src/gba/io.c (view raw)
1/* Copyright (c) 2013-2015 Jeffrey Pfau
2 *
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6#include "io.h"
7
8#include "gba/supervisor/rr.h"
9#include "gba/serialize.h"
10#include "gba/sio.h"
11#include "gba/video.h"
12
13const char* GBAIORegisterNames[] = {
14 // Video
15 "DISPCNT",
16 0,
17 "DISPSTAT",
18 "VCOUNT",
19 "BG0CNT",
20 "BG1CNT",
21 "BG2CNT",
22 "BG3CNT",
23 "BG0HOFS",
24 "BG0VOFS",
25 "BG1HOFS",
26 "BG1VOFS",
27 "BG2HOFS",
28 "BG2VOFS",
29 "BG3HOFS",
30 "BG3VOFS",
31 "BG2PA",
32 "BG2PB",
33 "BG2PC",
34 "BG2PD",
35 "BG2X_LO",
36 "BG2X_HI",
37 "BG2Y_LO",
38 "BG2Y_HI",
39 "BG3PA",
40 "BG3PB",
41 "BG3PC",
42 "BG3PD",
43 "BG3X_LO",
44 "BG3X_HI",
45 "BG3Y_LO",
46 "BG3Y_HI",
47 "WIN0H",
48 "WIN1H",
49 "WIN0V",
50 "WIN1V",
51 "WININ",
52 "WINOUT",
53 "MOSAIC",
54 0,
55 "BLDCNT",
56 "BLDALPHA",
57 "BLDY",
58 0,
59 0,
60 0,
61 0,
62 0,
63
64 // Sound
65 "SOUND1CNT_LO",
66 "SOUND1CNT_HI",
67 "SOUND1CNT_X",
68 0,
69 "SOUND2CNT_LO",
70 0,
71 "SOUND2CNT_HI",
72 0,
73 "SOUND3CNT_LO",
74 "SOUND3CNT_HI",
75 "SOUND3CNT_X",
76 0,
77 "SOUND4CNT_LO",
78 0,
79 "SOUND4CNT_HI",
80 0,
81 "SOUNDCNT_LO",
82 "SOUNDCNT_HI",
83 "SOUNDCNT_X",
84 0,
85 "SOUNDBIAS",
86 0,
87 0,
88 0,
89 "WAVE_RAM0_LO",
90 "WAVE_RAM0_HI",
91 "WAVE_RAM1_LO",
92 "WAVE_RAM1_HI",
93 "WAVE_RAM2_LO",
94 "WAVE_RAM2_HI",
95 "WAVE_RAM3_LO",
96 "WAVE_RAM3_HI",
97 "FIFO_A_LO",
98 "FIFO_A_HI",
99 "FIFO_B_LO",
100 "FIFO_B_HI",
101 0,
102 0,
103 0,
104 0,
105
106 // DMA
107 "DMA0SAD_LO",
108 "DMA0SAD_HI",
109 "DMA0DAD_LO",
110 "DMA0DAD_HI",
111 "DMA0CNT_LO",
112 "DMA0CNT_HI",
113 "DMA1SAD_LO",
114 "DMA1SAD_HI",
115 "DMA1DAD_LO",
116 "DMA1DAD_HI",
117 "DMA1CNT_LO",
118 "DMA1CNT_HI",
119 "DMA2SAD_LO",
120 "DMA2SAD_HI",
121 "DMA2DAD_LO",
122 "DMA2DAD_HI",
123 "DMA2CNT_LO",
124 "DMA2CNT_HI",
125 "DMA3SAD_LO",
126 "DMA3SAD_HI",
127 "DMA3DAD_LO",
128 "DMA3DAD_HI",
129 "DMA3CNT_LO",
130 "DMA3CNT_HI",
131
132 0, 0, 0, 0, 0, 0, 0, 0,
133 0, 0, 0, 0, 0, 0, 0, 0,
134
135 // Timers
136 "TM0CNT_LO",
137 "TM0CNT_HI",
138 "TM1CNT_LO",
139 "TM1CNT_HI",
140 "TM2CNT_LO",
141 "TM2CNT_HI",
142 "TM3CNT_LO",
143 "TM3CNT_HI",
144
145 0, 0, 0, 0, 0, 0, 0, 0,
146
147 // SIO
148 "SIOMULTI0",
149 "SIOMULTI1",
150 "SIOMULTI2",
151 "SIOMULTI3",
152 "SIOCNT",
153 "SIOMLT_SEND",
154 0,
155 0,
156 "KEYINPUT",
157 "KEYCNT",
158 "RCNT",
159 0,
160 0,
161 0,
162 0,
163 0,
164 "JOYCNT",
165 0,
166 0,
167 0,
168 0,
169 0,
170 0,
171 0,
172 "JOY_RECV_LO",
173 "JOY_RECV_HI",
174 "JOY_TRANS_LO",
175 "JOY_TRANS_HI",
176 "JOYSTAT",
177 0,
178 0,
179 0,
180
181 0, 0, 0, 0, 0, 0, 0, 0,
182 0, 0, 0, 0, 0, 0, 0, 0,
183 0, 0, 0, 0, 0, 0, 0, 0,
184 0, 0, 0, 0, 0, 0, 0, 0,
185 0, 0, 0, 0, 0, 0, 0, 0,
186 0, 0, 0, 0, 0, 0, 0, 0,
187 0, 0, 0, 0, 0, 0, 0, 0,
188 0, 0, 0, 0, 0, 0, 0, 0,
189 0, 0, 0, 0, 0, 0, 0, 0,
190 0, 0, 0, 0, 0, 0, 0, 0,
191
192 // Interrupts, etc
193 "IE",
194 "IF",
195 "WAITCNT",
196 0,
197 "IME"
198};
199
200static const int _isValidRegister[REG_MAX >> 1] = {
201 // Video
202 1, 0, 1, 1, 1, 1, 1, 1,
203 1, 1, 1, 1, 1, 1, 1, 1,
204 1, 1, 1, 1, 1, 1, 1, 1,
205 1, 1, 1, 1, 1, 1, 1, 1,
206 1, 1, 1, 1, 1, 1, 1, 0,
207 1, 1, 1, 0, 0, 0, 0, 0,
208 // Audio
209 1, 1, 1, 0, 1, 0, 1, 0,
210 1, 1, 1, 0, 1, 0, 1, 0,
211 1, 1, 1, 0, 1, 0, 0, 0,
212 1, 1, 1, 1, 1, 1, 1, 1,
213 1, 1, 1, 1, 1, 0, 0, 0,
214 // DMA
215 1, 1, 1, 1, 1, 1, 1, 1,
216 1, 1, 1, 1, 1, 1, 1, 1,
217 1, 1, 1, 1, 1, 1, 1, 1,
218 0, 0, 0, 0, 0, 0, 0, 0,
219 0, 0, 0, 0, 0, 0, 0, 0,
220 // Timers
221 1, 1, 1, 1, 1, 1, 1, 1,
222 0, 0, 0, 0, 0, 0, 0, 0,
223 // SIO
224 1, 1, 1, 1, 1, 0, 0, 0,
225 1, 1, 1, 0, 0, 0, 0, 0,
226 1, 0, 0, 0, 0, 0, 0, 0,
227 1, 0, 1, 0, 1, 0, 0, 0,
228 0, 0, 0, 0, 0, 0, 0, 0,
229 0, 0, 0, 0, 0, 0, 0, 0,
230 0, 0, 0, 0, 0, 0, 0, 0,
231 0, 0, 0, 0, 0, 0, 0, 0,
232 0, 0, 0, 0, 0, 0, 0, 0,
233 0, 0, 0, 0, 0, 0, 0, 0,
234 0, 0, 0, 0, 0, 0, 0, 0,
235 0, 0, 0, 0, 0, 0, 0, 0,
236 0, 0, 0, 0, 0, 0, 0, 0,
237 0, 0, 0, 0, 0, 0, 0, 0,
238 // Interrupts
239 1, 1, 1, 0, 1
240};
241
242static const int _isSpecialRegister[REG_MAX >> 1] = {
243 // Video
244 0, 0, 1, 1, 0, 0, 0, 0,
245 0, 0, 0, 0, 0, 0, 0, 0,
246 0, 0, 0, 0, 0, 0, 0, 0,
247 0, 0, 0, 0, 0, 0, 0, 0,
248 0, 0, 0, 0, 0, 0, 0, 0,
249 0, 0, 0, 0, 0, 0, 0, 0,
250 // Audio
251 0, 0, 0, 0, 0, 0, 0, 0,
252 0, 0, 0, 0, 0, 0, 0, 0,
253 0, 0, 0, 0, 0, 0, 0, 0,
254 1, 1, 1, 1, 1, 1, 1, 1,
255 1, 1, 1, 1, 0, 0, 0, 0,
256 // DMA
257 0, 0, 0, 0, 0, 1, 0, 0,
258 0, 0, 0, 1, 0, 0, 0, 0,
259 0, 1, 0, 0, 0, 0, 0, 1,
260 0, 0, 0, 0, 0, 0, 0, 0,
261 0, 0, 0, 0, 0, 0, 0, 0,
262 // Timers
263 1, 1, 1, 1, 1, 1, 1, 1,
264 0, 0, 0, 0, 0, 0, 0, 0,
265 // SIO
266 1, 1, 1, 1, 1, 0, 0, 0,
267 1, 1, 1, 0, 0, 0, 0, 0,
268 1, 0, 0, 0, 0, 0, 0, 0,
269 1, 0, 1, 0, 1, 0, 0, 0,
270 0, 0, 0, 0, 0, 0, 0, 0,
271 0, 0, 0, 0, 0, 0, 0, 0,
272 0, 0, 0, 0, 0, 0, 0, 0,
273 0, 0, 0, 0, 0, 0, 0, 0,
274 0, 0, 0, 0, 0, 0, 0, 0,
275 0, 0, 0, 0, 0, 0, 0, 0,
276 0, 0, 0, 0, 0, 0, 0, 0,
277 0, 0, 0, 0, 0, 0, 0, 0,
278 0, 0, 0, 0, 0, 0, 0, 0,
279 0, 0, 0, 0, 0, 0, 0, 0,
280 // Interrupts
281 1, 1, 0, 0, 1
282};
283
284void GBAIOInit(struct GBA* gba) {
285 gba->memory.io[REG_DISPCNT >> 1] = 0x0080;
286 gba->memory.io[REG_RCNT >> 1] = RCNT_INITIAL;
287 gba->memory.io[REG_KEYINPUT >> 1] = 0x3FF;
288 gba->memory.io[REG_SOUNDBIAS >> 1] = 0x200;
289 gba->memory.io[REG_BG2PA >> 1] = 0x100;
290 gba->memory.io[REG_BG2PD >> 1] = 0x100;
291 gba->memory.io[REG_BG3PA >> 1] = 0x100;
292 gba->memory.io[REG_BG3PD >> 1] = 0x100;
293}
294
295void GBAIOWrite(struct GBA* gba, uint32_t address, uint16_t value) {
296 if (address < REG_SOUND1CNT_LO && address != REG_DISPSTAT) {
297 value = gba->video.renderer->writeVideoRegister(gba->video.renderer, address, value);
298 } else {
299 switch (address) {
300 // Video
301 case REG_DISPSTAT:
302 value &= 0xFFF8;
303 GBAVideoWriteDISPSTAT(&gba->video, value);
304 return;
305
306 // Audio
307 case REG_SOUND1CNT_LO:
308 GBAAudioWriteSOUND1CNT_LO(&gba->audio, value);
309 value &= 0x00FF;
310 break;
311 case REG_SOUND1CNT_HI:
312 GBAAudioWriteSOUND1CNT_HI(&gba->audio, value);
313 break;
314 case REG_SOUND1CNT_X:
315 GBAAudioWriteSOUND1CNT_X(&gba->audio, value);
316 value &= 0x47FF;
317 break;
318 case REG_SOUND2CNT_LO:
319 GBAAudioWriteSOUND2CNT_LO(&gba->audio, value);
320 break;
321 case REG_SOUND2CNT_HI:
322 GBAAudioWriteSOUND2CNT_HI(&gba->audio, value);
323 value &= 0x47FF;
324 break;
325 case REG_SOUND3CNT_LO:
326 GBAAudioWriteSOUND3CNT_LO(&gba->audio, value);
327 value &= 0x00E0;
328 break;
329 case REG_SOUND3CNT_HI:
330 GBAAudioWriteSOUND3CNT_HI(&gba->audio, value);
331 value &= 0xE03F;
332 break;
333 case REG_SOUND3CNT_X:
334 GBAAudioWriteSOUND3CNT_X(&gba->audio, value);
335 // TODO: The low bits need to not be readable, but still 8-bit writable
336 value &= 0x47FF;
337 break;
338 case REG_SOUND4CNT_LO:
339 GBAAudioWriteSOUND4CNT_LO(&gba->audio, value);
340 value &= 0xFF3F;
341 break;
342 case REG_SOUND4CNT_HI:
343 GBAAudioWriteSOUND4CNT_HI(&gba->audio, value);
344 value &= 0x40FF;
345 break;
346 case REG_SOUNDCNT_LO:
347 GBAAudioWriteSOUNDCNT_LO(&gba->audio, value);
348 break;
349 case REG_SOUNDCNT_HI:
350 GBAAudioWriteSOUNDCNT_HI(&gba->audio, value);
351 break;
352 case REG_SOUNDCNT_X:
353 GBAAudioWriteSOUNDCNT_X(&gba->audio, value);
354 value &= 0xFFFF;
355 value |= gba->memory.io[REG_SOUNDCNT_X >> 1] & 0xF;
356 break;
357 case REG_SOUNDBIAS:
358 GBAAudioWriteSOUNDBIAS(&gba->audio, value);
359 break;
360
361 case REG_WAVE_RAM0_LO:
362 case REG_WAVE_RAM1_LO:
363 case REG_WAVE_RAM2_LO:
364 case REG_WAVE_RAM3_LO:
365 GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
366 break;
367
368 case REG_WAVE_RAM0_HI:
369 case REG_WAVE_RAM1_HI:
370 case REG_WAVE_RAM2_HI:
371 case REG_WAVE_RAM3_HI:
372 GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
373 break;
374
375 case REG_FIFO_A_LO:
376 case REG_FIFO_B_LO:
377 GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
378 break;
379
380 case REG_FIFO_A_HI:
381 case REG_FIFO_B_HI:
382 GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
383 break;
384
385 // DMA
386 case REG_DMA0SAD_LO:
387 case REG_DMA0DAD_LO:
388 case REG_DMA1SAD_LO:
389 case REG_DMA1DAD_LO:
390 case REG_DMA2SAD_LO:
391 case REG_DMA2DAD_LO:
392 case REG_DMA3SAD_LO:
393 case REG_DMA3DAD_LO:
394 GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
395 break;
396
397 case REG_DMA0SAD_HI:
398 case REG_DMA0DAD_HI:
399 case REG_DMA1SAD_HI:
400 case REG_DMA1DAD_HI:
401 case REG_DMA2SAD_HI:
402 case REG_DMA2DAD_HI:
403 case REG_DMA3SAD_HI:
404 case REG_DMA3DAD_HI:
405 GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
406 break;
407
408 case REG_DMA0CNT_LO:
409 GBAMemoryWriteDMACNT_LO(gba, 0, value);
410 break;
411 case REG_DMA0CNT_HI:
412 value = GBAMemoryWriteDMACNT_HI(gba, 0, value);
413 break;
414 case REG_DMA1CNT_LO:
415 GBAMemoryWriteDMACNT_LO(gba, 1, value);
416 break;
417 case REG_DMA1CNT_HI:
418 value = GBAMemoryWriteDMACNT_HI(gba, 1, value);
419 break;
420 case REG_DMA2CNT_LO:
421 GBAMemoryWriteDMACNT_LO(gba, 2, value);
422 break;
423 case REG_DMA2CNT_HI:
424 value = GBAMemoryWriteDMACNT_HI(gba, 2, value);
425 break;
426 case REG_DMA3CNT_LO:
427 GBAMemoryWriteDMACNT_LO(gba, 3, value);
428 break;
429 case REG_DMA3CNT_HI:
430 value = GBAMemoryWriteDMACNT_HI(gba, 3, value);
431 break;
432
433 // Timers
434 case REG_TM0CNT_LO:
435 GBATimerWriteTMCNT_LO(gba, 0, value);
436 return;
437 case REG_TM1CNT_LO:
438 GBATimerWriteTMCNT_LO(gba, 1, value);
439 return;
440 case REG_TM2CNT_LO:
441 GBATimerWriteTMCNT_LO(gba, 2, value);
442 return;
443 case REG_TM3CNT_LO:
444 GBATimerWriteTMCNT_LO(gba, 3, value);
445 return;
446
447 case REG_TM0CNT_HI:
448 value &= 0x00C7;
449 GBATimerWriteTMCNT_HI(gba, 0, value);
450 break;
451 case REG_TM1CNT_HI:
452 value &= 0x00C7;
453 GBATimerWriteTMCNT_HI(gba, 1, value);
454 break;
455 case REG_TM2CNT_HI:
456 value &= 0x00C7;
457 GBATimerWriteTMCNT_HI(gba, 2, value);
458 break;
459 case REG_TM3CNT_HI:
460 value &= 0x00C7;
461 GBATimerWriteTMCNT_HI(gba, 3, value);
462 break;
463
464 // SIO
465 case REG_SIOCNT:
466 GBASIOWriteSIOCNT(&gba->sio, value);
467 break;
468 case REG_RCNT:
469 value &= 0xC1FF;
470 GBASIOWriteRCNT(&gba->sio, value);
471 break;
472 case REG_SIOMLT_SEND:
473 GBASIOWriteSIOMLT_SEND(&gba->sio, value);
474 break;
475
476 // Interrupts and misc
477 case REG_WAITCNT:
478 GBAAdjustWaitstates(gba, value);
479 break;
480 case REG_IE:
481 GBAWriteIE(gba, value);
482 break;
483 case REG_IF:
484 value = gba->memory.io[REG_IF >> 1] & ~value;
485 break;
486 case REG_IME:
487 GBAWriteIME(gba, value);
488 break;
489 case REG_MAX:
490 // Some bad interrupt libraries will write to this
491 break;
492 default:
493 GBALog(gba, GBA_LOG_STUB, "Stub I/O register write: %03x", address);
494 if (address >= REG_MAX) {
495 GBALog(gba, GBA_LOG_GAME_ERROR, "Write to unused I/O register: %03X", address);
496 return;
497 }
498 break;
499 }
500 }
501 gba->memory.io[address >> 1] = value;
502}
503
504void GBAIOWrite8(struct GBA* gba, uint32_t address, uint8_t value) {
505 if (address == REG_HALTCNT) {
506 value &= 0x80;
507 if (!value) {
508 GBAHalt(gba);
509 } else {
510 GBAStop(gba);
511 }
512 return;
513 }
514 uint16_t value16 = value << (8 * (address & 1));
515 value16 |= (gba->memory.io[(address & (SIZE_IO - 1)) >> 1]) & ~(0xFF << (8 * (address & 1)));
516 GBAIOWrite(gba, address & 0xFFFFFFFE, value16);
517}
518
519void GBAIOWrite32(struct GBA* gba, uint32_t address, uint32_t value) {
520 switch (address) {
521 case REG_WAVE_RAM0_LO:
522 GBAAudioWriteWaveRAM(&gba->audio, 0, value);
523 break;
524 case REG_WAVE_RAM1_LO:
525 GBAAudioWriteWaveRAM(&gba->audio, 1, value);
526 break;
527 case REG_WAVE_RAM2_LO:
528 GBAAudioWriteWaveRAM(&gba->audio, 2, value);
529 break;
530 case REG_WAVE_RAM3_LO:
531 GBAAudioWriteWaveRAM(&gba->audio, 3, value);
532 break;
533 case REG_FIFO_A_LO:
534 case REG_FIFO_B_LO:
535 GBAAudioWriteFIFO(&gba->audio, address, value);
536 break;
537 case REG_DMA0SAD_LO:
538 GBAMemoryWriteDMASAD(gba, 0, value);
539 break;
540 case REG_DMA0DAD_LO:
541 GBAMemoryWriteDMADAD(gba, 0, value);
542 break;
543 case REG_DMA1SAD_LO:
544 GBAMemoryWriteDMASAD(gba, 1, value);
545 break;
546 case REG_DMA1DAD_LO:
547 GBAMemoryWriteDMADAD(gba, 1, value);
548 break;
549 case REG_DMA2SAD_LO:
550 GBAMemoryWriteDMASAD(gba, 2, value);
551 break;
552 case REG_DMA2DAD_LO:
553 GBAMemoryWriteDMADAD(gba, 2, value);
554 break;
555 case REG_DMA3SAD_LO:
556 GBAMemoryWriteDMASAD(gba, 3, value);
557 break;
558 case REG_DMA3DAD_LO:
559 GBAMemoryWriteDMADAD(gba, 3, value);
560 break;
561 default:
562 GBAIOWrite(gba, address, value & 0xFFFF);
563 GBAIOWrite(gba, address | 2, value >> 16);
564 return;
565 }
566 gba->memory.io[address >> 1] = value;
567 gba->memory.io[(address >> 1) + 1] = value >> 16;
568}
569
570uint16_t GBAIORead(struct GBA* gba, uint32_t address) {
571 gba->haltPending = false; // IO reads need to invalidate detected idle loops
572 switch (address) {
573 case REG_TM0CNT_LO:
574 GBATimerUpdateRegister(gba, 0);
575 break;
576 case REG_TM1CNT_LO:
577 GBATimerUpdateRegister(gba, 1);
578 break;
579 case REG_TM2CNT_LO:
580 GBATimerUpdateRegister(gba, 2);
581 break;
582 case REG_TM3CNT_LO:
583 GBATimerUpdateRegister(gba, 3);
584 break;
585
586 case REG_KEYINPUT:
587 if (gba->rr && gba->rr->isPlaying(gba->rr)) {
588 return 0x3FF ^ gba->rr->queryInput(gba->rr);
589 } else {
590 uint16_t input = 0x3FF;
591 if (gba->keyCallback) {
592 input = gba->keyCallback->readKeys(gba->keyCallback);
593 } else if (gba->keySource) {
594 input = *gba->keySource;
595 }
596 if (gba->rr && gba->rr->isRecording(gba->rr)) {
597 gba->rr->logInput(gba->rr, input);
598 }
599 return 0x3FF ^ input;
600 }
601
602 case REG_SIOCNT:
603 return gba->sio.siocnt;
604 case REG_RCNT:
605 return gba->sio.rcnt;
606
607 case REG_DMA0CNT_LO:
608 case REG_DMA1CNT_LO:
609 case REG_DMA2CNT_LO:
610 case REG_DMA3CNT_LO:
611 // Write-only register
612 return 0;
613 case REG_DISPCNT:
614 case REG_DISPSTAT:
615 case REG_VCOUNT:
616 case REG_BG0CNT:
617 case REG_BG1CNT:
618 case REG_BG2CNT:
619 case REG_BG3CNT:
620 case REG_WININ:
621 case REG_WINOUT:
622 case REG_BLDCNT:
623 case REG_BLDALPHA:
624 case REG_SOUND1CNT_LO:
625 case REG_SOUND1CNT_HI:
626 case REG_SOUND1CNT_X:
627 case REG_SOUND2CNT_LO:
628 case REG_SOUND2CNT_HI:
629 case REG_SOUND3CNT_LO:
630 case REG_SOUND3CNT_HI:
631 case REG_SOUND3CNT_X:
632 case REG_SOUND4CNT_LO:
633 case REG_SOUND4CNT_HI:
634 case REG_SOUNDCNT_LO:
635 case REG_SOUNDCNT_HI:
636 case REG_DMA0CNT_HI:
637 case REG_DMA1CNT_HI:
638 case REG_DMA2CNT_HI:
639 case REG_DMA3CNT_HI:
640 case REG_SIOMULTI0:
641 case REG_SIOMULTI1:
642 case REG_SIOMULTI2:
643 case REG_SIOMULTI3:
644 case REG_SIOMLT_SEND:
645 case REG_IE:
646 case REG_IF:
647 case REG_WAITCNT:
648 case REG_IME:
649 // Handled transparently by registers
650 break;
651 case REG_MAX:
652 // Some bad interrupt libraries will read from this
653 break;
654 default:
655 GBALog(gba, GBA_LOG_STUB, "Stub I/O register read: %03x", address);
656 if (address >= REG_MAX) {
657 GBALog(gba, GBA_LOG_GAME_ERROR, "Read from unused I/O register: %03X", address);
658 return 0; // TODO: Reuse LOAD_BAD
659 }
660 break;
661 }
662 return gba->memory.io[address >> 1];
663}
664
665void GBAIOSerialize(struct GBA* gba, struct GBASerializedState* state) {
666 int i;
667 for (i = 0; i < REG_MAX; i += 2) {
668 if (_isSpecialRegister[i >> 1]) {
669 state->io[i >> 1] = gba->memory.io[i >> 1];
670 } else if (_isValidRegister[i >> 1]) {
671 state->io[i >> 1] = GBAIORead(gba, i);
672 }
673 }
674
675 for (i = 0; i < 4; ++i) {
676 state->io[(REG_DMA0CNT_LO + i * 12) >> 1] = gba->memory.io[(REG_DMA0CNT_LO + i * 12) >> 1];
677 state->dma[i].nextSource = gba->memory.dma[i].nextSource;
678 state->dma[i].nextDest = gba->memory.dma[i].nextDest;
679 state->dma[i].nextCount = gba->memory.dma[i].nextCount;
680 state->dma[i].nextEvent = gba->memory.dma[i].nextEvent;
681 }
682
683 memcpy(state->timers, gba->timers, sizeof(state->timers));
684 GBAHardwareSerialize(&gba->memory.hw, state);
685}
686
687void GBAIODeserialize(struct GBA* gba, const struct GBASerializedState* state) {
688 int i;
689 for (i = 0; i < REG_MAX; i += 2) {
690 if (_isSpecialRegister[i >> 1]) {
691 gba->memory.io[i >> 1] = state->io[i >> 1];
692 } else if (_isValidRegister[i >> 1]) {
693 GBAIOWrite(gba, i, state->io[i >> 1]);
694 }
695 }
696
697 gba->timersEnabled = 0;
698 memcpy(gba->timers, state->timers, sizeof(gba->timers));
699 for (i = 0; i < 4; ++i) {
700 gba->memory.dma[i].reg = state->io[(REG_DMA0CNT_HI + i * 12) >> 1];
701 gba->memory.dma[i].nextSource = state->dma[i].nextSource;
702 gba->memory.dma[i].nextDest = state->dma[i].nextDest;
703 gba->memory.dma[i].nextCount = state->dma[i].nextCount;
704 gba->memory.dma[i].nextEvent = state->dma[i].nextEvent;
705 if (GBADMARegisterGetTiming(gba->memory.dma[i].reg) != DMA_TIMING_NOW) {
706 GBAMemoryScheduleDMA(gba, i, &gba->memory.dma[i]);
707 }
708
709 if (gba->timers[i].enable) {
710 gba->timersEnabled |= 1 << i;
711 }
712 }
713 GBAMemoryUpdateDMAs(gba, 0);
714 GBAHardwareDeserialize(&gba->memory.hw, state);
715}