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
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
|
/* Copyright (C) 1994, 1997 Free Software Foundation, Inc.
Contributed by Joel Sherrill (jsherril@redstone-emh2.army.mil),
On-Line Applications Research Corporation.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* i386.h
*
* This file contains macros which are used to access i80386
* registers which are not addressable by C. This file contains
* functions which are useful to those developing target
* specific support routines.
*/
#ifndef i386_h__
#define i386_h__
typedef unsigned char unsigned8;
typedef unsigned short unsigned16;
typedef unsigned int unsigned32;
#define disable_intr( isrlevel ) \
{ (isrlevel) = 0; \
asm volatile ( "pushf ; \
pop %0 ; \
cli " \
: "=r" ((isrlevel)) : "0" ((isrlevel)) ); \
}
#define enable_intr( isrlevel ) \
{ asm volatile ( "push %0 ; \
popf " \
: "=r" ((isrlevel)) : "0" ((isrlevel)) ); \
}
#define delay( _microseconds ) \
{ \
unsigned32 _counter; \
\
_counter = (_microseconds); \
\
asm volatile ( "0: nop;" \
" mov %0,%0 ;" \
" loop 0" : "=c" (_counter) \
: "0" (_counter) \
); \
\
}
/* segment access functions */
static inline unsigned16 get_cs()
{
register unsigned16 segment = 0;
asm volatile ( "movw %%cs,%0" : "=r" (segment) : "0" (segment) );
return segment;
}
static inline unsigned16 get_ds()
{
register unsigned16 segment = 0;
asm volatile ( "movw %%ds,%0" : "=r" (segment) : "0" (segment) );
return segment;
}
static inline unsigned16 get_es()
{
register unsigned16 segment = 0;
asm volatile ( "movw %%es,%0" : "=r" (segment) : "0" (segment) );
return segment;
}
static inline unsigned16 get_ss()
{
register unsigned16 segment = 0;
asm volatile ( "movw %%ss,%0" : "=r" (segment) : "0" (segment) );
return segment;
}
static inline unsigned16 get_fs()
{
register unsigned16 segment = 0;
asm volatile ( "movw %%fs,%0" : "=r" (segment) : "0" (segment) );
return segment;
}
static inline unsigned16 get_gs()
{
register unsigned16 segment = 0;
asm volatile ( "movw %%gs,%0" : "=r" (segment) : "0" (segment) );
return segment;
}
/* i80x86 I/O instructions */
#define outport_byte( _port, _value ) \
{ register unsigned16 __port = _port; \
register unsigned8 __value = _value; \
\
asm volatile ( "outb %0,%1" : "=a" (__value), "=d" (__port) \
: "0" (__value), "1" (__port) \
); \
}
#define outport_word( _port, _value ) \
{ register unsigned16 __port = _port; \
register unsigned16 __value = _value; \
\
asm volatile ( "outw %0,%1" : "=a" (__value), "=d" (__port) \
: "0" (__value), "1" (__port) \
); \
}
#define outport_long( _port, _value ) \
{ register unsigned16 __port = _port; \
register unsigned32 __value = _value; \
\
asm volatile ( "outl %0,%1" : "=a" (__value), "=d" (__port) \
: "0" (__value), "1" (__port) \
); \
}
#define inport_byte( _port, _value ) \
{ register unsigned16 __port = _port; \
register unsigned8 __value = 0; \
\
asm volatile ( "inb %1,%0" : "=a" (__value), "=d" (__port) \
: "0" (__value), "1" (__port) \
); \
_value = __value; \
}
#define inport_word( _port, _value ) \
{ register unsigned16 __port = _port; \
register unsigned16 __value = 0; \
\
asm volatile ( "inw %1,%0" : "=a" (__value), "=d" (__port) \
: "0" (__value), "1" (__port) \
); \
_value = __value; \
}
#define inport_long( _port, _value ) \
{ register unsigned16 __port = _port; \
register unsigned32 __value = 0; \
\
asm volatile ( "inl %1,%0" : "=a" (__value), "=d" (__port) \
: "0" (__value), "1" (__port) \
); \
_value = __value; \
}
/* structures */
/* See Chapter 5 - Memory Management in i386 manual */
struct GDT_slot {
unsigned16 limit_0_15;
unsigned16 base_0_15;
unsigned8 base_16_23;
unsigned8 type_dt_dpl_p;
unsigned8 limit_16_19_granularity;
unsigned8 base_24_31;
};
/* See Chapter 9 - Exceptions and Interrupts in i386 manual
*
* NOTE: This is the IDT entry for interrupt gates ONLY.
*/
struct IDT_slot {
unsigned16 offset_0_15;
unsigned16 segment_selector;
unsigned8 reserved;
unsigned8 p_dpl;
unsigned16 offset_16_31;
};
struct DTR_load_save_format {
unsigned16 limit;
unsigned32 physical_address;
};
/* variables */
extern struct IDT_slot Interrupt_descriptor_table[ 256 ];
extern struct GDT_slot Global_descriptor_table[ 8192 ];
/* functions */
#ifdef CPU_INITIALIZE
#define EXTERN
#else
#undef EXTERN
#define EXTERN extern
#endif
void *Logical_to_physical(
unsigned16 segment,
void *address
);
void *Physical_to_logical(
unsigned16 segment,
void *address
);
/* complicated static inline functions */
#define get_GDTR( _gdtr_address ) \
{ \
void *_gdtr = (_gdtr_address); \
\
asm volatile( "sgdt (%0)" : "=r" (_gdtr) : "0" (_gdtr) ); \
}
#define get_GDT_slot( _gdtr_base, _segment, _slot_address ) \
{ \
register unsigned32 _gdt_slot = (_gdtr_base) + (_segment); \
register volatile void *_slot = (_slot_address); \
register unsigned32 _temporary = 0; \
\
asm volatile( "movl %%gs:(%0),%1 ; \
movl %1,(%2) ; \
movl %%gs:4(%0),%1 ; \
movl %1,4(%2)" \
: "=r" (_gdt_slot), "=r" (_temporary), "=r" (_slot) \
: "0" (_gdt_slot), "1" (_temporary), "2" (_slot) \
); \
}
#define set_GDT_slot( _gdtr_base, _segment, _slot_address ) \
{ \
register unsigned32 _gdt_slot = (_gdtr_base) + (_segment); \
register volatile void *_slot = (_slot_address); \
register unsigned32 _temporary = 0; \
\
asm volatile( "movl (%2),%1 ; \
movl %1,%%gs:(%0) ; \
movl 4(%2),%1 ; \
movl %1,%%gs:4(%0) \
" \
: "=r" (_gdt_slot), "=r" (_temporary), "=r" (_slot) \
: "0" (_gdt_slot), "1" (_temporary), "2" (_slot) \
); \
}
static inline void set_segment(
unsigned16 segment,
unsigned32 base,
unsigned32 limit
)
{
struct DTR_load_save_format gdtr;
volatile struct GDT_slot Gdt_slot;
volatile struct GDT_slot *gdt_slot = &Gdt_slot;
unsigned16 tmp_segment = 0;
unsigned32 limit_adjusted;
/* load physical address of the GDT */
get_GDTR( &gdtr );
gdt_slot->type_dt_dpl_p = 0x92; /* present, dpl=0, */
/* application=1, */
/* type=data read/write */
gdt_slot->limit_16_19_granularity = 0x40; /* 32 bit segment */
limit_adjusted = limit;
if ( limit > 4095 ) {
gdt_slot->limit_16_19_granularity |= 0x80; /* set granularity bit */
limit_adjusted /= 4096;
}
gdt_slot->limit_16_19_granularity |= (limit_adjusted >> 16) & 0xff;
gdt_slot->limit_0_15 = limit_adjusted & 0xffff;
gdt_slot->base_0_15 = base & 0xffff;
gdt_slot->base_16_23 = (base >> 16) & 0xff;
gdt_slot->base_24_31 = (base >> 24);
set_GDT_slot( gdtr.physical_address, segment, gdt_slot );
/* Now, reload all segment registers so the limit takes effect. */
asm volatile( "movw %%ds,%0 ; movw %0,%%ds
movw %%es,%0 ; movw %0,%%es
movw %%fs,%0 ; movw %0,%%fs
movw %%gs,%0 ; movw %0,%%gs
movw %%ss,%0 ; movw %0,%%ss"
: "=r" (tmp_segment)
: "0" (tmp_segment)
);
}
#endif
/* end of include file */
|
