Linux-2.6.12-rc2
[linux-flexiantxendom0-natty.git] / 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 <linux/config.h>
21 #include <asm/segment.h>
22 #include <asm/fpu.h>
23 #include <asm/ptrace.h>
24 #include <asm/current.h>
25
26 static inline unsigned long rdusp(void) {
27         extern unsigned int     sw_usp;
28         return(sw_usp);
29 }
30
31 static 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 /*
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
45  */
46 #define TASK_UNMAPPED_BASE      0
47
48 struct thread_struct {
49         unsigned long  ksp;             /* kernel stack pointer */
50         unsigned long  usp;             /* user stack pointer */
51         unsigned long  ccr;             /* saved status register */
52         unsigned long  esp0;            /* points to SR of stack frame */
53         struct {
54                 unsigned short *addr;
55                 unsigned short inst;
56         } breakinfo;
57 };
58
59 #define INIT_THREAD  {                                          \
60         .ksp  = sizeof(init_stack) + (unsigned long)init_stack, \
61         .usp  = 0,                                              \
62         .ccr  = PS_S,                                           \
63         .esp0 = 0,                                              \
64         .breakinfo = {                                          \
65                 .addr = (unsigned short *)-1,                   \
66                 .inst = 0                                       \
67         }                                                       \
68 }
69
70 /*
71  * Do necessary setup to start up a newly executed thread.
72  *
73  * pass the data segment into user programs if it exists,
74  * it can't hurt anything as far as I can tell
75  */
76 #if defined(__H8300H__)
77 #define start_thread(_regs, _pc, _usp)                          \
78 do {                                                            \
79         set_fs(USER_DS);           /* reads from user space */  \
80         (_regs)->pc = (_pc);                                    \
81         (_regs)->ccr &= 0x00;      /* clear kernel flag */      \
82         (_regs)->er5 = current->mm->start_data; /* GOT base */  \
83         wrusp((unsigned long)(_usp) - sizeof(unsigned long)*3); \
84 } while(0)
85 #endif
86 #if defined(__H8300S__)
87 #define start_thread(_regs, _pc, _usp)                          \
88 do {                                                            \
89         set_fs(USER_DS);           /* reads from user space */  \
90         (_regs)->pc = (_pc);                                    \
91         (_regs)->ccr = 0x00;       /* clear kernel flag */      \
92         (_regs)->exr = 0x78;       /* enable all interrupts */  \
93         (_regs)->er5 = current->mm->start_data; /* GOT base */  \
94         /* 14 = space for retaddr(4), vector(4), er0(4) and ext(2) on stack */ \
95         wrusp(((unsigned long)(_usp)) - 14);                    \
96 } while(0)
97 #endif
98
99 /* Forward declaration, a strange C thing */
100 struct task_struct;
101
102 /* Free all resources held by a thread. */
103 static inline void release_thread(struct task_struct *dead_task)
104 {
105 }
106
107 extern int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags);
108
109 #define prepare_to_copy(tsk)    do { } while (0)
110
111 /*
112  * Free current thread data structures etc..
113  */
114 static inline void exit_thread(void)
115 {
116 }
117
118 /*
119  * Return saved PC of a blocked thread.
120  */
121 unsigned long thread_saved_pc(struct task_struct *tsk);
122 unsigned long get_wchan(struct task_struct *p);
123
124 #define KSTK_EIP(tsk)   \
125     ({                  \
126         unsigned long eip = 0;   \
127         if ((tsk)->thread.esp0 > PAGE_SIZE && \
128             MAP_NR((tsk)->thread.esp0) < max_mapnr) \
129               eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
130         eip; })
131 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
132
133 #define cpu_relax()    do { } while (0)
134
135 #endif