1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
// Code to access multiple segments within gcc.
//
// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#ifndef __FARPTR_H
#define __FARPTR_H
#include "ioport.h" // insb
// Low level macros for reading/writing memory via a segment selector.
#define READ8_SEG(SEG, var) ({ \
u8 __value; \
__asm__ __volatile__("movb %%" #SEG ":%1, %b0" \
: "=Qi"(__value) : "m"(var)); \
__value; })
#define READ16_SEG(SEG, var) ({ \
u16 __value; \
__asm__ __volatile__("movw %%" #SEG ":%1, %w0" \
: "=ri"(__value) : "m"(var)); \
__value; })
#define READ32_SEG(SEG, var) ({ \
u32 __value; \
__asm__ __volatile__("movl %%" #SEG ":%1, %0" \
: "=ri"(__value) : "m"(var)); \
__value; })
#define WRITE8_SEG(SEG, var, value) \
__asm__ __volatile__("movb %b0, %%" #SEG ":%1" \
: : "Q"(value), "m"(var))
#define WRITE16_SEG(SEG, var, value) \
__asm__ __volatile__("movw %w0, %%" #SEG ":%1" \
: : "r"(value), "m"(var))
#define WRITE32_SEG(SEG, var, value) \
__asm__ __volatile__("movl %0, %%" #SEG ":%1" \
: : "r"(value), "m"(var))
// Low level macros for getting/setting a segment register.
#define __SET_SEG(SEG, value) \
__asm__ __volatile__("movw %w0, %%" #SEG : : "r"(value))
#define __GET_SEG(SEG) ({ \
u16 __seg; \
__asm__ __volatile__("movw %%" #SEG ", %w0" : "=r"(__seg)); \
__seg;})
// Macros for automatically choosing the appropriate memory size
// access method.
extern void __force_link_error__unknown_type();
#define __GET_VAR(seg, var) ({ \
typeof(var) __val; \
if (__builtin_types_compatible_p(typeof(__val), u8)) \
__val = READ8_SEG(seg, var); \
else if (__builtin_types_compatible_p(typeof(__val), u16)) \
__val = READ16_SEG(seg, var); \
else if (__builtin_types_compatible_p(typeof(__val), u32)) \
__val = READ32_SEG(seg, var); \
else \
__force_link_error__unknown_type(); \
__val; })
#define __SET_VAR(seg, var, val) do { \
if (__builtin_types_compatible_p(typeof(var), u8)) \
WRITE8_SEG(seg, var, (val)); \
else if (__builtin_types_compatible_p(typeof(var), u16)) \
WRITE16_SEG(seg, var, (val)); \
else if (__builtin_types_compatible_p(typeof(var), u32)) \
WRITE32_SEG(seg, var, (val)); \
else \
__force_link_error__unknown_type(); \
} while (0)
// Macros for accessing a variable in another segment. (They
// automatically update the %es segment and then make the appropriate
// access.)
#define __GET_FARVAR(seg, var) ({ \
SET_SEG(ES, (seg)); \
GET_VAR(ES, (var)); })
#define __SET_FARVAR(seg, var, val) do { \
typeof(var) __sfv_val = (val); \
SET_SEG(ES, (seg)); \
SET_VAR(ES, (var), __sfv_val); \
} while (0)
// Macros for accesssing a 32bit pointer from 16bit mode. (They
// automatically update the %es segment, break the pointer into
// segment/offset, and then make the access.)
#define __GET_FARPTR(ptr) ({ \
typeof(&(ptr)) __ptr = &(ptr); \
GET_FARVAR(FARPTR_TO_SEG(__ptr) \
, *(typeof(__ptr))FARPTR_TO_OFFSET(__ptr)); })
#define __SET_FARPTR(ptr, val) do { \
typeof (&(ptr)) __ptr = &(ptr); \
SET_FARVAR(FARPTR_TO_SEG(__ptr) \
, *(typeof(__ptr))FARPTR_TO_OFFSET(__ptr) \
, (val)); \
} while (0)
// Macros for converting to/from 32bit style pointers to their
// equivalent 16bit segment/offset values.
#define FARPTR_TO_SEG(p) (((u32)(p)) >> 4)
#define FARPTR_TO_OFFSET(p) (((u32)(p)) & 0xf)
#define MAKE_FARPTR(seg,off) ((void*)(((seg)<<4)+(off)))
#ifdef MODE16
// Definitions when in 16 bit mode.
#define GET_FARVAR(seg, var) __GET_FARVAR((seg), (var))
#define SET_FARVAR(seg, var, val) __SET_FARVAR((seg), (var), (val))
#define GET_VAR(seg, var) __GET_VAR(seg, (var))
#define SET_VAR(seg, var, val) __SET_VAR(seg, (var), (val))
#define SET_SEG(SEG, value) __SET_SEG(SEG, (value))
#define GET_SEG(SEG) __GET_SEG(SEG)
#define GET_FARPTR(ptr) __GET_FARPTR(ptr)
#define SET_FARPTR(ptr, val) __SET_FARPTR((ptr), (val))
static inline void insb_far(u16 port, void *farptr, u16 count) {
SET_SEG(ES, FARPTR_TO_SEG(farptr));
insb(port, (u8*)FARPTR_TO_OFFSET(farptr), count);
}
static inline void insw_far(u16 port, void *farptr, u16 count) {
SET_SEG(ES, FARPTR_TO_SEG(farptr));
insw(port, (u16*)FARPTR_TO_OFFSET(farptr), count);
}
static inline void insl_far(u16 port, void *farptr, u16 count) {
SET_SEG(ES, FARPTR_TO_SEG(farptr));
insl(port, (u32*)FARPTR_TO_OFFSET(farptr), count);
}
static inline void outsb_far(u16 port, void *farptr, u16 count) {
SET_SEG(ES, FARPTR_TO_SEG(farptr));
outsb(port, (u8*)FARPTR_TO_OFFSET(farptr), count);
}
static inline void outsw_far(u16 port, void *farptr, u16 count) {
SET_SEG(ES, FARPTR_TO_SEG(farptr));
outsw(port, (u16*)FARPTR_TO_OFFSET(farptr), count);
}
static inline void outsl_far(u16 port, void *farptr, u16 count) {
SET_SEG(ES, FARPTR_TO_SEG(farptr));
outsl(port, (u32*)FARPTR_TO_OFFSET(farptr), count);
}
#else
// In 32-bit mode there is no need to mess with the segments.
#define GET_FARVAR(seg, var) \
(*((typeof(&(var)))MAKE_FARPTR((seg), (u32)&(var))))
#define SET_FARVAR(seg, var, val) \
do { GET_FARVAR((seg), (var)) = (val); } while (0)
#define GET_VAR(seg, var) (var)
#define SET_VAR(seg, var, val) do { (var) = (val); } while (0)
#define SET_SEG(SEG, value) ((void)(value))
#define GET_SEG(SEG) 0
#define GET_FARPTR(ptr) (ptr)
#define SET_FARPTR(ptr, val) do { (ptr) = (val); } while (0)
#define insb_far(port, farptr, count) insb(port, farptr, count)
#define insw_far(port, farptr, count) insw(port, farptr, count)
#define insl_far(port, farptr, count) insl(port, farptr, count)
#define outsb_far(port, farptr, count) outsb(port, farptr, count)
#define outsw_far(port, farptr, count) outsw(port, farptr, count)
#define outsl_far(port, farptr, count) outsl(port, farptr, count)
#endif
#endif // farptr.h
|
