[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();
		rcu_idle_enter();
		while (!need_resched()) {
			local_irq_disable();
			stop_critical_timings();
			cpu_do_idle();
			local_irq_enable();
			start_critical_timings();
		}
		rcu_idle_exit();
		tick_nohz_idle_exit();
		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) {
1268fbc7 FW	58	tick_nohz_idle_enter();
1268fbc7 FW	59	rcu_idle_enter();
f73670e8 G	60	while (!need_resched()) {
	61	local_irq_disable();
	62	stop_critical_timings();
	63	cpu_do_idle();
	64	local_irq_enable();
	65	start_critical_timings();
	66	}
1268fbc7 FW	67	rcu_idle_exit();
1268fbc7 FW	68	tick_nohz_idle_exit();
f73670e8 G	69	preempt_enable_no_resched();
	70	schedule();
	71	preempt_disable();
	72	}
	73	}
	74
	75	static char reboot_mode = 'h';
	76
	77	int __init reboot_setup(char *str)
	78	{
	79	reboot_mode = str[0];
	80	return 1;
	81	}
	82
	83	__setup("reboot=", reboot_setup);
	84
	85	void machine_halt(void)
	86	{
	87	gpio_set_value(GPO_SOFT_OFF, 0);
	88	}
	89
	90	/*
	91	* Function pointers to optional machine specific functions
	92	*/
	93	void (*pm_power_off)(void) = NULL;
	94
	95	void machine_power_off(void)
	96	{
	97	if (pm_power_off)
	98	pm_power_off();
	99	machine_halt();
	100	}
	101
	102	void machine_restart(char *cmd)
	103	{
	104	/* Disable interrupts first */
	105	local_irq_disable();
	106
	107	/*
	108	* Tell the mm system that we are going to reboot -
	109	* we may need it to insert some 1:1 mappings so that
	110	* soft boot works.
	111	*/
	112	setup_mm_for_reboot(reboot_mode);
	113
	114	/* Clean and invalidate caches */
	115	flush_cache_all();
	116
	117	/* Turn off caching */
	118	cpu_proc_fin();
	119
	120	/* Push out any further dirty data, and ensure cache is empty */
	121	flush_cache_all();
	122
	123	/*
	124	* Now handle reboot code.
	125	*/
	126	if (reboot_mode == 's') {
	127	/* Jump into ROM at address 0xffff0000 */
	128	cpu_reset(VECTORS_BASE);
	129	} else {
e5abf78b G	130	writel(0x00002001, PM_PLLSYSCFG); /* cpu clk = 250M */
	131	writel(0x00100800, PM_PLLDDRCFG); /* ddr clk = 44M */
	132	writel(0x00002001, PM_PLLVGACFG); /* vga clk = 250M */
f73670e8 G	133
	134	/* Use on-chip reset capability */
	135	/* following instructions must be in one icache line */
	136	__asm__ __volatile__(
	137	" .align 5\n\t"
	138	" stw %1, [%0]\n\t"
	139	"201: ldw r0, [%0]\n\t"
	140	" cmpsub.a r0, #0\n\t"
	141	" bne 201b\n\t"
	142	" stw %3, [%2]\n\t"
	143	" nop; nop; nop\n\t"
	144	/* prefetch 3 instructions at most */
	145	:
e5abf78b	146	: "r" (PM_PMCR),
f73670e8 G	147	"r" (PM_PMCR_CFBSYS \| PM_PMCR_CFBDDR
f73670e8 G	148	\| PM_PMCR_CFBVGA),
e5abf78b	149	"r" (RESETC_SWRR),
f73670e8 G	150	"r" (RESETC_SWRR_SRB)
	151	: "r0", "memory");
	152	}
	153
	154	/*
	155	* Whoops - the architecture was unable to reboot.
	156	* Tell the user!
	157	*/
	158	mdelay(1000);
	159	printk(KERN_EMERG "Reboot failed -- System halted\n");
	160	do { } while (1);
	161	}
	162
	163	void __show_regs(struct pt_regs *regs)
	164	{
	165	unsigned long flags;
	166	char buf[64];
	167
	168	printk(KERN_DEFAULT "CPU: %d %s (%s %.*s)\n",
	169	raw_smp_processor_id(), print_tainted(),
	170	init_utsname()->release,
	171	(int)strcspn(init_utsname()->version, " "),
	172	init_utsname()->version);
	173	print_symbol("PC is at %s\n", instruction_pointer(regs));
	174	print_symbol("LR is at %s\n", regs->UCreg_lr);
	175	printk(KERN_DEFAULT "pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n"
	176	"sp : %08lx ip : %08lx fp : %08lx\n",
	177	regs->UCreg_pc, regs->UCreg_lr, regs->UCreg_asr,
	178	regs->UCreg_sp, regs->UCreg_ip, regs->UCreg_fp);
	179	printk(KERN_DEFAULT "r26: %08lx r25: %08lx r24: %08lx\n",
	180	regs->UCreg_26, regs->UCreg_25,
	181	regs->UCreg_24);
	182	printk(KERN_DEFAULT "r23: %08lx r22: %08lx r21: %08lx r20: %08lx\n",
	183	regs->UCreg_23, regs->UCreg_22,
	184	regs->UCreg_21, regs->UCreg_20);
	185	printk(KERN_DEFAULT "r19: %08lx r18: %08lx r17: %08lx r16: %08lx\n",
	186	regs->UCreg_19, regs->UCreg_18,
	187	regs->UCreg_17, regs->UCreg_16);
	188	printk(KERN_DEFAULT "r15: %08lx r14: %08lx r13: %08lx r12: %08lx\n",
	189	regs->UCreg_15, regs->UCreg_14,
	190	regs->UCreg_13, regs->UCreg_12);
	191	printk(KERN_DEFAULT "r11: %08lx r10: %08lx r9 : %08lx r8 : %08lx\n",
	192	regs->UCreg_11, regs->UCreg_10,
	193	regs->UCreg_09, regs->UCreg_08);
	194	printk(KERN_DEFAULT "r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
	195	regs->UCreg_07, regs->UCreg_06,
	196	regs->UCreg_05, regs->UCreg_04);
	197	printk(KERN_DEFAULT "r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
	198	regs->UCreg_03, regs->UCreg_02,
	199	regs->UCreg_01, regs->UCreg_00);
	200
	201	flags = regs->UCreg_asr;
	202	buf[0] = flags & PSR_S_BIT ? 'S' : 's';
	203	buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z';
	204	buf[2] = flags & PSR_C_BIT ? 'C' : 'c';
	205	buf[3] = flags & PSR_V_BIT ? 'V' : 'v';
	206	buf[4] = '\0';
	207
	208	printk(KERN_DEFAULT "Flags: %s INTR o%s REAL o%s Mode %s Segment %s\n",
	209	buf, interrupts_enabled(regs) ? "n" : "ff",
	210	fast_interrupts_enabled(regs) ? "n" : "ff",
	211	processor_modes[processor_mode(regs)],
	212	segment_eq(get_fs(), get_ds()) ? "kernel" : "user");
	213	{
214	unsigned int ctrl;
215
216	buf[0] = '\0';
217	{
218	unsigned int transbase;
219	asm("movc %0, p0.c2, #0\n"
220	: "=r" (transbase));
221	snprintf(buf, sizeof(buf), " Table: %08x", transbase);
222	}
223	asm("movc %0, p0.c1, #0\n" : "=r" (ctrl));
224
225	printk(KERN_DEFAULT "Control: %08x%s\n", ctrl, buf);
226	}
227	}
228
229	void show_regs(struct pt_regs *regs)
230	{
231	printk(KERN_DEFAULT "\n");
232	printk(KERN_DEFAULT "Pid: %d, comm: %20s\n",
233	task_pid_nr(current), current->comm);
234	__show_regs(regs);
235	__backtrace();
236	}
237
238	/*
239	* Free current thread data structures etc..
240	*/
241	void exit_thread(void)
242	{
243	}
244
245	void flush_thread(void)
246	{
247	struct thread_info *thread = current_thread_info();
248	struct task_struct *tsk = current;
249
250	memset(thread->used_cp, 0, sizeof(thread->used_cp));
251	memset(&tsk->thread.debug, 0, sizeof(struct debug_info));
252	#ifdef CONFIG_UNICORE_FPU_F64
253	memset(&thread->fpstate, 0, sizeof(struct fp_state));
254	#endif
255	}
256
257	void release_thread(struct task_struct *dead_task)
258	{
259	}
260
261	asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
262
263	int
264	copy_thread(unsigned long clone_flags, unsigned long stack_start,
265	unsigned long stk_sz, struct task_struct p, struct pt_regs regs)
266	{
267	struct thread_info *thread = task_thread_info(p);
268	struct pt_regs *childregs = task_pt_regs(p);
269
270	childregs = regs;
271	childregs->UCreg_00 = 0;
272	childregs->UCreg_sp = stack_start;
273
274	memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save));
275	thread->cpu_context.sp = (unsigned long)childregs;
276	thread->cpu_context.pc = (unsigned long)ret_from_fork;
277
278	if (clone_flags & CLONE_SETTLS)
279	childregs->UCreg_16 = regs->UCreg_03;
280
281	return 0;
282	}
283
284	/*
285	* Fill in the task's elfregs structure for a core dump.
286	*/
287	int dump_task_regs(struct task_struct t, elf_gregset_t elfregs)
288	{
289	elf_core_copy_regs(elfregs, task_pt_regs(t));
290	return 1;
291	}
292
293	/*
294	* fill in the fpe structure for a core dump...
295	*/
296	int dump_fpu(struct pt_regs regs, elf_fpregset_t fp)
297	{
298	struct thread_info *thread = current_thread_info();
299	int used_math = thread->used_cp[1] \| thread->used_cp[2];
300
301	#ifdef CONFIG_UNICORE_FPU_F64
302	if (used_math)
303	memcpy(fp, &thread->fpstate, sizeof(*fp));
304	#endif
305	return used_math != 0;
306	}
307	EXPORT_SYMBOL(dump_fpu);
308
309	/*
310	* Shuffle the argument into the correct register before calling the
311	* thread function. r1 is the thread argument, r2 is the pointer to
312	* the thread function, and r3 points to the exit function.
313	*/
314	asm(".pushsection .text\n"
315	" .align\n"
316	" .type kernel_thread_helper, #function\n"
317	"kernel_thread_helper:\n"
318	" mov.a asr, r7\n"
319	" mov r0, r4\n"
320	" mov lr, r6\n"
321	" mov pc, r5\n"
322	" .size kernel_thread_helper, . - kernel_thread_helper\n"
323	" .popsection");
324
325	/*
326	* Create a kernel thread.
327	*/
328	pid_t kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
329	{
330	struct pt_regs regs;
331
332	memset(&regs, 0, sizeof(regs));
333
334	regs.UCreg_04 = (unsigned long)arg;
335	regs.UCreg_05 = (unsigned long)fn;
336	regs.UCreg_06 = (unsigned long)do_exit;
337	regs.UCreg_07 = PRIV_MODE;
338	regs.UCreg_pc = (unsigned long)kernel_thread_helper;
339	regs.UCreg_asr = regs.UCreg_07 \| PSR_I_BIT;
340
341	return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
342	}
343	EXPORT_SYMBOL(kernel_thread);
344
345	unsigned long get_wchan(struct task_struct *p)
346	{
347	struct stackframe frame;
348	int count = 0;
349	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
350	return 0;
351
352	frame.fp = thread_saved_fp(p);
353	frame.sp = thread_saved_sp(p);
354	frame.lr = 0; /* recovered from the stack */
355	frame.pc = thread_saved_pc(p);
356	do {
357	int ret = unwind_frame(&frame);
358	if (ret < 0)
359	return 0;
360	if (!in_sched_functions(frame.pc))
361	return frame.pc;
362	} while ((count++) < 16);
363	return 0;
364	}
365
366	unsigned long arch_randomize_brk(struct mm_struct *mm)
367	{
368	unsigned long range_end = mm->brk + 0x02000000;
369	return randomize_range(mm->brk, range_end, 0) ? : mm->brk;
370	}
371
372	/*
373	* The vectors page is always readable from user space for the
374	* atomic helpers and the signal restart code. Let's declare a mapping
375	* for it so it is visible through ptrace and /proc/<pid>/mem.
376	*/
377
378	int vectors_user_mapping(void)
379	{
380	struct mm_struct *mm = current->mm;
381	return install_special_mapping(mm, 0xffff0000, PAGE_SIZE,
382	VM_READ \| VM_EXEC \|
383	VM_MAYREAD \| VM_MAYEXEC \|
384	VM_ALWAYSDUMP \| VM_RESERVED,
385	NULL);
386	}
387
388	const char arch_vma_name(struct vm_area_struct vma)
389	{
390	return (vma->vm_start == 0xffff0000) ? "[vectors]" : NULL;
391	}