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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
| commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
| tree | a94efe259b9009378be6d90eb30d2b019d95c194 /arch/arc/kernel | |
| parent | Initial commit. (diff) | |
| download | linux-upstream/5.10.209.tar.xz linux-upstream/5.10.209.zip | |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arc/kernel')
36 files changed, 9356 insertions, 0 deletions
diff --git a/arch/arc/kernel/.gitignore b/arch/arc/kernel/.gitignore new file mode 100644 index 000000000..bbb90f92d --- /dev/null +++ b/arch/arc/kernel/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +vmlinux.lds diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile new file mode 100644 index 000000000..8c4fc4b54 --- /dev/null +++ b/arch/arc/kernel/Makefile @@ -0,0 +1,34 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) +# + +obj-y := arcksyms.o setup.o irq.o reset.o ptrace.o process.o devtree.o +obj-y += signal.o traps.o sys.o troubleshoot.o stacktrace.o disasm.o +obj-$(CONFIG_ISA_ARCOMPACT) += entry-compact.o intc-compact.o +obj-$(CONFIG_ISA_ARCV2) += entry-arcv2.o intc-arcv2.o + +obj-$(CONFIG_MODULES) += arcksyms.o module.o +obj-$(CONFIG_SMP) += smp.o +obj-$(CONFIG_ARC_MCIP) += mcip.o +obj-$(CONFIG_ARC_DW2_UNWIND) += unwind.o +obj-$(CONFIG_KPROBES) += kprobes.o +obj-$(CONFIG_ARC_EMUL_UNALIGNED) += unaligned.o +obj-$(CONFIG_KGDB) += kgdb.o +obj-$(CONFIG_ARC_METAWARE_HLINK) += arc_hostlink.o +obj-$(CONFIG_PERF_EVENTS) += perf_event.o +obj-$(CONFIG_JUMP_LABEL) += jump_label.o + +obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o +ifdef CONFIG_ISA_ARCOMPACT +CFLAGS_fpu.o += -mdpfp +endif + +ifdef CONFIG_ARC_DW2_UNWIND +CFLAGS_ctx_sw.o += -fno-omit-frame-pointer +obj-y += ctx_sw.o +else +obj-y += ctx_sw_asm.o +endif + +extra-y := vmlinux.lds head.o diff --git a/arch/arc/kernel/arc_hostlink.c b/arch/arc/kernel/arc_hostlink.c new file mode 100644 index 000000000..08c5196ef --- /dev/null +++ b/arch/arc/kernel/arc_hostlink.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * arc_hostlink.c: Pseudo-driver for Metaware provided "hostlink" facility + * + * Allows Linux userland access to host in absence of any peripherals. + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/fs.h> /* file_operations */ +#include <linux/miscdevice.h> +#include <linux/mm.h> /* VM_IO */ +#include <linux/module.h> +#include <linux/uaccess.h> + +static unsigned char __HOSTLINK__[4 * PAGE_SIZE] __aligned(PAGE_SIZE); + +static int arc_hl_mmap(struct file *fp, struct vm_area_struct *vma) +{ + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, + vma->vm_end - vma->vm_start, + vma->vm_page_prot)) { + pr_warn("Hostlink buffer mmap ERROR\n"); + return -EAGAIN; + } + return 0; +} + +static long arc_hl_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + /* we only support, returning the physical addr to mmap in user space */ + put_user((unsigned int)__HOSTLINK__, (int __user *)arg); + return 0; +} + +static const struct file_operations arc_hl_fops = { + .unlocked_ioctl = arc_hl_ioctl, + .mmap = arc_hl_mmap, +}; + +static struct miscdevice arc_hl_dev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "hostlink", + .fops = &arc_hl_fops +}; + +static int __init arc_hl_init(void) +{ + pr_info("ARC Hostlink driver mmap at 0x%p\n", __HOSTLINK__); + return misc_register(&arc_hl_dev); +} +module_init(arc_hl_init); diff --git a/arch/arc/kernel/arcksyms.c b/arch/arc/kernel/arcksyms.c new file mode 100644 index 000000000..8851c0a19 --- /dev/null +++ b/arch/arc/kernel/arcksyms.c @@ -0,0 +1,54 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * arcksyms.c - Exporting symbols not exportable from their own sources + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/module.h> + +/* libgcc functions, not part of kernel sources */ +extern void __ashldi3(void); +extern void __ashrdi3(void); +extern void __divsi3(void); +extern void __divsf3(void); +extern void __lshrdi3(void); +extern void __modsi3(void); +extern void __muldi3(void); +extern void __ucmpdi2(void); +extern void __udivsi3(void); +extern void __umodsi3(void); +extern void __cmpdi2(void); +extern void __fixunsdfsi(void); +extern void __muldf3(void); +extern void __divdf3(void); +extern void __floatunsidf(void); +extern void __floatunsisf(void); +extern void __udivdi3(void); + +EXPORT_SYMBOL(__ashldi3); +EXPORT_SYMBOL(__ashrdi3); +EXPORT_SYMBOL(__divsi3); +EXPORT_SYMBOL(__divsf3); +EXPORT_SYMBOL(__lshrdi3); +EXPORT_SYMBOL(__modsi3); +EXPORT_SYMBOL(__muldi3); +EXPORT_SYMBOL(__ucmpdi2); +EXPORT_SYMBOL(__udivsi3); +EXPORT_SYMBOL(__umodsi3); +EXPORT_SYMBOL(__cmpdi2); +EXPORT_SYMBOL(__fixunsdfsi); +EXPORT_SYMBOL(__muldf3); +EXPORT_SYMBOL(__divdf3); +EXPORT_SYMBOL(__floatunsidf); +EXPORT_SYMBOL(__floatunsisf); +EXPORT_SYMBOL(__udivdi3); + +/* ARC optimised assembler routines */ +EXPORT_SYMBOL(memset); +EXPORT_SYMBOL(memcpy); +EXPORT_SYMBOL(memcmp); +EXPORT_SYMBOL(strchr); +EXPORT_SYMBOL(strcpy); +EXPORT_SYMBOL(strcmp); +EXPORT_SYMBOL(strlen); diff --git a/arch/arc/kernel/asm-offsets.c b/arch/arc/kernel/asm-offsets.c new file mode 100644 index 000000000..0e884036a --- /dev/null +++ b/arch/arc/kernel/asm-offsets.c @@ -0,0 +1,84 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/thread_info.h> +#include <linux/kbuild.h> +#include <linux/ptrace.h> +#include <asm/hardirq.h> +#include <asm/page.h> + + +int main(void) +{ + DEFINE(TASK_THREAD, offsetof(struct task_struct, thread)); + DEFINE(TASK_THREAD_INFO, offsetof(struct task_struct, stack)); + + BLANK(); + + DEFINE(THREAD_KSP, offsetof(struct thread_struct, ksp)); + DEFINE(THREAD_CALLEE_REG, offsetof(struct thread_struct, callee_reg)); + DEFINE(THREAD_FAULT_ADDR, + offsetof(struct thread_struct, fault_address)); + + BLANK(); + + DEFINE(THREAD_INFO_FLAGS, offsetof(struct thread_info, flags)); + DEFINE(THREAD_INFO_PREEMPT_COUNT, + offsetof(struct thread_info, preempt_count)); + + BLANK(); + + DEFINE(TASK_ACT_MM, offsetof(struct task_struct, active_mm)); + DEFINE(TASK_TGID, offsetof(struct task_struct, tgid)); + DEFINE(TASK_PID, offsetof(struct task_struct, pid)); + DEFINE(TASK_COMM, offsetof(struct task_struct, comm)); + + DEFINE(MM_CTXT, offsetof(struct mm_struct, context)); + DEFINE(MM_PGD, offsetof(struct mm_struct, pgd)); + + DEFINE(MM_CTXT_ASID, offsetof(mm_context_t, asid)); + + BLANK(); + + DEFINE(PT_status32, offsetof(struct pt_regs, status32)); + DEFINE(PT_event, offsetof(struct pt_regs, event)); + DEFINE(PT_sp, offsetof(struct pt_regs, sp)); + DEFINE(PT_r0, offsetof(struct pt_regs, r0)); + DEFINE(PT_r1, offsetof(struct pt_regs, r1)); + DEFINE(PT_r2, offsetof(struct pt_regs, r2)); + DEFINE(PT_r3, offsetof(struct pt_regs, r3)); + DEFINE(PT_r4, offsetof(struct pt_regs, r4)); + DEFINE(PT_r5, offsetof(struct pt_regs, r5)); + DEFINE(PT_r6, offsetof(struct pt_regs, r6)); + DEFINE(PT_r7, offsetof(struct pt_regs, r7)); + DEFINE(PT_r8, offsetof(struct pt_regs, r8)); + DEFINE(PT_r10, offsetof(struct pt_regs, r10)); + DEFINE(PT_r26, offsetof(struct pt_regs, r26)); + DEFINE(PT_ret, offsetof(struct pt_regs, ret)); + DEFINE(PT_blink, offsetof(struct pt_regs, blink)); + DEFINE(PT_lpe, offsetof(struct pt_regs, lp_end)); + DEFINE(PT_lpc, offsetof(struct pt_regs, lp_count)); + DEFINE(PT_user_r25, offsetof(struct pt_regs, user_r25)); + + DEFINE(SZ_CALLEE_REGS, sizeof(struct callee_regs)); + DEFINE(SZ_PT_REGS, sizeof(struct pt_regs)); + +#ifdef CONFIG_ISA_ARCV2 + OFFSET(PT_r12, pt_regs, r12); + OFFSET(PT_r30, pt_regs, r30); +#endif +#ifdef CONFIG_ARC_HAS_ACCL_REGS + OFFSET(PT_r58, pt_regs, r58); + OFFSET(PT_r59, pt_regs, r59); +#endif +#ifdef CONFIG_ARC_DSP_SAVE_RESTORE_REGS + OFFSET(PT_DSP_CTRL, pt_regs, DSP_CTRL); +#endif + + return 0; +} diff --git a/arch/arc/kernel/ctx_sw.c b/arch/arc/kernel/ctx_sw.c new file mode 100644 index 000000000..1a76f2d6f --- /dev/null +++ b/arch/arc/kernel/ctx_sw.c @@ -0,0 +1,112 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * Vineetg: Aug 2009 + * -"C" version of lowest level context switch asm macro called by schedular + * gcc doesn't generate the dward CFI info for hand written asm, hence can't + * backtrace out of it (e.g. tasks sleeping in kernel). + * So we cheat a bit by writing almost similar code in inline-asm. + * -This is a hacky way of doing things, but there is no other simple way. + * I don't want/intend to extend unwinding code to understand raw asm + */ + +#include <asm/asm-offsets.h> +#include <linux/sched.h> +#include <linux/sched/debug.h> + +#define KSP_WORD_OFF ((TASK_THREAD + THREAD_KSP) / 4) + +struct task_struct *__sched +__switch_to(struct task_struct *prev_task, struct task_struct *next_task) +{ + unsigned int tmp; + unsigned int prev = (unsigned int)prev_task; + unsigned int next = (unsigned int)next_task; + + __asm__ __volatile__( + /* FP/BLINK save generated by gcc (standard function prologue */ + "st.a r13, [sp, -4] \n\t" + "st.a r14, [sp, -4] \n\t" + "st.a r15, [sp, -4] \n\t" + "st.a r16, [sp, -4] \n\t" + "st.a r17, [sp, -4] \n\t" + "st.a r18, [sp, -4] \n\t" + "st.a r19, [sp, -4] \n\t" + "st.a r20, [sp, -4] \n\t" + "st.a r21, [sp, -4] \n\t" + "st.a r22, [sp, -4] \n\t" + "st.a r23, [sp, -4] \n\t" + "st.a r24, [sp, -4] \n\t" +#ifndef CONFIG_ARC_CURR_IN_REG + "st.a r25, [sp, -4] \n\t" +#else + "sub sp, sp, 4 \n\t" /* usual r25 placeholder */ +#endif + + /* set ksp of outgoing task in tsk->thread.ksp */ +#if KSP_WORD_OFF <= 255 + "st.as sp, [%3, %1] \n\t" +#else + /* + * Workaround for NR_CPUS=4k + * %1 is bigger than 255 (S9 offset for st.as) + */ + "add2 r24, %3, %1 \n\t" + "st sp, [r24] \n\t" +#endif + + /* + * setup _current_task with incoming tsk. + * optionally, set r25 to that as well + * For SMP extra work to get to &_current_task[cpu] + * (open coded SET_CURR_TASK_ON_CPU) + */ +#ifndef CONFIG_SMP + "st %2, [@_current_task] \n\t" +#else + "lr r24, [identity] \n\t" + "lsr r24, r24, 8 \n\t" + "bmsk r24, r24, 7 \n\t" + "add2 r24, @_current_task, r24 \n\t" + "st %2, [r24] \n\t" +#endif +#ifdef CONFIG_ARC_CURR_IN_REG + "mov r25, %2 \n\t" +#endif + + /* get ksp of incoming task from tsk->thread.ksp */ + "ld.as sp, [%2, %1] \n\t" + + /* start loading it's CALLEE reg file */ + +#ifndef CONFIG_ARC_CURR_IN_REG + "ld.ab r25, [sp, 4] \n\t" +#else + "add sp, sp, 4 \n\t" +#endif + "ld.ab r24, [sp, 4] \n\t" + "ld.ab r23, [sp, 4] \n\t" + "ld.ab r22, [sp, 4] \n\t" + "ld.ab r21, [sp, 4] \n\t" + "ld.ab r20, [sp, 4] \n\t" + "ld.ab r19, [sp, 4] \n\t" + "ld.ab r18, [sp, 4] \n\t" + "ld.ab r17, [sp, 4] \n\t" + "ld.ab r16, [sp, 4] \n\t" + "ld.ab r15, [sp, 4] \n\t" + "ld.ab r14, [sp, 4] \n\t" + "ld.ab r13, [sp, 4] \n\t" + + /* last (ret value) = prev : although for ARC it mov r0, r0 */ + "mov %0, %3 \n\t" + + /* FP/BLINK restore generated by gcc (standard func epilogue */ + + : "=r"(tmp) + : "n"(KSP_WORD_OFF), "r"(next), "r"(prev) + : "blink" + ); + + return (struct task_struct *)tmp; +} diff --git a/arch/arc/kernel/ctx_sw_asm.S b/arch/arc/kernel/ctx_sw_asm.S new file mode 100644 index 000000000..02c461484 --- /dev/null +++ b/arch/arc/kernel/ctx_sw_asm.S @@ -0,0 +1,60 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * Vineetg: Aug 2009 + * -Moved core context switch macro out of entry.S into this file. + * -This is the more "natural" hand written assembler + */ + +#include <linux/linkage.h> +#include <asm/entry.h> /* For the SAVE_* macros */ +#include <asm/asm-offsets.h> + +#define KSP_WORD_OFF ((TASK_THREAD + THREAD_KSP) / 4) + +;################### Low Level Context Switch ########################## + + .section .sched.text,"ax",@progbits + .align 4 + .global __switch_to + .type __switch_to, @function +__switch_to: + CFI_STARTPROC + + /* Save regs on kernel mode stack of task */ + st.a blink, [sp, -4] + st.a fp, [sp, -4] + SAVE_CALLEE_SAVED_KERNEL + + /* Save the now KSP in task->thread.ksp */ +#if KSP_WORD_OFF <= 255 + st.as sp, [r0, KSP_WORD_OFF] +#else + /* Workaround for NR_CPUS=4k as ST.as can only take s9 offset */ + add2 r24, r0, KSP_WORD_OFF + st sp, [r24] +#endif + /* + * Return last task in r0 (return reg) + * On ARC, Return reg = First Arg reg = r0. + * Since we already have last task in r0, + * don't need to do anything special to return it + */ + + /* + * switch to new task, contained in r1 + * Temp reg r3 is required to get the ptr to store val + */ + SET_CURR_TASK_ON_CPU r1, r3 + + /* reload SP with kernel mode stack pointer in task->thread.ksp */ + ld.as sp, [r1, (TASK_THREAD + THREAD_KSP)/4] + + /* restore the registers */ + RESTORE_CALLEE_SAVED_KERNEL + ld.ab fp, [sp, 4] + ld.ab blink, [sp, 4] + j [blink] + +END_CFI(__switch_to) diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c new file mode 100644 index 000000000..721d465f1 --- /dev/null +++ b/arch/arc/kernel/devtree.c @@ -0,0 +1,75 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + * + * Based on reduced version of METAG + */ + + +#include <linux/init.h> +#include <linux/reboot.h> +#include <linux/memblock.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <asm/mach_desc.h> + +#ifdef CONFIG_SERIAL_EARLYCON + +static unsigned int __initdata arc_base_baud; + +unsigned int __init arc_early_base_baud(void) +{ + return arc_base_baud/16; +} + +static void __init arc_set_early_base_baud(unsigned long dt_root) +{ + if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x")) + arc_base_baud = 166666666; /* Fixed 166.6MHz clk (TB10x) */ + else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") || + of_flat_dt_is_compatible(dt_root, "snps,hsdk")) + arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x & HSDK) */ + else + arc_base_baud = 50000000; /* Fixed default 50MHz */ +} +#else +#define arc_set_early_base_baud(dt_root) +#endif + +static const void * __init arch_get_next_mach(const char *const **match) +{ + static const struct machine_desc *mdesc = __arch_info_begin; + const struct machine_desc *m = mdesc; + + if (m >= __arch_info_end) + return NULL; + + mdesc++; + *match = m->dt_compat; + return m; +} + +/** + * setup_machine_fdt - Machine setup when an dtb was passed to the kernel + * @dt: virtual address pointer to dt blob + * + * If a dtb was passed to the kernel, then use it to choose the correct + * machine_desc and to setup the system. + */ +const struct machine_desc * __init setup_machine_fdt(void *dt) +{ + const struct machine_desc *mdesc; + unsigned long dt_root; + + if (!early_init_dt_scan(dt)) + return NULL; + + mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach); + if (!mdesc) + machine_halt(); + + dt_root = of_get_flat_dt_root(); + arc_set_early_base_baud(dt_root); + + return mdesc; +} diff --git a/arch/arc/kernel/disasm.c b/arch/arc/kernel/disasm.c new file mode 100644 index 000000000..03f8b1be0 --- /dev/null +++ b/arch/arc/kernel/disasm.c @@ -0,0 +1,535 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * several functions that help interpret ARC instructions + * used for unaligned accesses, kprobes and kgdb + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/types.h> +#include <linux/kprobes.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <asm/disasm.h> + +#if defined(CONFIG_KGDB) || defined(CONFIG_ARC_EMUL_UNALIGNED) || \ + defined(CONFIG_KPROBES) + +/* disasm_instr: Analyses instruction at addr, stores + * findings in *state + */ +void __kprobes disasm_instr(unsigned long addr, struct disasm_state *state, + int userspace, struct pt_regs *regs, struct callee_regs *cregs) +{ + int fieldA = 0; + int fieldC = 0, fieldCisReg = 0; + uint16_t word1 = 0, word0 = 0; + int subopcode, is_linked, op_format; + uint16_t *ins_ptr; + uint16_t ins_buf[4]; + int bytes_not_copied = 0; + + memset(state, 0, sizeof(struct disasm_state)); + + /* This fetches the upper part of the 32 bit instruction + * in both the cases of Little Endian or Big Endian configurations. */ + if (userspace) { + bytes_not_copied = copy_from_user(ins_buf, + (const void __user *) addr, 8); + if (bytes_not_copied > 6) + goto fault; + ins_ptr = ins_buf; + } else { + ins_ptr = (uint16_t *) addr; + } + + word1 = *((uint16_t *)addr); + + state->major_opcode = (word1 >> 11) & 0x1F; + + /* Check if the instruction is 32 bit or 16 bit instruction */ + if (state->major_opcode < 0x0B) { + if (bytes_not_copied > 4) + goto fault; + state->instr_len = 4; + word0 = *((uint16_t *)(addr+2)); + state->words[0] = (word1 << 16) | word0; + } else { + state->instr_len = 2; + state->words[0] = word1; + } + + /* Read the second word in case of limm */ + word1 = *((uint16_t *)(addr + state->instr_len)); + word0 = *((uint16_t *)(addr + state->instr_len + 2)); + state->words[1] = (word1 << 16) | word0; + + switch (state->major_opcode) { + case op_Bcc: + state->is_branch = 1; + + /* unconditional branch s25, conditional branch s21 */ + fieldA = (IS_BIT(state->words[0], 16)) ? + FIELD_s25(state->words[0]) : + FIELD_s21(state->words[0]); + + state->delay_slot = IS_BIT(state->words[0], 5); + state->target = fieldA + (addr & ~0x3); + state->flow = direct_jump; + break; + + case op_BLcc: + if (IS_BIT(state->words[0], 16)) { + /* Branch and Link*/ + /* unconditional branch s25, conditional branch s21 */ + fieldA = (IS_BIT(state->words[0], 17)) ? + (FIELD_s25(state->words[0]) & ~0x3) : + FIELD_s21(state->words[0]); + + state->flow = direct_call; + } else { + /*Branch On Compare */ + fieldA = FIELD_s9(state->words[0]) & ~0x3; + state->flow = direct_jump; + } + + state->delay_slot = IS_BIT(state->words[0], 5); + state->target = fieldA + (addr & ~0x3); + state->is_branch = 1; + break; + + case op_LD: /* LD<zz> a,[b,s9] */ + state->write = 0; + state->di = BITS(state->words[0], 11, 11); + if (state->di) + break; + state->x = BITS(state->words[0], 6, 6); + state->zz = BITS(state->words[0], 7, 8); + state->aa = BITS(state->words[0], 9, 10); + state->wb_reg = FIELD_B(state->words[0]); + if (state->wb_reg == REG_LIMM) { + state->instr_len += 4; + state->aa = 0; + state->src1 = state->words[1]; + } else { + state->src1 = get_reg(state->wb_reg, regs, cregs); + } + state->src2 = FIELD_s9(state->words[0]); + state->dest = FIELD_A(state->words[0]); + state->pref = (state->dest == REG_LIMM); + break; + + case op_ST: + state->write = 1; + state->di = BITS(state->words[0], 5, 5); + if (state->di) + break; + state->aa = BITS(state->words[0], 3, 4); + state->zz = BITS(state->words[0], 1, 2); + state->src1 = FIELD_C(state->words[0]); + if (state->src1 == REG_LIMM) { + state->instr_len += 4; + state->src1 = state->words[1]; + } else { + state->src1 = get_reg(state->src1, regs, cregs); + } + state->wb_reg = FIELD_B(state->words[0]); + if (state->wb_reg == REG_LIMM) { + state->aa = 0; + state->instr_len += 4; + state->src2 = state->words[1]; + } else { + state->src2 = get_reg(state->wb_reg, regs, cregs); + } + state->src3 = FIELD_s9(state->words[0]); + break; + + case op_MAJOR_4: + subopcode = MINOR_OPCODE(state->words[0]); + switch (subopcode) { + case 32: /* Jcc */ + case 33: /* Jcc.D */ + case 34: /* JLcc */ + case 35: /* JLcc.D */ + is_linked = 0; + + if (subopcode == 33 || subopcode == 35) + state->delay_slot = 1; + + if (subopcode == 34 || subopcode == 35) + is_linked = 1; + + fieldCisReg = 0; + op_format = BITS(state->words[0], 22, 23); + if (op_format == 0 || ((op_format == 3) && + (!IS_BIT(state->words[0], 5)))) { + fieldC = FIELD_C(state->words[0]); + + if (fieldC == REG_LIMM) { + fieldC = state->words[1]; + state->instr_len += 4; + } else { + fieldCisReg = 1; + } + } else if (op_format == 1 || ((op_format == 3) + && (IS_BIT(state->words[0], 5)))) { + fieldC = FIELD_C(state->words[0]); + } else { + /* op_format == 2 */ + fieldC = FIELD_s12(state->words[0]); + } + + if (!fieldCisReg) { + state->target = fieldC; + state->flow = is_linked ? + direct_call : direct_jump; + } else { + state->target = get_reg(fieldC, regs, cregs); + state->flow = is_linked ? + indirect_call : indirect_jump; + } + state->is_branch = 1; + break; + + case 40: /* LPcc */ + if (BITS(state->words[0], 22, 23) == 3) { + /* Conditional LPcc u7 */ + fieldC = FIELD_C(state->words[0]); + + fieldC = fieldC << 1; + fieldC += (addr & ~0x03); + state->is_branch = 1; + state->flow = direct_jump; + state->target = fieldC; + } + /* For Unconditional lp, next pc is the fall through + * which is updated */ + break; + + case 48 ... 55: /* LD a,[b,c] */ + state->di = BITS(state->words[0], 15, 15); + if (state->di) + break; + state->x = BITS(state->words[0], 16, 16); + state->zz = BITS(state->words[0], 17, 18); + state->aa = BITS(state->words[0], 22, 23); + state->wb_reg = FIELD_B(state->words[0]); + if (state->wb_reg == REG_LIMM) { + state->instr_len += 4; + state->src1 = state->words[1]; + } else { + state->src1 = get_reg(state->wb_reg, regs, + cregs); + } + state->src2 = FIELD_C(state->words[0]); + if (state->src2 == REG_LIMM) { + state->instr_len += 4; + state->src2 = state->words[1]; + } else { + state->src2 = get_reg(state->src2, regs, + cregs); + } + state->dest = FIELD_A(state->words[0]); + if (state->dest == REG_LIMM) + state->pref = 1; + break; + + case 10: /* MOV */ + /* still need to check for limm to extract instr len */ + /* MOV is special case because it only takes 2 args */ + switch (BITS(state->words[0], 22, 23)) { + case 0: /* OP a,b,c */ + if (FIELD_C(state->words[0]) == REG_LIMM) + state->instr_len += 4; + break; + case 1: /* OP a,b,u6 */ + break; + case 2: /* OP b,b,s12 */ + break; + case 3: /* OP.cc b,b,c/u6 */ + if ((!IS_BIT(state->words[0], 5)) && + (FIELD_C(state->words[0]) == REG_LIMM)) + state->instr_len += 4; + break; + } + break; + + + default: + /* Not a Load, Jump or Loop instruction */ + /* still need to check for limm to extract instr len */ + switch (BITS(state->words[0], 22, 23)) { + case 0: /* OP a,b,c */ + if ((FIELD_B(state->words[0]) == REG_LIMM) || + (FIELD_C(state->words[0]) == REG_LIMM)) + state->instr_len += 4; + break; + case 1: /* OP a,b,u6 */ + break; + case 2: /* OP b,b,s12 */ + break; + case 3: /* OP.cc b,b,c/u6 */ + if ((!IS_BIT(state->words[0], 5)) && + ((FIELD_B(state->words[0]) == REG_LIMM) || + (FIELD_C(state->words[0]) == REG_LIMM))) + state->instr_len += 4; + break; + } + break; + } + break; + + /* 16 Bit Instructions */ + case op_LD_ADD: /* LD_S|LDB_S|LDW_S a,[b,c] */ + state->zz = BITS(state->words[0], 3, 4); + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src2 = get_reg(FIELD_S_C(state->words[0]), regs, cregs); + state->dest = FIELD_S_A(state->words[0]); + break; + + case op_ADD_MOV_CMP: + /* check for limm, ignore mov_s h,b (== mov_s 0,b) */ + if ((BITS(state->words[0], 3, 4) < 3) && + (FIELD_S_H(state->words[0]) == REG_LIMM)) + state->instr_len += 4; + break; + + case op_S: + subopcode = BITS(state->words[0], 5, 7); + switch (subopcode) { + case 0: /* j_s */ + case 1: /* j_s.d */ + case 2: /* jl_s */ + case 3: /* jl_s.d */ + state->target = get_reg(FIELD_S_B(state->words[0]), + regs, cregs); + state->delay_slot = subopcode & 1; + state->flow = (subopcode >= 2) ? + direct_call : indirect_jump; + break; + case 7: + switch (BITS(state->words[0], 8, 10)) { + case 4: /* jeq_s [blink] */ + case 5: /* jne_s [blink] */ + case 6: /* j_s [blink] */ + case 7: /* j_s.d [blink] */ + state->delay_slot = (subopcode == 7); + state->flow = indirect_jump; + state->target = get_reg(31, regs, cregs); + default: + break; + } + default: + break; + } + break; + + case op_LD_S: /* LD_S c, [b, u7] */ + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src2 = FIELD_S_u7(state->words[0]); + state->dest = FIELD_S_C(state->words[0]); + break; + + case op_LDB_S: + case op_STB_S: + /* no further handling required as byte accesses should not + * cause an unaligned access exception */ + state->zz = 1; + break; + + case op_LDWX_S: /* LDWX_S c, [b, u6] */ + state->x = 1; + fallthrough; + + case op_LDW_S: /* LDW_S c, [b, u6] */ + state->zz = 2; + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src2 = FIELD_S_u6(state->words[0]); + state->dest = FIELD_S_C(state->words[0]); + break; + + case op_ST_S: /* ST_S c, [b, u7] */ + state->write = 1; + state->src1 = get_reg(FIELD_S_C(state->words[0]), regs, cregs); + state->src2 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src3 = FIELD_S_u7(state->words[0]); + break; + + case op_STW_S: /* STW_S c,[b,u6] */ + state->write = 1; + state->zz = 2; + state->src1 = get_reg(FIELD_S_C(state->words[0]), regs, cregs); + state->src2 = get_reg(FIELD_S_B(state->words[0]), regs, cregs); + state->src3 = FIELD_S_u6(state->words[0]); + break; + + case op_SP: /* LD_S|LDB_S b,[sp,u7], ST_S|STB_S b,[sp,u7] */ + /* note: we are ignoring possibility of: + * ADD_S, SUB_S, PUSH_S, POP_S as these should not + * cause unaliged exception anyway */ + state->write = BITS(state->words[0], 6, 6); + state->zz = BITS(state->words[0], 5, 5); + if (state->zz) + break; /* byte accesses should not come here */ + if (!state->write) { + state->src1 = get_reg(28, regs, cregs); + state->src2 = FIELD_S_u7(state->words[0]); + state->dest = FIELD_S_B(state->words[0]); + } else { + state->src1 = get_reg(FIELD_S_B(state->words[0]), regs, + cregs); + state->src2 = get_reg(28, regs, cregs); + state->src3 = FIELD_S_u7(state->words[0]); + } + break; + + case op_GP: /* LD_S|LDB_S|LDW_S r0,[gp,s11/s9/s10] */ + /* note: ADD_S r0, gp, s11 is ignored */ + state->zz = BITS(state->words[0], 9, 10); + state->src1 = get_reg(26, regs, cregs); + state->src2 = state->zz ? FIELD_S_s10(state->words[0]) : + FIELD_S_s11(state->words[0]); + state->dest = 0; + break; + + case op_Pcl: /* LD_S b,[pcl,u10] */ + state->src1 = regs->ret & ~3; + state->src2 = FIELD_S_u10(state->words[0]); + state->dest = FIELD_S_B(state->words[0]); + break; + + case op_BR_S: + state->target = FIELD_S_s8(state->words[0]) + (addr & ~0x03); + state->flow = direct_jump; + state->is_branch = 1; + break; + + case op_B_S: + fieldA = (BITS(state->words[0], 9, 10) == 3) ? + FIELD_S_s7(state->words[0]) : + FIELD_S_s10(state->words[0]); + state->target = fieldA + (addr & ~0x03); + state->flow = direct_jump; + state->is_branch = 1; + break; + + case op_BL_S: + state->target = FIELD_S_s13(state->words[0]) + (addr & ~0x03); + state->flow = direct_call; + state->is_branch = 1; + break; + + default: + break; + } + + if (bytes_not_copied <= (8 - state->instr_len)) + return; + +fault: state->fault = 1; +} + +long __kprobes get_reg(int reg, struct pt_regs *regs, + struct callee_regs *cregs) +{ + long *p; + + if (reg <= 12) { + p = ®s->r0; + return p[-reg]; + } + + if (cregs && (reg <= 25)) { + p = &cregs->r13; + return p[13-reg]; + } + + if (reg == 26) + return regs->r26; + if (reg == 27) + return regs->fp; + if (reg == 28) + return regs->sp; + if (reg == 31) + return regs->blink; + + return 0; +} + +void __kprobes set_reg(int reg, long val, struct pt_regs *regs, + struct callee_regs *cregs) +{ + long *p; + + switch (reg) { + case 0 ... 12: + p = ®s->r0; + p[-reg] = val; + break; + case 13 ... 25: + if (cregs) { + p = &cregs->r13; + p[13-reg] = val; + } + break; + case 26: + regs->r26 = val; + break; + case 27: + regs->fp = val; + break; + case 28: + regs->sp = val; + break; + case 31: + regs->blink = val; + break; + default: + break; + } +} + +/* + * Disassembles the insn at @pc and sets @next_pc to next PC (which could be + * @pc +2/4/6 (ARCompact ISA allows free intermixing of 16/32 bit insns). + * + * If @pc is a branch + * -@tgt_if_br is set to branch target. + * -If branch has delay slot, @next_pc updated with actual next PC. + */ +int __kprobes disasm_next_pc(unsigned long pc, struct pt_regs *regs, + struct callee_regs *cregs, + unsigned long *next_pc, unsigned long *tgt_if_br) +{ + struct disasm_state instr; + + memset(&instr, 0, sizeof(struct disasm_state)); + disasm_instr(pc, &instr, 0, regs, cregs); + + *next_pc = pc + instr.instr_len; + + /* Instruction with possible two targets branch, jump and loop */ + if (instr.is_branch) + *tgt_if_br = instr.target; + + /* For the instructions with delay slots, the fall through is the + * instruction following the instruction in delay slot. + */ + if (instr.delay_slot) { + struct disasm_state instr_d; + + disasm_instr(*next_pc, &instr_d, 0, regs, cregs); + + *next_pc += instr_d.instr_len; + } + + /* Zero Overhead Loop - end of the loop */ + if (!(regs->status32 & STATUS32_L) && (*next_pc == regs->lp_end) + && (regs->lp_count > 1)) { + *next_pc = regs->lp_start; + } + + return instr.is_branch; +} + +#endif /* CONFIG_KGDB || CONFIG_ARC_EMUL_UNALIGNED || CONFIG_KPROBES */ diff --git a/arch/arc/kernel/entry-arcv2.S b/arch/arc/kernel/entry-arcv2.S new file mode 100644 index 000000000..12d5f12d1 --- /dev/null +++ b/arch/arc/kernel/entry-arcv2.S @@ -0,0 +1,263 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * ARCv2 ISA based core Low Level Intr/Traps/Exceptions(non-TLB) Handling + * + * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/linkage.h> /* ARC_{EXTRY,EXIT} */ +#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,TRAP...} */ +#include <asm/errno.h> +#include <asm/arcregs.h> +#include <asm/irqflags.h> + +; A maximum number of supported interrupts in the core interrupt controller. +; This number is not equal to the maximum interrupt number (256) because +; first 16 lines are reserved for exceptions and are not configurable. +#define NR_CPU_IRQS 240 + + .cpu HS + +#define VECTOR .word + +;############################ Vector Table ################################# + + .section .vector,"a",@progbits + .align 4 + +# Initial 16 slots are Exception Vectors +VECTOR res_service ; Reset Vector +VECTOR mem_service ; Mem exception +VECTOR instr_service ; Instrn Error +VECTOR EV_MachineCheck ; Fatal Machine check +VECTOR EV_TLBMissI ; Intruction TLB miss +VECTOR EV_TLBMissD ; Data TLB miss +VECTOR EV_TLBProtV ; Protection Violation +VECTOR EV_PrivilegeV ; Privilege Violation +VECTOR EV_SWI ; Software Breakpoint +VECTOR EV_Trap ; Trap exception +VECTOR EV_Extension ; Extn Instruction Exception +VECTOR EV_DivZero ; Divide by Zero +VECTOR EV_DCError ; Data Cache Error +VECTOR EV_Misaligned ; Misaligned Data Access +VECTOR reserved ; Reserved slots +VECTOR reserved ; Reserved slots + +# Begin Interrupt Vectors +VECTOR handle_interrupt ; (16) Timer0 +VECTOR handle_interrupt ; unused (Timer1) +VECTOR handle_interrupt ; unused (WDT) +VECTOR handle_interrupt ; (19) Inter core Interrupt (IPI) +VECTOR handle_interrupt ; (20) perf Interrupt +VECTOR handle_interrupt ; (21) Software Triggered Intr (Self IPI) +VECTOR handle_interrupt ; unused +VECTOR handle_interrupt ; (23) unused +# End of fixed IRQs + +.rept NR_CPU_IRQS - 8 + VECTOR handle_interrupt +.endr + + .section .text, "ax",@progbits + +reserved: + flag 1 ; Unexpected event, halt + +;##################### Interrupt Handling ############################## + +ENTRY(handle_interrupt) + + INTERRUPT_PROLOGUE + + # irq control APIs local_irq_save/restore/disable/enable fiddle with + # global interrupt enable bits in STATUS32 (.IE for 1 prio, .E[] for 2 prio) + # However a taken interrupt doesn't clear these bits. Thus irqs_disabled() + # query in hard ISR path would return false (since .IE is set) which would + # trips genirq interrupt handling asserts. + # + # So do a "soft" disable of interrutps here. + # + # Note this disable is only for consistent book-keeping as further interrupts + # will be disabled anyways even w/o this. Hardware tracks active interrupts + # seperately in AUX_IRQ_ACT.active and will not take new interrupts + # unless this one returns (or higher prio becomes pending in 2-prio scheme) + + IRQ_DISABLE + + ; icause is banked: one per priority level + ; so a higher prio interrupt taken here won't clobber prev prio icause + lr r0, [ICAUSE] + mov blink, ret_from_exception + + b.d arch_do_IRQ + mov r1, sp + +END(handle_interrupt) + +;################### Non TLB Exception Handling ############################# + +ENTRY(EV_SWI) + ; TODO: implement this + EXCEPTION_PROLOGUE + b ret_from_exception +END(EV_SWI) + +ENTRY(EV_DivZero) + ; TODO: implement this + EXCEPTION_PROLOGUE + b ret_from_exception +END(EV_DivZero) + +ENTRY(EV_DCError) + ; TODO: implement this + EXCEPTION_PROLOGUE + b ret_from_exception +END(EV_DCError) + +; --------------------------------------------- +; Memory Error Exception Handler +; - Unlike ARCompact, handles Bus errors for both User/Kernel mode, +; Instruction fetch or Data access, under a single Exception Vector +; --------------------------------------------- + +ENTRY(mem_service) + + EXCEPTION_PROLOGUE + + lr r0, [efa] + mov r1, sp + + FAKE_RET_FROM_EXCPN + + bl do_memory_error + b ret_from_exception +END(mem_service) + +ENTRY(EV_Misaligned) + + EXCEPTION_PROLOGUE + + lr r0, [efa] ; Faulting Data address + mov r1, sp + + FAKE_RET_FROM_EXCPN + + SAVE_CALLEE_SAVED_USER + mov r2, sp ; callee_regs + + bl do_misaligned_access + + ; TBD: optimize - do this only if a callee reg was involved + ; either a dst of emulated LD/ST or src with address-writeback + RESTORE_CALLEE_SAVED_USER + + b ret_from_exception +END(EV_Misaligned) + +; --------------------------------------------- +; Protection Violation Exception Handler +; --------------------------------------------- + +ENTRY(EV_TLBProtV) + + EXCEPTION_PROLOGUE + + lr r0, [efa] ; Faulting Data address + mov r1, sp ; pt_regs + + FAKE_RET_FROM_EXCPN + + mov blink, ret_from_exception + b do_page_fault + +END(EV_TLBProtV) + +; From Linux standpoint Slow Path I/D TLB Miss is same a ProtV as they +; need to call do_page_fault(). +; ECR in pt_regs provides whether access was R/W/X + +.global call_do_page_fault +.set call_do_page_fault, EV_TLBProtV + +;############# Common Handlers for ARCompact and ARCv2 ############## + +#include "entry.S" + +;############# Return from Intr/Excp/Trap (ARCv2 ISA Specifics) ############## +; +; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap) +; IRQ shd definitely not happen between now and rtie +; All 2 entry points to here already disable interrupts + +.Lrestore_regs: +restore_regs: + + # Interrpts are actually disabled from this point on, but will get + # reenabled after we return from interrupt/exception. + # But irq tracer needs to be told now... + TRACE_ASM_IRQ_ENABLE + + ld r0, [sp, PT_status32] ; U/K mode at time of entry + lr r10, [AUX_IRQ_ACT] + + bmsk r11, r10, 15 ; extract AUX_IRQ_ACT.active + breq r11, 0, .Lexcept_ret ; No intr active, ret from Exception + +;####### Return from Intr ####### + +.Lisr_ret: + +debug_marker_l1: + ; bbit1.nt r0, STATUS_DE_BIT, .Lintr_ret_to_delay_slot + btst r0, STATUS_DE_BIT ; Z flag set if bit clear + bnz .Lintr_ret_to_delay_slot ; branch if STATUS_DE_BIT set + + ; Handle special case #1: (Entry via Exception, Return via IRQ) + ; + ; Exception in U mode, preempted in kernel, Intr taken (K mode), orig + ; task now returning to U mode (riding the Intr) + ; AUX_IRQ_ACTIVE won't have U bit set (since intr in K mode), hence SP + ; won't be switched to correct U mode value (from AUX_SP) + ; So force AUX_IRQ_ACT.U for such a case + + btst r0, STATUS_U_BIT ; Z flag set if K (Z clear for U) + bset.nz r11, r11, AUX_IRQ_ACT_BIT_U ; NZ means U + sr r11, [AUX_IRQ_ACT] + + INTERRUPT_EPILOGUE + rtie + +;####### Return from Exception / pure kernel mode ####### + +.Lexcept_ret: ; Expects r0 has PT_status32 + +debug_marker_syscall: + EXCEPTION_EPILOGUE + rtie + +;####### Return from Intr to insn in delay slot ####### + +; Handle special case #2: (Entry via Exception in Delay Slot, Return via IRQ) +; +; Intr returning to a Delay Slot (DS) insn +; (since IRQ NOT allowed in DS in ARCv2, this can only happen if orig +; entry was via Exception in DS which got preempted in kernel). +; +; IRQ RTIE won't reliably restore DE bit and/or BTA, needs workaround +; +; Solution is to drop out of interrupt context into pure kernel mode +; and return from pure kernel mode which does right things for delay slot + +.Lintr_ret_to_delay_slot: +debug_marker_ds: + + ld r2, [@intr_to_DE_cnt] + add r2, r2, 1 + st r2, [@intr_to_DE_cnt] + + ; drop out of interrupt context (clear AUX_IRQ_ACT.active) + bmskn r11, r10, 15 + sr r11, [AUX_IRQ_ACT] + b .Lexcept_ret + +END(ret_from_exception) diff --git a/arch/arc/kernel/entry-compact.S b/arch/arc/kernel/entry-compact.S new file mode 100644 index 000000000..5cb0cd7e4 --- /dev/null +++ b/arch/arc/kernel/entry-compact.S @@ -0,0 +1,403 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARCompact ISA + * + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * vineetg: May 2011 + * -Userspace unaligned access emulation + * + * vineetg: Feb 2011 (ptrace low level code fixes) + * -traced syscall return code (r0) was not saved into pt_regs for restoring + * into user reg-file when traded task rets to user space. + * -syscalls needing arch-wrappers (mainly for passing sp as pt_regs) + * were not invoking post-syscall trace hook (jumping directly into + * ret_from_system_call) + * + * vineetg: Nov 2010: + * -Vector table jumps (@8 bytes) converted into branches (@4 bytes) + * -To maintain the slot size of 8 bytes/vector, added nop, which is + * not executed at runtime. + * + * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK) + * -do_signal()invoked upon TIF_RESTORE_SIGMASK as well + * -Wrappers for sys_{,rt_}sigsuspend() no longer needed as they don't + * need ptregs anymore + * + * Vineetg: Oct 2009 + * -In a rare scenario, Process gets a Priv-V exception and gets scheduled + * out. Since we don't do FAKE RTIE for Priv-V, CPU exception state remains + * active (AE bit enabled). This causes a double fault for a subseq valid + * exception. Thus FAKE RTIE needed in low level Priv-Violation handler. + * Instr Error could also cause similar scenario, so same there as well. + * + * Vineetg: March 2009 (Supporting 2 levels of Interrupts) + * + * Vineetg: Aug 28th 2008: Bug #94984 + * -Zero Overhead Loop Context shd be cleared when entering IRQ/EXcp/Trap + * Normally CPU does this automatically, however when doing FAKE rtie, + * we need to explicitly do this. The problem in macros + * FAKE_RET_FROM_EXCPN and FAKE_RET_FROM_EXCPN_LOCK_IRQ was that this bit + * was being "CLEARED" rather then "SET". Since it is Loop INHIBIT Bit, + * setting it and not clearing it clears ZOL context + * + * Vineetg: May 16th, 2008 + * - r25 now contains the Current Task when in kernel + * + * Vineetg: Dec 22, 2007 + * Minor Surgery of Low Level ISR to make it SMP safe + * - MMU_SCRATCH0 Reg used for freeing up r9 in Level 1 ISR + * - _current_task is made an array of NR_CPUS + * - Access of _current_task wrapped inside a macro so that if hardware + * team agrees for a dedicated reg, no other code is touched + * + * Amit Bhor, Rahul Trivedi, Kanika Nema, Sameer Dhavale : Codito Tech 2004 + */ + +#include <linux/errno.h> +#include <linux/linkage.h> /* {ENTRY,EXIT} */ +#include <asm/entry.h> +#include <asm/irqflags.h> + + .cpu A7 + +;############################ Vector Table ################################# + +.macro VECTOR lbl +#if 1 /* Just in case, build breaks */ + j \lbl +#else + b \lbl + nop +#endif +.endm + + .section .vector, "ax",@progbits + .align 4 + +/* Each entry in the vector table must occupy 2 words. Since it is a jump + * across sections (.vector to .text) we are guaranteed that 'j somewhere' + * will use the 'j limm' form of the instruction as long as somewhere is in + * a section other than .vector. + */ + +; ********* Critical System Events ********************** +VECTOR res_service ; 0x0, Reset Vector (0x0) +VECTOR mem_service ; 0x8, Mem exception (0x1) +VECTOR instr_service ; 0x10, Instrn Error (0x2) + +; ******************** Device ISRs ********************** +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS +VECTOR handle_interrupt_level2 +#else +VECTOR handle_interrupt_level1 +#endif + +.rept 28 +VECTOR handle_interrupt_level1 ; Other devices +.endr + +/* FOR ARC600: timer = 0x3, uart = 0x8, emac = 0x10 */ + +; ******************** Exceptions ********************** +VECTOR EV_MachineCheck ; 0x100, Fatal Machine check (0x20) +VECTOR EV_TLBMissI ; 0x108, Instruction TLB miss (0x21) +VECTOR EV_TLBMissD ; 0x110, Data TLB miss (0x22) +VECTOR EV_TLBProtV ; 0x118, Protection Violation (0x23) + ; or Misaligned Access +VECTOR EV_PrivilegeV ; 0x120, Privilege Violation (0x24) +VECTOR EV_Trap ; 0x128, Trap exception (0x25) +VECTOR EV_Extension ; 0x130, Extn Instruction Excp (0x26) + +.rept 24 +VECTOR reserved ; Reserved Exceptions +.endr + + +;##################### Scratch Mem for IRQ stack switching ############# + +ARCFP_DATA int1_saved_reg + .align 32 + .type int1_saved_reg, @object + .size int1_saved_reg, 4 +int1_saved_reg: + .zero 4 + +/* Each Interrupt level needs its own scratch */ +ARCFP_DATA int2_saved_reg + .type int2_saved_reg, @object + .size int2_saved_reg, 4 +int2_saved_reg: + .zero 4 + +; --------------------------------------------- + .section .text, "ax",@progbits + + +reserved: + flag 1 ; Unexpected event, halt + +;##################### Interrupt Handling ############################## + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS +; --------------------------------------------- +; Level 2 ISR: Can interrupt a Level 1 ISR +; --------------------------------------------- +ENTRY(handle_interrupt_level2) + + INTERRUPT_PROLOGUE 2 + + ;------------------------------------------------------ + ; if L2 IRQ interrupted a L1 ISR, disable preemption + ; + ; This is to avoid a potential L1-L2-L1 scenario + ; -L1 IRQ taken + ; -L2 interrupts L1 (before L1 ISR could run) + ; -preemption off IRQ, user task in syscall picked to run + ; -RTIE to userspace + ; Returns from L2 context fine + ; But both L1 and L2 re-enabled, so another L1 can be taken + ; while prev L1 is still unserviced + ; + ;------------------------------------------------------ + + ; L2 interrupting L1 implies both L2 and L1 active + ; However both A2 and A1 are NOT set in STATUS32, thus + ; need to check STATUS32_L2 to determine if L1 was active + + ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) + bbit0 r9, STATUS_A1_BIT, 1f ; L1 not active when L2 IRQ, so normal + + ; bump thread_info->preempt_count (Disable preemption) + GET_CURR_THR_INFO_FROM_SP r10 + ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] + add r9, r9, 1 + st r9, [r10, THREAD_INFO_PREEMPT_COUNT] + +1: + ;------------------------------------------------------ + ; setup params for Linux common ISR and invoke it + ;------------------------------------------------------ + lr r0, [icause2] + and r0, r0, 0x1f + + bl.d @arch_do_IRQ + mov r1, sp + + mov r8,0x2 + sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg + + b ret_from_exception + +END(handle_interrupt_level2) + +#endif + +; --------------------------------------------- +; User Mode Memory Bus Error Interrupt Handler +; (Kernel mode memory errors handled via separate exception vectors) +; --------------------------------------------- +ENTRY(mem_service) + + INTERRUPT_PROLOGUE 2 + + mov r0, ilink2 + mov r1, sp + + ; User process needs to be killed with SIGBUS, but first need to get + ; out of the L2 interrupt context (drop to pure kernel mode) and jump + ; off to "C" code where SIGBUS in enqueued + lr r3, [status32] + bclr r3, r3, STATUS_A2_BIT + or r3, r3, (STATUS_E1_MASK|STATUS_E2_MASK) + sr r3, [status32_l2] + mov ilink2, 1f + rtie +1: + bl do_memory_error + b ret_from_exception +END(mem_service) + +; --------------------------------------------- +; Level 1 ISR +; --------------------------------------------- +ENTRY(handle_interrupt_level1) + + INTERRUPT_PROLOGUE 1 + + lr r0, [icause1] + and r0, r0, 0x1f + +#ifdef CONFIG_TRACE_IRQFLAGS + ; icause1 needs to be read early, before calling tracing, which + ; can clobber scratch regs, hence use of stack to stash it + push r0 + TRACE_ASM_IRQ_DISABLE + pop r0 +#endif + + bl.d @arch_do_IRQ + mov r1, sp + + mov r8,0x1 + sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg + + b ret_from_exception +END(handle_interrupt_level1) + +;################### Non TLB Exception Handling ############################# + +; --------------------------------------------- +; Protection Violation Exception Handler +; --------------------------------------------- + +ENTRY(EV_TLBProtV) + + EXCEPTION_PROLOGUE + + mov r2, r10 ; ECR set into r10 already + lr r0, [efa] ; Faulting Data address (not part of pt_regs saved above) + + ; Exception auto-disables further Intr/exceptions. + ; Re-enable them by pretending to return from exception + ; (so rest of handler executes in pure K mode) + + FAKE_RET_FROM_EXCPN + + mov r1, sp ; Handle to pt_regs + + ;------ (5) Type of Protection Violation? ---------- + ; + ; ProtV Hardware Exception is triggered for Access Faults of 2 types + ; -Access Violation : 00_23_(00|01|02|03)_00 + ; x r w r+w + ; -Unaligned Access : 00_23_04_00 + ; + bbit1 r2, ECR_C_BIT_PROTV_MISALIG_DATA, 4f + + ;========= (6a) Access Violation Processing ======== + bl do_page_fault + b ret_from_exception + + ;========== (6b) Non aligned access ============ +4: + + SAVE_CALLEE_SAVED_USER + mov r2, sp ; callee_regs + + bl do_misaligned_access + + ; TBD: optimize - do this only if a callee reg was involved + ; either a dst of emulated LD/ST or src with address-writeback + RESTORE_CALLEE_SAVED_USER + + b ret_from_exception + +END(EV_TLBProtV) + +; Wrapper for Linux page fault handler called from EV_TLBMiss* +; Very similar to ProtV handler case (6a) above, but avoids the extra checks +; for Misaligned access +; +ENTRY(call_do_page_fault) + + EXCEPTION_PROLOGUE + lr r0, [efa] ; Faulting Data address + mov r1, sp + FAKE_RET_FROM_EXCPN + + mov blink, ret_from_exception + b do_page_fault + +END(call_do_page_fault) + +;############# Common Handlers for ARCompact and ARCv2 ############## + +#include "entry.S" + +;############# Return from Intr/Excp/Trap (ARC Specifics) ############## +; +; Restore the saved sys context (common exit-path for EXCPN/IRQ/Trap) +; IRQ shd definitely not happen between now and rtie +; All 2 entry points to here already disable interrupts + +.Lrestore_regs: + + # Interrupts are actually disabled from this point on, but will get + # reenabled after we return from interrupt/exception. + # But irq tracer needs to be told now... + TRACE_ASM_IRQ_ENABLE + + lr r10, [status32] + + ; Restore REG File. In case multiple Events outstanding, + ; use the same priority as rtie: EXCPN, L2 IRQ, L1 IRQ, None + ; Note that we use realtime STATUS32 (not pt_regs->status32) to + ; decide that. + + and.f 0, r10, (STATUS_A1_MASK|STATUS_A2_MASK) + bz .Lexcep_or_pure_K_ret + + ; Returning from Interrupts (Level 1 or 2) + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS + + ; Level 2 interrupt return Path - from hardware standpoint + bbit0 r10, STATUS_A2_BIT, not_level2_interrupt + + ;------------------------------------------------------------------ + ; However the context returning might not have taken L2 intr itself + ; e.g. Task'A' user-code -> L2 intr -> schedule -> 'B' user-code ret + ; Special considerations needed for the context which took L2 intr + + ld r9, [sp, PT_event] ; Ensure this is L2 intr context + brne r9, event_IRQ2, 149f + + ;------------------------------------------------------------------ + ; if L2 IRQ interrupted an L1 ISR, we'd disabled preemption earlier + ; so that sched doesn't move to new task, causing L1 to be delayed + ; undeterministically. Now that we've achieved that, let's reset + ; things to what they were, before returning from L2 context + ;---------------------------------------------------------------- + + ld r9, [sp, PT_status32] ; get statu32_l2 (saved in pt_regs) + bbit0 r9, STATUS_A1_BIT, 149f ; L1 not active when L2 IRQ, so normal + + ; decrement thread_info->preempt_count (re-enable preemption) + GET_CURR_THR_INFO_FROM_SP r10 + ld r9, [r10, THREAD_INFO_PREEMPT_COUNT] + + ; paranoid check, given A1 was active when A2 happened, preempt count + ; must not be 0 because we would have incremented it. + ; If this does happen we simply HALT as it means a BUG !!! + cmp r9, 0 + bnz 2f + flag 1 + +2: + sub r9, r9, 1 + st r9, [r10, THREAD_INFO_PREEMPT_COUNT] + +149: + INTERRUPT_EPILOGUE 2 ; return from level 2 interrupt +debug_marker_l2: + rtie + +not_level2_interrupt: + +#endif + + INTERRUPT_EPILOGUE 1 ; return from level 1 interrupt +debug_marker_l1: + rtie + +.Lexcep_or_pure_K_ret: + + ;this case is for syscalls or Exceptions or pure kernel mode + + EXCEPTION_EPILOGUE +debug_marker_syscall: + rtie + +END(ret_from_exception) diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S new file mode 100644 index 000000000..6ee9cb559 --- /dev/null +++ b/arch/arc/kernel/entry.S @@ -0,0 +1,372 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Common Low Level Interrupts/Traps/Exceptions(non-TLB) Handling for ARC + * (included from entry-<isa>.S + * + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +/*------------------------------------------------------------------ + * Function ABI + *------------------------------------------------------------------ + * + * Arguments r0 - r7 + * Caller Saved Registers r0 - r12 + * Callee Saved Registers r13- r25 + * Global Pointer (gp) r26 + * Frame Pointer (fp) r27 + * Stack Pointer (sp) r28 + * Branch link register (blink) r31 + *------------------------------------------------------------------ + */ + +;################### Special Sys Call Wrappers ########################## + +ENTRY(sys_clone_wrapper) + SAVE_CALLEE_SAVED_USER + bl @sys_clone + DISCARD_CALLEE_SAVED_USER + + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys_exit + + b .Lret_from_system_call +END(sys_clone_wrapper) + +ENTRY(sys_clone3_wrapper) + SAVE_CALLEE_SAVED_USER + bl @sys_clone3 + DISCARD_CALLEE_SAVED_USER + + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys_exit + + b .Lret_from_system_call +END(sys_clone3_wrapper) + +ENTRY(ret_from_fork) + ; when the forked child comes here from the __switch_to function + ; r0 has the last task pointer. + ; put last task in scheduler queue + jl @schedule_tail + + ld r9, [sp, PT_status32] + brne r9, 0, 1f + + jl.d [r14] ; kernel thread entry point + mov r0, r13 ; (see PF_KTHREAD block in copy_thread) + +1: + ; Return to user space + ; 1. Any forked task (Reach here via BRne above) + ; 2. First ever init task (Reach here via return from JL above) + ; This is the historic "kernel_execve" use-case, to return to init + ; user mode, in a round about way since that is always done from + ; a kernel thread which is executed via JL above but always returns + ; out whenever kernel_execve (now inline do_fork()) is involved + b ret_from_exception +END(ret_from_fork) + +;################### Non TLB Exception Handling ############################# + +; --------------------------------------------- +; Instruction Error Exception Handler +; --------------------------------------------- + +ENTRY(instr_service) + + EXCEPTION_PROLOGUE + + lr r0, [efa] + mov r1, sp + + FAKE_RET_FROM_EXCPN + + bl do_insterror_or_kprobe + b ret_from_exception +END(instr_service) + +; --------------------------------------------- +; Machine Check Exception Handler +; --------------------------------------------- + +ENTRY(EV_MachineCheck) + + EXCEPTION_PROLOGUE + + lr r2, [ecr] + lr r0, [efa] + mov r1, sp + + ; hardware auto-disables MMU, re-enable it to allow kernel vaddr + ; access for say stack unwinding of modules for crash dumps + lr r3, [ARC_REG_PID] + or r3, r3, MMU_ENABLE + sr r3, [ARC_REG_PID] + + lsr r3, r2, 8 + bmsk r3, r3, 7 + brne r3, ECR_C_MCHK_DUP_TLB, 1f + + bl do_tlb_overlap_fault + b ret_from_exception + +1: + ; DEAD END: can't do much, display Regs and HALT + SAVE_CALLEE_SAVED_USER + + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10 + st sp, [r10, THREAD_CALLEE_REG] + + j do_machine_check_fault + +END(EV_MachineCheck) + +; --------------------------------------------- +; Privilege Violation Exception Handler +; --------------------------------------------- +ENTRY(EV_PrivilegeV) + + EXCEPTION_PROLOGUE + + lr r0, [efa] + mov r1, sp + + FAKE_RET_FROM_EXCPN + + bl do_privilege_fault + b ret_from_exception +END(EV_PrivilegeV) + +; --------------------------------------------- +; Extension Instruction Exception Handler +; --------------------------------------------- +ENTRY(EV_Extension) + + EXCEPTION_PROLOGUE + + lr r0, [efa] + mov r1, sp + + FAKE_RET_FROM_EXCPN + + bl do_extension_fault + b ret_from_exception +END(EV_Extension) + +;################ Trap Handling (Syscall, Breakpoint) ################## + +; --------------------------------------------- +; syscall Tracing +; --------------------------------------------- +tracesys: + ; save EFA in case tracer wants the PC of traced task + ; using ERET won't work since next-PC has already committed + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r11 + st r12, [r11, THREAD_FAULT_ADDR] ; thread.fault_address + + ; PRE Sys Call Ptrace hook + mov r0, sp ; pt_regs needed + bl @syscall_trace_entry + + ; Tracing code now returns the syscall num (orig or modif) + mov r8, r0 + + ; Do the Sys Call as we normally would. + ; Validate the Sys Call number + cmp r8, NR_syscalls - 1 + mov.hi r0, -ENOSYS + bhi tracesys_exit + + ; Restore the sys-call args. Mere invocation of the hook abv could have + ; clobbered them (since they are in scratch regs). The tracer could also + ; have deliberately changed the syscall args: r0-r7 + ld r0, [sp, PT_r0] + ld r1, [sp, PT_r1] + ld r2, [sp, PT_r2] + ld r3, [sp, PT_r3] + ld r4, [sp, PT_r4] + ld r5, [sp, PT_r5] + ld r6, [sp, PT_r6] + ld r7, [sp, PT_r7] + ld.as r9, [sys_call_table, r8] + jl [r9] ; Entry into Sys Call Handler + +tracesys_exit: + st r0, [sp, PT_r0] ; sys call return value in pt_regs + + ;POST Sys Call Ptrace Hook + mov r0, sp ; pt_regs needed + bl @syscall_trace_exit + b ret_from_exception ; NOT ret_from_system_call at is saves r0 which + ; we'd done before calling post hook above + +; --------------------------------------------- +; Breakpoint TRAP +; --------------------------------------------- +trap_with_param: + mov r0, r12 ; EFA in case ptracer/gdb wants stop_pc + mov r1, sp + + ; Save callee regs in case gdb wants to have a look + ; SP will grow up by size of CALLEE Reg-File + ; NOTE: clobbers r12 + SAVE_CALLEE_SAVED_USER + + ; save location of saved Callee Regs @ thread_struct->pc + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10 + st sp, [r10, THREAD_CALLEE_REG] + + ; Call the trap handler + bl do_non_swi_trap + + ; unwind stack to discard Callee saved Regs + DISCARD_CALLEE_SAVED_USER + + b ret_from_exception + +; --------------------------------------------- +; syscall TRAP +; ABI: (r0-r7) upto 8 args, (r8) syscall number +; --------------------------------------------- + +ENTRY(EV_Trap) + + EXCEPTION_PROLOGUE + + lr r12, [efa] + + FAKE_RET_FROM_EXCPN + + ;============ TRAP 1 :breakpoints + ; Check ECR for trap with arg (PROLOGUE ensures r10 has ECR) + bmsk.f 0, r10, 7 + bnz trap_with_param + + ;============ TRAP (no param): syscall top level + + ; If syscall tracing ongoing, invoke pre-post-hooks + GET_CURR_THR_INFO_FLAGS r10 + btst r10, TIF_SYSCALL_TRACE + bnz tracesys ; this never comes back + + ;============ Normal syscall case + + ; syscall num shd not exceed the total system calls avail + cmp r8, NR_syscalls - 1 + mov.hi r0, -ENOSYS + bhi .Lret_from_system_call + + ; Offset into the syscall_table and call handler + ld.as r9,[sys_call_table, r8] + jl [r9] ; Entry into Sys Call Handler + +.Lret_from_system_call: + + st r0, [sp, PT_r0] ; sys call return value in pt_regs + + ; fall through to ret_from_exception +END(EV_Trap) + +;############# Return from Intr/Excp/Trap (Linux Specifics) ############## +; +; If ret to user mode do we need to handle signals, schedule() et al. + +ENTRY(ret_from_exception) + + ; Pre-{IRQ,Trap,Exception} K/U mode from pt_regs->status32 + ld r8, [sp, PT_status32] ; returning to User/Kernel Mode + + bbit0 r8, STATUS_U_BIT, resume_kernel_mode + + ; Before returning to User mode check-for-and-complete any pending work + ; such as rescheduling/signal-delivery etc. +resume_user_mode_begin: + + ; Disable IRQs to ensures that chk for pending work itself is atomic + ; (and we don't end up missing a NEED_RESCHED/SIGPENDING due to an + ; interim IRQ). + IRQ_DISABLE r10 + + ; Fast Path return to user mode if no pending work + GET_CURR_THR_INFO_FLAGS r9 + and.f 0, r9, _TIF_WORK_MASK + bz .Lrestore_regs + + ; --- (Slow Path #1) task preemption --- + bbit0 r9, TIF_NEED_RESCHED, .Lchk_pend_signals + mov blink, resume_user_mode_begin ; tail-call to U mode ret chks + j @schedule ; BTST+Bnz causes relo error in link + +.Lchk_pend_signals: + IRQ_ENABLE r10 + + ; --- (Slow Path #2) pending signal --- + mov r0, sp ; pt_regs for arg to do_signal()/do_notify_resume() + + GET_CURR_THR_INFO_FLAGS r9 + and.f 0, r9, _TIF_SIGPENDING|_TIF_NOTIFY_SIGNAL + bz .Lchk_notify_resume + + ; Normal Trap/IRQ entry only saves Scratch (caller-saved) regs + ; in pt_reg since the "C" ABI (kernel code) will automatically + ; save/restore callee-saved regs. + ; + ; However, here we need to explicitly save callee regs because + ; (i) If this signal causes coredump - full regfile needed + ; (ii) If signal is SIGTRAP/SIGSTOP, task is being traced thus + ; tracer might call PEEKUSR(CALLEE reg) + ; + ; NOTE: SP will grow up by size of CALLEE Reg-File + SAVE_CALLEE_SAVED_USER ; clobbers r12 + + ; save location of saved Callee Regs @ thread_struct->callee + GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10 + st sp, [r10, THREAD_CALLEE_REG] + + bl @do_signal + + ; Ideally we want to discard the Callee reg above, however if this was + ; a tracing signal, tracer could have done a POKEUSR(CALLEE reg) + RESTORE_CALLEE_SAVED_USER + + b resume_user_mode_begin ; loop back to start of U mode ret + + ; --- (Slow Path #3) notify_resume --- +.Lchk_notify_resume: + btst r9, TIF_NOTIFY_RESUME + blnz @do_notify_resume + b resume_user_mode_begin ; unconditionally back to U mode ret chks + ; for single exit point from this block + +resume_kernel_mode: + + ; Disable Interrupts from this point on + ; CONFIG_PREEMPTION: This is a must for preempt_schedule_irq() + ; !CONFIG_PREEMPTION: To ensure restore_regs is intr safe + IRQ_DISABLE r9 + +#ifdef CONFIG_PREEMPTION + + ; Can't preempt if preemption disabled + GET_CURR_THR_INFO_FROM_SP r10 + ld r8, [r10, THREAD_INFO_PREEMPT_COUNT] + brne r8, 0, .Lrestore_regs + + ; check if this task's NEED_RESCHED flag set + ld r9, [r10, THREAD_INFO_FLAGS] + bbit0 r9, TIF_NEED_RESCHED, .Lrestore_regs + + ; Invoke PREEMPTION + jl preempt_schedule_irq + + ; preempt_schedule_irq() always returns with IRQ disabled +#endif + + b .Lrestore_regs + +##### DONT ADD CODE HERE - .Lrestore_regs actually follows in entry-<isa>.S + diff --git a/arch/arc/kernel/fpu.c b/arch/arc/kernel/fpu.c new file mode 100644 index 000000000..ec640219d --- /dev/null +++ b/arch/arc/kernel/fpu.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * fpu.c - save/restore of Floating Point Unit Registers on task switch + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/sched.h> +#include <asm/fpu.h> + +#ifdef CONFIG_ISA_ARCOMPACT + +/* + * To save/restore FPU regs, simplest scheme would use LR/SR insns. + * However since SR serializes the pipeline, an alternate "hack" can be used + * which uses the FPU Exchange insn (DEXCL) to r/w FPU regs. + * + * Store to 64bit dpfp1 reg from a pair of core regs: + * dexcl1 0, r1, r0 ; where r1:r0 is the 64 bit val + * + * Read from dpfp1 into pair of core regs (w/o clobbering dpfp1) + * mov_s r3, 0 + * daddh11 r1, r3, r3 ; get "hi" into r1 (dpfp1 unchanged) + * dexcl1 r0, r1, r3 ; get "low" into r0 (dpfp1 low clobbered) + * dexcl1 0, r1, r0 ; restore dpfp1 to orig value + * + * However we can tweak the read, so that read-out of outgoing task's FPU regs + * and write of incoming task's regs happen in one shot. So all the work is + * done before context switch + */ + +void fpu_save_restore(struct task_struct *prev, struct task_struct *next) +{ + unsigned int *saveto = &prev->thread.fpu.aux_dpfp[0].l; + unsigned int *readfrom = &next->thread.fpu.aux_dpfp[0].l; + + const unsigned int zero = 0; + + __asm__ __volatile__( + "daddh11 %0, %2, %2\n" + "dexcl1 %1, %3, %4\n" + : "=&r" (*(saveto + 1)), /* early clobber must here */ + "=&r" (*(saveto)) + : "r" (zero), "r" (*(readfrom + 1)), "r" (*(readfrom)) + ); + + __asm__ __volatile__( + "daddh22 %0, %2, %2\n" + "dexcl2 %1, %3, %4\n" + : "=&r"(*(saveto + 3)), /* early clobber must here */ + "=&r"(*(saveto + 2)) + : "r" (zero), "r" (*(readfrom + 3)), "r" (*(readfrom + 2)) + ); +} + +#else + +void fpu_init_task(struct pt_regs *regs) +{ + const unsigned int fwe = 0x80000000; + + /* default rounding mode */ + write_aux_reg(ARC_REG_FPU_CTRL, 0x100); + + /* Initialize to zero: setting requires FWE be set */ + write_aux_reg(ARC_REG_FPU_STATUS, fwe); +} + +void fpu_save_restore(struct task_struct *prev, struct task_struct *next) +{ + struct arc_fpu *save = &prev->thread.fpu; + struct arc_fpu *restore = &next->thread.fpu; + const unsigned int fwe = 0x80000000; + + save->ctrl = read_aux_reg(ARC_REG_FPU_CTRL); + save->status = read_aux_reg(ARC_REG_FPU_STATUS); + + write_aux_reg(ARC_REG_FPU_CTRL, restore->ctrl); + write_aux_reg(ARC_REG_FPU_STATUS, (fwe | restore->status)); +} + +#endif diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S new file mode 100644 index 000000000..915278244 --- /dev/null +++ b/arch/arc/kernel/head.S @@ -0,0 +1,173 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * ARC CPU startup Code + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * Vineetg: Dec 2007 + * -Check if we are running on Simulator or on real hardware + * to skip certain things during boot on simulator + */ + +#include <linux/linkage.h> +#include <asm/asm-offsets.h> +#include <asm/entry.h> +#include <asm/arcregs.h> +#include <asm/cache.h> +#include <asm/dsp-impl.h> +#include <asm/irqflags.h> + +.macro CPU_EARLY_SETUP + + ; Setting up Vectror Table (in case exception happens in early boot + sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE] + + ; Disable I-cache/D-cache if kernel so configured + lr r5, [ARC_REG_IC_BCR] + breq r5, 0, 1f ; I$ doesn't exist + lr r5, [ARC_REG_IC_CTRL] +#ifdef CONFIG_ARC_HAS_ICACHE + bclr r5, r5, 0 ; 0 - Enable, 1 is Disable +#else + bset r5, r5, 0 ; I$ exists, but is not used +#endif + sr r5, [ARC_REG_IC_CTRL] + +1: + lr r5, [ARC_REG_DC_BCR] + breq r5, 0, 1f ; D$ doesn't exist + lr r5, [ARC_REG_DC_CTRL] + bclr r5, r5, 6 ; Invalidate (discard w/o wback) +#ifdef CONFIG_ARC_HAS_DCACHE + bclr r5, r5, 0 ; Enable (+Inv) +#else + bset r5, r5, 0 ; Disable (+Inv) +#endif + sr r5, [ARC_REG_DC_CTRL] + +1: + +#ifdef CONFIG_ISA_ARCV2 + ; Unaligned access is disabled at reset, so re-enable early as + ; gcc 7.3.1 (ARC GNU 2018.03) onwards generates unaligned access + ; by default + lr r5, [status32] +#ifdef CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS + bset r5, r5, STATUS_AD_BIT +#else + ; Although disabled at reset, bootloader might have enabled it + bclr r5, r5, STATUS_AD_BIT +#endif + kflag r5 + +#ifdef CONFIG_ARC_LPB_DISABLE + lr r5, [ARC_REG_LPB_BUILD] + breq r5, 0, 1f ; LPB doesn't exist + mov r5, 1 + sr r5, [ARC_REG_LPB_CTRL] +1: +#endif /* CONFIG_ARC_LPB_DISABLE */ + + /* On HSDK, CCMs need to remapped super early */ +#ifdef CONFIG_ARC_SOC_HSDK + mov r6, 0x60000000 + lr r5, [ARC_REG_ICCM_BUILD] + breq r5, 0, 1f + sr r6, [ARC_REG_AUX_ICCM] +1: + lr r5, [ARC_REG_DCCM_BUILD] + breq r5, 0, 2f + sr r6, [ARC_REG_AUX_DCCM] +2: +#endif /* CONFIG_ARC_SOC_HSDK */ + +#endif /* CONFIG_ISA_ARCV2 */ + + ; Config DSP_CTRL properly, so kernel may use integer multiply, + ; multiply-accumulate, and divide operations + DSP_EARLY_INIT +.endm + + .section .init.text, "ax",@progbits + +;---------------------------------------------------------------- +; Default Reset Handler (jumped into from Reset vector) +; - Don't clobber r0,r1,r2 as they might have u-boot provided args +; - Platforms can override this weak version if needed +;---------------------------------------------------------------- +WEAK(res_service) + j stext +END(res_service) + +;---------------------------------------------------------------- +; Kernel Entry point +;---------------------------------------------------------------- +ENTRY(stext) + + CPU_EARLY_SETUP + +#ifdef CONFIG_SMP + GET_CPU_ID r5 + cmp r5, 0 + mov.nz r0, r5 + bz .Lmaster_proceed + + ; Non-Masters wait for Master to boot enough and bring them up + ; when they resume, tail-call to entry point + mov blink, @first_lines_of_secondary + j arc_platform_smp_wait_to_boot + +.Lmaster_proceed: +#endif + + ; Clear BSS before updating any globals + ; XXX: use ZOL here + mov r5, __bss_start + sub r6, __bss_stop, r5 + lsr.f lp_count, r6, 2 + lpnz 1f + st.ab 0, [r5, 4] +1: + + ; Uboot - kernel ABI + ; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2 + ; r1 = magic number (always zero as of now) + ; r2 = pointer to uboot provided cmdline or external DTB in mem + ; These are handled later in handle_uboot_args() + st r0, [@uboot_tag] + st r1, [@uboot_magic] + st r2, [@uboot_arg] + + ; setup "current" tsk and optionally cache it in dedicated r25 + mov r9, @init_task + SET_CURR_TASK_ON_CPU r9, r0 ; r9 = tsk, r0 = scratch + + ; setup stack (fp, sp) + mov fp, 0 + + ; tsk->thread_info is really a PAGE, whose bottom hoists stack + GET_TSK_STACK_BASE r9, sp ; r9 = tsk, sp = stack base(output) + + j start_kernel ; "C" entry point +END(stext) + +#ifdef CONFIG_SMP +;---------------------------------------------------------------- +; First lines of code run by secondary before jumping to 'C' +;---------------------------------------------------------------- + .section .text, "ax",@progbits +ENTRY(first_lines_of_secondary) + + ; setup per-cpu idle task as "current" on this CPU + ld r0, [@secondary_idle_tsk] + SET_CURR_TASK_ON_CPU r0, r1 + + ; setup stack (fp, sp) + mov fp, 0 + + ; set it's stack base to tsk->thread_info bottom + GET_TSK_STACK_BASE r0, sp + + j start_kernel_secondary +END(first_lines_of_secondary) +#endif diff --git a/arch/arc/kernel/intc-arcv2.c b/arch/arc/kernel/intc-arcv2.c new file mode 100644 index 000000000..5cda19d0a --- /dev/null +++ b/arch/arc/kernel/intc-arcv2.c @@ -0,0 +1,191 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2014 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/irqdomain.h> +#include <linux/irqchip.h> +#include <asm/irq.h> + +#define NR_EXCEPTIONS 16 + +struct bcr_irq_arcv2 { +#ifdef CONFIG_CPU_BIG_ENDIAN + unsigned int pad:3, firq:1, prio:4, exts:8, irqs:8, ver:8; +#else + unsigned int ver:8, irqs:8, exts:8, prio:4, firq:1, pad:3; +#endif +}; + +/* + * Early Hardware specific Interrupt setup + * -Called very early (start_kernel -> setup_arch -> setup_processor) + * -Platform Independent (must for any ARC Core) + * -Needed for each CPU (hence not foldable into init_IRQ) + */ +void arc_init_IRQ(void) +{ + unsigned int tmp, irq_prio, i; + struct bcr_irq_arcv2 irq_bcr; + + struct aux_irq_ctrl { +#ifdef CONFIG_CPU_BIG_ENDIAN + unsigned int res3:18, save_idx_regs:1, res2:1, + save_u_to_u:1, save_lp_regs:1, save_blink:1, + res:4, save_nr_gpr_pairs:5; +#else + unsigned int save_nr_gpr_pairs:5, res:4, + save_blink:1, save_lp_regs:1, save_u_to_u:1, + res2:1, save_idx_regs:1, res3:18; +#endif + } ictrl; + + *(unsigned int *)&ictrl = 0; + +#ifndef CONFIG_ARC_IRQ_NO_AUTOSAVE + ictrl.save_nr_gpr_pairs = 6; /* r0 to r11 (r12 saved manually) */ + ictrl.save_blink = 1; + ictrl.save_lp_regs = 1; /* LP_COUNT, LP_START, LP_END */ + ictrl.save_u_to_u = 0; /* user ctxt saved on kernel stack */ + ictrl.save_idx_regs = 1; /* JLI, LDI, EI */ +#endif + + WRITE_AUX(AUX_IRQ_CTRL, ictrl); + + /* + * ARCv2 core intc provides multiple interrupt priorities (upto 16). + * Typical builds though have only two levels (0-high, 1-low) + * Linux by default uses lower prio 1 for most irqs, reserving 0 for + * NMI style interrupts in future (say perf) + */ + + READ_BCR(ARC_REG_IRQ_BCR, irq_bcr); + + irq_prio = irq_bcr.prio; /* Encoded as N-1 for N levels */ + pr_info("archs-intc\t: %d priority levels (default %d)%s\n", + irq_prio + 1, ARCV2_IRQ_DEF_PRIO, + irq_bcr.firq ? " FIRQ (not used)":""); + + /* + * Set a default priority for all available interrupts to prevent + * switching of register banks if Fast IRQ and multiple register banks + * are supported by CPU. + * Also disable private-per-core IRQ lines so faulty external HW won't + * trigger interrupt that kernel is not ready to handle. + */ + for (i = NR_EXCEPTIONS; i < irq_bcr.irqs + NR_EXCEPTIONS; i++) { + write_aux_reg(AUX_IRQ_SELECT, i); + write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO); + + /* + * Only mask cpu private IRQs here. + * "common" interrupts are masked at IDU, otherwise it would + * need to be unmasked at each cpu, with IPIs + */ + if (i < FIRST_EXT_IRQ) + write_aux_reg(AUX_IRQ_ENABLE, 0); + } + + /* setup status32, don't enable intr yet as kernel doesn't want */ + tmp = read_aux_reg(ARC_REG_STATUS32); + tmp |= ARCV2_IRQ_DEF_PRIO << 1; + tmp &= ~STATUS_IE_MASK; + asm volatile("kflag %0 \n"::"r"(tmp)); +} + +static void arcv2_irq_mask(struct irq_data *data) +{ + write_aux_reg(AUX_IRQ_SELECT, data->hwirq); + write_aux_reg(AUX_IRQ_ENABLE, 0); +} + +static void arcv2_irq_unmask(struct irq_data *data) +{ + write_aux_reg(AUX_IRQ_SELECT, data->hwirq); + write_aux_reg(AUX_IRQ_ENABLE, 1); +} + +void arcv2_irq_enable(struct irq_data *data) +{ + /* set default priority */ + write_aux_reg(AUX_IRQ_SELECT, data->hwirq); + write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO); + + /* + * hw auto enables (linux unmask) all by default + * So no need to do IRQ_ENABLE here + * XXX: However OSCI LAN need it + */ + write_aux_reg(AUX_IRQ_ENABLE, 1); +} + +static struct irq_chip arcv2_irq_chip = { + .name = "ARCv2 core Intc", + .irq_mask = arcv2_irq_mask, + .irq_unmask = arcv2_irq_unmask, + .irq_enable = arcv2_irq_enable +}; + +static int arcv2_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hw) +{ + /* + * core intc IRQs [16, 23]: + * Statically assigned always private-per-core (Timers, WDT, IPI, PCT) + */ + if (hw < FIRST_EXT_IRQ) { + /* + * A subsequent request_percpu_irq() fails if percpu_devid is + * not set. That in turns sets NOAUTOEN, meaning each core needs + * to call enable_percpu_irq() + */ + irq_set_percpu_devid(irq); + irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_percpu_irq); + } else { + irq_set_chip_and_handler(irq, &arcv2_irq_chip, handle_level_irq); + } + + return 0; +} + +static const struct irq_domain_ops arcv2_irq_ops = { + .xlate = irq_domain_xlate_onecell, + .map = arcv2_irq_map, +}; + + +static int __init +init_onchip_IRQ(struct device_node *intc, struct device_node *parent) +{ + struct irq_domain *root_domain; + struct bcr_irq_arcv2 irq_bcr; + unsigned int nr_cpu_irqs; + + READ_BCR(ARC_REG_IRQ_BCR, irq_bcr); + nr_cpu_irqs = irq_bcr.irqs + NR_EXCEPTIONS; + + if (parent) + panic("DeviceTree incore intc not a root irq controller\n"); + + root_domain = irq_domain_add_linear(intc, nr_cpu_irqs, &arcv2_irq_ops, NULL); + if (!root_domain) + panic("root irq domain not avail\n"); + + /* + * Needed for primary domain lookup to succeed + * This is a primary irqchip, and can never have a parent + */ + irq_set_default_host(root_domain); + +#ifdef CONFIG_SMP + irq_create_mapping(root_domain, IPI_IRQ); +#endif + irq_create_mapping(root_domain, SOFTIRQ_IRQ); + + return 0; +} + +IRQCHIP_DECLARE(arc_intc, "snps,archs-intc", init_onchip_IRQ); diff --git a/arch/arc/kernel/intc-compact.c b/arch/arc/kernel/intc-compact.c new file mode 100644 index 000000000..a86641b91 --- /dev/null +++ b/arch/arc/kernel/intc-compact.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/irqdomain.h> +#include <linux/irqchip.h> +#include <asm/irq.h> + +#define NR_CPU_IRQS 32 /* number of irq lines coming in */ +#define TIMER0_IRQ 3 /* Fixed by ISA */ + +/* + * Early Hardware specific Interrupt setup + * -Platform independent, needed for each CPU (not foldable into init_IRQ) + * -Called very early (start_kernel -> setup_arch -> setup_processor) + * + * what it does ? + * -Optionally, setup the High priority Interrupts as Level 2 IRQs + */ +void arc_init_IRQ(void) +{ + unsigned int level_mask = 0, i; + + /* Is timer high priority Interrupt (Level2 in ARCompact jargon) */ + level_mask |= IS_ENABLED(CONFIG_ARC_COMPACT_IRQ_LEVELS) << TIMER0_IRQ; + + /* + * Write to register, even if no LV2 IRQs configured to reset it + * in case bootloader had mucked with it + */ + write_aux_reg(AUX_IRQ_LEV, level_mask); + + if (level_mask) + pr_info("Level-2 interrupts bitset %x\n", level_mask); + + /* + * Disable all IRQ lines so faulty external hardware won't + * trigger interrupt that kernel is not ready to handle. + */ + for (i = TIMER0_IRQ; i < NR_CPU_IRQS; i++) { + unsigned int ienb; + + ienb = read_aux_reg(AUX_IENABLE); + ienb &= ~(1 << i); + write_aux_reg(AUX_IENABLE, ienb); + } +} + +/* + * ARC700 core includes a simple on-chip intc supporting + * -per IRQ enable/disable + * -2 levels of interrupts (high/low) + * -all interrupts being level triggered + * + * To reduce platform code, we assume all IRQs directly hooked-up into intc. + * Platforms with external intc, hence cascaded IRQs, are free to over-ride + * below, per IRQ. + */ + +static void arc_irq_mask(struct irq_data *data) +{ + unsigned int ienb; + + ienb = read_aux_reg(AUX_IENABLE); + ienb &= ~(1 << data->hwirq); + write_aux_reg(AUX_IENABLE, ienb); +} + +static void arc_irq_unmask(struct irq_data *data) +{ + unsigned int ienb; + + ienb = read_aux_reg(AUX_IENABLE); + ienb |= (1 << data->hwirq); + write_aux_reg(AUX_IENABLE, ienb); +} + +static struct irq_chip onchip_intc = { + .name = "ARC In-core Intc", + .irq_mask = arc_irq_mask, + .irq_unmask = arc_irq_unmask, +}; + +static int arc_intc_domain_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hw) +{ + switch (hw) { + case TIMER0_IRQ: + irq_set_percpu_devid(irq); + irq_set_chip_and_handler(irq, &onchip_intc, handle_percpu_irq); + break; + default: + irq_set_chip_and_handler(irq, &onchip_intc, handle_level_irq); + } + return 0; +} + +static const struct irq_domain_ops arc_intc_domain_ops = { + .xlate = irq_domain_xlate_onecell, + .map = arc_intc_domain_map, +}; + +static int __init +init_onchip_IRQ(struct device_node *intc, struct device_node *parent) +{ + struct irq_domain *root_domain; + + if (parent) + panic("DeviceTree incore intc not a root irq controller\n"); + + root_domain = irq_domain_add_linear(intc, NR_CPU_IRQS, + &arc_intc_domain_ops, NULL); + if (!root_domain) + panic("root irq domain not avail\n"); + + /* + * Needed for primary domain lookup to succeed + * This is a primary irqchip, and can never have a parent + */ + irq_set_default_host(root_domain); + + return 0; +} + +IRQCHIP_DECLARE(arc_intc, "snps,arc700-intc", init_onchip_IRQ); + +/* + * arch_local_irq_enable - Enable interrupts. + * + * 1. Explicitly called to re-enable interrupts + * 2. Implicitly called from spin_unlock_irq, write_unlock_irq etc + * which maybe in hard ISR itself + * + * Semantics of this function change depending on where it is called from: + * + * -If called from hard-ISR, it must not invert interrupt priorities + * e.g. suppose TIMER is high priority (Level 2) IRQ + * Time hard-ISR, timer_interrupt( ) calls spin_unlock_irq several times. + * Here local_irq_enable( ) shd not re-enable lower priority interrupts + * -If called from soft-ISR, it must re-enable all interrupts + * soft ISR are low prioity jobs which can be very slow, thus all IRQs + * must be enabled while they run. + * Now hardware context wise we may still be in L2 ISR (not done rtie) + * still we must re-enable both L1 and L2 IRQs + * Another twist is prev scenario with flow being + * L1 ISR ==> interrupted by L2 ISR ==> L2 soft ISR + * here we must not re-enable Ll as prev Ll Interrupt's h/w context will get + * over-written (this is deficiency in ARC700 Interrupt mechanism) + */ + +#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS /* Complex version for 2 IRQ levels */ + +void arch_local_irq_enable(void) +{ + unsigned long flags = arch_local_save_flags(); + + if (flags & STATUS_A2_MASK) + flags |= STATUS_E2_MASK; + else if (flags & STATUS_A1_MASK) + flags |= STATUS_E1_MASK; + + arch_local_irq_restore(flags); +} + +EXPORT_SYMBOL(arch_local_irq_enable); +#endif diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c new file mode 100644 index 000000000..ef909dd4b --- /dev/null +++ b/arch/arc/kernel/irq.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2011-12 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/interrupt.h> +#include <linux/irqchip.h> +#include <asm/mach_desc.h> +#include <asm/smp.h> + +/* + * Late Interrupt system init called from start_kernel for Boot CPU only + * + * Since slab must already be initialized, platforms can start doing any + * needed request_irq( )s + */ +void __init init_IRQ(void) +{ + /* + * process the entire interrupt tree in one go + * Any external intc will be setup provided DT chains them + * properly + */ + irqchip_init(); + +#ifdef CONFIG_SMP + /* a SMP H/w block could do IPI IRQ request here */ + if (plat_smp_ops.init_per_cpu) + plat_smp_ops.init_per_cpu(smp_processor_id()); +#endif + + if (machine_desc->init_per_cpu) + machine_desc->init_per_cpu(smp_processor_id()); +} + +/* + * "C" Entry point for any ARC ISR, called from low level vector handler + * @irq is the vector number read from ICAUSE reg of on-chip intc + */ +void arch_do_IRQ(unsigned int hwirq, struct pt_regs *regs) +{ + handle_domain_irq(NULL, hwirq, regs); +} diff --git a/arch/arc/kernel/jump_label.c b/arch/arc/kernel/jump_label.c new file mode 100644 index 000000000..b8600dc32 --- /dev/null +++ b/arch/arc/kernel/jump_label.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/kernel.h> +#include <linux/jump_label.h> + +#include "asm/cacheflush.h" + +#define JUMPLABEL_ERR "ARC: jump_label: ERROR: " + +/* Halt system on fatal error to make debug easier */ +#define arc_jl_fatal(format...) \ +({ \ + pr_err(JUMPLABEL_ERR format); \ + BUG(); \ +}) + +static inline u32 arc_gen_nop(void) +{ + /* 1x 32bit NOP in middle endian */ + return 0x7000264a; +} + +/* + * Atomic update of patched instruction is only available if this + * instruction doesn't cross L1 cache line boundary. You can read about + * the way we achieve this in arc/include/asm/jump_label.h + */ +static inline void instruction_align_assert(void *addr, int len) +{ + unsigned long a = (unsigned long)addr; + + if ((a >> L1_CACHE_SHIFT) != ((a + len - 1) >> L1_CACHE_SHIFT)) + arc_jl_fatal("instruction (addr %px) cross L1 cache line border", + addr); +} + +/* + * ARCv2 'Branch unconditionally' instruction: + * 00000ssssssssss1SSSSSSSSSSNRtttt + * s S[n:0] lower bits signed immediate (number is bitfield size) + * S S[m:n+1] upper bits signed immediate (number is bitfield size) + * t S[24:21] upper bits signed immediate (branch unconditionally far) + * N N <.d> delay slot mode + * R R Reserved + */ +static inline u32 arc_gen_branch(jump_label_t pc, jump_label_t target) +{ + u32 instruction_l, instruction_r; + u32 pcl = pc & GENMASK(31, 2); + u32 u_offset = target - pcl; + u32 s, S, t; + + /* + * Offset in 32-bit branch instruction must to fit into s25. + * Something is terribly broken if we get such huge offset within one + * function. + */ + if ((s32)u_offset < -16777216 || (s32)u_offset > 16777214) + arc_jl_fatal("gen branch with offset (%d) not fit in s25", + (s32)u_offset); + + /* + * All instructions are aligned by 2 bytes so we should never get offset + * here which is not 2 bytes aligned. + */ + if (u_offset & 0x1) + arc_jl_fatal("gen branch with offset (%d) unaligned to 2 bytes", + (s32)u_offset); + + s = (u_offset >> 1) & GENMASK(9, 0); + S = (u_offset >> 11) & GENMASK(9, 0); + t = (u_offset >> 21) & GENMASK(3, 0); + + /* 00000ssssssssss1 */ + instruction_l = (s << 1) | 0x1; + /* SSSSSSSSSSNRtttt */ + instruction_r = (S << 6) | t; + + return (instruction_r << 16) | (instruction_l & GENMASK(15, 0)); +} + +void arch_jump_label_transform(struct jump_entry *entry, + enum jump_label_type type) +{ + jump_label_t *instr_addr = (jump_label_t *)entry->code; + u32 instr; + + instruction_align_assert(instr_addr, JUMP_LABEL_NOP_SIZE); + + if (type == JUMP_LABEL_JMP) + instr = arc_gen_branch(entry->code, entry->target); + else + instr = arc_gen_nop(); + + WRITE_ONCE(*instr_addr, instr); + flush_icache_range(entry->code, entry->code + JUMP_LABEL_NOP_SIZE); +} + +void arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type) +{ + /* + * We use only one NOP type (1x, 4 byte) in arch_static_branch, so + * there's no need to patch an identical NOP over the top of it here. + * The generic code calls 'arch_jump_label_transform' if the NOP needs + * to be replaced by a branch, so 'arch_jump_label_transform_static' is + * never called with type other than JUMP_LABEL_NOP. + */ + BUG_ON(type != JUMP_LABEL_NOP); +} + +#ifdef CONFIG_ARC_DBG_JUMP_LABEL +#define SELFTEST_MSG "ARC: instruction generation self-test: " + +struct arc_gen_branch_testdata { + jump_label_t pc; + jump_label_t target_address; + u32 expected_instr; +}; + +static __init int branch_gen_test(const struct arc_gen_branch_testdata *test) +{ + u32 instr_got; + + instr_got = arc_gen_branch(test->pc, test->target_address); + if (instr_got == test->expected_instr) + return 0; + + pr_err(SELFTEST_MSG "FAIL:\n arc_gen_branch(0x%08x, 0x%08x) != 0x%08x, got 0x%08x\n", + test->pc, test->target_address, + test->expected_instr, instr_got); + + return -EFAULT; +} + +/* + * Offset field in branch instruction is not continuous. Test all + * available offset field and sign combinations. Test data is generated + * from real working code. + */ +static const struct arc_gen_branch_testdata arcgenbr_test_data[] __initconst = { + {0x90007548, 0x90007514, 0xffcf07cd}, /* tiny (-52) offs */ + {0x9000c9c0, 0x9000c782, 0xffcf05c3}, /* tiny (-574) offs */ + {0x9000cc1c, 0x9000c782, 0xffcf0367}, /* tiny (-1178) offs */ + {0x9009dce0, 0x9009d106, 0xff8f0427}, /* small (-3034) offs */ + {0x9000f5de, 0x90007d30, 0xfc0f0755}, /* big (-30892) offs */ + {0x900a2444, 0x90035f64, 0xc9cf0321}, /* huge (-443616) offs */ + {0x90007514, 0x9000752c, 0x00000019}, /* tiny (+24) offs */ + {0x9001a578, 0x9001a77a, 0x00000203}, /* tiny (+514) offs */ + {0x90031ed8, 0x90032634, 0x0000075d}, /* tiny (+1884) offs */ + {0x9008c7f2, 0x9008d3f0, 0x00400401}, /* small (+3072) offs */ + {0x9000bb38, 0x9003b340, 0x17c00009}, /* big (+194568) offs */ + {0x90008f44, 0x90578d80, 0xb7c2063d} /* huge (+5701180) offs */ +}; + +static __init int instr_gen_test(void) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(arcgenbr_test_data); i++) + if (branch_gen_test(&arcgenbr_test_data[i])) + return -EFAULT; + + pr_info(SELFTEST_MSG "OK\n"); + + return 0; +} +early_initcall(instr_gen_test); + +#endif /* CONFIG_ARC_DBG_JUMP_LABEL */ diff --git a/arch/arc/kernel/kgdb.c b/arch/arc/kernel/kgdb.c new file mode 100644 index 000000000..ecfbc42d3 --- /dev/null +++ b/arch/arc/kernel/kgdb.c @@ -0,0 +1,205 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * kgdb support for ARC + * + * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/kgdb.h> +#include <linux/sched.h> +#include <linux/sched/task_stack.h> +#include <asm/disasm.h> +#include <asm/cacheflush.h> + +static void to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs, + struct callee_regs *cregs) +{ + int regno; + + for (regno = 0; regno <= 26; regno++) + gdb_regs[_R0 + regno] = get_reg(regno, kernel_regs, cregs); + + for (regno = 27; regno < GDB_MAX_REGS; regno++) + gdb_regs[regno] = 0; + + gdb_regs[_FP] = kernel_regs->fp; + gdb_regs[__SP] = kernel_regs->sp; + gdb_regs[_BLINK] = kernel_regs->blink; + gdb_regs[_RET] = kernel_regs->ret; + gdb_regs[_STATUS32] = kernel_regs->status32; + gdb_regs[_LP_COUNT] = kernel_regs->lp_count; + gdb_regs[_LP_END] = kernel_regs->lp_end; + gdb_regs[_LP_START] = kernel_regs->lp_start; + gdb_regs[_BTA] = kernel_regs->bta; + gdb_regs[_STOP_PC] = kernel_regs->ret; +} + +static void from_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs, + struct callee_regs *cregs) +{ + int regno; + + for (regno = 0; regno <= 26; regno++) + set_reg(regno, gdb_regs[regno + _R0], kernel_regs, cregs); + + kernel_regs->fp = gdb_regs[_FP]; + kernel_regs->sp = gdb_regs[__SP]; + kernel_regs->blink = gdb_regs[_BLINK]; + kernel_regs->ret = gdb_regs[_RET]; + kernel_regs->status32 = gdb_regs[_STATUS32]; + kernel_regs->lp_count = gdb_regs[_LP_COUNT]; + kernel_regs->lp_end = gdb_regs[_LP_END]; + kernel_regs->lp_start = gdb_regs[_LP_START]; + kernel_regs->bta = gdb_regs[_BTA]; +} + + +void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs) +{ + to_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *) + current->thread.callee_reg); +} + +void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *kernel_regs) +{ + from_gdb_regs(gdb_regs, kernel_regs, (struct callee_regs *) + current->thread.callee_reg); +} + +void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, + struct task_struct *task) +{ + if (task) + to_gdb_regs(gdb_regs, task_pt_regs(task), + (struct callee_regs *) task->thread.callee_reg); +} + +struct single_step_data_t { + uint16_t opcode[2]; + unsigned long address[2]; + int is_branch; + int armed; +} single_step_data; + +static void undo_single_step(struct pt_regs *regs) +{ + if (single_step_data.armed) { + int i; + + for (i = 0; i < (single_step_data.is_branch ? 2 : 1); i++) { + memcpy((void *) single_step_data.address[i], + &single_step_data.opcode[i], + BREAK_INSTR_SIZE); + + flush_icache_range(single_step_data.address[i], + single_step_data.address[i] + + BREAK_INSTR_SIZE); + } + single_step_data.armed = 0; + } +} + +static void place_trap(unsigned long address, void *save) +{ + memcpy(save, (void *) address, BREAK_INSTR_SIZE); + memcpy((void *) address, &arch_kgdb_ops.gdb_bpt_instr, + BREAK_INSTR_SIZE); + flush_icache_range(address, address + BREAK_INSTR_SIZE); +} + +static void do_single_step(struct pt_regs *regs) +{ + single_step_data.is_branch = disasm_next_pc((unsigned long) + regs->ret, regs, (struct callee_regs *) + current->thread.callee_reg, + &single_step_data.address[0], + &single_step_data.address[1]); + + place_trap(single_step_data.address[0], &single_step_data.opcode[0]); + + if (single_step_data.is_branch) { + place_trap(single_step_data.address[1], + &single_step_data.opcode[1]); + } + + single_step_data.armed++; +} + +int kgdb_arch_handle_exception(int e_vector, int signo, int err_code, + char *remcomInBuffer, char *remcomOutBuffer, + struct pt_regs *regs) +{ + unsigned long addr; + char *ptr; + + undo_single_step(regs); + + switch (remcomInBuffer[0]) { + case 's': + case 'c': + ptr = &remcomInBuffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + regs->ret = addr; + + case 'D': + case 'k': + atomic_set(&kgdb_cpu_doing_single_step, -1); + + if (remcomInBuffer[0] == 's') { + do_single_step(regs); + atomic_set(&kgdb_cpu_doing_single_step, + smp_processor_id()); + } + + return 0; + } + return -1; +} + +int kgdb_arch_init(void) +{ + single_step_data.armed = 0; + return 0; +} + +void kgdb_trap(struct pt_regs *regs) +{ + /* trap_s 3 is used for breakpoints that overwrite existing + * instructions, while trap_s 4 is used for compiled breakpoints. + * + * with trap_s 3 breakpoints the original instruction needs to be + * restored and continuation needs to start at the location of the + * breakpoint. + * + * with trap_s 4 (compiled) breakpoints, continuation needs to + * start after the breakpoint. + */ + if (regs->ecr_param == 3) + instruction_pointer(regs) -= BREAK_INSTR_SIZE; + + kgdb_handle_exception(1, SIGTRAP, 0, regs); +} + +void kgdb_arch_exit(void) +{ +} + +void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long ip) +{ + instruction_pointer(regs) = ip; +} + +void kgdb_call_nmi_hook(void *ignored) +{ + /* Default implementation passes get_irq_regs() but we don't */ + kgdb_nmicallback(raw_smp_processor_id(), NULL); +} + +const struct kgdb_arch arch_kgdb_ops = { + /* breakpoint instruction: TRAP_S 0x3 */ +#ifdef CONFIG_CPU_BIG_ENDIAN + .gdb_bpt_instr = {0x78, 0x7e}, +#else + .gdb_bpt_instr = {0x7e, 0x78}, +#endif +}; diff --git a/arch/arc/kernel/kprobes.c b/arch/arc/kernel/kprobes.c new file mode 100644 index 000000000..cabef45f1 --- /dev/null +++ b/arch/arc/kernel/kprobes.c @@ -0,0 +1,430 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/types.h> +#include <linux/kprobes.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/kdebug.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <asm/cacheflush.h> +#include <asm/current.h> +#include <asm/disasm.h> + +#define MIN_STACK_SIZE(addr) min((unsigned long)MAX_STACK_SIZE, \ + (unsigned long)current_thread_info() + THREAD_SIZE - (addr)) + +DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL; +DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk); + +int __kprobes arch_prepare_kprobe(struct kprobe *p) +{ + /* Attempt to probe at unaligned address */ + if ((unsigned long)p->addr & 0x01) + return -EINVAL; + + /* Address should not be in exception handling code */ + + p->ainsn.is_short = is_short_instr((unsigned long)p->addr); + p->opcode = *p->addr; + + return 0; +} + +void __kprobes arch_arm_kprobe(struct kprobe *p) +{ + *p->addr = UNIMP_S_INSTRUCTION; + + flush_icache_range((unsigned long)p->addr, + (unsigned long)p->addr + sizeof(kprobe_opcode_t)); +} + +void __kprobes arch_disarm_kprobe(struct kprobe *p) +{ + *p->addr = p->opcode; + + flush_icache_range((unsigned long)p->addr, + (unsigned long)p->addr + sizeof(kprobe_opcode_t)); +} + +void __kprobes arch_remove_kprobe(struct kprobe *p) +{ + arch_disarm_kprobe(p); + + /* Can we remove the kprobe in the middle of kprobe handling? */ + if (p->ainsn.t1_addr) { + *(p->ainsn.t1_addr) = p->ainsn.t1_opcode; + + flush_icache_range((unsigned long)p->ainsn.t1_addr, + (unsigned long)p->ainsn.t1_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t1_addr = NULL; + } + + if (p->ainsn.t2_addr) { + *(p->ainsn.t2_addr) = p->ainsn.t2_opcode; + + flush_icache_range((unsigned long)p->ainsn.t2_addr, + (unsigned long)p->ainsn.t2_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t2_addr = NULL; + } +} + +static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb) +{ + kcb->prev_kprobe.kp = kprobe_running(); + kcb->prev_kprobe.status = kcb->kprobe_status; +} + +static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb) +{ + __this_cpu_write(current_kprobe, kcb->prev_kprobe.kp); + kcb->kprobe_status = kcb->prev_kprobe.status; +} + +static inline void __kprobes set_current_kprobe(struct kprobe *p) +{ + __this_cpu_write(current_kprobe, p); +} + +static void __kprobes resume_execution(struct kprobe *p, unsigned long addr, + struct pt_regs *regs) +{ + /* Remove the trap instructions inserted for single step and + * restore the original instructions + */ + if (p->ainsn.t1_addr) { + *(p->ainsn.t1_addr) = p->ainsn.t1_opcode; + + flush_icache_range((unsigned long)p->ainsn.t1_addr, + (unsigned long)p->ainsn.t1_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t1_addr = NULL; + } + + if (p->ainsn.t2_addr) { + *(p->ainsn.t2_addr) = p->ainsn.t2_opcode; + + flush_icache_range((unsigned long)p->ainsn.t2_addr, + (unsigned long)p->ainsn.t2_addr + + sizeof(kprobe_opcode_t)); + + p->ainsn.t2_addr = NULL; + } + + return; +} + +static void __kprobes setup_singlestep(struct kprobe *p, struct pt_regs *regs) +{ + unsigned long next_pc; + unsigned long tgt_if_br = 0; + int is_branch; + unsigned long bta; + + /* Copy the opcode back to the kprobe location and execute the + * instruction. Because of this we will not be able to get into the + * same kprobe until this kprobe is done + */ + *(p->addr) = p->opcode; + + flush_icache_range((unsigned long)p->addr, + (unsigned long)p->addr + sizeof(kprobe_opcode_t)); + + /* Now we insert the trap at the next location after this instruction to + * single step. If it is a branch we insert the trap at possible branch + * targets + */ + + bta = regs->bta; + + if (regs->status32 & 0x40) { + /* We are in a delay slot with the branch taken */ + + next_pc = bta & ~0x01; + + if (!p->ainsn.is_short) { + if (bta & 0x01) + regs->blink += 2; + else { + /* Branch not taken */ + next_pc += 2; + + /* next pc is taken from bta after executing the + * delay slot instruction + */ + regs->bta += 2; + } + } + + is_branch = 0; + } else + is_branch = + disasm_next_pc((unsigned long)p->addr, regs, + (struct callee_regs *) current->thread.callee_reg, + &next_pc, &tgt_if_br); + + p->ainsn.t1_addr = (kprobe_opcode_t *) next_pc; + p->ainsn.t1_opcode = *(p->ainsn.t1_addr); + *(p->ainsn.t1_addr) = TRAP_S_2_INSTRUCTION; + + flush_icache_range((unsigned long)p->ainsn.t1_addr, + (unsigned long)p->ainsn.t1_addr + + sizeof(kprobe_opcode_t)); + + if (is_branch) { + p->ainsn.t2_addr = (kprobe_opcode_t *) tgt_if_br; + p->ainsn.t2_opcode = *(p->ainsn.t2_addr); + *(p->ainsn.t2_addr) = TRAP_S_2_INSTRUCTION; + + flush_icache_range((unsigned long)p->ainsn.t2_addr, + (unsigned long)p->ainsn.t2_addr + + sizeof(kprobe_opcode_t)); + } +} + +int __kprobes arc_kprobe_handler(unsigned long addr, struct pt_regs *regs) +{ + struct kprobe *p; + struct kprobe_ctlblk *kcb; + + preempt_disable(); + + kcb = get_kprobe_ctlblk(); + p = get_kprobe((unsigned long *)addr); + + if (p) { + /* + * We have reentered the kprobe_handler, since another kprobe + * was hit while within the handler, we save the original + * kprobes and single step on the instruction of the new probe + * without calling any user handlers to avoid recursive + * kprobes. + */ + if (kprobe_running()) { + save_previous_kprobe(kcb); + set_current_kprobe(p); + kprobes_inc_nmissed_count(p); + setup_singlestep(p, regs); + kcb->kprobe_status = KPROBE_REENTER; + return 1; + } + + set_current_kprobe(p); + kcb->kprobe_status = KPROBE_HIT_ACTIVE; + + /* If we have no pre-handler or it returned 0, we continue with + * normal processing. If we have a pre-handler and it returned + * non-zero - which means user handler setup registers to exit + * to another instruction, we must skip the single stepping. + */ + if (!p->pre_handler || !p->pre_handler(p, regs)) { + setup_singlestep(p, regs); + kcb->kprobe_status = KPROBE_HIT_SS; + } else { + reset_current_kprobe(); + preempt_enable_no_resched(); + } + + return 1; + } + + /* no_kprobe: */ + preempt_enable_no_resched(); + return 0; +} + +static int __kprobes arc_post_kprobe_handler(unsigned long addr, + struct pt_regs *regs) +{ + struct kprobe *cur = kprobe_running(); + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + + if (!cur) + return 0; + + resume_execution(cur, addr, regs); + + /* Rearm the kprobe */ + arch_arm_kprobe(cur); + + /* + * When we return from trap instruction we go to the next instruction + * We restored the actual instruction in resume_exectuiont and we to + * return to the same address and execute it + */ + regs->ret = addr; + + if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) { + kcb->kprobe_status = KPROBE_HIT_SSDONE; + cur->post_handler(cur, regs, 0); + } + + if (kcb->kprobe_status == KPROBE_REENTER) { + restore_previous_kprobe(kcb); + goto out; + } + + reset_current_kprobe(); + +out: + preempt_enable_no_resched(); + return 1; +} + +/* + * Fault can be for the instruction being single stepped or for the + * pre/post handlers in the module. + * This is applicable for applications like user probes, where we have the + * probe in user space and the handlers in the kernel + */ + +int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned long trapnr) +{ + struct kprobe *cur = kprobe_running(); + struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); + + switch (kcb->kprobe_status) { + case KPROBE_HIT_SS: + case KPROBE_REENTER: + /* + * We are here because the instruction being single stepped + * caused the fault. We reset the current kprobe and allow the + * exception handler as if it is regular exception. In our + * case it doesn't matter because the system will be halted + */ + resume_execution(cur, (unsigned long)cur->addr, regs); + + if (kcb->kprobe_status == KPROBE_REENTER) + restore_previous_kprobe(kcb); + else + reset_current_kprobe(); + + preempt_enable_no_resched(); + break; + + case KPROBE_HIT_ACTIVE: + case KPROBE_HIT_SSDONE: + /* + * We are here because the instructions in the pre/post handler + * caused the fault. + */ + + /* We increment the nmissed count for accounting, + * we can also use npre/npostfault count for accounting + * these specific fault cases. + */ + kprobes_inc_nmissed_count(cur); + + /* + * We come here because instructions in the pre/post + * handler caused the page_fault, this could happen + * if handler tries to access user space by + * copy_from_user(), get_user() etc. Let the + * user-specified handler try to fix it first. + */ + if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr)) + return 1; + + /* + * In case the user-specified fault handler returned zero, + * try to fix up. + */ + if (fixup_exception(regs)) + return 1; + + /* + * fixup_exception() could not handle it, + * Let do_page_fault() fix it. + */ + break; + + default: + break; + } + return 0; +} + +int __kprobes kprobe_exceptions_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + struct die_args *args = data; + unsigned long addr = args->err; + int ret = NOTIFY_DONE; + + switch (val) { + case DIE_IERR: + if (arc_kprobe_handler(addr, args->regs)) + return NOTIFY_STOP; + break; + + case DIE_TRAP: + if (arc_post_kprobe_handler(addr, args->regs)) + return NOTIFY_STOP; + break; + + default: + break; + } + + return ret; +} + +static void __used kretprobe_trampoline_holder(void) +{ + __asm__ __volatile__(".global kretprobe_trampoline\n" + "kretprobe_trampoline:\n" "nop\n"); +} + +void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, + struct pt_regs *regs) +{ + + ri->ret_addr = (kprobe_opcode_t *) regs->blink; + ri->fp = NULL; + + /* Replace the return addr with trampoline addr */ + regs->blink = (unsigned long)&kretprobe_trampoline; +} + +static int __kprobes trampoline_probe_handler(struct kprobe *p, + struct pt_regs *regs) +{ + regs->ret = __kretprobe_trampoline_handler(regs, &kretprobe_trampoline, NULL); + + /* By returning a non zero value, we are telling the kprobe handler + * that we don't want the post_handler to run + */ + return 1; +} + +static struct kprobe trampoline_p = { + .addr = (kprobe_opcode_t *) &kretprobe_trampoline, + .pre_handler = trampoline_probe_handler +}; + +int __init arch_init_kprobes(void) +{ + /* Registering the trampoline code for the kret probe */ + return register_kprobe(&trampoline_p); +} + +int __kprobes arch_trampoline_kprobe(struct kprobe *p) +{ + if (p->addr == (kprobe_opcode_t *) &kretprobe_trampoline) + return 1; + + return 0; +} + +void trap_is_kprobe(unsigned long address, struct pt_regs *regs) +{ + notify_die(DIE_TRAP, "kprobe_trap", regs, address, 0, SIGTRAP); +} diff --git a/arch/arc/kernel/mcip.c b/arch/arc/kernel/mcip.c new file mode 100644 index 000000000..abf9398cc --- /dev/null +++ b/arch/arc/kernel/mcip.c @@ -0,0 +1,421 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ARC ARConnect (MultiCore IP) support (formerly known as MCIP) + * + * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/smp.h> +#include <linux/irq.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/spinlock.h> +#include <soc/arc/mcip.h> +#include <asm/irqflags-arcv2.h> +#include <asm/setup.h> + +static DEFINE_RAW_SPINLOCK(mcip_lock); + +#ifdef CONFIG_SMP + +static char smp_cpuinfo_buf[128]; + +/* + * Set mask to halt GFRC if any online core in SMP cluster is halted. + * Only works for ARC HS v3.0+, on earlier versions has no effect. + */ +static void mcip_update_gfrc_halt_mask(int cpu) +{ + struct bcr_generic gfrc; + unsigned long flags; + u32 gfrc_halt_mask; + + READ_BCR(ARC_REG_GFRC_BUILD, gfrc); + + /* + * CMD_GFRC_SET_CORE and CMD_GFRC_READ_CORE commands were added in + * GFRC 0x3 version. + */ + if (gfrc.ver < 0x3) + return; + + raw_spin_lock_irqsave(&mcip_lock, flags); + + __mcip_cmd(CMD_GFRC_READ_CORE, 0); + gfrc_halt_mask = read_aux_reg(ARC_REG_MCIP_READBACK); + gfrc_halt_mask |= BIT(cpu); + __mcip_cmd_data(CMD_GFRC_SET_CORE, 0, gfrc_halt_mask); + + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void mcip_update_debug_halt_mask(int cpu) +{ + u32 mcip_mask = 0; + unsigned long flags; + + raw_spin_lock_irqsave(&mcip_lock, flags); + + /* + * mcip_mask is same for CMD_DEBUG_SET_SELECT and CMD_DEBUG_SET_MASK + * commands. So read it once instead of reading both CMD_DEBUG_READ_MASK + * and CMD_DEBUG_READ_SELECT. + */ + __mcip_cmd(CMD_DEBUG_READ_SELECT, 0); + mcip_mask = read_aux_reg(ARC_REG_MCIP_READBACK); + + mcip_mask |= BIT(cpu); + + __mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, mcip_mask); + /* + * Parameter specified halt cause: + * STATUS32[H]/actionpoint/breakpoint/self-halt + * We choose all of them (0xF). + */ + __mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xF, mcip_mask); + + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void mcip_setup_per_cpu(int cpu) +{ + struct mcip_bcr mp; + + READ_BCR(ARC_REG_MCIP_BCR, mp); + + smp_ipi_irq_setup(cpu, IPI_IRQ); + smp_ipi_irq_setup(cpu, SOFTIRQ_IRQ); + + /* Update GFRC halt mask as new CPU came online */ + if (mp.gfrc) + mcip_update_gfrc_halt_mask(cpu); + + /* Update MCIP debug mask as new CPU came online */ + if (mp.dbg) + mcip_update_debug_halt_mask(cpu); +} + +static void mcip_ipi_send(int cpu) +{ + unsigned long flags; + int ipi_was_pending; + + /* ARConnect can only send IPI to others */ + if (unlikely(cpu == raw_smp_processor_id())) { + arc_softirq_trigger(SOFTIRQ_IRQ); + return; + } + + raw_spin_lock_irqsave(&mcip_lock, flags); + + /* + * If receiver already has a pending interrupt, elide sending this one. + * Linux cross core calling works well with concurrent IPIs + * coalesced into one + * see arch/arc/kernel/smp.c: ipi_send_msg_one() + */ + __mcip_cmd(CMD_INTRPT_READ_STATUS, cpu); + ipi_was_pending = read_aux_reg(ARC_REG_MCIP_READBACK); + if (!ipi_was_pending) + __mcip_cmd(CMD_INTRPT_GENERATE_IRQ, cpu); + + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void mcip_ipi_clear(int irq) +{ + unsigned int cpu, c; + unsigned long flags; + + if (unlikely(irq == SOFTIRQ_IRQ)) { + arc_softirq_clear(irq); + return; + } + + raw_spin_lock_irqsave(&mcip_lock, flags); + + /* Who sent the IPI */ + __mcip_cmd(CMD_INTRPT_CHECK_SOURCE, 0); + + cpu = read_aux_reg(ARC_REG_MCIP_READBACK); /* 1,2,4,8... */ + + /* + * In rare case, multiple concurrent IPIs sent to same target can + * possibly be coalesced by MCIP into 1 asserted IRQ, so @cpus can be + * "vectored" (multiple bits sets) as opposed to typical single bit + */ + do { + c = __ffs(cpu); /* 0,1,2,3 */ + __mcip_cmd(CMD_INTRPT_GENERATE_ACK, c); + cpu &= ~(1U << c); + } while (cpu); + + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void mcip_probe_n_setup(void) +{ + struct mcip_bcr mp; + + READ_BCR(ARC_REG_MCIP_BCR, mp); + + sprintf(smp_cpuinfo_buf, + "Extn [SMP]\t: ARConnect (v%d): %d cores with %s%s%s%s\n", + mp.ver, mp.num_cores, + IS_AVAIL1(mp.ipi, "IPI "), + IS_AVAIL1(mp.idu, "IDU "), + IS_AVAIL1(mp.dbg, "DEBUG "), + IS_AVAIL1(mp.gfrc, "GFRC")); + + cpuinfo_arc700[0].extn.gfrc = mp.gfrc; +} + +struct plat_smp_ops plat_smp_ops = { + .info = smp_cpuinfo_buf, + .init_early_smp = mcip_probe_n_setup, + .init_per_cpu = mcip_setup_per_cpu, + .ipi_send = mcip_ipi_send, + .ipi_clear = mcip_ipi_clear, +}; + +#endif + +/*************************************************************************** + * ARCv2 Interrupt Distribution Unit (IDU) + * + * Connects external "COMMON" IRQs to core intc, providing: + * -dynamic routing (IRQ affinity) + * -load balancing (Round Robin interrupt distribution) + * -1:N distribution + * + * It physically resides in the MCIP hw block + */ + +#include <linux/irqchip.h> +#include <linux/of.h> +#include <linux/of_irq.h> + +/* + * Set the DEST for @cmn_irq to @cpu_mask (1 bit per core) + */ +static void idu_set_dest(unsigned int cmn_irq, unsigned int cpu_mask) +{ + __mcip_cmd_data(CMD_IDU_SET_DEST, cmn_irq, cpu_mask); +} + +static void idu_set_mode(unsigned int cmn_irq, bool set_lvl, unsigned int lvl, + bool set_distr, unsigned int distr) +{ + union { + unsigned int word; + struct { + unsigned int distr:2, pad:2, lvl:1, pad2:27; + }; + } data; + + data.word = __mcip_cmd_read(CMD_IDU_READ_MODE, cmn_irq); + if (set_distr) + data.distr = distr; + if (set_lvl) + data.lvl = lvl; + __mcip_cmd_data(CMD_IDU_SET_MODE, cmn_irq, data.word); +} + +static void idu_irq_mask_raw(irq_hw_number_t hwirq) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&mcip_lock, flags); + __mcip_cmd_data(CMD_IDU_SET_MASK, hwirq, 1); + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void idu_irq_mask(struct irq_data *data) +{ + idu_irq_mask_raw(data->hwirq); +} + +static void idu_irq_unmask(struct irq_data *data) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&mcip_lock, flags); + __mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 0); + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void idu_irq_ack(struct irq_data *data) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&mcip_lock, flags); + __mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq); + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static void idu_irq_mask_ack(struct irq_data *data) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&mcip_lock, flags); + __mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 1); + __mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq); + raw_spin_unlock_irqrestore(&mcip_lock, flags); +} + +static int +idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask, + bool force) +{ + unsigned long flags; + cpumask_t online; + unsigned int destination_bits; + unsigned int distribution_mode; + + /* errout if no online cpu per @cpumask */ + if (!cpumask_and(&online, cpumask, cpu_online_mask)) + return -EINVAL; + + raw_spin_lock_irqsave(&mcip_lock, flags); + + destination_bits = cpumask_bits(&online)[0]; + idu_set_dest(data->hwirq, destination_bits); + + if (ffs(destination_bits) == fls(destination_bits)) + distribution_mode = IDU_M_DISTRI_DEST; + else + distribution_mode = IDU_M_DISTRI_RR; + + idu_set_mode(data->hwirq, false, 0, true, distribution_mode); + + raw_spin_unlock_irqrestore(&mcip_lock, flags); + + return IRQ_SET_MASK_OK; +} + +static int idu_irq_set_type(struct irq_data *data, u32 type) +{ + unsigned long flags; + + /* + * ARCv2 IDU HW does not support inverse polarity, so these are the + * only interrupt types supported. + */ + if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH)) + return -EINVAL; + + raw_spin_lock_irqsave(&mcip_lock, flags); + + idu_set_mode(data->hwirq, true, + type & IRQ_TYPE_EDGE_RISING ? IDU_M_TRIG_EDGE : + IDU_M_TRIG_LEVEL, + false, 0); + + raw_spin_unlock_irqrestore(&mcip_lock, flags); + + return 0; +} + +static void idu_irq_enable(struct irq_data *data) +{ + /* + * By default send all common interrupts to all available online CPUs. + * The affinity of common interrupts in IDU must be set manually since + * in some cases the kernel will not call irq_set_affinity() by itself: + * 1. When the kernel is not configured with support of SMP. + * 2. When the kernel is configured with support of SMP but upper + * interrupt controllers does not support setting of the affinity + * and cannot propagate it to IDU. + */ + idu_irq_set_affinity(data, cpu_online_mask, false); + idu_irq_unmask(data); +} + +static struct irq_chip idu_irq_chip = { + .name = "MCIP IDU Intc", + .irq_mask = idu_irq_mask, + .irq_unmask = idu_irq_unmask, + .irq_ack = idu_irq_ack, + .irq_mask_ack = idu_irq_mask_ack, + .irq_enable = idu_irq_enable, + .irq_set_type = idu_irq_set_type, +#ifdef CONFIG_SMP + .irq_set_affinity = idu_irq_set_affinity, +#endif + +}; + +static void idu_cascade_isr(struct irq_desc *desc) +{ + struct irq_domain *idu_domain = irq_desc_get_handler_data(desc); + struct irq_chip *core_chip = irq_desc_get_chip(desc); + irq_hw_number_t core_hwirq = irqd_to_hwirq(irq_desc_get_irq_data(desc)); + irq_hw_number_t idu_hwirq = core_hwirq - FIRST_EXT_IRQ; + + chained_irq_enter(core_chip, desc); + generic_handle_irq(irq_find_mapping(idu_domain, idu_hwirq)); + chained_irq_exit(core_chip, desc); +} + +static int idu_irq_map(struct irq_domain *d, unsigned int virq, irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(virq, &idu_irq_chip, handle_level_irq); + irq_set_status_flags(virq, IRQ_MOVE_PCNTXT); + + return 0; +} + +static const struct irq_domain_ops idu_irq_ops = { + .xlate = irq_domain_xlate_onetwocell, + .map = idu_irq_map, +}; + +/* + * [16, 23]: Statically assigned always private-per-core (Timers, WDT, IPI) + * [24, 23+C]: If C > 0 then "C" common IRQs + * [24+C, N]: Not statically assigned, private-per-core + */ + + +static int __init +idu_of_init(struct device_node *intc, struct device_node *parent) +{ + struct irq_domain *domain; + int nr_irqs; + int i, virq; + struct mcip_bcr mp; + struct mcip_idu_bcr idu_bcr; + + READ_BCR(ARC_REG_MCIP_BCR, mp); + + if (!mp.idu) + panic("IDU not detected, but DeviceTree using it"); + + READ_BCR(ARC_REG_MCIP_IDU_BCR, idu_bcr); + nr_irqs = mcip_idu_bcr_to_nr_irqs(idu_bcr); + + pr_info("MCIP: IDU supports %u common irqs\n", nr_irqs); + + domain = irq_domain_add_linear(intc, nr_irqs, &idu_irq_ops, NULL); + + /* Parent interrupts (core-intc) are already mapped */ + + for (i = 0; i < nr_irqs; i++) { + /* Mask all common interrupts by default */ + idu_irq_mask_raw(i); + + /* + * Return parent uplink IRQs (towards core intc) 24,25,..... + * this step has been done before already + * however we need it to get the parent virq and set IDU handler + * as first level isr + */ + virq = irq_create_mapping(NULL, i + FIRST_EXT_IRQ); + BUG_ON(!virq); + irq_set_chained_handler_and_data(virq, idu_cascade_isr, domain); + } + + __mcip_cmd(CMD_IDU_ENABLE, 0); + + return 0; +} +IRQCHIP_DECLARE(arcv2_idu_intc, "snps,archs-idu-intc", idu_of_init); diff --git a/arch/arc/kernel/module.c b/arch/arc/kernel/module.c new file mode 100644 index 000000000..c90c27904 --- /dev/null +++ b/arch/arc/kernel/module.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/module.h> +#include <linux/moduleloader.h> +#include <linux/kernel.h> +#include <linux/elf.h> +#include <linux/vmalloc.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/string.h> +#include <asm/unwind.h> + +static inline void arc_write_me(unsigned short *addr, unsigned long value) +{ + *addr = (value & 0xffff0000) >> 16; + *(addr + 1) = (value & 0xffff); +} + +/* + * This gets called before relocation loop in generic loader + * Make a note of the section index of unwinding section + */ +int module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, + char *secstr, struct module *mod) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + mod->arch.unw_sec_idx = 0; + mod->arch.unw_info = NULL; +#endif + mod->arch.secstr = secstr; + return 0; +} + +void module_arch_cleanup(struct module *mod) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + if (mod->arch.unw_info) + unwind_remove_table(mod->arch.unw_info, 0); +#endif +} + +int apply_relocate_add(Elf32_Shdr *sechdrs, + const char *strtab, + unsigned int symindex, /* sec index for sym tbl */ + unsigned int relsec, /* sec index for relo sec */ + struct module *module) +{ + int i, n, relo_type; + Elf32_Rela *rel_entry = (void *)sechdrs[relsec].sh_addr; + Elf32_Sym *sym_entry, *sym_sec; + Elf32_Addr relocation, location, tgt_addr; + unsigned int tgtsec; + + /* + * @relsec has relocations e.g. .rela.init.text + * @tgtsec is section to patch e.g. .init.text + */ + tgtsec = sechdrs[relsec].sh_info; + tgt_addr = sechdrs[tgtsec].sh_addr; + sym_sec = (Elf32_Sym *) sechdrs[symindex].sh_addr; + n = sechdrs[relsec].sh_size / sizeof(*rel_entry); + + pr_debug("\nSection to fixup %s @%x\n", + module->arch.secstr + sechdrs[tgtsec].sh_name, tgt_addr); + pr_debug("=========================================================\n"); + pr_debug("r_off\tr_add\tst_value ADDRESS VALUE\n"); + pr_debug("=========================================================\n"); + + /* Loop thru entries in relocation section */ + for (i = 0; i < n; i++) { + const char *s; + + /* This is where to make the change */ + location = tgt_addr + rel_entry[i].r_offset; + + /* This is the symbol it is referring to. Note that all + undefined symbols have been resolved. */ + sym_entry = sym_sec + ELF32_R_SYM(rel_entry[i].r_info); + + relocation = sym_entry->st_value + rel_entry[i].r_addend; + + if (sym_entry->st_name == 0 && ELF_ST_TYPE (sym_entry->st_info) == STT_SECTION) { + s = module->arch.secstr + sechdrs[sym_entry->st_shndx].sh_name; + } else { + s = strtab + sym_entry->st_name; + } + + pr_debug(" %x\t%x\t%x %x %x [%s]\n", + rel_entry[i].r_offset, rel_entry[i].r_addend, + sym_entry->st_value, location, relocation, s); + + /* This assumes modules are built with -mlong-calls + * so any branches/jumps are absolute 32 bit jmps + * global data access again is abs 32 bit. + * Both of these are handled by same relocation type + */ + relo_type = ELF32_R_TYPE(rel_entry[i].r_info); + + if (likely(R_ARC_32_ME == relo_type)) /* ME ( S + A ) */ + arc_write_me((unsigned short *)location, relocation); + else if (R_ARC_32 == relo_type) /* ( S + A ) */ + *((Elf32_Addr *) location) = relocation; + else if (R_ARC_32_PCREL == relo_type) /* ( S + A ) - PDATA ) */ + *((Elf32_Addr *) location) = relocation - location; + else + goto relo_err; + + } + +#ifdef CONFIG_ARC_DW2_UNWIND + if (strcmp(module->arch.secstr+sechdrs[tgtsec].sh_name, ".eh_frame") == 0) + module->arch.unw_sec_idx = tgtsec; +#endif + + return 0; + +relo_err: + pr_err("%s: unknown relocation: %u\n", + module->name, ELF32_R_TYPE(rel_entry[i].r_info)); + return -ENOEXEC; + +} + +/* Just before lift off: After sections have been relocated, we add the + * dwarf section to unwinder table pool + * This couldn't be done in module_frob_arch_sections() because + * relocations had not been applied by then + */ +int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs, + struct module *mod) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + void *unw; + int unwsec = mod->arch.unw_sec_idx; + + if (unwsec) { + unw = unwind_add_table(mod, (void *)sechdrs[unwsec].sh_addr, + sechdrs[unwsec].sh_size); + mod->arch.unw_info = unw; + } +#endif + return 0; +} diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c new file mode 100644 index 000000000..145722f80 --- /dev/null +++ b/arch/arc/kernel/perf_event.c @@ -0,0 +1,688 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Linux performance counter support for ARC CPUs. +// This code is inspired by the perf support of various other architectures. +// +// Copyright (C) 2013-2018 Synopsys, Inc. (www.synopsys.com) + +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/perf_event.h> +#include <linux/platform_device.h> +#include <asm/arcregs.h> +#include <asm/stacktrace.h> + +/* HW holds 8 symbols + one for null terminator */ +#define ARCPMU_EVENT_NAME_LEN 9 + +enum arc_pmu_attr_groups { + ARCPMU_ATTR_GR_EVENTS, + ARCPMU_ATTR_GR_FORMATS, + ARCPMU_NR_ATTR_GR +}; + +struct arc_pmu_raw_event_entry { + char name[ARCPMU_EVENT_NAME_LEN]; +}; + +struct arc_pmu { + struct pmu pmu; + unsigned int irq; + int n_counters; + int n_events; + u64 max_period; + int ev_hw_idx[PERF_COUNT_ARC_HW_MAX]; + + struct arc_pmu_raw_event_entry *raw_entry; + struct attribute **attrs; + struct perf_pmu_events_attr *attr; + const struct attribute_group *attr_groups[ARCPMU_NR_ATTR_GR + 1]; +}; + +struct arc_pmu_cpu { + /* + * A 1 bit for an index indicates that the counter is being used for + * an event. A 0 means that the counter can be used. + */ + unsigned long used_mask[BITS_TO_LONGS(ARC_PERF_MAX_COUNTERS)]; + + /* + * The events that are active on the PMU for the given index. + */ + struct perf_event *act_counter[ARC_PERF_MAX_COUNTERS]; +}; + +struct arc_callchain_trace { + int depth; + void *perf_stuff; +}; + +static int callchain_trace(unsigned int addr, void *data) +{ + struct arc_callchain_trace *ctrl = data; + struct perf_callchain_entry_ctx *entry = ctrl->perf_stuff; + + perf_callchain_store(entry, addr); + + if (ctrl->depth++ < 3) + return 0; + + return -1; +} + +void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, + struct pt_regs *regs) +{ + struct arc_callchain_trace ctrl = { + .depth = 0, + .perf_stuff = entry, + }; + + arc_unwind_core(NULL, regs, callchain_trace, &ctrl); +} + +void perf_callchain_user(struct perf_callchain_entry_ctx *entry, + struct pt_regs *regs) +{ + /* + * User stack can't be unwound trivially with kernel dwarf unwinder + * So for now just record the user PC + */ + perf_callchain_store(entry, instruction_pointer(regs)); +} + +static struct arc_pmu *arc_pmu; +static DEFINE_PER_CPU(struct arc_pmu_cpu, arc_pmu_cpu); + +/* read counter #idx; note that counter# != event# on ARC! */ +static u64 arc_pmu_read_counter(int idx) +{ + u32 tmp; + u64 result; + + /* + * ARC supports making 'snapshots' of the counters, so we don't + * need to care about counters wrapping to 0 underneath our feet + */ + write_aux_reg(ARC_REG_PCT_INDEX, idx); + tmp = read_aux_reg(ARC_REG_PCT_CONTROL); + write_aux_reg(ARC_REG_PCT_CONTROL, tmp | ARC_REG_PCT_CONTROL_SN); + result = (u64) (read_aux_reg(ARC_REG_PCT_SNAPH)) << 32; + result |= read_aux_reg(ARC_REG_PCT_SNAPL); + + return result; +} + +static void arc_perf_event_update(struct perf_event *event, + struct hw_perf_event *hwc, int idx) +{ + u64 prev_raw_count = local64_read(&hwc->prev_count); + u64 new_raw_count = arc_pmu_read_counter(idx); + s64 delta = new_raw_count - prev_raw_count; + + /* + * We aren't afraid of hwc->prev_count changing beneath our feet + * because there's no way for us to re-enter this function anytime. + */ + local64_set(&hwc->prev_count, new_raw_count); + local64_add(delta, &event->count); + local64_sub(delta, &hwc->period_left); +} + +static void arc_pmu_read(struct perf_event *event) +{ + arc_perf_event_update(event, &event->hw, event->hw.idx); +} + +static int arc_pmu_cache_event(u64 config) +{ + unsigned int cache_type, cache_op, cache_result; + int ret; + + cache_type = (config >> 0) & 0xff; + cache_op = (config >> 8) & 0xff; + cache_result = (config >> 16) & 0xff; + if (cache_type >= PERF_COUNT_HW_CACHE_MAX) + return -EINVAL; + if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX) + return -EINVAL; + if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX) + return -EINVAL; + + ret = arc_pmu_cache_map[cache_type][cache_op][cache_result]; + + if (ret == CACHE_OP_UNSUPPORTED) + return -ENOENT; + + pr_debug("init cache event: type/op/result %d/%d/%d with h/w %d \'%s\'\n", + cache_type, cache_op, cache_result, ret, + arc_pmu_ev_hw_map[ret]); + + return ret; +} + +/* initializes hw_perf_event structure if event is supported */ +static int arc_pmu_event_init(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + int ret; + + if (!is_sampling_event(event)) { + hwc->sample_period = arc_pmu->max_period; + hwc->last_period = hwc->sample_period; + local64_set(&hwc->period_left, hwc->sample_period); + } + + hwc->config = 0; + + if (is_isa_arcv2()) { + /* "exclude user" means "count only kernel" */ + if (event->attr.exclude_user) + hwc->config |= ARC_REG_PCT_CONFIG_KERN; + + /* "exclude kernel" means "count only user" */ + if (event->attr.exclude_kernel) + hwc->config |= ARC_REG_PCT_CONFIG_USER; + } + + switch (event->attr.type) { + case PERF_TYPE_HARDWARE: + if (event->attr.config >= PERF_COUNT_HW_MAX) + return -ENOENT; + if (arc_pmu->ev_hw_idx[event->attr.config] < 0) + return -ENOENT; + hwc->config |= arc_pmu->ev_hw_idx[event->attr.config]; + pr_debug("init event %d with h/w %08x \'%s\'\n", + (int)event->attr.config, (int)hwc->config, + arc_pmu_ev_hw_map[event->attr.config]); + return 0; + + case PERF_TYPE_HW_CACHE: + ret = arc_pmu_cache_event(event->attr.config); + if (ret < 0) + return ret; + hwc->config |= arc_pmu->ev_hw_idx[ret]; + pr_debug("init cache event with h/w %08x \'%s\'\n", + (int)hwc->config, arc_pmu_ev_hw_map[ret]); + return 0; + + case PERF_TYPE_RAW: + if (event->attr.config >= arc_pmu->n_events) + return -ENOENT; + + hwc->config |= event->attr.config; + pr_debug("init raw event with idx %lld \'%s\'\n", + event->attr.config, + arc_pmu->raw_entry[event->attr.config].name); + + return 0; + + default: + return -ENOENT; + } +} + +/* starts all counters */ +static void arc_pmu_enable(struct pmu *pmu) +{ + u32 tmp; + tmp = read_aux_reg(ARC_REG_PCT_CONTROL); + write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x1); +} + +/* stops all counters */ +static void arc_pmu_disable(struct pmu *pmu) +{ + u32 tmp; + tmp = read_aux_reg(ARC_REG_PCT_CONTROL); + write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x0); +} + +static int arc_pmu_event_set_period(struct perf_event *event) +{ + struct hw_perf_event *hwc = &event->hw; + s64 left = local64_read(&hwc->period_left); + s64 period = hwc->sample_period; + int idx = hwc->idx; + int overflow = 0; + u64 value; + + if (unlikely(left <= -period)) { + /* left underflowed by more than period. */ + left = period; + local64_set(&hwc->period_left, left); + hwc->last_period = period; + overflow = 1; + } else if (unlikely(left <= 0)) { + /* left underflowed by less than period. */ + left += period; + local64_set(&hwc->period_left, left); + hwc->last_period = period; + overflow = 1; + } + + if (left > arc_pmu->max_period) + left = arc_pmu->max_period; + + value = arc_pmu->max_period - left; + local64_set(&hwc->prev_count, value); + + /* Select counter */ + write_aux_reg(ARC_REG_PCT_INDEX, idx); + + /* Write value */ + write_aux_reg(ARC_REG_PCT_COUNTL, lower_32_bits(value)); + write_aux_reg(ARC_REG_PCT_COUNTH, upper_32_bits(value)); + + perf_event_update_userpage(event); + + return overflow; +} + +/* + * Assigns hardware counter to hardware condition. + * Note that there is no separate start/stop mechanism; + * stopping is achieved by assigning the 'never' condition + */ +static void arc_pmu_start(struct perf_event *event, int flags) +{ + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + if (WARN_ON_ONCE(idx == -1)) + return; + + if (flags & PERF_EF_RELOAD) + WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE)); + + hwc->state = 0; + + arc_pmu_event_set_period(event); + + /* Enable interrupt for this counter */ + if (is_sampling_event(event)) + write_aux_reg(ARC_REG_PCT_INT_CTRL, + read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx)); + + /* enable ARC pmu here */ + write_aux_reg(ARC_REG_PCT_INDEX, idx); /* counter # */ + write_aux_reg(ARC_REG_PCT_CONFIG, hwc->config); /* condition */ +} + +static void arc_pmu_stop(struct perf_event *event, int flags) +{ + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + /* Disable interrupt for this counter */ + if (is_sampling_event(event)) { + /* + * Reset interrupt flag by writing of 1. This is required + * to make sure pending interrupt was not left. + */ + write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx)); + write_aux_reg(ARC_REG_PCT_INT_CTRL, + read_aux_reg(ARC_REG_PCT_INT_CTRL) & ~BIT(idx)); + } + + if (!(event->hw.state & PERF_HES_STOPPED)) { + /* stop ARC pmu here */ + write_aux_reg(ARC_REG_PCT_INDEX, idx); + + /* condition code #0 is always "never" */ + write_aux_reg(ARC_REG_PCT_CONFIG, 0); + + event->hw.state |= PERF_HES_STOPPED; + } + + if ((flags & PERF_EF_UPDATE) && + !(event->hw.state & PERF_HES_UPTODATE)) { + arc_perf_event_update(event, &event->hw, idx); + event->hw.state |= PERF_HES_UPTODATE; + } +} + +static void arc_pmu_del(struct perf_event *event, int flags) +{ + struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu); + + arc_pmu_stop(event, PERF_EF_UPDATE); + __clear_bit(event->hw.idx, pmu_cpu->used_mask); + + pmu_cpu->act_counter[event->hw.idx] = 0; + + perf_event_update_userpage(event); +} + +/* allocate hardware counter and optionally start counting */ +static int arc_pmu_add(struct perf_event *event, int flags) +{ + struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu); + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + idx = ffz(pmu_cpu->used_mask[0]); + if (idx == arc_pmu->n_counters) + return -EAGAIN; + + __set_bit(idx, pmu_cpu->used_mask); + hwc->idx = idx; + + write_aux_reg(ARC_REG_PCT_INDEX, idx); + + pmu_cpu->act_counter[idx] = event; + + if (is_sampling_event(event)) { + /* Mimic full counter overflow as other arches do */ + write_aux_reg(ARC_REG_PCT_INT_CNTL, + lower_32_bits(arc_pmu->max_period)); + write_aux_reg(ARC_REG_PCT_INT_CNTH, + upper_32_bits(arc_pmu->max_period)); + } + + write_aux_reg(ARC_REG_PCT_CONFIG, 0); + write_aux_reg(ARC_REG_PCT_COUNTL, 0); + write_aux_reg(ARC_REG_PCT_COUNTH, 0); + local64_set(&hwc->prev_count, 0); + + hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED; + if (flags & PERF_EF_START) + arc_pmu_start(event, PERF_EF_RELOAD); + + perf_event_update_userpage(event); + + return 0; +} + +#ifdef CONFIG_ISA_ARCV2 +static irqreturn_t arc_pmu_intr(int irq, void *dev) +{ + struct perf_sample_data data; + struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu); + struct pt_regs *regs; + unsigned int active_ints; + int idx; + + arc_pmu_disable(&arc_pmu->pmu); + + active_ints = read_aux_reg(ARC_REG_PCT_INT_ACT); + if (!active_ints) + goto done; + + regs = get_irq_regs(); + + do { + struct perf_event *event; + struct hw_perf_event *hwc; + + idx = __ffs(active_ints); + + /* Reset interrupt flag by writing of 1 */ + write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx)); + + /* + * On reset of "interrupt active" bit corresponding + * "interrupt enable" bit gets automatically reset as well. + * Now we need to re-enable interrupt for the counter. + */ + write_aux_reg(ARC_REG_PCT_INT_CTRL, + read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx)); + + event = pmu_cpu->act_counter[idx]; + hwc = &event->hw; + + WARN_ON_ONCE(hwc->idx != idx); + + arc_perf_event_update(event, &event->hw, event->hw.idx); + perf_sample_data_init(&data, 0, hwc->last_period); + if (arc_pmu_event_set_period(event)) { + if (perf_event_overflow(event, &data, regs)) + arc_pmu_stop(event, 0); + } + + active_ints &= ~BIT(idx); + } while (active_ints); + +done: + arc_pmu_enable(&arc_pmu->pmu); + + return IRQ_HANDLED; +} +#else + +static irqreturn_t arc_pmu_intr(int irq, void *dev) +{ + return IRQ_NONE; +} + +#endif /* CONFIG_ISA_ARCV2 */ + +static void arc_cpu_pmu_irq_init(void *data) +{ + int irq = *(int *)data; + + enable_percpu_irq(irq, IRQ_TYPE_NONE); + + /* Clear all pending interrupt flags */ + write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff); +} + +/* Event field occupies the bottom 15 bits of our config field */ +PMU_FORMAT_ATTR(event, "config:0-14"); +static struct attribute *arc_pmu_format_attrs[] = { + &format_attr_event.attr, + NULL, +}; + +static struct attribute_group arc_pmu_format_attr_gr = { + .name = "format", + .attrs = arc_pmu_format_attrs, +}; + +static ssize_t arc_pmu_events_sysfs_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct perf_pmu_events_attr *pmu_attr; + + pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); + return sprintf(page, "event=0x%04llx\n", pmu_attr->id); +} + +/* + * We don't add attrs here as we don't have pre-defined list of perf events. + * We will generate and add attrs dynamically in probe() after we read HW + * configuration. + */ +static struct attribute_group arc_pmu_events_attr_gr = { + .name = "events", +}; + +static void arc_pmu_add_raw_event_attr(int j, char *str) +{ + memmove(arc_pmu->raw_entry[j].name, str, ARCPMU_EVENT_NAME_LEN - 1); + arc_pmu->attr[j].attr.attr.name = arc_pmu->raw_entry[j].name; + arc_pmu->attr[j].attr.attr.mode = VERIFY_OCTAL_PERMISSIONS(0444); + arc_pmu->attr[j].attr.show = arc_pmu_events_sysfs_show; + arc_pmu->attr[j].id = j; + arc_pmu->attrs[j] = &(arc_pmu->attr[j].attr.attr); +} + +static int arc_pmu_raw_alloc(struct device *dev) +{ + arc_pmu->attr = devm_kmalloc_array(dev, arc_pmu->n_events + 1, + sizeof(*arc_pmu->attr), GFP_KERNEL | __GFP_ZERO); + if (!arc_pmu->attr) + return -ENOMEM; + + arc_pmu->attrs = devm_kmalloc_array(dev, arc_pmu->n_events + 1, + sizeof(*arc_pmu->attrs), GFP_KERNEL | __GFP_ZERO); + if (!arc_pmu->attrs) + return -ENOMEM; + + arc_pmu->raw_entry = devm_kmalloc_array(dev, arc_pmu->n_events, + sizeof(*arc_pmu->raw_entry), GFP_KERNEL | __GFP_ZERO); + if (!arc_pmu->raw_entry) + return -ENOMEM; + + return 0; +} + +static inline bool event_in_hw_event_map(int i, char *name) +{ + if (!arc_pmu_ev_hw_map[i]) + return false; + + if (!strlen(arc_pmu_ev_hw_map[i])) + return false; + + if (strcmp(arc_pmu_ev_hw_map[i], name)) + return false; + + return true; +} + +static void arc_pmu_map_hw_event(int j, char *str) +{ + int i; + + /* See if HW condition has been mapped to a perf event_id */ + for (i = 0; i < ARRAY_SIZE(arc_pmu_ev_hw_map); i++) { + if (event_in_hw_event_map(i, str)) { + pr_debug("mapping perf event %2d to h/w event \'%8s\' (idx %d)\n", + i, str, j); + arc_pmu->ev_hw_idx[i] = j; + } + } +} + +static int arc_pmu_device_probe(struct platform_device *pdev) +{ + struct arc_reg_pct_build pct_bcr; + struct arc_reg_cc_build cc_bcr; + int i, has_interrupts, irq = -1; + int counter_size; /* in bits */ + + union cc_name { + struct { + u32 word0, word1; + char sentinel; + } indiv; + char str[ARCPMU_EVENT_NAME_LEN]; + } cc_name; + + + READ_BCR(ARC_REG_PCT_BUILD, pct_bcr); + if (!pct_bcr.v) { + pr_err("This core does not have performance counters!\n"); + return -ENODEV; + } + BUILD_BUG_ON(ARC_PERF_MAX_COUNTERS > 32); + if (WARN_ON(pct_bcr.c > ARC_PERF_MAX_COUNTERS)) + return -EINVAL; + + READ_BCR(ARC_REG_CC_BUILD, cc_bcr); + if (WARN(!cc_bcr.v, "Counters exist but No countable conditions?")) + return -EINVAL; + + arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu), GFP_KERNEL); + if (!arc_pmu) + return -ENOMEM; + + arc_pmu->n_events = cc_bcr.c; + + if (arc_pmu_raw_alloc(&pdev->dev)) + return -ENOMEM; + + has_interrupts = is_isa_arcv2() ? pct_bcr.i : 0; + + arc_pmu->n_counters = pct_bcr.c; + counter_size = 32 + (pct_bcr.s << 4); + + arc_pmu->max_period = (1ULL << counter_size) / 2 - 1ULL; + + pr_info("ARC perf\t: %d counters (%d bits), %d conditions%s\n", + arc_pmu->n_counters, counter_size, cc_bcr.c, + has_interrupts ? ", [overflow IRQ support]" : ""); + + cc_name.str[ARCPMU_EVENT_NAME_LEN - 1] = 0; + for (i = 0; i < PERF_COUNT_ARC_HW_MAX; i++) + arc_pmu->ev_hw_idx[i] = -1; + + /* loop thru all available h/w condition indexes */ + for (i = 0; i < cc_bcr.c; i++) { + write_aux_reg(ARC_REG_CC_INDEX, i); + cc_name.indiv.word0 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME0)); + cc_name.indiv.word1 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME1)); + + arc_pmu_map_hw_event(i, cc_name.str); + arc_pmu_add_raw_event_attr(i, cc_name.str); + } + + arc_pmu_events_attr_gr.attrs = arc_pmu->attrs; + arc_pmu->attr_groups[ARCPMU_ATTR_GR_EVENTS] = &arc_pmu_events_attr_gr; + arc_pmu->attr_groups[ARCPMU_ATTR_GR_FORMATS] = &arc_pmu_format_attr_gr; + + arc_pmu->pmu = (struct pmu) { + .pmu_enable = arc_pmu_enable, + .pmu_disable = arc_pmu_disable, + .event_init = arc_pmu_event_init, + .add = arc_pmu_add, + .del = arc_pmu_del, + .start = arc_pmu_start, + .stop = arc_pmu_stop, + .read = arc_pmu_read, + .attr_groups = arc_pmu->attr_groups, + }; + + if (has_interrupts) { + irq = platform_get_irq(pdev, 0); + if (irq >= 0) { + int ret; + + arc_pmu->irq = irq; + + /* intc map function ensures irq_set_percpu_devid() called */ + ret = request_percpu_irq(irq, arc_pmu_intr, "ARC perf counters", + this_cpu_ptr(&arc_pmu_cpu)); + + if (!ret) + on_each_cpu(arc_cpu_pmu_irq_init, &irq, 1); + else + irq = -1; + } + + } + + if (irq == -1) + arc_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; + + /* + * perf parser doesn't really like '-' symbol in events name, so let's + * use '_' in arc pct name as it goes to kernel PMU event prefix. + */ + return perf_pmu_register(&arc_pmu->pmu, "arc_pct", PERF_TYPE_RAW); +} + +static const struct of_device_id arc_pmu_match[] = { + { .compatible = "snps,arc700-pct" }, + { .compatible = "snps,archs-pct" }, + {}, +}; +MODULE_DEVICE_TABLE(of, arc_pmu_match); + +static struct platform_driver arc_pmu_driver = { + .driver = { + .name = "arc-pct", + .of_match_table = of_match_ptr(arc_pmu_match), + }, + .probe = arc_pmu_device_probe, +}; + +module_platform_driver(arc_pmu_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Mischa Jonker <mjonker@synopsys.com>"); +MODULE_DESCRIPTION("ARC PMU driver"); diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c new file mode 100644 index 000000000..8cf2caae9 --- /dev/null +++ b/arch/arc/kernel/process.c @@ -0,0 +1,303 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * Amit Bhor, Kanika Nema: Codito Technologies 2004 + */ + +#include <linux/errno.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/sched/task.h> +#include <linux/sched/task_stack.h> + +#include <linux/mm.h> +#include <linux/fs.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/syscalls.h> +#include <linux/elf.h> +#include <linux/tick.h> + +#include <asm/fpu.h> + +SYSCALL_DEFINE1(arc_settls, void *, user_tls_data_ptr) +{ + task_thread_info(current)->thr_ptr = (unsigned int)user_tls_data_ptr; + return 0; +} + +/* + * We return the user space TLS data ptr as sys-call return code + * Ideally it should be copy to user. + * However we can cheat by the fact that some sys-calls do return + * absurdly high values + * Since the tls dat aptr is not going to be in range of 0xFFFF_xxxx + * it won't be considered a sys-call error + * and it will be loads better than copy-to-user, which is a definite + * D-TLB Miss + */ +SYSCALL_DEFINE0(arc_gettls) +{ + return task_thread_info(current)->thr_ptr; +} + +SYSCALL_DEFINE3(arc_usr_cmpxchg, int __user *, uaddr, int, expected, int, new) +{ + struct pt_regs *regs = current_pt_regs(); + u32 uval; + int ret; + + /* + * This is only for old cores lacking LLOCK/SCOND, which by defintion + * can't possibly be SMP. Thus doesn't need to be SMP safe. + * And this also helps reduce the overhead for serializing in + * the UP case + */ + WARN_ON_ONCE(IS_ENABLED(CONFIG_SMP)); + + /* Z indicates to userspace if operation succeded */ + regs->status32 &= ~STATUS_Z_MASK; + + ret = access_ok(uaddr, sizeof(*uaddr)); + if (!ret) + goto fail; + +again: + preempt_disable(); + + ret = __get_user(uval, uaddr); + if (ret) + goto fault; + + if (uval != expected) + goto out; + + ret = __put_user(new, uaddr); + if (ret) + goto fault; + + regs->status32 |= STATUS_Z_MASK; + +out: + preempt_enable(); + return uval; + +fault: + preempt_enable(); + + if (unlikely(ret != -EFAULT)) + goto fail; + + mmap_read_lock(current->mm); + ret = fixup_user_fault(current->mm, (unsigned long) uaddr, + FAULT_FLAG_WRITE, NULL); + mmap_read_unlock(current->mm); + + if (likely(!ret)) + goto again; + +fail: + force_sig(SIGSEGV); + return ret; +} + +#ifdef CONFIG_ISA_ARCV2 + +void arch_cpu_idle(void) +{ + /* Re-enable interrupts <= default irq priority before commiting SLEEP */ + const unsigned int arg = 0x10 | ARCV2_IRQ_DEF_PRIO; + + __asm__ __volatile__( + "sleep %0 \n" + : + :"I"(arg)); /* can't be "r" has to be embedded const */ +} + +#else /* ARC700 */ + +void arch_cpu_idle(void) +{ + /* sleep, but enable both set E1/E2 (levels of interrutps) before committing */ + __asm__ __volatile__("sleep 0x3 \n"); +} + +#endif + +asmlinkage void ret_from_fork(void); + +/* + * Copy architecture-specific thread state + * + * Layout of Child kernel mode stack as setup at the end of this function is + * + * | ... | + * | ... | + * | unused | + * | | + * ------------------ + * | r25 | <==== top of Stack (thread.ksp) + * ~ ~ + * | --to-- | (CALLEE Regs of kernel mode) + * | r13 | + * ------------------ + * | fp | + * | blink | @ret_from_fork + * ------------------ + * | | + * ~ ~ + * ~ ~ + * | | + * ------------------ + * | r12 | + * ~ ~ + * | --to-- | (scratch Regs of user mode) + * | r0 | + * ------------------ + * | SP | + * | orig_r0 | + * | event/ECR | + * | user_r25 | + * ------------------ <===== END of PAGE + */ +int copy_thread(unsigned long clone_flags, unsigned long usp, + unsigned long kthread_arg, struct task_struct *p, + unsigned long tls) +{ + struct pt_regs *c_regs; /* child's pt_regs */ + unsigned long *childksp; /* to unwind out of __switch_to() */ + struct callee_regs *c_callee; /* child's callee regs */ + struct callee_regs *parent_callee; /* paren't callee */ + struct pt_regs *regs = current_pt_regs(); + + /* Mark the specific anchors to begin with (see pic above) */ + c_regs = task_pt_regs(p); + childksp = (unsigned long *)c_regs - 2; /* 2 words for FP/BLINK */ + c_callee = ((struct callee_regs *)childksp) - 1; + + /* + * __switch_to() uses thread.ksp to start unwinding stack + * For kernel threads we don't need to create callee regs, the + * stack layout nevertheless needs to remain the same. + * Also, since __switch_to anyways unwinds callee regs, we use + * this to populate kernel thread entry-pt/args into callee regs, + * so that ret_from_kernel_thread() becomes simpler. + */ + p->thread.ksp = (unsigned long)c_callee; /* THREAD_KSP */ + + /* __switch_to expects FP(0), BLINK(return addr) at top */ + childksp[0] = 0; /* fp */ + childksp[1] = (unsigned long)ret_from_fork; /* blink */ + + if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) { + memset(c_regs, 0, sizeof(struct pt_regs)); + + c_callee->r13 = kthread_arg; + c_callee->r14 = usp; /* function */ + + return 0; + } + + /*--------- User Task Only --------------*/ + + /* __switch_to expects FP(0), BLINK(return addr) at top of stack */ + childksp[0] = 0; /* for POP fp */ + childksp[1] = (unsigned long)ret_from_fork; /* for POP blink */ + + /* Copy parents pt regs on child's kernel mode stack */ + *c_regs = *regs; + + if (usp) + c_regs->sp = usp; + + c_regs->r0 = 0; /* fork returns 0 in child */ + + parent_callee = ((struct callee_regs *)regs) - 1; + *c_callee = *parent_callee; + + if (unlikely(clone_flags & CLONE_SETTLS)) { + /* + * set task's userland tls data ptr from 4th arg + * clone C-lib call is difft from clone sys-call + */ + task_thread_info(p)->thr_ptr = tls; + } else { + /* Normal fork case: set parent's TLS ptr in child */ + task_thread_info(p)->thr_ptr = + task_thread_info(current)->thr_ptr; + } + + + /* + * setup usermode thread pointer #1: + * when child is picked by scheduler, __switch_to() uses @c_callee to + * populate usermode callee regs: this works (despite being in a kernel + * function) since special return path for child @ret_from_fork() + * ensures those regs are not clobbered all the way to RTIE to usermode + */ + c_callee->r25 = task_thread_info(p)->thr_ptr; + +#ifdef CONFIG_ARC_CURR_IN_REG + /* + * setup usermode thread pointer #2: + * however for this special use of r25 in kernel, __switch_to() sets + * r25 for kernel needs and only in the final return path is usermode + * r25 setup, from pt_regs->user_r25. So set that up as well + */ + c_regs->user_r25 = c_callee->r25; +#endif + + return 0; +} + +/* + * Do necessary setup to start up a new user task + */ +void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp) +{ + regs->sp = usp; + regs->ret = pc; + + /* + * [U]ser Mode bit set + * [L] ZOL loop inhibited to begin with - cleared by a LP insn + * Interrupts enabled + */ + regs->status32 = STATUS_U_MASK | STATUS_L_MASK | ISA_INIT_STATUS_BITS; + + fpu_init_task(regs); + + /* bogus seed values for debugging */ + regs->lp_start = 0x10; + regs->lp_end = 0x80; +} + +/* + * Some archs flush debug and FPU info here + */ +void flush_thread(void) +{ +} + +int elf_check_arch(const struct elf32_hdr *x) +{ + unsigned int eflags; + + if (x->e_machine != EM_ARC_INUSE) { + pr_err("ELF not built for %s ISA\n", + is_isa_arcompact() ? "ARCompact":"ARCv2"); + return 0; + } + + eflags = x->e_flags; + if ((eflags & EF_ARC_OSABI_MSK) != EF_ARC_OSABI_CURRENT) { + pr_err("ABI mismatch - you need newer toolchain\n"); + force_sigsegv(SIGSEGV); + return 0; + } + + return 1; +} +EXPORT_SYMBOL(elf_check_arch); diff --git a/arch/arc/kernel/ptrace.c b/arch/arc/kernel/ptrace.c new file mode 100644 index 000000000..883391977 --- /dev/null +++ b/arch/arc/kernel/ptrace.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/ptrace.h> +#include <linux/tracehook.h> +#include <linux/sched/task_stack.h> +#include <linux/regset.h> +#include <linux/unistd.h> +#include <linux/elf.h> + +static struct callee_regs *task_callee_regs(struct task_struct *tsk) +{ + struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg; + return tmp; +} + +static int genregs_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + const struct pt_regs *ptregs = task_pt_regs(target); + const struct callee_regs *cregs = task_callee_regs(target); + unsigned int stop_pc_val; + + membuf_zero(&to, 4); // pad + membuf_store(&to, ptregs->bta); + membuf_store(&to, ptregs->lp_start); + membuf_store(&to, ptregs->lp_end); + membuf_store(&to, ptregs->lp_count); + membuf_store(&to, ptregs->status32); + membuf_store(&to, ptregs->ret); + membuf_store(&to, ptregs->blink); + membuf_store(&to, ptregs->fp); + membuf_store(&to, ptregs->r26); // gp + membuf_store(&to, ptregs->r12); + membuf_store(&to, ptregs->r11); + membuf_store(&to, ptregs->r10); + membuf_store(&to, ptregs->r9); + membuf_store(&to, ptregs->r8); + membuf_store(&to, ptregs->r7); + membuf_store(&to, ptregs->r6); + membuf_store(&to, ptregs->r5); + membuf_store(&to, ptregs->r4); + membuf_store(&to, ptregs->r3); + membuf_store(&to, ptregs->r2); + membuf_store(&to, ptregs->r1); + membuf_store(&to, ptregs->r0); + membuf_store(&to, ptregs->sp); + membuf_zero(&to, 4); // pad2 + membuf_store(&to, cregs->r25); + membuf_store(&to, cregs->r24); + membuf_store(&to, cregs->r23); + membuf_store(&to, cregs->r22); + membuf_store(&to, cregs->r21); + membuf_store(&to, cregs->r20); + membuf_store(&to, cregs->r19); + membuf_store(&to, cregs->r18); + membuf_store(&to, cregs->r17); + membuf_store(&to, cregs->r16); + membuf_store(&to, cregs->r15); + membuf_store(&to, cregs->r14); + membuf_store(&to, cregs->r13); + membuf_store(&to, target->thread.fault_address); // efa + + if (in_brkpt_trap(ptregs)) { + stop_pc_val = target->thread.fault_address; + pr_debug("\t\tstop_pc (brk-pt)\n"); + } else { + stop_pc_val = ptregs->ret; + pr_debug("\t\tstop_pc (others)\n"); + } + + return membuf_store(&to, stop_pc_val); // stop_pc +} + +static int genregs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + const struct pt_regs *ptregs = task_pt_regs(target); + const struct callee_regs *cregs = task_callee_regs(target); + int ret = 0; + +#define REG_IN_CHUNK(FIRST, NEXT, PTR) \ + if (!ret) \ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ + (void *)(PTR), \ + offsetof(struct user_regs_struct, FIRST), \ + offsetof(struct user_regs_struct, NEXT)); + +#define REG_IN_ONE(LOC, PTR) \ + if (!ret) \ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ + (void *)(PTR), \ + offsetof(struct user_regs_struct, LOC), \ + offsetof(struct user_regs_struct, LOC) + 4); + +#define REG_IGNORE_ONE(LOC) \ + if (!ret) \ + ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \ + offsetof(struct user_regs_struct, LOC), \ + offsetof(struct user_regs_struct, LOC) + 4); + + REG_IGNORE_ONE(pad); + + REG_IN_ONE(scratch.bta, &ptregs->bta); + REG_IN_ONE(scratch.lp_start, &ptregs->lp_start); + REG_IN_ONE(scratch.lp_end, &ptregs->lp_end); + REG_IN_ONE(scratch.lp_count, &ptregs->lp_count); + + REG_IGNORE_ONE(scratch.status32); + + REG_IN_ONE(scratch.ret, &ptregs->ret); + REG_IN_ONE(scratch.blink, &ptregs->blink); + REG_IN_ONE(scratch.fp, &ptregs->fp); + REG_IN_ONE(scratch.gp, &ptregs->r26); + REG_IN_ONE(scratch.r12, &ptregs->r12); + REG_IN_ONE(scratch.r11, &ptregs->r11); + REG_IN_ONE(scratch.r10, &ptregs->r10); + REG_IN_ONE(scratch.r9, &ptregs->r9); + REG_IN_ONE(scratch.r8, &ptregs->r8); + REG_IN_ONE(scratch.r7, &ptregs->r7); + REG_IN_ONE(scratch.r6, &ptregs->r6); + REG_IN_ONE(scratch.r5, &ptregs->r5); + REG_IN_ONE(scratch.r4, &ptregs->r4); + REG_IN_ONE(scratch.r3, &ptregs->r3); + REG_IN_ONE(scratch.r2, &ptregs->r2); + REG_IN_ONE(scratch.r1, &ptregs->r1); + REG_IN_ONE(scratch.r0, &ptregs->r0); + REG_IN_ONE(scratch.sp, &ptregs->sp); + + REG_IGNORE_ONE(pad2); + + REG_IN_ONE(callee.r25, &cregs->r25); + REG_IN_ONE(callee.r24, &cregs->r24); + REG_IN_ONE(callee.r23, &cregs->r23); + REG_IN_ONE(callee.r22, &cregs->r22); + REG_IN_ONE(callee.r21, &cregs->r21); + REG_IN_ONE(callee.r20, &cregs->r20); + REG_IN_ONE(callee.r19, &cregs->r19); + REG_IN_ONE(callee.r18, &cregs->r18); + REG_IN_ONE(callee.r17, &cregs->r17); + REG_IN_ONE(callee.r16, &cregs->r16); + REG_IN_ONE(callee.r15, &cregs->r15); + REG_IN_ONE(callee.r14, &cregs->r14); + REG_IN_ONE(callee.r13, &cregs->r13); + + REG_IGNORE_ONE(efa); /* efa update invalid */ + REG_IGNORE_ONE(stop_pc); /* PC updated via @ret */ + + return ret; +} + +#ifdef CONFIG_ISA_ARCV2 +static int arcv2regs_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + const struct pt_regs *regs = task_pt_regs(target); + + if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS)) + /* + * itemized copy not needed like above as layout of regs (r30,r58,r59) + * is exactly same in kernel (pt_regs) and userspace (user_regs_arcv2) + */ + return membuf_write(&to, ®s->r30, sizeof(struct user_regs_arcv2)); + + + membuf_write(&to, ®s->r30, 4); /* r30 only */ + return membuf_zero(&to, sizeof(struct user_regs_arcv2) - 4); +} + +static int arcv2regs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + const struct pt_regs *regs = task_pt_regs(target); + int ret, copy_sz; + + if (IS_ENABLED(CONFIG_ARC_HAS_ACCL_REGS)) + copy_sz = sizeof(struct user_regs_arcv2); + else + copy_sz = 4; /* r30 only */ + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, (void *)®s->r30, + 0, copy_sz); + + return ret; +} + +#endif + +enum arc_getset { + REGSET_CMN, + REGSET_ARCV2, +}; + +static const struct user_regset arc_regsets[] = { + [REGSET_CMN] = { + .core_note_type = NT_PRSTATUS, + .n = ELF_NGREG, + .size = sizeof(unsigned long), + .align = sizeof(unsigned long), + .regset_get = genregs_get, + .set = genregs_set, + }, +#ifdef CONFIG_ISA_ARCV2 + [REGSET_ARCV2] = { + .core_note_type = NT_ARC_V2, + .n = ELF_ARCV2REG, + .size = sizeof(unsigned long), + .align = sizeof(unsigned long), + .regset_get = arcv2regs_get, + .set = arcv2regs_set, + }, +#endif +}; + +static const struct user_regset_view user_arc_view = { + .name = "arc", + .e_machine = EM_ARC_INUSE, + .regsets = arc_regsets, + .n = ARRAY_SIZE(arc_regsets) +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &user_arc_view; +} + +void ptrace_disable(struct task_struct *child) +{ +} + +long arch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + int ret = -EIO; + + pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data); + + switch (request) { + case PTRACE_GET_THREAD_AREA: + ret = put_user(task_thread_info(child)->thr_ptr, + (unsigned long __user *)data); + break; + default: + ret = ptrace_request(child, request, addr, data); + break; + } + + return ret; +} + +asmlinkage int syscall_trace_entry(struct pt_regs *regs) +{ + if (tracehook_report_syscall_entry(regs)) + return ULONG_MAX; + + return regs->r8; +} + +asmlinkage void syscall_trace_exit(struct pt_regs *regs) +{ + tracehook_report_syscall_exit(regs, 0); +} diff --git a/arch/arc/kernel/reset.c b/arch/arc/kernel/reset.c new file mode 100644 index 000000000..fd6c3eb93 --- /dev/null +++ b/arch/arc/kernel/reset.c @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/kernel.h> +#include <linux/printk.h> +#include <linux/reboot.h> +#include <linux/pm.h> + +void machine_halt(void) +{ + /* Halt the processor */ + __asm__ __volatile__("flag 1\n"); +} + +void machine_restart(char *__unused) +{ + /* Soft reset : jump to reset vector */ + pr_info("Put your restart handler here\n"); + machine_halt(); +} + +void machine_power_off(void) +{ + /* FIXME :: power off ??? */ + machine_halt(); +} + +void (*pm_power_off) (void) = NULL; +EXPORT_SYMBOL(pm_power_off); diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c new file mode 100644 index 000000000..41f07b3e5 --- /dev/null +++ b/arch/arc/kernel/setup.c @@ -0,0 +1,701 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/seq_file.h> +#include <linux/fs.h> +#include <linux/delay.h> +#include <linux/root_dev.h> +#include <linux/clk.h> +#include <linux/clocksource.h> +#include <linux/console.h> +#include <linux/module.h> +#include <linux/sizes.h> +#include <linux/cpu.h> +#include <linux/of_clk.h> +#include <linux/of_fdt.h> +#include <linux/of.h> +#include <linux/cache.h> +#include <uapi/linux/mount.h> +#include <asm/sections.h> +#include <asm/arcregs.h> +#include <asm/asserts.h> +#include <asm/tlb.h> +#include <asm/setup.h> +#include <asm/page.h> +#include <asm/irq.h> +#include <asm/unwind.h> +#include <asm/mach_desc.h> +#include <asm/smp.h> +#include <asm/dsp-impl.h> + +#define FIX_PTR(x) __asm__ __volatile__(";" : "+r"(x)) + +unsigned int intr_to_DE_cnt; + +/* Part of U-boot ABI: see head.S */ +int __initdata uboot_tag; +int __initdata uboot_magic; +char __initdata *uboot_arg; + +const struct machine_desc *machine_desc; + +struct task_struct *_current_task[NR_CPUS]; /* For stack switching */ + +struct cpuinfo_arc cpuinfo_arc700[NR_CPUS]; + +static const struct id_to_str arc_legacy_rel[] = { + /* ID.ARCVER, Release */ +#ifdef CONFIG_ISA_ARCOMPACT + { 0x34, "R4.10"}, + { 0x35, "R4.11"}, +#else + { 0x51, "R2.0" }, + { 0x52, "R2.1" }, + { 0x53, "R3.0" }, +#endif + { 0x00, NULL } +}; + +static const struct id_to_str arc_hs_ver54_rel[] = { + /* UARCH.MAJOR, Release */ + { 0, "R3.10a"}, + { 1, "R3.50a"}, + { 2, "R3.60a"}, + { 3, "R4.00a"}, + { 0xFF, NULL } +}; + +static void read_decode_ccm_bcr(struct cpuinfo_arc *cpu) +{ + if (is_isa_arcompact()) { + struct bcr_iccm_arcompact iccm; + struct bcr_dccm_arcompact dccm; + + READ_BCR(ARC_REG_ICCM_BUILD, iccm); + if (iccm.ver) { + cpu->iccm.sz = 4096 << iccm.sz; /* 8K to 512K */ + cpu->iccm.base_addr = iccm.base << 16; + } + + READ_BCR(ARC_REG_DCCM_BUILD, dccm); + if (dccm.ver) { + unsigned long base; + cpu->dccm.sz = 2048 << dccm.sz; /* 2K to 256K */ + + base = read_aux_reg(ARC_REG_DCCM_BASE_BUILD); + cpu->dccm.base_addr = base & ~0xF; + } + } else { + struct bcr_iccm_arcv2 iccm; + struct bcr_dccm_arcv2 dccm; + unsigned long region; + + READ_BCR(ARC_REG_ICCM_BUILD, iccm); + if (iccm.ver) { + cpu->iccm.sz = 256 << iccm.sz00; /* 512B to 16M */ + if (iccm.sz00 == 0xF && iccm.sz01 > 0) + cpu->iccm.sz <<= iccm.sz01; + + region = read_aux_reg(ARC_REG_AUX_ICCM); + cpu->iccm.base_addr = region & 0xF0000000; + } + + READ_BCR(ARC_REG_DCCM_BUILD, dccm); + if (dccm.ver) { + cpu->dccm.sz = 256 << dccm.sz0; + if (dccm.sz0 == 0xF && dccm.sz1 > 0) + cpu->dccm.sz <<= dccm.sz1; + + region = read_aux_reg(ARC_REG_AUX_DCCM); + cpu->dccm.base_addr = region & 0xF0000000; + } + } +} + +static void decode_arc_core(struct cpuinfo_arc *cpu) +{ + struct bcr_uarch_build_arcv2 uarch; + const struct id_to_str *tbl; + + if (cpu->core.family < 0x54) { /* includes arc700 */ + + for (tbl = &arc_legacy_rel[0]; tbl->id != 0; tbl++) { + if (cpu->core.family == tbl->id) { + cpu->release = tbl->str; + break; + } + } + + if (is_isa_arcompact()) + cpu->name = "ARC700"; + else if (tbl->str) + cpu->name = "HS38"; + else + cpu->name = cpu->release = "Unknown"; + + return; + } + + /* + * Initial HS cores bumped AUX IDENTITY.ARCVER for each release until + * ARCVER 0x54 which introduced AUX MICRO_ARCH_BUILD and subsequent + * releases only update it. + */ + READ_BCR(ARC_REG_MICRO_ARCH_BCR, uarch); + + if (uarch.prod == 4) { + cpu->name = "HS48"; + cpu->extn.dual = 1; + + } else { + cpu->name = "HS38"; + } + + for (tbl = &arc_hs_ver54_rel[0]; tbl->id != 0xFF; tbl++) { + if (uarch.maj == tbl->id) { + cpu->release = tbl->str; + break; + } + } +} + +static void read_arc_build_cfg_regs(void) +{ + struct bcr_timer timer; + struct bcr_generic bcr; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + struct bcr_isa_arcv2 isa; + struct bcr_actionpoint ap; + + FIX_PTR(cpu); + + READ_BCR(AUX_IDENTITY, cpu->core); + decode_arc_core(cpu); + + READ_BCR(ARC_REG_TIMERS_BCR, timer); + cpu->extn.timer0 = timer.t0; + cpu->extn.timer1 = timer.t1; + cpu->extn.rtc = timer.rtc; + + cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE); + + READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy); + + /* Read CCM BCRs for boot reporting even if not enabled in Kconfig */ + read_decode_ccm_bcr(cpu); + + read_decode_mmu_bcr(); + read_decode_cache_bcr(); + + if (is_isa_arcompact()) { + struct bcr_fp_arcompact sp, dp; + struct bcr_bpu_arcompact bpu; + + READ_BCR(ARC_REG_FP_BCR, sp); + READ_BCR(ARC_REG_DPFP_BCR, dp); + cpu->extn.fpu_sp = sp.ver ? 1 : 0; + cpu->extn.fpu_dp = dp.ver ? 1 : 0; + + READ_BCR(ARC_REG_BPU_BCR, bpu); + cpu->bpu.ver = bpu.ver; + cpu->bpu.full = bpu.fam ? 1 : 0; + if (bpu.ent) { + cpu->bpu.num_cache = 256 << (bpu.ent - 1); + cpu->bpu.num_pred = 256 << (bpu.ent - 1); + } + } else { + struct bcr_fp_arcv2 spdp; + struct bcr_bpu_arcv2 bpu; + + READ_BCR(ARC_REG_FP_V2_BCR, spdp); + cpu->extn.fpu_sp = spdp.sp ? 1 : 0; + cpu->extn.fpu_dp = spdp.dp ? 1 : 0; + + READ_BCR(ARC_REG_BPU_BCR, bpu); + cpu->bpu.ver = bpu.ver; + cpu->bpu.full = bpu.ft; + cpu->bpu.num_cache = 256 << bpu.bce; + cpu->bpu.num_pred = 2048 << bpu.pte; + cpu->bpu.ret_stk = 4 << bpu.rse; + + /* if dual issue hardware, is it enabled ? */ + if (cpu->extn.dual) { + unsigned int exec_ctrl; + + READ_BCR(AUX_EXEC_CTRL, exec_ctrl); + cpu->extn.dual_enb = !(exec_ctrl & 1); + } + } + + READ_BCR(ARC_REG_AP_BCR, ap); + if (ap.ver) { + cpu->extn.ap_num = 2 << ap.num; + cpu->extn.ap_full = !ap.min; + } + + READ_BCR(ARC_REG_SMART_BCR, bcr); + cpu->extn.smart = bcr.ver ? 1 : 0; + + READ_BCR(ARC_REG_RTT_BCR, bcr); + cpu->extn.rtt = bcr.ver ? 1 : 0; + + READ_BCR(ARC_REG_ISA_CFG_BCR, isa); + + /* some hacks for lack of feature BCR info in old ARC700 cores */ + if (is_isa_arcompact()) { + if (!isa.ver) /* ISA BCR absent, use Kconfig info */ + cpu->isa.atomic = IS_ENABLED(CONFIG_ARC_HAS_LLSC); + else { + /* ARC700_BUILD only has 2 bits of isa info */ + struct bcr_generic bcr = *(struct bcr_generic *)&isa; + cpu->isa.atomic = bcr.info & 1; + } + + cpu->isa.be = IS_ENABLED(CONFIG_CPU_BIG_ENDIAN); + + /* there's no direct way to distinguish 750 vs. 770 */ + if (unlikely(cpu->core.family < 0x34 || cpu->mmu.ver < 3)) + cpu->name = "ARC750"; + } else { + cpu->isa = isa; + } +} + +static char *arc_cpu_mumbojumbo(int cpu_id, char *buf, int len) +{ + struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id]; + struct bcr_identity *core = &cpu->core; + char mpy_opt[16]; + int n = 0; + + FIX_PTR(cpu); + + n += scnprintf(buf + n, len - n, + "\nIDENTITY\t: ARCVER [%#02x] ARCNUM [%#02x] CHIPID [%#4x]\n", + core->family, core->cpu_id, core->chip_id); + + n += scnprintf(buf + n, len - n, "processor [%d]\t: %s %s (%s ISA) %s%s%s\n", + cpu_id, cpu->name, cpu->release, + is_isa_arcompact() ? "ARCompact" : "ARCv2", + IS_AVAIL1(cpu->isa.be, "[Big-Endian]"), + IS_AVAIL3(cpu->extn.dual, cpu->extn.dual_enb, " Dual-Issue ")); + + n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s%s%s\nISA Extn\t: ", + IS_AVAIL1(cpu->extn.timer0, "Timer0 "), + IS_AVAIL1(cpu->extn.timer1, "Timer1 "), + IS_AVAIL2(cpu->extn.rtc, "RTC [UP 64-bit] ", CONFIG_ARC_TIMERS_64BIT), + IS_AVAIL2(cpu->extn.gfrc, "GFRC [SMP 64-bit] ", CONFIG_ARC_TIMERS_64BIT)); + + if (cpu->extn_mpy.ver) { + if (is_isa_arcompact()) { + scnprintf(mpy_opt, 16, "mpy"); + } else { + + int opt = 2; /* stock MPY/MPYH */ + + if (cpu->extn_mpy.dsp) /* OPT 7-9 */ + opt = cpu->extn_mpy.dsp + 6; + + scnprintf(mpy_opt, 16, "mpy[opt %d] ", opt); + } + } + + n += scnprintf(buf + n, len - n, "%s%s%s%s%s%s%s%s\n", + IS_AVAIL2(cpu->isa.atomic, "atomic ", CONFIG_ARC_HAS_LLSC), + IS_AVAIL2(cpu->isa.ldd, "ll64 ", CONFIG_ARC_HAS_LL64), + IS_AVAIL2(cpu->isa.unalign, "unalign ", CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS), + IS_AVAIL1(cpu->extn_mpy.ver, mpy_opt), + IS_AVAIL1(cpu->isa.div_rem, "div_rem ")); + + if (cpu->bpu.ver) { + n += scnprintf(buf + n, len - n, + "BPU\t\t: %s%s match, cache:%d, Predict Table:%d Return stk: %d", + IS_AVAIL1(cpu->bpu.full, "full"), + IS_AVAIL1(!cpu->bpu.full, "partial"), + cpu->bpu.num_cache, cpu->bpu.num_pred, cpu->bpu.ret_stk); + + if (is_isa_arcv2()) { + struct bcr_lpb lpb; + + READ_BCR(ARC_REG_LPB_BUILD, lpb); + if (lpb.ver) { + unsigned int ctl; + ctl = read_aux_reg(ARC_REG_LPB_CTRL); + + n += scnprintf(buf + n, len - n, " Loop Buffer:%d %s", + lpb.entries, + IS_DISABLED_RUN(!ctl)); + } + } + n += scnprintf(buf + n, len - n, "\n"); + } + + return buf; +} + +static char *arc_extn_mumbojumbo(int cpu_id, char *buf, int len) +{ + int n = 0; + struct cpuinfo_arc *cpu = &cpuinfo_arc700[cpu_id]; + + FIX_PTR(cpu); + + n += scnprintf(buf + n, len - n, "Vector Table\t: %#x\n", cpu->vec_base); + + if (cpu->extn.fpu_sp || cpu->extn.fpu_dp) + n += scnprintf(buf + n, len - n, "FPU\t\t: %s%s\n", + IS_AVAIL1(cpu->extn.fpu_sp, "SP "), + IS_AVAIL1(cpu->extn.fpu_dp, "DP ")); + + if (cpu->extn.ap_num | cpu->extn.smart | cpu->extn.rtt) { + n += scnprintf(buf + n, len - n, "DEBUG\t\t: %s%s", + IS_AVAIL1(cpu->extn.smart, "smaRT "), + IS_AVAIL1(cpu->extn.rtt, "RTT ")); + if (cpu->extn.ap_num) { + n += scnprintf(buf + n, len - n, "ActionPoint %d/%s", + cpu->extn.ap_num, + cpu->extn.ap_full ? "full":"min"); + } + n += scnprintf(buf + n, len - n, "\n"); + } + + if (cpu->dccm.sz || cpu->iccm.sz) + n += scnprintf(buf + n, len - n, "Extn [CCM]\t: DCCM @ %x, %d KB / ICCM: @ %x, %d KB\n", + cpu->dccm.base_addr, TO_KB(cpu->dccm.sz), + cpu->iccm.base_addr, TO_KB(cpu->iccm.sz)); + + if (is_isa_arcv2()) { + + /* Error Protection: ECC/Parity */ + struct bcr_erp erp; + READ_BCR(ARC_REG_ERP_BUILD, erp); + + if (erp.ver) { + struct ctl_erp ctl; + READ_BCR(ARC_REG_ERP_CTRL, ctl); + + /* inverted bits: 0 means enabled */ + n += scnprintf(buf + n, len - n, "Extn [ECC]\t: %s%s%s%s%s%s\n", + IS_AVAIL3(erp.ic, !ctl.dpi, "IC "), + IS_AVAIL3(erp.dc, !ctl.dpd, "DC "), + IS_AVAIL3(erp.mmu, !ctl.mpd, "MMU ")); + } + } + + return buf; +} + +void chk_opt_strict(char *opt_name, bool hw_exists, bool opt_ena) +{ + if (hw_exists && !opt_ena) + pr_warn(" ! Enable %s for working apps\n", opt_name); + else if (!hw_exists && opt_ena) + panic("Disable %s, hardware NOT present\n", opt_name); +} + +void chk_opt_weak(char *opt_name, bool hw_exists, bool opt_ena) +{ + if (!hw_exists && opt_ena) + panic("Disable %s, hardware NOT present\n", opt_name); +} + +static void arc_chk_core_config(void) +{ + struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + int present = 0; + + if (!cpu->extn.timer0) + panic("Timer0 is not present!\n"); + + if (!cpu->extn.timer1) + panic("Timer1 is not present!\n"); + +#ifdef CONFIG_ARC_HAS_DCCM + /* + * DCCM can be arbit placed in hardware. + * Make sure it's placement/sz matches what Linux is built with + */ + if ((unsigned int)__arc_dccm_base != cpu->dccm.base_addr) + panic("Linux built with incorrect DCCM Base address\n"); + + if (CONFIG_ARC_DCCM_SZ * SZ_1K != cpu->dccm.sz) + panic("Linux built with incorrect DCCM Size\n"); +#endif + +#ifdef CONFIG_ARC_HAS_ICCM + if (CONFIG_ARC_ICCM_SZ * SZ_1K != cpu->iccm.sz) + panic("Linux built with incorrect ICCM Size\n"); +#endif + + /* + * FP hardware/software config sanity + * -If hardware present, kernel needs to save/restore FPU state + * -If not, it will crash trying to save/restore the non-existant regs + */ + + if (is_isa_arcompact()) { + /* only DPDP checked since SP has no arch visible regs */ + present = cpu->extn.fpu_dp; + CHK_OPT_STRICT(CONFIG_ARC_FPU_SAVE_RESTORE, present); + } else { + /* Accumulator Low:High pair (r58:59) present if DSP MPY or FPU */ + present = cpu->extn_mpy.dsp | cpu->extn.fpu_sp | cpu->extn.fpu_dp; + CHK_OPT_STRICT(CONFIG_ARC_HAS_ACCL_REGS, present); + + dsp_config_check(); + } +} + +/* + * Initialize and setup the processor core + * This is called by all the CPUs thus should not do special case stuff + * such as only for boot CPU etc + */ + +void setup_processor(void) +{ + char str[512]; + int cpu_id = smp_processor_id(); + + read_arc_build_cfg_regs(); + arc_init_IRQ(); + + pr_info("%s", arc_cpu_mumbojumbo(cpu_id, str, sizeof(str))); + + arc_mmu_init(); + arc_cache_init(); + + pr_info("%s", arc_extn_mumbojumbo(cpu_id, str, sizeof(str))); + pr_info("%s", arc_platform_smp_cpuinfo()); + + arc_chk_core_config(); +} + +static inline bool uboot_arg_invalid(unsigned long addr) +{ + /* + * Check that it is a untranslated address (although MMU is not enabled + * yet, it being a high address ensures this is not by fluke) + */ + if (addr < PAGE_OFFSET) + return true; + + /* Check that address doesn't clobber resident kernel image */ + return addr >= (unsigned long)_stext && addr <= (unsigned long)_end; +} + +#define IGNORE_ARGS "Ignore U-boot args: " + +/* uboot_tag values for U-boot - kernel ABI revision 0; see head.S */ +#define UBOOT_TAG_NONE 0 +#define UBOOT_TAG_CMDLINE 1 +#define UBOOT_TAG_DTB 2 +/* We always pass 0 as magic from U-boot */ +#define UBOOT_MAGIC_VALUE 0 + +void __init handle_uboot_args(void) +{ + bool use_embedded_dtb = true; + bool append_cmdline = false; + + /* check that we know this tag */ + if (uboot_tag != UBOOT_TAG_NONE && + uboot_tag != UBOOT_TAG_CMDLINE && + uboot_tag != UBOOT_TAG_DTB) { + pr_warn(IGNORE_ARGS "invalid uboot tag: '%08x'\n", uboot_tag); + goto ignore_uboot_args; + } + + if (uboot_magic != UBOOT_MAGIC_VALUE) { + pr_warn(IGNORE_ARGS "non zero uboot magic\n"); + goto ignore_uboot_args; + } + + if (uboot_tag != UBOOT_TAG_NONE && + uboot_arg_invalid((unsigned long)uboot_arg)) { + pr_warn(IGNORE_ARGS "invalid uboot arg: '%px'\n", uboot_arg); + goto ignore_uboot_args; + } + + /* see if U-boot passed an external Device Tree blob */ + if (uboot_tag == UBOOT_TAG_DTB) { + machine_desc = setup_machine_fdt((void *)uboot_arg); + + /* external Device Tree blob is invalid - use embedded one */ + use_embedded_dtb = !machine_desc; + } + + if (uboot_tag == UBOOT_TAG_CMDLINE) + append_cmdline = true; + +ignore_uboot_args: + + if (use_embedded_dtb) { + machine_desc = setup_machine_fdt(__dtb_start); + if (!machine_desc) + panic("Embedded DT invalid\n"); + } + + /* + * NOTE: @boot_command_line is populated by setup_machine_fdt() so this + * append processing can only happen after. + */ + if (append_cmdline) { + /* Ensure a whitespace between the 2 cmdlines */ + strlcat(boot_command_line, " ", COMMAND_LINE_SIZE); + strlcat(boot_command_line, uboot_arg, COMMAND_LINE_SIZE); + } +} + +void __init setup_arch(char **cmdline_p) +{ + handle_uboot_args(); + + /* Save unparsed command line copy for /proc/cmdline */ + *cmdline_p = boot_command_line; + + /* To force early parsing of things like mem=xxx */ + parse_early_param(); + + /* Platform/board specific: e.g. early console registration */ + if (machine_desc->init_early) + machine_desc->init_early(); + + smp_init_cpus(); + + setup_processor(); + setup_arch_memory(); + + /* copy flat DT out of .init and then unflatten it */ + unflatten_and_copy_device_tree(); + + /* Can be issue if someone passes cmd line arg "ro" + * But that is unlikely so keeping it as it is + */ + root_mountflags &= ~MS_RDONLY; + + arc_unwind_init(); +} + +/* + * Called from start_kernel() - boot CPU only + */ +void __init time_init(void) +{ + of_clk_init(NULL); + timer_probe(); +} + +static int __init customize_machine(void) +{ + if (machine_desc->init_machine) + machine_desc->init_machine(); + + return 0; +} +arch_initcall(customize_machine); + +static int __init init_late_machine(void) +{ + if (machine_desc->init_late) + machine_desc->init_late(); + + return 0; +} +late_initcall(init_late_machine); +/* + * Get CPU information for use by the procfs. + */ + +#define cpu_to_ptr(c) ((void *)(0xFFFF0000 | (unsigned int)(c))) +#define ptr_to_cpu(p) (~0xFFFF0000UL & (unsigned int)(p)) + +static int show_cpuinfo(struct seq_file *m, void *v) +{ + char *str; + int cpu_id = ptr_to_cpu(v); + struct device *cpu_dev = get_cpu_device(cpu_id); + struct clk *cpu_clk; + unsigned long freq = 0; + + if (!cpu_online(cpu_id)) { + seq_printf(m, "processor [%d]\t: Offline\n", cpu_id); + goto done; + } + + str = (char *)__get_free_page(GFP_KERNEL); + if (!str) + goto done; + + seq_printf(m, arc_cpu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + + cpu_clk = clk_get(cpu_dev, NULL); + if (IS_ERR(cpu_clk)) { + seq_printf(m, "CPU speed \t: Cannot get clock for processor [%d]\n", + cpu_id); + } else { + freq = clk_get_rate(cpu_clk); + } + if (freq) + seq_printf(m, "CPU speed\t: %lu.%02lu Mhz\n", + freq / 1000000, (freq / 10000) % 100); + + seq_printf(m, "Bogo MIPS\t: %lu.%02lu\n", + loops_per_jiffy / (500000 / HZ), + (loops_per_jiffy / (5000 / HZ)) % 100); + + seq_printf(m, arc_mmu_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, arc_cache_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, arc_extn_mumbojumbo(cpu_id, str, PAGE_SIZE)); + seq_printf(m, arc_platform_smp_cpuinfo()); + + free_page((unsigned long)str); +done: + seq_printf(m, "\n"); + + return 0; +} + +static void *c_start(struct seq_file *m, loff_t *pos) +{ + /* + * Callback returns cpu-id to iterator for show routine, NULL to stop. + * However since NULL is also a valid cpu-id (0), we use a round-about + * way to pass it w/o having to kmalloc/free a 2 byte string. + * Encode cpu-id as 0xFFcccc, which is decoded by show routine. + */ + return *pos < nr_cpu_ids ? cpu_to_ptr(*pos) : NULL; +} + +static void *c_next(struct seq_file *m, void *v, loff_t *pos) +{ + ++*pos; + return c_start(m, pos); +} + +static void c_stop(struct seq_file *m, void *v) +{ +} + +const struct seq_operations cpuinfo_op = { + .start = c_start, + .next = c_next, + .stop = c_stop, + .show = show_cpuinfo +}; + +static DEFINE_PER_CPU(struct cpu, cpu_topology); + +static int __init topology_init(void) +{ + int cpu; + + for_each_present_cpu(cpu) + register_cpu(&per_cpu(cpu_topology, cpu), cpu); + + return 0; +} + +subsys_initcall(topology_init); diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c new file mode 100644 index 000000000..c43d323bc --- /dev/null +++ b/arch/arc/kernel/signal.c @@ -0,0 +1,442 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Signal Handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * vineetg: Jan 2010 (Restarting of timer related syscalls) + * + * vineetg: Nov 2009 (Everything needed for TIF_RESTORE_SIGMASK) + * -do_signal() supports TIF_RESTORE_SIGMASK + * -do_signal() no loner needs oldset, required by OLD sys_sigsuspend + * -sys_rt_sigsuspend() now comes from generic code, so discard arch implemen + * -sys_sigsuspend() no longer needs to fudge ptregs, hence that arg removed + * -sys_sigsuspend() no longer loops for do_signal(), sets TIF_xxx and leaves + * the job to do_signal() + * + * vineetg: July 2009 + * -Modified Code to support the uClibc provided userland sigreturn stub + * to avoid kernel synthesing it on user stack at runtime, costing TLB + * probes and Cache line flushes. + * + * vineetg: July 2009 + * -In stash_usr_regs( ) and restore_usr_regs( ), save/restore of user regs + * in done in block copy rather than one word at a time. + * This saves around 2K of code and improves LMBench lat_sig <catch> + * + * rajeshwarr: Feb 2009 + * - Support for Realtime Signals + * + * vineetg: Aug 11th 2008: Bug #94183 + * -ViXS were still seeing crashes when using insmod to load drivers. + * It turned out that the code to change Execute permssions for TLB entries + * of user was not guarded for interrupts (mod_tlb_permission) + * This was causing TLB entries to be overwritten on unrelated indexes + * + * Vineetg: July 15th 2008: Bug #94183 + * -Exception happens in Delay slot of a JMP, and before user space resumes, + * Signal is delivered (Ctrl + C) = >SIGINT. + * setup_frame( ) sets up PC,SP,BLINK to enable user space signal handler + * to run, but doesn't clear the Delay slot bit from status32. As a result, + * on resuming user mode, signal handler branches off to BTA of orig JMP + * -FIX: clear the DE bit from status32 in setup_frame( ) + * + * Rahul Trivedi, Kanika Nema: Codito Technologies 2004 + */ + +#include <linux/signal.h> +#include <linux/ptrace.h> +#include <linux/personality.h> +#include <linux/uaccess.h> +#include <linux/syscalls.h> +#include <linux/tracehook.h> +#include <linux/sched/task_stack.h> + +#include <asm/ucontext.h> + +struct rt_sigframe { + struct siginfo info; + struct ucontext uc; +#define MAGIC_SIGALTSTK 0x07302004 + unsigned int sigret_magic; +}; + +static int save_arcv2_regs(struct sigcontext __user *mctx, struct pt_regs *regs) +{ + int err = 0; +#ifndef CONFIG_ISA_ARCOMPACT + struct user_regs_arcv2 v2abi; + + v2abi.r30 = regs->r30; +#ifdef CONFIG_ARC_HAS_ACCL_REGS + v2abi.r58 = regs->r58; + v2abi.r59 = regs->r59; +#else + v2abi.r58 = v2abi.r59 = 0; +#endif + err = __copy_to_user(&mctx->v2abi, (void const *)&v2abi, sizeof(v2abi)); +#endif + return err; +} + +static int restore_arcv2_regs(struct sigcontext __user *mctx, struct pt_regs *regs) +{ + int err = 0; +#ifndef CONFIG_ISA_ARCOMPACT + struct user_regs_arcv2 v2abi; + + err = __copy_from_user(&v2abi, &mctx->v2abi, sizeof(v2abi)); + + regs->r30 = v2abi.r30; +#ifdef CONFIG_ARC_HAS_ACCL_REGS + regs->r58 = v2abi.r58; + regs->r59 = v2abi.r59; +#endif +#endif + return err; +} + +static int +stash_usr_regs(struct rt_sigframe __user *sf, struct pt_regs *regs, + sigset_t *set) +{ + int err; + struct user_regs_struct uregs; + + uregs.scratch.bta = regs->bta; + uregs.scratch.lp_start = regs->lp_start; + uregs.scratch.lp_end = regs->lp_end; + uregs.scratch.lp_count = regs->lp_count; + uregs.scratch.status32 = regs->status32; + uregs.scratch.ret = regs->ret; + uregs.scratch.blink = regs->blink; + uregs.scratch.fp = regs->fp; + uregs.scratch.gp = regs->r26; + uregs.scratch.r12 = regs->r12; + uregs.scratch.r11 = regs->r11; + uregs.scratch.r10 = regs->r10; + uregs.scratch.r9 = regs->r9; + uregs.scratch.r8 = regs->r8; + uregs.scratch.r7 = regs->r7; + uregs.scratch.r6 = regs->r6; + uregs.scratch.r5 = regs->r5; + uregs.scratch.r4 = regs->r4; + uregs.scratch.r3 = regs->r3; + uregs.scratch.r2 = regs->r2; + uregs.scratch.r1 = regs->r1; + uregs.scratch.r0 = regs->r0; + uregs.scratch.sp = regs->sp; + + err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), &uregs.scratch, + sizeof(sf->uc.uc_mcontext.regs.scratch)); + + if (is_isa_arcv2()) + err |= save_arcv2_regs(&(sf->uc.uc_mcontext), regs); + + err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t)); + + return err ? -EFAULT : 0; +} + +static int restore_usr_regs(struct pt_regs *regs, struct rt_sigframe __user *sf) +{ + sigset_t set; + int err; + struct user_regs_struct uregs; + + err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); + err |= __copy_from_user(&uregs.scratch, + &(sf->uc.uc_mcontext.regs.scratch), + sizeof(sf->uc.uc_mcontext.regs.scratch)); + + if (is_isa_arcv2()) + err |= restore_arcv2_regs(&(sf->uc.uc_mcontext), regs); + + if (err) + return -EFAULT; + + set_current_blocked(&set); + regs->bta = uregs.scratch.bta; + regs->lp_start = uregs.scratch.lp_start; + regs->lp_end = uregs.scratch.lp_end; + regs->lp_count = uregs.scratch.lp_count; + regs->status32 = uregs.scratch.status32; + regs->ret = uregs.scratch.ret; + regs->blink = uregs.scratch.blink; + regs->fp = uregs.scratch.fp; + regs->r26 = uregs.scratch.gp; + regs->r12 = uregs.scratch.r12; + regs->r11 = uregs.scratch.r11; + regs->r10 = uregs.scratch.r10; + regs->r9 = uregs.scratch.r9; + regs->r8 = uregs.scratch.r8; + regs->r7 = uregs.scratch.r7; + regs->r6 = uregs.scratch.r6; + regs->r5 = uregs.scratch.r5; + regs->r4 = uregs.scratch.r4; + regs->r3 = uregs.scratch.r3; + regs->r2 = uregs.scratch.r2; + regs->r1 = uregs.scratch.r1; + regs->r0 = uregs.scratch.r0; + regs->sp = uregs.scratch.sp; + + return 0; +} + +static inline int is_do_ss_needed(unsigned int magic) +{ + if (MAGIC_SIGALTSTK == magic) + return 1; + else + return 0; +} + +SYSCALL_DEFINE0(rt_sigreturn) +{ + struct rt_sigframe __user *sf; + unsigned int magic; + struct pt_regs *regs = current_pt_regs(); + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + /* Since we stacked the signal on a word boundary, + * then 'sp' should be word aligned here. If it's + * not, then the user is trying to mess with us. + */ + if (regs->sp & 3) + goto badframe; + + sf = (struct rt_sigframe __force __user *)(regs->sp); + + if (!access_ok(sf, sizeof(*sf))) + goto badframe; + + if (__get_user(magic, &sf->sigret_magic)) + goto badframe; + + if (unlikely(is_do_ss_needed(magic))) + if (restore_altstack(&sf->uc.uc_stack)) + goto badframe; + + if (restore_usr_regs(regs, sf)) + goto badframe; + + /* Don't restart from sigreturn */ + syscall_wont_restart(regs); + + /* + * Ensure that sigreturn always returns to user mode (in case the + * regs saved on user stack got fudged between save and sigreturn) + * Otherwise it is easy to panic the kernel with a custom + * signal handler and/or restorer which clobberes the status32/ret + * to return to a bogus location in kernel mode. + */ + regs->status32 |= STATUS_U_MASK; + + return regs->r0; + +badframe: + force_sig(SIGSEGV); + return 0; +} + +/* + * Determine which stack to use.. + */ +static inline void __user *get_sigframe(struct ksignal *ksig, + struct pt_regs *regs, + unsigned long framesize) +{ + unsigned long sp = sigsp(regs->sp, ksig); + void __user *frame; + + /* No matter what happens, 'sp' must be word + * aligned otherwise nasty things could happen + */ + + /* ATPCS B01 mandates 8-byte alignment */ + frame = (void __user *)((sp - framesize) & ~7); + + /* Check that we can actually write to the signal frame */ + if (!access_ok(frame, framesize)) + frame = NULL; + + return frame; +} + +static int +setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) +{ + struct rt_sigframe __user *sf; + unsigned int magic = 0; + int err = 0; + + sf = get_sigframe(ksig, regs, sizeof(struct rt_sigframe)); + if (!sf) + return 1; + + /* + * w/o SA_SIGINFO, struct ucontext is partially populated (only + * uc_mcontext/uc_sigmask) for kernel's normal user state preservation + * during signal handler execution. This works for SA_SIGINFO as well + * although the semantics are now overloaded (the same reg state can be + * inspected by userland: but are they allowed to fiddle with it ? + */ + err |= stash_usr_regs(sf, regs, set); + + /* + * SA_SIGINFO requires 3 args to signal handler: + * #1: sig-no (common to any handler) + * #2: struct siginfo + * #3: struct ucontext (completely populated) + */ + if (unlikely(ksig->ka.sa.sa_flags & SA_SIGINFO)) { + err |= copy_siginfo_to_user(&sf->info, &ksig->info); + err |= __put_user(0, &sf->uc.uc_flags); + err |= __put_user(NULL, &sf->uc.uc_link); + err |= __save_altstack(&sf->uc.uc_stack, regs->sp); + + /* setup args 2 and 3 for user mode handler */ + regs->r1 = (unsigned long)&sf->info; + regs->r2 = (unsigned long)&sf->uc; + + /* + * small optim to avoid unconditonally calling do_sigaltstack + * in sigreturn path, now that we only have rt_sigreturn + */ + magic = MAGIC_SIGALTSTK; + } + + err |= __put_user(magic, &sf->sigret_magic); + if (err) + return err; + + /* #1 arg to the user Signal handler */ + regs->r0 = ksig->sig; + + /* setup PC of user space signal handler */ + regs->ret = (unsigned long)ksig->ka.sa.sa_handler; + + /* + * handler returns using sigreturn stub provided already by userpsace + * If not, nuke the process right away + */ + if(!(ksig->ka.sa.sa_flags & SA_RESTORER)) + return 1; + + regs->blink = (unsigned long)ksig->ka.sa.sa_restorer; + + /* User Stack for signal handler will be above the frame just carved */ + regs->sp = (unsigned long)sf; + + /* + * Bug 94183, Clear the DE bit, so that when signal handler + * starts to run, it doesn't use BTA + */ + regs->status32 &= ~STATUS_DE_MASK; + regs->status32 |= STATUS_L_MASK; + + return err; +} + +static void arc_restart_syscall(struct k_sigaction *ka, struct pt_regs *regs) +{ + switch (regs->r0) { + case -ERESTART_RESTARTBLOCK: + case -ERESTARTNOHAND: + /* + * ERESTARTNOHAND means that the syscall should + * only be restarted if there was no handler for + * the signal, and since we only get here if there + * is a handler, we don't restart + */ + regs->r0 = -EINTR; /* ERESTART_xxx is internal */ + break; + + case -ERESTARTSYS: + /* + * ERESTARTSYS means to restart the syscall if + * there is no handler or the handler was + * registered with SA_RESTART + */ + if (!(ka->sa.sa_flags & SA_RESTART)) { + regs->r0 = -EINTR; + break; + } + fallthrough; + + case -ERESTARTNOINTR: + /* + * ERESTARTNOINTR means that the syscall should + * be called again after the signal handler returns. + * Setup reg state just as it was before doing the trap + * r0 has been clobbered with sys call ret code thus it + * needs to be reloaded with orig first arg to syscall + * in orig_r0. Rest of relevant reg-file: + * r8 (syscall num) and (r1 - r7) will be reset to + * their orig user space value when we ret from kernel + */ + regs->r0 = regs->orig_r0; + regs->ret -= is_isa_arcv2() ? 2 : 4; + break; + } +} + +/* + * OK, we're invoking a handler + */ +static void +handle_signal(struct ksignal *ksig, struct pt_regs *regs) +{ + sigset_t *oldset = sigmask_to_save(); + int failed; + + /* Set up the stack frame */ + failed = setup_rt_frame(ksig, oldset, regs); + + signal_setup_done(failed, ksig, 0); +} + +void do_signal(struct pt_regs *regs) +{ + struct ksignal ksig; + int restart_scall; + + restart_scall = in_syscall(regs) && syscall_restartable(regs); + + if (test_thread_flag(TIF_SIGPENDING) && get_signal(&ksig)) { + if (restart_scall) { + arc_restart_syscall(&ksig.ka, regs); + syscall_wont_restart(regs); /* No more restarts */ + } + handle_signal(&ksig, regs); + return; + } + + if (restart_scall) { + /* No handler for syscall: restart it */ + if (regs->r0 == -ERESTARTNOHAND || + regs->r0 == -ERESTARTSYS || regs->r0 == -ERESTARTNOINTR) { + regs->r0 = regs->orig_r0; + regs->ret -= is_isa_arcv2() ? 2 : 4; + } else if (regs->r0 == -ERESTART_RESTARTBLOCK) { + regs->r8 = __NR_restart_syscall; + regs->ret -= is_isa_arcv2() ? 2 : 4; + } + syscall_wont_restart(regs); /* No more restarts */ + } + + /* If there's no signal to deliver, restore the saved sigmask back */ + restore_saved_sigmask(); +} + +void do_notify_resume(struct pt_regs *regs) +{ + /* + * ASM glue gaurantees that this is only called when returning to + * user mode + */ + if (test_thread_flag(TIF_NOTIFY_RESUME)) + tracehook_notify_resume(regs); +} diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c new file mode 100644 index 000000000..db0e104d6 --- /dev/null +++ b/arch/arc/kernel/smp.c @@ -0,0 +1,423 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * RajeshwarR: Dec 11, 2007 + * -- Added support for Inter Processor Interrupts + * + * Vineetg: Nov 1st, 2007 + * -- Initial Write (Borrowed heavily from ARM) + */ + +#include <linux/spinlock.h> +#include <linux/sched/mm.h> +#include <linux/interrupt.h> +#include <linux/profile.h> +#include <linux/mm.h> +#include <linux/cpu.h> +#include <linux/irq.h> +#include <linux/atomic.h> +#include <linux/cpumask.h> +#include <linux/reboot.h> +#include <linux/irqdomain.h> +#include <linux/export.h> +#include <linux/of_fdt.h> + +#include <asm/processor.h> +#include <asm/setup.h> +#include <asm/mach_desc.h> + +#ifndef CONFIG_ARC_HAS_LLSC +arch_spinlock_t smp_atomic_ops_lock = __ARCH_SPIN_LOCK_UNLOCKED; +arch_spinlock_t smp_bitops_lock = __ARCH_SPIN_LOCK_UNLOCKED; + +EXPORT_SYMBOL_GPL(smp_atomic_ops_lock); +EXPORT_SYMBOL_GPL(smp_bitops_lock); +#endif + +struct plat_smp_ops __weak plat_smp_ops; + +/* XXX: per cpu ? Only needed once in early seconday boot */ +struct task_struct *secondary_idle_tsk; + +/* Called from start_kernel */ +void __init smp_prepare_boot_cpu(void) +{ +} + +static int __init arc_get_cpu_map(const char *name, struct cpumask *cpumask) +{ + unsigned long dt_root = of_get_flat_dt_root(); + const char *buf; + + buf = of_get_flat_dt_prop(dt_root, name, NULL); + if (!buf) + return -EINVAL; + + if (cpulist_parse(buf, cpumask)) + return -EINVAL; + + return 0; +} + +/* + * Read from DeviceTree and setup cpu possible mask. If there is no + * "possible-cpus" property in DeviceTree pretend all [0..NR_CPUS-1] exist. + */ +static void __init arc_init_cpu_possible(void) +{ + struct cpumask cpumask; + + if (arc_get_cpu_map("possible-cpus", &cpumask)) { + pr_warn("Failed to get possible-cpus from dtb, pretending all %u cpus exist\n", + NR_CPUS); + + cpumask_setall(&cpumask); + } + + if (!cpumask_test_cpu(0, &cpumask)) + panic("Master cpu (cpu[0]) is missed in cpu possible mask!"); + + init_cpu_possible(&cpumask); +} + +/* + * Called from setup_arch() before calling setup_processor() + * + * - Initialise the CPU possible map early - this describes the CPUs + * which may be present or become present in the system. + * - Call early smp init hook. This can initialize a specific multi-core + * IP which is say common to several platforms (hence not part of + * platform specific int_early() hook) + */ +void __init smp_init_cpus(void) +{ + arc_init_cpu_possible(); + + if (plat_smp_ops.init_early_smp) + plat_smp_ops.init_early_smp(); +} + +/* called from init ( ) => process 1 */ +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + /* + * if platform didn't set the present map already, do it now + * boot cpu is set to present already by init/main.c + */ + if (num_present_cpus() <= 1) + init_cpu_present(cpu_possible_mask); +} + +void __init smp_cpus_done(unsigned int max_cpus) +{ + +} + +/* + * Default smp boot helper for Run-on-reset case where all cores start off + * together. Non-masters need to wait for Master to start running. + * This is implemented using a flag in memory, which Non-masters spin-wait on. + * Master sets it to cpu-id of core to "ungate" it. + */ +static volatile int wake_flag; + +#ifdef CONFIG_ISA_ARCOMPACT + +#define __boot_read(f) f +#define __boot_write(f, v) f = v + +#else + +#define __boot_read(f) arc_read_uncached_32(&f) +#define __boot_write(f, v) arc_write_uncached_32(&f, v) + +#endif + +static void arc_default_smp_cpu_kick(int cpu, unsigned long pc) +{ + BUG_ON(cpu == 0); + + __boot_write(wake_flag, cpu); +} + +void arc_platform_smp_wait_to_boot(int cpu) +{ + /* for halt-on-reset, we've waited already */ + if (IS_ENABLED(CONFIG_ARC_SMP_HALT_ON_RESET)) + return; + + while (__boot_read(wake_flag) != cpu) + ; + + __boot_write(wake_flag, 0); +} + +const char *arc_platform_smp_cpuinfo(void) +{ + return plat_smp_ops.info ? : ""; +} + +/* + * The very first "C" code executed by secondary + * Called from asm stub in head.S + * "current"/R25 already setup by low level boot code + */ +void start_kernel_secondary(void) +{ + struct mm_struct *mm = &init_mm; + unsigned int cpu = smp_processor_id(); + + /* MMU, Caches, Vector Table, Interrupts etc */ + setup_processor(); + + mmget(mm); + mmgrab(mm); + current->active_mm = mm; + cpumask_set_cpu(cpu, mm_cpumask(mm)); + + /* Some SMP H/w setup - for each cpu */ + if (plat_smp_ops.init_per_cpu) + plat_smp_ops.init_per_cpu(cpu); + + if (machine_desc->init_per_cpu) + machine_desc->init_per_cpu(cpu); + + notify_cpu_starting(cpu); + set_cpu_online(cpu, true); + + pr_info("## CPU%u LIVE ##: Executing Code...\n", cpu); + + local_irq_enable(); + cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); +} + +/* + * Called from kernel_init( ) -> smp_init( ) - for each CPU + * + * At this point, Secondary Processor is "HALT"ed: + * -It booted, but was halted in head.S + * -It was configured to halt-on-reset + * So need to wake it up. + * + * Essential requirements being where to run from (PC) and stack (SP) +*/ +int __cpu_up(unsigned int cpu, struct task_struct *idle) +{ + unsigned long wait_till; + + secondary_idle_tsk = idle; + + pr_info("Idle Task [%d] %p", cpu, idle); + pr_info("Trying to bring up CPU%u ...\n", cpu); + + if (plat_smp_ops.cpu_kick) + plat_smp_ops.cpu_kick(cpu, + (unsigned long)first_lines_of_secondary); + else + arc_default_smp_cpu_kick(cpu, (unsigned long)NULL); + + /* wait for 1 sec after kicking the secondary */ + wait_till = jiffies + HZ; + while (time_before(jiffies, wait_till)) { + if (cpu_online(cpu)) + break; + } + + if (!cpu_online(cpu)) { + pr_info("Timeout: CPU%u FAILED to come up !!!\n", cpu); + return -1; + } + + secondary_idle_tsk = NULL; + + return 0; +} + +/* + * not supported here + */ +int setup_profiling_timer(unsigned int multiplier) +{ + return -EINVAL; +} + +/*****************************************************************************/ +/* Inter Processor Interrupt Handling */ +/*****************************************************************************/ + +enum ipi_msg_type { + IPI_EMPTY = 0, + IPI_RESCHEDULE = 1, + IPI_CALL_FUNC, + IPI_CPU_STOP, +}; + +/* + * In arches with IRQ for each msg type (above), receiver can use IRQ-id to + * figure out what msg was sent. For those which don't (ARC has dedicated IPI + * IRQ), the msg-type needs to be conveyed via per-cpu data + */ + +static DEFINE_PER_CPU(unsigned long, ipi_data); + +static void ipi_send_msg_one(int cpu, enum ipi_msg_type msg) +{ + unsigned long __percpu *ipi_data_ptr = per_cpu_ptr(&ipi_data, cpu); + unsigned long old, new; + unsigned long flags; + + pr_debug("%d Sending msg [%d] to %d\n", smp_processor_id(), msg, cpu); + + local_irq_save(flags); + + /* + * Atomically write new msg bit (in case others are writing too), + * and read back old value + */ + do { + new = old = READ_ONCE(*ipi_data_ptr); + new |= 1U << msg; + } while (cmpxchg(ipi_data_ptr, old, new) != old); + + /* + * Call the platform specific IPI kick function, but avoid if possible: + * Only do so if there's no pending msg from other concurrent sender(s). + * Otherwise, recevier will see this msg as well when it takes the + * IPI corresponding to that msg. This is true, even if it is already in + * IPI handler, because !@old means it has not yet dequeued the msg(s) + * so @new msg can be a free-loader + */ + if (plat_smp_ops.ipi_send && !old) + plat_smp_ops.ipi_send(cpu); + + local_irq_restore(flags); +} + +static void ipi_send_msg(const struct cpumask *callmap, enum ipi_msg_type msg) +{ + unsigned int cpu; + + for_each_cpu(cpu, callmap) + ipi_send_msg_one(cpu, msg); +} + +void smp_send_reschedule(int cpu) +{ + ipi_send_msg_one(cpu, IPI_RESCHEDULE); +} + +void smp_send_stop(void) +{ + struct cpumask targets; + cpumask_copy(&targets, cpu_online_mask); + cpumask_clear_cpu(smp_processor_id(), &targets); + ipi_send_msg(&targets, IPI_CPU_STOP); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + ipi_send_msg_one(cpu, IPI_CALL_FUNC); +} + +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + ipi_send_msg(mask, IPI_CALL_FUNC); +} + +/* + * ipi_cpu_stop - handle IPI from smp_send_stop() + */ +static void ipi_cpu_stop(void) +{ + machine_halt(); +} + +static inline int __do_IPI(unsigned long msg) +{ + int rc = 0; + + switch (msg) { + case IPI_RESCHEDULE: + scheduler_ipi(); + break; + + case IPI_CALL_FUNC: + generic_smp_call_function_interrupt(); + break; + + case IPI_CPU_STOP: + ipi_cpu_stop(); + break; + + default: + rc = 1; + } + + return rc; +} + +/* + * arch-common ISR to handle for inter-processor interrupts + * Has hooks for platform specific IPI + */ +irqreturn_t do_IPI(int irq, void *dev_id) +{ + unsigned long pending; + unsigned long __maybe_unused copy; + + pr_debug("IPI [%ld] received on cpu %d\n", + *this_cpu_ptr(&ipi_data), smp_processor_id()); + + if (plat_smp_ops.ipi_clear) + plat_smp_ops.ipi_clear(irq); + + /* + * "dequeue" the msg corresponding to this IPI (and possibly other + * piggybacked msg from elided IPIs: see ipi_send_msg_one() above) + */ + copy = pending = xchg(this_cpu_ptr(&ipi_data), 0); + + do { + unsigned long msg = __ffs(pending); + int rc; + + rc = __do_IPI(msg); + if (rc) + pr_info("IPI with bogus msg %ld in %ld\n", msg, copy); + pending &= ~(1U << msg); + } while (pending); + + return IRQ_HANDLED; +} + +/* + * API called by platform code to hookup arch-common ISR to their IPI IRQ + * + * Note: If IPI is provided by platform (vs. say ARC MCIP), their intc setup/map + * function needs to call call irq_set_percpu_devid() for IPI IRQ, otherwise + * request_percpu_irq() below will fail + */ +static DEFINE_PER_CPU(int, ipi_dev); + +int smp_ipi_irq_setup(int cpu, irq_hw_number_t hwirq) +{ + int *dev = per_cpu_ptr(&ipi_dev, cpu); + unsigned int virq = irq_find_mapping(NULL, hwirq); + + if (!virq) + panic("Cannot find virq for root domain and hwirq=%lu", hwirq); + + /* Boot cpu calls request, all call enable */ + if (!cpu) { + int rc; + + rc = request_percpu_irq(virq, do_IPI, "IPI Interrupt", dev); + if (rc) + panic("Percpu IRQ request failed for %u\n", virq); + } + + enable_percpu_irq(virq, 0); + + return 0; +} diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c new file mode 100644 index 000000000..f73da203b --- /dev/null +++ b/arch/arc/kernel/stacktrace.c @@ -0,0 +1,274 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * stacktrace.c : stacktracing APIs needed by rest of kernel + * (wrappers over ARC dwarf based unwinder) + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * vineetg: aug 2009 + * -Implemented CONFIG_STACKTRACE APIs, primarily save_stack_trace_tsk( ) + * for displaying task's kernel mode call stack in /proc/<pid>/stack + * -Iterator based approach to have single copy of unwinding core and APIs + * needing unwinding, implement the logic in iterator regarding: + * = which frame onwards to start capture + * = which frame to stop capturing (wchan) + * = specifics of data structs where trace is saved(CONFIG_STACKTRACE etc) + * + * vineetg: March 2009 + * -Implemented correct versions of thread_saved_pc() and get_wchan() + * + * rajeshwarr: 2008 + * -Initial implementation + */ + +#include <linux/ptrace.h> +#include <linux/export.h> +#include <linux/stacktrace.h> +#include <linux/kallsyms.h> +#include <linux/sched/debug.h> + +#include <asm/arcregs.h> +#include <asm/unwind.h> +#include <asm/switch_to.h> + +/*------------------------------------------------------------------------- + * Unwinder Iterator + *------------------------------------------------------------------------- + */ + +#ifdef CONFIG_ARC_DW2_UNWIND + +static int +seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs, + struct unwind_frame_info *frame_info) +{ + if (regs) { + /* + * Asynchronous unwinding of intr/exception + * - Just uses the pt_regs passed + */ + frame_info->task = tsk; + + frame_info->regs.r27 = regs->fp; + frame_info->regs.r28 = regs->sp; + frame_info->regs.r31 = regs->blink; + frame_info->regs.r63 = regs->ret; + frame_info->call_frame = 0; + } else if (tsk == NULL || tsk == current) { + /* + * synchronous unwinding (e.g. dump_stack) + * - uses current values of SP and friends + */ + unsigned long fp, sp, blink, ret; + frame_info->task = current; + + __asm__ __volatile__( + "mov %0,r27\n\t" + "mov %1,r28\n\t" + "mov %2,r31\n\t" + "mov %3,r63\n\t" + : "=r"(fp), "=r"(sp), "=r"(blink), "=r"(ret) + ); + + frame_info->regs.r27 = fp; + frame_info->regs.r28 = sp; + frame_info->regs.r31 = blink; + frame_info->regs.r63 = ret; + frame_info->call_frame = 0; + } else { + /* + * Asynchronous unwinding of a likely sleeping task + * - first ensure it is actually sleeping + * - if so, it will be in __switch_to, kernel mode SP of task + * is safe-kept and BLINK at a well known location in there + */ + + if (tsk->state == TASK_RUNNING) + return -1; + + frame_info->task = tsk; + + frame_info->regs.r27 = TSK_K_FP(tsk); + frame_info->regs.r28 = TSK_K_ESP(tsk); + frame_info->regs.r31 = TSK_K_BLINK(tsk); + frame_info->regs.r63 = (unsigned int)__switch_to; + + /* In the prologue of __switch_to, first FP is saved on stack + * and then SP is copied to FP. Dwarf assumes cfa as FP based + * but we didn't save FP. The value retrieved above is FP's + * state in previous frame. + * As a work around for this, we unwind from __switch_to start + * and adjust SP accordingly. The other limitation is that + * __switch_to macro is dwarf rules are not generated for inline + * assembly code + */ + frame_info->regs.r27 = 0; + frame_info->regs.r28 += 60; + frame_info->call_frame = 0; + + } + return 0; +} + +#endif + +notrace noinline unsigned int +arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs, + int (*consumer_fn) (unsigned int, void *), void *arg) +{ +#ifdef CONFIG_ARC_DW2_UNWIND + int ret = 0, cnt = 0; + unsigned int address; + struct unwind_frame_info frame_info; + + if (seed_unwind_frame_info(tsk, regs, &frame_info)) + return 0; + + while (1) { + address = UNW_PC(&frame_info); + + if (!address || !__kernel_text_address(address)) + break; + + if (consumer_fn(address, arg) == -1) + break; + + ret = arc_unwind(&frame_info); + if (ret) + break; + + frame_info.regs.r63 = frame_info.regs.r31; + + if (cnt++ > 128) { + printk("unwinder looping too long, aborting !\n"); + return 0; + } + } + + return address; /* return the last address it saw */ +#else + /* On ARC, only Dward based unwinder works. fp based backtracing is + * not possible (-fno-omit-frame-pointer) because of the way function + * prelogue is setup (callee regs saved and then fp set and not other + * way around + */ + pr_warn_once("CONFIG_ARC_DW2_UNWIND needs to be enabled\n"); + return 0; + +#endif +} + +/*------------------------------------------------------------------------- + * callbacks called by unwinder iterator to implement kernel APIs + * + * The callback can return -1 to force the iterator to stop, which by default + * keeps going till the bottom-most frame. + *------------------------------------------------------------------------- + */ + +/* Call-back which plugs into unwinding core to dump the stack in + * case of panic/OOPs/BUG etc + */ +static int __print_sym(unsigned int address, void *arg) +{ + const char *loglvl = arg; + + printk("%s %pS\n", loglvl, (void *)address); + return 0; +} + +#ifdef CONFIG_STACKTRACE + +/* Call-back which plugs into unwinding core to capture the + * traces needed by kernel on /proc/<pid>/stack + */ +static int __collect_all(unsigned int address, void *arg) +{ + struct stack_trace *trace = arg; + + if (trace->skip > 0) + trace->skip--; + else + trace->entries[trace->nr_entries++] = address; + + if (trace->nr_entries >= trace->max_entries) + return -1; + + return 0; +} + +static int __collect_all_but_sched(unsigned int address, void *arg) +{ + struct stack_trace *trace = arg; + + if (in_sched_functions(address)) + return 0; + + if (trace->skip > 0) + trace->skip--; + else + trace->entries[trace->nr_entries++] = address; + + if (trace->nr_entries >= trace->max_entries) + return -1; + + return 0; +} + +#endif + +static int __get_first_nonsched(unsigned int address, void *unused) +{ + if (in_sched_functions(address)) + return 0; + + return -1; +} + +/*------------------------------------------------------------------------- + * APIs expected by various kernel sub-systems + *------------------------------------------------------------------------- + */ + +noinline void show_stacktrace(struct task_struct *tsk, struct pt_regs *regs, + const char *loglvl) +{ + printk("%s\nStack Trace:\n", loglvl); + arc_unwind_core(tsk, regs, __print_sym, (void *)loglvl); +} +EXPORT_SYMBOL(show_stacktrace); + +/* Expected by sched Code */ +void show_stack(struct task_struct *tsk, unsigned long *sp, const char *loglvl) +{ + show_stacktrace(tsk, NULL, loglvl); +} + +/* Another API expected by schedular, shows up in "ps" as Wait Channel + * Of course just returning schedule( ) would be pointless so unwind until + * the function is not in schedular code + */ +unsigned int get_wchan(struct task_struct *tsk) +{ + return arc_unwind_core(tsk, NULL, __get_first_nonsched, NULL); +} + +#ifdef CONFIG_STACKTRACE + +/* + * API required by CONFIG_STACKTRACE, CONFIG_LATENCYTOP. + * A typical use is when /proc/<pid>/stack is queried by userland + */ +void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) +{ + /* Assumes @tsk is sleeping so unwinds from __switch_to */ + arc_unwind_core(tsk, NULL, __collect_all_but_sched, trace); +} + +void save_stack_trace(struct stack_trace *trace) +{ + /* Pass NULL for task so it unwinds the current call frame */ + arc_unwind_core(NULL, NULL, __collect_all, trace); +} +EXPORT_SYMBOL_GPL(save_stack_trace); +#endif diff --git a/arch/arc/kernel/sys.c b/arch/arc/kernel/sys.c new file mode 100644 index 000000000..1069446bd --- /dev/null +++ b/arch/arc/kernel/sys.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/syscalls.h> +#include <linux/signal.h> +#include <linux/unistd.h> + +#include <asm/syscalls.h> + +#define sys_clone sys_clone_wrapper +#define sys_clone3 sys_clone3_wrapper + +#undef __SYSCALL +#define __SYSCALL(nr, call) [nr] = (call), + +void *sys_call_table[NR_syscalls] = { + [0 ... NR_syscalls-1] = sys_ni_syscall, +#include <asm/unistd.h> +}; diff --git a/arch/arc/kernel/traps.c b/arch/arc/kernel/traps.c new file mode 100644 index 000000000..57235e5c0 --- /dev/null +++ b/arch/arc/kernel/traps.c @@ -0,0 +1,164 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Traps/Non-MMU Exception handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * vineetg: May 2011 + * -user-space unaligned access emulation + * + * Rahul Trivedi: Codito Technologies 2004 + */ + +#include <linux/sched/signal.h> +#include <linux/kdebug.h> +#include <linux/uaccess.h> +#include <linux/ptrace.h> +#include <linux/kprobes.h> +#include <linux/kgdb.h> +#include <asm/setup.h> +#include <asm/unaligned.h> +#include <asm/kprobes.h> + +void __init trap_init(void) +{ + return; +} + +void die(const char *str, struct pt_regs *regs, unsigned long address) +{ + show_kernel_fault_diag(str, regs, address); + + /* DEAD END */ + __asm__("flag 1"); +} + +/* + * Helper called for bulk of exceptions NOT needing specific handling + * -for user faults enqueues requested signal + * -for kernel, chk if due to copy_(to|from)_user, otherwise die() + */ +static noinline int +unhandled_exception(const char *str, struct pt_regs *regs, + int signo, int si_code, void __user *addr) +{ + if (user_mode(regs)) { + struct task_struct *tsk = current; + + tsk->thread.fault_address = (__force unsigned int)addr; + + force_sig_fault(signo, si_code, addr); + + } else { + /* If not due to copy_(to|from)_user, we are doomed */ + if (fixup_exception(regs)) + return 0; + + die(str, regs, (unsigned long)addr); + } + + return 1; +} + +#define DO_ERROR_INFO(signr, str, name, sicode) \ +int name(unsigned long address, struct pt_regs *regs) \ +{ \ + return unhandled_exception(str, regs, signr, sicode, \ + (void __user *)address); \ +} + +/* + * Entry points for exceptions NOT needing specific handling + */ +DO_ERROR_INFO(SIGILL, "Priv Op/Disabled Extn", do_privilege_fault, ILL_PRVOPC) +DO_ERROR_INFO(SIGILL, "Invalid Extn Insn", do_extension_fault, ILL_ILLOPC) +DO_ERROR_INFO(SIGILL, "Illegal Insn (or Seq)", insterror_is_error, ILL_ILLOPC) +DO_ERROR_INFO(SIGBUS, "Invalid Mem Access", __weak do_memory_error, BUS_ADRERR) +DO_ERROR_INFO(SIGTRAP, "Breakpoint Set", trap_is_brkpt, TRAP_BRKPT) +DO_ERROR_INFO(SIGBUS, "Misaligned Access", do_misaligned_error, BUS_ADRALN) +DO_ERROR_INFO(SIGSEGV, "gcc generated __builtin_trap", do_trap5_error, 0) + +/* + * Entry Point for Misaligned Data access Exception, for emulating in software + */ +int do_misaligned_access(unsigned long address, struct pt_regs *regs, + struct callee_regs *cregs) +{ + /* If emulation not enabled, or failed, kill the task */ + if (misaligned_fixup(address, regs, cregs) != 0) + return do_misaligned_error(address, regs); + + return 0; +} + +/* + * Entry point for miscll errors such as Nested Exceptions + * -Duplicate TLB entry is handled seperately though + */ +void do_machine_check_fault(unsigned long address, struct pt_regs *regs) +{ + die("Unhandled Machine Check Exception", regs, address); +} + + +/* + * Entry point for traps induced by ARCompact TRAP_S <n> insn + * This is same family as TRAP0/SWI insn (use the same vector). + * The only difference being SWI insn take no operand, while TRAP_S does + * which reflects in ECR Reg as 8 bit param. + * Thus TRAP_S <n> can be used for specific purpose + * -1 used for software breakpointing (gdb) + * -2 used by kprobes + * -5 __builtin_trap() generated by gcc (2018.03 onwards) for toggle such as + * -fno-isolate-erroneous-paths-dereference + */ +void do_non_swi_trap(unsigned long address, struct pt_regs *regs) +{ + unsigned int param = regs->ecr_param; + + switch (param) { + case 1: + trap_is_brkpt(address, regs); + break; + + case 2: + trap_is_kprobe(address, regs); + break; + + case 3: + case 4: + kgdb_trap(regs); + break; + + case 5: + do_trap5_error(address, regs); + break; + default: + break; + } +} + +/* + * Entry point for Instruction Error Exception + * -For a corner case, ARC kprobes implementation resorts to using + * this exception, hence the check + */ +void do_insterror_or_kprobe(unsigned long address, struct pt_regs *regs) +{ + int rc; + + /* Check if this exception is caused by kprobes */ + rc = notify_die(DIE_IERR, "kprobe_ierr", regs, address, 0, SIGILL); + if (rc == NOTIFY_STOP) + return; + + insterror_is_error(address, regs); +} + +/* + * abort() call generated by older gcc for __builtin_trap() + */ +void abort(void) +{ + __asm__ __volatile__("trap_s 5\n"); +} diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c new file mode 100644 index 000000000..a331bb5d8 --- /dev/null +++ b/arch/arc/kernel/troubleshoot.c @@ -0,0 +1,227 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/ptrace.h> +#include <linux/module.h> +#include <linux/mm.h> +#include <linux/fs.h> +#include <linux/kdev_t.h> +#include <linux/proc_fs.h> +#include <linux/file.h> +#include <linux/sched/mm.h> +#include <linux/sched/debug.h> + +#include <asm/arcregs.h> +#include <asm/irqflags.h> + +#define ARC_PATH_MAX 256 + +static noinline void print_regs_scratch(struct pt_regs *regs) +{ + pr_cont("BTA: 0x%08lx\n SP: 0x%08lx FP: 0x%08lx BLK: %pS\n", + regs->bta, regs->sp, regs->fp, (void *)regs->blink); + pr_cont("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n", + regs->lp_start, regs->lp_end, regs->lp_count); + + pr_info("r00: 0x%08lx\tr01: 0x%08lx\tr02: 0x%08lx\n" \ + "r03: 0x%08lx\tr04: 0x%08lx\tr05: 0x%08lx\n" \ + "r06: 0x%08lx\tr07: 0x%08lx\tr08: 0x%08lx\n" \ + "r09: 0x%08lx\tr10: 0x%08lx\tr11: 0x%08lx\n" \ + "r12: 0x%08lx\t", + regs->r0, regs->r1, regs->r2, + regs->r3, regs->r4, regs->r5, + regs->r6, regs->r7, regs->r8, + regs->r9, regs->r10, regs->r11, + regs->r12); +} + +static void print_regs_callee(struct callee_regs *regs) +{ + pr_cont("r13: 0x%08lx\tr14: 0x%08lx\n" \ + "r15: 0x%08lx\tr16: 0x%08lx\tr17: 0x%08lx\n" \ + "r18: 0x%08lx\tr19: 0x%08lx\tr20: 0x%08lx\n" \ + "r21: 0x%08lx\tr22: 0x%08lx\tr23: 0x%08lx\n" \ + "r24: 0x%08lx\tr25: 0x%08lx\n", + regs->r13, regs->r14, + regs->r15, regs->r16, regs->r17, + regs->r18, regs->r19, regs->r20, + regs->r21, regs->r22, regs->r23, + regs->r24, regs->r25); +} + +static void print_task_path_n_nm(struct task_struct *tsk) +{ + char *path_nm = NULL; + struct mm_struct *mm; + struct file *exe_file; + char buf[ARC_PATH_MAX]; + + mm = get_task_mm(tsk); + if (!mm) + goto done; + + exe_file = get_mm_exe_file(mm); + mmput(mm); + + if (exe_file) { + path_nm = file_path(exe_file, buf, ARC_PATH_MAX-1); + fput(exe_file); + } + +done: + pr_info("Path: %s\n", !IS_ERR(path_nm) ? path_nm : "?"); +} + +static void show_faulting_vma(unsigned long address) +{ + struct vm_area_struct *vma; + struct mm_struct *active_mm = current->active_mm; + + /* can't use print_vma_addr() yet as it doesn't check for + * non-inclusive vma + */ + mmap_read_lock(active_mm); + vma = find_vma(active_mm, address); + + /* check against the find_vma( ) behaviour which returns the next VMA + * if the container VMA is not found + */ + if (vma && (vma->vm_start <= address)) { + char buf[ARC_PATH_MAX]; + char *nm = "?"; + + if (vma->vm_file) { + nm = file_path(vma->vm_file, buf, ARC_PATH_MAX-1); + if (IS_ERR(nm)) + nm = "?"; + } + pr_info(" @off 0x%lx in [%s] VMA: 0x%08lx to 0x%08lx\n", + vma->vm_start < TASK_UNMAPPED_BASE ? + address : address - vma->vm_start, + nm, vma->vm_start, vma->vm_end); + } else + pr_info(" @No matching VMA found\n"); + + mmap_read_unlock(active_mm); +} + +static void show_ecr_verbose(struct pt_regs *regs) +{ + unsigned int vec, cause_code; + unsigned long address; + + /* For Data fault, this is data address not instruction addr */ + address = current->thread.fault_address; + + vec = regs->ecr_vec; + cause_code = regs->ecr_cause; + + /* For DTLB Miss or ProtV, display the memory involved too */ + if (vec == ECR_V_DTLB_MISS) { + pr_cont("Invalid %s @ 0x%08lx by insn @ %pS\n", + (cause_code == 0x01) ? "Read" : + ((cause_code == 0x02) ? "Write" : "EX"), + address, (void *)regs->ret); + } else if (vec == ECR_V_ITLB_MISS) { + pr_cont("Insn could not be fetched\n"); + } else if (vec == ECR_V_MACH_CHK) { + pr_cont("Machine Check (%s)\n", (cause_code == 0x0) ? + "Double Fault" : "Other Fatal Err"); + + } else if (vec == ECR_V_PROTV) { + if (cause_code == ECR_C_PROTV_INST_FETCH) + pr_cont("Execute from Non-exec Page\n"); + else if (cause_code == ECR_C_PROTV_MISALIG_DATA && + IS_ENABLED(CONFIG_ISA_ARCOMPACT)) + pr_cont("Misaligned r/w from 0x%08lx\n", address); + else + pr_cont("%s access not allowed on page\n", + (cause_code == 0x01) ? "Read" : + ((cause_code == 0x02) ? "Write" : "EX")); + } else if (vec == ECR_V_INSN_ERR) { + pr_cont("Illegal Insn\n"); +#ifdef CONFIG_ISA_ARCV2 + } else if (vec == ECR_V_MEM_ERR) { + if (cause_code == 0x00) + pr_cont("Bus Error from Insn Mem\n"); + else if (cause_code == 0x10) + pr_cont("Bus Error from Data Mem\n"); + else + pr_cont("Bus Error, check PRM\n"); + } else if (vec == ECR_V_MISALIGN) { + pr_cont("Misaligned r/w from 0x%08lx\n", address); +#endif + } else if (vec == ECR_V_TRAP) { + if (regs->ecr_param == 5) + pr_cont("gcc generated __builtin_trap\n"); + } else { + pr_cont("Check Programmer's Manual\n"); + } +} + +/************************************************************************ + * API called by rest of kernel + ***********************************************************************/ + +void show_regs(struct pt_regs *regs) +{ + struct task_struct *tsk = current; + struct callee_regs *cregs = (struct callee_regs *)tsk->thread.callee_reg; + + /* + * generic code calls us with preemption disabled, but some calls + * here could sleep, so re-enable to avoid lockdep splat + */ + preempt_enable(); + + print_task_path_n_nm(tsk); + show_regs_print_info(KERN_INFO); + + show_ecr_verbose(regs); + + if (user_mode(regs)) + show_faulting_vma(regs->ret); /* faulting code, not data */ + + pr_info("ECR: 0x%08lx EFA: 0x%08lx ERET: 0x%08lx\nSTAT: 0x%08lx", + regs->event, current->thread.fault_address, regs->ret, + regs->status32); + +#define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit" " : "" + +#ifdef CONFIG_ISA_ARCOMPACT + pr_cont(" [%2s%2s%2s%2s%2s%2s%2s]", + (regs->status32 & STATUS_U_MASK) ? "U " : "K ", + STS_BIT(regs, DE), STS_BIT(regs, AE), + STS_BIT(regs, A2), STS_BIT(regs, A1), + STS_BIT(regs, E2), STS_BIT(regs, E1)); +#else + pr_cont(" [%2s%2s%2s%2s] ", + STS_BIT(regs, IE), + (regs->status32 & STATUS_U_MASK) ? "U " : "K ", + STS_BIT(regs, DE), STS_BIT(regs, AE)); +#endif + + print_regs_scratch(regs); + if (cregs) + print_regs_callee(cregs); + + preempt_disable(); +} + +void show_kernel_fault_diag(const char *str, struct pt_regs *regs, + unsigned long address) +{ + current->thread.fault_address = address; + + /* Show fault description */ + pr_info("\n%s\n", str); + + /* Caller and Callee regs */ + show_regs(regs); + + /* Show stack trace if this Fatality happened in kernel mode */ + if (!user_mode(regs)) + show_stacktrace(current, regs, KERN_DEFAULT); +} diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c new file mode 100644 index 000000000..d63ebd81f --- /dev/null +++ b/arch/arc/kernel/unaligned.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2011-2012 Synopsys (www.synopsys.com) + * + * vineetg : May 2011 + * -Adapted (from .26 to .35) + * -original contribution by Tim.yao@amlogic.com + */ + +#include <linux/types.h> +#include <linux/perf_event.h> +#include <linux/ptrace.h> +#include <linux/uaccess.h> +#include <asm/disasm.h> + +#ifdef CONFIG_CPU_BIG_ENDIAN +#define BE 1 +#define FIRST_BYTE_16 "swap %1, %1\n swape %1, %1\n" +#define FIRST_BYTE_32 "swape %1, %1\n" +#else +#define BE 0 +#define FIRST_BYTE_16 +#define FIRST_BYTE_32 +#endif + +#define __get8_unaligned_check(val, addr, err) \ + __asm__( \ + "1: ldb.ab %1, [%2, 1]\n" \ + "2:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "3: mov %0, 1\n" \ + " j 2b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b, 3b\n" \ + " .previous\n" \ + : "=r" (err), "=&r" (val), "=r" (addr) \ + : "0" (err), "2" (addr)) + +#define get16_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v, a = addr; \ + __get8_unaligned_check(v, a, err); \ + val = v << ((BE) ? 8 : 0); \ + __get8_unaligned_check(v, a, err); \ + val |= v << ((BE) ? 0 : 8); \ + if (err) \ + goto fault; \ + } while (0) + +#define get32_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v, a = addr; \ + __get8_unaligned_check(v, a, err); \ + val = v << ((BE) ? 24 : 0); \ + __get8_unaligned_check(v, a, err); \ + val |= v << ((BE) ? 16 : 8); \ + __get8_unaligned_check(v, a, err); \ + val |= v << ((BE) ? 8 : 16); \ + __get8_unaligned_check(v, a, err); \ + val |= v << ((BE) ? 0 : 24); \ + if (err) \ + goto fault; \ + } while (0) + +#define put16_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v = val, a = addr;\ + \ + __asm__( \ + FIRST_BYTE_16 \ + "1: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "2: stb %1, [%2]\n" \ + "3:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "4: mov %0, 1\n" \ + " j 3b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b, 4b\n" \ + " .long 2b, 4b\n" \ + " .previous\n" \ + : "=r" (err), "=&r" (v), "=&r" (a) \ + : "0" (err), "1" (v), "2" (a)); \ + \ + if (err) \ + goto fault; \ + } while (0) + +#define put32_unaligned_check(val, addr) \ + do { \ + unsigned int err = 0, v = val, a = addr;\ + \ + __asm__( \ + FIRST_BYTE_32 \ + "1: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "2: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "3: stb.ab %1, [%2, 1]\n" \ + " lsr %1, %1, 8\n" \ + "4: stb %1, [%2]\n" \ + "5:\n" \ + " .section .fixup,\"ax\"\n" \ + " .align 4\n" \ + "6: mov %0, 1\n" \ + " j 5b\n" \ + " .previous\n" \ + " .section __ex_table,\"a\"\n" \ + " .align 4\n" \ + " .long 1b, 6b\n" \ + " .long 2b, 6b\n" \ + " .long 3b, 6b\n" \ + " .long 4b, 6b\n" \ + " .previous\n" \ + : "=r" (err), "=&r" (v), "=&r" (a) \ + : "0" (err), "1" (v), "2" (a)); \ + \ + if (err) \ + goto fault; \ + } while (0) + +/* sysctl hooks */ +int unaligned_enabled __read_mostly = 1; /* Enabled by default */ +int no_unaligned_warning __read_mostly = 1; /* Only 1 warning by default */ + +static void fixup_load(struct disasm_state *state, struct pt_regs *regs, + struct callee_regs *cregs) +{ + int val; + + /* register write back */ + if ((state->aa == 1) || (state->aa == 2)) { + set_reg(state->wb_reg, state->src1 + state->src2, regs, cregs); + + if (state->aa == 2) + state->src2 = 0; + } + + if (state->zz == 0) { + get32_unaligned_check(val, state->src1 + state->src2); + } else { + get16_unaligned_check(val, state->src1 + state->src2); + + if (state->x) + val = (val << 16) >> 16; + } + + if (state->pref == 0) + set_reg(state->dest, val, regs, cregs); + + return; + +fault: state->fault = 1; +} + +static void fixup_store(struct disasm_state *state, struct pt_regs *regs, + struct callee_regs *cregs) +{ + /* register write back */ + if ((state->aa == 1) || (state->aa == 2)) { + set_reg(state->wb_reg, state->src2 + state->src3, regs, cregs); + + if (state->aa == 3) + state->src3 = 0; + } else if (state->aa == 3) { + if (state->zz == 2) { + set_reg(state->wb_reg, state->src2 + (state->src3 << 1), + regs, cregs); + } else if (!state->zz) { + set_reg(state->wb_reg, state->src2 + (state->src3 << 2), + regs, cregs); + } else { + goto fault; + } + } + + /* write fix-up */ + if (!state->zz) + put32_unaligned_check(state->src1, state->src2 + state->src3); + else + put16_unaligned_check(state->src1, state->src2 + state->src3); + + return; + +fault: state->fault = 1; +} + +/* + * Handle an unaligned access + * Returns 0 if successfully handled, 1 if some error happened + */ +int misaligned_fixup(unsigned long address, struct pt_regs *regs, + struct callee_regs *cregs) +{ + struct disasm_state state; + char buf[TASK_COMM_LEN]; + + /* handle user mode only and only if enabled by sysadmin */ + if (!user_mode(regs) || !unaligned_enabled) + return 1; + + if (no_unaligned_warning) { + pr_warn_once("%s(%d) made unaligned access which was emulated" + " by kernel assist\n. This can degrade application" + " performance significantly\n. To enable further" + " logging of such instances, please \n" + " echo 0 > /proc/sys/kernel/ignore-unaligned-usertrap\n", + get_task_comm(buf, current), task_pid_nr(current)); + } else { + /* Add rate limiting if it gets down to it */ + pr_warn("%s(%d): unaligned access to/from 0x%lx by PC: 0x%lx\n", + get_task_comm(buf, current), task_pid_nr(current), + address, regs->ret); + + } + + disasm_instr(regs->ret, &state, 1, regs, cregs); + + if (state.fault) + goto fault; + + /* ldb/stb should not have unaligned exception */ + if ((state.zz == 1) || (state.di)) + goto fault; + + if (!state.write) + fixup_load(&state, regs, cregs); + else + fixup_store(&state, regs, cregs); + + if (state.fault) + goto fault; + + /* clear any remanants of delay slot */ + if (delay_mode(regs)) { + regs->ret = regs->bta & ~1U; + regs->status32 &= ~STATUS_DE_MASK; + } else { + regs->ret += state.instr_len; + + /* handle zero-overhead-loop */ + if ((regs->ret == regs->lp_end) && (regs->lp_count)) { + regs->ret = regs->lp_start; + regs->lp_count--; + } + } + + perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address); + return 0; + +fault: + pr_err("Alignment trap: fault in fix-up %08lx at [<%08lx>]\n", + state.words[0], address); + + return 1; +} diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c new file mode 100644 index 000000000..74ad42560 --- /dev/null +++ b/arch/arc/kernel/unwind.c @@ -0,0 +1,1317 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * Copyright (C) 2002-2006 Novell, Inc. + * Jan Beulich <jbeulich@novell.com> + * + * A simple API for unwinding kernel stacks. This is used for + * debugging and error reporting purposes. The kernel doesn't need + * full-blown stack unwinding with all the bells and whistles, so there + * is not much point in implementing the full Dwarf2 unwind API. + */ + +#include <linux/sched.h> +#include <linux/module.h> +#include <linux/memblock.h> +#include <linux/sort.h> +#include <linux/slab.h> +#include <linux/stop_machine.h> +#include <linux/uaccess.h> +#include <linux/ptrace.h> +#include <asm/sections.h> +#include <asm/unaligned.h> +#include <asm/unwind.h> + +extern char __start_unwind[], __end_unwind[]; +/* extern const u8 __start_unwind_hdr[], __end_unwind_hdr[];*/ + +/* #define UNWIND_DEBUG */ + +#ifdef UNWIND_DEBUG +int dbg_unw; +#define unw_debug(fmt, ...) \ +do { \ + if (dbg_unw) \ + pr_info(fmt, ##__VA_ARGS__); \ +} while (0); +#else +#define unw_debug(fmt, ...) +#endif + +#define MAX_STACK_DEPTH 8 + +#define EXTRA_INFO(f) { \ + BUILD_BUG_ON_ZERO(offsetof(struct unwind_frame_info, f) \ + % sizeof_field(struct unwind_frame_info, f)) \ + + offsetof(struct unwind_frame_info, f) \ + / sizeof_field(struct unwind_frame_info, f), \ + sizeof_field(struct unwind_frame_info, f) \ + } +#define PTREGS_INFO(f) EXTRA_INFO(regs.f) + +static const struct { + unsigned offs:BITS_PER_LONG / 2; + unsigned width:BITS_PER_LONG / 2; +} reg_info[] = { +UNW_REGISTER_INFO}; + +#undef PTREGS_INFO +#undef EXTRA_INFO + +#ifndef REG_INVALID +#define REG_INVALID(r) (reg_info[r].width == 0) +#endif + +#define DW_CFA_nop 0x00 +#define DW_CFA_set_loc 0x01 +#define DW_CFA_advance_loc1 0x02 +#define DW_CFA_advance_loc2 0x03 +#define DW_CFA_advance_loc4 0x04 +#define DW_CFA_offset_extended 0x05 +#define DW_CFA_restore_extended 0x06 +#define DW_CFA_undefined 0x07 +#define DW_CFA_same_value 0x08 +#define DW_CFA_register 0x09 +#define DW_CFA_remember_state 0x0a +#define DW_CFA_restore_state 0x0b +#define DW_CFA_def_cfa 0x0c +#define DW_CFA_def_cfa_register 0x0d +#define DW_CFA_def_cfa_offset 0x0e +#define DW_CFA_def_cfa_expression 0x0f +#define DW_CFA_expression 0x10 +#define DW_CFA_offset_extended_sf 0x11 +#define DW_CFA_def_cfa_sf 0x12 +#define DW_CFA_def_cfa_offset_sf 0x13 +#define DW_CFA_val_offset 0x14 +#define DW_CFA_val_offset_sf 0x15 +#define DW_CFA_val_expression 0x16 +#define DW_CFA_lo_user 0x1c +#define DW_CFA_GNU_window_save 0x2d +#define DW_CFA_GNU_args_size 0x2e +#define DW_CFA_GNU_negative_offset_extended 0x2f +#define DW_CFA_hi_user 0x3f + +#define DW_EH_PE_FORM 0x07 +#define DW_EH_PE_native 0x00 +#define DW_EH_PE_leb128 0x01 +#define DW_EH_PE_data2 0x02 +#define DW_EH_PE_data4 0x03 +#define DW_EH_PE_data8 0x04 +#define DW_EH_PE_signed 0x08 +#define DW_EH_PE_ADJUST 0x70 +#define DW_EH_PE_abs 0x00 +#define DW_EH_PE_pcrel 0x10 +#define DW_EH_PE_textrel 0x20 +#define DW_EH_PE_datarel 0x30 +#define DW_EH_PE_funcrel 0x40 +#define DW_EH_PE_aligned 0x50 +#define DW_EH_PE_indirect 0x80 +#define DW_EH_PE_omit 0xff + +#define CIE_ID 0 + +typedef unsigned long uleb128_t; +typedef signed long sleb128_t; + +static struct unwind_table { + struct { + unsigned long pc; + unsigned long range; + } core, init; + const void *address; + unsigned long size; + const unsigned char *header; + unsigned long hdrsz; + struct unwind_table *link; + const char *name; +} root_table; + +struct unwind_item { + enum item_location { + Nowhere, + Memory, + Register, + Value + } where; + uleb128_t value; +}; + +struct unwind_state { + uleb128_t loc, org; + const u8 *cieStart, *cieEnd; + uleb128_t codeAlign; + sleb128_t dataAlign; + struct cfa { + uleb128_t reg, offs; + } cfa; + struct unwind_item regs[ARRAY_SIZE(reg_info)]; + unsigned stackDepth:8; + unsigned version:8; + const u8 *label; + const u8 *stack[MAX_STACK_DEPTH]; +}; + +static const struct cfa badCFA = { ARRAY_SIZE(reg_info), 1 }; + +static struct unwind_table *find_table(unsigned long pc) +{ + struct unwind_table *table; + + for (table = &root_table; table; table = table->link) + if ((pc >= table->core.pc + && pc < table->core.pc + table->core.range) + || (pc >= table->init.pc + && pc < table->init.pc + table->init.range)) + break; + + return table; +} + +static unsigned long read_pointer(const u8 **pLoc, + const void *end, signed ptrType); +static void init_unwind_hdr(struct unwind_table *table, + void *(*alloc) (unsigned long)); + +/* + * wrappers for header alloc (vs. calling one vs. other at call site) + * to elide section mismatches warnings + */ +static void *__init unw_hdr_alloc_early(unsigned long sz) +{ + return memblock_alloc_from(sz, sizeof(unsigned int), MAX_DMA_ADDRESS); +} + +static void init_unwind_table(struct unwind_table *table, const char *name, + const void *core_start, unsigned long core_size, + const void *init_start, unsigned long init_size, + const void *table_start, unsigned long table_size, + const u8 *header_start, unsigned long header_size) +{ + const u8 *ptr = header_start + 4; + const u8 *end = header_start + header_size; + + table->core.pc = (unsigned long)core_start; + table->core.range = core_size; + table->init.pc = (unsigned long)init_start; + table->init.range = init_size; + table->address = table_start; + table->size = table_size; + + /* See if the linker provided table looks valid. */ + if (header_size <= 4 + || header_start[0] != 1 + || (void *)read_pointer(&ptr, end, header_start[1]) != table_start + || header_start[2] == DW_EH_PE_omit + || read_pointer(&ptr, end, header_start[2]) <= 0 + || header_start[3] == DW_EH_PE_omit) + header_start = NULL; + + table->hdrsz = header_size; + smp_wmb(); + table->header = header_start; + table->link = NULL; + table->name = name; +} + +void __init arc_unwind_init(void) +{ + init_unwind_table(&root_table, "kernel", _text, _end - _text, NULL, 0, + __start_unwind, __end_unwind - __start_unwind, + NULL, 0); + /*__start_unwind_hdr, __end_unwind_hdr - __start_unwind_hdr);*/ + + init_unwind_hdr(&root_table, unw_hdr_alloc_early); +} + +static const u32 bad_cie, not_fde; +static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *); +static const u32 *__cie_for_fde(const u32 *fde); +static signed fde_pointer_type(const u32 *cie); + +struct eh_frame_hdr_table_entry { + unsigned long start, fde; +}; + +static int cmp_eh_frame_hdr_table_entries(const void *p1, const void *p2) +{ + const struct eh_frame_hdr_table_entry *e1 = p1; + const struct eh_frame_hdr_table_entry *e2 = p2; + + return (e1->start > e2->start) - (e1->start < e2->start); +} + +static void swap_eh_frame_hdr_table_entries(void *p1, void *p2, int size) +{ + struct eh_frame_hdr_table_entry *e1 = p1; + struct eh_frame_hdr_table_entry *e2 = p2; + unsigned long v; + + v = e1->start; + e1->start = e2->start; + e2->start = v; + v = e1->fde; + e1->fde = e2->fde; + e2->fde = v; +} + +static void init_unwind_hdr(struct unwind_table *table, + void *(*alloc) (unsigned long)) +{ + const u8 *ptr; + unsigned long tableSize = table->size, hdrSize; + unsigned n; + const u32 *fde; + struct { + u8 version; + u8 eh_frame_ptr_enc; + u8 fde_count_enc; + u8 table_enc; + unsigned long eh_frame_ptr; + unsigned int fde_count; + struct eh_frame_hdr_table_entry table[]; + } __attribute__ ((__packed__)) *header; + + if (table->header) + return; + + if (table->hdrsz) + pr_warn(".eh_frame_hdr for '%s' present but unusable\n", + table->name); + + if (tableSize & (sizeof(*fde) - 1)) + return; + + for (fde = table->address, n = 0; + tableSize > sizeof(*fde) && tableSize - sizeof(*fde) >= *fde; + tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { + const u32 *cie = cie_for_fde(fde, table); + signed ptrType; + + if (cie == ¬_fde) + continue; + if (cie == NULL || cie == &bad_cie) + goto ret_err; + ptrType = fde_pointer_type(cie); + if (ptrType < 0) + goto ret_err; + + ptr = (const u8 *)(fde + 2); + if (!read_pointer(&ptr, (const u8 *)(fde + 1) + *fde, + ptrType)) { + /* FIXME_Rajesh We have 4 instances of null addresses + * instead of the initial loc addr + * return; + */ + WARN(1, "unwinder: FDE->initial_location NULL %p\n", + (const u8 *)(fde + 1) + *fde); + } + ++n; + } + + if (tableSize || !n) + goto ret_err; + + hdrSize = 4 + sizeof(unsigned long) + sizeof(unsigned int) + + 2 * n * sizeof(unsigned long); + + header = alloc(hdrSize); + if (!header) + goto ret_err; + + header->version = 1; + header->eh_frame_ptr_enc = DW_EH_PE_abs | DW_EH_PE_native; + header->fde_count_enc = DW_EH_PE_abs | DW_EH_PE_data4; + header->table_enc = DW_EH_PE_abs | DW_EH_PE_native; + put_unaligned((unsigned long)table->address, &header->eh_frame_ptr); + BUILD_BUG_ON(offsetof(typeof(*header), fde_count) + % __alignof(typeof(header->fde_count))); + header->fde_count = n; + + BUILD_BUG_ON(offsetof(typeof(*header), table) + % __alignof(typeof(*header->table))); + for (fde = table->address, tableSize = table->size, n = 0; + tableSize; + tableSize -= sizeof(*fde) + *fde, fde += 1 + *fde / sizeof(*fde)) { + const u32 *cie = __cie_for_fde(fde); + + if (fde[1] == CIE_ID) + continue; /* this is a CIE */ + ptr = (const u8 *)(fde + 2); + header->table[n].start = read_pointer(&ptr, + (const u8 *)(fde + 1) + + *fde, + fde_pointer_type(cie)); + header->table[n].fde = (unsigned long)fde; + ++n; + } + WARN_ON(n != header->fde_count); + + sort(header->table, + n, + sizeof(*header->table), + cmp_eh_frame_hdr_table_entries, swap_eh_frame_hdr_table_entries); + + table->hdrsz = hdrSize; + smp_wmb(); + table->header = (const void *)header; + return; + +ret_err: + panic("Attention !!! Dwarf FDE parsing errors\n"); +} + +#ifdef CONFIG_MODULES +static void *unw_hdr_alloc(unsigned long sz) +{ + return kmalloc(sz, GFP_KERNEL); +} + +static struct unwind_table *last_table; + +/* Must be called with module_mutex held. */ +void *unwind_add_table(struct module *module, const void *table_start, + unsigned long table_size) +{ + struct unwind_table *table; + + if (table_size <= 0) + return NULL; + + table = kmalloc(sizeof(*table), GFP_KERNEL); + if (!table) + return NULL; + + init_unwind_table(table, module->name, + module->core_layout.base, module->core_layout.size, + module->init_layout.base, module->init_layout.size, + table_start, table_size, + NULL, 0); + + init_unwind_hdr(table, unw_hdr_alloc); + +#ifdef UNWIND_DEBUG + unw_debug("Table added for [%s] %lx %lx\n", + module->name, table->core.pc, table->core.range); +#endif + if (last_table) + last_table->link = table; + else + root_table.link = table; + last_table = table; + + return table; +} + +struct unlink_table_info { + struct unwind_table *table; + int init_only; +}; + +static int unlink_table(void *arg) +{ + struct unlink_table_info *info = arg; + struct unwind_table *table = info->table, *prev; + + for (prev = &root_table; prev->link && prev->link != table; + prev = prev->link) + ; + + if (prev->link) { + if (info->init_only) { + table->init.pc = 0; + table->init.range = 0; + info->table = NULL; + } else { + prev->link = table->link; + if (!prev->link) + last_table = prev; + } + } else + info->table = NULL; + + return 0; +} + +/* Must be called with module_mutex held. */ +void unwind_remove_table(void *handle, int init_only) +{ + struct unwind_table *table = handle; + struct unlink_table_info info; + + if (!table || table == &root_table) + return; + + if (init_only && table == last_table) { + table->init.pc = 0; + table->init.range = 0; + return; + } + + info.table = table; + info.init_only = init_only; + + unlink_table(&info); /* XXX: SMP */ + kfree(table->header); + kfree(table); +} + +#endif /* CONFIG_MODULES */ + +static uleb128_t get_uleb128(const u8 **pcur, const u8 *end) +{ + const u8 *cur = *pcur; + uleb128_t value; + unsigned shift; + + for (shift = 0, value = 0; cur < end; shift += 7) { + if (shift + 7 > 8 * sizeof(value) + && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) { + cur = end + 1; + break; + } + value |= (uleb128_t) (*cur & 0x7f) << shift; + if (!(*cur++ & 0x80)) + break; + } + *pcur = cur; + + return value; +} + +static sleb128_t get_sleb128(const u8 **pcur, const u8 *end) +{ + const u8 *cur = *pcur; + sleb128_t value; + unsigned shift; + + for (shift = 0, value = 0; cur < end; shift += 7) { + if (shift + 7 > 8 * sizeof(value) + && (*cur & 0x7fU) >= (1U << (8 * sizeof(value) - shift))) { + cur = end + 1; + break; + } + value |= (sleb128_t) (*cur & 0x7f) << shift; + if (!(*cur & 0x80)) { + value |= -(*cur++ & 0x40) << shift; + break; + } + } + *pcur = cur; + + return value; +} + +static const u32 *__cie_for_fde(const u32 *fde) +{ + const u32 *cie; + + cie = fde + 1 - fde[1] / sizeof(*fde); + + return cie; +} + +static const u32 *cie_for_fde(const u32 *fde, const struct unwind_table *table) +{ + const u32 *cie; + + if (!*fde || (*fde & (sizeof(*fde) - 1))) + return &bad_cie; + + if (fde[1] == CIE_ID) + return ¬_fde; /* this is a CIE */ + + if ((fde[1] & (sizeof(*fde) - 1))) +/* || fde[1] > (unsigned long)(fde + 1) - (unsigned long)table->address) */ + return NULL; /* this is not a valid FDE */ + + cie = __cie_for_fde(fde); + + if (*cie <= sizeof(*cie) + 4 || *cie >= fde[1] - sizeof(*fde) + || (*cie & (sizeof(*cie) - 1)) + || (cie[1] != CIE_ID)) + return NULL; /* this is not a (valid) CIE */ + return cie; +} + +static unsigned long read_pointer(const u8 **pLoc, const void *end, + signed ptrType) +{ + unsigned long value = 0; + union { + const u8 *p8; + const u16 *p16u; + const s16 *p16s; + const u32 *p32u; + const s32 *p32s; + const unsigned long *pul; + } ptr; + + if (ptrType < 0 || ptrType == DW_EH_PE_omit) + return 0; + ptr.p8 = *pLoc; + switch (ptrType & DW_EH_PE_FORM) { + case DW_EH_PE_data2: + if (end < (const void *)(ptr.p16u + 1)) + return 0; + if (ptrType & DW_EH_PE_signed) + value = get_unaligned((u16 *) ptr.p16s++); + else + value = get_unaligned((u16 *) ptr.p16u++); + break; + case DW_EH_PE_data4: +#ifdef CONFIG_64BIT + if (end < (const void *)(ptr.p32u + 1)) + return 0; + if (ptrType & DW_EH_PE_signed) + value = get_unaligned(ptr.p32s++); + else + value = get_unaligned(ptr.p32u++); + break; + case DW_EH_PE_data8: + BUILD_BUG_ON(sizeof(u64) != sizeof(value)); +#else + BUILD_BUG_ON(sizeof(u32) != sizeof(value)); +#endif + fallthrough; + case DW_EH_PE_native: + if (end < (const void *)(ptr.pul + 1)) + return 0; + value = get_unaligned((unsigned long *)ptr.pul++); + break; + case DW_EH_PE_leb128: + BUILD_BUG_ON(sizeof(uleb128_t) > sizeof(value)); + value = ptrType & DW_EH_PE_signed ? get_sleb128(&ptr.p8, end) + : get_uleb128(&ptr.p8, end); + if ((const void *)ptr.p8 > end) + return 0; + break; + default: + return 0; + } + switch (ptrType & DW_EH_PE_ADJUST) { + case DW_EH_PE_abs: + break; + case DW_EH_PE_pcrel: + value += (unsigned long)*pLoc; + break; + default: + return 0; + } + if ((ptrType & DW_EH_PE_indirect) + && __get_user(value, (unsigned long __user *)value)) + return 0; + *pLoc = ptr.p8; + + return value; +} + +static signed fde_pointer_type(const u32 *cie) +{ + const u8 *ptr = (const u8 *)(cie + 2); + unsigned version = *ptr; + + if (*++ptr) { + const char *aug; + const u8 *end = (const u8 *)(cie + 1) + *cie; + uleb128_t len; + + /* check if augmentation size is first (and thus present) */ + if (*ptr != 'z') + return -1; + + /* check if augmentation string is nul-terminated */ + aug = (const void *)ptr; + ptr = memchr(aug, 0, end - ptr); + if (ptr == NULL) + return -1; + + ++ptr; /* skip terminator */ + get_uleb128(&ptr, end); /* skip code alignment */ + get_sleb128(&ptr, end); /* skip data alignment */ + /* skip return address column */ + version <= 1 ? (void) ++ptr : (void)get_uleb128(&ptr, end); + len = get_uleb128(&ptr, end); /* augmentation length */ + + if (ptr + len < ptr || ptr + len > end) + return -1; + + end = ptr + len; + while (*++aug) { + if (ptr >= end) + return -1; + switch (*aug) { + case 'L': + ++ptr; + break; + case 'P':{ + signed ptrType = *ptr++; + + if (!read_pointer(&ptr, end, ptrType) + || ptr > end) + return -1; + } + break; + case 'R': + return *ptr; + default: + return -1; + } + } + } + return DW_EH_PE_native | DW_EH_PE_abs; +} + +static int advance_loc(unsigned long delta, struct unwind_state *state) +{ + state->loc += delta * state->codeAlign; + + /* FIXME_Rajesh: Probably we are defining for the initial range as well; + return delta > 0; + */ + unw_debug("delta %3lu => loc 0x%lx: ", delta, state->loc); + return 1; +} + +static void set_rule(uleb128_t reg, enum item_location where, uleb128_t value, + struct unwind_state *state) +{ + if (reg < ARRAY_SIZE(state->regs)) { + state->regs[reg].where = where; + state->regs[reg].value = value; + +#ifdef UNWIND_DEBUG + unw_debug("r%lu: ", reg); + switch (where) { + case Nowhere: + unw_debug("s "); + break; + case Memory: + unw_debug("c(%lu) ", value); + break; + case Register: + unw_debug("r(%lu) ", value); + break; + case Value: + unw_debug("v(%lu) ", value); + break; + default: + break; + } +#endif + } +} + +static int processCFI(const u8 *start, const u8 *end, unsigned long targetLoc, + signed ptrType, struct unwind_state *state) +{ + union { + const u8 *p8; + const u16 *p16; + const u32 *p32; + } ptr; + int result = 1; + u8 opcode; + + if (start != state->cieStart) { + state->loc = state->org; + result = + processCFI(state->cieStart, state->cieEnd, 0, ptrType, + state); + if (targetLoc == 0 && state->label == NULL) + return result; + } + for (ptr.p8 = start; result && ptr.p8 < end;) { + switch (*ptr.p8 >> 6) { + uleb128_t value; + + case 0: + opcode = *ptr.p8++; + + switch (opcode) { + case DW_CFA_nop: + unw_debug("cfa nop "); + break; + case DW_CFA_set_loc: + state->loc = read_pointer(&ptr.p8, end, + ptrType); + if (state->loc == 0) + result = 0; + unw_debug("cfa_set_loc: 0x%lx ", state->loc); + break; + case DW_CFA_advance_loc1: + unw_debug("\ncfa advance loc1:"); + result = ptr.p8 < end + && advance_loc(*ptr.p8++, state); + break; + case DW_CFA_advance_loc2: + value = *ptr.p8++; + value += *ptr.p8++ << 8; + unw_debug("\ncfa advance loc2:"); + result = ptr.p8 <= end + 2 + /* && advance_loc(*ptr.p16++, state); */ + && advance_loc(value, state); + break; + case DW_CFA_advance_loc4: + unw_debug("\ncfa advance loc4:"); + result = ptr.p8 <= end + 4 + && advance_loc(*ptr.p32++, state); + break; + case DW_CFA_offset_extended: + value = get_uleb128(&ptr.p8, end); + unw_debug("cfa_offset_extended: "); + set_rule(value, Memory, + get_uleb128(&ptr.p8, end), state); + break; + case DW_CFA_val_offset: + value = get_uleb128(&ptr.p8, end); + set_rule(value, Value, + get_uleb128(&ptr.p8, end), state); + break; + case DW_CFA_offset_extended_sf: + value = get_uleb128(&ptr.p8, end); + set_rule(value, Memory, + get_sleb128(&ptr.p8, end), state); + break; + case DW_CFA_val_offset_sf: + value = get_uleb128(&ptr.p8, end); + set_rule(value, Value, + get_sleb128(&ptr.p8, end), state); + break; + case DW_CFA_restore_extended: + unw_debug("cfa_restore_extended: "); + case DW_CFA_undefined: + unw_debug("cfa_undefined: "); + case DW_CFA_same_value: + unw_debug("cfa_same_value: "); + set_rule(get_uleb128(&ptr.p8, end), Nowhere, 0, + state); + break; + case DW_CFA_register: + unw_debug("cfa_register: "); + value = get_uleb128(&ptr.p8, end); + set_rule(value, + Register, + get_uleb128(&ptr.p8, end), state); + break; + case DW_CFA_remember_state: + unw_debug("cfa_remember_state: "); + if (ptr.p8 == state->label) { + state->label = NULL; + return 1; + } + if (state->stackDepth >= MAX_STACK_DEPTH) + return 0; + state->stack[state->stackDepth++] = ptr.p8; + break; + case DW_CFA_restore_state: + unw_debug("cfa_restore_state: "); + if (state->stackDepth) { + const uleb128_t loc = state->loc; + const u8 *label = state->label; + + state->label = + state->stack[state->stackDepth - 1]; + memcpy(&state->cfa, &badCFA, + sizeof(state->cfa)); + memset(state->regs, 0, + sizeof(state->regs)); + state->stackDepth = 0; + result = + processCFI(start, end, 0, ptrType, + state); + state->loc = loc; + state->label = label; + } else + return 0; + break; + case DW_CFA_def_cfa: + state->cfa.reg = get_uleb128(&ptr.p8, end); + unw_debug("cfa_def_cfa: r%lu ", state->cfa.reg); + fallthrough; + case DW_CFA_def_cfa_offset: + state->cfa.offs = get_uleb128(&ptr.p8, end); + unw_debug("cfa_def_cfa_offset: 0x%lx ", + state->cfa.offs); + break; + case DW_CFA_def_cfa_sf: + state->cfa.reg = get_uleb128(&ptr.p8, end); + fallthrough; + case DW_CFA_def_cfa_offset_sf: + state->cfa.offs = get_sleb128(&ptr.p8, end) + * state->dataAlign; + break; + case DW_CFA_def_cfa_register: + unw_debug("cfa_def_cfa_register: "); + state->cfa.reg = get_uleb128(&ptr.p8, end); + break; + /*todo case DW_CFA_def_cfa_expression: */ + /*todo case DW_CFA_expression: */ + /*todo case DW_CFA_val_expression: */ + case DW_CFA_GNU_args_size: + get_uleb128(&ptr.p8, end); + break; + case DW_CFA_GNU_negative_offset_extended: + value = get_uleb128(&ptr.p8, end); + set_rule(value, + Memory, + (uleb128_t) 0 - get_uleb128(&ptr.p8, + end), + state); + break; + case DW_CFA_GNU_window_save: + default: + unw_debug("UNKNOWN OPCODE 0x%x\n", opcode); + result = 0; + break; + } + break; + case 1: + unw_debug("\ncfa_adv_loc: "); + result = advance_loc(*ptr.p8++ & 0x3f, state); + break; + case 2: + unw_debug("cfa_offset: "); + value = *ptr.p8++ & 0x3f; + set_rule(value, Memory, get_uleb128(&ptr.p8, end), + state); + break; + case 3: + unw_debug("cfa_restore: "); + set_rule(*ptr.p8++ & 0x3f, Nowhere, 0, state); + break; + } + + if (ptr.p8 > end) + result = 0; + if (result && targetLoc != 0 && targetLoc < state->loc) + return 1; + } + + return result && ptr.p8 == end && (targetLoc == 0 || ( + /*todo While in theory this should apply, gcc in practice omits + everything past the function prolog, and hence the location + never reaches the end of the function. + targetLoc < state->loc && */ state->label == NULL)); +} + +/* Unwind to previous to frame. Returns 0 if successful, negative + * number in case of an error. */ +int arc_unwind(struct unwind_frame_info *frame) +{ +#define FRAME_REG(r, t) (((t *)frame)[reg_info[r].offs]) + const u32 *fde = NULL, *cie = NULL; + const u8 *ptr = NULL, *end = NULL; + unsigned long pc = UNW_PC(frame) - frame->call_frame; + unsigned long startLoc = 0, endLoc = 0, cfa; + unsigned i; + signed ptrType = -1; + uleb128_t retAddrReg = 0; + const struct unwind_table *table; + struct unwind_state state; + unsigned long *fptr; + unsigned long addr; + + unw_debug("\n\nUNWIND FRAME:\n"); + unw_debug("PC: 0x%lx BLINK: 0x%lx, SP: 0x%lx, FP: 0x%x\n", + UNW_PC(frame), UNW_BLINK(frame), UNW_SP(frame), + UNW_FP(frame)); + + if (UNW_PC(frame) == 0) + return -EINVAL; + +#ifdef UNWIND_DEBUG + { + unsigned long *sptr = (unsigned long *)UNW_SP(frame); + unw_debug("\nStack Dump:\n"); + for (i = 0; i < 20; i++, sptr++) + unw_debug("0x%p: 0x%lx\n", sptr, *sptr); + unw_debug("\n"); + } +#endif + + table = find_table(pc); + if (table != NULL + && !(table->size & (sizeof(*fde) - 1))) { + const u8 *hdr = table->header; + unsigned long tableSize; + + smp_rmb(); + if (hdr && hdr[0] == 1) { + switch (hdr[3] & DW_EH_PE_FORM) { + case DW_EH_PE_native: + tableSize = sizeof(unsigned long); + break; + case DW_EH_PE_data2: + tableSize = 2; + break; + case DW_EH_PE_data4: + tableSize = 4; + break; + case DW_EH_PE_data8: + tableSize = 8; + break; + default: + tableSize = 0; + break; + } + ptr = hdr + 4; + end = hdr + table->hdrsz; + if (tableSize && read_pointer(&ptr, end, hdr[1]) + == (unsigned long)table->address + && (i = read_pointer(&ptr, end, hdr[2])) > 0 + && i == (end - ptr) / (2 * tableSize) + && !((end - ptr) % (2 * tableSize))) { + do { + const u8 *cur = + ptr + (i / 2) * (2 * tableSize); + + startLoc = read_pointer(&cur, + cur + tableSize, + hdr[3]); + if (pc < startLoc) + i /= 2; + else { + ptr = cur - tableSize; + i = (i + 1) / 2; + } + } while (startLoc && i > 1); + if (i == 1 + && (startLoc = read_pointer(&ptr, + ptr + tableSize, + hdr[3])) != 0 + && pc >= startLoc) + fde = (void *)read_pointer(&ptr, + ptr + + tableSize, + hdr[3]); + } + } + + if (fde != NULL) { + cie = cie_for_fde(fde, table); + ptr = (const u8 *)(fde + 2); + if (cie != NULL + && cie != &bad_cie + && cie != ¬_fde + && (ptrType = fde_pointer_type(cie)) >= 0 + && read_pointer(&ptr, + (const u8 *)(fde + 1) + *fde, + ptrType) == startLoc) { + if (!(ptrType & DW_EH_PE_indirect)) + ptrType &= + DW_EH_PE_FORM | DW_EH_PE_signed; + endLoc = + startLoc + read_pointer(&ptr, + (const u8 *)(fde + + 1) + + *fde, ptrType); + if (pc >= endLoc) { + fde = NULL; + cie = NULL; + } + } else { + fde = NULL; + cie = NULL; + } + } + } + if (cie != NULL) { + memset(&state, 0, sizeof(state)); + state.cieEnd = ptr; /* keep here temporarily */ + ptr = (const u8 *)(cie + 2); + end = (const u8 *)(cie + 1) + *cie; + frame->call_frame = 1; + if (*++ptr) { + /* check if augmentation size is first (thus present) */ + if (*ptr == 'z') { + while (++ptr < end && *ptr) { + switch (*ptr) { + /* chk for ignorable or already handled + * nul-terminated augmentation string */ + case 'L': + case 'P': + case 'R': + continue; + case 'S': + frame->call_frame = 0; + continue; + default: + break; + } + break; + } + } + if (ptr >= end || *ptr) + cie = NULL; + } + ++ptr; + } + if (cie != NULL) { + /* get code alignment factor */ + state.codeAlign = get_uleb128(&ptr, end); + /* get data alignment factor */ + state.dataAlign = get_sleb128(&ptr, end); + if (state.codeAlign == 0 || state.dataAlign == 0 || ptr >= end) + cie = NULL; + else { + retAddrReg = + state.version <= 1 ? *ptr++ : get_uleb128(&ptr, + end); + unw_debug("CIE Frame Info:\n"); + unw_debug("return Address register 0x%lx\n", + retAddrReg); + unw_debug("data Align: %ld\n", state.dataAlign); + unw_debug("code Align: %lu\n", state.codeAlign); + /* skip augmentation */ + if (((const char *)(cie + 2))[1] == 'z') { + uleb128_t augSize = get_uleb128(&ptr, end); + + ptr += augSize; + } + if (ptr > end || retAddrReg >= ARRAY_SIZE(reg_info) + || REG_INVALID(retAddrReg) + || reg_info[retAddrReg].width != + sizeof(unsigned long)) + cie = NULL; + } + } + if (cie != NULL) { + state.cieStart = ptr; + ptr = state.cieEnd; + state.cieEnd = end; + end = (const u8 *)(fde + 1) + *fde; + /* skip augmentation */ + if (((const char *)(cie + 2))[1] == 'z') { + uleb128_t augSize = get_uleb128(&ptr, end); + + if ((ptr += augSize) > end) + fde = NULL; + } + } + if (cie == NULL || fde == NULL) { +#ifdef CONFIG_FRAME_POINTER + unsigned long top, bottom; + + top = STACK_TOP_UNW(frame->task); + bottom = STACK_BOTTOM_UNW(frame->task); +#if FRAME_RETADDR_OFFSET < 0 + if (UNW_SP(frame) < top && UNW_FP(frame) <= UNW_SP(frame) + && bottom < UNW_FP(frame) +#else + if (UNW_SP(frame) > top && UNW_FP(frame) >= UNW_SP(frame) + && bottom > UNW_FP(frame) +#endif + && !((UNW_SP(frame) | UNW_FP(frame)) + & (sizeof(unsigned long) - 1))) { + unsigned long link; + + if (!__get_user(link, (unsigned long *) + (UNW_FP(frame) + FRAME_LINK_OFFSET)) +#if FRAME_RETADDR_OFFSET < 0 + && link > bottom && link < UNW_FP(frame) +#else + && link > UNW_FP(frame) && link < bottom +#endif + && !(link & (sizeof(link) - 1)) + && !__get_user(UNW_PC(frame), + (unsigned long *)(UNW_FP(frame) + + FRAME_RETADDR_OFFSET))) + { + UNW_SP(frame) = + UNW_FP(frame) + FRAME_RETADDR_OFFSET +#if FRAME_RETADDR_OFFSET < 0 + - +#else + + +#endif + sizeof(UNW_PC(frame)); + UNW_FP(frame) = link; + return 0; + } + } +#endif + return -ENXIO; + } + state.org = startLoc; + memcpy(&state.cfa, &badCFA, sizeof(state.cfa)); + + unw_debug("\nProcess instructions\n"); + + /* process instructions + * For ARC, we optimize by having blink(retAddrReg) with + * the sameValue in the leaf function, so we should not check + * state.regs[retAddrReg].where == Nowhere + */ + if (!processCFI(ptr, end, pc, ptrType, &state) + || state.loc > endLoc +/* || state.regs[retAddrReg].where == Nowhere */ + || state.cfa.reg >= ARRAY_SIZE(reg_info) + || reg_info[state.cfa.reg].width != sizeof(unsigned long) + || state.cfa.offs % sizeof(unsigned long)) + return -EIO; + +#ifdef UNWIND_DEBUG + unw_debug("\n"); + + unw_debug("\nRegister State Based on the rules parsed from FDE:\n"); + for (i = 0; i < ARRAY_SIZE(state.regs); ++i) { + + if (REG_INVALID(i)) + continue; + + switch (state.regs[i].where) { + case Nowhere: + break; + case Memory: + unw_debug(" r%d: c(%lu),", i, state.regs[i].value); + break; + case Register: + unw_debug(" r%d: r(%lu),", i, state.regs[i].value); + break; + case Value: + unw_debug(" r%d: v(%lu),", i, state.regs[i].value); + break; + } + } + + unw_debug("\n"); +#endif + + /* update frame */ + if (frame->call_frame + && !UNW_DEFAULT_RA(state.regs[retAddrReg], state.dataAlign)) + frame->call_frame = 0; + cfa = FRAME_REG(state.cfa.reg, unsigned long) + state.cfa.offs; + startLoc = min_t(unsigned long, UNW_SP(frame), cfa); + endLoc = max_t(unsigned long, UNW_SP(frame), cfa); + if (STACK_LIMIT(startLoc) != STACK_LIMIT(endLoc)) { + startLoc = min(STACK_LIMIT(cfa), cfa); + endLoc = max(STACK_LIMIT(cfa), cfa); + } + + unw_debug("\nCFA reg: 0x%lx, offset: 0x%lx => 0x%lx\n", + state.cfa.reg, state.cfa.offs, cfa); + + for (i = 0; i < ARRAY_SIZE(state.regs); ++i) { + if (REG_INVALID(i)) { + if (state.regs[i].where == Nowhere) + continue; + return -EIO; + } + switch (state.regs[i].where) { + default: + break; + case Register: + if (state.regs[i].value >= ARRAY_SIZE(reg_info) + || REG_INVALID(state.regs[i].value) + || reg_info[i].width > + reg_info[state.regs[i].value].width) + return -EIO; + switch (reg_info[state.regs[i].value].width) { + case sizeof(u8): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u8); + break; + case sizeof(u16): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u16); + break; + case sizeof(u32): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u32); + break; +#ifdef CONFIG_64BIT + case sizeof(u64): + state.regs[i].value = + FRAME_REG(state.regs[i].value, const u64); + break; +#endif + default: + return -EIO; + } + break; + } + } + + unw_debug("\nRegister state after evaluation with realtime Stack:\n"); + fptr = (unsigned long *)(&frame->regs); + for (i = 0; i < ARRAY_SIZE(state.regs); ++i, fptr++) { + + if (REG_INVALID(i)) + continue; + switch (state.regs[i].where) { + case Nowhere: + if (reg_info[i].width != sizeof(UNW_SP(frame)) + || &FRAME_REG(i, __typeof__(UNW_SP(frame))) + != &UNW_SP(frame)) + continue; + UNW_SP(frame) = cfa; + break; + case Register: + switch (reg_info[i].width) { + case sizeof(u8): + FRAME_REG(i, u8) = state.regs[i].value; + break; + case sizeof(u16): + FRAME_REG(i, u16) = state.regs[i].value; + break; + case sizeof(u32): + FRAME_REG(i, u32) = state.regs[i].value; + break; +#ifdef CONFIG_64BIT + case sizeof(u64): + FRAME_REG(i, u64) = state.regs[i].value; + break; +#endif + default: + return -EIO; + } + break; + case Value: + if (reg_info[i].width != sizeof(unsigned long)) + return -EIO; + FRAME_REG(i, unsigned long) = cfa + state.regs[i].value + * state.dataAlign; + break; + case Memory: + addr = cfa + state.regs[i].value * state.dataAlign; + + if ((state.regs[i].value * state.dataAlign) + % sizeof(unsigned long) + || addr < startLoc + || addr + sizeof(unsigned long) < addr + || addr + sizeof(unsigned long) > endLoc) + return -EIO; + + switch (reg_info[i].width) { + case sizeof(u8): + __get_user(FRAME_REG(i, u8), + (u8 __user *)addr); + break; + case sizeof(u16): + __get_user(FRAME_REG(i, u16), + (u16 __user *)addr); + break; + case sizeof(u32): + __get_user(FRAME_REG(i, u32), + (u32 __user *)addr); + break; +#ifdef CONFIG_64BIT + case sizeof(u64): + __get_user(FRAME_REG(i, u64), + (u64 __user *)addr); + break; +#endif + default: + return -EIO; + } + + break; + } + unw_debug("r%d: 0x%lx ", i, *fptr); + } + + return 0; +#undef FRAME_REG +} +EXPORT_SYMBOL(arc_unwind); diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S new file mode 100644 index 000000000..f67e4ad7b --- /dev/null +++ b/arch/arc/kernel/vmlinux.lds.S @@ -0,0 +1,156 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + */ + +#include <asm-generic/vmlinux.lds.h> +#include <asm/cache.h> +#include <asm/page.h> +#include <asm/thread_info.h> + +OUTPUT_ARCH(arc) +ENTRY(res_service) + +#ifdef CONFIG_CPU_BIG_ENDIAN +jiffies = jiffies_64 + 4; +#else +jiffies = jiffies_64; +#endif + +SECTIONS +{ + /* + * ICCM starts at 0x8000_0000. So if kernel is relocated to some other + * address, make sure peripheral at 0x8z doesn't clash with ICCM + * Essentially vector is also in ICCM. + */ + + . = CONFIG_LINUX_LINK_BASE; + + _int_vec_base_lds = .; + .vector : { + *(.vector) + . = ALIGN(PAGE_SIZE); + } + +#ifdef CONFIG_ARC_HAS_ICCM + .text.arcfp : { + *(.text.arcfp) + . = ALIGN(CONFIG_ARC_ICCM_SZ * 1024); + } +#endif + + /* + * The reason for having a seperate subsection .init.ramfs is to + * prevent objump from including it in kernel dumps + * + * Reason for having .init.ramfs above .init is to make sure that the + * binary blob is tucked away to one side, reducing the displacement + * between .init.text and .text, avoiding any possible relocation + * errors because of calls from .init.text to .text + * Yes such calls do exist. e.g. + * decompress_inflate.c:gunzip( ) -> zlib_inflate_workspace( ) + */ + + __init_begin = .; + + .init.ramfs : { INIT_RAM_FS } + + . = ALIGN(PAGE_SIZE); + _stext = .; + + HEAD_TEXT_SECTION + INIT_TEXT_SECTION(L1_CACHE_BYTES) + + /* INIT_DATA_SECTION open-coded: special INIT_RAM_FS handling */ + .init.data : { + INIT_DATA + INIT_SETUP(L1_CACHE_BYTES) + INIT_CALLS + CON_INITCALL + } + + .init.arch.info : { + __arch_info_begin = .; + *(.arch.info.init) + __arch_info_end = .; + } + + PERCPU_SECTION(L1_CACHE_BYTES) + + . = ALIGN(PAGE_SIZE); + __init_end = .; + + .text : { + _text = .; + TEXT_TEXT + SCHED_TEXT + CPUIDLE_TEXT + LOCK_TEXT + KPROBES_TEXT + IRQENTRY_TEXT + SOFTIRQENTRY_TEXT + *(.fixup) + *(.gnu.warning) + } + EXCEPTION_TABLE(L1_CACHE_BYTES) + _etext = .; + + _sdata = .; + RO_DATA(PAGE_SIZE) + + /* + * 1. this is .data essentially + * 2. THREAD_SIZE for init.task, must be kernel-stk sz aligned + */ + RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE) + + _edata = .; + + BSS_SECTION(4, 4, 4) + +#ifdef CONFIG_ARC_DW2_UNWIND + . = ALIGN(PAGE_SIZE); + .eh_frame : { + __start_unwind = .; + *(.eh_frame) + __end_unwind = .; + } +#else + /DISCARD/ : { *(.eh_frame) } +#endif + + . = ALIGN(PAGE_SIZE); + _end = . ; + + STABS_DEBUG + ELF_DETAILS + DISCARDS + + .arcextmap 0 : { + *(.gnu.linkonce.arcextmap.*) + *(.arcextmap.*) + } + +#ifndef CONFIG_DEBUG_INFO + /DISCARD/ : { *(.debug_frame) } + /DISCARD/ : { *(.debug_aranges) } + /DISCARD/ : { *(.debug_pubnames) } + /DISCARD/ : { *(.debug_info) } + /DISCARD/ : { *(.debug_abbrev) } + /DISCARD/ : { *(.debug_line) } + /DISCARD/ : { *(.debug_str) } + /DISCARD/ : { *(.debug_loc) } + /DISCARD/ : { *(.debug_macinfo) } + /DISCARD/ : { *(.debug_ranges) } +#endif + +#ifdef CONFIG_ARC_HAS_DCCM + . = CONFIG_ARC_DCCM_BASE; + __arc_dccm_base = .; + .data.arcfp : { + *(.data.arcfp) + } + . = ALIGN(CONFIG_ARC_DCCM_SZ * 1024); +#endif +} |