LXR linux/arch/h8300/kernel/process.c

   1/*
   2 *  linux/arch/h8300/kernel/process.c
   3 *
   4 * Yoshinori Sato <ysato@users.sourceforge.jp>
   5 *
   6 *  Based on:
   7 *
   8 *  linux/arch/m68knommu/kernel/process.c
   9 *
  10 *  Copyright (C) 1998  D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
  11 *                      Kenneth Albanowski <kjahds@kjahds.com>,
  12 *                      The Silver Hammer Group, Ltd.
  13 *
  14 *  linux/arch/m68k/kernel/process.c
  15 *
  16 *  Copyright (C) 1995  Hamish Macdonald
  17 *
  18 *  68060 fixes by Jesper Skov
  19 */
  20
  21/*
  22 * This file handles the architecture-dependent parts of process handling..
  23 */
  24
  25#include <linux/errno.h>
  26#include <linux/module.h>
  27#include <linux/sched.h>
  28#include <linux/kernel.h>
  29#include <linux/mm.h>
  30#include <linux/smp.h>
  31#include <linux/stddef.h>
  32#include <linux/unistd.h>
  33#include <linux/ptrace.h>
  34#include <linux/user.h>
  35#include <linux/interrupt.h>
  36#include <linux/reboot.h>
  37#include <linux/fs.h>
  38#include <linux/slab.h>
  39#include <linux/rcupdate.h>
  40
  41#include <asm/uaccess.h>
  42#include <asm/traps.h>
  43#include <asm/setup.h>
  44#include <asm/pgtable.h>
  45
  46void (*pm_power_off)(void) = NULL;
  47EXPORT_SYMBOL(pm_power_off);
  48
  49asmlinkage void ret_from_fork(void);
  50asmlinkage void ret_from_kernel_thread(void);
  51
  52/*
  53 * The idle loop on an H8/300..
  54 */
  55#if !defined(CONFIG_H8300H_SIM) && !defined(CONFIG_H8S_SIM)
  56void arch_cpu_idle(void)
  57{
  58        local_irq_enable();
  59        /* XXX: race here! What if need_resched() gets set now? */
  60        __asm__("sleep");
  61}
  62#endif
  63
  64void machine_restart(char * __unused)
  65{
  66        local_irq_disable();
  67        __asm__("jmp @@0"); 
  68}
  69
  70void machine_halt(void)
  71{
  72        local_irq_disable();
  73        __asm__("sleep");
  74        for (;;);
  75}
  76
  77void machine_power_off(void)
  78{
  79        local_irq_disable();
  80        __asm__("sleep");
  81        for (;;);
  82}
  83
  84void show_regs(struct pt_regs * regs)
  85{
  86        show_regs_print_info(KERN_DEFAULT);
  87
  88        printk("\nPC: %08lx  Status: %02x",
  89               regs->pc, regs->ccr);
  90        printk("\nORIG_ER0: %08lx ER0: %08lx ER1: %08lx",
  91               regs->orig_er0, regs->er0, regs->er1);
  92        printk("\nER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx",
  93               regs->er2, regs->er3, regs->er4, regs->er5);
  94        printk("\nER6' %08lx ",regs->er6);
  95        if (user_mode(regs))
  96                printk("USP: %08lx\n", rdusp());
  97        else
  98                printk("\n");
  99}
 100
 101void flush_thread(void)
 102{
 103}
 104
 105int copy_thread(unsigned long clone_flags,
 106                unsigned long usp, unsigned long topstk,
 107                 struct task_struct * p)
 108{
 109        struct pt_regs * childregs;
 110
 111        childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
 112
 113        if (unlikely(p->flags & PF_KTHREAD)) {
 114                memset(childregs, 0, sizeof(struct pt_regs));
 115                childregs->retpc = (unsigned long) ret_from_kernel_thread;
 116                childregs->er4 = topstk; /* arg */
 117                childregs->er5 = usp; /* fn */
 118                p->thread.ksp = (unsigned long)childregs;
 119        }
 120        *childregs = *current_pt_regs();
 121        childregs->retpc = (unsigned long) ret_from_fork;
 122        childregs->er0 = 0;
 123        p->thread.usp = usp ?: rdusp();
 124        p->thread.ksp = (unsigned long)childregs;
 125
 126        return 0;
 127}
 128
 129unsigned long thread_saved_pc(struct task_struct *tsk)
 130{
 131        return ((struct pt_regs *)tsk->thread.esp0)->pc;
 132}
 133
 134unsigned long get_wchan(struct task_struct *p)
 135{
 136        unsigned long fp, pc;
 137        unsigned long stack_page;
 138        int count = 0;
 139        if (!p || p == current || p->state == TASK_RUNNING)
 140                return 0;
 141
 142        stack_page = (unsigned long)p;
 143        fp = ((struct pt_regs *)p->thread.ksp)->er6;
 144        do {
 145                if (fp < stack_page+sizeof(struct thread_info) ||
 146                    fp >= 8184+stack_page)
 147                        return 0;
 148                pc = ((unsigned long *)fp)[1];
 149                if (!in_sched_functions(pc))
 150                        return pc;
 151                fp = *(unsigned long *) fp;
 152        } while (count++ < 16);
 153        return 0;
 154}
 155