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/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* 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 <linux/sched.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/fs.h>
#include <linux/pm.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/reboot.h>
#include <linux/tick.h>
#include <linux/uaccess.h>
#include <linux/unistd.h>
#include <asm/sysreg.h>
#include <asm/ocd.h>
#include <asm/syscalls.h>
#include <mach/pm.h>
void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);
/*
* This file handles the architecture-dependent parts of process handling..
*/
void cpu_idle(void)
{
/* endless idle loop with no priority at all */
while (1) {
tick_nohz_stop_sched_tick(1);
while (!need_resched())
cpu_idle_sleep();
tick_nohz_restart_sched_tick();
preempt_enable_no_resched();
schedule();
preempt_disable();
}
}
void machine_halt(void)
{
/*
* Enter Stop mode. The 32 kHz oscillator will keep running so
* the RTC will keep the time properly and the system will
* boot quickly.
*/
asm volatile("sleep 3\n\t"
"sub pc, -2");
}
void machine_power_off(void)
{
if (pm_power_off)
pm_power_off();
}
void machine_restart(char *cmd)
{
ocd_write(DC, (1 << OCD_DC_DBE_BIT));
ocd_write(DC, (1 << OCD_DC_RES_BIT));
while (1) ;
}
/*
* PC is actually discarded when returning from a system call -- the
* return address must be stored in LR. This function will make sure
* LR points to do_exit before starting the thread.
*
* Also, when returning from fork(), r12 is 0, so we must copy the
* argument as well.
*
* r0 : The argument to the main thread function
* r1 : The address of do_exit
* r2 : The address of the main thread function
*/
asmlinkage extern void kernel_thread_helper(void);
__asm__(" .type kernel_thread_helper, @function\n"
"kernel_thread_helper:\n"
" mov r12, r0\n"
" mov lr, r2\n"
" mov pc, r1\n"
" .size kernel_thread_helper, . - kernel_thread_helper");
int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
{
struct pt_regs regs;
memset(®s, 0, sizeof(regs));
regs.r0 = (unsigned long)arg;
regs.r1 = (unsigned long)fn;
regs.r2 = (unsigned long)do_exit;
regs.lr = (unsigned long)kernel_thread_helper;
regs.pc = (unsigned long)kernel_thread_helper;
regs.sr = MODE_SUPERVISOR;
return do_fork(flags | CLONE_VM | CLONE_UNTRACED,
0, ®s, 0, NULL, NULL);
}
EXPORT_SYMBOL(kernel_thread);
/*
* Free current thread data structures etc
*/
void exit_thread(void)
{
ocd_disable(current);
}
void flush_thread(void)
{
/* nothing to do */
}
void release_thread(struct task_struct *dead_task)
{
/* do nothing */
}
static void dump_mem(const char *str, const char *log_lvl,
unsigned long bottom, unsigned long top)
{
unsigned long p;
int i;
printk("%s%s(0x%08lx to 0x%08lx)\n", log_lvl, str, bottom, top);
for (p = bottom & ~31; p < top; ) {
printk("%s%04lx: ", log_lvl, p & 0xffff);
for (i = 0; i < 8; i++, p += 4) {
unsigned int val;
if (p < bottom || p >= top)
printk(" ");
else {
if (__get_user(val, (unsigned int __user *)p)) {
printk("\n");
goto out;
}
printk("%08x ", val);
}
}
printk("\n");
}
out:
return;
}
static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p)
{
return (p > (unsigned long)tinfo)
&& (p < (unsigned long)tinfo + THREAD_SIZE - 3);
}
#ifdef CONFIG_FRAME_POINTER
static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
struct pt_regs *regs, const char *log_lvl)
{
unsigned long lr, fp;
struct thread_info *tinfo;
if (regs)
fp = regs->r7;
else if (tsk == current)
asm("mov %0, r7" : "=r"(fp));
else
fp = tsk->thread.cpu_context.r7;
/*
* Walk the stack as long as the frame pointer (a) is within
* the kernel stack of the task, and (b) it doesn't move
* downwards.
*/
tinfo = task_thread_info(tsk);
printk("%sCall trace:\n", log_lvl);
while (valid_stack_ptr(tinfo, fp)) {
unsigned long new_fp;
lr = *(unsigned long *)fp;
#ifdef CONFIG_KALLSYMS
printk("%s [<%08lx>] ", log_lvl, lr);
#else
printk(" [<%08lx>] ", lr);
#endif
print_symbol("%s\n", lr);
new_fp = *(unsigned long *)(fp + 4);
if (new_fp <= fp)
break;
fp = new_fp;
}
printk("\n");
}
#else
static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
struct pt_regs *regs, const char *log_lvl)
{
unsigned long addr;
printk("%sCall trace:\n", log_lvl);
while (!kstack_end(sp)) {
addr = *sp++;
if (kernel_text_address(addr)) {
#ifdef CONFIG_KALLSYMS
printk("%s [<%08lx>] ", log_lvl, addr);
#else
printk(" [<%08lx>] ", addr);
#endif
print_symbol("%s\n", addr);
}
}
printk("\n");
}
#endif
void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp,
struct pt_regs *regs, const char *log_lvl)
{
struct thread_info *tinfo;
if (sp == 0) {
if (tsk)
sp = tsk->thread.cpu_context.ksp;
else
sp = (unsigned long)&tinfo;
}
if (!tsk)
tsk = current;
tinfo = task_thread_info(tsk);
if (valid_stack_ptr(tinfo, sp)) {
dump_mem("Stack: ", log_lvl, sp,
THREAD_SIZE + (unsigned long)tinfo);
show_trace_log_lvl(tsk, (unsigned long *)sp, regs, log_lvl);
}
}
void show_stack(struct task_struct *tsk, unsigned long *stack)
{
show_stack_log_lvl(tsk, (unsigned long)stack, NULL, "");
}
void dump_stack(void)
{
unsigned long stack;
show_trace_log_lvl(current, &stack, NULL, "");
}
EXPORT_SYMBOL(dump_stack);
static const char *cpu_modes[] = {
"Application", "Supervisor", "Interrupt level 0", "Interrupt level 1",
"Interrupt level 2", "Interrupt level 3", "Exception", "NMI"
};
void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl)
{
unsigned long sp = regs->sp;
unsigned long lr = regs->lr;
unsigned long mode = (regs->sr & MODE_MASK) >> MODE_SHIFT;
if (!user_mode(regs)) {
sp = (unsigned long)regs + FRAME_SIZE_FULL;
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