From: GuanXuetao Date: Sat, 15 Jan 2011 10:16:21 +0000 (+0800) Subject: unicore32 core architecture: process/thread related codes X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=f73670e8a55c11d47c28dca35dc4bc7dfbd4e6eb;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git unicore32 core architecture: process/thread related codes This patch implements process/thread related codes. Backtrace and stacktrace are here. Signed-off-by: Guan Xuetao Reviewed-by: Arnd Bergmann --- diff --git a/arch/unicore32/include/asm/stacktrace.h b/arch/unicore32/include/asm/stacktrace.h new file mode 100644 index 000000000000..76edc65a5871 --- /dev/null +++ b/arch/unicore32/include/asm/stacktrace.h @@ -0,0 +1,31 @@ +/* + * linux/arch/unicore32/include/asm/stacktrace.h + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef __UNICORE_STACKTRACE_H__ +#define __UNICORE_STACKTRACE_H__ + +struct stackframe { + unsigned long fp; + unsigned long sp; + unsigned long lr; + unsigned long pc; +}; + +#ifdef CONFIG_FRAME_POINTER +extern int unwind_frame(struct stackframe *frame); +#else +#define unwind_frame(f) (-EINVAL) +#endif +extern void walk_stackframe(struct stackframe *frame, + int (*fn)(struct stackframe *, void *), void *data); + +#endif /* __UNICORE_STACKTRACE_H__ */ diff --git a/arch/unicore32/include/asm/thread_info.h b/arch/unicore32/include/asm/thread_info.h new file mode 100644 index 000000000000..c270e9e04861 --- /dev/null +++ b/arch/unicore32/include/asm/thread_info.h @@ -0,0 +1,154 @@ +/* + * linux/arch/unicore32/include/asm/thread_info.h + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef __UNICORE_THREAD_INFO_H__ +#define __UNICORE_THREAD_INFO_H__ + +#ifdef __KERNEL__ + +#include +#include + +#define THREAD_SIZE_ORDER 1 +#define THREAD_SIZE 8192 +#define THREAD_START_SP (THREAD_SIZE - 8) + +#ifndef __ASSEMBLY__ + +struct task_struct; +struct exec_domain; + +#include + +typedef struct { + unsigned long seg; +} mm_segment_t; + +struct cpu_context_save { + __u32 r4; + __u32 r5; + __u32 r6; + __u32 r7; + __u32 r8; + __u32 r9; + __u32 r10; + __u32 r11; + __u32 r12; + __u32 r13; + __u32 r14; + __u32 r15; + __u32 r16; + __u32 r17; + __u32 r18; + __u32 r19; + __u32 r20; + __u32 r21; + __u32 r22; + __u32 r23; + __u32 r24; + __u32 r25; + __u32 r26; + __u32 fp; + __u32 sp; + __u32 pc; +}; + +/* + * low level task data that entry.S needs immediate access to. + * __switch_to() assumes cpu_context follows immediately after cpu_domain. + */ +struct thread_info { + unsigned long flags; /* low level flags */ + int preempt_count; /* 0 => preemptable */ + /* <0 => bug */ + mm_segment_t addr_limit; /* address limit */ + struct task_struct *task; /* main task structure */ + struct exec_domain *exec_domain; /* execution domain */ + __u32 cpu; /* cpu */ + struct cpu_context_save cpu_context; /* cpu context */ + __u32 syscall; /* syscall number */ + __u8 used_cp[16]; /* thread used copro */ +#ifdef CONFIG_UNICORE_FPU_F64 + struct fp_state fpstate __attribute__((aligned(8))); +#endif + struct restart_block restart_block; +}; + +#define INIT_THREAD_INFO(tsk) \ +{ \ + .task = &tsk, \ + .exec_domain = &default_exec_domain, \ + .flags = 0, \ + .preempt_count = INIT_PREEMPT_COUNT, \ + .addr_limit = KERNEL_DS, \ + .restart_block = { \ + .fn = do_no_restart_syscall, \ + }, \ +} + +#define init_thread_info (init_thread_union.thread_info) +#define init_stack (init_thread_union.stack) + +/* + * how to get the thread information struct from C + */ +static inline struct thread_info *current_thread_info(void) __attribute_const__; + +static inline struct thread_info *current_thread_info(void) +{ + register unsigned long sp asm ("sp"); + return (struct thread_info *)(sp & ~(THREAD_SIZE - 1)); +} + +#define thread_saved_pc(tsk) \ + ((unsigned long)(task_thread_info(tsk)->cpu_context.pc)) +#define thread_saved_sp(tsk) \ + ((unsigned long)(task_thread_info(tsk)->cpu_context.sp)) +#define thread_saved_fp(tsk) \ + ((unsigned long)(task_thread_info(tsk)->cpu_context.fp)) + +#endif + +/* + * We use bit 30 of the preempt_count to indicate that kernel + * preemption is occurring. See . + */ +#define PREEMPT_ACTIVE 0x40000000 + +/* + * thread information flags: + * TIF_SYSCALL_TRACE - syscall trace active + * TIF_SIGPENDING - signal pending + * TIF_NEED_RESCHED - rescheduling necessary + * TIF_NOTIFY_RESUME - callback before returning to user + */ +#define TIF_SIGPENDING 0 +#define TIF_NEED_RESCHED 1 +#define TIF_NOTIFY_RESUME 2 /* callback before returning to user */ +#define TIF_SYSCALL_TRACE 8 +#define TIF_MEMDIE 18 +#define TIF_FREEZE 19 +#define TIF_RESTORE_SIGMASK 20 + +#define _TIF_SIGPENDING (1 << TIF_SIGPENDING) +#define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) +#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) +#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) +#define _TIF_FREEZE (1 << TIF_FREEZE) +#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK) + +/* + * Change these and you break ASM code in entry-common.S + */ +#define _TIF_WORK_MASK 0x000000ff + +#endif /* __KERNEL__ */ +#endif /* __UNICORE_THREAD_INFO_H__ */ diff --git a/arch/unicore32/kernel/init_task.c b/arch/unicore32/kernel/init_task.c new file mode 100644 index 000000000000..a35a1e50e4f4 --- /dev/null +++ b/arch/unicore32/kernel/init_task.c @@ -0,0 +1,44 @@ +/* + * linux/arch/unicore32/kernel/init_task.c + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +static struct signal_struct init_signals = INIT_SIGNALS(init_signals); +static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand); +/* + * Initial thread structure. + * + * We need to make sure that this is 8192-byte aligned due to the + * way process stacks are handled. This is done by making sure + * the linker maps this in the .text segment right after head.S, + * and making head.S ensure the proper alignment. + * + * The things we do for performance.. + */ +union thread_union init_thread_union __init_task_data = { + INIT_THREAD_INFO(init_task) }; + +/* + * Initial task structure. + * + * All other task structs will be allocated on slabs in fork.c + */ +struct task_struct init_task = INIT_TASK(init_task); +EXPORT_SYMBOL(init_task); diff --git a/arch/unicore32/kernel/process.c b/arch/unicore32/kernel/process.c new file mode 100644 index 000000000000..8d4a273ae086 --- /dev/null +++ b/arch/unicore32/kernel/process.c @@ -0,0 +1,389 @@ +/* + * linux/arch/unicore32/kernel/process.c + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include "setup.h" + +static const char * const processor_modes[] = { + "UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07", + "UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F", + "USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT", + "UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR" +}; + +/* + * The idle thread, has rather strange semantics for calling pm_idle, + * but this is what x86 does and we need to do the same, so that + * things like cpuidle get called in the same way. + */ +void cpu_idle(void) +{ + /* endless idle loop with no priority at all */ + while (1) { + tick_nohz_stop_sched_tick(1); + while (!need_resched()) { + local_irq_disable(); + stop_critical_timings(); + cpu_do_idle(); + local_irq_enable(); + start_critical_timings(); + } + tick_nohz_restart_sched_tick(); + preempt_enable_no_resched(); + schedule(); + preempt_disable(); + } +} + +static char reboot_mode = 'h'; + +int __init reboot_setup(char *str) +{ + reboot_mode = str[0]; + return 1; +} + +__setup("reboot=", reboot_setup); + +void machine_halt(void) +{ + gpio_set_value(GPO_SOFT_OFF, 0); +} + +/* + * Function pointers to optional machine specific functions + */ +void (*pm_power_off)(void) = NULL; + +void machine_power_off(void) +{ + if (pm_power_off) + pm_power_off(); + machine_halt(); +} + +void machine_restart(char *cmd) +{ + /* Disable interrupts first */ + local_irq_disable(); + + /* + * Tell the mm system that we are going to reboot - + * we may need it to insert some 1:1 mappings so that + * soft boot works. + */ + setup_mm_for_reboot(reboot_mode); + + /* Clean and invalidate caches */ + flush_cache_all(); + + /* Turn off caching */ + cpu_proc_fin(); + + /* Push out any further dirty data, and ensure cache is empty */ + flush_cache_all(); + + /* + * Now handle reboot code. + */ + if (reboot_mode == 's') { + /* Jump into ROM at address 0xffff0000 */ + cpu_reset(VECTORS_BASE); + } else { + PM_PLLSYSCFG = 0x00002001; /* cpu clk = 250M */ + PM_PLLDDRCFG = 0x00100800; /* ddr clk = 44M */ + PM_PLLVGACFG = 0x00002001; /* vga clk = 250M */ + + /* Use on-chip reset capability */ + /* following instructions must be in one icache line */ + __asm__ __volatile__( + " .align 5\n\t" + " stw %1, [%0]\n\t" + "201: ldw r0, [%0]\n\t" + " cmpsub.a r0, #0\n\t" + " bne 201b\n\t" + " stw %3, [%2]\n\t" + " nop; nop; nop\n\t" + /* prefetch 3 instructions at most */ + : + : "r" ((unsigned long)&PM_PMCR), + "r" (PM_PMCR_CFBSYS | PM_PMCR_CFBDDR + | PM_PMCR_CFBVGA), + "r" ((unsigned long)&RESETC_SWRR), + "r" (RESETC_SWRR_SRB) + : "r0", "memory"); + } + + /* + * Whoops - the architecture was unable to reboot. + * Tell the user! + */ + mdelay(1000); + printk(KERN_EMERG "Reboot failed -- System halted\n"); + do { } while (1); +} + +void __show_regs(struct pt_regs *regs) +{ + unsigned long flags; + char buf[64]; + + printk(KERN_DEFAULT "CPU: %d %s (%s %.*s)\n", + raw_smp_processor_id(), print_tainted(), + init_utsname()->release, + (int)strcspn(init_utsname()->version, " "), + init_utsname()->version); + print_symbol("PC is at %s\n", instruction_pointer(regs)); + print_symbol("LR is at %s\n", regs->UCreg_lr); + printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n" + "sp : %08lx ip : %08lx fp : %08lx\n", + regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr, + regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp); + printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n", + regs->UCreg_26, regs->UCreg_25, + regs->UCreg_24); + printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n", + regs->UCreg_23, regs->UCreg_22, + regs->UCreg_21, regs->UCreg_20); + printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n", + regs->UCreg_19, regs->UCreg_18, + regs->UCreg_17, regs->UCreg_16); + printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n", + regs->UCreg_15, regs->UCreg_14, + regs->UCreg_13, regs->UCreg_12); + printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n", + regs->UCreg_11, regs->UCreg_10, + regs->UCreg_09, regs->UCreg_08); + printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", + regs->UCreg_07, regs->UCreg_06, + regs->UCreg_05, regs->UCreg_04); + printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", + regs->UCreg_03, regs->UCreg_02, + regs->UCreg_01, regs->UCreg_00); + + flags = regs->UCreg_asr; + buf[0] = flags & PSR_S_BIT ? 'S' : 's'; + buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z'; + buf[2] = flags & PSR_C_BIT ? 'C' : 'c'; + buf[3] = flags & PSR_V_BIT ? 'V' : 'v'; + buf[4] = '\0'; + + printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n", + buf, interrupts_enabled(regs) ? "n" : "ff", + fast_interrupts_enabled(regs) ? "n" : "ff", + processor_modes[processor_mode(regs)], + segment_eq(get_fs(), get_ds()) ? "kernel" : "user"); + { + unsigned int ctrl; + + buf[0] = '\0'; + { + unsigned int transbase; + asm("movc %0, p0.c2, #0\n" + : "=r" (transbase)); + snprintf(buf, sizeof(buf), " Table: %08x", transbase); + } + asm("movc %0, p0.c1, #0\n" : "=r" (ctrl)); + + printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf); + } +} + +void show_regs(struct pt_regs *regs) +{ + printk(KERN_DEFAULT "\n"); + printk(KERN_DEFAULT "Pid: %d, comm: %20s\n", + task_pid_nr(current), current->comm); + __show_regs(regs); + __backtrace(); +} + +/* + * Free current thread data structures etc.. + */ +void exit_thread(void) +{ +} + +void flush_thread(void) +{ + struct thread_info *thread = current_thread_info(); + struct task_struct *tsk = current; + + memset(thread->used_cp, 0, sizeof(thread->used_cp)); + memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); +#ifdef CONFIG_UNICORE_FPU_F64 + memset(&thread->fpstate, 0, sizeof(struct fp_state)); +#endif +} + +void release_thread(struct task_struct *dead_task) +{ +} + +asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); + +int +copy_thread(unsigned long clone_flags, unsigned long stack_start, + unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs) +{ + struct thread_info *thread = task_thread_info(p); + struct pt_regs *childregs = task_pt_regs(p); + + *childregs = *regs; + childregs->UCreg_00 = 0; + childregs->UCreg_sp = stack_start; + + memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); + thread->cpu_context.sp = (unsigned long)childregs; + thread->cpu_context.pc = (unsigned long)ret_from_fork; + + if (clone_flags & CLONE_SETTLS) + childregs->UCreg_16 = regs->UCreg_03; + + return 0; +} + +/* + * Fill in the task's elfregs structure for a core dump. + */ +int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs) +{ + elf_core_copy_regs(elfregs, task_pt_regs(t)); + return 1; +} + +/* + * fill in the fpe structure for a core dump... + */ +int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fp) +{ + struct thread_info *thread = current_thread_info(); + int used_math = thread->used_cp[1] | thread->used_cp[2]; + +#ifdef CONFIG_UNICORE_FPU_F64 + if (used_math) + memcpy(fp, &thread->fpstate, sizeof(*fp)); +#endif + return used_math != 0; +} +EXPORT_SYMBOL(dump_fpu); + +/* + * Shuffle the argument into the correct register before calling the + * thread function. r1 is the thread argument, r2 is the pointer to + * the thread function, and r3 points to the exit function. + */ +asm(".pushsection .text\n" +" .align\n" +" .type kernel_thread_helper, #function\n" +"kernel_thread_helper:\n" +" mov.a asr, r7\n" +" mov r0, r4\n" +" mov lr, r6\n" +" mov pc, r5\n" +" .size kernel_thread_helper, . - kernel_thread_helper\n" +" .popsection"); + +/* + * Create a kernel thread. + */ +pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) +{ + struct pt_regs regs; + + memset(®s, 0, sizeof(regs)); + + regs.UCreg_04 = (unsigned long)arg; + regs.UCreg_05 = (unsigned long)fn; + regs.UCreg_06 = (unsigned long)do_exit; + regs.UCreg_07 = PRIV_MODE; + regs.UCreg_pc = (unsigned long)kernel_thread_helper; + regs.UCreg_asr = regs.UCreg_07 | PSR_I_BIT; + + return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); +} +EXPORT_SYMBOL(kernel_thread); + +unsigned long get_wchan(struct task_struct *p) +{ + struct stackframe frame; + int count = 0; + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + + frame.fp = thread_saved_fp(p); + frame.sp = thread_saved_sp(p); + frame.lr = 0; /* recovered from the stack */ + frame.pc = thread_saved_pc(p); + do { + int ret = unwind_frame(&frame); + if (ret < 0) + return 0; + if (!in_sched_functions(frame.pc)) + return frame.pc; + } while ((count++) < 16); + return 0; +} + +unsigned long arch_randomize_brk(struct mm_struct *mm) +{ + unsigned long range_end = mm->brk + 0x02000000; + return randomize_range(mm->brk, range_end, 0) ? : mm->brk; +} + +/* + * The vectors page is always readable from user space for the + * atomic helpers and the signal restart code. Let's declare a mapping + * for it so it is visible through ptrace and /proc//mem. + */ + +int vectors_user_mapping(void) +{ + struct mm_struct *mm = current->mm; + return install_special_mapping(mm, 0xffff0000, PAGE_SIZE, + VM_READ | VM_EXEC | + VM_MAYREAD | VM_MAYEXEC | + VM_ALWAYSDUMP | VM_RESERVED, + NULL); +} + +const char *arch_vma_name(struct vm_area_struct *vma) +{ + return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL; +} diff --git a/arch/unicore32/kernel/stacktrace.c b/arch/unicore32/kernel/stacktrace.c new file mode 100644 index 000000000000..b34030bdabe3 --- /dev/null +++ b/arch/unicore32/kernel/stacktrace.c @@ -0,0 +1,131 @@ +/* + * linux/arch/unicore32/kernel/stacktrace.c + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include +#include +#include + +#include + +#if defined(CONFIG_FRAME_POINTER) +/* + * Unwind the current stack frame and store the new register values in the + * structure passed as argument. Unwinding is equivalent to a function return, + * hence the new PC value rather than LR should be used for backtrace. + * + * With framepointer enabled, a simple function prologue looks like this: + * mov ip, sp + * stmdb sp!, {fp, ip, lr, pc} + * sub fp, ip, #4 + * + * A simple function epilogue looks like this: + * ldm sp, {fp, sp, pc} + * + * Note that with framepointer enabled, even the leaf functions have the same + * prologue and epilogue, therefore we can ignore the LR value in this case. + */ +int notrace unwind_frame(struct stackframe *frame) +{ + unsigned long high, low; + unsigned long fp = frame->fp; + + /* only go to a higher address on the stack */ + low = frame->sp; + high = ALIGN(low, THREAD_SIZE); + + /* check current frame pointer is within bounds */ + if (fp < (low + 12) || fp + 4 >= high) + return -EINVAL; + + /* restore the registers from the stack frame */ + frame->fp = *(unsigned long *)(fp - 12); + frame->sp = *(unsigned long *)(fp - 8); + frame->pc = *(unsigned long *)(fp - 4); + + return 0; +} +#endif + +void notrace walk_stackframe(struct stackframe *frame, + int (*fn)(struct stackframe *, void *), void *data) +{ + while (1) { + int ret; + + if (fn(frame, data)) + break; + ret = unwind_frame(frame); + if (ret < 0) + break; + } +} +EXPORT_SYMBOL(walk_stackframe); + +#ifdef CONFIG_STACKTRACE +struct stack_trace_data { + struct stack_trace *trace; + unsigned int no_sched_functions; + unsigned int skip; +}; + +static int save_trace(struct stackframe *frame, void *d) +{ + struct stack_trace_data *data = d; + struct stack_trace *trace = data->trace; + unsigned long addr = frame->pc; + + if (data->no_sched_functions && in_sched_functions(addr)) + return 0; + if (data->skip) { + data->skip--; + return 0; + } + + trace->entries[trace->nr_entries++] = addr; + + return trace->nr_entries >= trace->max_entries; +} + +void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) +{ + struct stack_trace_data data; + struct stackframe frame; + + data.trace = trace; + data.skip = trace->skip; + + if (tsk != current) { + data.no_sched_functions = 1; + frame.fp = thread_saved_fp(tsk); + frame.sp = thread_saved_sp(tsk); + frame.lr = 0; /* recovered from the stack */ + frame.pc = thread_saved_pc(tsk); + } else { + register unsigned long current_sp asm("sp"); + + data.no_sched_functions = 0; + frame.fp = (unsigned long)__builtin_frame_address(0); + frame.sp = current_sp; + frame.lr = (unsigned long)__builtin_return_address(0); + frame.pc = (unsigned long)save_stack_trace_tsk; + } + + walk_stackframe(&frame, save_trace, &data); + if (trace->nr_entries < trace->max_entries) + trace->entries[trace->nr_entries++] = ULONG_MAX; +} + +void save_stack_trace(struct stack_trace *trace) +{ + save_stack_trace_tsk(current, trace); +} +EXPORT_SYMBOL_GPL(save_stack_trace); +#endif diff --git a/arch/unicore32/lib/backtrace.S b/arch/unicore32/lib/backtrace.S new file mode 100644 index 000000000000..ef01d77f2f65 --- /dev/null +++ b/arch/unicore32/lib/backtrace.S @@ -0,0 +1,163 @@ +/* + * linux/arch/unicore32/lib/backtrace.S + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include +#include + .text + +@ fp is 0 or stack frame + +#define frame v4 +#define sv_fp v5 +#define sv_pc v6 +#define offset v8 + +ENTRY(__backtrace) + mov r0, fp + +ENTRY(c_backtrace) + +#if !defined(CONFIG_FRAME_POINTER) || !defined(CONFIG_PRINTK) + mov pc, lr +ENDPROC(__backtrace) +ENDPROC(c_backtrace) +#else + stm.w (v4 - v8, lr), [sp-] @ Save an extra register + @ so we have a location... + mov.a frame, r0 @ if frame pointer is zero + beq no_frame @ we have no stack frames + +1: stm.w (pc), [sp-] @ calculate offset of PC stored + ldw.w r0, [sp]+, #4 @ by stmfd for this CPU + adr r1, 1b + sub offset, r0, r1 + +/* + * Stack frame layout: + * optionally saved caller registers (r4 - r10) + * saved fp + * saved sp + * saved lr + * frame => saved pc + * optionally saved arguments (r0 - r3) + * saved sp => + * + * Functions start with the following code sequence: + * mov ip, sp + * stm.w (r0 - r3), [sp-] (optional) + * corrected pc => stm.w sp, (..., fp, ip, lr, pc) + */ +for_each_frame: + +1001: ldw sv_pc, [frame+], #0 @ get saved pc +1002: ldw sv_fp, [frame+], #-12 @ get saved fp + + sub sv_pc, sv_pc, offset @ Correct PC for prefetching + +1003: ldw r2, [sv_pc+], #-4 @ if stmfd sp, {args} exists, + ldw r3, .Ldsi+4 @ adjust saved 'pc' back one + cxor.a r3, r2 >> #14 @ instruction + beq 201f + sub r0, sv_pc, #4 @ allow for mov + b 202f +201: + sub r0, sv_pc, #8 @ allow for mov + stmia +202: + ldw r1, [frame+], #-4 @ get saved lr + mov r2, frame + b.l dump_backtrace_entry + + ldw r1, [sv_pc+], #-4 @ if stmfd sp, {args} exists, + ldw r3, .Ldsi+4 + cxor.a r3, r1 >> #14 + bne 1004f + ldw r0, [frame+], #-8 @ get sp + sub r0, r0, #4 @ point at the last arg + b.l .Ldumpstm @ dump saved registers + +1004: ldw r1, [sv_pc+], #0 @ if stmfd {, fp, ip, lr, pc} + ldw r3, .Ldsi @ instruction exists, + cxor.a r3, r1 >> #14 + bne 201f + sub r0, frame, #16 + b.l .Ldumpstm @ dump saved registers +201: + cxor.a sv_fp, #0 @ zero saved fp means + beq no_frame @ no further frames + + csub.a sv_fp, frame @ next frame must be + mov frame, sv_fp @ above the current frame + bua for_each_frame + +1006: adr r0, .Lbad + mov r1, frame + b.l printk +no_frame: ldm.w (v4 - v8, pc), [sp]+ +ENDPROC(__backtrace) +ENDPROC(c_backtrace) + + .pushsection __ex_table,"a" + .align 3 + .long 1001b, 1006b + .long 1002b, 1006b + .long 1003b, 1006b + .long 1004b, 1006b + .popsection + +#define instr v4 +#define reg v5 +#define stack v6 + +.Ldumpstm: stm.w (instr, reg, stack, v7, lr), [sp-] + mov stack, r0 + mov instr, r1 + mov reg, #14 + mov v7, #0 +1: mov r3, #1 + csub.a reg, #8 + bne 201f + sub reg, reg, #3 +201: + cand.a instr, r3 << reg + beq 2f + add v7, v7, #1 + cxor.a v7, #6 + cmoveq v7, #1 + cmoveq r1, #'\n' + cmovne r1, #' ' + ldw.w r3, [stack]+, #-4 + mov r2, reg + csub.a r2, #8 + bsl 201f + sub r2, r2, #3 +201: + cand.a instr, #0x40 @ if H is 1, high 16 regs + beq 201f + add r2, r2, #0x10 @ so r2 need add 16 +201: + adr r0, .Lfp + b.l printk +2: sub.a reg, reg, #1 + bns 1b + cxor.a v7, #0 + beq 201f + adr r0, .Lcr + b.l printk +201: ldm.w (instr, reg, stack, v7, pc), [sp]+ + +.Lfp: .asciz "%cr%d:%08x" +.Lcr: .asciz "\n" +.Lbad: .asciz "Backtrace aborted due to bad frame pointer <%p>\n" + .align +.Ldsi: .word 0x92eec000 >> 14 @ stm.w sp, (... fp, ip, lr, pc) + .word 0x92e10000 >> 14 @ stm.w sp, () + +#endif