ atomic_set(&count_count_start, 0);
+ smp_wmb();
+ atomic_inc(&count_count_stop);
+ }
+ /* Arrange for an interrupt in a short while */
+ openrisc_timer_set_next(COUNTON);
+
+ local_irq_restore(flags);
+
+ /*
+ * i386 code reported the skew here, but the
+ * count registers were almost certainly out of sync
+ * so no point in alarming people
+ */
+ pr_cont("done.\n");
+}
+
+void synchronise_count_slave(int cpu)
+{
+ int i;
+
+ /*
+ * Not every cpu is online at the time this gets called,
+ * so we first wait for the master to say everyone is ready
+ */
+
+ for (i = 0; i < NR_LOOPS; i++) {
+ atomic_inc(&count_count_start);
+ while (atomic_read(&count_count_start) != 2)
+ mb();
+
+ /*
+ * Everyone initialises count in the last loop:
+ */
+ if (i == NR_LOOPS-1)
+ openrisc_timer_set(initcount);
+
+ atomic_inc(&count_count_stop);
+ while (atomic_read(&count_count_stop) != 2)
+ mb();
+ }
+ /* Arrange for an interrupt in a short while */
+ openrisc_timer_set_next(COUNTON);
+}
+#undef NR_LOOPS
diff --git a/arch/openrisc/kernel/sys_call_table.c b/arch/openrisc/kernel/sys_call_table.c
new file mode 100644
index 0000000000..3d18008310
--- /dev/null
+++ b/arch/openrisc/kernel/sys_call_table.c
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC sys_call_table.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/syscalls.h>
+#include <linux/signal.h>
+#include <linux/unistd.h>
+
+#include <asm/syscalls.h>
+
+#undef __SYSCALL
+#define __SYSCALL(nr, call) [nr] = (call),
+
+void *sys_call_table[__NR_syscalls] = {
+#include <asm/unistd.h>
+};
diff --git a/arch/openrisc/kernel/time.c b/arch/openrisc/kernel/time.c
new file mode 100644
index 0000000000..764c7bfb5d
--- /dev/null
+++ b/arch/openrisc/kernel/time.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC time.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ */
+
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/interrupt.h>
+#include <linux/ftrace.h>
+
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of_clk.h>
+
+#include <asm/cpuinfo.h>
+#include <asm/time.h>
+
+irqreturn_t __irq_entry timer_interrupt(struct pt_regs *regs);
+
+/* Test the timer ticks to count, used in sync routine */
+inline void openrisc_timer_set(unsigned long count)
+{
+ mtspr(SPR_TTCR, count);
+}
+
+/* Set the timer to trigger in delta cycles */
+inline void openrisc_timer_set_next(unsigned long delta)
+{
+ u32 c;
+
+ /* Read 32-bit counter value, add delta, mask off the low 28 bits.
+ * We're guaranteed delta won't be bigger than 28 bits because the
+ * generic timekeeping code ensures that for us.
+ */
+ c = mfspr(SPR_TTCR);
+ c += delta;
+ c &= SPR_TTMR_TP;
+
+ /* Set counter and enable interrupt.
+ * Keep timer in continuous mode always.
+ */
+ mtspr(SPR_TTMR, SPR_TTMR_CR | SPR_TTMR_IE | c);
+}
+
+static int openrisc_timer_set_next_event(unsigned long delta,
+ struct clock_event_device *dev)
+{
+ openrisc_timer_set_next(delta);
+ return 0;
+}
+
+/* This is the clock event device based on the OR1K tick timer.
+ * As the timer is being used as a continuous clock-source (required for HR
+ * timers) we cannot enable the PERIODIC feature. The tick timer can run using
+ * one-shot events, so no problem.
+ */
+static DEFINE_PER_CPU(struct clock_event_device, clockevent_openrisc_timer);
+
+void openrisc_clockevent_init(void)
+{
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *evt =
+ &per_cpu(clockevent_openrisc_timer, cpu);
+ struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[cpu];
+
+ mtspr(SPR_TTMR, SPR_TTMR_CR);
+
+#ifdef CONFIG_SMP
+ evt->broadcast = tick_broadcast;
+#endif
+ evt->name = "openrisc_timer_clockevent",
+ evt->features = CLOCK_EVT_FEAT_ONESHOT,
+ evt->rating = 300,
+ evt->set_next_event = openrisc_timer_set_next_event,
+
+ evt->cpumask = cpumask_of(cpu);
+
+ /* We only have 28 bits */
+ clockevents_config_and_register(evt, cpuinfo->clock_frequency,
+ 100, 0x0fffffff);
+
+}
+
+static inline void timer_ack(void)
+{
+ /* Clear the IP bit and disable further interrupts */
+ /* This can be done very simply... we just need to keep the timer
+ running, so just maintain the CR bits while clearing the rest
+ of the register
+ */
+ mtspr(SPR_TTMR, SPR_TTMR_CR);
+}
+
+/*
+ * The timer interrupt is mostly handled in generic code nowadays... this
+ * function just acknowledges the interrupt and fires the event handler that
+ * has been set on the clockevent device by the generic time management code.
+ *
+ * This function needs to be called by the timer exception handler and that's
+ * all the exception handler needs to do.
+ */
+
+irqreturn_t __irq_entry timer_interrupt(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ unsigned int cpu = smp_processor_id();
+ struct clock_event_device *evt =
+ &per_cpu(clockevent_openrisc_timer, cpu);
+
+ timer_ack();
+
+ /*
+ * update_process_times() expects us to have called irq_enter().
+ */
+ irq_enter();
+ evt->event_handler(evt);
+ irq_exit();
+
+ set_irq_regs(old_regs);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Clocksource: Based on OpenRISC timer/counter
+ *
+ * This sets up the OpenRISC Tick Timer as a clock source. The tick timer
+ * is 32 bits wide and runs at the CPU clock frequency.
+ */
+static u64 openrisc_timer_read(struct clocksource *cs)
+{
+ return (u64) mfspr(SPR_TTCR);
+}
+
+static struct clocksource openrisc_timer = {
+ .name = "openrisc_timer",
+ .rating = 200,
+ .read = openrisc_timer_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init openrisc_timer_init(void)
+{
+ struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
+
+ if (clocksource_register_hz(&openrisc_timer, cpuinfo->clock_frequency))
+ panic("failed to register clocksource");
+
+ /* Enable the incrementer: 'continuous' mode with interrupt disabled */
+ mtspr(SPR_TTMR, SPR_TTMR_CR);
+
+ return 0;
+}
+
+void __init time_init(void)
+{
+ u32 upr;
+
+ upr = mfspr(SPR_UPR);
+ if (!(upr & SPR_UPR_TTP))
+ panic("Linux not supported on devices without tick timer");
+
+ openrisc_timer_init();
+ openrisc_clockevent_init();
+
+ of_clk_init(NULL);
+ timer_probe();
+}
diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c
new file mode 100644
index 0000000000..9370888c9a
--- /dev/null
+++ b/arch/openrisc/kernel/traps.c
@@ -0,0 +1,427 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * OpenRISC traps.c
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * Here we handle the break vectors not used by the system call
+ * mechanism, as well as some general stack/register dumping
+ * things.
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/sched/debug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/kernel.h>
+#include <linux/extable.h>
+#include <linux/kmod.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+
+#include <asm/bug.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/unwinder.h>
+#include <asm/sections.h>
+
+int lwa_flag;
+static unsigned long __user *lwa_addr;
+
+asmlinkage void unhandled_exception(struct pt_regs *regs, int ea, int vector);
+asmlinkage void do_trap(struct pt_regs *regs, unsigned long address);
+asmlinkage void do_fpe_trap(struct pt_regs *regs, unsigned long address);
+asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address);
+asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address);
+asmlinkage void do_illegal_instruction(struct pt_regs *regs,
+ unsigned long address);
+
+static void print_trace(void *data, unsigned long addr, int reliable)
+{
+ const char *loglvl = data;
+
+ printk("%s[<%p>] %s%pS\n", loglvl, (void *) addr, reliable ? "" : "? ",
+ (void *) addr);
+}
+
+static void print_data(unsigned long base_addr, unsigned long word, int i)
+{
+ if (i == 0)
+ printk("(%08lx:)\t%08lx", base_addr + (i * 4), word);
+ else
+ printk(" %08lx:\t%08lx", base_addr + (i * 4), word);
+}
+
+/* displays a short stack trace */
+void show_stack(struct task_struct *task, unsigned long *esp, const char *loglvl)
+{
+ if (esp == NULL)
+ esp = (unsigned long *)&esp;
+
+ printk("%sCall trace:\n", loglvl);
+ unwind_stack((void *)loglvl, esp, print_trace);
+}
+
+void show_registers(struct pt_regs *regs)
+{
+ int i;
+ int in_kernel = 1;
+ unsigned long esp;
+
+ esp = (unsigned long)(regs->sp);
+ if (user_mode(regs))
+ in_kernel = 0;
+
+ printk("CPU #: %d\n"
+ " PC: %08lx SR: %08lx SP: %08lx FPCSR: %08lx\n",
+ smp_processor_id(), regs->pc, regs->sr, regs->sp,
+ regs->fpcsr);
+ printk("GPR00: %08lx GPR01: %08lx GPR02: %08lx GPR03: %08lx\n",
+ 0L, regs->gpr[1], regs->gpr[2], regs->gpr[3]);
+ printk("GPR04: %08lx GPR05: %08lx GPR06: %08lx GPR07: %08lx\n",
+ regs->gpr[4], regs->gpr[5], regs->gpr[6], regs->gpr[7]);
+ printk("GPR08: %08lx GPR09: %08lx GPR10: %08lx GPR11: %08lx\n",
+ regs->gpr[8], regs->gpr[9], regs->gpr[10], regs->gpr[11]);
+ printk("GPR12: %08lx GPR13: %08lx GPR14: %08lx GPR15: %08lx\n",
+ regs->gpr[12], regs->gpr[13], regs->gpr[14], regs->gpr[15]);
+ printk("GPR16: %08lx GPR17: %08lx GPR18: %08lx GPR19: %08lx\n",
+ regs->gpr[16], regs->gpr[17], regs->gpr[18], regs->gpr[19]);
+ printk("GPR20: %08lx GPR21: %08lx GPR22: %08lx GPR23: %08lx\n",
+ regs->gpr[20], regs->gpr[21], regs->gpr[22], regs->gpr[23]);
+ printk("GPR24: %08lx GPR25: %08lx GPR26: %08lx GPR27: %08lx\n",
+ regs->gpr[24], regs->gpr[25], regs->gpr[26], regs->gpr[27]);
+ printk("GPR28: %08lx GPR29: %08lx GPR30: %08lx GPR31: %08lx\n",
+ regs->gpr[28], regs->gpr[29], regs->gpr[30], regs->gpr[31]);
+ printk(" RES: %08lx oGPR11: %08lx\n",
+ regs->gpr[11], regs->orig_gpr11);
+
+ printk("Process %s (pid: %d, stackpage=%08lx)\n",
+ current->comm, current->pid, (unsigned long)current);
+ /*
+ * When in-kernel, we also print out the stack and code at the
+ * time of the fault..
+ */
+ if (in_kernel) {
+
+ printk("\nStack: ");
+ show_stack(NULL, (unsigned long *)esp, KERN_EMERG);
+
+ if (esp < PAGE_OFFSET)
+ goto bad_stack;
+
+ printk("\n");
+ for (i = -8; i < 24; i += 1) {
+ unsigned long word;
+
+ if (__get_user(word, &((unsigned long *)esp)[i])) {
+bad_stack:
+ printk(" Bad Stack value.");
+ break;
+ }
+
+ print_data(esp, word, i);
+ }
+
+ printk("\nCode: ");
+ if (regs->pc < PAGE_OFFSET)
+ goto bad;
+
+ for (i = -6; i < 6; i += 1) {
+ unsigned long word;
+
+ if (__get_user(word, &((unsigned long *)regs->pc)[i])) {
+bad:
+ printk(" Bad PC value.");
+ break;
+ }
+
+ print_data(regs->pc, word, i);
+ }
+ }
+ printk("\n");
+}
+
+/* This is normally the 'Oops' routine */
+void __noreturn die(const char *str, struct pt_regs *regs, long err)
+{
+
+ console_verbose();
+ printk("\n%s#: %04lx\n", str, err & 0xffff);
+ show_registers(regs);
+#ifdef CONFIG_JUMP_UPON_UNHANDLED_EXCEPTION
+ printk("\n\nUNHANDLED_EXCEPTION: entering infinite loop\n");
+
+ /* shut down interrupts */
+ local_irq_disable();
+
+ __asm__ __volatile__("l.nop 1");
+ do {} while (1);
+#endif
+ make_task_dead(SIGSEGV);
+}
+
+asmlinkage void unhandled_exception(struct pt_regs *regs, int ea, int vector)
+{
+ printk("Unable to handle exception at EA =0x%x, vector 0x%x",
+ ea, vector);
+ die("Oops", regs, 9);
+}
+
+asmlinkage void do_fpe_trap(struct pt_regs *regs, unsigned long address)
+{
+ int code = FPE_FLTUNK;
+ unsigned long fpcsr = regs->fpcsr;
+
+ if (fpcsr & SPR_FPCSR_IVF)
+ code = FPE_FLTINV;
+ else if (fpcsr & SPR_FPCSR_OVF)
+ code = FPE_FLTOVF;
+ else if (fpcsr & SPR_FPCSR_UNF)
+ code = FPE_FLTUND;
+ else if (fpcsr & SPR_FPCSR_DZF)
+ code = FPE_FLTDIV;
+ else if (fpcsr & SPR_FPCSR_IXF)
+ code = FPE_FLTRES;
+
+ /* Clear all flags */
+ regs->fpcsr &= ~SPR_FPCSR_ALLF;
+
+ force_sig_fault(SIGFPE, code, (void __user *)regs->pc);
+}
+
+asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
+{
+ force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc);
+}
+
+asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
+{
+ if (user_mode(regs)) {
+ /* Send a SIGBUS */
+ force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)address);
+ } else {
+ printk("KERNEL: Unaligned Access 0x%.8lx\n", address);
+ show_registers(regs);
+ die("Die:", regs, address);
+ }
+
+}
+
+asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
+{
+ if (user_mode(regs)) {
+ /* Send a SIGBUS */
+ force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address);
+ } else { /* Kernel mode */
+ printk("KERNEL: Bus error (SIGBUS) 0x%.8lx\n", address);
+ show_registers(regs);
+ die("Die:", regs, address);
+ }
+}
+
+static inline int in_delay_slot(struct pt_regs *regs)
+{
+#ifdef CONFIG_OPENRISC_NO_SPR_SR_DSX
+ /* No delay slot flag, do the old way */
+ unsigned int op, insn;
+
+ insn = *((unsigned int *)regs->pc);
+ op = insn >> 26;
+ switch (op) {
+ case 0x00: /* l.j */
+ case 0x01: /* l.jal */
+ case 0x03: /* l.bnf */
+ case 0x04: /* l.bf */
+ case 0x11: /* l.jr */
+ case 0x12: /* l.jalr */
+ return 1;
+ default:
+ return 0;
+ }
+#else
+ return mfspr(SPR_SR) & SPR_SR_DSX;
+#endif
+}
+
+static inline void adjust_pc(struct pt_regs *regs, unsigned long address)
+{
+ int displacement;
+ unsigned int rb, op, jmp;
+
+ if (unlikely(in_delay_slot(regs))) {
+ /* In delay slot, instruction at pc is a branch, simulate it */
+ jmp = *((unsigned int *)regs->pc);
+
+ displacement = sign_extend32(((jmp) & 0x3ffffff) << 2, 27);
+ rb = (jmp & 0x0000ffff) >> 11;
+ op = jmp >> 26;
+
+ switch (op) {
+ case 0x00: /* l.j */
+ regs->pc += displacement;
+ return;
+ case 0x01: /* l.jal */
+ regs->pc += displacement;
+ regs->gpr[9] = regs->pc + 8;
+ return;
+ case 0x03: /* l.bnf */
+ if (regs->sr & SPR_SR_F)
+ regs->pc += 8;
+ else
+ regs->pc += displacement;
+ return;
+ case 0x04: /* l.bf */
+ if (regs->sr & SPR_SR_F)
+ regs->pc += displacement;
+ else
+ regs->pc += 8;
+ return;
+ case 0x11: /* l.jr */
+ regs->pc = regs->gpr[rb];
+ return;
+ case 0x12: /* l.jalr */
+ regs->pc = regs->gpr[rb];
+ regs->gpr[9] = regs->pc + 8;
+ return;
+ default:
+ break;
+ }
+ } else {
+ regs->pc += 4;
+ }
+}
+
+static inline void simulate_lwa(struct pt_regs *regs, unsigned long address,
+ unsigned int insn)
+{
+ unsigned int ra, rd;
+ unsigned long value;
+ unsigned long orig_pc;
+ long imm;
+
+ const struct exception_table_entry *entry;
+
+ orig_pc = regs->pc;
+ adjust_pc(regs, address);
+
+ ra = (insn >> 16) & 0x1f;
+ rd = (insn >> 21) & 0x1f;
+ imm = (short)insn;
+ lwa_addr = (unsigned long __user *)(regs->gpr[ra] + imm);
+
+ if ((unsigned long)lwa_addr & 0x3) {
+ do_unaligned_access(regs, address);
+ return;
+ }
+
+ if (get_user(value, lwa_addr)) {
+ if (user_mode(regs)) {
+ force_sig(SIGSEGV);
+ return;
+ }
+
+ if ((entry = search_exception_tables(orig_pc))) {
+ regs->pc = entry->fixup;
+ return;
+ }
+
+ /* kernel access in kernel space, load it directly */
+ value = *((unsigned long *)lwa_addr);
+ }
+
+ lwa_flag = 1;
+ regs->gpr[rd] = value;
+}
+
+static inline void simulate_swa(struct pt_regs *regs, unsigned long address,
+ unsigned int insn)
+{
+ unsigned long __user *vaddr;
+ unsigned long orig_pc;
+ unsigned int ra, rb;
+ long imm;
+
+ const struct exception_table_entry *entry;
+
+ orig_pc = regs->pc;
+ adjust_pc(regs, address);
+
+ ra = (insn >> 16) & 0x1f;
+ rb = (insn >> 11) & 0x1f;
+ imm = (short)(((insn & 0x2200000) >> 10) | (insn & 0x7ff));
+ vaddr = (unsigned long __user *)(regs->gpr[ra] + imm);
+
+ if (!lwa_flag || vaddr != lwa_addr) {
+ regs->sr &= ~SPR_SR_F;
+ return;
+ }
+
+ if ((unsigned long)vaddr & 0x3) {
+ do_unaligned_access(regs, address);
+ return;
+ }
+
+ if (put_user(regs->gpr[rb], vaddr)) {
+ if (user_mode(regs)) {
+ force_sig(SIGSEGV);
+ return;
+ }
+
+ if ((entry = search_exception_tables(orig_pc))) {
+ regs->pc = entry->fixup;
+ return;
+ }
+
+ /* kernel access in kernel space, store it directly */
+ *((unsigned long *)vaddr) = regs->gpr[rb];
+ }
+
+ lwa_flag = 0;
+ regs->sr |= SPR_SR_F;
+}
+
+#define INSN_LWA 0x1b
+#define INSN_SWA 0x33
+
+asmlinkage void do_illegal_instruction(struct pt_regs *regs,
+ unsigned long address)
+{
+ unsigned int op;
+ unsigned int insn = *((unsigned int *)address);
+
+ op = insn >> 26;
+
+ switch (op) {
+ case INSN_LWA:
+ simulate_lwa(regs, address, insn);
+ return;
+
+ case INSN_SWA:
+ simulate_swa(regs, address, insn);
+ return;
+
+ default:
+ break;
+ }
+
+ if (user_mode(regs)) {
+ /* Send a SIGILL */
+ force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)address);
+ } else { /* Kernel mode */
+ printk("KERNEL: Illegal instruction (SIGILL) 0x%.8lx\n",
+ address);
+ show_registers(regs);
+ die("Die:", regs, address);
+ }
+}
diff --git a/arch/openrisc/kernel/unwinder.c b/arch/openrisc/kernel/unwinder.c
new file mode 100644
index 0000000000..c6ad6f867a
--- /dev/null
+++ b/arch/openrisc/kernel/unwinder.c
@@ -0,0 +1,105 @@
+/*
+ * OpenRISC unwinder.c
+ *
+ * Reusable arch specific api for unwinding stacks.
+ *
+ * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/sched/task_stack.h>
+#include <linux/kernel.h>
+
+#include <asm/unwinder.h>
+
+#ifdef CONFIG_FRAME_POINTER
+struct or1k_frameinfo {
+ unsigned long *fp;
+ unsigned long ra;
+ unsigned long top;
+};
+
+/*
+ * Verify a frameinfo structure. The return address should be a valid text
+ * address. The frame pointer may be null if its the last frame, otherwise
+ * the frame pointer should point to a location in the stack after the
+ * top of the next frame up.
+ */
+static inline int or1k_frameinfo_valid(struct or1k_frameinfo *frameinfo)
+{
+ return (frameinfo->fp == NULL ||
+ (!kstack_end(frameinfo->fp) &&
+ frameinfo->fp > &frameinfo->top)) &&
+ __kernel_text_address(frameinfo->ra);
+}
+
+/*
+ * Create a stack trace doing scanning which is frame pointer aware. We can
+ * get reliable stack traces by matching the previously found frame
+ * pointer with the top of the stack address every time we find a valid
+ * or1k_frameinfo.
+ *
+ * Ideally the stack parameter will be passed as FP, but it can not be
+ * guaranteed. Therefore we scan each address looking for the first sign
+ * of a return address.
+ *
+ * The OpenRISC stack frame looks something like the following. The
+ * location SP is held in r1 and location FP is held in r2 when frame pointers
+ * enabled.
+ *
+ * SP -> (top of stack)
+ * - (callee saved registers)
+ * - (local variables)
+ * FP-8 -> previous FP \
+ * FP-4 -> return address |- or1k_frameinfo
+ * FP -> (previous top of stack) /
+ */
+void unwind_stack(void *data, unsigned long *stack,
+ void (*trace)(void *data, unsigned long addr, int reliable))
+{
+ unsigned long *next_fp = NULL;
+ struct or1k_frameinfo *frameinfo = NULL;
+ int reliable = 0;
+
+ while (!kstack_end(stack)) {
+ frameinfo = container_of(stack,
+ struct or1k_frameinfo,
+ top);
+
+ if (__kernel_text_address(frameinfo->ra)) {
+ if (or1k_frameinfo_valid(frameinfo) &&
+ (next_fp == NULL ||
+ next_fp == &frameinfo->top)) {
+ reliable = 1;
+ next_fp = frameinfo->fp;
+ } else
+ reliable = 0;
+
+ trace(data, frameinfo->ra, reliable);
+ }
+ stack++;
+ }
+}
+
+#else /* CONFIG_FRAME_POINTER */
+
+/*
+ * Create a stack trace by doing a simple scan treating all text addresses
+ * as return addresses.
+ */
+void unwind_stack(void *data, unsigned long *stack,
+ void (*trace)(void *data, unsigned long addr, int reliable))
+{
+ unsigned long addr;
+
+ while (!kstack_end(stack)) {
+ addr = *stack++;
+ if (__kernel_text_address(addr))
+ trace(data, addr, 0);
+ }
+}
+#endif /* CONFIG_FRAME_POINTER */
+
diff --git a/arch/openrisc/kernel/vmlinux.h b/arch/openrisc/kernel/vmlinux.h
new file mode 100644
index 0000000000..bdea46c617
--- /dev/null
+++ b/arch/openrisc/kernel/vmlinux.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __OPENRISC_VMLINUX_H_
+#define __OPENRISC_VMLINUX_H_
+
+#ifdef CONFIG_BLK_DEV_INITRD
+extern char __initrd_start, __initrd_end;
+#endif
+
+#endif
diff --git a/arch/openrisc/kernel/vmlinux.lds.S b/arch/openrisc/kernel/vmlinux.lds.S
new file mode 100644
index 0000000000..bc13060478
--- /dev/null
+++ b/arch/openrisc/kernel/vmlinux.lds.S
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * OpenRISC vmlinux.lds.S
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * Modifications for the OpenRISC architecture:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ *
+ * ld script for OpenRISC architecture
+ */
+
+/* TODO
+ * - clean up __offset & stuff
+ * - change all 8192 alignment to PAGE !!!
+ * - recheck if all alignments are really needed
+ */
+
+# define LOAD_OFFSET PAGE_OFFSET
+# define LOAD_BASE PAGE_OFFSET
+
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/thread_info.h>
+#include <asm-generic/vmlinux.lds.h>
+
+#ifdef __OR1K__
+#define __OUTPUT_FORMAT "elf32-or1k"
+#else
+#define __OUTPUT_FORMAT "elf32-or32"
+#endif
+
+OUTPUT_FORMAT(__OUTPUT_FORMAT, __OUTPUT_FORMAT, __OUTPUT_FORMAT)
+jiffies = jiffies_64 + 4;
+
+SECTIONS
+{
+ /* Read-only sections, merged into text segment: */
+ . = LOAD_BASE ;
+
+ _text = .;
+
+ /* _s_kernel_ro must be page aligned */
+ . = ALIGN(PAGE_SIZE);
+ _s_kernel_ro = .;
+
+ .text : AT(ADDR(.text) - LOAD_OFFSET)
+ {
+ _stext = .;
+ TEXT_TEXT
+ SCHED_TEXT
+ LOCK_TEXT
+ KPROBES_TEXT
+ IRQENTRY_TEXT
+ SOFTIRQENTRY_TEXT
+ *(.fixup)
+ *(.text.__*)
+ _etext = .;
+ }
+ /* TODO: Check if fixup and text.__* are really necessary
+ * fixup is definitely necessary
+ */
+
+ _sdata = .;
+
+ /* Page alignment required for RO_DATA */
+ RO_DATA(PAGE_SIZE)
+ _e_kernel_ro = .;
+
+ /* Whatever comes after _e_kernel_ro had better be page-aligend, too */
+
+ /* 32 here is cacheline size... recheck this */
+ RW_DATA(32, PAGE_SIZE, PAGE_SIZE)
+
+ _edata = .;
+
+ EXCEPTION_TABLE(4)
+
+ /* Init code and data */
+ . = ALIGN(PAGE_SIZE);
+ __init_begin = .;
+
+ HEAD_TEXT_SECTION
+
+ /* Page aligned */
+ INIT_TEXT_SECTION(PAGE_SIZE)
+
+ /* Align __setup_start on 16 byte boundary */
+ INIT_DATA_SECTION(16)
+
+ PERCPU_SECTION(L1_CACHE_BYTES)
+
+ __init_end = .;
+
+ BSS_SECTION(0, 0, 0x20)
+
+ _end = .;
+
+ /* Throw in the debugging sections */
+ STABS_DEBUG
+ DWARF_DEBUG
+ ELF_DETAILS
+
+ /* Sections to be discarded -- must be last */
+ DISCARDS
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 06:41:29 +0000