[mirror_ubuntu-bionic-kernel.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/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/slab.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 <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"
};

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

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);
		tick_nohz_stop_sched_tick();
		while (!need_resched())
			idle();
		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_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;
	char buf[64];

	printk("CPU: %d    %s  (%s %.*s)\n",
		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);
	__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");

int
copy_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);

/*
 * 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;
}
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
1da177e4 LT	13	#include <linux/module.h>
	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 LT	19	#include <linux/slab.h>
1da177e4 LT	20	#include <linux/user.h>
1da177e4 LT	21	#include <linux/delay.h>
	22	#include <linux/reboot.h>
	23	#include <linux/interrupt.h>
	24	#include <linux/kallsyms.h>
	25	#include <linux/init.h>
a054a811	26	#include <linux/cpu.h>
84dff1a7	27	#include <linux/elfcore.h>
74617fb6	28	#include <linux/pm.h>
9e4559dd	29	#include <linux/tick.h>
154c772e	30	#include <linux/utsname.h>
1da177e4	31
1da177e4 LT	32	#include <asm/leds.h>
1da177e4 LT	33	#include <asm/processor.h>
78ff18a4	34	#include <asm/system.h>
d6551e88	35	#include <asm/thread_notify.h>
1da177e4	36	#include <asm/uaccess.h>
2ea83398	37	#include <asm/mach/time.h>
1da177e4	38
ae0a846e RK	39	static const char *processor_modes[] = {
	40	"USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" ,
	41	"UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26",
	42	"USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" ,
	43	"UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32"
	44	};
	45
909d6c6c GD	46	static const char *isa_modes[] = {
	47	"ARM" , "Thumb" , "Jazelle", "ThumbEE"
	48	};
	49
1da177e4 LT	50	extern void setup_mm_for_reboot(char mode);
	51
	52	static volatile int hlt_counter;
	53
	54	#include <asm/arch/system.h>
	55
	56	void disable_hlt(void)
	57	{
	58	hlt_counter++;
	59	}
	60
	61	EXPORT_SYMBOL(disable_hlt);
	62
	63	void enable_hlt(void)
	64	{
	65	hlt_counter--;
	66	}
	67
	68	EXPORT_SYMBOL(enable_hlt);
	69
	70	static int __init nohlt_setup(char *__unused)
	71	{
	72	hlt_counter = 1;
	73	return 1;
	74	}
	75
	76	static int __init hlt_setup(char *__unused)
	77	{
	78	hlt_counter = 0;
	79	return 1;
	80	}
	81
	82	__setup("nohlt", nohlt_setup);
	83	__setup("hlt", hlt_setup);
	84
74617fb6 RP	85	void arm_machine_restart(char mode)
	86	{
	87	/*
	88	* Clean and disable cache, and turn off interrupts
	89	*/
	90	cpu_proc_fin();
	91
	92	/*
	93	* Tell the mm system that we are going to reboot -
	94	* we may need it to insert some 1:1 mappings so that
	95	* soft boot works.
	96	*/
	97	setup_mm_for_reboot(mode);
	98
	99	/*
	100	* Now call the architecture specific reboot code.
	101	*/
	102	arch_reset(mode);
	103
	104	/*
	105	* Whoops - the architecture was unable to reboot.
	106	* Tell the user!
	107	*/
	108	mdelay(1000);
	109	printk("Reboot failed -- System halted\n");
	110	while (1);
	111	}
	112
1da177e4	113	/*
74617fb6	114	* Function pointers to optional machine specific functions
1da177e4 LT	115	*/
	116	void (*pm_idle)(void);
	117	EXPORT_SYMBOL(pm_idle);
	118
	119	void (*pm_power_off)(void);
	120	EXPORT_SYMBOL(pm_power_off);
	121
74617fb6 RP	122	void (*arm_pm_restart)(char str) = arm_machine_restart;
	123	EXPORT_SYMBOL_GPL(arm_pm_restart);
	124
	125
1da177e4 LT	126	/*
	127	* This is our default idle handler. We need to disable
	128	* interrupts here to ensure we don't miss a wakeup call.
	129	*/
84dff1a7	130	static void default_idle(void)
1da177e4	131	{
64c7c8f8 NP	132	if (hlt_counter)
	133	cpu_relax();
	134	else {
	135	local_irq_disable();
	136	if (!need_resched()) {
	137	timer_dyn_reprogram();
	138	arch_idle();
	139	}
	140	local_irq_enable();
2ea83398	141	}
1da177e4 LT	142	}
	143
	144	/*
	145	* The idle thread. We try to conserve power, while trying to keep
	146	* overall latency low. The architecture specific idle is passed
	147	* a value to indicate the level of "idleness" of the system.
	148	*/
	149	void cpu_idle(void)
	150	{
	151	local_fiq_enable();
	152
	153	/* endless idle loop with no priority at all */
	154	while (1) {
	155	void (*idle)(void) = pm_idle;
a054a811 RK	156
	157	#ifdef CONFIG_HOTPLUG_CPU
	158	if (cpu_is_offline(smp_processor_id())) {
	159	leds_event(led_idle_start);
	160	cpu_die();
	161	}
	162	#endif
	163
1da177e4 LT	164	if (!idle)
1da177e4 LT	165	idle = default_idle;
1da177e4	166	leds_event(led_idle_start);
9e4559dd	167	tick_nohz_stop_sched_tick();
1da177e4 LT	168	while (!need_resched())
	169	idle();
	170	leds_event(led_idle_end);
9e4559dd	171	tick_nohz_restart_sched_tick();
5bfb5d69	172	preempt_enable_no_resched();
1da177e4	173	schedule();
5bfb5d69	174	preempt_disable();
1da177e4 LT	175	}
	176	}
	177
	178	static char reboot_mode = 'h';
	179
	180	int __init reboot_setup(char *str)
	181	{
	182	reboot_mode = str[0];
	183	return 1;
	184	}
	185
	186	__setup("reboot=", reboot_setup);
	187
	188	void machine_halt(void)
	189	{
	190	}
	191
1da177e4 LT	192
	193	void machine_power_off(void)
	194	{
	195	if (pm_power_off)
	196	pm_power_off();
	197	}
	198
1da177e4 LT	199	void machine_restart(char * __unused)
1da177e4 LT	200	{
74617fb6	201	arm_pm_restart(reboot_mode);
1da177e4 LT	202	}
1da177e4 LT	203
652a12ef	204	void __show_regs(struct pt_regs *regs)
1da177e4	205	{
154c772e RK	206	unsigned long flags;
154c772e RK	207	char buf[64];
1da177e4	208
154c772e RK	209	printk("CPU: %d %s (%s %.*s)\n",
	210	smp_processor_id(), print_tainted(), init_utsname()->release,
	211	(int)strcspn(init_utsname()->version, " "),
	212	init_utsname()->version);
1da177e4 LT	213	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	214	print_symbol("LR is at %s\n", regs->ARM_lr);
154c772e	215	printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
1da177e4	216	"sp : %08lx ip : %08lx fp : %08lx\n",
154c772e RK	217	regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr,
154c772e RK	218	regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
1da177e4 LT	219	printk("r10: %08lx r9 : %08lx r8 : %08lx\n",
	220	regs->ARM_r10, regs->ARM_r9,
	221	regs->ARM_r8);
	222	printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	223	regs->ARM_r7, regs->ARM_r6,
	224	regs->ARM_r5, regs->ARM_r4);
	225	printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	226	regs->ARM_r3, regs->ARM_r2,
	227	regs->ARM_r1, regs->ARM_r0);
154c772e RK	228
	229	flags = regs->ARM_cpsr;
	230	buf[0] = flags & PSR_N_BIT ? 'N' : 'n';
	231	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	232	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	233	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	234	buf[4] = '\0';
	235
909d6c6c	236	printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n",
154c772e	237	buf, interrupts_enabled(regs) ? "n" : "ff",
1da177e4 LT	238	fast_interrupts_enabled(regs) ? "n" : "ff",
1da177e4 LT	239	processor_modes[processor_mode(regs)],
909d6c6c	240	isa_modes[isa_mode(regs)],
1da177e4	241	get_fs() == get_ds() ? "kernel" : "user");
154c772e	242	#ifdef CONFIG_CPU_CP15
1da177e4	243	{
f12d0d7c	244	unsigned int ctrl;
154c772e RK	245
154c772e RK	246	buf[0] = '\0';
f12d0d7c	247	#ifdef CONFIG_CPU_CP15_MMU
154c772e RK	248	{
	249	unsigned int transbase, dac;
	250	asm("mrc p15, 0, %0, c2, c0\n\t"
	251	"mrc p15, 0, %1, c3, c0\n"
	252	: "=r" (transbase), "=r" (dac));
	253	snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x",
	254	transbase, dac);
	255	}
f12d0d7c	256	#endif
154c772e RK	257	asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl));
	258
	259	printk("Control: %08x%s\n", ctrl, buf);
	260	}
f12d0d7c	261	#endif
1da177e4 LT	262	}
1da177e4 LT	263
652a12ef RK	264	void show_regs(struct pt_regs * regs)
	265	{
	266	printk("\n");
19c5870c	267	printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm);
652a12ef RK	268	__show_regs(regs);
	269	__backtrace();
	270	}
	271
1da177e4 LT	272	void show_fpregs(struct user_fp *regs)
	273	{
	274	int i;
	275
	276	for (i = 0; i < 8; i++) {
	277	unsigned long *p;
	278	char type;
	279
	280	p = (unsigned long *)(regs->fpregs + i);
	281
	282	switch (regs->ftype[i]) {
	283	case 1: type = 'f'; break;
	284	case 2: type = 'd'; break;
	285	case 3: type = 'e'; break;
	286	default: type = '?'; break;
	287	}
	288	if (regs->init_flag)
	289	type = '?';
	290
	291	printk(" f%d(%c): %08lx %08lx %08lx%c",
	292	i, type, p[0], p[1], p[2], i & 1 ? '\n' : ' ');
	293	}
	294
	295
	296	printk("FPSR: %08lx FPCR: %08lx\n",
	297	(unsigned long)regs->fpsr,
	298	(unsigned long)regs->fpcr);
	299	}
	300
1da177e4 LT	301	/*
	302	* Free current thread data structures etc..
	303	*/
	304	void exit_thread(void)
	305	{
	306	}
	307
d6551e88	308	ATOMIC_NOTIFIER_HEAD(thread_notify_head);
1da177e4	309
d6551e88	310	EXPORT_SYMBOL_GPL(thread_notify_head);
1da177e4 LT	311
	312	void flush_thread(void)
	313	{
	314	struct thread_info *thread = current_thread_info();
	315	struct task_struct *tsk = current;
	316
	317	memset(thread->used_cp, 0, sizeof(thread->used_cp));
	318	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
d6551e88 RK	319	memset(&thread->fpstate, 0, sizeof(union fp_state));
	320
	321	thread_notify(THREAD_NOTIFY_FLUSH, thread);
1da177e4 LT	322	}
	323
	324	void release_thread(struct task_struct *dead_task)
	325	{
d6551e88 RK	326	struct thread_info *thread = task_thread_info(dead_task);
	327
	328	thread_notify(THREAD_NOTIFY_RELEASE, thread);
1da177e4 LT	329	}
	330
	331	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
	332
	333	int
	334	copy_thread(int nr, unsigned long clone_flags, unsigned long stack_start,
	335	unsigned long stk_sz, struct task_struct p, struct pt_regs regs)
	336	{
815d5ec8 AV	337	struct thread_info *thread = task_thread_info(p);
815d5ec8 AV	338	struct pt_regs *childregs = task_pt_regs(p);
1da177e4	339
1da177e4 LT	340	childregs = regs;
	341	childregs->ARM_r0 = 0;
	342	childregs->ARM_sp = stack_start;
	343
	344	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
	345	thread->cpu_context.sp = (unsigned long)childregs;
	346	thread->cpu_context.pc = (unsigned long)ret_from_fork;
	347
	348	if (clone_flags & CLONE_SETTLS)
	349	thread->tp_value = regs->ARM_r3;
	350
	351	return 0;
	352	}
	353
	354	/*
	355	* fill in the fpe structure for a core dump...
	356	*/
	357	int dump_fpu (struct pt_regs regs, struct user_fp fp)
	358	{
	359	struct thread_info *thread = current_thread_info();
	360	int used_math = thread->used_cp[1] \| thread->used_cp[2];
	361
	362	if (used_math)
	363	memcpy(fp, &thread->fpstate.soft, sizeof (*fp));
	364
	365	return used_math != 0;
	366	}
	367	EXPORT_SYMBOL(dump_fpu);
	368
1da177e4 LT	369	/*
	370	* Shuffle the argument into the correct register before calling the
	371	* thread function. r1 is the thread argument, r2 is the pointer to
	372	* the thread function, and r3 points to the exit function.
	373	*/
	374	extern void kernel_thread_helper(void);
	375	asm( ".section .text\n"
	376	" .align\n"
	377	" .type kernel_thread_helper, #function\n"
	378	"kernel_thread_helper:\n"
	379	" mov r0, r1\n"
	380	" mov lr, r3\n"
	381	" mov pc, r2\n"
	382	" .size kernel_thread_helper, . - kernel_thread_helper\n"
	383	" .previous");
	384
	385	/*
	386	* Create a kernel thread.
	387	*/
	388	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
	389	{
	390	struct pt_regs regs;
	391
	392	memset(&regs, 0, sizeof(regs));
	393
	394	regs.ARM_r1 = (unsigned long)arg;
	395	regs.ARM_r2 = (unsigned long)fn;
	396	regs.ARM_r3 = (unsigned long)do_exit;
	397	regs.ARM_pc = (unsigned long)kernel_thread_helper;
	398	regs.ARM_cpsr = SVC_MODE;
	399
	400	return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
	401	}
	402	EXPORT_SYMBOL(kernel_thread);
	403
	404	unsigned long get_wchan(struct task_struct *p)
	405	{
	406	unsigned long fp, lr;
4f7a1812	407	unsigned long stack_start, stack_end;
1da177e4 LT	408	int count = 0;
	409	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	410	return 0;
	411
55205823	412	stack_start = (unsigned long)end_of_stack(p);
32d39a93	413	stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE;
4f7a1812	414
1da177e4 LT	415	fp = thread_saved_fp(p);
1da177e4 LT	416	do {
4f7a1812	417	if (fp < stack_start \|\| fp > stack_end)
1da177e4 LT	418	return 0;
	419	lr = pc_pointer (((unsigned long *)fp)[-1]);
	420	if (!in_sched_functions(lr))
	421	return lr;
	422	fp = (unsigned long ) (fp - 12);
	423	} while (count ++ < 16);
	424	return 0;
	425	}