[net-next-2.6.git] / arch / sh / kernel / process.c

/* $Id: process.c,v 1.28 2004/05/05 16:54:23 lethal Exp $
 *
 *  linux/arch/sh/kernel/process.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 *
 *  SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 *		     Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
 */

/*
 * This file handles the architecture-dependent parts of process handling..
 */

#include <linux/module.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/elfcore.h>
#include <linux/a.out.h>
#include <linux/slab.h>
#include <linux/pm.h>
#include <linux/ptrace.h>
#include <linux/kallsyms.h>
#include <linux/kexec.h>

#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/elf.h>
#include <asm/ubc.h>

static int hlt_counter=0;

int ubc_usercnt = 0;

#define HARD_IDLE_TIMEOUT (HZ / 3)

void (*pm_idle)(void);

void (*pm_power_off)(void);
EXPORT_SYMBOL(pm_power_off);

void disable_hlt(void)
{
	hlt_counter++;
}

EXPORT_SYMBOL(disable_hlt);

void enable_hlt(void)
{
	hlt_counter--;
}

EXPORT_SYMBOL(enable_hlt);

void default_idle(void)
{
	if (!hlt_counter)
		cpu_sleep();
	else
		cpu_relax();
}

void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	while (1) {
		void (*idle)(void) = pm_idle;

		if (!idle)
			idle = default_idle;

		while (!need_resched())
			idle();

		preempt_enable_no_resched();
		schedule();
		preempt_disable();
	}
}

void machine_restart(char * __unused)
{
	/* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
	asm volatile("ldc %0, sr\n\t"
		     "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
}

void machine_halt(void)
{
	local_irq_disable();

	while (1)
		cpu_sleep();
}

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

void show_regs(struct pt_regs * regs)
{
	printk("\n");
	printk("Pid : %d, Comm: %20s\n", current->pid, current->comm);
	print_symbol("PC is at %s\n", instruction_pointer(regs));
	printk("PC  : %08lx SP  : %08lx SR  : %08lx ",
	       regs->pc, regs->regs[15], regs->sr);
#ifdef CONFIG_MMU
	printk("TEA : %08x    ", ctrl_inl(MMU_TEA));
#else
	printk("                  ");
#endif
	printk("%s\n", print_tainted());

	printk("R0  : %08lx R1  : %08lx R2  : %08lx R3  : %08lx\n",
	       regs->regs[0],regs->regs[1],
	       regs->regs[2],regs->regs[3]);
	printk("R4  : %08lx R5  : %08lx R6  : %08lx R7  : %08lx\n",
	       regs->regs[4],regs->regs[5],
	       regs->regs[6],regs->regs[7]);
	printk("R8  : %08lx R9  : %08lx R10 : %08lx R11 : %08lx\n",
	       regs->regs[8],regs->regs[9],
	       regs->regs[10],regs->regs[11]);
	printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
	       regs->regs[12],regs->regs[13],
	       regs->regs[14]);
	printk("MACH: %08lx MACL: %08lx GBR : %08lx PR  : %08lx\n",
	       regs->mach, regs->macl, regs->gbr, regs->pr);

	show_trace(NULL, (unsigned long *)regs->regs[15], regs);
}

/*
 * Create a kernel thread
 */

/*
 * This is the mechanism for creating a new kernel thread.
 *
 */
extern void kernel_thread_helper(void);
__asm__(".align 5\n"
	"kernel_thread_helper:\n\t"
	"jsr	@r5\n\t"
	" nop\n\t"
	"mov.l	1f, r1\n\t"
	"jsr	@r1\n\t"
	" mov	r0, r4\n\t"
	".align 2\n\t"
	"1:.long do_exit");

int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{	/* Don't use this in BL=1(cli).  Or else, CPU resets! */
	struct pt_regs regs;

	memset(&regs, 0, sizeof(regs));
	regs.regs[4] = (unsigned long) arg;
	regs.regs[5] = (unsigned long) fn;

	regs.pc = (unsigned long) kernel_thread_helper;
	regs.sr = (1 << 30);

	/* Ok, create the new process.. */
	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
}

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
	if (current->thread.ubc_pc) {
		current->thread.ubc_pc = 0;
		ubc_usercnt -= 1;
	}
}

void flush_thread(void)
{
#if defined(CONFIG_SH_FPU)
	struct task_struct *tsk = current;
	/* Forget lazy FPU state */
	clear_fpu(tsk, task_pt_regs(tsk));
	clear_used_math();
#endif
}

void release_thread(struct task_struct *dead_task)
{
	/* do nothing */
}

/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
	int fpvalid = 0;

#if defined(CONFIG_SH_FPU)
	struct task_struct *tsk = current;

	fpvalid = !!tsk_used_math(tsk);
	if (fpvalid) {
		unlazy_fpu(tsk, regs);
		memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	}
#endif

	return fpvalid;
}

/* 
 * Capture the user space registers if the task is not running (in user space)
 */
int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
{
	struct pt_regs ptregs;
	
	ptregs = *task_pt_regs(tsk);
	elf_core_copy_regs(regs, &ptregs);

	return 1;
}

int
dump_task_fpu (struct task_struct *tsk, elf_fpregset_t *fpu)
{
	int fpvalid = 0;

#if defined(CONFIG_SH_FPU)
	fpvalid = !!tsk_used_math(tsk);
	if (fpvalid) {
		unlazy_fpu(tsk, task_pt_regs(tsk));
		memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	}
#endif

	return fpvalid;
}

asmlinkage void ret_from_fork(void);

int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
		unsigned long unused,
		struct task_struct *p, struct pt_regs *regs)
{
	struct thread_info *ti = task_thread_info(p);
	struct pt_regs *childregs;
#if defined(CONFIG_SH_FPU)
	struct task_struct *tsk = current;

	unlazy_fpu(tsk, regs);
	p->thread.fpu = tsk->thread.fpu;
	copy_to_stopped_child_used_math(p);
#endif

	childregs = task_pt_regs(p);
	*childregs = *regs;

	if (user_mode(regs)) {
		childregs->regs[15] = usp;
		ti->addr_limit = USER_DS;
	} else {
		childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
		ti->addr_limit = KERNEL_DS;
	}
        if (clone_flags & CLONE_SETTLS) {
		childregs->gbr = childregs->regs[0];
	}
	childregs->regs[0] = 0; /* Set return value for child */

	p->thread.sp = (unsigned long) childregs;
	p->thread.pc = (unsigned long) ret_from_fork;

	p->thread.ubc_pc = 0;

	return 0;
}

/* Tracing by user break controller.  */
static void
ubc_set_tracing(int asid, unsigned long pc)
{
#if defined(CONFIG_CPU_SH4A)
	unsigned long val;

	val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE);
	val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid));

	ctrl_outl(val, UBC_CBR0);
	ctrl_outl(pc,  UBC_CAR0);
	ctrl_outl(0x0, UBC_CAMR0);
	ctrl_outl(0x0, UBC_CBCR);

	val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE);
	ctrl_outl(val, UBC_CRR0);

	/* Read UBC register that we writed last. For chekking UBC Register changed */
	val = ctrl_inl(UBC_CRR0);

#else	/* CONFIG_CPU_SH4A */
	ctrl_outl(pc, UBC_BARA);

#ifdef CONFIG_MMU
	/* We don't have any ASID settings for the SH-2! */
	if (cpu_data->type != CPU_SH7604)
		ctrl_outb(asid, UBC_BASRA);
#endif

	ctrl_outl(0, UBC_BAMRA);

	if (cpu_data->type == CPU_SH7729 || cpu_data->type == CPU_SH7710) {
		ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA);
		ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR);
	} else {
		ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA);
		ctrl_outw(BRCR_PCBA, UBC_BRCR);
	}
#endif	/* CONFIG_CPU_SH4A */
}

/*
 *	switch_to(x,y) should switch tasks from x to y.
 *
 */
struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next)
{
#if defined(CONFIG_SH_FPU)
	unlazy_fpu(prev, task_pt_regs(prev));
#endif

#ifdef CONFIG_PREEMPT
	{
		unsigned long flags;
		struct pt_regs *regs;

		local_irq_save(flags);
		regs = task_pt_regs(prev);
		if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
			int offset = (int)regs->regs[15];

			/* Reset stack pointer: clear critical region mark */
			regs->regs[15] = regs->regs[1];
			if (regs->pc < regs->regs[0])
				/* Go to rewind point */
				regs->pc = regs->regs[0] + offset;
		}
		local_irq_restore(flags);
	}
#endif

#ifdef CONFIG_MMU
	/*
	 * Restore the kernel mode register
	 *   	k7 (r7_bank1)
	 */
	asm volatile("ldc	%0, r7_bank"
		     : /* no output */
		     : "r" (task_thread_info(next)));
#endif

	/* If no tasks are using the UBC, we're done */
	if (ubc_usercnt == 0)
		/* If no tasks are using the UBC, we're done */;
	else if (next->thread.ubc_pc && next->mm) {
		int asid = 0;
#ifdef CONFIG_MMU
		asid |= next->mm->context.id & MMU_CONTEXT_ASID_MASK;
#endif
		ubc_set_tracing(asid, next->thread.ubc_pc);
	} else {
#if defined(CONFIG_CPU_SH4A)
		ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
		ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
#else
		ctrl_outw(0, UBC_BBRA);
		ctrl_outw(0, UBC_BBRB);
#endif
	}

	return prev;
}

asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
			unsigned long r6, unsigned long r7,
			struct pt_regs __regs)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
#ifdef CONFIG_MMU
	return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
#else
	/* fork almost works, enough to trick you into looking elsewhere :-( */
	return -EINVAL;
#endif
}

asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
			 unsigned long parent_tidptr,
			 unsigned long child_tidptr,
			 struct pt_regs __regs)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	if (!newsp)
		newsp = regs->regs[15];
	return do_fork(clone_flags, newsp, regs, 0,
			(int __user *)parent_tidptr, (int __user *)child_tidptr);
}

/*
 * This is trivial, and on the face of it looks like it
 * could equally well be done in user mode.
 *
 * Not so, for quite unobvious reasons - register pressure.
 * In user mode vfork() cannot have a stack frame, and if
 * done by calling the "clone()" system call directly, you
 * do not have enough call-clobbered registers to hold all
 * the information you need.
 */
asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
			 unsigned long r6, unsigned long r7,
			 struct pt_regs __regs)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
		       0, NULL, NULL);
}

/*
 * sys_execve() executes a new program.
 */
asmlinkage int sys_execve(char *ufilename, char **uargv,
			  char **uenvp, unsigned long r7,
			  struct pt_regs __regs)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	int error;
	char *filename;

	filename = getname((char __user *)ufilename);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;

	error = do_execve(filename,
			  (char __user * __user *)uargv,
			  (char __user * __user *)uenvp,
			  regs);
	if (error == 0) {
		task_lock(current);
		current->ptrace &= ~PT_DTRACE;
		task_unlock(current);
	}
	putname(filename);
out:
	return error;
}

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long schedule_frame;
	unsigned long pc;

	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	/*
	 * The same comment as on the Alpha applies here, too ...
	 */
	pc = thread_saved_pc(p);
	if (in_sched_functions(pc)) {
		schedule_frame = ((unsigned long *)(long)p->thread.sp)[1];
		return (unsigned long)((unsigned long *)schedule_frame)[1];
	}
	return pc;
}

asmlinkage void break_point_trap(void)
{
	/* Clear tracing.  */
#if defined(CONFIG_CPU_SH4A)
	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
#else
	ctrl_outw(0, UBC_BBRA);
	ctrl_outw(0, UBC_BBRB);
#endif
	current->thread.ubc_pc = 0;
	ubc_usercnt -= 1;

	force_sig(SIGTRAP, current);
}

asmlinkage void break_point_trap_software(unsigned long r4, unsigned long r5,
					  unsigned long r6, unsigned long r7,
					  struct pt_regs __regs)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);

	/* Rewind */
	regs->pc -= 2;

#ifdef CONFIG_BUG
	if (__kernel_text_address(instruction_pointer(regs))) {
		u16 insn = *(u16 *)instruction_pointer(regs);
		if (insn == TRAPA_BUG_OPCODE)
			handle_BUG(regs);
	}
#endif

	force_sig(SIGTRAP, current);
}
Commit	Line	Data
1da177e4 LT	1	/* $Id: process.c,v 1.28 2004/05/05 16:54:23 lethal Exp $
	2	*
	3	* linux/arch/sh/kernel/process.c
	4	*
	5	* Copyright (C) 1995 Linus Torvalds
	6	*
	7	* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
8ae91b9a	8	* Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
1da177e4 LT	9	*/
	10
	11	/*
	12	* This file handles the architecture-dependent parts of process handling..
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/unistd.h>
	17	#include <linux/mm.h>
	18	#include <linux/elfcore.h>
1da177e4	19	#include <linux/a.out.h>
a3310bbd PM	20	#include <linux/slab.h>
a3310bbd PM	21	#include <linux/pm.h>
1da177e4	22	#include <linux/ptrace.h>
1da177e4	23	#include <linux/kallsyms.h>
a3310bbd	24	#include <linux/kexec.h>
1da177e4 LT	25
	26	#include <asm/io.h>
	27	#include <asm/uaccess.h>
	28	#include <asm/mmu_context.h>
	29	#include <asm/elf.h>
b5233d07	30	#include <asm/ubc.h>
1da177e4 LT	31
	32	static int hlt_counter=0;
	33
	34	int ubc_usercnt = 0;
	35
	36	#define HARD_IDLE_TIMEOUT (HZ / 3)
	37
a3310bbd PM	38	void (*pm_idle)(void);
	39
	40	void (*pm_power_off)(void);
	41	EXPORT_SYMBOL(pm_power_off);
	42
1da177e4 LT	43	void disable_hlt(void)
	44	{
	45	hlt_counter++;
	46	}
	47
	48	EXPORT_SYMBOL(disable_hlt);
	49
	50	void enable_hlt(void)
	51	{
	52	hlt_counter--;
	53	}
	54
	55	EXPORT_SYMBOL(enable_hlt);
	56
a3310bbd PM	57	void default_idle(void)
	58	{
	59	if (!hlt_counter)
	60	cpu_sleep();
	61	else
	62	cpu_relax();
	63	}
	64
64c7c8f8	65	void cpu_idle(void)
1da177e4 LT	66	{
	67	/* endless idle loop with no priority at all */
	68	while (1) {
a3310bbd PM	69	void (*idle)(void) = pm_idle;
	70
	71	if (!idle)
	72	idle = default_idle;
	73
	74	while (!need_resched())
	75	idle();
1da177e4	76
5bfb5d69	77	preempt_enable_no_resched();
1da177e4	78	schedule();
5bfb5d69	79	preempt_disable();
1da177e4 LT	80	}
	81	}
	82
1da177e4 LT	83	void machine_restart(char * __unused)
	84	{
	85	/* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
	86	asm volatile("ldc %0, sr\n\t"
	87	"mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
	88	}
	89
1da177e4 LT	90	void machine_halt(void)
1da177e4 LT	91	{
a3310bbd	92	local_irq_disable();
1da177e4	93
1da177e4 LT	94	while (1)
	95	cpu_sleep();
	96	}
	97
1da177e4 LT	98	void machine_power_off(void)
1da177e4 LT	99	{
a3310bbd PM	100	if (pm_power_off)
a3310bbd PM	101	pm_power_off();
1da177e4 LT	102	}
1da177e4 LT	103
1da177e4 LT	104	void show_regs(struct pt_regs * regs)
	105	{
	106	printk("\n");
	107	printk("Pid : %d, Comm: %20s\n", current->pid, current->comm);
6b002230	108	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	109	printk("PC : %08lx SP : %08lx SR : %08lx ",
	110	regs->pc, regs->regs[15], regs->sr);
	111	#ifdef CONFIG_MMU
	112	printk("TEA : %08x ", ctrl_inl(MMU_TEA));
	113	#else
	114	printk(" ");
	115	#endif
	116	printk("%s\n", print_tainted());
	117
	118	printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
	119	regs->regs[0],regs->regs[1],
	120	regs->regs[2],regs->regs[3]);
	121	printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
	122	regs->regs[4],regs->regs[5],
	123	regs->regs[6],regs->regs[7]);
	124	printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
	125	regs->regs[8],regs->regs[9],
	126	regs->regs[10],regs->regs[11]);
	127	printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
	128	regs->regs[12],regs->regs[13],
	129	regs->regs[14]);
	130	printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
	131	regs->mach, regs->macl, regs->gbr, regs->pr);
	132
6b002230	133	show_trace(NULL, (unsigned long *)regs->regs[15], regs);
1da177e4 LT	134	}
	135
	136	/*
	137	* Create a kernel thread
	138	*/
	139
	140	/*
	141	* This is the mechanism for creating a new kernel thread.
	142	*
	143	*/
	144	extern void kernel_thread_helper(void);
	145	__asm__(".align 5\n"
	146	"kernel_thread_helper:\n\t"
	147	"jsr @r5\n\t"
	148	" nop\n\t"
	149	"mov.l 1f, r1\n\t"
	150	"jsr @r1\n\t"
	151	" mov r0, r4\n\t"
	152	".align 2\n\t"
	153	"1:.long do_exit");
	154
	155	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
	156	{ /* Don't use this in BL=1(cli). Or else, CPU resets! */
	157	struct pt_regs regs;
	158
	159	memset(&regs, 0, sizeof(regs));
	160	regs.regs[4] = (unsigned long) arg;
	161	regs.regs[5] = (unsigned long) fn;
	162
	163	regs.pc = (unsigned long) kernel_thread_helper;
	164	regs.sr = (1 << 30);
	165
	166	/* Ok, create the new process.. */
	167	return do_fork(flags \| CLONE_VM \| CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
	168	}
	169
	170	/*
	171	* Free current thread data structures etc..
	172	*/
	173	void exit_thread(void)
	174	{
	175	if (current->thread.ubc_pc) {
	176	current->thread.ubc_pc = 0;
	177	ubc_usercnt -= 1;
	178	}
	179	}
	180
	181	void flush_thread(void)
	182	{
	183	#if defined(CONFIG_SH_FPU)
	184	struct task_struct *tsk = current;
1da177e4	185	/* Forget lazy FPU state */
3cf0f4ec	186	clear_fpu(tsk, task_pt_regs(tsk));
1da177e4 LT	187	clear_used_math();
	188	#endif
	189	}
	190
	191	void release_thread(struct task_struct *dead_task)
	192	{
	193	/* do nothing */
	194	}
	195
	196	/* Fill in the fpu structure for a core dump.. */
	197	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu)
	198	{
	199	int fpvalid = 0;
	200
	201	#if defined(CONFIG_SH_FPU)
	202	struct task_struct *tsk = current;
	203
	204	fpvalid = !!tsk_used_math(tsk);
	205	if (fpvalid) {
	206	unlazy_fpu(tsk, regs);
	207	memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	208	}
	209	#endif
	210
	211	return fpvalid;
	212	}
	213
	214	/*
	215	* Capture the user space registers if the task is not running (in user space)
	216	*/
	217	int dump_task_regs(struct task_struct tsk, elf_gregset_t regs)
	218	{
	219	struct pt_regs ptregs;
	220
3cf0f4ec	221	ptregs = *task_pt_regs(tsk);
1da177e4 LT	222	elf_core_copy_regs(regs, &ptregs);
	223
	224	return 1;
	225	}
	226
	227	int
	228	dump_task_fpu (struct task_struct tsk, elf_fpregset_t fpu)
	229	{
	230	int fpvalid = 0;
	231
	232	#if defined(CONFIG_SH_FPU)
	233	fpvalid = !!tsk_used_math(tsk);
	234	if (fpvalid) {
3cf0f4ec	235	unlazy_fpu(tsk, task_pt_regs(tsk));
1da177e4 LT	236	memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	237	}
	238	#endif
	239
	240	return fpvalid;
	241	}
	242
	243	asmlinkage void ret_from_fork(void);
	244
	245	int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
	246	unsigned long unused,
	247	struct task_struct p, struct pt_regs regs)
	248	{
2991be72	249	struct thread_info *ti = task_thread_info(p);
1da177e4 LT	250	struct pt_regs *childregs;
	251	#if defined(CONFIG_SH_FPU)
	252	struct task_struct *tsk = current;
	253
	254	unlazy_fpu(tsk, regs);
	255	p->thread.fpu = tsk->thread.fpu;
	256	copy_to_stopped_child_used_math(p);
	257	#endif
	258
3cf0f4ec	259	childregs = task_pt_regs(p);
1da177e4 LT	260	childregs = regs;
	261
	262	if (user_mode(regs)) {
	263	childregs->regs[15] = usp;
2991be72	264	ti->addr_limit = USER_DS;
1da177e4	265	} else {
308a792f	266	childregs->regs[15] = (unsigned long)task_stack_page(p) + THREAD_SIZE;
2991be72	267	ti->addr_limit = KERNEL_DS;
1da177e4 LT	268	}
	269	if (clone_flags & CLONE_SETTLS) {
	270	childregs->gbr = childregs->regs[0];
	271	}
	272	childregs->regs[0] = 0; /* Set return value for child */
	273
	274	p->thread.sp = (unsigned long) childregs;
	275	p->thread.pc = (unsigned long) ret_from_fork;
	276
	277	p->thread.ubc_pc = 0;
	278
	279	return 0;
	280	}
	281
1da177e4 LT	282	/* Tracing by user break controller. */
	283	static void
	284	ubc_set_tracing(int asid, unsigned long pc)
	285	{
8ae91b9a RS	286	#if defined(CONFIG_CPU_SH4A)
	287	unsigned long val;
	288
	289	val = (UBC_CBR_ID_INST \| UBC_CBR_RW_READ \| UBC_CBR_CE);
	290	val \|= (UBC_CBR_AIE \| UBC_CBR_AIV_SET(asid));
	291
	292	ctrl_outl(val, UBC_CBR0);
	293	ctrl_outl(pc, UBC_CAR0);
	294	ctrl_outl(0x0, UBC_CAMR0);
	295	ctrl_outl(0x0, UBC_CBCR);
	296
	297	val = (UBC_CRR_RES \| UBC_CRR_PCB \| UBC_CRR_BIE);
	298	ctrl_outl(val, UBC_CRR0);
	299
	300	/* Read UBC register that we writed last. For chekking UBC Register changed */
	301	val = ctrl_inl(UBC_CRR0);
	302
	303	#else /* CONFIG_CPU_SH4A */
1da177e4 LT	304	ctrl_outl(pc, UBC_BARA);
1da177e4 LT	305
a2d1a5fa	306	#ifdef CONFIG_MMU
1da177e4 LT	307	/* We don't have any ASID settings for the SH-2! */
	308	if (cpu_data->type != CPU_SH7604)
	309	ctrl_outb(asid, UBC_BASRA);
a2d1a5fa	310	#endif
1da177e4 LT	311
	312	ctrl_outl(0, UBC_BAMRA);
	313
e5723e0e	314	if (cpu_data->type == CPU_SH7729 \|\| cpu_data->type == CPU_SH7710) {
1da177e4 LT	315	ctrl_outw(BBR_INST \| BBR_READ \| BBR_CPU, UBC_BBRA);
	316	ctrl_outl(BRCR_PCBA \| BRCR_PCTE, UBC_BRCR);
	317	} else {
	318	ctrl_outw(BBR_INST \| BBR_READ, UBC_BBRA);
	319	ctrl_outw(BRCR_PCBA, UBC_BRCR);
	320	}
8ae91b9a	321	#endif /* CONFIG_CPU_SH4A */
1da177e4 LT	322	}
	323
	324	/*
	325	* switch_to(x,y) should switch tasks from x to y.
	326	*
	327	*/
	328	struct task_struct __switch_to(struct task_struct prev, struct task_struct *next)
	329	{
	330	#if defined(CONFIG_SH_FPU)
3cf0f4ec	331	unlazy_fpu(prev, task_pt_regs(prev));
1da177e4 LT	332	#endif
	333
	334	#ifdef CONFIG_PREEMPT
	335	{
	336	unsigned long flags;
	337	struct pt_regs *regs;
	338
	339	local_irq_save(flags);
3cf0f4ec	340	regs = task_pt_regs(prev);
1da177e4 LT	341	if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
	342	int offset = (int)regs->regs[15];
	343
	344	/* Reset stack pointer: clear critical region mark */
	345	regs->regs[15] = regs->regs[1];
	346	if (regs->pc < regs->regs[0])
	347	/* Go to rewind point */
	348	regs->pc = regs->regs[0] + offset;
	349	}
	350	local_irq_restore(flags);
	351	}
	352	#endif
	353
a2d1a5fa	354	#ifdef CONFIG_MMU
1da177e4 LT	355	/*
	356	* Restore the kernel mode register
	357	* k7 (r7_bank1)
	358	*/
	359	asm volatile("ldc %0, r7_bank"
	360	: /* no output */
cafcfcaa	361	: "r" (task_thread_info(next)));
a2d1a5fa	362	#endif
1da177e4	363
1da177e4 LT	364	/* If no tasks are using the UBC, we're done */
	365	if (ubc_usercnt == 0)
	366	/* If no tasks are using the UBC, we're done */;
	367	else if (next->thread.ubc_pc && next->mm) {
a2d1a5fa YS	368	int asid = 0;
a2d1a5fa YS	369	#ifdef CONFIG_MMU
19f9a34f	370	asid \|= next->mm->context.id & MMU_CONTEXT_ASID_MASK;
a2d1a5fa YS	371	#endif
a2d1a5fa YS	372	ubc_set_tracing(asid, next->thread.ubc_pc);
1da177e4	373	} else {
8ae91b9a RS	374	#if defined(CONFIG_CPU_SH4A)
	375	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	376	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
	377	#else
1da177e4 LT	378	ctrl_outw(0, UBC_BBRA);
1da177e4 LT	379	ctrl_outw(0, UBC_BBRB);
8ae91b9a	380	#endif
1da177e4	381	}
1da177e4 LT	382
	383	return prev;
	384	}
	385
	386	asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
	387	unsigned long r6, unsigned long r7,
f0bc814c	388	struct pt_regs __regs)
1da177e4	389	{
f0bc814c	390	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4	391	#ifdef CONFIG_MMU
f0bc814c	392	return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
1da177e4 LT	393	#else
	394	/* fork almost works, enough to trick you into looking elsewhere :-( */
	395	return -EINVAL;
	396	#endif
	397	}
	398
	399	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
	400	unsigned long parent_tidptr,
	401	unsigned long child_tidptr,
f0bc814c	402	struct pt_regs __regs)
1da177e4	403	{
f0bc814c	404	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4	405	if (!newsp)
f0bc814c SM	406	newsp = regs->regs[15];
f0bc814c SM	407	return do_fork(clone_flags, newsp, regs, 0,
1da177e4 LT	408	(int __user )parent_tidptr, (int __user )child_tidptr);
	409	}
	410
	411	/*
	412	* This is trivial, and on the face of it looks like it
	413	* could equally well be done in user mode.
	414	*
	415	* Not so, for quite unobvious reasons - register pressure.
	416	* In user mode vfork() cannot have a stack frame, and if
	417	* done by calling the "clone()" system call directly, you
	418	* do not have enough call-clobbered registers to hold all
	419	* the information you need.
	420	*/
	421	asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
	422	unsigned long r6, unsigned long r7,
f0bc814c	423	struct pt_regs __regs)
1da177e4	424	{
f0bc814c SM	425	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	426	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, regs->regs[15], regs,
1da177e4 LT	427	0, NULL, NULL);
	428	}
	429
	430	/*
	431	* sys_execve() executes a new program.
	432	*/
	433	asmlinkage int sys_execve(char ufilename, char *uargv,
	434	char **uenvp, unsigned long r7,
f0bc814c	435	struct pt_regs __regs)
1da177e4	436	{
f0bc814c	437	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4 LT	438	int error;
	439	char *filename;
	440
	441	filename = getname((char __user *)ufilename);
	442	error = PTR_ERR(filename);
	443	if (IS_ERR(filename))
	444	goto out;
	445
	446	error = do_execve(filename,
	447	(char __user * __user *)uargv,
	448	(char __user * __user *)uenvp,
f0bc814c	449	regs);
1da177e4 LT	450	if (error == 0) {
	451	task_lock(current);
	452	current->ptrace &= ~PT_DTRACE;
	453	task_unlock(current);
	454	}
	455	putname(filename);
	456	out:
	457	return error;
	458	}
	459
	460	unsigned long get_wchan(struct task_struct *p)
	461	{
	462	unsigned long schedule_frame;
	463	unsigned long pc;
	464
	465	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	466	return 0;
	467
	468	/*
	469	* The same comment as on the Alpha applies here, too ...
	470	*/
	471	pc = thread_saved_pc(p);
	472	if (in_sched_functions(pc)) {
	473	schedule_frame = ((unsigned long *)(long)p->thread.sp)[1];
	474	return (unsigned long)((unsigned long *)schedule_frame)[1];
	475	}
	476	return pc;
	477	}
	478
f0bc814c	479	asmlinkage void break_point_trap(void)
1da177e4 LT	480	{
1da177e4 LT	481	/* Clear tracing. */
8ae91b9a RS	482	#if defined(CONFIG_CPU_SH4A)
	483	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	484	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
	485	#else
1da177e4 LT	486	ctrl_outw(0, UBC_BBRA);
1da177e4 LT	487	ctrl_outw(0, UBC_BBRB);
8ae91b9a	488	#endif
1da177e4 LT	489	current->thread.ubc_pc = 0;
	490	ubc_usercnt -= 1;
	491
	492	force_sig(SIGTRAP, current);
	493	}
	494
	495	asmlinkage void break_point_trap_software(unsigned long r4, unsigned long r5,
	496	unsigned long r6, unsigned long r7,
f0bc814c	497	struct pt_regs __regs)
1da177e4	498	{
f0bc814c SM	499	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	500
dc34d312	501	/* Rewind */
f0bc814c	502	regs->pc -= 2;
dc34d312 PM	503
	504	#ifdef CONFIG_BUG
	505	if (__kernel_text_address(instruction_pointer(regs))) {
	506	u16 insn = (u16 )instruction_pointer(regs);
	507	if (insn == TRAPA_BUG_OPCODE)
	508	handle_BUG(regs);
	509	}
	510	#endif
	511
1da177e4 LT	512	force_sig(SIGTRAP, current);
1da177e4 LT	513	}