[deliverable/linux.git] / arch / arm / kernel / process.c

/*
 *  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/export.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/user.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 <linux/tick.h>
#include <linux/utsname.h>
#include <linux/uaccess.h>
#include <linux/random.h>
#include <linux/hw_breakpoint.h>
#include <linux/cpuidle.h>

#include <asm/cacheflush.h>
#include <asm/leds.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/thread_notify.h>
#include <asm/stacktrace.h>
#include <asm/mach/time.h>

#ifdef CONFIG_CC_STACKPROTECTOR
#include <linux/stackprotector.h>
unsigned long __stack_chk_guard __read_mostly;
EXPORT_SYMBOL(__stack_chk_guard);
#endif

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"
};

static const char *isa_modes[] = {
  "ARM" , "Thumb" , "Jazelle", "ThumbEE"
};

extern void setup_mm_for_reboot(void);

static volatile int hlt_counter;

#include <mach/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 soft_restart(unsigned long addr)
{
	/* Disable interrupts first */
	local_irq_disable();
	local_fiq_disable();

	/*
	 * 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();

	/* Clean and invalidate caches */
	flush_cache_all();

	/* Turn off caching */
	cpu_proc_fin();

	/* Push out any further dirty data, and ensure cache is empty */
	flush_cache_all();

	cpu_reset(addr);
}

void arm_machine_restart(char mode, const char *cmd)
{
	/* Disable interrupts first */
	local_irq_disable();
	local_fiq_disable();

	/* Call the architecture specific reboot code. */
	arch_reset(mode, cmd);
}

/*
 * Function pointers to optional machine specific functions
 */
void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);

void (*arm_pm_restart)(char str, const char *cmd) = arm_machine_restart;
EXPORT_SYMBOL_GPL(arm_pm_restart);

static void do_nothing(void *unused)
{
}

/*
 * cpu_idle_wait - Used to ensure that all the CPUs discard old value of
 * pm_idle and update to new pm_idle value. Required while changing pm_idle
 * handler on SMP systems.
 *
 * Caller must have changed pm_idle to the new value before the call. Old
 * pm_idle value will not be used by any CPU after the return of this function.
 */
void cpu_idle_wait(void)
{
	smp_mb();
	/* kick all the CPUs so that they exit out of pm_idle */
	smp_call_function(do_nothing, NULL, 1);
}
EXPORT_SYMBOL_GPL(cpu_idle_wait);

/*
 * 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 (!need_resched())
		arch_idle();
	local_irq_enable();
}

void (*pm_idle)(void) = default_idle;
EXPORT_SYMBOL(pm_idle);

/*
 * The idle thread, has rather strange semantics for calling pm_idle,
 * but this is what x86 does and we need to do the same, so that
 * things like cpuidle get called in the same way.  The only difference
 * is that we always respect 'hlt_counter' to prevent low power idle.
 */
void cpu_idle(void)
{
	local_fiq_enable();

	/* endless idle loop with no priority at all */
	while (1) {
		tick_nohz_stop_sched_tick(1);
		leds_event(led_idle_start);
		while (!need_resched()) {
#ifdef CONFIG_HOTPLUG_CPU
			if (cpu_is_offline(smp_processor_id()))
				cpu_die();
#endif

			local_irq_disable();
#ifdef CONFIG_PL310_ERRATA_769419
			wmb();
#endif
			if (hlt_counter) {
				local_irq_enable();
				cpu_relax();
			} else {
				stop_critical_timings();
				if (cpuidle_idle_call())
					pm_idle();
				start_critical_timings();
				/*
				 * This will eventually be removed - pm_idle
				 * functions should always return with IRQs
				 * enabled.
				 */
				WARN_ON(irqs_disabled());
				local_irq_enable();
			}
		}
		leds_event(led_idle_end);
		tick_nohz_restart_sched_tick();
		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_shutdown(void)
{
#ifdef CONFIG_SMP
	smp_send_stop();
#endif
}

void machine_halt(void)
{
	machine_shutdown();
	while (1);
}

void machine_power_off(void)
{
	machine_shutdown();
	if (pm_power_off)
		pm_power_off();
}

void machine_restart(char *cmd)
{
	machine_shutdown();

	arm_pm_restart(reboot_mode, cmd);

	/* Give a grace period for failure to restart of 1s */
	mdelay(1000);

	/* Whoops - the platform was unable to reboot. Tell the user! */
	printk("Reboot failed -- System halted\n");
	while (1);
}

void __show_regs(struct pt_regs *regs)
{
	unsigned long flags;
	char buf[64];

	printk("CPU: %d    %s  (%s %.*s)\n",
		raw_smp_processor_id(), print_tainted(),
		init_utsname()->release,
		(int)strcspn(init_utsname()->version, " "),
		init_utsname()->version);
	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>]    psr: %08lx\n"
	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
		regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
		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);

	flags = regs->ARM_cpsr;
	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	buf[4] = '\0';

	printk("Flags: %s  IRQs o%s  FIQs o%s  Mode %s  ISA %s  Segment %s\n",
		buf, interrupts_enabled(regs) ? "n" : "ff",
		fast_interrupts_enabled(regs) ? "n" : "ff",
		processor_modes[processor_mode(regs)],
		isa_modes[isa_mode(regs)],
		get_fs() == get_ds() ? "kernel" : "user");
#ifdef CONFIG_CPU_CP15
	{
		unsigned int ctrl;

		buf[0] = '\0';
#ifdef CONFIG_CPU_CP15_MMU
		{
			unsigned int transbase, dac;
			asm("mrc p15, 0, %0, c2, c0\n\t"
			    "mrc p15, 0, %1, c3, c0\n"
			    : "=r" (transbase), "=r" (dac));
			snprintf(buf, sizeof(buf), "  Table: %08x  DAC: %08x",
			  	transbase, dac);
		}
#endif
		asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));

		printk("Control: %08x%s\n", ctrl, buf);
	}
#endif
}

void show_regs(struct pt_regs * regs)
{
	printk("\n");
	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
	__show_regs(regs);
	dump_stack();
}

ATOMIC_NOTIFIER_HEAD(thread_notify_head);

EXPORT_SYMBOL_GPL(thread_notify_head);

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
}

void flush_thread(void)
{
	struct thread_info *thread = current_thread_info();
	struct task_struct *tsk = current;

	flush_ptrace_hw_breakpoint(tsk);

	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)
{
}

asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");

int
copy_thread(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;

	clear_ptrace_hw_breakpoint(p);

	if (clone_flags & CLONE_SETTLS)
		thread->tp_value = regs->ARM_r3;

	thread_notify(THREAD_NOTIFY_COPY, thread);

	return 0;
}

/*
 * Fill in the task's elfregs structure for a core dump.
 */
int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs)
{
	elf_core_copy_regs(elfregs, task_pt_regs(t));
	return 1;
}

/*
 * 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);

/*
 * Shuffle the argument into the correct register before calling the
 * thread function.  r4 is the thread argument, r5 is the pointer to
 * the thread function, and r6 points to the exit function.
 */
extern void kernel_thread_helper(void);
asm(	".pushsection .text\n"
"	.align\n"
"	.type	kernel_thread_helper, #function\n"
"kernel_thread_helper:\n"
#ifdef CONFIG_TRACE_IRQFLAGS
"	bl	trace_hardirqs_on\n"
#endif
"	msr	cpsr_c, r7\n"
"	mov	r0, r4\n"
"	mov	lr, r6\n"
"	mov	pc, r5\n"
"	.size	kernel_thread_helper, . - kernel_thread_helper\n"
"	.popsection");

#ifdef CONFIG_ARM_UNWIND
extern void kernel_thread_exit(long code);
asm(	".pushsection .text\n"
"	.align\n"
"	.type	kernel_thread_exit, #function\n"
"kernel_thread_exit:\n"
"	.fnstart\n"
"	.cantunwind\n"
"	bl	do_exit\n"
"	nop\n"
"	.fnend\n"
"	.size	kernel_thread_exit, . - kernel_thread_exit\n"
"	.popsection");
#else
#define kernel_thread_exit	do_exit
#endif

/*
 * 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_r4 = (unsigned long)arg;
	regs.ARM_r5 = (unsigned long)fn;
	regs.ARM_r6 = (unsigned long)kernel_thread_exit;
	regs.ARM_r7 = SVC_MODE | PSR_ENDSTATE | PSR_ISETSTATE;
	regs.ARM_pc = (unsigned long)kernel_thread_helper;
	regs.ARM_cpsr = regs.ARM_r7 | PSR_I_BIT;

	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)
{
	struct stackframe frame;
	int count = 0;
	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	frame.fp = thread_saved_fp(p);
	frame.sp = thread_saved_sp(p);
	frame.lr = 0;			/* recovered from the stack */
	frame.pc = thread_saved_pc(p);
	do {
		int ret = unwind_frame(&frame);
		if (ret < 0)
			return 0;
		if (!in_sched_functions(frame.pc))
			return frame.pc;
	} while (count ++ < 16);
	return 0;
}

unsigned long arch_randomize_brk(struct mm_struct *mm)
{
	unsigned long range_end = mm->brk + 0x02000000;
	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
}

#ifdef CONFIG_MMU
/*
 * The vectors page is always readable from user space for the
 * atomic helpers and the signal restart code.  Let's declare a mapping
 * for it so it is visible through ptrace and /proc/<pid>/mem.
 */

int vectors_user_mapping(void)
{
	struct mm_struct *mm = current->mm;
	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
				       VM_READ | VM_EXEC |
				       VM_MAYREAD | VM_MAYEXEC |
				       VM_ALWAYSDUMP | VM_RESERVED,
				       NULL);
}

const char *arch_vma_name(struct vm_area_struct *vma)
{
	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/arch/arm/kernel/process.c
	3	*
	4	* Copyright (C) 1996-2000 Russell King - Converted to ARM.
	5	* Original Copyright (C) 1995 Linus Torvalds
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11	#include <stdarg.h>
	12
ecea4ab6	13	#include <linux/export.h>
1da177e4 LT	14	#include <linux/sched.h>
	15	#include <linux/kernel.h>
	16	#include <linux/mm.h>
	17	#include <linux/stddef.h>
	18	#include <linux/unistd.h>
1da177e4	19	#include <linux/user.h>
1da177e4 LT	20	#include <linux/delay.h>
	21	#include <linux/reboot.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/kallsyms.h>
	24	#include <linux/init.h>
a054a811	25	#include <linux/cpu.h>
84dff1a7	26	#include <linux/elfcore.h>
74617fb6	27	#include <linux/pm.h>
9e4559dd	28	#include <linux/tick.h>
154c772e	29	#include <linux/utsname.h>
33fa9b13	30	#include <linux/uaccess.h>
990cb8ac	31	#include <linux/random.h>
864232fa	32	#include <linux/hw_breakpoint.h>
a0bfa137	33	#include <linux/cpuidle.h>
1da177e4	34
9ca03a21	35	#include <asm/cacheflush.h>
1da177e4 LT	36	#include <asm/leds.h>
1da177e4 LT	37	#include <asm/processor.h>
78ff18a4	38	#include <asm/system.h>
d6551e88	39	#include <asm/thread_notify.h>
2d7c11bf	40	#include <asm/stacktrace.h>
2ea83398	41	#include <asm/mach/time.h>
1da177e4	42
c743f380 NP	43	#ifdef CONFIG_CC_STACKPROTECTOR
	44	#include <linux/stackprotector.h>
	45	unsigned long __stack_chk_guard __read_mostly;
	46	EXPORT_SYMBOL(__stack_chk_guard);
	47	#endif
	48
ae0a846e RK	49	static const char *processor_modes[] = {
	50	"USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
	51	"UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
	52	"USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
	53	"UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
	54	};
	55
909d6c6c GD	56	static const char *isa_modes[] = {
	57	"ARM" , "Thumb" , "Jazelle", "ThumbEE"
	58	};
	59
5aafec15	60	extern void setup_mm_for_reboot(void);
1da177e4 LT	61
	62	static volatile int hlt_counter;
	63
a09e64fb	64	#include <mach/system.h>
1da177e4 LT	65
	66	void disable_hlt(void)
	67	{
	68	hlt_counter++;
	69	}
	70
	71	EXPORT_SYMBOL(disable_hlt);
	72
	73	void enable_hlt(void)
	74	{
	75	hlt_counter--;
	76	}
	77
	78	EXPORT_SYMBOL(enable_hlt);
	79
	80	static int __init nohlt_setup(char *__unused)
	81	{
	82	hlt_counter = 1;
	83	return 1;
	84	}
	85
	86	static int __init hlt_setup(char *__unused)
	87	{
	88	hlt_counter = 0;
	89	return 1;
	90	}
	91
	92	__setup("nohlt", nohlt_setup);
	93	__setup("hlt", hlt_setup);
	94
e879c862	95	void soft_restart(unsigned long addr)
74617fb6	96	{
9ca03a21 RK	97	/* Disable interrupts first */
	98	local_irq_disable();
	99	local_fiq_disable();
74617fb6 RP	100
	101	/*
	102	* Tell the mm system that we are going to reboot -
	103	* we may need it to insert some 1:1 mappings so that
	104	* soft boot works.
	105	*/
5aafec15	106	setup_mm_for_reboot();
74617fb6	107
9ca03a21 RK	108	/* Clean and invalidate caches */
	109	flush_cache_all();
	110
	111	/* Turn off caching */
	112	cpu_proc_fin();
	113
	114	/* Push out any further dirty data, and ensure cache is empty */
	115	flush_cache_all();
	116
e879c862 RK	117	cpu_reset(addr);
	118	}
	119
	120	void arm_machine_restart(char mode, const char *cmd)
	121	{
	122	/* Disable interrupts first */
	123	local_irq_disable();
	124	local_fiq_disable();
	125
	126	/* Call the architecture specific reboot code. */
be093beb	127	arch_reset(mode, cmd);
74617fb6 RP	128	}
74617fb6 RP	129
1da177e4	130	/*
74617fb6	131	* Function pointers to optional machine specific functions
1da177e4	132	*/
1da177e4 LT	133	void (*pm_power_off)(void);
	134	EXPORT_SYMBOL(pm_power_off);
	135
be093beb	136	void (arm_pm_restart)(char str, const char cmd) = arm_machine_restart;
74617fb6 RP	137	EXPORT_SYMBOL_GPL(arm_pm_restart);
74617fb6 RP	138
c7b0aff4 KH	139	static void do_nothing(void *unused)
	140	{
	141	}
	142
	143	/*
	144	* cpu_idle_wait - Used to ensure that all the CPUs discard old value of
	145	* pm_idle and update to new pm_idle value. Required while changing pm_idle
	146	* handler on SMP systems.
	147	*
	148	* Caller must have changed pm_idle to the new value before the call. Old
	149	* pm_idle value will not be used by any CPU after the return of this function.
	150	*/
	151	void cpu_idle_wait(void)
	152	{
	153	smp_mb();
	154	/* kick all the CPUs so that they exit out of pm_idle */
	155	smp_call_function(do_nothing, NULL, 1);
	156	}
	157	EXPORT_SYMBOL_GPL(cpu_idle_wait);
74617fb6	158
1da177e4 LT	159	/*
	160	* This is our default idle handler. We need to disable
	161	* interrupts here to ensure we don't miss a wakeup call.
	162	*/
84dff1a7	163	static void default_idle(void)
1da177e4	164	{
9ccdac36 RK	165	if (!need_resched())
	166	arch_idle();
	167	local_irq_enable();
1da177e4 LT	168	}
1da177e4 LT	169
9ccdac36 RK	170	void (*pm_idle)(void) = default_idle;
	171	EXPORT_SYMBOL(pm_idle);
	172
1da177e4	173	/*
9ccdac36 RK	174	* The idle thread, has rather strange semantics for calling pm_idle,
	175	* but this is what x86 does and we need to do the same, so that
	176	* things like cpuidle get called in the same way. The only difference
	177	* is that we always respect 'hlt_counter' to prevent low power idle.
1da177e4 LT	178	*/
	179	void cpu_idle(void)
	180	{
	181	local_fiq_enable();
	182
	183	/* endless idle loop with no priority at all */
	184	while (1) {
9ccdac36 RK	185	tick_nohz_stop_sched_tick(1);
	186	leds_event(led_idle_start);
	187	while (!need_resched()) {
a054a811	188	#ifdef CONFIG_HOTPLUG_CPU
9ccdac36 RK	189	if (cpu_is_offline(smp_processor_id()))
9ccdac36 RK	190	cpu_die();
a054a811 RK	191	#endif
a054a811 RK	192
9ccdac36	193	local_irq_disable();
11ed0ba1 WD	194	#ifdef CONFIG_PL310_ERRATA_769419
	195	wmb();
	196	#endif
9ccdac36 RK	197	if (hlt_counter) {
	198	local_irq_enable();
	199	cpu_relax();
	200	} else {
	201	stop_critical_timings();
cbc158d6	202	if (cpuidle_idle_call())
a0bfa137	203	pm_idle();
9ccdac36 RK	204	start_critical_timings();
	205	/*
	206	* This will eventually be removed - pm_idle
	207	* functions should always return with IRQs
	208	* enabled.
	209	*/
	210	WARN_ON(irqs_disabled());
	211	local_irq_enable();
	212	}
	213	}
1da177e4	214	leds_event(led_idle_end);
9e4559dd	215	tick_nohz_restart_sched_tick();
5bfb5d69	216	preempt_enable_no_resched();
1da177e4	217	schedule();
5bfb5d69	218	preempt_disable();
1da177e4 LT	219	}
	220	}
	221
	222	static char reboot_mode = 'h';
	223
	224	int __init reboot_setup(char *str)
	225	{
	226	reboot_mode = str[0];
	227	return 1;
	228	}
	229
	230	__setup("reboot=", reboot_setup);
	231
3d3f78d7	232	void machine_shutdown(void)
1da177e4	233	{
3d3f78d7 RK	234	#ifdef CONFIG_SMP
	235	smp_send_stop();
	236	#endif
1da177e4 LT	237	}
1da177e4 LT	238
3d3f78d7 RK	239	void machine_halt(void)
	240	{
	241	machine_shutdown();
	242	while (1);
	243	}
1da177e4 LT	244
	245	void machine_power_off(void)
	246	{
3d3f78d7	247	machine_shutdown();
1da177e4 LT	248	if (pm_power_off)
	249	pm_power_off();
	250	}
	251
be093beb	252	void machine_restart(char *cmd)
1da177e4	253	{
3d3f78d7	254	machine_shutdown();
ac15e00b	255
be093beb	256	arm_pm_restart(reboot_mode, cmd);
ac15e00b RK	257
	258	/* Give a grace period for failure to restart of 1s */
	259	mdelay(1000);
	260
	261	/* Whoops - the platform was unable to reboot. Tell the user! */
	262	printk("Reboot failed -- System halted\n");
	263	while (1);
1da177e4 LT	264	}
1da177e4 LT	265
652a12ef	266	void __show_regs(struct pt_regs *regs)
1da177e4	267	{
154c772e RK	268	unsigned long flags;
154c772e RK	269	char buf[64];
1da177e4	270
154c772e	271	printk("CPU: %d %s (%s %.*s)\n",
22325525 RV	272	raw_smp_processor_id(), print_tainted(),
22325525 RV	273	init_utsname()->release,
154c772e RK	274	(int)strcspn(init_utsname()->version, " "),
154c772e RK	275	init_utsname()->version);
1da177e4 LT	276	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	277	print_symbol("LR is at %s\n", regs->ARM_lr);
154c772e	278	printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
1da177e4	279	"sp : %08lx ip : %08lx fp : %08lx\n",
154c772e RK	280	regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
154c772e RK	281	regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
1da177e4 LT	282	printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
	283	regs->ARM_r10, regs->ARM_r9,
	284	regs->ARM_r8);
	285	printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	286	regs->ARM_r7, regs->ARM_r6,
	287	regs->ARM_r5, regs->ARM_r4);
	288	printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	289	regs->ARM_r3, regs->ARM_r2,
	290	regs->ARM_r1, regs->ARM_r0);
154c772e RK	291
	292	flags = regs->ARM_cpsr;
	293	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
	294	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	295	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	296	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	297	buf[4] = '\0';
	298
909d6c6c	299	printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
154c772e	300	buf, interrupts_enabled(regs) ? "n" : "ff",
1da177e4 LT	301	fast_interrupts_enabled(regs) ? "n" : "ff",
1da177e4 LT	302	processor_modes[processor_mode(regs)],
909d6c6c	303	isa_modes[isa_mode(regs)],
1da177e4	304	get_fs() == get_ds() ? "kernel" : "user");
154c772e	305	#ifdef CONFIG_CPU_CP15
1da177e4	306	{
f12d0d7c	307	unsigned int ctrl;
154c772e RK	308
154c772e RK	309	buf[0] = '\0';
f12d0d7c	310	#ifdef CONFIG_CPU_CP15_MMU
154c772e RK	311	{
	312	unsigned int transbase, dac;
	313	asm("mrc p15, 0, %0, c2, c0\n\t"
	314	"mrc p15, 0, %1, c3, c0\n"
	315	: "=r" (transbase), "=r" (dac));
	316	snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
	317	transbase, dac);
	318	}
f12d0d7c	319	#endif
154c772e RK	320	asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
	321
	322	printk("Control: %08x%s\n", ctrl, buf);
	323	}
f12d0d7c	324	#endif
1da177e4 LT	325	}
1da177e4 LT	326
652a12ef RK	327	void show_regs(struct pt_regs * regs)
	328	{
	329	printk("\n");
19c5870c	330	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
652a12ef	331	__show_regs(regs);
b380ab4f	332	dump_stack();
652a12ef RK	333	}
652a12ef RK	334
797245f5 RK	335	ATOMIC_NOTIFIER_HEAD(thread_notify_head);
	336
	337	EXPORT_SYMBOL_GPL(thread_notify_head);
	338
1da177e4 LT	339	/*
	340	* Free current thread data structures etc..
	341	*/
	342	void exit_thread(void)
	343	{
797245f5	344	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
1da177e4 LT	345	}
1da177e4 LT	346
1da177e4 LT	347	void flush_thread(void)
	348	{
	349	struct thread_info *thread = current_thread_info();
	350	struct task_struct *tsk = current;
	351
864232fa WD	352	flush_ptrace_hw_breakpoint(tsk);
864232fa WD	353
1da177e4 LT	354	memset(thread->used_cp, 0, sizeof(thread->used_cp));
1da177e4 LT	355	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
d6551e88 RK	356	memset(&thread->fpstate, 0, sizeof(union fp_state));
	357
	358	thread_notify(THREAD_NOTIFY_FLUSH, thread);
1da177e4 LT	359	}
	360
	361	void release_thread(struct task_struct *dead_task)
	362	{
1da177e4 LT	363	}
	364
	365	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
	366
	367	int
6f2c55b8	368	copy_thread(unsigned long clone_flags, unsigned long stack_start,
1da177e4 LT	369	unsigned long stk_sz, struct task_struct p, struct pt_regs regs)
1da177e4 LT	370	{
815d5ec8 AV	371	struct thread_info *thread = task_thread_info(p);
815d5ec8 AV	372	struct pt_regs *childregs = task_pt_regs(p);
1da177e4	373
1da177e4 LT	374	childregs = regs;
	375	childregs->ARM_r0 = 0;
	376	childregs->ARM_sp = stack_start;
	377
	378	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
	379	thread->cpu_context.sp = (unsigned long)childregs;
	380	thread->cpu_context.pc = (unsigned long)ret_from_fork;
	381
864232fa WD	382	clear_ptrace_hw_breakpoint(p);
864232fa WD	383
1da177e4 LT	384	if (clone_flags & CLONE_SETTLS)
	385	thread->tp_value = regs->ARM_r3;
	386
2e82669a CM	387	thread_notify(THREAD_NOTIFY_COPY, thread);
2e82669a CM	388
1da177e4 LT	389	return 0;
	390	}
	391
cde3f860 AB	392	/*
	393	* Fill in the task's elfregs structure for a core dump.
	394	*/
	395	int dump_task_regs(struct task_struct t, elf_gregset_t elfregs)
	396	{
	397	elf_core_copy_regs(elfregs, task_pt_regs(t));
	398	return 1;
	399	}
	400
1da177e4 LT	401	/*
	402	* fill in the fpe structure for a core dump...
	403	*/
	404	int dump_fpu (struct pt_regs regs, struct user_fp fp)
	405	{
	406	struct thread_info *thread = current_thread_info();
	407	int used_math = thread->used_cp[1] \| thread->used_cp[2];
	408
	409	if (used_math)
	410	memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
	411
	412	return used_math != 0;
	413	}
	414	EXPORT_SYMBOL(dump_fpu);
	415
1da177e4 LT	416	/*
1da177e4 LT	417	* Shuffle the argument into the correct register before calling the
ac78884e RK	418	* thread function. r4 is the thread argument, r5 is the pointer to
ac78884e RK	419	* the thread function, and r6 points to the exit function.
1da177e4 LT	420	*/
1da177e4 LT	421	extern void kernel_thread_helper(void);
4260415f	422	asm( ".pushsection .text\n"
1da177e4 LT	423	" .align\n"
	424	" .type kernel_thread_helper, #function\n"
	425	"kernel_thread_helper:\n"
ac78884e RK	426	#ifdef CONFIG_TRACE_IRQFLAGS
	427	" bl trace_hardirqs_on\n"
	428	#endif
	429	" msr cpsr_c, r7\n"
	430	" mov r0, r4\n"
	431	" mov lr, r6\n"
	432	" mov pc, r5\n"
1da177e4	433	" .size kernel_thread_helper, . - kernel_thread_helper\n"
4260415f	434	" .popsection");
1da177e4	435
feb97c36 CM	436	#ifdef CONFIG_ARM_UNWIND
feb97c36 CM	437	extern void kernel_thread_exit(long code);
4260415f	438	asm( ".pushsection .text\n"
feb97c36 CM	439	" .align\n"
	440	" .type kernel_thread_exit, #function\n"
	441	"kernel_thread_exit:\n"
	442	" .fnstart\n"
	443	" .cantunwind\n"
	444	" bl do_exit\n"
	445	" nop\n"
	446	" .fnend\n"
	447	" .size kernel_thread_exit, . - kernel_thread_exit\n"
4260415f	448	" .popsection");
feb97c36 CM	449	#else
	450	#define kernel_thread_exit do_exit
	451	#endif
	452
1da177e4 LT	453	/*
	454	* Create a kernel thread.
	455	*/
	456	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
	457	{
	458	struct pt_regs regs;
	459
	460	memset(&regs, 0, sizeof(regs));
	461
ac78884e RK	462	regs.ARM_r4 = (unsigned long)arg;
	463	regs.ARM_r5 = (unsigned long)fn;
	464	regs.ARM_r6 = (unsigned long)kernel_thread_exit;
	465	regs.ARM_r7 = SVC_MODE \| PSR_ENDSTATE \| PSR_ISETSTATE;
1da177e4	466	regs.ARM_pc = (unsigned long)kernel_thread_helper;
ac78884e	467	regs.ARM_cpsr = regs.ARM_r7 \| PSR_I_BIT;
1da177e4 LT	468
	469	return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
	470	}
	471	EXPORT_SYMBOL(kernel_thread);
	472
	473	unsigned long get_wchan(struct task_struct *p)
	474	{
2d7c11bf	475	struct stackframe frame;
1da177e4 LT	476	int count = 0;
	477	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	478	return 0;
	479
2d7c11bf CM	480	frame.fp = thread_saved_fp(p);
	481	frame.sp = thread_saved_sp(p);
	482	frame.lr = 0; /* recovered from the stack */
	483	frame.pc = thread_saved_pc(p);
1da177e4	484	do {
2d7c11bf CM	485	int ret = unwind_frame(&frame);
2d7c11bf CM	486	if (ret < 0)
1da177e4	487	return 0;
2d7c11bf CM	488	if (!in_sched_functions(frame.pc))
2d7c11bf CM	489	return frame.pc;
1da177e4 LT	490	} while (count ++ < 16);
	491	return 0;
	492	}
990cb8ac NP	493
	494	unsigned long arch_randomize_brk(struct mm_struct *mm)
	495	{
	496	unsigned long range_end = mm->brk + 0x02000000;
	497	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
	498	}
ec706dab	499
6cde6d42	500	#ifdef CONFIG_MMU
ec706dab NP	501	/*
	502	* The vectors page is always readable from user space for the
	503	* atomic helpers and the signal restart code. Let's declare a mapping
	504	* for it so it is visible through ptrace and /proc/<pid>/mem.
	505	*/
	506
	507	int vectors_user_mapping(void)
	508	{
	509	struct mm_struct *mm = current->mm;
	510	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
	511	VM_READ \| VM_EXEC \|
	512	VM_MAYREAD \| VM_MAYEXEC \|
	513	VM_ALWAYSDUMP \| VM_RESERVED,
	514	NULL);
	515	}
	516
	517	const char arch_vma_name(struct vm_area_struct vma)
	518	{
	519	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
	520	}
6cde6d42	521	#endif