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
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
|
/////////////////////////////////////////////////////////////////////////
// $Id: segment_ctrl_pro.cc,v 1.11 2001/11/13 05:11:41 bdenney Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#define LOG_THIS BX_CPU_THIS_PTR
void
BX_CPU_C::load_seg_reg(bx_segment_reg_t *seg, Bit16u new_value)
{
#if BX_CPU_LEVEL >= 3
if (v8086_mode()) {
/* ??? don't need to set all these fields */
seg->selector.value = new_value;
seg->selector.rpl = 3;
seg->cache.valid = 1;
seg->cache.p = 1;
seg->cache.dpl = 3;
seg->cache.segment = 1; /* regular segment */
if (seg == &BX_CPU_THIS_PTR sregs[BX_SREG_CS])
seg->cache.u.segment.executable = 1; /* code segment */
else
seg->cache.u.segment.executable = 0; /* data segment */
seg->cache.u.segment.c_ed = 0; /* expand up */
seg->cache.u.segment.r_w = 1; /* writeable */
seg->cache.u.segment.a = 1; /* accessed */
seg->cache.u.segment.base = new_value << 4;
seg->cache.u.segment.limit = 0xffff;
seg->cache.u.segment.limit_scaled = 0xffff;
seg->cache.u.segment.g = 0; /* byte granular */
seg->cache.u.segment.d_b = 0; /* default 16bit size */
seg->cache.u.segment.avl = 0;
return;
}
#endif
#if BX_CPU_LEVEL >= 2
if (protected_mode()) {
if (seg == &BX_CPU_THIS_PTR sregs[BX_SREG_SS]) {
Bit16u index;
Bit8u ti;
Bit8u rpl;
bx_descriptor_t descriptor;
Bit32u dword1, dword2;
if ((new_value & 0xfffc) == 0) { /* null selector */
BX_PANIC(("load_seg_reg: SS: new_value == 0"));
exception(BX_GP_EXCEPTION, 0, 0);
return;
}
index = new_value >> 3;
ti = (new_value >> 2) & 0x01;
rpl = (new_value & 0x03);
/* examine AR byte of destination selector for legal values: */
if (ti == 0) { /* GDT */
if ((index*8 + 7) > BX_CPU_THIS_PTR gdtr.limit) {
BX_PANIC(("load_seg_reg: GDT: %s: index(%04x*8+7) > limit(%06x)",
BX_CPU_THIS_PTR strseg(seg), (unsigned) index, (unsigned) BX_CPU_THIS_PTR gdtr.limit));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
access_linear(BX_CPU_THIS_PTR gdtr.base + index*8, 4, 0,
BX_READ, &dword1);
access_linear(BX_CPU_THIS_PTR gdtr.base + index*8 + 4, 4, 0,
BX_READ, &dword2);
}
else { /* LDT */
if (BX_CPU_THIS_PTR ldtr.cache.valid==0) { /* ??? */
BX_ERROR(("load_seg_reg: LDT invalid"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
if ((index*8 + 7) > BX_CPU_THIS_PTR ldtr.cache.u.ldt.limit) {
BX_ERROR(("load_seg_reg ss: LDT: index > limit"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + index*8, 4, 0,
BX_READ, &dword1);
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + index*8 + 4, 4, 0,
BX_READ, &dword2);
}
/* selector's RPL must = CPL, else #GP(selector) */
if (rpl != CPL) {
BX_ERROR(("load_seg_reg(): rpl != CPL"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
parse_descriptor(dword1, dword2, &descriptor);
if (descriptor.valid==0) {
BX_ERROR(("load_seg_reg(): valid bit cleared"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
/* AR byte must indicate a writable data segment else #GP(selector) */
if ( (descriptor.segment==0) ||
descriptor.u.segment.executable ||
descriptor.u.segment.r_w==0 ) {
BX_ERROR(("load_seg_reg(): not writable data segment"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
}
/* DPL in the AR byte must equal CPL else #GP(selector) */
if (descriptor.dpl != CPL) {
BX_ERROR(("load_seg_reg(): dpl != CPL"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
}
/* segment must be marked PRESENT else #SS(selector) */
if (descriptor.p == 0) {
BX_ERROR(("load_seg_reg(): not present"));
exception(BX_SS_EXCEPTION, new_value & 0xfffc, 0);
}
/* load SS with selector, load SS cache with descriptor */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value = new_value;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.index = index;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.ti = ti;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.rpl = rpl;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache = descriptor;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.valid = 1;
/* now set accessed bit in descriptor */
dword2 |= 0x0100;
if (ti == 0) { /* GDT */
access_linear(BX_CPU_THIS_PTR gdtr.base + index*8 + 4, 4, 0,
BX_WRITE, &dword2);
}
else { /* LDT */
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + index*8 + 4, 4, 0,
BX_WRITE, &dword2);
}
return;
}
else if ( (seg==&BX_CPU_THIS_PTR sregs[BX_SREG_DS]) ||
(seg==&BX_CPU_THIS_PTR sregs[BX_SREG_ES])
#if BX_CPU_LEVEL >= 3
|| (seg==&BX_CPU_THIS_PTR sregs[BX_SREG_FS]) ||
(seg==&BX_CPU_THIS_PTR sregs[BX_SREG_GS])
#endif
) {
Bit16u index;
Bit8u ti;
Bit8u rpl;
bx_descriptor_t descriptor;
Bit32u dword1, dword2;
if ((new_value & 0xfffc) == 0) { /* null selector */
seg->selector.index = 0;
seg->selector.ti = 0;
seg->selector.rpl = 0;
seg->selector.value = 0;
seg->cache.valid = 0; /* invalidate null selector */
return;
}
index = new_value >> 3;
ti = (new_value >> 2) & 0x01;
rpl = (new_value & 0x03);
/* selector index must be within descriptor limits, else #GP(selector) */
if (ti == 0) { /* GDT */
if ((index*8 + 7) > BX_CPU_THIS_PTR gdtr.limit) {
BX_ERROR(("load_seg_reg: GDT: %s: index(%04x) > limit(%06x)",
BX_CPU_THIS_PTR strseg(seg), (unsigned) index, (unsigned) BX_CPU_THIS_PTR gdtr.limit));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
access_linear(BX_CPU_THIS_PTR gdtr.base + index*8, 4, 0,
BX_READ, &dword1);
access_linear(BX_CPU_THIS_PTR gdtr.base + index*8 + 4, 4, 0,
BX_READ, &dword2);
}
else { /* LDT */
if (BX_CPU_THIS_PTR ldtr.cache.valid==0) {
BX_ERROR(("load_seg_reg: LDT invalid"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
if ((index*8 + 7) > BX_CPU_THIS_PTR ldtr.cache.u.ldt.limit) {
BX_ERROR(("load_seg_reg ds,es: LDT: index > limit"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + index*8, 4, 0,
BX_READ, &dword1);
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + index*8 + 4, 4, 0,
BX_READ, &dword2);
}
parse_descriptor(dword1, dword2, &descriptor);
if (descriptor.valid==0) {
BX_ERROR(("load_seg_reg(): valid bit cleared"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
/* AR byte must indicate data or readable code segment else #GP(selector) */
if ( descriptor.segment==0 ||
(descriptor.u.segment.executable==1 &&
descriptor.u.segment.r_w==0) ) {
BX_ERROR(("load_seg_reg(): not data or readable code"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
/* If data or non-conforming code, then both the RPL and the CPL
* must be less than or equal to DPL in AR byte else #GP(selector) */
if ( descriptor.u.segment.executable==0 ||
descriptor.u.segment.c_ed==0 ) {
if ((rpl > descriptor.dpl) || (CPL > descriptor.dpl)) {
BX_ERROR(("load_seg_reg: RPL & CPL must be <= DPL"));
exception(BX_GP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
}
/* segment must be marked PRESENT else #NP(selector) */
if (descriptor.p == 0) {
BX_ERROR(("load_seg_reg: segment not present"));
exception(BX_NP_EXCEPTION, new_value & 0xfffc, 0);
return;
}
/* load segment register with selector */
/* load segment register-cache with descriptor */
seg->selector.value = new_value;
seg->selector.index = index;
seg->selector.ti = ti;
seg->selector.rpl = rpl;
seg->cache = descriptor;
seg->cache.valid = 1;
/* now set accessed bit in descriptor */
/* wmr: don't bother if it's already set (thus allowing */
/* GDT to be in read-only pages like real hdwe does) */
if (!(dword2 & 0x0100)) {
dword2 |= 0x0100;
if (ti == 0) { /* GDT */
access_linear(BX_CPU_THIS_PTR gdtr.base + index*8 + 4, 4, 0,
BX_WRITE, &dword2);
}
else { /* LDT */
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + index*8 + 4, 4, 0,
BX_WRITE, &dword2);
}
}
return;
}
else {
BX_PANIC(("load_seg_reg(): invalid segment register passed!"));
return;
}
}
/* real mode */
/* seg->limit = ; ??? different behaviours depening on seg reg. */
/* something about honoring previous values */
/* ??? */
if (seg == &BX_CPU_THIS_PTR sregs[BX_SREG_CS]) {
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value = new_value;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.valid = 1;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.p = 1;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.dpl = 0;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.segment = 1; /* regular segment */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.executable = 1; /* code segment */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.c_ed = 0; /* expand up */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.r_w = 1; /* writeable */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.a = 1; /* accessed */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.base = new_value << 4;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit = 0xffff;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.limit_scaled = 0xffff;
#if BX_CPU_LEVEL >= 3
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.g = 0; /* byte granular */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.d_b = 0; /* default 16bit size */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.u.segment.avl = 0;
#endif
}
else { /* SS, DS, ES, FS, GS */
seg->selector.value = new_value;
seg->cache.valid = 1;
seg->cache.p = 1; // set this???
seg->cache.u.segment.base = new_value << 4;
seg->cache.segment = 1; /* regular segment */
seg->cache.u.segment.a = 1; /* accessed */
/* set G, D_B, AVL bits here ??? */
}
#else /* 8086 */
seg->selector.value = new_value;
seg->cache.u.segment.base = new_value << 4;
#endif
}
#if BX_CPU_LEVEL >= 2
void
BX_CPU_C::parse_selector(Bit16u raw_selector, bx_selector_t *selector)
{
selector->value = raw_selector;
selector->index = raw_selector >> 3;
selector->ti = (raw_selector >> 2) & 0x01;
selector->rpl = raw_selector & 0x03;
}
#endif
void
BX_CPU_C::parse_descriptor(Bit32u dword1, Bit32u dword2, bx_descriptor_t *temp)
{
Bit8u AR_byte;
AR_byte = dword2 >> 8;
temp->p = (AR_byte >> 7) & 0x01;
temp->dpl = (AR_byte >> 5) & 0x03;
temp->segment = (AR_byte >> 4) & 0x01;
temp->type = (AR_byte & 0x0f);
temp->valid = 0; /* start out invalid */
if (temp->segment) { /* data/code segment descriptors */
temp->u.segment.executable = (AR_byte >> 3) & 0x01;
temp->u.segment.c_ed = (AR_byte >> 2) & 0x01;
temp->u.segment.r_w = (AR_byte >> 1) & 0x01;
temp->u.segment.a = (AR_byte >> 0) & 0x01;
temp->u.segment.limit = (dword1 & 0xffff);
temp->u.segment.base = (dword1 >> 16) |
((dword2 & 0xFF) << 16);
#if BX_CPU_LEVEL >= 3
temp->u.segment.limit |= (dword2 & 0x000F0000);
temp->u.segment.g = (dword2 & 0x00800000) > 0;
temp->u.segment.d_b = (dword2 & 0x00400000) > 0;
temp->u.segment.avl = (dword2 & 0x00100000) > 0;
temp->u.segment.base |= (dword2 & 0xFF000000);
if (temp->u.segment.g) {
if ( (temp->u.segment.executable==0) && (temp->u.segment.c_ed) )
temp->u.segment.limit_scaled = (temp->u.segment.limit << 12);
else
temp->u.segment.limit_scaled = (temp->u.segment.limit << 12) | 0x0fff;
}
else
#endif
temp->u.segment.limit_scaled = temp->u.segment.limit;
temp->valid = 1;
}
else { // system & gate segment descriptors
switch ( temp->type ) {
case 0: // reserved
case 8: // reserved
case 10: // reserved
case 13: // reserved
temp->valid = 0;
break;
case 1: // 286 TSS (available)
case 3: // 286 TSS (busy)
temp->u.tss286.base = (dword1 >> 16) |
((dword2 & 0xff) << 16);
temp->u.tss286.limit = (dword1 & 0xffff);
temp->valid = 1;
break;
case 2: // LDT descriptor
temp->u.ldt.base = (dword1 >> 16) |
((dword2 & 0xFF) << 16);
#if BX_CPU_LEVEL >= 3
temp->u.ldt.base |= (dword2 & 0xff000000);
#endif
temp->u.ldt.limit = (dword1 & 0xffff);
temp->valid = 1;
break;
case 4: // 286 call gate
case 6: // 286 interrupt gate
case 7: // 286 trap gate
/* word count only used for call gate */
temp->u.gate286.word_count = dword2 & 0x1f;
temp->u.gate286.dest_selector = dword1 >> 16;;
temp->u.gate286.dest_offset = dword1 & 0xffff;
temp->valid = 1;
break;
case 5: // 286/386 task gate
temp->u.taskgate.tss_selector = dword1 >> 16;;
temp->valid = 1;
break;
#if BX_CPU_LEVEL >= 3
case 9: // 386 TSS (available)
case 11: // 386 TSS (busy)
temp->u.tss386.base = (dword1 >> 16) |
((dword2 & 0xff) << 16) |
(dword2 & 0xff000000);
temp->u.tss386.limit = (dword1 & 0x0000ffff) |
(dword2 & 0x000f0000);
temp->u.tss386.g = (dword2 & 0x00800000) > 0;
temp->u.tss386.avl = (dword2 & 0x00100000) > 0;
if (temp->u.tss386.g)
temp->u.tss386.limit_scaled = (temp->u.tss386.limit << 12) | 0x0fff;
else
temp->u.tss386.limit_scaled = temp->u.tss386.limit;
temp->valid = 1;
break;
case 12: // 386 call gate
case 14: // 386 interrupt gate
case 15: // 386 trap gate
// word count only used for call gate
temp->u.gate386.dword_count = dword2 & 0x1f;
temp->u.gate386.dest_selector = dword1 >> 16;;
temp->u.gate386.dest_offset = (dword2 & 0xffff0000) |
(dword1 & 0x0000ffff);
temp->valid = 1;
break;
#endif
default: BX_PANIC(("parse_descriptor(): case %d unfinished",
(unsigned) temp->type));
temp->valid = 0;
}
}
}
void
BX_CPU_C::load_ldtr(bx_selector_t *selector, bx_descriptor_t *descriptor)
{
/* check for null selector, if so invalidate LDTR */
if ( (selector->value & 0xfffc)==0 ) {
BX_CPU_THIS_PTR ldtr.selector = *selector;
BX_CPU_THIS_PTR ldtr.cache.valid = 0;
return;
}
if (!descriptor)
BX_PANIC(("load_ldtr(): descriptor == NULL!"));
BX_CPU_THIS_PTR ldtr.cache = *descriptor; /* whole structure copy */
BX_CPU_THIS_PTR ldtr.selector = *selector;
if (BX_CPU_THIS_PTR ldtr.cache.u.ldt.limit < 7) {
BX_PANIC(("load_ldtr(): ldtr.limit < 7"));
}
BX_CPU_THIS_PTR ldtr.cache.valid = 1;
}
void
BX_CPU_C::load_cs(bx_selector_t *selector, bx_descriptor_t *descriptor,
Bit8u cpl)
{
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector = *selector;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache = *descriptor;
/* caller may request different CPL then in selector */
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.rpl = cpl;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].cache.valid = 1; /* ??? */
// (BW) Added cpl to the selector value.
BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value =
(0xfffc & BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS].selector.value) | cpl;
}
void
BX_CPU_C::load_ss(bx_selector_t *selector, bx_descriptor_t *descriptor, Bit8u cpl)
{
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector = *selector;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache = *descriptor;
BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.rpl = cpl;
if ( (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].selector.value & 0xfffc) == 0 )
BX_PANIC(("load_ss(): null selector passed"));
if ( !BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.valid ) {
BX_PANIC(("load_ss(): invalid selector/descriptor passed."));
}
}
#if BX_CPU_LEVEL >= 2
void
BX_CPU_C::fetch_raw_descriptor(bx_selector_t *selector,
Bit32u *dword1, Bit32u *dword2, Bit8u exception_no)
{
if (selector->ti == 0) { /* GDT */
if ((selector->index*8 + 7) > BX_CPU_THIS_PTR gdtr.limit) {
BX_INFO(("-----------------------------------"));
BX_INFO(("selector->index*8 + 7 = %u", (unsigned) selector->index*8 + 7));
BX_INFO(("gdtr.limit = %u", (unsigned) BX_CPU_THIS_PTR gdtr.limit));
BX_INFO(("fetch_raw_descriptor: GDT: index > limit"));
debug(BX_CPU_THIS_PTR prev_eip);
BX_INFO(("-----------------------------------"));
exception(exception_no, selector->value & 0xfffc, 0);
return;
}
access_linear(BX_CPU_THIS_PTR gdtr.base + selector->index*8, 4, 0,
BX_READ, dword1);
access_linear(BX_CPU_THIS_PTR gdtr.base + selector->index*8 + 4, 4, 0,
BX_READ, dword2);
}
else { /* LDT */
if (BX_CPU_THIS_PTR ldtr.cache.valid==0) {
BX_PANIC(("fetch_raw_descriptor: LDTR.valid=0"));
}
if ((selector->index*8 + 7) > BX_CPU_THIS_PTR ldtr.cache.u.ldt.limit) {
BX_PANIC(("fetch_raw_descriptor: LDT: index > limit"));
exception(exception_no, selector->value & 0xfffc, 0);
return;
}
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + selector->index*8, 4, 0,
BX_READ, dword1);
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + selector->index*8 + 4, 4, 0,
BX_READ, dword2);
}
}
#endif
Boolean
BX_CPU_C::fetch_raw_descriptor2(bx_selector_t *selector,
Bit32u *dword1, Bit32u *dword2)
{
if (selector->ti == 0) { /* GDT */
if ((selector->index*8 + 7) > BX_CPU_THIS_PTR gdtr.limit)
return(0);
access_linear(BX_CPU_THIS_PTR gdtr.base + selector->index*8, 4, 0,
BX_READ, dword1);
access_linear(BX_CPU_THIS_PTR gdtr.base + selector->index*8 + 4, 4, 0,
BX_READ, dword2);
return(1);
}
else { /* LDT */
if ((selector->index*8 + 7) > BX_CPU_THIS_PTR ldtr.cache.u.ldt.limit)
return(0);
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + selector->index*8, 4, 0,
BX_READ, dword1);
access_linear(BX_CPU_THIS_PTR ldtr.cache.u.ldt.base + selector->index*8 + 4, 4, 0,
BX_READ, dword2);
return(1);
}
}
|
