arch/m32r/kernel/process.c

   1 /*
   2  *  linux/arch/m32r/kernel/process.c
   3  *
   4  *  Copyright (c) 2001, 2002  Hiroyuki Kondo, Hirokazu Takata,
   5  *                            Hitoshi Yamamoto
   6  *  Taken from sh version.
   7  *    Copyright (C) 1995  Linus Torvalds
   8  *    SuperH version:  Copyright (C) 1999, 2000  Niibe Yutaka & Kaz Kojima
   9  */
  10
  11 #undef DEBUG_PROCESS
  12 #ifdef DEBUG_PROCESS
  13 #define DPRINTK(fmt, args...)  printk("%s:%d:%s: " fmt, __FILE__, __LINE__, \
  14   __func__, ##args)
  15 #else
  16 #define DPRINTK(fmt, args...)
  17 #endif
  18
  19 /*
  20  * This file handles the architecture-dependent parts of process handling..
  21  */
  22
  23 #include <linux/fs.h>
  24 #include <linux/slab.h>
  25 #include <linux/module.h>
  26 #include <linux/ptrace.h>
  27 #include <linux/unistd.h>
  28 #include <linux/hardirq.h>
  29 #include <linux/rcupdate.h>
  30
  31 #include <asm/io.h>
  32 #include <asm/uaccess.h>
  33 #include <asm/mmu_context.h>
  34 #include <asm/elf.h>
  35 #include <asm/m32r.h>
  36
  37 #include <linux/err.h>
  38
  39 /*
  40  * Return saved PC of a blocked thread.
  41  */
  42 unsigned long thread_saved_pc(struct task_struct *tsk)
  43 {
  44         return tsk->thread.lr;
  45 }
  46
  47 void (*pm_power_off)(void) = NULL;
  48 EXPORT_SYMBOL(pm_power_off);
  49
  50 /*
  51  * The idle thread. There's no useful work to be
  52  * done, so just try to conserve power and have a
  53  * low exit latency (ie sit in a loop waiting for
  54  * somebody to say that they'd like to reschedule)
  55  */
  56 void cpu_idle (void)
  57 {
  58         /* endless idle loop with no priority at all */
  59         while (1) {
  60                 rcu_idle_enter();
  61                 while (!need_resched())
  62                         cpu_relax();
  63                 rcu_idle_exit();
  64                 schedule_preempt_disabled();
  65         }
  66 }
  67
  68 void machine_restart(char *__unused)
  69 {
  70 #if defined(CONFIG_PLAT_MAPPI3)
  71         outw(1, (unsigned long)PLD_REBOOT);
  72 #endif
  73
  74         printk("Please push reset button!\n");
  75         while (1)
  76                 cpu_relax();
  77 }
  78
  79 void machine_halt(void)
  80 {
  81         printk("Please push reset button!\n");
  82         while (1)
  83                 cpu_relax();
  84 }
  85
  86 void machine_power_off(void)
  87 {
  88         /* M32R_FIXME */
  89 }
  90
  91 void show_regs(struct pt_regs * regs)
  92 {
  93         printk("\n");
  94         printk("BPC[%08lx]:PSW[%08lx]:LR [%08lx]:FP [%08lx]\n", \
  95           regs->bpc, regs->psw, regs->lr, regs->fp);
  96         printk("BBPC[%08lx]:BBPSW[%08lx]:SPU[%08lx]:SPI[%08lx]\n", \
  97           regs->bbpc, regs->bbpsw, regs->spu, regs->spi);
  98         printk("R0 [%08lx]:R1 [%08lx]:R2 [%08lx]:R3 [%08lx]\n", \
  99           regs->r0, regs->r1, regs->r2, regs->r3);
 100         printk("R4 [%08lx]:R5 [%08lx]:R6 [%08lx]:R7 [%08lx]\n", \
 101           regs->r4, regs->r5, regs->r6, regs->r7);
 102         printk("R8 [%08lx]:R9 [%08lx]:R10[%08lx]:R11[%08lx]\n", \
 103           regs->r8, regs->r9, regs->r10, regs->r11);
 104         printk("R12[%08lx]\n", \
 105           regs->r12);
 106
 107 #if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2)
 108         printk("ACC0H[%08lx]:ACC0L[%08lx]\n", \
 109           regs->acc0h, regs->acc0l);
 110         printk("ACC1H[%08lx]:ACC1L[%08lx]\n", \
 111           regs->acc1h, regs->acc1l);
 112 #elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R)
 113         printk("ACCH[%08lx]:ACCL[%08lx]\n", \
 114           regs->acc0h, regs->acc0l);
 115 #else
 116 #error unknown isa configuration
 117 #endif
 118 }
 119
 120 /*
 121  * Free current thread data structures etc..
 122  */
 123 void exit_thread(void)
 124 {
 125         /* Nothing to do. */
 126         DPRINTK("pid = %d\n", current->pid);
 127 }
 128
 129 void flush_thread(void)
 130 {
 131         DPRINTK("pid = %d\n", current->pid);
 132         memset(&current->thread.debug_trap, 0, sizeof(struct debug_trap));
 133 }
 134
 135 void release_thread(struct task_struct *dead_task)
 136 {
 137         /* do nothing */
 138         DPRINTK("pid = %d\n", dead_task->pid);
 139 }
 140
 141 /* Fill in the fpu structure for a core dump.. */
 142 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
 143 {
 144         return 0; /* Task didn't use the fpu at all. */
 145 }
 146
 147 int copy_thread(unsigned long clone_flags, unsigned long spu,
 148         unsigned long arg, struct task_struct *tsk)
 149 {
 150         struct pt_regs *childregs = task_pt_regs(tsk);
 151         extern void ret_from_fork(void);
 152         extern void ret_from_kernel_thread(void);
 153
 154         if (unlikely(tsk->flags & PF_KTHREAD)) {
 155                 memset(childregs, 0, sizeof(struct pt_regs));
 156                 childregs->psw = M32R_PSW_BIE;
 157                 childregs->r1 = spu;    /* fn */
 158                 childregs->r0 = arg;
 159                 tsk->thread.lr = (unsigned long)ret_from_kernel_thread;
 160         } else {
 161                 /* Copy registers */
 162                 *childregs = *current_pt_regs();
 163                 if (spu)
 164                         childregs->spu = spu;
 165                 childregs->r0 = 0;      /* Child gets zero as return value */
 166                 tsk->thread.lr = (unsigned long)ret_from_fork;
 167         }
 168         tsk->thread.sp = (unsigned long)childregs;
 169
 170         return 0;
 171 }
 172
 173 /*
 174  * These bracket the sleeping functions..
 175  */
 176 #define first_sched     ((unsigned long) scheduling_functions_start_here)
 177 #define last_sched      ((unsigned long) scheduling_functions_end_here)
 178
 179 unsigned long get_wchan(struct task_struct *p)
 180 {
 181         /* M32R_FIXME */
 182         return (0);
 183 }