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

/*  linux/arch/sparc/kernel/process.c
 *
 *  Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
 *  Copyright (C) 1996 Eddie C. Dost   (ecd@skynet.be)
 */

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

#include <stdarg.h>

#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/slab.h>

#include <asm/auxio.h>
#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/delay.h>
#include <asm/processor.h>
#include <asm/psr.h>
#include <asm/elf.h>
#include <asm/prom.h>
#include <asm/unistd.h>
#include <asm/setup.h>

/* 
 * Power management idle function 
 * Set in pm platform drivers (apc.c and pmc.c)
 */
void (*sparc_idle)(void);

/* 
 * Power-off handler instantiation for pm.h compliance
 * This is done via auxio, but could be used as a fallback
 * handler when auxio is not present-- unused for now...
 */
void (*pm_power_off)(void) = machine_power_off;
EXPORT_SYMBOL(pm_power_off);

/*
 * sysctl - toggle power-off restriction for serial console 
 * systems in machine_power_off()
 */
int scons_pwroff = 1;

extern void fpsave(unsigned long *, unsigned long *, void *, unsigned long *);

struct task_struct *last_task_used_math = NULL;
struct thread_info *current_set[NR_CPUS];

/* Idle loop support. */
void arch_cpu_idle(void)
{
	if (sparc_idle)
		(*sparc_idle)();
	local_irq_enable();
}

/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
void machine_halt(void)
{
	local_irq_enable();
	mdelay(8);
	local_irq_disable();
	prom_halt();
	panic("Halt failed!");
}

void machine_restart(char * cmd)
{
	char *p;
	
	local_irq_enable();
	mdelay(8);
	local_irq_disable();

	p = strchr (reboot_command, '\n');
	if (p) *p = 0;
	if (cmd)
		prom_reboot(cmd);
	if (*reboot_command)
		prom_reboot(reboot_command);
	prom_feval ("reset");
	panic("Reboot failed!");
}

void machine_power_off(void)
{
	if (auxio_power_register &&
	    (strcmp(of_console_device->type, "serial") || scons_pwroff))
		*auxio_power_register |= AUXIO_POWER_OFF;
	machine_halt();
}

void show_regs(struct pt_regs *r)
{
	struct reg_window32 *rw = (struct reg_window32 *) r->u_regs[14];

	show_regs_print_info(KERN_DEFAULT);

        printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx    %s\n",
	       r->psr, r->pc, r->npc, r->y, print_tainted());
	printk("PC: <%pS>\n", (void *) r->pc);
	printk("%%G: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",
	       r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
	       r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
	printk("%%O: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",
	       r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
	       r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
	printk("RPC: <%pS>\n", (void *) r->u_regs[15]);

	printk("%%L: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",
	       rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
	       rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
	printk("%%I: %08lx %08lx  %08lx %08lx  %08lx %08lx  %08lx %08lx\n",
	       rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
	       rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
}

/*
 * The show_stack is an external API which we do not use ourselves.
 * The oops is printed in die_if_kernel.
 */
void show_stack(struct task_struct *tsk, unsigned long *_ksp)
{
	unsigned long pc, fp;
	unsigned long task_base;
	struct reg_window32 *rw;
	int count = 0;

	if (!tsk)
		tsk = current;

	if (tsk == current && !_ksp)
		__asm__ __volatile__("mov	%%fp, %0" : "=r" (_ksp));

	task_base = (unsigned long) task_stack_page(tsk);
	fp = (unsigned long) _ksp;
	do {
		/* Bogus frame pointer? */
		if (fp < (task_base + sizeof(struct thread_info)) ||
		    fp >= (task_base + (PAGE_SIZE << 1)))
			break;
		rw = (struct reg_window32 *) fp;
		pc = rw->ins[7];
		printk("[%08lx : ", pc);
		printk("%pS ] ", (void *) pc);
		fp = rw->ins[6];
	} while (++count < 16);
	printk("\n");
}

/*
 * Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
 */
unsigned long thread_saved_pc(struct task_struct *tsk)
{
	return task_thread_info(tsk)->kpc;
}

/*
 * Free current thread data structures etc..
 */
void exit_thread(void)
{
#ifndef CONFIG_SMP
	if(last_task_used_math == current) {
#else
	if (test_thread_flag(TIF_USEDFPU)) {
#endif
		/* Keep process from leaving FPU in a bogon state. */
		put_psr(get_psr() | PSR_EF);
		fpsave(&current->thread.float_regs[0], &current->thread.fsr,
		       &current->thread.fpqueue[0], &current->thread.fpqdepth);
#ifndef CONFIG_SMP
		last_task_used_math = NULL;
#else
		clear_thread_flag(TIF_USEDFPU);
#endif
	}
}

void flush_thread(void)
{
	current_thread_info()->w_saved = 0;

#ifndef CONFIG_SMP
	if(last_task_used_math == current) {
#else
	if (test_thread_flag(TIF_USEDFPU)) {
#endif
		/* Clean the fpu. */
		put_psr(get_psr() | PSR_EF);
		fpsave(&current->thread.float_regs[0], &current->thread.fsr,
		       &current->thread.fpqueue[0], &current->thread.fpqdepth);
#ifndef CONFIG_SMP
		last_task_used_math = NULL;
#else
		clear_thread_flag(TIF_USEDFPU);
#endif
	}

	/* This task is no longer a kernel thread. */
	if (current->thread.flags & SPARC_FLAG_KTHREAD) {
		current->thread.flags &= ~SPARC_FLAG_KTHREAD;

		/* We must fixup kregs as well. */
		/* XXX This was not fixed for ti for a while, worked. Unused? */
		current->thread.kregs = (struct pt_regs *)
		    (task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
	}
}

static inline struct sparc_stackf __user *
clone_stackframe(struct sparc_stackf __user *dst,
		 struct sparc_stackf __user *src)
{
	unsigned long size, fp;
	struct sparc_stackf *tmp;
	struct sparc_stackf __user *sp;

	if (get_user(tmp, &src->fp))
		return NULL;

	fp = (unsigned long) tmp;
	size = (fp - ((unsigned long) src));
	fp = (unsigned long) dst;
	sp = (struct sparc_stackf __user *)(fp - size); 

	/* do_fork() grabs the parent semaphore, we must release it
	 * temporarily so we can build the child clone stack frame
	 * without deadlocking.
	 */
	if (__copy_user(sp, src, size))
		sp = NULL;
	else if (put_user(fp, &sp->fp))
		sp = NULL;

	return sp;
}

asmlinkage int sparc_do_fork(unsigned long clone_flags,
                             unsigned long stack_start,
                             struct pt_regs *regs,
                             unsigned long stack_size)
{
	unsigned long parent_tid_ptr, child_tid_ptr;
	unsigned long orig_i1 = regs->u_regs[UREG_I1];
	long ret;

	parent_tid_ptr = regs->u_regs[UREG_I2];
	child_tid_ptr = regs->u_regs[UREG_I4];

	ret = do_fork(clone_flags, stack_start, stack_size,
		      (int __user *) parent_tid_ptr,
		      (int __user *) child_tid_ptr);

	/* If we get an error and potentially restart the system
	 * call, we're screwed because copy_thread() clobbered
	 * the parent's %o1.  So detect that case and restore it
	 * here.
	 */
	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
		regs->u_regs[UREG_I1] = orig_i1;

	return ret;
}

/* Copy a Sparc thread.  The fork() return value conventions
 * under SunOS are nothing short of bletcherous:
 * Parent -->  %o0 == childs  pid, %o1 == 0
 * Child  -->  %o0 == parents pid, %o1 == 1
 *
 * NOTE: We have a separate fork kpsr/kwim because
 *       the parent could change these values between
 *       sys_fork invocation and when we reach here
 *       if the parent should sleep while trying to
 *       allocate the task_struct and kernel stack in
 *       do_fork().
 * XXX See comment above sys_vfork in sparc64. todo.
 */
extern void ret_from_fork(void);
extern void ret_from_kernel_thread(void);

int copy_thread(unsigned long clone_flags, unsigned long sp,
		unsigned long arg, struct task_struct *p)
{
	struct thread_info *ti = task_thread_info(p);
	struct pt_regs *childregs, *regs = current_pt_regs();
	char *new_stack;

#ifndef CONFIG_SMP
	if(last_task_used_math == current) {
#else
	if (test_thread_flag(TIF_USEDFPU)) {
#endif
		put_psr(get_psr() | PSR_EF);
		fpsave(&p->thread.float_regs[0], &p->thread.fsr,
		       &p->thread.fpqueue[0], &p->thread.fpqdepth);
	}

	/*
	 *  p->thread_info         new_stack   childregs stack bottom
	 *  !                      !           !             !
	 *  V                      V (stk.fr.) V  (pt_regs)  V
	 *  +----- - - - - - ------+===========+=============+
	 */
	new_stack = task_stack_page(p) + THREAD_SIZE;
	new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
	childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);

	/*
	 * A new process must start with interrupts closed in 2.5,
	 * because this is how Mingo's scheduler works (see schedule_tail
	 * and finish_arch_switch). If we do not do it, a timer interrupt hits
	 * before we unlock, attempts to re-take the rq->lock, and then we die.
	 * Thus, kpsr|=PSR_PIL.
	 */
	ti->ksp = (unsigned long) new_stack;
	p->thread.kregs = childregs;

	if (unlikely(p->flags & PF_KTHREAD)) {
		extern int nwindows;
		unsigned long psr;
		memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
		p->thread.flags |= SPARC_FLAG_KTHREAD;
		p->thread.current_ds = KERNEL_DS;
		ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
		childregs->u_regs[UREG_G1] = sp; /* function */
		childregs->u_regs[UREG_G2] = arg;
		psr = childregs->psr = get_psr();
		ti->kpsr = psr | PSR_PIL;
		ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
		return 0;
	}
	memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
	childregs->u_regs[UREG_FP] = sp;
	p->thread.flags &= ~SPARC_FLAG_KTHREAD;
	p->thread.current_ds = USER_DS;
	ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
	ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
	ti->kwim = current->thread.fork_kwim;

	if (sp != regs->u_regs[UREG_FP]) {
		struct sparc_stackf __user *childstack;
		struct sparc_stackf __user *parentstack;

		/*
		 * This is a clone() call with supplied user stack.
		 * Set some valid stack frames to give to the child.
		 */
		childstack = (struct sparc_stackf __user *)
			(sp & ~0xfUL);
		parentstack = (struct sparc_stackf __user *)
			regs->u_regs[UREG_FP];

#if 0
		printk("clone: parent stack:\n");
		show_stackframe(parentstack);
#endif

		childstack = clone_stackframe(childstack, parentstack);
		if (!childstack)
			return -EFAULT;

#if 0
		printk("clone: child stack:\n");
		show_stackframe(childstack);
#endif

		childregs->u_regs[UREG_FP] = (unsigned long)childstack;
	}

#ifdef CONFIG_SMP
	/* FPU must be disabled on SMP. */
	childregs->psr &= ~PSR_EF;
	clear_tsk_thread_flag(p, TIF_USEDFPU);
#endif

	/* Set the return value for the child. */
	childregs->u_regs[UREG_I0] = current->pid;
	childregs->u_regs[UREG_I1] = 1;

	/* Set the return value for the parent. */
	regs->u_regs[UREG_I1] = 0;

	if (clone_flags & CLONE_SETTLS)
		childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];

	return 0;
}

/*
 * fill in the fpu structure for a core dump.
 */
int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
{
	if (used_math()) {
		memset(fpregs, 0, sizeof(*fpregs));
		fpregs->pr_q_entrysize = 8;
		return 1;
	}
#ifdef CONFIG_SMP
	if (test_thread_flag(TIF_USEDFPU)) {
		put_psr(get_psr() | PSR_EF);
		fpsave(&current->thread.float_regs[0], &current->thread.fsr,
		       &current->thread.fpqueue[0], &current->thread.fpqdepth);
		if (regs != NULL) {
			regs->psr &= ~(PSR_EF);
			clear_thread_flag(TIF_USEDFPU);
		}
	}
#else
	if (current == last_task_used_math) {
		put_psr(get_psr() | PSR_EF);
		fpsave(&current->thread.float_regs[0], &current->thread.fsr,
		       &current->thread.fpqueue[0], &current->thread.fpqdepth);
		if (regs != NULL) {
			regs->psr &= ~(PSR_EF);
			last_task_used_math = NULL;
		}
	}
#endif
	memcpy(&fpregs->pr_fr.pr_regs[0],
	       &current->thread.float_regs[0],
	       (sizeof(unsigned long) * 32));
	fpregs->pr_fsr = current->thread.fsr;
	fpregs->pr_qcnt = current->thread.fpqdepth;
	fpregs->pr_q_entrysize = 8;
	fpregs->pr_en = 1;
	if(fpregs->pr_qcnt != 0) {
		memcpy(&fpregs->pr_q[0],
		       &current->thread.fpqueue[0],
		       sizeof(struct fpq) * fpregs->pr_qcnt);
	}
	/* Zero out the rest. */
	memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
	       sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
	return 1;
}

unsigned long get_wchan(struct task_struct *task)
{
	unsigned long pc, fp, bias = 0;
	unsigned long task_base = (unsigned long) task;
        unsigned long ret = 0;
	struct reg_window32 *rw;
	int count = 0;

	if (!task || task == current ||
            task->state == TASK_RUNNING)
		goto out;

	fp = task_thread_info(task)->ksp + bias;
	do {
		/* Bogus frame pointer? */
		if (fp < (task_base + sizeof(struct thread_info)) ||
		    fp >= (task_base + (2 * PAGE_SIZE)))
			break;
		rw = (struct reg_window32 *) fp;
		pc = rw->ins[7];
		if (!in_sched_functions(pc)) {
			ret = pc;
			goto out;
		}
		fp = rw->ins[6] + bias;
	} while (++count < 16);

out:
	return ret;
}
Commit	Line	Data
64d329ee	1	/* linux/arch/sparc/kernel/process.c
1da177e4	2	*
4fe3ebec	3	* Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
1da177e4 LT	4	* Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
	5	*/
	6
	7	/*
	8	* This file handles the architecture-dependent parts of process handling..
	9	*/
	10
	11	#include <stdarg.h>
	12
	13	#include <linux/errno.h>
	14	#include <linux/module.h>
	15	#include <linux/sched.h>
	16	#include <linux/kernel.h>
1da177e4 LT	17	#include <linux/mm.h>
	18	#include <linux/stddef.h>
	19	#include <linux/ptrace.h>
1da177e4	20	#include <linux/user.h>
1da177e4	21	#include <linux/smp.h>
1da177e4 LT	22	#include <linux/reboot.h>
	23	#include <linux/delay.h>
	24	#include <linux/pm.h>
5a0e3ad6	25	#include <linux/slab.h>
1da177e4 LT	26
	27	#include <asm/auxio.h>
	28	#include <asm/oplib.h>
	29	#include <asm/uaccess.h>
1da177e4 LT	30	#include <asm/page.h>
	31	#include <asm/pgalloc.h>
	32	#include <asm/pgtable.h>
	33	#include <asm/delay.h>
	34	#include <asm/processor.h>
	35	#include <asm/psr.h>
	36	#include <asm/elf.h>
c73fcc84	37	#include <asm/prom.h>
1da177e4	38	#include <asm/unistd.h>
d550bbd4	39	#include <asm/setup.h>
1da177e4 LT	40
	41	/*
	42	* Power management idle function
	43	* Set in pm platform drivers (apc.c and pmc.c)
	44	*/
d472ba84	45	void (*sparc_idle)(void);
1da177e4 LT	46
	47	/*
	48	* Power-off handler instantiation for pm.h compliance
	49	* This is done via auxio, but could be used as a fallback
	50	* handler when auxio is not present-- unused for now...
	51	*/
304cd3ef	52	void (*pm_power_off)(void) = machine_power_off;
89eb1693	53	EXPORT_SYMBOL(pm_power_off);
1da177e4 LT	54
	55	/*
	56	* sysctl - toggle power-off restriction for serial console
	57	* systems in machine_power_off()
	58	*/
	59	int scons_pwroff = 1;
	60
	61	extern void fpsave(unsigned long , unsigned long , void , unsigned long );
	62
	63	struct task_struct *last_task_used_math = NULL;
	64	struct thread_info *current_set[NR_CPUS];
	65
87fa05ae SR	66	/* Idle loop support. */
87fa05ae SR	67	void arch_cpu_idle(void)
1da177e4	68	{
87fa05ae SR	69	if (sparc_idle)
	70	(*sparc_idle)();
	71	local_irq_enable();
1da177e4 LT	72	}
1da177e4 LT	73
1da177e4 LT	74	/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
	75	void machine_halt(void)
	76	{
	77	local_irq_enable();
	78	mdelay(8);
	79	local_irq_disable();
1da177e4 LT	80	prom_halt();
	81	panic("Halt failed!");
	82	}
	83
1da177e4 LT	84	void machine_restart(char * cmd)
	85	{
	86	char *p;
	87
	88	local_irq_enable();
	89	mdelay(8);
	90	local_irq_disable();
	91
	92	p = strchr (reboot_command, '\n');
	93	if (p) *p = 0;
1da177e4 LT	94	if (cmd)
	95	prom_reboot(cmd);
	96	if (*reboot_command)
	97	prom_reboot(reboot_command);
	98	prom_feval ("reset");
	99	panic("Reboot failed!");
	100	}
	101
1da177e4 LT	102	void machine_power_off(void)
1da177e4 LT	103	{
c73fcc84 DM	104	if (auxio_power_register &&
c73fcc84 DM	105	(strcmp(of_console_device->type, "serial") \|\| scons_pwroff))
1da177e4	106	*auxio_power_register \|= AUXIO_POWER_OFF;
1da177e4 LT	107	machine_halt();
	108	}
	109
1da177e4 LT	110	void show_regs(struct pt_regs *r)
1da177e4 LT	111	{
4d7b92ad	112	struct reg_window32 rw = (struct reg_window32 ) r->u_regs[14];
1da177e4	113
a43cb95d TH	114	show_regs_print_info(KERN_DEFAULT);
a43cb95d TH	115
1da177e4 LT	116	printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
1da177e4 LT	117	r->psr, r->pc, r->npc, r->y, print_tainted());
4fe3ebec	118	printk("PC: <%pS>\n", (void *) r->pc);
1da177e4 LT	119	printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	120	r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
	121	r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
	122	printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	123	r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
	124	r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
4fe3ebec	125	printk("RPC: <%pS>\n", (void *) r->u_regs[15]);
1da177e4 LT	126
	127	printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	128	rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
	129	rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
	130	printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	131	rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
	132	rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
	133	}
	134
	135	/*
	136	* The show_stack is an external API which we do not use ourselves.
	137	* The oops is printed in die_if_kernel.
	138	*/
	139	void show_stack(struct task_struct tsk, unsigned long _ksp)
	140	{
	141	unsigned long pc, fp;
	142	unsigned long task_base;
4d7b92ad	143	struct reg_window32 *rw;
1da177e4 LT	144	int count = 0;
1da177e4 LT	145
89e3f23d TH	146	if (!tsk)
89e3f23d TH	147	tsk = current;
1da177e4	148
89e3f23d TH	149	if (tsk == current && !_ksp)
	150	__asm__ __volatile__("mov %%fp, %0" : "=r" (_ksp));
	151
	152	task_base = (unsigned long) task_stack_page(tsk);
1da177e4 LT	153	fp = (unsigned long) _ksp;
	154	do {
	155	/* Bogus frame pointer? */
	156	if (fp < (task_base + sizeof(struct thread_info)) \|\|
	157	fp >= (task_base + (PAGE_SIZE << 1)))
	158	break;
4d7b92ad	159	rw = (struct reg_window32 *) fp;
1da177e4 LT	160	pc = rw->ins[7];
1da177e4 LT	161	printk("[%08lx : ", pc);
4fe3ebec	162	printk("%pS ] ", (void *) pc);
1da177e4 LT	163	fp = rw->ins[6];
	164	} while (++count < 16);
	165	printk("\n");
	166	}
	167
	168	/*
	169	* Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
	170	*/
	171	unsigned long thread_saved_pc(struct task_struct *tsk)
	172	{
d562ef6a	173	return task_thread_info(tsk)->kpc;
1da177e4 LT	174	}
	175
	176	/*
	177	* Free current thread data structures etc..
	178	*/
	179	void exit_thread(void)
	180	{
	181	#ifndef CONFIG_SMP
	182	if(last_task_used_math == current) {
	183	#else
54f565ea	184	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	185	#endif
	186	/* Keep process from leaving FPU in a bogon state. */
	187	put_psr(get_psr() \| PSR_EF);
	188	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	189	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	190	#ifndef CONFIG_SMP
	191	last_task_used_math = NULL;
	192	#else
54f565ea	193	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	194	#endif
	195	}
	196	}
	197
	198	void flush_thread(void)
	199	{
	200	current_thread_info()->w_saved = 0;
	201
1da177e4 LT	202	#ifndef CONFIG_SMP
	203	if(last_task_used_math == current) {
	204	#else
54f565ea	205	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	206	#endif
	207	/* Clean the fpu. */
	208	put_psr(get_psr() \| PSR_EF);
	209	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	210	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	211	#ifndef CONFIG_SMP
	212	last_task_used_math = NULL;
	213	#else
54f565ea	214	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	215	#endif
	216	}
	217
ddd53bf1	218	/* This task is no longer a kernel thread. */
1da177e4 LT	219	if (current->thread.flags & SPARC_FLAG_KTHREAD) {
	220	current->thread.flags &= ~SPARC_FLAG_KTHREAD;
	221
	222	/* We must fixup kregs as well. */
	223	/* XXX This was not fixed for ti for a while, worked. Unused? */
	224	current->thread.kregs = (struct pt_regs *)
36483c6b	225	(task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
1da177e4 LT	226	}
	227	}
	228
64d329ee	229	static inline struct sparc_stackf __user *
1da177e4 LT	230	clone_stackframe(struct sparc_stackf __user *dst,
	231	struct sparc_stackf __user *src)
	232	{
	233	unsigned long size, fp;
	234	struct sparc_stackf *tmp;
	235	struct sparc_stackf __user *sp;
	236
	237	if (get_user(tmp, &src->fp))
	238	return NULL;
	239
	240	fp = (unsigned long) tmp;
	241	size = (fp - ((unsigned long) src));
	242	fp = (unsigned long) dst;
	243	sp = (struct sparc_stackf __user *)(fp - size);
	244
	245	/* do_fork() grabs the parent semaphore, we must release it
	246	* temporarily so we can build the child clone stack frame
	247	* without deadlocking.
	248	*/
	249	if (__copy_user(sp, src, size))
	250	sp = NULL;
	251	else if (put_user(fp, &sp->fp))
	252	sp = NULL;
	253
	254	return sp;
	255	}
	256
	257	asmlinkage int sparc_do_fork(unsigned long clone_flags,
	258	unsigned long stack_start,
	259	struct pt_regs *regs,
	260	unsigned long stack_size)
	261	{
	262	unsigned long parent_tid_ptr, child_tid_ptr;
1e38c126 DM	263	unsigned long orig_i1 = regs->u_regs[UREG_I1];
1e38c126 DM	264	long ret;
1da177e4 LT	265
	266	parent_tid_ptr = regs->u_regs[UREG_I2];
	267	child_tid_ptr = regs->u_regs[UREG_I4];
	268
e80d6661	269	ret = do_fork(clone_flags, stack_start, stack_size,
1e38c126 DM	270	(int __user *) parent_tid_ptr,
	271	(int __user *) child_tid_ptr);
	272
	273	/* If we get an error and potentially restart the system
	274	* call, we're screwed because copy_thread() clobbered
	275	* the parent's %o1. So detect that case and restore it
	276	* here.
	277	*/
	278	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
	279	regs->u_regs[UREG_I1] = orig_i1;
	280
	281	return ret;
1da177e4 LT	282	}
	283
	284	/* Copy a Sparc thread. The fork() return value conventions
	285	* under SunOS are nothing short of bletcherous:
	286	* Parent --> %o0 == childs pid, %o1 == 0
	287	* Child --> %o0 == parents pid, %o1 == 1
	288	*
	289	* NOTE: We have a separate fork kpsr/kwim because
	290	* the parent could change these values between
	291	* sys_fork invocation and when we reach here
	292	* if the parent should sleep while trying to
	293	* allocate the task_struct and kernel stack in
	294	* do_fork().
	295	* XXX See comment above sys_vfork in sparc64. todo.
	296	*/
	297	extern void ret_from_fork(void);
c78e0643	298	extern void ret_from_kernel_thread(void);
1da177e4	299
6f2c55b8	300	int copy_thread(unsigned long clone_flags, unsigned long sp,
afa86fc4	301	unsigned long arg, struct task_struct *p)
1da177e4	302	{
36483c6b	303	struct thread_info *ti = task_thread_info(p);
afa86fc4	304	struct pt_regs childregs, regs = current_pt_regs();
1da177e4 LT	305	char *new_stack;
	306
	307	#ifndef CONFIG_SMP
	308	if(last_task_used_math == current) {
	309	#else
54f565ea	310	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	311	#endif
	312	put_psr(get_psr() \| PSR_EF);
	313	fpsave(&p->thread.float_regs[0], &p->thread.fsr,
	314	&p->thread.fpqueue[0], &p->thread.fpqdepth);
1da177e4 LT	315	}
	316
	317	/*
c78e0643 AV	318	* p->thread_info new_stack childregs stack bottom
	319	* ! ! ! !
	320	* V V (stk.fr.) V (pt_regs) V
	321	* +----- - - - - - ------+===========+=============+
1da177e4	322	*/
36483c6b	323	new_stack = task_stack_page(p) + THREAD_SIZE;
1da177e4	324	new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
1da177e4 LT	325	childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
	326
	327	/*
	328	* A new process must start with interrupts closed in 2.5,
	329	* because this is how Mingo's scheduler works (see schedule_tail
	330	* and finish_arch_switch). If we do not do it, a timer interrupt hits
	331	* before we unlock, attempts to re-take the rq->lock, and then we die.
	332	* Thus, kpsr\|=PSR_PIL.
	333	*/
	334	ti->ksp = (unsigned long) new_stack;
c78e0643 AV	335	p->thread.kregs = childregs;
	336
	337	if (unlikely(p->flags & PF_KTHREAD)) {
	338	extern int nwindows;
	339	unsigned long psr;
	340	memset(new_stack, 0, STACKFRAME_SZ + TRACEREG_SZ);
	341	p->thread.flags \|= SPARC_FLAG_KTHREAD;
	342	p->thread.current_ds = KERNEL_DS;
	343	ti->kpc = (((unsigned long) ret_from_kernel_thread) - 0x8);
	344	childregs->u_regs[UREG_G1] = sp; /* function */
	345	childregs->u_regs[UREG_G2] = arg;
	346	psr = childregs->psr = get_psr();
	347	ti->kpsr = psr \| PSR_PIL;
	348	ti->kwim = 1 << (((psr & PSR_CWP) + 1) % nwindows);
	349	return 0;
	350	}
	351	memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
	352	childregs->u_regs[UREG_FP] = sp;
	353	p->thread.flags &= ~SPARC_FLAG_KTHREAD;
	354	p->thread.current_ds = USER_DS;
1da177e4 LT	355	ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
	356	ti->kpsr = current->thread.fork_kpsr \| PSR_PIL;
	357	ti->kwim = current->thread.fork_kwim;
	358
c78e0643 AV	359	if (sp != regs->u_regs[UREG_FP]) {
	360	struct sparc_stackf __user *childstack;
	361	struct sparc_stackf __user *parentstack;
1da177e4	362
c78e0643 AV	363	/*
	364	* This is a clone() call with supplied user stack.
	365	* Set some valid stack frames to give to the child.
	366	*/
	367	childstack = (struct sparc_stackf __user *)
	368	(sp & ~0xfUL);
	369	parentstack = (struct sparc_stackf __user *)
	370	regs->u_regs[UREG_FP];
1da177e4 LT	371
1da177e4 LT	372	#if 0
c78e0643 AV	373	printk("clone: parent stack:\n");
c78e0643 AV	374	show_stackframe(parentstack);
1da177e4 LT	375	#endif
1da177e4 LT	376
c78e0643 AV	377	childstack = clone_stackframe(childstack, parentstack);
	378	if (!childstack)
	379	return -EFAULT;
1da177e4 LT	380
1da177e4 LT	381	#if 0
c78e0643 AV	382	printk("clone: child stack:\n");
c78e0643 AV	383	show_stackframe(childstack);
1da177e4 LT	384	#endif
1da177e4 LT	385
c78e0643	386	childregs->u_regs[UREG_FP] = (unsigned long)childstack;
1da177e4 LT	387	}
	388
	389	#ifdef CONFIG_SMP
	390	/* FPU must be disabled on SMP. */
	391	childregs->psr &= ~PSR_EF;
427f23cb	392	clear_tsk_thread_flag(p, TIF_USEDFPU);
1da177e4 LT	393	#endif
	394
	395	/* Set the return value for the child. */
	396	childregs->u_regs[UREG_I0] = current->pid;
	397	childregs->u_regs[UREG_I1] = 1;
	398
	399	/* Set the return value for the parent. */
	400	regs->u_regs[UREG_I1] = 0;
	401
	402	if (clone_flags & CLONE_SETTLS)
	403	childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
	404
	405	return 0;
	406	}
	407
1da177e4 LT	408	/*
	409	* fill in the fpu structure for a core dump.
	410	*/
	411	int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
	412	{
	413	if (used_math()) {
	414	memset(fpregs, 0, sizeof(*fpregs));
	415	fpregs->pr_q_entrysize = 8;
	416	return 1;
	417	}
	418	#ifdef CONFIG_SMP
54f565ea	419	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	420	put_psr(get_psr() \| PSR_EF);
	421	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	422	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	423	if (regs != NULL) {
	424	regs->psr &= ~(PSR_EF);
54f565ea	425	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	426	}
	427	}
	428	#else
	429	if (current == last_task_used_math) {
	430	put_psr(get_psr() \| PSR_EF);
	431	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	432	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	433	if (regs != NULL) {
	434	regs->psr &= ~(PSR_EF);
	435	last_task_used_math = NULL;
	436	}
	437	}
	438	#endif
	439	memcpy(&fpregs->pr_fr.pr_regs[0],
	440	&current->thread.float_regs[0],
	441	(sizeof(unsigned long) * 32));
	442	fpregs->pr_fsr = current->thread.fsr;
	443	fpregs->pr_qcnt = current->thread.fpqdepth;
	444	fpregs->pr_q_entrysize = 8;
	445	fpregs->pr_en = 1;
	446	if(fpregs->pr_qcnt != 0) {
	447	memcpy(&fpregs->pr_q[0],
	448	&current->thread.fpqueue[0],
	449	sizeof(struct fpq) * fpregs->pr_qcnt);
	450	}
	451	/* Zero out the rest. */
	452	memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
	453	sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
	454	return 1;
	455	}
	456
1da177e4 LT	457	unsigned long get_wchan(struct task_struct *task)
	458	{
	459	unsigned long pc, fp, bias = 0;
	460	unsigned long task_base = (unsigned long) task;
	461	unsigned long ret = 0;
4d7b92ad	462	struct reg_window32 *rw;
1da177e4 LT	463	int count = 0;
	464
	465	if (!task \|\| task == current \|\|
	466	task->state == TASK_RUNNING)
	467	goto out;
	468
d562ef6a	469	fp = task_thread_info(task)->ksp + bias;
1da177e4 LT	470	do {
	471	/* Bogus frame pointer? */
	472	if (fp < (task_base + sizeof(struct thread_info)) \|\|
	473	fp >= (task_base + (2 * PAGE_SIZE)))
	474	break;
4d7b92ad	475	rw = (struct reg_window32 *) fp;
1da177e4 LT	476	pc = rw->ins[7];
	477	if (!in_sched_functions(pc)) {
	478	ret = pc;
	479	goto out;
	480	}
	481	fp = rw->ins[6] + bias;
	482	} while (++count < 16);
	483
	484	out:
	485	return ret;
	486	}
	487