2 * Copyright (C) 2004-2006 Atmel Corporation
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 #include <linux/sched.h>
9 #include <linux/sched/debug.h>
10 #include <linux/sched/task.h>
11 #include <linux/module.h>
12 #include <linux/kallsyms.h>
15 #include <linux/ptrace.h>
16 #include <linux/slab.h>
17 #include <linux/reboot.h>
18 #include <linux/tick.h>
19 #include <linux/uaccess.h>
20 #include <linux/unistd.h>
22 #include <asm/sysreg.h>
24 #include <asm/syscalls.h>
28 void (*pm_power_off)(void);
29 EXPORT_SYMBOL(pm_power_off);
32 * This file handles the architecture-dependent parts of process handling..
35 void arch_cpu_idle(void)
40 void machine_halt(void)
43 * Enter Stop mode. The 32 kHz oscillator will keep running so
44 * the RTC will keep the time properly and the system will
47 asm volatile("sleep 3\n\t"
51 void machine_power_off(void)
57 void machine_restart(char *cmd)
59 ocd_write(DC, (1 << OCD_DC_DBE_BIT));
60 ocd_write(DC, (1 << OCD_DC_RES_BIT));
65 * Free current thread data structures etc
67 void exit_thread(struct task_struct *tsk)
72 void flush_thread(void)
77 void release_thread(struct task_struct *dead_task)
82 static void dump_mem(const char *str, const char *log_lvl,
83 unsigned long bottom, unsigned long top)
88 printk("%s%s(0x%08lx to 0x%08lx)\n", log_lvl, str, bottom, top);
90 for (p = bottom & ~31; p < top; ) {
91 printk("%s%04lx: ", log_lvl, p & 0xffff);
93 for (i = 0; i < 8; i++, p += 4) {
96 if (p < bottom || p >= top)
99 if (__get_user(val, (unsigned int __user *)p)) {
103 printk("%08x ", val);
113 static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p)
115 return (p > (unsigned long)tinfo)
116 && (p < (unsigned long)tinfo + THREAD_SIZE - 3);
119 #ifdef CONFIG_FRAME_POINTER
120 static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
121 struct pt_regs *regs, const char *log_lvl)
123 unsigned long lr, fp;
124 struct thread_info *tinfo;
128 else if (tsk == current)
129 asm("mov %0, r7" : "=r"(fp));
131 fp = tsk->thread.cpu_context.r7;
134 * Walk the stack as long as the frame pointer (a) is within
135 * the kernel stack of the task, and (b) it doesn't move
138 tinfo = task_thread_info(tsk);
139 printk("%sCall trace:\n", log_lvl);
140 while (valid_stack_ptr(tinfo, fp)) {
141 unsigned long new_fp;
143 lr = *(unsigned long *)fp;
144 #ifdef CONFIG_KALLSYMS
145 printk("%s [<%08lx>] ", log_lvl, lr);
147 printk(" [<%08lx>] ", lr);
149 print_symbol("%s\n", lr);
151 new_fp = *(unsigned long *)(fp + 4);
159 static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp,
160 struct pt_regs *regs, const char *log_lvl)
164 printk("%sCall trace:\n", log_lvl);
166 while (!kstack_end(sp)) {
168 if (kernel_text_address(addr)) {
169 #ifdef CONFIG_KALLSYMS
170 printk("%s [<%08lx>] ", log_lvl, addr);
172 printk(" [<%08lx>] ", addr);
174 print_symbol("%s\n", addr);
181 void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp,
182 struct pt_regs *regs, const char *log_lvl)
184 struct thread_info *tinfo;
188 sp = tsk->thread.cpu_context.ksp;
190 sp = (unsigned long)&tinfo;
195 tinfo = task_thread_info(tsk);
197 if (valid_stack_ptr(tinfo, sp)) {
198 dump_mem("Stack: ", log_lvl, sp,
199 THREAD_SIZE + (unsigned long)tinfo);
200 show_trace_log_lvl(tsk, (unsigned long *)sp, regs, log_lvl);
204 void show_stack(struct task_struct *tsk, unsigned long *stack)
206 show_stack_log_lvl(tsk, (unsigned long)stack, NULL, "");
209 static const char *cpu_modes[] = {
210 "Application", "Supervisor", "Interrupt level 0", "Interrupt level 1",
211 "Interrupt level 2", "Interrupt level 3", "Exception", "NMI"
214 void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl)
216 unsigned long sp = regs->sp;
217 unsigned long lr = regs->lr;
218 unsigned long mode = (regs->sr & MODE_MASK) >> MODE_SHIFT;
220 show_regs_print_info(log_lvl);
222 if (!user_mode(regs)) {
223 sp = (unsigned long)regs + FRAME_SIZE_FULL;
225 printk("%s", log_lvl);
226 print_symbol("PC is at %s\n", instruction_pointer(regs));
227 printk("%s", log_lvl);
228 print_symbol("LR is at %s\n", lr);
231 printk("%spc : [<%08lx>] lr : [<%08lx>] %s\n"
232 "%ssp : %08lx r12: %08lx r11: %08lx\n",
233 log_lvl, instruction_pointer(regs), lr, print_tainted(),
234 log_lvl, sp, regs->r12, regs->r11);
235 printk("%sr10: %08lx r9 : %08lx r8 : %08lx\n",
236 log_lvl, regs->r10, regs->r9, regs->r8);
237 printk("%sr7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
238 log_lvl, regs->r7, regs->r6, regs->r5, regs->r4);
239 printk("%sr3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
240 log_lvl, regs->r3, regs->r2, regs->r1, regs->r0);
241 printk("%sFlags: %c%c%c%c%c\n", log_lvl,
242 regs->sr & SR_Q ? 'Q' : 'q',
243 regs->sr & SR_V ? 'V' : 'v',
244 regs->sr & SR_N ? 'N' : 'n',
245 regs->sr & SR_Z ? 'Z' : 'z',
246 regs->sr & SR_C ? 'C' : 'c');
247 printk("%sMode bits: %c%c%c%c%c%c%c%c%c%c\n", log_lvl,
248 regs->sr & SR_H ? 'H' : 'h',
249 regs->sr & SR_J ? 'J' : 'j',
250 regs->sr & SR_DM ? 'M' : 'm',
251 regs->sr & SR_D ? 'D' : 'd',
252 regs->sr & SR_EM ? 'E' : 'e',
253 regs->sr & SR_I3M ? '3' : '.',
254 regs->sr & SR_I2M ? '2' : '.',
255 regs->sr & SR_I1M ? '1' : '.',
256 regs->sr & SR_I0M ? '0' : '.',
257 regs->sr & SR_GM ? 'G' : 'g');
258 printk("%sCPU Mode: %s\n", log_lvl, cpu_modes[mode]);
261 void show_regs(struct pt_regs *regs)
263 unsigned long sp = regs->sp;
265 if (!user_mode(regs))
266 sp = (unsigned long)regs + FRAME_SIZE_FULL;
268 show_regs_log_lvl(regs, "");
269 show_trace_log_lvl(current, (unsigned long *)sp, regs, "");
271 EXPORT_SYMBOL(show_regs);
273 /* Fill in the fpu structure for a core dump. This is easy -- we don't have any */
274 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
280 asmlinkage void ret_from_fork(void);
281 asmlinkage void ret_from_kernel_thread(void);
282 asmlinkage void syscall_return(void);
284 int copy_thread(unsigned long clone_flags, unsigned long usp,
286 struct task_struct *p)
288 struct pt_regs *childregs = task_pt_regs(p);
290 if (unlikely(p->flags & PF_KTHREAD)) {
291 memset(childregs, 0, sizeof(struct pt_regs));
292 p->thread.cpu_context.r0 = arg;
293 p->thread.cpu_context.r1 = usp; /* fn */
294 p->thread.cpu_context.r2 = (unsigned long)syscall_return;
295 p->thread.cpu_context.pc = (unsigned long)ret_from_kernel_thread;
296 childregs->sr = MODE_SUPERVISOR;
298 *childregs = *current_pt_regs();
301 childregs->r12 = 0; /* Set return value for child */
302 p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
305 p->thread.cpu_context.sr = MODE_SUPERVISOR | SR_GM;
306 p->thread.cpu_context.ksp = (unsigned long)childregs;
308 clear_tsk_thread_flag(p, TIF_DEBUG);
309 if ((clone_flags & CLONE_PTRACE) && test_thread_flag(TIF_DEBUG))
316 * This function is supposed to answer the question "who called
319 unsigned long get_wchan(struct task_struct *p)
322 unsigned long stack_page;
324 if (!p || p == current || p->state == TASK_RUNNING)
327 stack_page = (unsigned long)task_stack_page(p);
331 * The stored value of PC is either the address right after
332 * the call to __switch_to() or ret_from_fork.
334 pc = thread_saved_pc(p);
335 if (in_sched_functions(pc)) {
336 #ifdef CONFIG_FRAME_POINTER
337 unsigned long fp = p->thread.cpu_context.r7;
338 BUG_ON(fp < stack_page || fp > (THREAD_SIZE + stack_page));
339 pc = *(unsigned long *)fp;
342 * We depend on the frame size of schedule here, which
343 * is actually quite ugly. It might be possible to
344 * determine the frame size automatically at build
345 * time by doing this:
346 * - compile sched/core.c
347 * - disassemble the resulting sched.o
348 * - look for 'sub sp,??' shortly after '<schedule>:'
350 unsigned long sp = p->thread.cpu_context.ksp + 16;
351 BUG_ON(sp < stack_page || sp > (THREAD_SIZE + stack_page));
352 pc = *(unsigned long *)sp;