[mirror_ubuntu-bionic-kernel.git] / arch / sparc / kernel / process.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/slab.h>
#include <linux/user.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/init.h>

#include <asm/auxio.h>
#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/system.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>

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

#ifndef CONFIG_SMP

#define SUN4C_FAULT_HIGH 100

/*
 * the idle loop on a Sparc... ;)
 */
void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	for (;;) {
		if (ARCH_SUN4C) {
			static int count = HZ;
			static unsigned long last_jiffies;
			static unsigned long last_faults;
			static unsigned long fps;
			unsigned long now;
			unsigned long faults;

			extern unsigned long sun4c_kernel_faults;
			extern void sun4c_grow_kernel_ring(void);

			local_irq_disable();
			now = jiffies;
			count -= (now - last_jiffies);
			last_jiffies = now;
			if (count < 0) {
				count += HZ;
				faults = sun4c_kernel_faults;
				fps = (fps + (faults - last_faults)) >> 1;
				last_faults = faults;
#if 0
				printk("kernel faults / second = %ld\n", fps);
#endif
				if (fps >= SUN4C_FAULT_HIGH) {
					sun4c_grow_kernel_ring();
				}
			}
			local_irq_enable();
		}

		if (pm_idle) {
			while (!need_resched())
				(*pm_idle)();
		} else {
			while (!need_resched())
				cpu_relax();
		}
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
		check_pgt_cache();
	}
}

#else

/* This is being executed in task 0 'user space'. */
void cpu_idle(void)
{
        set_thread_flag(TIF_POLLING_NRFLAG);
	/* endless idle loop with no priority at all */
	while(1) {
		while (!need_resched())
			cpu_relax();
		preempt_enable_no_resched();
		schedule();
		preempt_disable();
		check_pgt_cache();
	}
}

#endif

/* 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)
{
#ifdef CONFIG_SUN_AUXIO
	if (auxio_power_register &&
	    (strcmp(of_console_device->type, "serial") || scons_pwroff))
		*auxio_power_register |= AUXIO_POWER_OFF;
#endif
	machine_halt();
}

#if 0

static DEFINE_SPINLOCK(sparc_backtrace_lock);

void __show_backtrace(unsigned long fp)
{
	struct reg_window *rw;
	unsigned long flags;
	int cpu = smp_processor_id();

	spin_lock_irqsave(&sparc_backtrace_lock, flags);

	rw = (struct reg_window *)fp;
        while(rw && (((unsigned long) rw) >= PAGE_OFFSET) &&
            !(((unsigned long) rw) & 0x7)) {
		printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] "
		       "FP[%08lx] CALLER[%08lx]: ", cpu,
		       rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
		       rw->ins[4], rw->ins[5],
		       rw->ins[6],
		       rw->ins[7]);
		printk("%pS\n", (void *) rw->ins[7]);
		rw = (struct reg_window *) rw->ins[6];
	}
	spin_unlock_irqrestore(&sparc_backtrace_lock, flags);
}

#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
#define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp))

void show_backtrace(void)
{
	unsigned long fp;

	__SAVE; __SAVE; __SAVE; __SAVE;
	__SAVE; __SAVE; __SAVE; __SAVE;
	__RESTORE; __RESTORE; __RESTORE; __RESTORE;
	__RESTORE; __RESTORE; __RESTORE; __RESTORE;

	__GET_FP(fp);

	__show_backtrace(fp);
}

#ifdef CONFIG_SMP
void smp_show_backtrace_all_cpus(void)
{
	xc0((smpfunc_t) show_backtrace);
	show_backtrace();
}
#endif

void show_stackframe(struct sparc_stackf *sf)
{
	unsigned long size;
	unsigned long *stk;
	int i;

	printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx "
	       "l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n",
	       sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
	       sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
	printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx "
	       "i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n",
	       sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
	       sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
	printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx "
	       "x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n",
	       (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
	       sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
	       sf->xxargs[0]);
	size = ((unsigned long)sf->fp) - ((unsigned long)sf);
	size -= STACKFRAME_SZ;
	stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
	i = 0;
	do {
		printk("s%d: %08lx\n", i++, *stk++);
	} while ((size -= sizeof(unsigned long)));
}
#endif

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

        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_window *rw;
	int count = 0;

	if (tsk != NULL)
		task_base = (unsigned long) task_stack_page(tsk);
	else
		task_base = (unsigned long) current_thread_info();

	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_window *) fp;
		pc = rw->ins[7];
		printk("[%08lx : ", pc);
		printk("%pS ] ", (void *) pc);
		fp = rw->ins[6];
	} while (++count < 16);
	printk("\n");
}

void dump_stack(void)
{
	unsigned long *ksp;

	__asm__ __volatile__("mov	%%fp, %0"
			     : "=r" (ksp));
	show_stack(current, ksp);
}

EXPORT_SYMBOL(dump_stack);

/*
 * 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
	}

	/* Now, this task is no longer a kernel thread. */
	current->thread.current_ds = USER_DS;
	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,
		      regs, 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);

int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
		unsigned long unused,
		struct task_struct *p, struct pt_regs *regs)
{
	struct thread_info *ti = task_thread_info(p);
	struct pt_regs *childregs;
	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);
#ifdef CONFIG_SMP
		clear_thread_flag(TIF_USEDFPU);
#endif
	}

	/*
	 *  p->thread_info         new_stack   childregs
	 *  !                      !           !             {if(PSR_PS) }
	 *  V                      V (stk.fr.) V  (pt_regs)  { (stk.fr.) }
	 *  +----- - - - - - ------+===========+============={+==========}+
	 */
	new_stack = task_stack_page(p) + THREAD_SIZE;
	if (regs->psr & PSR_PS)
		new_stack -= STACKFRAME_SZ;
	new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
	memcpy(new_stack, (char *)regs - STACKFRAME_SZ, 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;
	ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
	ti->kpsr = current->thread.fork_kpsr | PSR_PIL;
	ti->kwim = current->thread.fork_kwim;

	if(regs->psr & PSR_PS) {
		extern struct pt_regs fake_swapper_regs;

		p->thread.kregs = &fake_swapper_regs;
		new_stack += STACKFRAME_SZ + TRACEREG_SZ;
		childregs->u_regs[UREG_FP] = (unsigned long) new_stack;
		p->thread.flags |= SPARC_FLAG_KTHREAD;
		p->thread.current_ds = KERNEL_DS;
		memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);
		childregs->u_regs[UREG_G6] = (unsigned long) ti;
	} else {
		p->thread.kregs = childregs;
		childregs->u_regs[UREG_FP] = sp;
		p->thread.flags &= ~SPARC_FLAG_KTHREAD;
		p->thread.current_ds = USER_DS;

		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 & ~0x7UL);
			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;
#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;
}

/*
 * sparc_execve() executes a new program after the asm stub has set
 * things up for us.  This should basically do what I want it to.
 */
asmlinkage int sparc_execve(struct pt_regs *regs)
{
	int error, base = 0;
	char *filename;

	/* Check for indirect call. */
	if(regs->u_regs[UREG_G1] == 0)
		base = 1;

	filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
	error = PTR_ERR(filename);
	if(IS_ERR(filename))
		goto out;
	error = do_execve(filename,
			  (char __user * __user *)regs->u_regs[base + UREG_I1],
			  (char __user * __user *)regs->u_regs[base + UREG_I2],
			  regs);
	putname(filename);
out:
	return error;
}

/*
 * This is the mechanism for creating a new kernel thread.
 *
 * NOTE! Only a kernel-only process(ie the swapper or direct descendants
 * who haven't done an "execve()") should use this: it will work within
 * a system call from a "real" process, but the process memory space will
 * not be freed until both the parent and the child have exited.
 */
pid_t kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
	long retval;

	__asm__ __volatile__("mov %4, %%g2\n\t"    /* Set aside fn ptr... */
			     "mov %5, %%g3\n\t"    /* and arg. */
			     "mov %1, %%g1\n\t"
			     "mov %2, %%o0\n\t"    /* Clone flags. */
			     "mov 0, %%o1\n\t"     /* usp arg == 0 */
			     "t 0x10\n\t"          /* Linux/Sparc clone(). */
			     "cmp %%o1, 0\n\t"
			     "be 1f\n\t"           /* The parent, just return. */
			     " nop\n\t"            /* Delay slot. */
			     "jmpl %%g2, %%o7\n\t" /* Call the function. */
			     " mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
			     "mov %3, %%g1\n\t"
			     "t 0x10\n\t"          /* Linux/Sparc exit(). */
			     /* Notreached by child. */
			     "1: mov %%o0, %0\n\t" :
			     "=r" (retval) :
			     "i" (__NR_clone), "r" (flags | CLONE_VM | CLONE_UNTRACED),
			     "i" (__NR_exit),  "r" (fn), "r" (arg) :
			     "g1", "g2", "g3", "o0", "o1", "memory", "cc");
	return retval;
}

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_window *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_window *) 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>
	20	#include <linux/slab.h>
	21	#include <linux/user.h>
1da177e4	22	#include <linux/smp.h>
1da177e4 LT	23	#include <linux/reboot.h>
	24	#include <linux/delay.h>
	25	#include <linux/pm.h>
	26	#include <linux/init.h>
	27
	28	#include <asm/auxio.h>
	29	#include <asm/oplib.h>
	30	#include <asm/uaccess.h>
	31	#include <asm/system.h>
	32	#include <asm/page.h>
	33	#include <asm/pgalloc.h>
	34	#include <asm/pgtable.h>
	35	#include <asm/delay.h>
	36	#include <asm/processor.h>
	37	#include <asm/psr.h>
	38	#include <asm/elf.h>
c73fcc84	39	#include <asm/prom.h>
1da177e4 LT	40	#include <asm/unistd.h>
	41
	42	/*
	43	* Power management idle function
	44	* Set in pm platform drivers (apc.c and pmc.c)
	45	*/
	46	void (*pm_idle)(void);
	47
	48	/*
	49	* Power-off handler instantiation for pm.h compliance
	50	* This is done via auxio, but could be used as a fallback
	51	* handler when auxio is not present-- unused for now...
	52	*/
304cd3ef	53	void (*pm_power_off)(void) = machine_power_off;
89eb1693	54	EXPORT_SYMBOL(pm_power_off);
1da177e4 LT	55
	56	/*
	57	* sysctl - toggle power-off restriction for serial console
	58	* systems in machine_power_off()
	59	*/
	60	int scons_pwroff = 1;
	61
	62	extern void fpsave(unsigned long , unsigned long , void , unsigned long );
	63
	64	struct task_struct *last_task_used_math = NULL;
	65	struct thread_info *current_set[NR_CPUS];
	66
1da177e4 LT	67	#ifndef CONFIG_SMP
	68
	69	#define SUN4C_FAULT_HIGH 100
	70
	71	/*
	72	* the idle loop on a Sparc... ;)
	73	*/
	74	void cpu_idle(void)
	75	{
1da177e4 LT	76	/* endless idle loop with no priority at all */
1da177e4 LT	77	for (;;) {
5110bd21	78	if (ARCH_SUN4C) {
1da177e4 LT	79	static int count = HZ;
	80	static unsigned long last_jiffies;
	81	static unsigned long last_faults;
	82	static unsigned long fps;
	83	unsigned long now;
	84	unsigned long faults;
1da177e4 LT	85
	86	extern unsigned long sun4c_kernel_faults;
	87	extern void sun4c_grow_kernel_ring(void);
	88
64c7c8f8	89	local_irq_disable();
1da177e4 LT	90	now = jiffies;
	91	count -= (now - last_jiffies);
	92	last_jiffies = now;
	93	if (count < 0) {
	94	count += HZ;
	95	faults = sun4c_kernel_faults;
	96	fps = (fps + (faults - last_faults)) >> 1;
	97	last_faults = faults;
	98	#if 0
	99	printk("kernel faults / second = %ld\n", fps);
	100	#endif
	101	if (fps >= SUN4C_FAULT_HIGH) {
	102	sun4c_grow_kernel_ring();
	103	}
	104	}
64c7c8f8	105	local_irq_enable();
1da177e4 LT	106	}
1da177e4 LT	107
64c7c8f8 NP	108	if (pm_idle) {
	109	while (!need_resched())
	110	(*pm_idle)();
	111	} else {
	112	while (!need_resched())
	113	cpu_relax();
1da177e4	114	}
5bfb5d69	115	preempt_enable_no_resched();
1da177e4	116	schedule();
5bfb5d69	117	preempt_disable();
1da177e4 LT	118	check_pgt_cache();
1da177e4 LT	119	}
1da177e4 LT	120	}
	121
	122	#else
	123
	124	/* This is being executed in task 0 'user space'. */
	125	void cpu_idle(void)
	126	{
64c7c8f8	127	set_thread_flag(TIF_POLLING_NRFLAG);
1da177e4 LT	128	/* endless idle loop with no priority at all */
1da177e4 LT	129	while(1) {
64c7c8f8 NP	130	while (!need_resched())
	131	cpu_relax();
	132	preempt_enable_no_resched();
	133	schedule();
	134	preempt_disable();
	135	check_pgt_cache();
1da177e4 LT	136	}
	137	}
	138
	139	#endif
	140
1da177e4 LT	141	/* XXX cli/sti -> local_irq_xxx here, check this works once SMP is fixed. */
	142	void machine_halt(void)
	143	{
	144	local_irq_enable();
	145	mdelay(8);
	146	local_irq_disable();
1da177e4 LT	147	prom_halt();
	148	panic("Halt failed!");
	149	}
	150
1da177e4 LT	151	void machine_restart(char * cmd)
	152	{
	153	char *p;
	154
	155	local_irq_enable();
	156	mdelay(8);
	157	local_irq_disable();
	158
	159	p = strchr (reboot_command, '\n');
	160	if (p) *p = 0;
1da177e4 LT	161	if (cmd)
	162	prom_reboot(cmd);
	163	if (*reboot_command)
	164	prom_reboot(reboot_command);
	165	prom_feval ("reset");
	166	panic("Reboot failed!");
	167	}
	168
1da177e4 LT	169	void machine_power_off(void)
	170	{
	171	#ifdef CONFIG_SUN_AUXIO
c73fcc84 DM	172	if (auxio_power_register &&
c73fcc84 DM	173	(strcmp(of_console_device->type, "serial") \|\| scons_pwroff))
1da177e4 LT	174	*auxio_power_register \|= AUXIO_POWER_OFF;
	175	#endif
	176	machine_halt();
	177	}
	178
c61c65cd AB	179	#if 0
c61c65cd AB	180
1da177e4 LT	181	static DEFINE_SPINLOCK(sparc_backtrace_lock);
	182
	183	void __show_backtrace(unsigned long fp)
	184	{
	185	struct reg_window *rw;
	186	unsigned long flags;
	187	int cpu = smp_processor_id();
	188
	189	spin_lock_irqsave(&sparc_backtrace_lock, flags);
	190
	191	rw = (struct reg_window *)fp;
	192	while(rw && (((unsigned long) rw) >= PAGE_OFFSET) &&
	193	!(((unsigned long) rw) & 0x7)) {
	194	printk("CPU[%d]: ARGS[%08lx,%08lx,%08lx,%08lx,%08lx,%08lx] "
	195	"FP[%08lx] CALLER[%08lx]: ", cpu,
	196	rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
	197	rw->ins[4], rw->ins[5],
	198	rw->ins[6],
	199	rw->ins[7]);
4fe3ebec	200	printk("%pS\n", (void *) rw->ins[7]);
1da177e4 LT	201	rw = (struct reg_window *) rw->ins[6];
	202	}
	203	spin_unlock_irqrestore(&sparc_backtrace_lock, flags);
	204	}
	205
	206	#define __SAVE __asm__ __volatile__("save %sp, -0x40, %sp\n\t")
	207	#define __RESTORE __asm__ __volatile__("restore %g0, %g0, %g0\n\t")
	208	#define __GET_FP(fp) __asm__ __volatile__("mov %%i6, %0" : "=r" (fp))
	209
	210	void show_backtrace(void)
	211	{
	212	unsigned long fp;
	213
	214	__SAVE; __SAVE; __SAVE; __SAVE;
	215	__SAVE; __SAVE; __SAVE; __SAVE;
	216	__RESTORE; __RESTORE; __RESTORE; __RESTORE;
	217	__RESTORE; __RESTORE; __RESTORE; __RESTORE;
	218
	219	__GET_FP(fp);
	220
	221	__show_backtrace(fp);
	222	}
	223
	224	#ifdef CONFIG_SMP
	225	void smp_show_backtrace_all_cpus(void)
	226	{
	227	xc0((smpfunc_t) show_backtrace);
	228	show_backtrace();
	229	}
	230	#endif
	231
1da177e4 LT	232	void show_stackframe(struct sparc_stackf *sf)
	233	{
	234	unsigned long size;
	235	unsigned long *stk;
	236	int i;
	237
	238	printk("l0: %08lx l1: %08lx l2: %08lx l3: %08lx "
	239	"l4: %08lx l5: %08lx l6: %08lx l7: %08lx\n",
	240	sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
	241	sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
	242	printk("i0: %08lx i1: %08lx i2: %08lx i3: %08lx "
	243	"i4: %08lx i5: %08lx fp: %08lx i7: %08lx\n",
	244	sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
	245	sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
	246	printk("sp: %08lx x0: %08lx x1: %08lx x2: %08lx "
	247	"x3: %08lx x4: %08lx x5: %08lx xx: %08lx\n",
	248	(unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
	249	sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
	250	sf->xxargs[0]);
	251	size = ((unsigned long)sf->fp) - ((unsigned long)sf);
	252	size -= STACKFRAME_SZ;
	253	stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
	254	i = 0;
	255	do {
	256	printk("s%d: %08lx\n", i++, *stk++);
	257	} while ((size -= sizeof(unsigned long)));
	258	}
	259	#endif
	260
	261	void show_regs(struct pt_regs *r)
	262	{
	263	struct reg_window rw = (struct reg_window ) r->u_regs[14];
	264
	265	printk("PSR: %08lx PC: %08lx NPC: %08lx Y: %08lx %s\n",
	266	r->psr, r->pc, r->npc, r->y, print_tainted());
4fe3ebec	267	printk("PC: <%pS>\n", (void *) r->pc);
1da177e4 LT	268	printk("%%G: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	269	r->u_regs[0], r->u_regs[1], r->u_regs[2], r->u_regs[3],
	270	r->u_regs[4], r->u_regs[5], r->u_regs[6], r->u_regs[7]);
	271	printk("%%O: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	272	r->u_regs[8], r->u_regs[9], r->u_regs[10], r->u_regs[11],
	273	r->u_regs[12], r->u_regs[13], r->u_regs[14], r->u_regs[15]);
4fe3ebec	274	printk("RPC: <%pS>\n", (void *) r->u_regs[15]);
1da177e4 LT	275
	276	printk("%%L: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	277	rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
	278	rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
	279	printk("%%I: %08lx %08lx %08lx %08lx %08lx %08lx %08lx %08lx\n",
	280	rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
	281	rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
	282	}
	283
	284	/*
	285	* The show_stack is an external API which we do not use ourselves.
	286	* The oops is printed in die_if_kernel.
	287	*/
	288	void show_stack(struct task_struct tsk, unsigned long _ksp)
	289	{
	290	unsigned long pc, fp;
	291	unsigned long task_base;
	292	struct reg_window *rw;
	293	int count = 0;
	294
	295	if (tsk != NULL)
36483c6b	296	task_base = (unsigned long) task_stack_page(tsk);
1da177e4 LT	297	else
	298	task_base = (unsigned long) current_thread_info();
	299
	300	fp = (unsigned long) _ksp;
	301	do {
	302	/* Bogus frame pointer? */
	303	if (fp < (task_base + sizeof(struct thread_info)) \|\|
	304	fp >= (task_base + (PAGE_SIZE << 1)))
	305	break;
	306	rw = (struct reg_window *) fp;
	307	pc = rw->ins[7];
	308	printk("[%08lx : ", pc);
4fe3ebec	309	printk("%pS ] ", (void *) pc);
1da177e4 LT	310	fp = rw->ins[6];
	311	} while (++count < 16);
	312	printk("\n");
	313	}
	314
24dc6ead TC	315	void dump_stack(void)
	316	{
	317	unsigned long *ksp;
	318
	319	__asm__ __volatile__("mov %%fp, %0"
	320	: "=r" (ksp));
	321	show_stack(current, ksp);
	322	}
	323
	324	EXPORT_SYMBOL(dump_stack);
	325
1da177e4 LT	326	/*
	327	* Note: sparc64 has a pretty intricated thread_saved_pc, check it out.
	328	*/
	329	unsigned long thread_saved_pc(struct task_struct *tsk)
	330	{
d562ef6a	331	return task_thread_info(tsk)->kpc;
1da177e4 LT	332	}
	333
	334	/*
	335	* Free current thread data structures etc..
	336	*/
	337	void exit_thread(void)
	338	{
	339	#ifndef CONFIG_SMP
	340	if(last_task_used_math == current) {
	341	#else
54f565ea	342	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	343	#endif
	344	/* Keep process from leaving FPU in a bogon state. */
	345	put_psr(get_psr() \| PSR_EF);
	346	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	347	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	348	#ifndef CONFIG_SMP
	349	last_task_used_math = NULL;
	350	#else
54f565ea	351	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	352	#endif
	353	}
	354	}
	355
	356	void flush_thread(void)
	357	{
	358	current_thread_info()->w_saved = 0;
	359
1da177e4 LT	360	#ifndef CONFIG_SMP
	361	if(last_task_used_math == current) {
	362	#else
54f565ea	363	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	364	#endif
	365	/* Clean the fpu. */
	366	put_psr(get_psr() \| PSR_EF);
	367	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	368	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	369	#ifndef CONFIG_SMP
	370	last_task_used_math = NULL;
	371	#else
54f565ea	372	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	373	#endif
	374	}
	375
	376	/* Now, this task is no longer a kernel thread. */
	377	current->thread.current_ds = USER_DS;
	378	if (current->thread.flags & SPARC_FLAG_KTHREAD) {
	379	current->thread.flags &= ~SPARC_FLAG_KTHREAD;
	380
	381	/* We must fixup kregs as well. */
	382	/* XXX This was not fixed for ti for a while, worked. Unused? */
	383	current->thread.kregs = (struct pt_regs *)
36483c6b	384	(task_stack_page(current) + (THREAD_SIZE - TRACEREG_SZ));
1da177e4 LT	385	}
	386	}
	387
64d329ee	388	static inline struct sparc_stackf __user *
1da177e4 LT	389	clone_stackframe(struct sparc_stackf __user *dst,
	390	struct sparc_stackf __user *src)
	391	{
	392	unsigned long size, fp;
	393	struct sparc_stackf *tmp;
	394	struct sparc_stackf __user *sp;
	395
	396	if (get_user(tmp, &src->fp))
	397	return NULL;
	398
	399	fp = (unsigned long) tmp;
	400	size = (fp - ((unsigned long) src));
	401	fp = (unsigned long) dst;
	402	sp = (struct sparc_stackf __user *)(fp - size);
	403
	404	/* do_fork() grabs the parent semaphore, we must release it
	405	* temporarily so we can build the child clone stack frame
	406	* without deadlocking.
	407	*/
	408	if (__copy_user(sp, src, size))
	409	sp = NULL;
	410	else if (put_user(fp, &sp->fp))
	411	sp = NULL;
	412
	413	return sp;
	414	}
	415
	416	asmlinkage int sparc_do_fork(unsigned long clone_flags,
	417	unsigned long stack_start,
	418	struct pt_regs *regs,
	419	unsigned long stack_size)
	420	{
	421	unsigned long parent_tid_ptr, child_tid_ptr;
1e38c126 DM	422	unsigned long orig_i1 = regs->u_regs[UREG_I1];
1e38c126 DM	423	long ret;
1da177e4 LT	424
	425	parent_tid_ptr = regs->u_regs[UREG_I2];
	426	child_tid_ptr = regs->u_regs[UREG_I4];
	427
1e38c126 DM	428	ret = do_fork(clone_flags, stack_start,
	429	regs, stack_size,
	430	(int __user *) parent_tid_ptr,
	431	(int __user *) child_tid_ptr);
	432
	433	/* If we get an error and potentially restart the system
	434	* call, we're screwed because copy_thread() clobbered
	435	* the parent's %o1. So detect that case and restore it
	436	* here.
	437	*/
	438	if ((unsigned long)ret >= -ERESTART_RESTARTBLOCK)
	439	regs->u_regs[UREG_I1] = orig_i1;
	440
	441	return ret;
1da177e4 LT	442	}
	443
	444	/* Copy a Sparc thread. The fork() return value conventions
	445	* under SunOS are nothing short of bletcherous:
	446	* Parent --> %o0 == childs pid, %o1 == 0
	447	* Child --> %o0 == parents pid, %o1 == 1
	448	*
	449	* NOTE: We have a separate fork kpsr/kwim because
	450	* the parent could change these values between
	451	* sys_fork invocation and when we reach here
	452	* if the parent should sleep while trying to
	453	* allocate the task_struct and kernel stack in
	454	* do_fork().
	455	* XXX See comment above sys_vfork in sparc64. todo.
	456	*/
	457	extern void ret_from_fork(void);
	458
	459	int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
	460	unsigned long unused,
	461	struct task_struct p, struct pt_regs regs)
	462	{
36483c6b	463	struct thread_info *ti = task_thread_info(p);
1da177e4 LT	464	struct pt_regs *childregs;
	465	char *new_stack;
	466
	467	#ifndef CONFIG_SMP
	468	if(last_task_used_math == current) {
	469	#else
54f565ea	470	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	471	#endif
	472	put_psr(get_psr() \| PSR_EF);
	473	fpsave(&p->thread.float_regs[0], &p->thread.fsr,
	474	&p->thread.fpqueue[0], &p->thread.fpqdepth);
	475	#ifdef CONFIG_SMP
54f565ea	476	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	477	#endif
	478	}
	479
	480	/*
	481	* p->thread_info new_stack childregs
	482	* ! ! ! {if(PSR_PS) }
	483	* V V (stk.fr.) V (pt_regs) { (stk.fr.) }
	484	* +----- - - - - - ------+===========+============={+==========}+
	485	*/
36483c6b	486	new_stack = task_stack_page(p) + THREAD_SIZE;
1da177e4 LT	487	if (regs->psr & PSR_PS)
	488	new_stack -= STACKFRAME_SZ;
	489	new_stack -= STACKFRAME_SZ + TRACEREG_SZ;
	490	memcpy(new_stack, (char *)regs - STACKFRAME_SZ, STACKFRAME_SZ + TRACEREG_SZ);
	491	childregs = (struct pt_regs *) (new_stack + STACKFRAME_SZ);
	492
	493	/*
	494	* A new process must start with interrupts closed in 2.5,
	495	* because this is how Mingo's scheduler works (see schedule_tail
	496	* and finish_arch_switch). If we do not do it, a timer interrupt hits
	497	* before we unlock, attempts to re-take the rq->lock, and then we die.
	498	* Thus, kpsr\|=PSR_PIL.
	499	*/
	500	ti->ksp = (unsigned long) new_stack;
	501	ti->kpc = (((unsigned long) ret_from_fork) - 0x8);
	502	ti->kpsr = current->thread.fork_kpsr \| PSR_PIL;
	503	ti->kwim = current->thread.fork_kwim;
	504
	505	if(regs->psr & PSR_PS) {
	506	extern struct pt_regs fake_swapper_regs;
	507
	508	p->thread.kregs = &fake_swapper_regs;
	509	new_stack += STACKFRAME_SZ + TRACEREG_SZ;
	510	childregs->u_regs[UREG_FP] = (unsigned long) new_stack;
	511	p->thread.flags \|= SPARC_FLAG_KTHREAD;
	512	p->thread.current_ds = KERNEL_DS;
	513	memcpy(new_stack, (void *)regs->u_regs[UREG_FP], STACKFRAME_SZ);
	514	childregs->u_regs[UREG_G6] = (unsigned long) ti;
	515	} else {
	516	p->thread.kregs = childregs;
	517	childregs->u_regs[UREG_FP] = sp;
	518	p->thread.flags &= ~SPARC_FLAG_KTHREAD;
	519	p->thread.current_ds = USER_DS;
	520
	521	if (sp != regs->u_regs[UREG_FP]) {
	522	struct sparc_stackf __user *childstack;
	523	struct sparc_stackf __user *parentstack;
	524
	525	/*
	526	* This is a clone() call with supplied user stack.
	527	* Set some valid stack frames to give to the child.
	528	*/
	529	childstack = (struct sparc_stackf __user *)
	530	(sp & ~0x7UL);
	531	parentstack = (struct sparc_stackf __user *)
	532	regs->u_regs[UREG_FP];
	533
	534	#if 0
	535	printk("clone: parent stack:\n");
	536	show_stackframe(parentstack);
	537	#endif
	538
	539	childstack = clone_stackframe(childstack, parentstack);
	540	if (!childstack)
	541	return -EFAULT;
	542
	543	#if 0
	544	printk("clone: child stack:\n");
	545	show_stackframe(childstack);
	546	#endif
	547
	548	childregs->u_regs[UREG_FP] = (unsigned long)childstack;
	549	}
	550	}
551
552	#ifdef CONFIG_SMP
553	/* FPU must be disabled on SMP. */
554	childregs->psr &= ~PSR_EF;
555	#endif
556
557	/* Set the return value for the child. */
558	childregs->u_regs[UREG_I0] = current->pid;
559	childregs->u_regs[UREG_I1] = 1;
560
561	/* Set the return value for the parent. */
562	regs->u_regs[UREG_I1] = 0;
563
564	if (clone_flags & CLONE_SETTLS)
565	childregs->u_regs[UREG_G7] = regs->u_regs[UREG_I3];
566
567	return 0;
568	}
569
1da177e4 LT	570	/*
	571	* fill in the fpu structure for a core dump.
	572	*/
	573	int dump_fpu (struct pt_regs * regs, elf_fpregset_t * fpregs)
	574	{
	575	if (used_math()) {
	576	memset(fpregs, 0, sizeof(*fpregs));
	577	fpregs->pr_q_entrysize = 8;
	578	return 1;
	579	}
	580	#ifdef CONFIG_SMP
54f565ea	581	if (test_thread_flag(TIF_USEDFPU)) {
1da177e4 LT	582	put_psr(get_psr() \| PSR_EF);
	583	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	584	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	585	if (regs != NULL) {
	586	regs->psr &= ~(PSR_EF);
54f565ea	587	clear_thread_flag(TIF_USEDFPU);
1da177e4 LT	588	}
	589	}
	590	#else
	591	if (current == last_task_used_math) {
	592	put_psr(get_psr() \| PSR_EF);
	593	fpsave(&current->thread.float_regs[0], &current->thread.fsr,
	594	&current->thread.fpqueue[0], &current->thread.fpqdepth);
	595	if (regs != NULL) {
	596	regs->psr &= ~(PSR_EF);
	597	last_task_used_math = NULL;
	598	}
	599	}
	600	#endif
	601	memcpy(&fpregs->pr_fr.pr_regs[0],
	602	&current->thread.float_regs[0],
	603	(sizeof(unsigned long) * 32));
	604	fpregs->pr_fsr = current->thread.fsr;
	605	fpregs->pr_qcnt = current->thread.fpqdepth;
	606	fpregs->pr_q_entrysize = 8;
	607	fpregs->pr_en = 1;
	608	if(fpregs->pr_qcnt != 0) {
	609	memcpy(&fpregs->pr_q[0],
	610	&current->thread.fpqueue[0],
	611	sizeof(struct fpq) * fpregs->pr_qcnt);
	612	}
	613	/* Zero out the rest. */
	614	memset(&fpregs->pr_q[fpregs->pr_qcnt], 0,
	615	sizeof(struct fpq) * (32 - fpregs->pr_qcnt));
	616	return 1;
	617	}
	618
	619	/*
	620	* sparc_execve() executes a new program after the asm stub has set
	621	* things up for us. This should basically do what I want it to.
	622	*/
	623	asmlinkage int sparc_execve(struct pt_regs *regs)
	624	{
	625	int error, base = 0;
	626	char *filename;
	627
	628	/* Check for indirect call. */
	629	if(regs->u_regs[UREG_G1] == 0)
	630	base = 1;
	631
	632	filename = getname((char __user *)regs->u_regs[base + UREG_I0]);
	633	error = PTR_ERR(filename);
	634	if(IS_ERR(filename))
	635	goto out;
	636	error = do_execve(filename,
	637	(char __user * __user *)regs->u_regs[base + UREG_I1],
	638	(char __user * __user *)regs->u_regs[base + UREG_I2],
	639	regs);
	640	putname(filename);
1da177e4 LT	641	out:
	642	return error;
	643	}
	644
	645	/*
	646	* This is the mechanism for creating a new kernel thread.
	647	*
	648	* NOTE! Only a kernel-only process(ie the swapper or direct descendants
	649	* who haven't done an "execve()") should use this: it will work within
	650	* a system call from a "real" process, but the process memory space will
d1a78c32	651	* not be freed until both the parent and the child have exited.
1da177e4 LT	652	*/
	653	pid_t kernel_thread(int (fn)(void ), void * arg, unsigned long flags)
	654	{
	655	long retval;
	656
	657	__asm__ __volatile__("mov %4, %%g2\n\t" /* Set aside fn ptr... */
	658	"mov %5, %%g3\n\t" /* and arg. */
	659	"mov %1, %%g1\n\t"
	660	"mov %2, %%o0\n\t" /* Clone flags. */
	661	"mov 0, %%o1\n\t" /* usp arg == 0 */
	662	"t 0x10\n\t" /* Linux/Sparc clone(). */
	663	"cmp %%o1, 0\n\t"
	664	"be 1f\n\t" /* The parent, just return. */
	665	" nop\n\t" /* Delay slot. */
	666	"jmpl %%g2, %%o7\n\t" /* Call the function. */
	667	" mov %%g3, %%o0\n\t" /* Get back the arg in delay. */
	668	"mov %3, %%g1\n\t"
	669	"t 0x10\n\t" /* Linux/Sparc exit(). */
	670	/* Notreached by child. */
	671	"1: mov %%o0, %0\n\t" :
	672	"=r" (retval) :
	673	"i" (__NR_clone), "r" (flags \| CLONE_VM \| CLONE_UNTRACED),
	674	"i" (__NR_exit), "r" (fn), "r" (arg) :
	675	"g1", "g2", "g3", "o0", "o1", "memory", "cc");
	676	return retval;
	677	}
	678
	679	unsigned long get_wchan(struct task_struct *task)
	680	{
	681	unsigned long pc, fp, bias = 0;
	682	unsigned long task_base = (unsigned long) task;
	683	unsigned long ret = 0;
	684	struct reg_window *rw;
	685	int count = 0;
	686
	687	if (!task \|\| task == current \|\|
	688	task->state == TASK_RUNNING)
	689	goto out;
	690
d562ef6a	691	fp = task_thread_info(task)->ksp + bias;
1da177e4 LT	692	do {
	693	/* Bogus frame pointer? */
	694	if (fp < (task_base + sizeof(struct thread_info)) \|\|
	695	fp >= (task_base + (2 * PAGE_SIZE)))
	696	break;
	697	rw = (struct reg_window *) fp;
	698	pc = rw->ins[7];
	699	if (!in_sched_functions(pc)) {
	700	ret = pc;
	701	goto out;
	702	}
	703	fp = rw->ins[6] + bias;
	704	} while (++count < 16);
	705
	706	out:
	707	return ret;
	708	}
	709