[deliverable/linux.git] / arch / sh / kernel / process_32.c

/*
 * arch/sh/kernel/process.c
 *
 * This file handles the architecture-dependent parts of process handling..
 *
 *  Copyright (C) 1995  Linus Torvalds
 *
 *  SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
 *		     Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
 *		     Copyright (C) 2002 - 2007  Paul Mundt
 */
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/elfcore.h>
#include <linux/pm.h>
#include <linux/kallsyms.h>
#include <linux/kexec.h>
#include <linux/kdebug.h>
#include <linux/tick.h>
#include <linux/reboot.h>
#include <linux/fs.h>
#include <linux/preempt.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/pgalloc.h>
#include <asm/system.h>
#include <asm/ubc.h>
#include <asm/fpu.h>

static int hlt_counter;
int ubc_usercnt = 0;

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);

static int __init nohlt_setup(char *__unused)
{
	hlt_counter = 1;
	return 1;
}
__setup("nohlt", nohlt_setup);

static int __init hlt_setup(char *__unused)
{
	hlt_counter = 0;
	return 1;
}
__setup("hlt", hlt_setup);

void default_idle(void)
{
	if (!hlt_counter) {
		clear_thread_flag(TIF_POLLING_NRFLAG);
		smp_mb__after_clear_bit();
		set_bl_bit();
		while (!need_resched())
			cpu_sleep();
		clear_bl_bit();
		set_thread_flag(TIF_POLLING_NRFLAG);
	} else
		while (!need_resched())
			cpu_relax();
}

void cpu_idle(void)
{
	set_thread_flag(TIF_POLLING_NRFLAG);

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

		if (!idle)
			idle = default_idle;

		tick_nohz_stop_sched_tick(1);
		while (!need_resched())
			idle();
		tick_nohz_restart_sched_tick();

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

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", task_pid_nr(current), 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");

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

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)childregs;
		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 wrote last, for checking update */
	val = ctrl_inl(UBC_CRR0);

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

#ifdef CONFIG_MMU
	ctrl_outb(asid, UBC_BASRA);
#endif

	ctrl_outl(0, UBC_BAMRA);

	if (current_cpu_data.type == CPU_SH7729 ||
	    current_cpu_data.type == CPU_SH7710 ||
	    current_cpu_data.type == CPU_SH7712) {
		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_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 |= cpu_asid(smp_processor_id(), next->mm);
#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)
{
#ifdef CONFIG_MMU
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	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 __user *ufilename, char __user * __user *uargv,
			  char __user * __user *uenvp, unsigned long r7,
			  struct pt_regs __regs)
{
	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	int error;
	char *filename;

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

	error = do_execve(filename, uargv, 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 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);

#ifdef CONFIG_FRAME_POINTER
	if (in_sched_functions(pc)) {
		unsigned long schedule_frame = (unsigned long)p->thread.sp;
		return ((unsigned long *)schedule_frame)[21];
	}
#endif

	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);
}
Commit	Line	Data
aec5e0e1 PM	1	/*
aec5e0e1 PM	2	* arch/sh/kernel/process.c
1da177e4	3	*
aec5e0e1	4	* This file handles the architecture-dependent parts of process handling..
1da177e4 LT	5	*
	6	* Copyright (C) 1995 Linus Torvalds
	7	*
	8	* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
8ae91b9a	9	* Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
3a2e117e	10	* Copyright (C) 2002 - 2007 Paul Mundt
1da177e4	11	*/
1da177e4	12	#include <linux/module.h>
1da177e4 LT	13	#include <linux/mm.h>
1da177e4 LT	14	#include <linux/elfcore.h>
a3310bbd	15	#include <linux/pm.h>
1da177e4	16	#include <linux/kallsyms.h>
a3310bbd	17	#include <linux/kexec.h>
b118ca57	18	#include <linux/kdebug.h>
57be2b48	19	#include <linux/tick.h>
e08f457c	20	#include <linux/reboot.h>
e06c4e57	21	#include <linux/fs.h>
995bb781	22	#include <linux/preempt.h>
1da177e4 LT	23	#include <asm/uaccess.h>
1da177e4 LT	24	#include <asm/mmu_context.h>
5f8c9908	25	#include <asm/pgalloc.h>
bd079997	26	#include <asm/system.h>
b5233d07	27	#include <asm/ubc.h>
9bbafce2	28	#include <asm/fpu.h>
1da177e4	29
aec5e0e1	30	static int hlt_counter;
1da177e4 LT	31	int ubc_usercnt = 0;
1da177e4 LT	32
a3310bbd	33	void (*pm_idle)(void);
a3310bbd PM	34	void (*pm_power_off)(void);
	35	EXPORT_SYMBOL(pm_power_off);
	36
1da177e4 LT	37	void disable_hlt(void)
	38	{
	39	hlt_counter++;
	40	}
1da177e4 LT	41	EXPORT_SYMBOL(disable_hlt);
	42
	43	void enable_hlt(void)
	44	{
	45	hlt_counter--;
	46	}
1da177e4 LT	47	EXPORT_SYMBOL(enable_hlt);
1da177e4 LT	48
f3a9022f PM	49	static int __init nohlt_setup(char *__unused)
	50	{
	51	hlt_counter = 1;
	52	return 1;
	53	}
	54	__setup("nohlt", nohlt_setup);
	55
	56	static int __init hlt_setup(char *__unused)
	57	{
	58	hlt_counter = 0;
	59	return 1;
	60	}
	61	__setup("hlt", hlt_setup);
	62
a3310bbd PM	63	void default_idle(void)
a3310bbd PM	64	{
f3a9022f PM	65	if (!hlt_counter) {
	66	clear_thread_flag(TIF_POLLING_NRFLAG);
	67	smp_mb__after_clear_bit();
	68	set_bl_bit();
	69	while (!need_resched())
	70	cpu_sleep();
	71	clear_bl_bit();
	72	set_thread_flag(TIF_POLLING_NRFLAG);
	73	} else
	74	while (!need_resched())
	75	cpu_relax();
a3310bbd PM	76	}
a3310bbd PM	77
64c7c8f8	78	void cpu_idle(void)
1da177e4	79	{
f3a9022f PM	80	set_thread_flag(TIF_POLLING_NRFLAG);
f3a9022f PM	81
1da177e4 LT	82	/* endless idle loop with no priority at all */
1da177e4 LT	83	while (1) {
a3310bbd PM	84	void (*idle)(void) = pm_idle;
	85
	86	if (!idle)
	87	idle = default_idle;
	88
b8f8c3cf	89	tick_nohz_stop_sched_tick(1);
a3310bbd PM	90	while (!need_resched())
a3310bbd PM	91	idle();
57be2b48	92	tick_nohz_restart_sched_tick();
1da177e4	93
5bfb5d69	94	preempt_enable_no_resched();
1da177e4	95	schedule();
5bfb5d69	96	preempt_disable();
5f8c9908	97	check_pgt_cache();
1da177e4 LT	98	}
	99	}
	100
1da177e4 LT	101	void machine_restart(char * __unused)
	102	{
	103	/* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
	104	asm volatile("ldc %0, sr\n\t"
	105	"mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
	106	}
	107
1da177e4 LT	108	void machine_halt(void)
1da177e4 LT	109	{
a3310bbd	110	local_irq_disable();
1da177e4	111
1da177e4 LT	112	while (1)
	113	cpu_sleep();
	114	}
	115
1da177e4 LT	116	void machine_power_off(void)
1da177e4 LT	117	{
a3310bbd PM	118	if (pm_power_off)
a3310bbd PM	119	pm_power_off();
1da177e4 LT	120	}
1da177e4 LT	121
1da177e4 LT	122	void show_regs(struct pt_regs * regs)
	123	{
	124	printk("\n");
19c5870c	125	printk("Pid : %d, Comm: %20s\n", task_pid_nr(current), current->comm);
6b002230	126	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	127	printk("PC : %08lx SP : %08lx SR : %08lx ",
	128	regs->pc, regs->regs[15], regs->sr);
	129	#ifdef CONFIG_MMU
	130	printk("TEA : %08x ", ctrl_inl(MMU_TEA));
	131	#else
	132	printk(" ");
	133	#endif
	134	printk("%s\n", print_tainted());
	135
	136	printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
	137	regs->regs[0],regs->regs[1],
	138	regs->regs[2],regs->regs[3]);
	139	printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
	140	regs->regs[4],regs->regs[5],
	141	regs->regs[6],regs->regs[7]);
	142	printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
	143	regs->regs[8],regs->regs[9],
	144	regs->regs[10],regs->regs[11]);
	145	printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
	146	regs->regs[12],regs->regs[13],
	147	regs->regs[14]);
	148	printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
	149	regs->mach, regs->macl, regs->gbr, regs->pr);
	150
6b002230	151	show_trace(NULL, (unsigned long *)regs->regs[15], regs);
1da177e4 LT	152	}
	153
	154	/*
	155	* Create a kernel thread
	156	*/
	157
	158	/*
	159	* This is the mechanism for creating a new kernel thread.
	160	*
	161	*/
	162	extern void kernel_thread_helper(void);
	163	__asm__(".align 5\n"
	164	"kernel_thread_helper:\n\t"
	165	"jsr @r5\n\t"
	166	" nop\n\t"
	167	"mov.l 1f, r1\n\t"
	168	"jsr @r1\n\t"
	169	" mov r0, r4\n\t"
	170	".align 2\n\t"
	171	"1:.long do_exit");
	172
aec5e0e1	173	/* Don't use this in BL=1(cli). Or else, CPU resets! */
1da177e4	174	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
aec5e0e1	175	{
1da177e4 LT	176	struct pt_regs regs;
	177
	178	memset(&regs, 0, sizeof(regs));
aec5e0e1 PM	179	regs.regs[4] = (unsigned long)arg;
aec5e0e1 PM	180	regs.regs[5] = (unsigned long)fn;
1da177e4	181
aec5e0e1	182	regs.pc = (unsigned long)kernel_thread_helper;
1da177e4 LT	183	regs.sr = (1 << 30);
	184
	185	/* Ok, create the new process.. */
aec5e0e1 PM	186	return do_fork(flags \| CLONE_VM \| CLONE_UNTRACED, 0,
aec5e0e1 PM	187	&regs, 0, NULL, NULL);
1da177e4 LT	188	}
	189
	190	/*
	191	* Free current thread data structures etc..
	192	*/
	193	void exit_thread(void)
	194	{
	195	if (current->thread.ubc_pc) {
	196	current->thread.ubc_pc = 0;
	197	ubc_usercnt -= 1;
	198	}
	199	}
	200
	201	void flush_thread(void)
	202	{
	203	#if defined(CONFIG_SH_FPU)
	204	struct task_struct *tsk = current;
1da177e4	205	/* Forget lazy FPU state */
3cf0f4ec	206	clear_fpu(tsk, task_pt_regs(tsk));
1da177e4 LT	207	clear_used_math();
	208	#endif
	209	}
	210
	211	void release_thread(struct task_struct *dead_task)
	212	{
	213	/* do nothing */
	214	}
	215
	216	/* Fill in the fpu structure for a core dump.. */
	217	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu)
	218	{
	219	int fpvalid = 0;
	220
	221	#if defined(CONFIG_SH_FPU)
	222	struct task_struct *tsk = current;
	223
	224	fpvalid = !!tsk_used_math(tsk);
	225	if (fpvalid) {
	226	unlazy_fpu(tsk, regs);
	227	memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
1da177e4 LT	228	}
	229	#endif
	230
	231	return fpvalid;
	232	}
	233
	234	asmlinkage void ret_from_fork(void);
	235
	236	int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
	237	unsigned long unused,
	238	struct task_struct p, struct pt_regs regs)
	239	{
2991be72	240	struct thread_info *ti = task_thread_info(p);
1da177e4 LT	241	struct pt_regs *childregs;
	242	#if defined(CONFIG_SH_FPU)
	243	struct task_struct *tsk = current;
	244
	245	unlazy_fpu(tsk, regs);
	246	p->thread.fpu = tsk->thread.fpu;
	247	copy_to_stopped_child_used_math(p);
	248	#endif
	249
3cf0f4ec	250	childregs = task_pt_regs(p);
1da177e4 LT	251	childregs = regs;
	252
	253	if (user_mode(regs)) {
	254	childregs->regs[15] = usp;
2991be72	255	ti->addr_limit = USER_DS;
1da177e4	256	} else {
e6bcf562	257	childregs->regs[15] = (unsigned long)childregs;
2991be72	258	ti->addr_limit = KERNEL_DS;
1da177e4	259	}
aec5e0e1	260
e6bcf562	261	if (clone_flags & CLONE_SETTLS)
1da177e4	262	childregs->gbr = childregs->regs[0];
aec5e0e1	263
1da177e4 LT	264	childregs->regs[0] = 0; /* Set return value for child */
	265
	266	p->thread.sp = (unsigned long) childregs;
	267	p->thread.pc = (unsigned long) ret_from_fork;
	268
	269	p->thread.ubc_pc = 0;
	270
	271	return 0;
	272	}
	273
1da177e4	274	/* Tracing by user break controller. */
aec5e0e1	275	static void ubc_set_tracing(int asid, unsigned long pc)
1da177e4	276	{
8ae91b9a RS	277	#if defined(CONFIG_CPU_SH4A)
	278	unsigned long val;
	279
	280	val = (UBC_CBR_ID_INST \| UBC_CBR_RW_READ \| UBC_CBR_CE);
	281	val \|= (UBC_CBR_AIE \| UBC_CBR_AIV_SET(asid));
	282
	283	ctrl_outl(val, UBC_CBR0);
	284	ctrl_outl(pc, UBC_CAR0);
	285	ctrl_outl(0x0, UBC_CAMR0);
	286	ctrl_outl(0x0, UBC_CBCR);
	287
	288	val = (UBC_CRR_RES \| UBC_CRR_PCB \| UBC_CRR_BIE);
	289	ctrl_outl(val, UBC_CRR0);
	290
aec5e0e1	291	/* Read UBC register that we wrote last, for checking update */
8ae91b9a RS	292	val = ctrl_inl(UBC_CRR0);
	293
	294	#else /* CONFIG_CPU_SH4A */
1da177e4 LT	295	ctrl_outl(pc, UBC_BARA);
1da177e4 LT	296
a2d1a5fa	297	#ifdef CONFIG_MMU
357d5946	298	ctrl_outb(asid, UBC_BASRA);
a2d1a5fa	299	#endif
1da177e4 LT	300
	301	ctrl_outl(0, UBC_BAMRA);
	302
11c19656	303	if (current_cpu_data.type == CPU_SH7729 \|\|
3a2e117e PM	304	current_cpu_data.type == CPU_SH7710 \|\|
3a2e117e PM	305	current_cpu_data.type == CPU_SH7712) {
1da177e4 LT	306	ctrl_outw(BBR_INST \| BBR_READ \| BBR_CPU, UBC_BBRA);
	307	ctrl_outl(BRCR_PCBA \| BRCR_PCTE, UBC_BRCR);
	308	} else {
	309	ctrl_outw(BBR_INST \| BBR_READ, UBC_BBRA);
	310	ctrl_outw(BRCR_PCBA, UBC_BRCR);
	311	}
8ae91b9a	312	#endif /* CONFIG_CPU_SH4A */
1da177e4 LT	313	}
	314
	315	/*
	316	* switch_to(x,y) should switch tasks from x to y.
	317	*
	318	*/
aec5e0e1 PM	319	struct task_struct __switch_to(struct task_struct prev,
aec5e0e1 PM	320	struct task_struct *next)
1da177e4 LT	321	{
1da177e4 LT	322	#if defined(CONFIG_SH_FPU)
3cf0f4ec	323	unlazy_fpu(prev, task_pt_regs(prev));
1da177e4 LT	324	#endif
1da177e4 LT	325
a2d1a5fa	326	#ifdef CONFIG_MMU
1da177e4 LT	327	/*
1da177e4 LT	328	* Restore the kernel mode register
aec5e0e1	329	* k7 (r7_bank1)
1da177e4 LT	330	*/
	331	asm volatile("ldc %0, r7_bank"
	332	: /* no output */
cafcfcaa	333	: "r" (task_thread_info(next)));
a2d1a5fa	334	#endif
1da177e4	335
1da177e4 LT	336	/* If no tasks are using the UBC, we're done */
	337	if (ubc_usercnt == 0)
	338	/* If no tasks are using the UBC, we're done */;
	339	else if (next->thread.ubc_pc && next->mm) {
a2d1a5fa YS	340	int asid = 0;
a2d1a5fa YS	341	#ifdef CONFIG_MMU
aec5e0e1	342	asid \|= cpu_asid(smp_processor_id(), next->mm);
a2d1a5fa YS	343	#endif
a2d1a5fa YS	344	ubc_set_tracing(asid, next->thread.ubc_pc);
1da177e4	345	} else {
8ae91b9a RS	346	#if defined(CONFIG_CPU_SH4A)
	347	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	348	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
	349	#else
1da177e4 LT	350	ctrl_outw(0, UBC_BBRA);
1da177e4 LT	351	ctrl_outw(0, UBC_BBRB);
8ae91b9a	352	#endif
1da177e4	353	}
1da177e4 LT	354
	355	return prev;
	356	}
	357
	358	asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
	359	unsigned long r6, unsigned long r7,
f0bc814c	360	struct pt_regs __regs)
1da177e4 LT	361	{
1da177e4 LT	362	#ifdef CONFIG_MMU
882c12c4	363	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c	364	return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
1da177e4 LT	365	#else
	366	/* fork almost works, enough to trick you into looking elsewhere :-( */
	367	return -EINVAL;
	368	#endif
	369	}
	370
	371	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
	372	unsigned long parent_tidptr,
	373	unsigned long child_tidptr,
f0bc814c	374	struct pt_regs __regs)
1da177e4	375	{
f0bc814c	376	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4	377	if (!newsp)
f0bc814c SM	378	newsp = regs->regs[15];
f0bc814c SM	379	return do_fork(clone_flags, newsp, regs, 0,
aec5e0e1 PM	380	(int __user *)parent_tidptr,
aec5e0e1 PM	381	(int __user *)child_tidptr);
1da177e4 LT	382	}
	383
	384	/*
	385	* This is trivial, and on the face of it looks like it
	386	* could equally well be done in user mode.
	387	*
	388	* Not so, for quite unobvious reasons - register pressure.
	389	* In user mode vfork() cannot have a stack frame, and if
	390	* done by calling the "clone()" system call directly, you
	391	* do not have enough call-clobbered registers to hold all
	392	* the information you need.
	393	*/
	394	asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
	395	unsigned long r6, unsigned long r7,
f0bc814c	396	struct pt_regs __regs)
1da177e4	397	{
f0bc814c SM	398	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	399	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, regs->regs[15], regs,
1da177e4 LT	400	0, NULL, NULL);
	401	}
	402
	403	/*
	404	* sys_execve() executes a new program.
	405	*/
e08f457c PM	406	asmlinkage int sys_execve(char __user ufilename, char __user __user *uargv,
e08f457c PM	407	char __user * __user *uenvp, unsigned long r7,
f0bc814c	408	struct pt_regs __regs)
1da177e4	409	{
f0bc814c	410	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4 LT	411	int error;
	412	char *filename;
	413
e08f457c	414	filename = getname(ufilename);
1da177e4 LT	415	error = PTR_ERR(filename);
	416	if (IS_ERR(filename))
	417	goto out;
	418
e08f457c	419	error = do_execve(filename, uargv, uenvp, regs);
1da177e4 LT	420	if (error == 0) {
	421	task_lock(current);
	422	current->ptrace &= ~PT_DTRACE;
	423	task_unlock(current);
	424	}
	425	putname(filename);
	426	out:
	427	return error;
	428	}
	429
	430	unsigned long get_wchan(struct task_struct *p)
	431	{
1da177e4 LT	432	unsigned long pc;
	433
	434	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	435	return 0;
	436
	437	/*
	438	* The same comment as on the Alpha applies here, too ...
	439	*/
	440	pc = thread_saved_pc(p);
c64ac9f0 DM	441
c64ac9f0 DM	442	#ifdef CONFIG_FRAME_POINTER
1da177e4	443	if (in_sched_functions(pc)) {
c64ac9f0	444	unsigned long schedule_frame = (unsigned long)p->thread.sp;
b652c23c	445	return ((unsigned long *)schedule_frame)[21];
1da177e4	446	}
c64ac9f0	447	#endif
b652c23c	448
1da177e4 LT	449	return pc;
	450	}
	451
f0bc814c	452	asmlinkage void break_point_trap(void)
1da177e4 LT	453	{
1da177e4 LT	454	/* Clear tracing. */
8ae91b9a RS	455	#if defined(CONFIG_CPU_SH4A)
	456	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	457	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
	458	#else
1da177e4 LT	459	ctrl_outw(0, UBC_BBRA);
1da177e4 LT	460	ctrl_outw(0, UBC_BBRB);
8ae91b9a	461	#endif
1da177e4 LT	462	current->thread.ubc_pc = 0;
	463	ubc_usercnt -= 1;
	464
	465	force_sig(SIGTRAP, current);
	466	}