path: root/arch/sparc/kernel/process.c

/*  $Id: process.c,v 1.161 2002/01/23 11:27:32 davem Exp $
 *  linux/arch/sparc/kernel/process.c
 *
 *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 *  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/kallsyms.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/config.h>
#include <linux/smp.h>
#include <linux/smp_lock.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/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);

/*
 * 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];

/*
 * default_idle is new in 2.5. XXX Review, currently stolen from sparc64.
 */
void default_idle(void)
{
}

#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_SUN4) {
			static int count = HZ;
			static unsigned long last_jiffies;
			static unsigned long last_faults;
			static unsigned long fps;
			unsigned long now;
			unsigned long faults;
			unsigned long flags;

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

			local_irq_save(flags);
			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_restore(flags);
		}

		while((!need_resched()) && pm_idle) {
			(*pm_idle)();
		}

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

#else

/* This is being executed in task 0 'user space'. */
void cpu_idle(void)
{
	/* endless idle loop with no priority at all */
	while(1) {
		if(need_resched()) {
			preempt_enable_no_resched();
			schedule();
			preempt_disable();
			check_pgt_cache();
		}
		barrier(); /* or else gcc optimizes... */
	}
}

#endif

extern char reboot_command [];

extern void (*prom_palette)(int);

/* 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();
	if (!serial_console && prom_palette)
		prom_palette (1);
	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 (!serial_console && prom_palette)
		prom_palette (1);
	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 && (!serial_console || scons_pwroff))
		*auxio_power_register |= AUXIO_POWER_OFF;
#endif
	machine_halt();
}

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]);
		print_symbol("%s\n", 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

#if 0
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