LXR linux/arch/h8300/include/asm/processor.h

   1/*
   2 * include/asm-h8300/processor.h
   3 *
   4 * Copyright (C) 2002 Yoshinori Sato
   5 *
   6 * Based on: linux/asm-m68nommu/processor.h
   7 *
   8 * Copyright (C) 1995 Hamish Macdonald
   9 */
  10
  11#ifndef __ASM_H8300_PROCESSOR_H
  12#define __ASM_H8300_PROCESSOR_H
  13
  14/*
  15 * Default implementation of macro that returns current
  16 * instruction pointer ("program counter").
  17 */
  18#define current_text_addr() ({ __label__ _l; _l: &&_l;})
  19
  20#include <linux/compiler.h>
  21#include <asm/segment.h>
  22#include <asm/fpu.h>
  23#include <asm/ptrace.h>
  24#include <asm/current.h>
  25
  26static inline unsigned long rdusp(void) {
  27        extern unsigned int     sw_usp;
  28        return(sw_usp);
  29}
  30
  31static inline void wrusp(unsigned long usp) {
  32        extern unsigned int     sw_usp;
  33        sw_usp = usp;
  34}
  35
  36/*
  37 * User space process size: 3.75GB. This is hardcoded into a few places,
  38 * so don't change it unless you know what you are doing.
  39 */
  40#define TASK_SIZE       (0xFFFFFFFFUL)
  41
  42#ifdef __KERNEL__
  43#define STACK_TOP       TASK_SIZE
  44#define STACK_TOP_MAX   STACK_TOP
  45#endif
  46
  47/*
  48 * This decides where the kernel will search for a free chunk of vm
  49 * space during mmap's. We won't be using it
  50 */
  51#define TASK_UNMAPPED_BASE      0
  52
  53struct thread_struct {
  54        unsigned long  ksp;             /* kernel stack pointer */
  55        unsigned long  usp;             /* user stack pointer */
  56        unsigned long  ccr;             /* saved status register */
  57        unsigned long  esp0;            /* points to SR of stack frame */
  58        struct {
  59                unsigned short *addr;
  60                unsigned short inst;
  61        } breakinfo;
  62};
  63
  64#define INIT_THREAD  {                                          \
  65        .ksp  = sizeof(init_stack) + (unsigned long)init_stack, \
  66        .usp  = 0,                                              \
  67        .ccr  = PS_S,                                           \
  68        .esp0 = 0,                                              \
  69        .breakinfo = {                                          \
  70                .addr = (unsigned short *)-1,                   \
  71                .inst = 0                                       \
  72        }                                                       \
  73}
  74
  75/*
  76 * Do necessary setup to start up a newly executed thread.
  77 *
  78 * pass the data segment into user programs if it exists,
  79 * it can't hurt anything as far as I can tell
  80 */
  81#if defined(__H8300H__)
  82#define start_thread(_regs, _pc, _usp)                          \
  83do {                                                            \
  84        set_fs(USER_DS);           /* reads from user space */  \
  85        (_regs)->pc = (_pc);                                    \
  86        (_regs)->ccr = 0x00;       /* clear all flags */        \
  87        (_regs)->er5 = current->mm->start_data; /* GOT base */  \
  88        wrusp((unsigned long)(_usp) - sizeof(unsigned long)*3); \
  89} while(0)
  90#endif
  91#if defined(__H8300S__)
  92#define start_thread(_regs, _pc, _usp)                          \
  93do {                                                            \
  94        set_fs(USER_DS);           /* reads from user space */  \
  95        (_regs)->pc = (_pc);                                    \
  96        (_regs)->ccr = 0x00;       /* clear kernel flag */      \
  97        (_regs)->exr = 0x78;       /* enable all interrupts */  \
  98        (_regs)->er5 = current->mm->start_data; /* GOT base */  \
  99        /* 14 = space for retaddr(4), vector(4), er0(4) and ext(2) on stack */ \
 100        wrusp(((unsigned long)(_usp)) - 14);                    \
 101} while(0)
 102#endif
 103
 104/* Forward declaration, a strange C thing */
 105struct task_struct;
 106
 107/* Free all resources held by a thread. */
 108static inline void release_thread(struct task_struct *dead_task)
 109{
 110}
 111
 112extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
 113
 114#define prepare_to_copy(tsk)    do { } while (0)
 115
 116/*
 117 * Free current thread data structures etc..
 118 */
 119static inline void exit_thread(void)
 120{
 121}
 122
 123/*
 124 * Return saved PC of a blocked thread.
 125 */
 126unsigned long thread_saved_pc(struct task_struct *tsk);
 127unsigned long get_wchan(struct task_struct *p);
 128
 129#define KSTK_EIP(tsk)   \
 130    ({                  \
 131        unsigned long eip = 0;   \
 132        if ((tsk)->thread.esp0 > PAGE_SIZE && \
 133            MAP_NR((tsk)->thread.esp0) < max_mapnr) \
 134              eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
 135        eip; })
 136#define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 137
 138#define cpu_relax()    barrier()
 139
 140#endif
 141