[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/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;

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);

extern void call_with_stack(void (*fn)(void *), void *arg, void *sp);
typedef void (*phys_reset_t)(unsigned long);

/*
 * A temporary stack to use for CPU reset. This is static so that we
 * don't clobber it with the identity mapping. When running with this
 * stack, any references to the current task *will not work* so you
 * should really do as little as possible before jumping to your reset
 * code.
 */
static u64 soft_restart_stack[16];

static void __soft_restart(void *addr)
{
	phys_reset_t phys_reset;

	/* Take out a flat memory mapping. */
	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();

	/* Switch to the identity mapping. */
	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
	phys_reset((unsigned long)addr);

	/* Should never get here. */
	BUG();
}

void soft_restart(unsigned long addr)
{
	u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);

	/* Disable interrupts first */
	local_irq_disable();
	local_fiq_disable();

	/* Disable the L2 if we're the last man standing. */
	if (num_online_cpus() == 1)
		outer_disable();

	/* Change to the new stack and continue with the reset. */
	call_with_stack(__soft_restart, (void *)addr, (void *)stack);

	/* Should never get here. */
	BUG();
}

static void null_restart(char mode, const char *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) = null_restart;
EXPORT_SYMBOL_GPL(arm_pm_restart);

/*
 * This is our default idle handler.
 */

void (*arm_pm_idle)(void);

static void default_idle(void)
{
	if (arm_pm_idle)
		arm_pm_idle();
	else
		cpu_do_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_idle_enter();
		rcu_idle_enter();
		leds_event(led_idle_start);
		while (!need_resched()) {
#ifdef CONFIG_HOTPLUG_CPU
			if (cpu_is_offline(smp_processor_id()))
				cpu_die();
#endif

			/*
			 * We need to disable interrupts here
			 * to ensure we don't miss a wakeup call.
			 */
			local_irq_disable();
#ifdef CONFIG_PL310_ERRATA_769419
			wmb();
#endif
			if (hlt_counter) {
				local_irq_enable();
				cpu_relax();
			} else if (!need_resched()) {
				stop_critical_timings();
				if (cpuidle_idle_call())
					pm_idle();
				start_critical_timings();
				/*
				 * pm_idle functions must always
				 * return with IRQs enabled.
				 */
				WARN_ON(irqs_disabled());
			} else
				local_irq_enable();
		}
		leds_event(led_idle_end);
		rcu_idle_exit();
		tick_nohz_idle_exit();
		schedule_preempt_disabled();
	}
}

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();
	local_irq_disable();
	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");
	local_irq_disable();
	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. Insert it into the
 * gate_vma so that it is visible through ptrace and /proc/<pid>/mem.
 */
static struct vm_area_struct gate_vma;

static int __init gate_vma_init(void)
{
	gate_vma.vm_start	= 0xffff0000;
	gate_vma.vm_end		= 0xffff0000 + PAGE_SIZE;
	gate_vma.vm_page_prot	= PAGE_READONLY_EXEC;
	gate_vma.vm_flags	= VM_READ | VM_EXEC |
				  VM_MAYREAD | VM_MAYEXEC;
	return 0;
}
arch_initcall(gate_vma_init);

struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
{
	return &gate_vma;
}

int in_gate_area(struct mm_struct *mm, unsigned long addr)
{
	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
}

int in_gate_area_no_mm(unsigned long addr)
{
	return in_gate_area(NULL, addr);
}

const char *arch_vma_name(struct vm_area_struct *vma)
{
	return (vma == &gate_vma) ? "[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>
d6551e88	38	#include <asm/thread_notify.h>
2d7c11bf	39	#include <asm/stacktrace.h>
2ea83398	40	#include <asm/mach/time.h>
1da177e4	41
c743f380 NP	42	#ifdef CONFIG_CC_STACKPROTECTOR
	43	#include <linux/stackprotector.h>
	44	unsigned long __stack_chk_guard __read_mostly;
	45	EXPORT_SYMBOL(__stack_chk_guard);
	46	#endif
	47
ae0a846e RK	48	static const char *processor_modes[] = {
	49	"USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
	50	"UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
	51	"USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
	52	"UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
	53	};
	54
909d6c6c GD	55	static const char *isa_modes[] = {
	56	"ARM" , "Thumb" , "Jazelle", "ThumbEE"
	57	};
	58
5aafec15	59	extern void setup_mm_for_reboot(void);
1da177e4 LT	60
	61	static volatile int hlt_counter;
	62
1da177e4 LT	63	void disable_hlt(void)
	64	{
	65	hlt_counter++;
	66	}
	67
	68	EXPORT_SYMBOL(disable_hlt);
	69
	70	void enable_hlt(void)
	71	{
	72	hlt_counter--;
	73	}
	74
	75	EXPORT_SYMBOL(enable_hlt);
	76
	77	static int __init nohlt_setup(char *__unused)
	78	{
	79	hlt_counter = 1;
	80	return 1;
	81	}
	82
	83	static int __init hlt_setup(char *__unused)
	84	{
	85	hlt_counter = 0;
	86	return 1;
	87	}
	88
	89	__setup("nohlt", nohlt_setup);
	90	__setup("hlt", hlt_setup);
	91
290130a1 WD	92	extern void call_with_stack(void (fn)(void ), void arg, void sp);
	93	typedef void (*phys_reset_t)(unsigned long);
	94
	95	/*
	96	* A temporary stack to use for CPU reset. This is static so that we
	97	* don't clobber it with the identity mapping. When running with this
	98	* stack, any references to the current task will not work so you
	99	* should really do as little as possible before jumping to your reset
	100	* code.
	101	*/
	102	static u64 soft_restart_stack[16];
	103
	104	static void __soft_restart(void *addr)
74617fb6	105	{
290130a1	106	phys_reset_t phys_reset;
74617fb6	107
290130a1	108	/* Take out a flat memory mapping. */
5aafec15	109	setup_mm_for_reboot();
74617fb6	110
9ca03a21 RK	111	/* Clean and invalidate caches */
	112	flush_cache_all();
	113
	114	/* Turn off caching */
	115	cpu_proc_fin();
	116
	117	/* Push out any further dirty data, and ensure cache is empty */
	118	flush_cache_all();
	119
290130a1 WD	120	/* Switch to the identity mapping. */
	121	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
	122	phys_reset((unsigned long)addr);
74617fb6	123
290130a1 WD	124	/* Should never get here. */
	125	BUG();
	126	}
	127
	128	void soft_restart(unsigned long addr)
	129	{
	130	u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack);
	131
	132	/* Disable interrupts first */
	133	local_irq_disable();
	134	local_fiq_disable();
	135
	136	/* Disable the L2 if we're the last man standing. */
	137	if (num_online_cpus() == 1)
	138	outer_disable();
	139
	140	/* Change to the new stack and continue with the reset. */
	141	call_with_stack(__soft_restart, (void )addr, (void )stack);
	142
	143	/* Should never get here. */
	144	BUG();
e879c862 RK	145	}
e879c862 RK	146
f88b8979	147	static void null_restart(char mode, const char *cmd)
e879c862	148	{
74617fb6 RP	149	}
74617fb6 RP	150
1da177e4	151	/*
74617fb6	152	* Function pointers to optional machine specific functions
1da177e4	153	*/
1da177e4 LT	154	void (*pm_power_off)(void);
	155	EXPORT_SYMBOL(pm_power_off);
	156
f88b8979	157	void (arm_pm_restart)(char str, const char cmd) = null_restart;
74617fb6 RP	158	EXPORT_SYMBOL_GPL(arm_pm_restart);
74617fb6 RP	159
1da177e4	160	/*
4fa20439	161	* This is our default idle handler.
1da177e4	162	*/
4fa20439 NP	163
	164	void (*arm_pm_idle)(void);
	165
84dff1a7	166	static void default_idle(void)
1da177e4	167	{
4fa20439 NP	168	if (arm_pm_idle)
	169	arm_pm_idle();
	170	else
ae940913	171	cpu_do_idle();
9ccdac36	172	local_irq_enable();
1da177e4 LT	173	}
1da177e4 LT	174
9ccdac36 RK	175	void (*pm_idle)(void) = default_idle;
	176	EXPORT_SYMBOL(pm_idle);
	177
1da177e4	178	/*
9ccdac36 RK	179	* The idle thread, has rather strange semantics for calling pm_idle,
	180	* but this is what x86 does and we need to do the same, so that
	181	* things like cpuidle get called in the same way. The only difference
	182	* is that we always respect 'hlt_counter' to prevent low power idle.
1da177e4 LT	183	*/
	184	void cpu_idle(void)
	185	{
	186	local_fiq_enable();
	187
	188	/* endless idle loop with no priority at all */
	189	while (1) {
1268fbc7 FW	190	tick_nohz_idle_enter();
1268fbc7 FW	191	rcu_idle_enter();
9ccdac36 RK	192	leds_event(led_idle_start);
9ccdac36 RK	193	while (!need_resched()) {
a054a811	194	#ifdef CONFIG_HOTPLUG_CPU
9ccdac36 RK	195	if (cpu_is_offline(smp_processor_id()))
9ccdac36 RK	196	cpu_die();
a054a811 RK	197	#endif
a054a811 RK	198
4fa20439 NP	199	/*
	200	* We need to disable interrupts here
	201	* to ensure we don't miss a wakeup call.
	202	*/
9ccdac36	203	local_irq_disable();
11ed0ba1 WD	204	#ifdef CONFIG_PL310_ERRATA_769419
	205	wmb();
	206	#endif
9ccdac36 RK	207	if (hlt_counter) {
	208	local_irq_enable();
	209	cpu_relax();
4fa20439	210	} else if (!need_resched()) {
9ccdac36	211	stop_critical_timings();
cbc158d6	212	if (cpuidle_idle_call())
a0bfa137	213	pm_idle();
9ccdac36 RK	214	start_critical_timings();
9ccdac36 RK	215	/*
4fa20439 NP	216	* pm_idle functions must always
4fa20439 NP	217	* return with IRQs enabled.
9ccdac36 RK	218	*/
9ccdac36 RK	219	WARN_ON(irqs_disabled());
4fa20439	220	} else
9ccdac36	221	local_irq_enable();
9ccdac36	222	}
1da177e4	223	leds_event(led_idle_end);
1268fbc7 FW	224	rcu_idle_exit();
1268fbc7 FW	225	tick_nohz_idle_exit();
bd2f5536	226	schedule_preempt_disabled();
1da177e4 LT	227	}
	228	}
	229
	230	static char reboot_mode = 'h';
	231
	232	int __init reboot_setup(char *str)
	233	{
	234	reboot_mode = str[0];
	235	return 1;
	236	}
	237
	238	__setup("reboot=", reboot_setup);
	239
3d3f78d7	240	void machine_shutdown(void)
1da177e4	241	{
3d3f78d7 RK	242	#ifdef CONFIG_SMP
	243	smp_send_stop();
	244	#endif
1da177e4 LT	245	}
1da177e4 LT	246
3d3f78d7 RK	247	void machine_halt(void)
	248	{
	249	machine_shutdown();
98bd8b96	250	local_irq_disable();
3d3f78d7 RK	251	while (1);
3d3f78d7 RK	252	}
1da177e4 LT	253
	254	void machine_power_off(void)
	255	{
3d3f78d7	256	machine_shutdown();
1da177e4 LT	257	if (pm_power_off)
	258	pm_power_off();
	259	}
	260
be093beb	261	void machine_restart(char *cmd)
1da177e4	262	{
3d3f78d7	263	machine_shutdown();
ac15e00b	264
be093beb	265	arm_pm_restart(reboot_mode, cmd);
ac15e00b RK	266
	267	/* Give a grace period for failure to restart of 1s */
	268	mdelay(1000);
	269
	270	/* Whoops - the platform was unable to reboot. Tell the user! */
	271	printk("Reboot failed -- System halted\n");
98bd8b96	272	local_irq_disable();
ac15e00b	273	while (1);
1da177e4 LT	274	}
1da177e4 LT	275
652a12ef	276	void __show_regs(struct pt_regs *regs)
1da177e4	277	{
154c772e RK	278	unsigned long flags;
154c772e RK	279	char buf[64];
1da177e4	280
154c772e	281	printk("CPU: %d %s (%s %.*s)\n",
22325525 RV	282	raw_smp_processor_id(), print_tainted(),
22325525 RV	283	init_utsname()->release,
154c772e RK	284	(int)strcspn(init_utsname()->version, " "),
154c772e RK	285	init_utsname()->version);
1da177e4 LT	286	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	287	print_symbol("LR is at %s\n", regs->ARM_lr);
154c772e	288	printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
1da177e4	289	"sp : %08lx ip : %08lx fp : %08lx\n",
154c772e RK	290	regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
154c772e RK	291	regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
1da177e4 LT	292	printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
	293	regs->ARM_r10, regs->ARM_r9,
	294	regs->ARM_r8);
	295	printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	296	regs->ARM_r7, regs->ARM_r6,
	297	regs->ARM_r5, regs->ARM_r4);
	298	printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	299	regs->ARM_r3, regs->ARM_r2,
	300	regs->ARM_r1, regs->ARM_r0);
154c772e RK	301
	302	flags = regs->ARM_cpsr;
	303	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
	304	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	305	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	306	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	307	buf[4] = '\0';
	308
909d6c6c	309	printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
154c772e	310	buf, interrupts_enabled(regs) ? "n" : "ff",
1da177e4 LT	311	fast_interrupts_enabled(regs) ? "n" : "ff",
1da177e4 LT	312	processor_modes[processor_mode(regs)],
909d6c6c	313	isa_modes[isa_mode(regs)],
1da177e4	314	get_fs() == get_ds() ? "kernel" : "user");
154c772e	315	#ifdef CONFIG_CPU_CP15
1da177e4	316	{
f12d0d7c	317	unsigned int ctrl;
154c772e RK	318
154c772e RK	319	buf[0] = '\0';
f12d0d7c	320	#ifdef CONFIG_CPU_CP15_MMU
154c772e RK	321	{
	322	unsigned int transbase, dac;
	323	asm("mrc p15, 0, %0, c2, c0\n\t"
	324	"mrc p15, 0, %1, c3, c0\n"
	325	: "=r" (transbase), "=r" (dac));
	326	snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
	327	transbase, dac);
	328	}
f12d0d7c	329	#endif
154c772e RK	330	asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
	331
	332	printk("Control: %08x%s\n", ctrl, buf);
	333	}
f12d0d7c	334	#endif
1da177e4 LT	335	}
1da177e4 LT	336
652a12ef RK	337	void show_regs(struct pt_regs * regs)
	338	{
	339	printk("\n");
19c5870c	340	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
652a12ef	341	__show_regs(regs);
b380ab4f	342	dump_stack();
652a12ef RK	343	}
652a12ef RK	344
797245f5 RK	345	ATOMIC_NOTIFIER_HEAD(thread_notify_head);
	346
	347	EXPORT_SYMBOL_GPL(thread_notify_head);
	348
1da177e4 LT	349	/*
	350	* Free current thread data structures etc..
	351	*/
	352	void exit_thread(void)
	353	{
797245f5	354	thread_notify(THREAD_NOTIFY_EXIT, current_thread_info());
1da177e4 LT	355	}
1da177e4 LT	356
1da177e4 LT	357	void flush_thread(void)
	358	{
	359	struct thread_info *thread = current_thread_info();
	360	struct task_struct *tsk = current;
	361
864232fa WD	362	flush_ptrace_hw_breakpoint(tsk);
864232fa WD	363
1da177e4 LT	364	memset(thread->used_cp, 0, sizeof(thread->used_cp));
1da177e4 LT	365	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
d6551e88 RK	366	memset(&thread->fpstate, 0, sizeof(union fp_state));
	367
	368	thread_notify(THREAD_NOTIFY_FLUSH, thread);
1da177e4 LT	369	}
	370
	371	void release_thread(struct task_struct *dead_task)
	372	{
1da177e4 LT	373	}
	374
	375	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
	376
	377	int
6f2c55b8	378	copy_thread(unsigned long clone_flags, unsigned long stack_start,
1da177e4 LT	379	unsigned long stk_sz, struct task_struct p, struct pt_regs regs)
1da177e4 LT	380	{
815d5ec8 AV	381	struct thread_info *thread = task_thread_info(p);
815d5ec8 AV	382	struct pt_regs *childregs = task_pt_regs(p);
1da177e4	383
1da177e4 LT	384	childregs = regs;
	385	childregs->ARM_r0 = 0;
	386	childregs->ARM_sp = stack_start;
	387
	388	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
	389	thread->cpu_context.sp = (unsigned long)childregs;
	390	thread->cpu_context.pc = (unsigned long)ret_from_fork;
	391
864232fa WD	392	clear_ptrace_hw_breakpoint(p);
864232fa WD	393
1da177e4 LT	394	if (clone_flags & CLONE_SETTLS)
	395	thread->tp_value = regs->ARM_r3;
	396
2e82669a CM	397	thread_notify(THREAD_NOTIFY_COPY, thread);
2e82669a CM	398
1da177e4 LT	399	return 0;
	400	}
	401
cde3f860 AB	402	/*
	403	* Fill in the task's elfregs structure for a core dump.
	404	*/
	405	int dump_task_regs(struct task_struct t, elf_gregset_t elfregs)
	406	{
	407	elf_core_copy_regs(elfregs, task_pt_regs(t));
	408	return 1;
	409	}
	410
1da177e4 LT	411	/*
	412	* fill in the fpe structure for a core dump...
	413	*/
	414	int dump_fpu (struct pt_regs regs, struct user_fp fp)
	415	{
	416	struct thread_info *thread = current_thread_info();
	417	int used_math = thread->used_cp[1] \| thread->used_cp[2];
	418
	419	if (used_math)
	420	memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
	421
	422	return used_math != 0;
	423	}
	424	EXPORT_SYMBOL(dump_fpu);
	425
1da177e4 LT	426	/*
1da177e4 LT	427	* Shuffle the argument into the correct register before calling the
ac78884e RK	428	* thread function. r4 is the thread argument, r5 is the pointer to
ac78884e RK	429	* the thread function, and r6 points to the exit function.
1da177e4 LT	430	*/
1da177e4 LT	431	extern void kernel_thread_helper(void);
4260415f	432	asm( ".pushsection .text\n"
1da177e4 LT	433	" .align\n"
	434	" .type kernel_thread_helper, #function\n"
	435	"kernel_thread_helper:\n"
ac78884e RK	436	#ifdef CONFIG_TRACE_IRQFLAGS
	437	" bl trace_hardirqs_on\n"
	438	#endif
	439	" msr cpsr_c, r7\n"
	440	" mov r0, r4\n"
	441	" mov lr, r6\n"
	442	" mov pc, r5\n"
1da177e4	443	" .size kernel_thread_helper, . - kernel_thread_helper\n"
4260415f	444	" .popsection");
1da177e4	445
feb97c36 CM	446	#ifdef CONFIG_ARM_UNWIND
feb97c36 CM	447	extern void kernel_thread_exit(long code);
4260415f	448	asm( ".pushsection .text\n"
feb97c36 CM	449	" .align\n"
	450	" .type kernel_thread_exit, #function\n"
	451	"kernel_thread_exit:\n"
	452	" .fnstart\n"
	453	" .cantunwind\n"
	454	" bl do_exit\n"
	455	" nop\n"
	456	" .fnend\n"
	457	" .size kernel_thread_exit, . - kernel_thread_exit\n"
4260415f	458	" .popsection");
feb97c36 CM	459	#else
	460	#define kernel_thread_exit do_exit
	461	#endif
	462
1da177e4 LT	463	/*
	464	* Create a kernel thread.
	465	*/
	466	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
	467	{
	468	struct pt_regs regs;
	469
	470	memset(&regs, 0, sizeof(regs));
	471
ac78884e RK	472	regs.ARM_r4 = (unsigned long)arg;
	473	regs.ARM_r5 = (unsigned long)fn;
	474	regs.ARM_r6 = (unsigned long)kernel_thread_exit;
	475	regs.ARM_r7 = SVC_MODE \| PSR_ENDSTATE \| PSR_ISETSTATE;
1da177e4	476	regs.ARM_pc = (unsigned long)kernel_thread_helper;
ac78884e	477	regs.ARM_cpsr = regs.ARM_r7 \| PSR_I_BIT;
1da177e4 LT	478
	479	return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
	480	}
	481	EXPORT_SYMBOL(kernel_thread);
	482
	483	unsigned long get_wchan(struct task_struct *p)
	484	{
2d7c11bf	485	struct stackframe frame;
1da177e4 LT	486	int count = 0;
	487	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	488	return 0;
	489
2d7c11bf CM	490	frame.fp = thread_saved_fp(p);
	491	frame.sp = thread_saved_sp(p);
	492	frame.lr = 0; /* recovered from the stack */
	493	frame.pc = thread_saved_pc(p);
1da177e4	494	do {
2d7c11bf CM	495	int ret = unwind_frame(&frame);
2d7c11bf CM	496	if (ret < 0)
1da177e4	497	return 0;
2d7c11bf CM	498	if (!in_sched_functions(frame.pc))
2d7c11bf CM	499	return frame.pc;
1da177e4 LT	500	} while (count ++ < 16);
	501	return 0;
	502	}
990cb8ac NP	503
	504	unsigned long arch_randomize_brk(struct mm_struct *mm)
	505	{
	506	unsigned long range_end = mm->brk + 0x02000000;
	507	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
	508	}
ec706dab	509
6cde6d42	510	#ifdef CONFIG_MMU
ec706dab NP	511	/*
ec706dab NP	512	* The vectors page is always readable from user space for the
f9d4861f WD	513	* atomic helpers and the signal restart code. Insert it into the
f9d4861f WD	514	* gate_vma so that it is visible through ptrace and /proc/<pid>/mem.
ec706dab	515	*/
f9d4861f	516	static struct vm_area_struct gate_vma;
ec706dab	517
f9d4861f	518	static int __init gate_vma_init(void)
ec706dab	519	{
f9d4861f WD	520	gate_vma.vm_start = 0xffff0000;
	521	gate_vma.vm_end = 0xffff0000 + PAGE_SIZE;
	522	gate_vma.vm_page_prot = PAGE_READONLY_EXEC;
	523	gate_vma.vm_flags = VM_READ \| VM_EXEC \|
12679a2d	524	VM_MAYREAD \| VM_MAYEXEC;
f9d4861f WD	525	return 0;
	526	}
	527	arch_initcall(gate_vma_init);
	528
	529	struct vm_area_struct get_gate_vma(struct mm_struct mm)
	530	{
	531	return &gate_vma;
	532	}
	533
	534	int in_gate_area(struct mm_struct *mm, unsigned long addr)
	535	{
	536	return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end);
	537	}
	538
	539	int in_gate_area_no_mm(unsigned long addr)
	540	{
	541	return in_gate_area(NULL, addr);
ec706dab NP	542	}
	543
	544	const char arch_vma_name(struct vm_area_struct vma)
	545	{
f9d4861f	546	return (vma == &gate_vma) ? "[vectors]" : NULL;
ec706dab	547	}
6cde6d42	548	#endif