[deliverable/linux.git] / arch / sh / kernel / process.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 <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/pgalloc.h>
#include <asm/system.h>
#include <asm/ubc.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();
		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", 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");

/* 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;
}

/*
 * 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)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_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 |= 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);
}

/*
 * Generic trap handler.
 */
asmlinkage void debug_trap_handler(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 -= instruction_size(ctrl_inw(regs->pc - 4));

	if (notify_die(DIE_TRAP, "debug trap", regs, 0, regs->tra & 0xff,
		       SIGTRAP) == NOTIFY_STOP)
		return;

	force_sig(SIGTRAP, current);
}

/*
 * Special handler for BUG() traps.
 */
asmlinkage void bug_trap_handler(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 -= instruction_size(ctrl_inw(regs->pc - 4));

	if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
		       SIGTRAP) == NOTIFY_STOP)
		return;

#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
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>
1da177e4 LT	22	#include <asm/uaccess.h>
1da177e4 LT	23	#include <asm/mmu_context.h>
5f8c9908	24	#include <asm/pgalloc.h>
bd079997	25	#include <asm/system.h>
b5233d07	26	#include <asm/ubc.h>
1da177e4	27
aec5e0e1	28	static int hlt_counter;
1da177e4 LT	29	int ubc_usercnt = 0;
1da177e4 LT	30
a3310bbd	31	void (*pm_idle)(void);
a3310bbd PM	32	void (*pm_power_off)(void);
	33	EXPORT_SYMBOL(pm_power_off);
	34
1da177e4 LT	35	void disable_hlt(void)
	36	{
	37	hlt_counter++;
	38	}
1da177e4 LT	39	EXPORT_SYMBOL(disable_hlt);
	40
	41	void enable_hlt(void)
	42	{
	43	hlt_counter--;
	44	}
1da177e4 LT	45	EXPORT_SYMBOL(enable_hlt);
1da177e4 LT	46
f3a9022f PM	47	static int __init nohlt_setup(char *__unused)
	48	{
	49	hlt_counter = 1;
	50	return 1;
	51	}
	52	__setup("nohlt", nohlt_setup);
	53
	54	static int __init hlt_setup(char *__unused)
	55	{
	56	hlt_counter = 0;
	57	return 1;
	58	}
	59	__setup("hlt", hlt_setup);
	60
a3310bbd PM	61	void default_idle(void)
a3310bbd PM	62	{
f3a9022f PM	63	if (!hlt_counter) {
	64	clear_thread_flag(TIF_POLLING_NRFLAG);
	65	smp_mb__after_clear_bit();
	66	set_bl_bit();
	67	while (!need_resched())
	68	cpu_sleep();
	69	clear_bl_bit();
	70	set_thread_flag(TIF_POLLING_NRFLAG);
	71	} else
	72	while (!need_resched())
	73	cpu_relax();
a3310bbd PM	74	}
a3310bbd PM	75
64c7c8f8	76	void cpu_idle(void)
1da177e4	77	{
f3a9022f PM	78	set_thread_flag(TIF_POLLING_NRFLAG);
f3a9022f PM	79
1da177e4 LT	80	/* endless idle loop with no priority at all */
1da177e4 LT	81	while (1) {
a3310bbd PM	82	void (*idle)(void) = pm_idle;
	83
	84	if (!idle)
	85	idle = default_idle;
	86
57be2b48	87	tick_nohz_stop_sched_tick();
a3310bbd PM	88	while (!need_resched())
a3310bbd PM	89	idle();
57be2b48	90	tick_nohz_restart_sched_tick();
1da177e4	91
5bfb5d69	92	preempt_enable_no_resched();
1da177e4	93	schedule();
5bfb5d69	94	preempt_disable();
5f8c9908	95	check_pgt_cache();
1da177e4 LT	96	}
	97	}
	98
1da177e4 LT	99	void machine_restart(char * __unused)
	100	{
	101	/* SR.BL=1 and invoke address error to let CPU reset (manual reset) */
	102	asm volatile("ldc %0, sr\n\t"
	103	"mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001));
	104	}
	105
1da177e4 LT	106	void machine_halt(void)
1da177e4 LT	107	{
a3310bbd	108	local_irq_disable();
1da177e4	109
1da177e4 LT	110	while (1)
	111	cpu_sleep();
	112	}
	113
1da177e4 LT	114	void machine_power_off(void)
1da177e4 LT	115	{
a3310bbd PM	116	if (pm_power_off)
a3310bbd PM	117	pm_power_off();
1da177e4 LT	118	}
1da177e4 LT	119
1da177e4 LT	120	void show_regs(struct pt_regs * regs)
	121	{
	122	printk("\n");
	123	printk("Pid : %d, Comm: %20s\n", current->pid, current->comm);
6b002230	124	print_symbol("PC is at %s\n", instruction_pointer(regs));
1da177e4 LT	125	printk("PC : %08lx SP : %08lx SR : %08lx ",
	126	regs->pc, regs->regs[15], regs->sr);
	127	#ifdef CONFIG_MMU
	128	printk("TEA : %08x ", ctrl_inl(MMU_TEA));
	129	#else
	130	printk(" ");
	131	#endif
	132	printk("%s\n", print_tainted());
	133
	134	printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
	135	regs->regs[0],regs->regs[1],
	136	regs->regs[2],regs->regs[3]);
	137	printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
	138	regs->regs[4],regs->regs[5],
	139	regs->regs[6],regs->regs[7]);
	140	printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
	141	regs->regs[8],regs->regs[9],
	142	regs->regs[10],regs->regs[11]);
	143	printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
	144	regs->regs[12],regs->regs[13],
	145	regs->regs[14]);
	146	printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
	147	regs->mach, regs->macl, regs->gbr, regs->pr);
	148
6b002230	149	show_trace(NULL, (unsigned long *)regs->regs[15], regs);
1da177e4 LT	150	}
	151
	152	/*
	153	* Create a kernel thread
	154	*/
	155
	156	/*
	157	* This is the mechanism for creating a new kernel thread.
	158	*
	159	*/
	160	extern void kernel_thread_helper(void);
	161	__asm__(".align 5\n"
	162	"kernel_thread_helper:\n\t"
	163	"jsr @r5\n\t"
	164	" nop\n\t"
	165	"mov.l 1f, r1\n\t"
	166	"jsr @r1\n\t"
	167	" mov r0, r4\n\t"
	168	".align 2\n\t"
	169	"1:.long do_exit");
	170
aec5e0e1	171	/* Don't use this in BL=1(cli). Or else, CPU resets! */
1da177e4	172	int kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
aec5e0e1	173	{
1da177e4 LT	174	struct pt_regs regs;
	175
	176	memset(&regs, 0, sizeof(regs));
aec5e0e1 PM	177	regs.regs[4] = (unsigned long)arg;
aec5e0e1 PM	178	regs.regs[5] = (unsigned long)fn;
1da177e4	179
aec5e0e1	180	regs.pc = (unsigned long)kernel_thread_helper;
1da177e4 LT	181	regs.sr = (1 << 30);
	182
	183	/* Ok, create the new process.. */
aec5e0e1 PM	184	return do_fork(flags \| CLONE_VM \| CLONE_UNTRACED, 0,
aec5e0e1 PM	185	&regs, 0, NULL, NULL);
1da177e4 LT	186	}
	187
	188	/*
	189	* Free current thread data structures etc..
	190	*/
	191	void exit_thread(void)
	192	{
	193	if (current->thread.ubc_pc) {
	194	current->thread.ubc_pc = 0;
	195	ubc_usercnt -= 1;
	196	}
	197	}
	198
	199	void flush_thread(void)
	200	{
	201	#if defined(CONFIG_SH_FPU)
	202	struct task_struct *tsk = current;
1da177e4	203	/* Forget lazy FPU state */
3cf0f4ec	204	clear_fpu(tsk, task_pt_regs(tsk));
1da177e4 LT	205	clear_used_math();
	206	#endif
	207	}
	208
	209	void release_thread(struct task_struct *dead_task)
	210	{
	211	/* do nothing */
	212	}
	213
	214	/* Fill in the fpu structure for a core dump.. */
	215	int dump_fpu(struct pt_regs regs, elf_fpregset_t fpu)
	216	{
	217	int fpvalid = 0;
	218
	219	#if defined(CONFIG_SH_FPU)
	220	struct task_struct *tsk = current;
	221
	222	fpvalid = !!tsk_used_math(tsk);
	223	if (fpvalid) {
	224	unlazy_fpu(tsk, regs);
	225	memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	226	}
	227	#endif
	228
	229	return fpvalid;
	230	}
	231
aec5e0e1	232	/*
1da177e4 LT	233	* Capture the user space registers if the task is not running (in user space)
	234	*/
	235	int dump_task_regs(struct task_struct tsk, elf_gregset_t regs)
	236	{
	237	struct pt_regs ptregs;
aec5e0e1	238
3cf0f4ec	239	ptregs = *task_pt_regs(tsk);
1da177e4 LT	240	elf_core_copy_regs(regs, &ptregs);
	241
	242	return 1;
	243	}
	244
aec5e0e1	245	int dump_task_fpu(struct task_struct tsk, elf_fpregset_t fpu)
1da177e4 LT	246	{
	247	int fpvalid = 0;
	248
	249	#if defined(CONFIG_SH_FPU)
	250	fpvalid = !!tsk_used_math(tsk);
	251	if (fpvalid) {
3cf0f4ec	252	unlazy_fpu(tsk, task_pt_regs(tsk));
1da177e4 LT	253	memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
	254	}
	255	#endif
	256
	257	return fpvalid;
	258	}
	259
	260	asmlinkage void ret_from_fork(void);
	261
	262	int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
	263	unsigned long unused,
	264	struct task_struct p, struct pt_regs regs)
	265	{
2991be72	266	struct thread_info *ti = task_thread_info(p);
1da177e4 LT	267	struct pt_regs *childregs;
	268	#if defined(CONFIG_SH_FPU)
	269	struct task_struct *tsk = current;
	270
	271	unlazy_fpu(tsk, regs);
	272	p->thread.fpu = tsk->thread.fpu;
	273	copy_to_stopped_child_used_math(p);
	274	#endif
	275
3cf0f4ec	276	childregs = task_pt_regs(p);
1da177e4 LT	277	childregs = regs;
	278
	279	if (user_mode(regs)) {
	280	childregs->regs[15] = usp;
2991be72	281	ti->addr_limit = USER_DS;
1da177e4	282	} else {
e6bcf562	283	childregs->regs[15] = (unsigned long)childregs;
2991be72	284	ti->addr_limit = KERNEL_DS;
1da177e4	285	}
aec5e0e1	286
e6bcf562	287	if (clone_flags & CLONE_SETTLS)
1da177e4	288	childregs->gbr = childregs->regs[0];
aec5e0e1	289
1da177e4 LT	290	childregs->regs[0] = 0; /* Set return value for child */
	291
	292	p->thread.sp = (unsigned long) childregs;
	293	p->thread.pc = (unsigned long) ret_from_fork;
	294
	295	p->thread.ubc_pc = 0;
	296
	297	return 0;
	298	}
	299
1da177e4	300	/* Tracing by user break controller. */
aec5e0e1	301	static void ubc_set_tracing(int asid, unsigned long pc)
1da177e4	302	{
8ae91b9a RS	303	#if defined(CONFIG_CPU_SH4A)
	304	unsigned long val;
	305
	306	val = (UBC_CBR_ID_INST \| UBC_CBR_RW_READ \| UBC_CBR_CE);
	307	val \|= (UBC_CBR_AIE \| UBC_CBR_AIV_SET(asid));
	308
	309	ctrl_outl(val, UBC_CBR0);
	310	ctrl_outl(pc, UBC_CAR0);
	311	ctrl_outl(0x0, UBC_CAMR0);
	312	ctrl_outl(0x0, UBC_CBCR);
	313
	314	val = (UBC_CRR_RES \| UBC_CRR_PCB \| UBC_CRR_BIE);
	315	ctrl_outl(val, UBC_CRR0);
	316
aec5e0e1	317	/* Read UBC register that we wrote last, for checking update */
8ae91b9a RS	318	val = ctrl_inl(UBC_CRR0);
	319
	320	#else /* CONFIG_CPU_SH4A */
1da177e4 LT	321	ctrl_outl(pc, UBC_BARA);
1da177e4 LT	322
a2d1a5fa	323	#ifdef CONFIG_MMU
357d5946	324	ctrl_outb(asid, UBC_BASRA);
a2d1a5fa	325	#endif
1da177e4 LT	326
	327	ctrl_outl(0, UBC_BAMRA);
	328
11c19656	329	if (current_cpu_data.type == CPU_SH7729 \|\|
3a2e117e PM	330	current_cpu_data.type == CPU_SH7710 \|\|
3a2e117e PM	331	current_cpu_data.type == CPU_SH7712) {
1da177e4 LT	332	ctrl_outw(BBR_INST \| BBR_READ \| BBR_CPU, UBC_BBRA);
	333	ctrl_outl(BRCR_PCBA \| BRCR_PCTE, UBC_BRCR);
	334	} else {
	335	ctrl_outw(BBR_INST \| BBR_READ, UBC_BBRA);
	336	ctrl_outw(BRCR_PCBA, UBC_BRCR);
	337	}
8ae91b9a	338	#endif /* CONFIG_CPU_SH4A */
1da177e4 LT	339	}
	340
	341	/*
	342	* switch_to(x,y) should switch tasks from x to y.
	343	*
	344	*/
aec5e0e1 PM	345	struct task_struct __switch_to(struct task_struct prev,
aec5e0e1 PM	346	struct task_struct *next)
1da177e4 LT	347	{
1da177e4 LT	348	#if defined(CONFIG_SH_FPU)
3cf0f4ec	349	unlazy_fpu(prev, task_pt_regs(prev));
1da177e4 LT	350	#endif
	351
	352	#ifdef CONFIG_PREEMPT
	353	{
	354	unsigned long flags;
	355	struct pt_regs *regs;
	356
	357	local_irq_save(flags);
3cf0f4ec	358	regs = task_pt_regs(prev);
1da177e4 LT	359	if (user_mode(regs) && regs->regs[15] >= 0xc0000000) {
	360	int offset = (int)regs->regs[15];
	361
	362	/* Reset stack pointer: clear critical region mark */
	363	regs->regs[15] = regs->regs[1];
	364	if (regs->pc < regs->regs[0])
	365	/* Go to rewind point */
	366	regs->pc = regs->regs[0] + offset;
	367	}
	368	local_irq_restore(flags);
	369	}
	370	#endif
	371
a2d1a5fa	372	#ifdef CONFIG_MMU
1da177e4 LT	373	/*
1da177e4 LT	374	* Restore the kernel mode register
aec5e0e1	375	* k7 (r7_bank1)
1da177e4 LT	376	*/
	377	asm volatile("ldc %0, r7_bank"
	378	: /* no output */
cafcfcaa	379	: "r" (task_thread_info(next)));
a2d1a5fa	380	#endif
1da177e4	381
1da177e4 LT	382	/* If no tasks are using the UBC, we're done */
	383	if (ubc_usercnt == 0)
	384	/* If no tasks are using the UBC, we're done */;
	385	else if (next->thread.ubc_pc && next->mm) {
a2d1a5fa YS	386	int asid = 0;
a2d1a5fa YS	387	#ifdef CONFIG_MMU
aec5e0e1	388	asid \|= cpu_asid(smp_processor_id(), next->mm);
a2d1a5fa YS	389	#endif
a2d1a5fa YS	390	ubc_set_tracing(asid, next->thread.ubc_pc);
1da177e4	391	} else {
8ae91b9a RS	392	#if defined(CONFIG_CPU_SH4A)
	393	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	394	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
	395	#else
1da177e4 LT	396	ctrl_outw(0, UBC_BBRA);
1da177e4 LT	397	ctrl_outw(0, UBC_BBRB);
8ae91b9a	398	#endif
1da177e4	399	}
1da177e4 LT	400
	401	return prev;
	402	}
	403
	404	asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
	405	unsigned long r6, unsigned long r7,
f0bc814c	406	struct pt_regs __regs)
1da177e4 LT	407	{
1da177e4 LT	408	#ifdef CONFIG_MMU
882c12c4	409	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c	410	return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
1da177e4 LT	411	#else
	412	/* fork almost works, enough to trick you into looking elsewhere :-( */
	413	return -EINVAL;
	414	#endif
	415	}
	416
	417	asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
	418	unsigned long parent_tidptr,
	419	unsigned long child_tidptr,
f0bc814c	420	struct pt_regs __regs)
1da177e4	421	{
f0bc814c	422	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4	423	if (!newsp)
f0bc814c SM	424	newsp = regs->regs[15];
f0bc814c SM	425	return do_fork(clone_flags, newsp, regs, 0,
aec5e0e1 PM	426	(int __user *)parent_tidptr,
aec5e0e1 PM	427	(int __user *)child_tidptr);
1da177e4 LT	428	}
	429
	430	/*
	431	* This is trivial, and on the face of it looks like it
	432	* could equally well be done in user mode.
	433	*
	434	* Not so, for quite unobvious reasons - register pressure.
	435	* In user mode vfork() cannot have a stack frame, and if
	436	* done by calling the "clone()" system call directly, you
	437	* do not have enough call-clobbered registers to hold all
	438	* the information you need.
	439	*/
	440	asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
	441	unsigned long r6, unsigned long r7,
f0bc814c	442	struct pt_regs __regs)
1da177e4	443	{
f0bc814c SM	444	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	445	return do_fork(CLONE_VFORK \| CLONE_VM \| SIGCHLD, regs->regs[15], regs,
1da177e4 LT	446	0, NULL, NULL);
	447	}
	448
	449	/*
	450	* sys_execve() executes a new program.
	451	*/
e08f457c PM	452	asmlinkage int sys_execve(char __user ufilename, char __user __user *uargv,
e08f457c PM	453	char __user * __user *uenvp, unsigned long r7,
f0bc814c	454	struct pt_regs __regs)
1da177e4	455	{
f0bc814c	456	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
1da177e4 LT	457	int error;
	458	char *filename;
	459
e08f457c	460	filename = getname(ufilename);
1da177e4 LT	461	error = PTR_ERR(filename);
	462	if (IS_ERR(filename))
	463	goto out;
	464
e08f457c	465	error = do_execve(filename, uargv, uenvp, regs);
1da177e4 LT	466	if (error == 0) {
	467	task_lock(current);
	468	current->ptrace &= ~PT_DTRACE;
	469	task_unlock(current);
	470	}
	471	putname(filename);
	472	out:
	473	return error;
	474	}
	475
	476	unsigned long get_wchan(struct task_struct *p)
	477	{
1da177e4 LT	478	unsigned long pc;
	479
	480	if (!p \|\| p == current \|\| p->state == TASK_RUNNING)
	481	return 0;
	482
	483	/*
	484	* The same comment as on the Alpha applies here, too ...
	485	*/
	486	pc = thread_saved_pc(p);
c64ac9f0 DM	487
c64ac9f0 DM	488	#ifdef CONFIG_FRAME_POINTER
1da177e4	489	if (in_sched_functions(pc)) {
c64ac9f0	490	unsigned long schedule_frame = (unsigned long)p->thread.sp;
b652c23c	491	return ((unsigned long *)schedule_frame)[21];
1da177e4	492	}
c64ac9f0	493	#endif
b652c23c	494
1da177e4 LT	495	return pc;
	496	}
	497
f0bc814c	498	asmlinkage void break_point_trap(void)
1da177e4 LT	499	{
1da177e4 LT	500	/* Clear tracing. */
8ae91b9a RS	501	#if defined(CONFIG_CPU_SH4A)
	502	ctrl_outl(UBC_CBR_INIT, UBC_CBR0);
	503	ctrl_outl(UBC_CRR_INIT, UBC_CRR0);
	504	#else
1da177e4 LT	505	ctrl_outw(0, UBC_BBRA);
1da177e4 LT	506	ctrl_outw(0, UBC_BBRB);
8ae91b9a	507	#endif
1da177e4 LT	508	current->thread.ubc_pc = 0;
	509	ubc_usercnt -= 1;
	510
	511	force_sig(SIGTRAP, current);
	512	}
	513
f413d0d9 PM	514	/*
	515	* Generic trap handler.
	516	*/
	517	asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5,
	518	unsigned long r6, unsigned long r7,
	519	struct pt_regs __regs)
	520	{
	521	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
	522
	523	/* Rewind */
53f983a9	524	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
f413d0d9	525
b118ca57	526	if (notify_die(DIE_TRAP, "debug trap", regs, 0, regs->tra & 0xff,
3a2e117e PM	527	SIGTRAP) == NOTIFY_STOP)
	528	return;
	529
f413d0d9 PM	530	force_sig(SIGTRAP, current);
	531	}
	532
	533	/*
	534	* Special handler for BUG() traps.
	535	*/
	536	asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5,
	537	unsigned long r6, unsigned long r7,
	538	struct pt_regs __regs)
1da177e4	539	{
f0bc814c SM	540	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
f0bc814c SM	541
dc34d312	542	/* Rewind */
53f983a9	543	regs->pc -= instruction_size(ctrl_inw(regs->pc - 4));
dc34d312	544
b118ca57	545	if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff,
3a2e117e PM	546	SIGTRAP) == NOTIFY_STOP)
	547	return;
	548
dc34d312 PM	549	#ifdef CONFIG_BUG
	550	if (__kernel_text_address(instruction_pointer(regs))) {
	551	u16 insn = (u16 )instruction_pointer(regs);
	552	if (insn == TRAPA_BUG_OPCODE)
	553	handle_BUG(regs);
	554	}
	555	#endif
	556
1da177e4 LT	557	force_sig(SIGTRAP, current);
1da177e4 LT	558	}