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Linux kernel mirror (for testing)
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linux
1/*
2 * include/asm-m68k/processor.h
3 *
4 * Copyright (C) 1995 Hamish Macdonald
5 */
6
7#ifndef __ASM_M68K_PROCESSOR_H
8#define __ASM_M68K_PROCESSOR_H
9
10/*
11 * Default implementation of macro that returns current
12 * instruction pointer ("program counter").
13 */
14#define current_text_addr() ({ __label__ _l; _l: &&_l;})
15
16#include <linux/config.h>
17#include <linux/threads.h>
18#include <asm/types.h>
19#include <asm/segment.h>
20#include <asm/fpu.h>
21#include <asm/ptrace.h>
22#include <asm/current.h>
23
24static inline unsigned long rdusp(void)
25{
26#ifdef CONFIG_COLDFIRE
27 extern unsigned int sw_usp;
28 return(sw_usp);
29#else
30 unsigned long usp;
31 __asm__ __volatile__("move %/usp,%0" : "=a" (usp));
32 return usp;
33#endif
34}
35
36static inline void wrusp(unsigned long usp)
37{
38#ifdef CONFIG_COLDFIRE
39 extern unsigned int sw_usp;
40 sw_usp = usp;
41#else
42 __asm__ __volatile__("move %0,%/usp" : : "a" (usp));
43#endif
44}
45
46/*
47 * User space process size: 3.75GB. This is hardcoded into a few places,
48 * so don't change it unless you know what you are doing.
49 */
50#define TASK_SIZE (0xF0000000UL)
51
52/*
53 * This decides where the kernel will search for a free chunk of vm
54 * space during mmap's. We won't be using it
55 */
56#define TASK_UNMAPPED_BASE 0
57
58/*
59 * if you change this structure, you must change the code and offsets
60 * in m68k/machasm.S
61 */
62
63struct thread_struct {
64 unsigned long ksp; /* kernel stack pointer */
65 unsigned long usp; /* user stack pointer */
66 unsigned short sr; /* saved status register */
67 unsigned short fs; /* saved fs (sfc, dfc) */
68 unsigned long crp[2]; /* cpu root pointer */
69 unsigned long esp0; /* points to SR of stack frame */
70 unsigned long fp[8*3];
71 unsigned long fpcntl[3]; /* fp control regs */
72 unsigned char fpstate[FPSTATESIZE]; /* floating point state */
73};
74
75#define INIT_THREAD { \
76 sizeof(init_stack) + (unsigned long) init_stack, 0, \
77 PS_S, __KERNEL_DS, \
78 {0, 0}, 0, {0,}, {0, 0, 0}, {0,}, \
79}
80
81/*
82 * Do necessary setup to start up a newly executed thread.
83 *
84 * pass the data segment into user programs if it exists,
85 * it can't hurt anything as far as I can tell
86 */
87#define start_thread(_regs, _pc, _usp) \
88do { \
89 set_fs(USER_DS); /* reads from user space */ \
90 (_regs)->pc = (_pc); \
91 if (current->mm) \
92 (_regs)->d5 = current->mm->start_data; \
93 (_regs)->sr &= ~0x2000; \
94 wrusp(_usp); \
95} while(0)
96
97/* Forward declaration, a strange C thing */
98struct task_struct;
99
100/* Free all resources held by a thread. */
101static inline void release_thread(struct task_struct *dead_task)
102{
103}
104
105/* Prepare to copy thread state - unlazy all lazy status */
106#define prepare_to_copy(tsk) do { } while (0)
107
108extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
109
110/*
111 * Free current thread data structures etc..
112 */
113static inline void exit_thread(void)
114{
115}
116
117unsigned long thread_saved_pc(struct task_struct *tsk);
118unsigned long get_wchan(struct task_struct *p);
119
120#define KSTK_EIP(tsk) \
121 ({ \
122 unsigned long eip = 0; \
123 if ((tsk)->thread.esp0 > PAGE_SIZE && \
124 (virt_addr_valid((tsk)->thread.esp0))) \
125 eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
126 eip; })
127#define KSTK_ESP(tsk) ((tsk) == current ? rdusp() : (tsk)->thread.usp)
128
129#define cpu_relax() do { } while (0)
130
131#endif