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/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 #ifdef __KERNEL__
  42 #define STACK_TOP       TASK_SIZE
  43 #define STACK_TOP_MAX   STACK_TOP
  44 #endif
  45
  46 /*
  47  * This decides where the kernel will search for a free chunk of vm
  48  * space during mmap's. We won't be using it
  49  */
  50 #define TASK_UNMAPPED_BASE      0
  51
  52 struct thread_struct {
  53         unsigned long  ksp;             /* kernel stack pointer */
  54         unsigned long  usp;             /* user stack pointer */
  55         unsigned long  ccr;             /* saved status register */
  56         unsigned long  esp0;            /* points to SR of stack frame */
  57         struct {
  58                 unsigned short *addr;
  59                 unsigned short inst;
  60         } breakinfo;
  61 };
  62
  63 #define INIT_THREAD  {                                          \
  64         .ksp  = sizeof(init_stack) + (unsigned long)init_stack, \
  65         .usp  = 0,                                              \
  66         .ccr  = PS_S,                                           \
  67         .esp0 = 0,                                              \
  68         .breakinfo = {                                          \
  69                 .addr = (unsigned short *)-1,                   \
  70                 .inst = 0                                       \
  71         }                                                       \
  72 }
  73
  74 /*
  75  * Do necessary setup to start up a newly executed thread.
  76  *
  77  * pass the data segment into user programs if it exists,
  78  * it can't hurt anything as far as I can tell
  79  */
  80 #if defined(CONFIG_CPU_H8300H)
  81 #define start_thread(_regs, _pc, _usp)                          \
  82 do {                                                            \
  83         (_regs)->pc = (_pc);                                    \
  84         (_regs)->ccr = 0x00;       /* clear all flags */        \
  85         (_regs)->er5 = current->mm->start_data; /* GOT base */  \
  86         wrusp((unsigned long)(_usp) - sizeof(unsigned long)*3); \
  87 } while(0)
  88 #endif
  89 #if defined(CONFIG_CPU_H8S)
  90 #define start_thread(_regs, _pc, _usp)                          \
  91 do {                                                            \
  92         (_regs)->pc = (_pc);                                    \
  93         (_regs)->ccr = 0x00;       /* clear kernel flag */      \
  94         (_regs)->exr = 0x78;       /* enable all interrupts */  \
  95         (_regs)->er5 = current->mm->start_data; /* GOT base */  \
  96         /* 14 = space for retaddr(4), vector(4), er0(4) and exr(2) on stack */ \
  97         wrusp(((unsigned long)(_usp)) - 14);                    \
  98 } while(0)
  99 #endif
 100
 101 /* Forward declaration, a strange C thing */
 102 struct task_struct;
 103
 104 /* Free all resources held by a thread. */
 105 static inline void release_thread(struct task_struct *dead_task)
 106 {
 107 }
 108
 109 /*
 110  * Free current thread data structures etc..
 111  */
 112 static inline void exit_thread(void)
 113 {
 114 }
 115
 116 /*
 117  * Return saved PC of a blocked thread.
 118  */
 119 unsigned long thread_saved_pc(struct task_struct *tsk);
 120 unsigned long get_wchan(struct task_struct *p);
 121
 122 #define KSTK_EIP(tsk)   \
 123     ({                  \
 124         unsigned long eip = 0;   \
 125         if ((tsk)->thread.esp0 > PAGE_SIZE && \
 126             MAP_NR((tsk)->thread.esp0) < max_mapnr) \
 127               eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
 128         eip; })
 129 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 130
 131 #define cpu_relax()    barrier()
 132 #define cpu_relax_lowlatency()  cpu_relax()
 133
 134 #define HARD_RESET_NOW() ({             \
 135         local_irq_disable();            \
 136         asm("jmp @@0");                 \
 137 })
 138
 139 #endif