|  | /* | 
|  | * 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, | 
|  | void __user *parent_tidptr, void __user *child_tidptr, | 
|  | struct pt_regs *regs) | 
|  | { | 
|  | if (!newsp) | 
|  | newsp = regs->sp; | 
|  | return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, | 
|  | 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, | 
|  | const char __user *const __user *uargv, | 
|  | const char __user *const __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; | 
|  | } |