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