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