2 * include/asm-h8300/processor.h
4 * Copyright (C) 2002 Yoshinori Sato
6 * Based on: linux/asm-m68nommu/processor.h
8 * Copyright (C) 1995 Hamish Macdonald
11 #ifndef __ASM_H8300_PROCESSOR_H
12 #define __ASM_H8300_PROCESSOR_H
15 * Default implementation of macro that returns current
16 * instruction pointer ("program counter").
18 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
20 #include <linux/config.h>
21 #include <asm/segment.h>
23 #include <asm/ptrace.h>
24 #include <asm/current.h>
26 extern inline unsigned long rdusp(void) {
27 extern unsigned int sw_usp;
31 extern inline void wrusp(unsigned long usp) {
32 extern unsigned int sw_usp;
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.
40 #define TASK_SIZE (0xFFFFFFFFUL)
43 * This decides where the kernel will search for a free chunk of vm
44 * space during mmap's. We won't be using it
46 #define TASK_UNMAPPED_BASE 0
53 struct 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 */
64 #define INIT_THREAD { \
65 sizeof(init_stack) + (unsigned long) init_stack, 0, \
66 PS_S, 0, {(unsigned short *)-1, 0}, \
70 * Do necessary setup to start up a newly executed thread.
72 * pass the data segment into user programs if it exists,
73 * it can't hurt anything as far as I can tell
75 #if defined(__H8300H__)
76 #define start_thread(_regs, _pc, _usp) \
78 set_fs(USER_DS); /* reads from user space */ \
79 (_regs)->pc = (_pc); \
80 (_regs)->ccr &= 0x00; /* clear kernel flag */ \
81 wrusp((unsigned long)(_usp) - sizeof(unsigned long)*3); \
84 #if defined(__H8300S__)
85 #define start_thread(_regs, _pc, _usp) \
87 set_fs(USER_DS); /* reads from user space */ \
88 (_regs)->pc = (_pc); \
89 (_regs)->ccr = 0x00; /* clear kernel flag */ \
90 (_regs)->exr = 0x78; /* enable all interrupts */ \
91 /* 14 = space for retaddr(4), vector(4), er0(4) and ext(2) on stack */ \
92 wrusp(((unsigned long)(_usp)) - 14); \
96 /* Forward declaration, a strange C thing */
99 /* Free all resources held by a thread. */
100 static inline void release_thread(struct task_struct *dead_task)
104 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
106 #define prepare_to_copy(tsk) do { } while (0)
109 * Free current thread data structures etc..
111 static inline void exit_thread(void)
116 * Return saved PC of a blocked thread.
118 unsigned long thread_saved_pc(struct task_struct *tsk);
119 unsigned long get_wchan(struct task_struct *p);
121 #define KSTK_EIP(tsk) \
123 unsigned long eip = 0; \
124 if ((tsk)->thread.esp0 > PAGE_SIZE && \
125 MAP_NR((tsk)->thread.esp0) < max_mapnr) \
126 eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
128 #define KSTK_ESP(tsk) ((tsk) == current ? rdusp() : (tsk)->thread.usp)
130 #define cpu_relax() do { } while (0)