[deliverable/linux.git] / arch / unicore32 / kernel / process.c

/*
 * linux/arch/unicore32/kernel/process.c
 *
 * Code specific to PKUnity SoC and UniCore ISA
 *
 * Copyright (C) 2001-2010 GUAN Xue-tao
 *
 * 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/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/gpio.h>
#include <linux/stacktrace.h>

#include <asm/cacheflush.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/stacktrace.h>

#include "setup.h"

static const char * const processor_modes[] = {
	"UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
	"UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
	"USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
	"UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
};

/*
 * 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.
 */
void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	while (1) {
		tick_nohz_idle_enter_norcu();
		while (!need_resched()) {
			local_irq_disable();
			stop_critical_timings();
			cpu_do_idle();
			local_irq_enable();
			start_critical_timings();
		}
		tick_nohz_idle_exit_norcu();
		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)
{
	gpio_set_value(GPO_SOFT_OFF, 0);
}

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

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

void machine_restart(char *cmd)
{
	/* Disable interrupts first */
	local_irq_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(reboot_mode);

	/* 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();

	/*
	 * Now handle reboot code.
	 */
	if (reboot_mode == 's') {
		/* Jump into ROM at address 0xffff0000 */
		cpu_reset(VECTORS_BASE);
	} else {
		writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
		writel(0x00100800, PM_PLLDDRCFG); /* ddr clk =  44M */
		writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */

		/* Use on-chip reset capability */
		/* following instructions must be in one icache line */
		__asm__ __volatile__(
			"	.align 5\n\t"
			"	stw	%1, [%0]\n\t"
			"201:	ldw	r0, [%0]\n\t"
			"	cmpsub.a	r0, #0\n\t"
			"	bne	201b\n\t"
			"	stw	%3, [%2]\n\t"
			"	nop; nop; nop\n\t"
			/* prefetch 3 instructions at most */
			:
			: "r" (PM_PMCR),
			  "r" (PM_PMCR_CFBSYS | PM_PMCR_CFBDDR
				| PM_PMCR_CFBVGA),
			  "r" (RESETC_SWRR),
			  "r" (RESETC_SWRR_SRB)
			: "r0", "memory");
	}

	/*
	 * Whoops - the architecture was unable to reboot.
	 * Tell the user!
	 */
	mdelay(1000);
	printk(KERN_EMERG "Reboot failed -- System halted\n");
	do { } while (1);
}

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

	printk(KERN_DEFAULT "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->UCreg_lr);
	printk(KERN_DEFAULT "pc : [<%08lx>]    lr : [<%08lx>]    psr: %08lx\n"
	       "sp : %08lx  ip : %08lx  fp : %08lx\n",
		regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
		regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
	printk(KERN_DEFAULT "r26: %08lx  r25: %08lx  r24: %08lx\n",
		regs->UCreg_26, regs->UCreg_25,
		regs->UCreg_24);
	printk(KERN_DEFAULT "r23: %08lx  r22: %08lx  r21: %08lx  r20: %08lx\n",
		regs->UCreg_23, regs->UCreg_22,
		regs->UCreg_21, regs->UCreg_20);
	printk(KERN_DEFAULT "r19: %08lx  r18: %08lx  r17: %08lx  r16: %08lx\n",
		regs->UCreg_19, regs->UCreg_18,
		regs->UCreg_17, regs->UCreg_16);
	printk(KERN_DEFAULT "r15: %08lx  r14: %08lx  r13: %08lx  r12: %08lx\n",
		regs->UCreg_15, regs->UCreg_14,
		regs->UCreg_13, regs->UCreg_12);
	printk(KERN_DEFAULT "r11: %08lx  r10: %08lx  r9 : %08lx  r8 : %08lx\n",
		regs->UCreg_11, regs->UCreg_10,
		regs->UCreg_09, regs->UCreg_08);
	printk(KERN_DEFAULT "r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
		regs->UCreg_07, regs->UCreg_06,
		regs->UCreg_05, regs->UCreg_04);
	printk(KERN_DEFAULT "r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
		regs->UCreg_03, regs->UCreg_02,
		regs->UCreg_01, regs->UCreg_00);

	flags = regs->UCreg_asr;
	buf[0] = flags & PSR_S_BIT ? 'S' : 's';
	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(KERN_DEFAULT "Flags: %s  INTR o%s  REAL o%s  Mode %s  Segment %s\n",
		buf, interrupts_enabled(regs) ? "n" : "ff",
		fast_interrupts_enabled(regs) ? "n" : "ff",
		processor_modes[processor_mode(regs)],
		segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
	{
		unsigned int ctrl;

		buf[0] = '\0';
		{
			unsigned int transbase;
			asm("movc %0, p0.c2, #0\n"
			    : "=r" (transbase));
			snprintf(buf, sizeof(buf), "  Table: %08x", transbase);
		}
		asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));

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

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

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
}

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));
#ifdef CONFIG_UNICORE_FPU_F64
	memset(&thread->fpstate, 0, sizeof(struct fp_state));
#endif
}

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->UCreg_00 = 0;
	childregs->UCreg_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)
		childregs->UCreg_16 = regs->UCreg_03;

	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, elf_fpregset_t *fp)
{
	struct thread_info *thread = current_thread_info();
	int used_math = thread->used_cp[1] | thread->used_cp[2];

#ifdef CONFIG_UNICORE_FPU_F64
	if (used_math)
		memcpy(fp, &thread->fpstate, sizeof(*fp));
#endif
	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.
 */
asm(".pushsection .text\n"
"	.align\n"
"	.type	kernel_thread_helper, #function\n"
"kernel_thread_helper:\n"
"	mov.a	asr, r7\n"
"	mov	r0, r4\n"
"	mov	lr, r6\n"
"	mov	pc, r5\n"
"	.size	kernel_thread_helper, . - kernel_thread_helper\n"
"	.popsection");

/*
 * 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.UCreg_04 = (unsigned long)arg;
	regs.UCreg_05 = (unsigned long)fn;
	regs.UCreg_06 = (unsigned long)do_exit;
	regs.UCreg_07 = PRIV_MODE;
	regs.UCreg_pc = (unsigned long)kernel_thread_helper;
	regs.UCreg_asr = regs.UCreg_07 | 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;
}

/*
 * 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;
}
Commit	Line	Data
f73670e8 G	1	/*
	2	* linux/arch/unicore32/kernel/process.c
	3	*
	4	* Code specific to PKUnity SoC and UniCore ISA
	5	*
	6	* Copyright (C) 2001-2010 GUAN Xue-tao
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12	#include <stdarg.h>
	13
	14	#include <linux/module.h>
	15	#include <linux/sched.h>
	16	#include <linux/kernel.h>
	17	#include <linux/mm.h>
	18	#include <linux/stddef.h>
	19	#include <linux/unistd.h>
	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>
	25	#include <linux/cpu.h>
	26	#include <linux/elfcore.h>
	27	#include <linux/pm.h>
	28	#include <linux/tick.h>
	29	#include <linux/utsname.h>
	30	#include <linux/uaccess.h>
	31	#include <linux/random.h>
	32	#include <linux/gpio.h>
	33	#include <linux/stacktrace.h>
	34
	35	#include <asm/cacheflush.h>
	36	#include <asm/processor.h>
	37	#include <asm/system.h>
	38	#include <asm/stacktrace.h>
	39
	40	#include "setup.h"
	41
	42	static const char * const processor_modes[] = {
	43	"UK00", "UK01", "UK02", "UK03", "UK04", "UK05", "UK06", "UK07",
	44	"UK08", "UK09", "UK0A", "UK0B", "UK0C", "UK0D", "UK0E", "UK0F",
	45	"USER", "REAL", "INTR", "PRIV", "UK14", "UK15", "UK16", "ABRT",
	46	"UK18", "UK19", "UK1A", "EXTN", "UK1C", "UK1D", "UK1E", "SUSR"
	47	};
	48
	49	/*
	50	* The idle thread, has rather strange semantics for calling pm_idle,
	51	* but this is what x86 does and we need to do the same, so that
	52	* things like cpuidle get called in the same way.
	53	*/
	54	void cpu_idle(void)
	55	{
	56	/* endless idle loop with no priority at all */
	57	while (1) {
2bbb6817	58	tick_nohz_idle_enter_norcu();
f73670e8 G	59	while (!need_resched()) {
	60	local_irq_disable();
	61	stop_critical_timings();
	62	cpu_do_idle();
	63	local_irq_enable();
	64	start_critical_timings();
	65	}
2bbb6817	66	tick_nohz_idle_exit_norcu();
f73670e8 G	67	preempt_enable_no_resched();
	68	schedule();
	69	preempt_disable();
	70	}
	71	}
	72
	73	static char reboot_mode = 'h';
	74
	75	int __init reboot_setup(char *str)
	76	{
	77	reboot_mode = str[0];
	78	return 1;
	79	}
	80
	81	__setup("reboot=", reboot_setup);
	82
	83	void machine_halt(void)
	84	{
	85	gpio_set_value(GPO_SOFT_OFF, 0);
	86	}
	87
	88	/*
	89	* Function pointers to optional machine specific functions
	90	*/
	91	void (*pm_power_off)(void) = NULL;
	92
	93	void machine_power_off(void)
	94	{
	95	if (pm_power_off)
	96	pm_power_off();
	97	machine_halt();
	98	}
	99
	100	void machine_restart(char *cmd)
	101	{
	102	/* Disable interrupts first */
	103	local_irq_disable();
	104
	105	/*
	106	* Tell the mm system that we are going to reboot -
	107	* we may need it to insert some 1:1 mappings so that
	108	* soft boot works.
	109	*/
	110	setup_mm_for_reboot(reboot_mode);
	111
	112	/* Clean and invalidate caches */
	113	flush_cache_all();
	114
	115	/* Turn off caching */
	116	cpu_proc_fin();
	117
	118	/* Push out any further dirty data, and ensure cache is empty */
	119	flush_cache_all();
	120
	121	/*
	122	* Now handle reboot code.
	123	*/
	124	if (reboot_mode == 's') {
	125	/* Jump into ROM at address 0xffff0000 */
	126	cpu_reset(VECTORS_BASE);
	127	} else {
e5abf78b G	128	writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
	129	writel(0x00100800, PM_PLLDDRCFG); /* ddr clk = 44M */
	130	writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */
f73670e8 G	131
	132	/* Use on-chip reset capability */
	133	/* following instructions must be in one icache line */
	134	__asm__ __volatile__(
	135	" .align 5\n\t"
	136	" stw %1, [%0]\n\t"
	137	"201: ldw r0, [%0]\n\t"
	138	" cmpsub.a r0, #0\n\t"
	139	" bne 201b\n\t"
	140	" stw %3, [%2]\n\t"
	141	" nop; nop; nop\n\t"
	142	/* prefetch 3 instructions at most */
	143	:
e5abf78b	144	: "r" (PM_PMCR),
f73670e8 G	145	"r" (PM_PMCR_CFBSYS \| PM_PMCR_CFBDDR
f73670e8 G	146	\| PM_PMCR_CFBVGA),
e5abf78b	147	"r" (RESETC_SWRR),
f73670e8 G	148	"r" (RESETC_SWRR_SRB)
	149	: "r0", "memory");
	150	}
	151
	152	/*
	153	* Whoops - the architecture was unable to reboot.
	154	* Tell the user!
	155	*/
	156	mdelay(1000);
	157	printk(KERN_EMERG "Reboot failed -- System halted\n");
	158	do { } while (1);
	159	}
	160
	161	void __show_regs(struct pt_regs *regs)
	162	{
	163	unsigned long flags;
	164	char buf[64];
	165
	166	printk(KERN_DEFAULT "CPU: %d %s (%s %.*s)\n",
	167	raw_smp_processor_id(), print_tainted(),
	168	init_utsname()->release,
	169	(int)strcspn(init_utsname()->version, " "),
	170	init_utsname()->version);
	171	print_symbol("PC is at %s\n", instruction_pointer(regs));
	172	print_symbol("LR is at %s\n", regs->UCreg_lr);
	173	printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
	174	"sp : %08lx ip : %08lx fp : %08lx\n",
	175	regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
	176	regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
	177	printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n",
	178	regs->UCreg_26, regs->UCreg_25,
	179	regs->UCreg_24);
	180	printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
	181	regs->UCreg_23, regs->UCreg_22,
	182	regs->UCreg_21, regs->UCreg_20);
	183	printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
	184	regs->UCreg_19, regs->UCreg_18,
	185	regs->UCreg_17, regs->UCreg_16);
	186	printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
	187	regs->UCreg_15, regs->UCreg_14,
	188	regs->UCreg_13, regs->UCreg_12);
	189	printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
	190	regs->UCreg_11, regs->UCreg_10,
	191	regs->UCreg_09, regs->UCreg_08);
	192	printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	193	regs->UCreg_07, regs->UCreg_06,
	194	regs->UCreg_05, regs->UCreg_04);
	195	printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	196	regs->UCreg_03, regs->UCreg_02,
	197	regs->UCreg_01, regs->UCreg_00);
	198
	199	flags = regs->UCreg_asr;
	200	buf[0] = flags & PSR_S_BIT ? 'S' : 's';
	201	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	202	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	203	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	204	buf[4] = '\0';
	205
	206	printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n",
	207	buf, interrupts_enabled(regs) ? "n" : "ff",
	208	fast_interrupts_enabled(regs) ? "n" : "ff",
	209	processor_modes[processor_mode(regs)],
	210	segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
	211	{
212	unsigned int ctrl;
213
214	buf[0] = '\0';
215	{
216	unsigned int transbase;
217	asm("movc %0, p0.c2, #0\n"
218	: "=r" (transbase));
219	snprintf(buf, sizeof(buf), " Table: %08x", transbase);
220	}
221	asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));
222
223	printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
224	}
225	}
226
227	void show_regs(struct pt_regs *regs)
228	{
229	printk(KERN_DEFAULT "\n");
230	printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
231	task_pid_nr(current), current->comm);
232	__show_regs(regs);
233	__backtrace();
234	}
235
236	/*
237	* Free current thread data structures etc..
238	*/
239	void exit_thread(void)
240	{
241	}
242
243	void flush_thread(void)
244	{
245	struct thread_info *thread = current_thread_info();
246	struct task_struct *tsk = current;
247
248	memset(thread->used_cp, 0, sizeof(thread->used_cp));
249	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
250	#ifdef CONFIG_UNICORE_FPU_F64
251	memset(&thread->fpstate, 0, sizeof(struct fp_state));
252	#endif
253	}
254
255	void release_thread(struct task_struct *dead_task)
256	{
257	}
258
259	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
260
261	int
262	copy_thread(unsigned long clone_flags, unsigned long stack_start,
263	unsigned long stk_sz, struct task_struct p, struct pt_regs regs)
264	{
265	struct thread_info *thread = task_thread_info(p);
266	struct pt_regs *childregs = task_pt_regs(p);
267
268	childregs = regs;
269	childregs->UCreg_00 = 0;
270	childregs->UCreg_sp = stack_start;
271
272	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
273	thread->cpu_context.sp = (unsigned long)childregs;
274	thread->cpu_context.pc = (unsigned long)ret_from_fork;
275
276	if (clone_flags & CLONE_SETTLS)
277	childregs->UCreg_16 = regs->UCreg_03;
278
279	return 0;
280	}
281
282	/*
283	* Fill in the task's elfregs structure for a core dump.
284	*/
285	int dump_task_regs(struct task_struct t, elf_gregset_t elfregs)
286	{
287	elf_core_copy_regs(elfregs, task_pt_regs(t));
288	return 1;
289	}
290
291	/*
292	* fill in the fpe structure for a core dump...
293	*/
294	int dump_fpu(struct pt_regs regs, elf_fpregset_t fp)
295	{
296	struct thread_info *thread = current_thread_info();
297	int used_math = thread->used_cp[1] \| thread->used_cp[2];
298
299	#ifdef CONFIG_UNICORE_FPU_F64
300	if (used_math)
301	memcpy(fp, &thread->fpstate, sizeof(*fp));
302	#endif
303	return used_math != 0;
304	}
305	EXPORT_SYMBOL(dump_fpu);
306
307	/*
308	* Shuffle the argument into the correct register before calling the
309	* thread function. r1 is the thread argument, r2 is the pointer to
310	* the thread function, and r3 points to the exit function.
311	*/
312	asm(".pushsection .text\n"
313	" .align\n"
314	" .type kernel_thread_helper, #function\n"
315	"kernel_thread_helper:\n"
316	" mov.a asr, r7\n"
317	" mov r0, r4\n"
318	" mov lr, r6\n"
319	" mov pc, r5\n"
320	" .size kernel_thread_helper, . - kernel_thread_helper\n"
321	" .popsection");
322
323	/*
324	* Create a kernel thread.
325	*/
326	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
327	{
328	struct pt_regs regs;
329
330	memset(&regs, 0, sizeof(regs));
331
332	regs.UCreg_04 = (unsigned long)arg;
333	regs.UCreg_05 = (unsigned long)fn;
334	regs.UCreg_06 = (unsigned long)do_exit;
335	regs.UCreg_07 = PRIV_MODE;
336	regs.UCreg_pc = (unsigned long)kernel_thread_helper;
337	regs.UCreg_asr = regs.UCreg_07 \| PSR_I_BIT;
338
339	return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
340	}
341	EXPORT_SYMBOL(kernel_thread);
342
343	unsigned long get_wchan(struct task_struct *p)
344	{
345	struct stackframe frame;
346	int count = 0;
347	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
348	return 0;
349
350	frame.fp = thread_saved_fp(p);
351	frame.sp = thread_saved_sp(p);
352	frame.lr = 0; /* recovered from the stack */
353	frame.pc = thread_saved_pc(p);
354	do {
355	int ret = unwind_frame(&frame);
356	if (ret < 0)
357	return 0;
358	if (!in_sched_functions(frame.pc))
359	return frame.pc;
360	} while ((count++) < 16);
361	return 0;
362	}
363
364	unsigned long arch_randomize_brk(struct mm_struct *mm)
365	{
366	unsigned long range_end = mm->brk + 0x02000000;
367	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
368	}
369
370	/*
371	* The vectors page is always readable from user space for the
372	* atomic helpers and the signal restart code. Let's declare a mapping
373	* for it so it is visible through ptrace and /proc/<pid>/mem.
374	*/
375
376	int vectors_user_mapping(void)
377	{
378	struct mm_struct *mm = current->mm;
379	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
380	VM_READ \| VM_EXEC \|
381	VM_MAYREAD \| VM_MAYEXEC \|
382	VM_ALWAYSDUMP \| VM_RESERVED,
383	NULL);
384	}
385
386	const char arch_vma_name(struct vm_area_struct vma)
387	{
388	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
389	}