| /* |
| * 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; |
| |
| printk("%s", log_lvl); |
| print_symbol("PC is at %s\n", instruction_pointer(regs)); |
| printk("%s", log_lvl); |
| print_symbol("LR is at %s\n", lr); |
| } |
| |
| printk("%spc : [<%08lx>] lr : [<%08lx>] %s\n" |
| "%ssp : %08lx r12: %08lx r11: %08lx\n", |
| log_lvl, instruction_pointer(regs), lr, print_tainted(), |
| log_lvl, sp, regs->r12, regs->r11); |
| printk("%sr10: %08lx r9 : %08lx r8 : %08lx\n", |
| log_lvl, regs->r10, regs->r9, regs->r8); |
| printk("%sr7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", |
| log_lvl, regs->r7, regs->r6, regs->r5, regs->r4); |
| printk("%sr3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", |
| log_lvl, regs->r3, regs->r2, regs->r1, regs->r0); |
| printk("%sFlags: %c%c%c%c%c\n", log_lvl, |
| regs->sr & SR_Q ? 'Q' : 'q', |
| regs->sr & SR_V ? 'V' : 'v', |
| regs->sr & SR_N ? 'N' : 'n', |
| regs->sr & SR_Z ? 'Z' : 'z', |
| regs->sr & SR_C ? 'C' : 'c'); |
| printk("%sMode bits: %c%c%c%c%c%c%c%c%c%c\n", log_lvl, |
| regs->sr & SR_H ? 'H' : 'h', |
| regs->sr & SR_J ? 'J' : 'j', |
| regs->sr & SR_DM ? 'M' : 'm', |
| regs->sr & SR_D ? 'D' : 'd', |
| regs->sr & SR_EM ? 'E' : 'e', |
| regs->sr & SR_I3M ? '3' : '.', |
| regs->sr & SR_I2M ? '2' : '.', |
| regs->sr & SR_I1M ? '1' : '.', |
| regs->sr & SR_I0M ? '0' : '.', |
| regs->sr & SR_GM ? 'G' : 'g'); |
| printk("%sCPU Mode: %s\n", log_lvl, cpu_modes[mode]); |
| printk("%sProcess: %s [%d] (task: %p thread: %p)\n", |
| log_lvl, current->comm, current->pid, current, |
| task_thread_info(current)); |
| } |
| |
| void show_regs(struct pt_regs *regs) |
| { |
| unsigned long sp = regs->sp; |
| |
| if (!user_mode(regs)) |
| sp = (unsigned long)regs + FRAME_SIZE_FULL; |
| |
| show_regs_log_lvl(regs, ""); |
| show_trace_log_lvl(current, (unsigned long *)sp, regs, ""); |
| } |
| EXPORT_SYMBOL(show_regs); |
| |
| /* Fill in the fpu structure for a core dump. This is easy -- we don't have any */ |
| int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) |
| { |
| /* Not valid */ |
| return 0; |
| } |
| |
| asmlinkage void ret_from_fork(void); |
| |
| int copy_thread(unsigned long clone_flags, unsigned long usp, |
| unsigned long unused, |
| struct task_struct *p, struct pt_regs *regs) |
| { |
| struct pt_regs *childregs; |
| |
| childregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long)task_stack_page(p))) - 1; |
| *childregs = *regs; |
| |
| if (user_mode(regs)) |
| childregs->sp = usp; |
| else |
| childregs->sp = (unsigned long)task_stack_page(p) + THREAD_SIZE; |
| |
| childregs->r12 = 0; /* Set return value for child */ |
| |
| p->thread.cpu_context.sr = MODE_SUPERVISOR | SR_GM; |
| p->thread.cpu_context.ksp = (unsigned long)childregs; |
| p->thread.cpu_context.pc = (unsigned long)ret_from_fork; |
| |
| clear_tsk_thread_flag(p, TIF_DEBUG); |
| if ((clone_flags & CLONE_PTRACE) && test_thread_flag(TIF_DEBUG)) |
| ocd_enable(p); |
| |
| return 0; |
| } |
| |
| /* r12-r8 are dummy parameters to force the compiler to use the stack */ |
| asmlinkage int sys_fork(struct pt_regs *regs) |
| { |
| return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL); |
| } |
| |
| asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, |
| unsigned long parent_tidptr, |
| unsigned long child_tidptr, struct pt_regs *regs) |
| { |
| if (!newsp) |
| newsp = regs->sp; |
| return do_fork(clone_flags, newsp, regs, 0, |
| (int __user *)parent_tidptr, |
| (int __user *)child_tidptr); |
| } |
| |
| asmlinkage int sys_vfork(struct pt_regs *regs) |
| { |
| return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, |
| 0, NULL, NULL); |
| } |
| |
| asmlinkage int sys_execve(const char __user *ufilename, |
| char __user *__user *uargv, |
| char __user *__user *uenvp, struct pt_regs *regs) |
| { |
| int error; |
| char *filename; |
| |
| filename = getname(ufilename); |
| error = PTR_ERR(filename); |
| if (IS_ERR(filename)) |
| goto out; |
| |
| error = do_execve(filename, uargv, uenvp, regs); |
| putname(filename); |
| |
| out: |
| return error; |
| } |
| |
| |
| /* |
| * This function is supposed to answer the question "who called |
| * schedule()?" |
| */ |
| unsigned long get_wchan(struct task_struct *p) |
| { |
| unsigned long pc; |
| unsigned long stack_page; |
| |
| if (!p || p == current || p->state == TASK_RUNNING) |
| return 0; |
| |
| stack_page = (unsigned long)task_stack_page(p); |
| BUG_ON(!stack_page); |
| |
| /* |
| * The stored value of PC is either the address right after |
| * the call to __switch_to() or ret_from_fork. |
| */ |
| pc = thread_saved_pc(p); |
| if (in_sched_functions(pc)) { |
| #ifdef CONFIG_FRAME_POINTER |
| unsigned long fp = p->thread.cpu_context.r7; |
| BUG_ON(fp < stack_page || fp > (THREAD_SIZE + stack_page)); |
| pc = *(unsigned long *)fp; |
| #else |
| /* |
| * We depend on the frame size of schedule here, which |
| * is actually quite ugly. It might be possible to |
| * determine the frame size automatically at build |
| * time by doing this: |
| * - compile sched.c |
| * - disassemble the resulting sched.o |
| * - look for 'sub sp,??' shortly after '<schedule>:' |
| */ |
| unsigned long sp = p->thread.cpu_context.ksp + 16; |
| BUG_ON(sp < stack_page || sp > (THREAD_SIZE + stack_page)); |
| pc = *(unsigned long *)sp; |
| #endif |
| } |
| |
| return pc; |
| } |