/* *  linux/arch/arm/kernel/process.c * *  Copyright (C) 1996-2000 Russell King - Converted to ARM. *  Original Copyright (C) 1995  Linus Torvalds * * 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 <stdarg.h> #include <linux/module.h>#include <linux/sched.h>#include <linux/kernel.h>#include <linux/mm.h>#include <linux/stddef.h>#include <linux/unistd.h>#include <linux/ptrace.h>#include <linux/slab.h>#include <linux/user.h>#include <linux/a.out.h>#include <linux/delay.h>#include <linux/reboot.h>#include <linux/interrupt.h>#include <linux/kallsyms.h>#include <linux/init.h>#include <linux/cpu.h>#include <linux/elfcore.h>#include <linux/pm.h> #include <asm/leds.h>#include <asm/processor.h>#include <asm/system.h>#include <asm/thread_notify.h>#include <asm/uaccess.h>#include <asm/mach/time.h> static const char *processor_modes[] = {  "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,  "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",  "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,  "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"}; extern void setup_mm_for_reboot(char mode); static volatile int hlt_counter; #include <asm/arch/system.h> void disable_hlt(void){	hlt_counter++;} EXPORT_SYMBOL(disable_hlt); void enable_hlt(void){	hlt_counter--;} EXPORT_SYMBOL(enable_hlt); static int __init nohlt_setup(char *__unused){	hlt_counter = 1;	return 1;} static int __init hlt_setup(char *__unused){	hlt_counter = 0;	return 1;} __setup("nohlt", nohlt_setup);__setup("hlt", hlt_setup); void arm_machine_restart(char mode){	/*	 * Clean and disable cache, and turn off interrupts	 */	cpu_proc_fin(); 	/*	 * 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(mode); 	/*	 * Now call the architecture specific reboot code.	 */	arch_reset(mode); 	/*	 * Whoops - the architecture was unable to reboot.	 * Tell the user!	 */	mdelay(1000);	printk("Reboot failed -- System halted\n");	while (1);} /* * Function pointers to optional machine specific functions */void (*pm_idle)(void);EXPORT_SYMBOL(pm_idle); void (*pm_power_off)(void);EXPORT_SYMBOL(pm_power_off); void (*arm_pm_restart)(char str) = arm_machine_restart;EXPORT_SYMBOL_GPL(arm_pm_restart);  /* * This is our default idle handler.  We need to disable * interrupts here to ensure we don't miss a wakeup call. */static void default_idle(void){	if (hlt_counter)		cpu_relax();	else {		local_irq_disable();		if (!need_resched()) {			timer_dyn_reprogram();			arch_idle();		}		local_irq_enable();	}} /* * The idle thread.  We try to conserve power, while trying to keep * overall latency low.  The architecture specific idle is passed * a value to indicate the level of "idleness" of the system. */void cpu_idle(void){	local_fiq_enable(); 	/* endless idle loop with no priority at all */	while (1) {		void (*idle)(void) = pm_idle; #ifdef CONFIG_HOTPLUG_CPU		if (cpu_is_offline(smp_processor_id())) {			leds_event(led_idle_start);			cpu_die();		}#endif 		if (!idle)			idle = default_idle;		leds_event(led_idle_start);		while (!need_resched())			idle();		leds_event(led_idle_end);		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){}  void machine_power_off(void){	if (pm_power_off)		pm_power_off();} void machine_restart(char * __unused){	arm_pm_restart(reboot_mode);} void __show_regs(struct pt_regs *regs){	unsigned long flags = condition_codes(regs); 	printk("CPU: %d\n", smp_processor_id());	print_symbol("PC is at %s\n", instruction_pointer(regs));	print_symbol("LR is at %s\n", regs->ARM_lr);	printk("pc : [<%08lx>]    lr : [<%08lx>]    %s\n"	       "sp : %08lx  ip : %08lx  fp : %08lx\n",		instruction_pointer(regs),		regs->ARM_lr, print_tainted(), regs->ARM_sp,		regs->ARM_ip, regs->ARM_fp);	printk("r10: %08lx  r9 : %08lx  r8 : %08lx\n",		regs->ARM_r10, regs->ARM_r9,		regs->ARM_r8);	printk("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",		regs->ARM_r7, regs->ARM_r6,		regs->ARM_r5, regs->ARM_r4);	printk("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",		regs->ARM_r3, regs->ARM_r2,		regs->ARM_r1, regs->ARM_r0);	printk("Flags: %c%c%c%c",		flags & PSR_N_BIT ? 'N' : 'n',		flags & PSR_Z_BIT ? 'Z' : 'z',		flags & PSR_C_BIT ? 'C' : 'c',		flags & PSR_V_BIT ? 'V' : 'v');	printk("  IRQs o%s  FIQs o%s  Mode %s%s  Segment %s\n",		interrupts_enabled(regs) ? "n" : "ff",		fast_interrupts_enabled(regs) ? "n" : "ff",		processor_modes[processor_mode(regs)],		thumb_mode(regs) ? " (T)" : "",		get_fs() == get_ds() ? "kernel" : "user");#if CONFIG_CPU_CP15	{		unsigned int ctrl;		  __asm__ (		"	mrc p15, 0, %0, c1, c0\n"		: "=r" (ctrl));		printk("Control: %04X\n", ctrl);	}#ifdef CONFIG_CPU_CP15_MMU	{		unsigned int transbase, dac;		  __asm__ (		"	mrc p15, 0, %0, c2, c0\n"		"	mrc p15, 0, %1, c3, c0\n"		: "=r" (transbase), "=r" (dac));		printk("Table: %08X  DAC: %08X\n",		  	transbase, dac);	}#endif#endif} void show_regs(struct pt_regs * regs){	printk("\n");	printk("Pid: %d, comm: %20s\n", current->pid, current->comm);	__show_regs(regs);	__backtrace();} void show_fpregs(struct user_fp *regs){	int i; 	for (i = 0; i < 8; i++) {		unsigned long *p;		char type; 		p = (unsigned long *)(regs->fpregs + i); 		switch (regs->ftype[i]) {			case 1: type = 'f'; break;			case 2: type = 'd'; break;			case 3: type = 'e'; break;			default: type = '?'; break;		}		if (regs->init_flag)			type = '?'; 		printk("  f%d(%c): %08lx %08lx %08lx%c",			i, type, p[0], p[1], p[2], i & 1 ? '\n' : ' ');	}			 	printk("FPSR: %08lx FPCR: %08lx\n",		(unsigned long)regs->fpsr,		(unsigned long)regs->fpcr);} /* * Free current thread data structures etc.. */void exit_thread(void){} ATOMIC_NOTIFIER_HEAD(thread_notify_head); EXPORT_SYMBOL_GPL(thread_notify_head); 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));	memset(&thread->fpstate, 0, sizeof(union fp_state)); 	thread_notify(THREAD_NOTIFY_FLUSH, thread);} void release_thread(struct task_struct *dead_task){	struct thread_info *thread = task_thread_info(dead_task); 	thread_notify(THREAD_NOTIFY_RELEASE, thread);} asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); intcopy_thread(int nr, 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->ARM_r0 = 0;	childregs->ARM_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)		thread->tp_value = regs->ARM_r3; 	return 0;} /* * fill in the fpe structure for a core dump... */int dump_fpu (struct pt_regs *regs, struct user_fp *fp){	struct thread_info *thread = current_thread_info();	int used_math = thread->used_cp[1] | thread->used_cp[2]; 	if (used_math)		memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); 	return used_math != 0;}EXPORT_SYMBOL(dump_fpu); /* * fill in the user structure for a core dump.. */void dump_thread(struct pt_regs * regs, struct user * dump){	struct task_struct *tsk = current; 	dump->magic = CMAGIC;	dump->start_code = tsk->mm->start_code;	dump->start_stack = regs->ARM_sp & ~(PAGE_SIZE - 1); 	dump->u_tsize = (tsk->mm->end_code - tsk->mm->start_code) >> PAGE_SHIFT;	dump->u_dsize = (tsk->mm->brk - tsk->mm->start_data + PAGE_SIZE - 1) >> PAGE_SHIFT;	dump->u_ssize = 0; 	dump->u_debugreg[0] = tsk->thread.debug.bp[0].address;	dump->u_debugreg[1] = tsk->thread.debug.bp[1].address;	dump->u_debugreg[2] = tsk->thread.debug.bp[0].insn.arm;	dump->u_debugreg[3] = tsk->thread.debug.bp[1].insn.arm;	dump->u_debugreg[4] = tsk->thread.debug.nsaved; 	if (dump->start_stack < 0x04000000)		dump->u_ssize = (0x04000000 - dump->start_stack) >> PAGE_SHIFT; 	dump->regs = *regs;	dump->u_fpvalid = dump_fpu (regs, &dump->u_fp);}EXPORT_SYMBOL(dump_thread); /* * 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. */extern void kernel_thread_helper(void);asm(	".section .text\n""	.align\n""	.type	kernel_thread_helper, #function\n""kernel_thread_helper:\n""	mov	r0, r1\n""	mov	lr, r3\n""	mov	pc, r2\n""	.size	kernel_thread_helper, . - kernel_thread_helper\n""	.previous"); /* * Create a kernel thread. */pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags){	struct pt_regs regs; 	memset(&regs, 0, sizeof(regs)); 	regs.ARM_r1 = (unsigned long)arg;	regs.ARM_r2 = (unsigned long)fn;	regs.ARM_r3 = (unsigned long)do_exit;	regs.ARM_pc = (unsigned long)kernel_thread_helper;	regs.ARM_cpsr = SVC_MODE; 	return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);}EXPORT_SYMBOL(kernel_thread); unsigned long get_wchan(struct task_struct *p){	unsigned long fp, lr;	unsigned long stack_start, stack_end;	int count = 0;	if (!p || p == current || p->state == TASK_RUNNING)		return 0; 	stack_start = (unsigned long)end_of_stack(p);	stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE; 	fp = thread_saved_fp(p);	do {		if (fp < stack_start || fp > stack_end)			return 0;		lr = pc_pointer (((unsigned long *)fp)[-1]);		if (!in_sched_functions(lr))			return lr;		fp = *(unsigned long *) (fp - 12);	} while (count ++ < 16);	return 0;}