src/gb/gb.c (view raw)
1/* Copyright (c) 2013-2016 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 <mgba/internal/gb/gb.h>
7
8#include <mgba/internal/gb/io.h>
9#include <mgba/internal/gb/mbc.h>
10#include <mgba/internal/lr35902/lr35902.h>
11
12#include <mgba/core/core.h>
13#include <mgba/core/cheats.h>
14#include <mgba-util/crc32.h>
15#include <mgba-util/memory.h>
16#include <mgba-util/math.h>
17#include <mgba-util/patch.h>
18#include <mgba-util/vfs.h>
19
20#define CLEANUP_THRESHOLD 15
21
22const uint32_t CGB_LR35902_FREQUENCY = 0x800000;
23const uint32_t SGB_LR35902_FREQUENCY = 0x418B1E;
24
25const uint32_t GB_COMPONENT_MAGIC = 0x400000;
26
27static const uint8_t _knownHeader[4] = { 0xCE, 0xED, 0x66, 0x66};
28
29#define DMG_BIOS_CHECKSUM 0xC2F5CC97
30#define DMG_2_BIOS_CHECKSUM 0x59C8598E
31#define MGB_BIOS_CHECKSUM 0xE6920754
32#define SGB_BIOS_CHECKSUM 0xEC8A83B9
33#define CGB_BIOS_CHECKSUM 0x41884E46
34
35mLOG_DEFINE_CATEGORY(GB, "GB", "gb");
36
37static void GBInit(void* cpu, struct mCPUComponent* component);
38static void GBDeinit(struct mCPUComponent* component);
39static void GBInterruptHandlerInit(struct LR35902InterruptHandler* irqh);
40static void GBProcessEvents(struct LR35902Core* cpu);
41static void GBSetInterrupts(struct LR35902Core* cpu, bool enable);
42static uint16_t GBIRQVector(struct LR35902Core* cpu);
43static void GBIllegal(struct LR35902Core* cpu);
44static void GBStop(struct LR35902Core* cpu);
45
46static void _enableInterrupts(struct mTiming* timing, void* user, uint32_t cyclesLate);
47
48#ifdef FIXED_ROM_BUFFER
49extern uint32_t* romBuffer;
50extern size_t romBufferSize;
51#endif
52
53void GBCreate(struct GB* gb) {
54 gb->d.id = GB_COMPONENT_MAGIC;
55 gb->d.init = GBInit;
56 gb->d.deinit = GBDeinit;
57}
58
59static void GBInit(void* cpu, struct mCPUComponent* component) {
60 struct GB* gb = (struct GB*) component;
61 gb->cpu = cpu;
62 gb->sync = NULL;
63
64 GBInterruptHandlerInit(&gb->cpu->irqh);
65 GBMemoryInit(gb);
66
67 gb->video.p = gb;
68 GBVideoInit(&gb->video);
69
70 gb->audio.p = gb;
71 GBAudioInit(&gb->audio, 2048, &gb->memory.io[REG_NR52], GB_AUDIO_DMG); // TODO: Remove magic constant
72
73 gb->sio.p = gb;
74 GBSIOInit(&gb->sio);
75
76 gb->timer.p = gb;
77
78 gb->model = GB_MODEL_AUTODETECT;
79
80 gb->biosVf = NULL;
81 gb->romVf = NULL;
82 gb->sramVf = NULL;
83 gb->sramRealVf = NULL;
84
85 gb->isPristine = false;
86 gb->pristineRomSize = 0;
87 gb->yankedRomSize = 0;
88
89 mCoreCallbacksListInit(&gb->coreCallbacks, 0);
90 gb->stream = NULL;
91
92 mTimingInit(&gb->timing, &gb->cpu->cycles, &gb->cpu->nextEvent);
93 gb->audio.timing = &gb->timing;
94
95 gb->eiPending.name = "GB EI";
96 gb->eiPending.callback = _enableInterrupts;
97 gb->eiPending.context = gb;
98 gb->eiPending.priority = 0;
99}
100
101static void GBDeinit(struct mCPUComponent* component) {
102 struct GB* gb = (struct GB*) component;
103 mTimingDeinit(&gb->timing);
104}
105
106bool GBLoadROM(struct GB* gb, struct VFile* vf) {
107 if (!vf) {
108 return false;
109 }
110 GBUnloadROM(gb);
111 gb->romVf = vf;
112 gb->pristineRomSize = vf->size(vf);
113 vf->seek(vf, 0, SEEK_SET);
114 gb->isPristine = true;
115#ifdef FIXED_ROM_BUFFER
116 if (gb->pristineRomSize <= romBufferSize) {
117 gb->memory.rom = romBuffer;
118 vf->read(vf, romBuffer, gb->pristineRomSize);
119 }
120#else
121 gb->memory.rom = vf->map(vf, gb->pristineRomSize, MAP_READ);
122#endif
123 if (!gb->memory.rom) {
124 return false;
125 }
126 gb->yankedRomSize = 0;
127 gb->memory.romBase = gb->memory.rom;
128 gb->memory.romSize = gb->pristineRomSize;
129 gb->romCrc32 = doCrc32(gb->memory.rom, gb->memory.romSize);
130 GBMBCInit(gb);
131
132 if (gb->cpu) {
133 struct LR35902Core* cpu = gb->cpu;
134 cpu->memory.setActiveRegion(cpu, cpu->pc);
135 }
136
137 // TODO: error check
138 return true;
139}
140
141static void GBSramDeinit(struct GB* gb) {
142 if (gb->sramVf) {
143 gb->sramVf->unmap(gb->sramVf, gb->memory.sram, gb->sramSize);
144 if (gb->memory.mbcType == GB_MBC3_RTC && gb->sramVf == gb->sramRealVf) {
145 GBMBCRTCWrite(gb);
146 }
147 gb->sramVf = NULL;
148 } else if (gb->memory.sram) {
149 mappedMemoryFree(gb->memory.sram, gb->sramSize);
150 }
151 gb->memory.sram = 0;
152}
153
154bool GBLoadSave(struct GB* gb, struct VFile* vf) {
155 GBSramDeinit(gb);
156 gb->sramVf = vf;
157 gb->sramRealVf = vf;
158 if (gb->sramSize) {
159 GBResizeSram(gb, gb->sramSize);
160 }
161 return vf;
162}
163
164void GBResizeSram(struct GB* gb, size_t size) {
165 if (gb->memory.sram && size <= gb->sramSize) {
166 return;
167 }
168 struct VFile* vf = gb->sramVf;
169 if (vf) {
170 if (vf == gb->sramRealVf) {
171 ssize_t vfSize = vf->size(vf);
172 if (vfSize >= 0 && (size_t) vfSize < size) {
173 uint8_t extdataBuffer[0x100];
174 if (vfSize & 0xFF) {
175 vf->seek(vf, -(vfSize & 0xFF), SEEK_END);
176 vf->read(vf, extdataBuffer, vfSize & 0xFF);
177 }
178 if (gb->memory.sram) {
179 vf->unmap(vf, gb->memory.sram, gb->sramSize);
180 }
181 vf->truncate(vf, size + (vfSize & 0xFF));
182 if (vfSize & 0xFF) {
183 vf->seek(vf, size, SEEK_SET);
184 vf->write(vf, extdataBuffer, vfSize & 0xFF);
185 }
186 gb->memory.sram = vf->map(vf, size, MAP_WRITE);
187 memset(&gb->memory.sram[gb->sramSize], 0xFF, size - gb->sramSize);
188 } else if (size > gb->sramSize || !gb->memory.sram) {
189 if (gb->memory.sram) {
190 vf->unmap(vf, gb->memory.sram, gb->sramSize);
191 }
192 gb->memory.sram = vf->map(vf, size, MAP_WRITE);
193 }
194 } else {
195 if (gb->memory.sram) {
196 vf->unmap(vf, gb->memory.sram, gb->sramSize);
197 }
198 gb->memory.sram = vf->map(vf, size, MAP_READ);
199 }
200 if (gb->memory.sram == (void*) -1) {
201 gb->memory.sram = NULL;
202 }
203 } else {
204 uint8_t* newSram = anonymousMemoryMap(size);
205 if (gb->memory.sram) {
206 if (size > gb->sramSize) {
207 memcpy(newSram, gb->memory.sram, gb->sramSize);
208 memset(&newSram[gb->sramSize], 0xFF, size - gb->sramSize);
209 } else {
210 memcpy(newSram, gb->memory.sram, size);
211 }
212 mappedMemoryFree(gb->memory.sram, gb->sramSize);
213 } else {
214 memset(newSram, 0xFF, size);
215 }
216 gb->memory.sram = newSram;
217 }
218 if (gb->sramSize < size) {
219 gb->sramSize = size;
220 }
221}
222
223void GBSramClean(struct GB* gb, uint32_t frameCount) {
224 // TODO: Share with GBASavedataClean
225 if (!gb->sramVf) {
226 return;
227 }
228 if (gb->sramDirty & GB_SRAM_DIRT_NEW) {
229 gb->sramDirtAge = frameCount;
230 gb->sramDirty &= ~GB_SRAM_DIRT_NEW;
231 if (!(gb->sramDirty & GB_SRAM_DIRT_SEEN)) {
232 gb->sramDirty |= GB_SRAM_DIRT_SEEN;
233 }
234 } else if ((gb->sramDirty & GB_SRAM_DIRT_SEEN) && frameCount - gb->sramDirtAge > CLEANUP_THRESHOLD) {
235 if (gb->sramMaskWriteback) {
236 GBSavedataUnmask(gb);
237 }
238 if (gb->memory.mbcType == GB_MBC3_RTC) {
239 GBMBCRTCWrite(gb);
240 }
241 gb->sramDirty = 0;
242 if (gb->memory.sram && gb->sramVf->sync(gb->sramVf, gb->memory.sram, gb->sramSize)) {
243 mLOG(GB_MEM, INFO, "Savedata synced");
244 } else {
245 mLOG(GB_MEM, INFO, "Savedata failed to sync!");
246 }
247 }
248}
249
250void GBSavedataMask(struct GB* gb, struct VFile* vf, bool writeback) {
251 GBSramDeinit(gb);
252 gb->sramVf = vf;
253 gb->sramMaskWriteback = writeback;
254 gb->memory.sram = vf->map(vf, gb->sramSize, MAP_READ);
255 GBMBCSwitchSramBank(gb, gb->memory.sramCurrentBank);
256}
257
258void GBSavedataUnmask(struct GB* gb) {
259 if (gb->sramVf == gb->sramRealVf) {
260 return;
261 }
262 struct VFile* vf = gb->sramVf;
263 GBSramDeinit(gb);
264 gb->sramVf = gb->sramRealVf;
265 gb->memory.sram = gb->sramVf->map(gb->sramVf, gb->sramSize, MAP_WRITE);
266 if (gb->sramMaskWriteback) {
267 vf->seek(vf, 0, SEEK_SET);
268 vf->read(vf, gb->memory.sram, gb->sramSize);
269 gb->sramMaskWriteback = false;
270 }
271 vf->close(vf);
272}
273
274void GBUnloadROM(struct GB* gb) {
275 // TODO: Share with GBAUnloadROM
276 if (gb->memory.rom && gb->memory.romBase != gb->memory.rom && !gb->isPristine) {
277 free(gb->memory.romBase);
278 }
279 if (gb->memory.rom && !gb->isPristine) {
280 if (gb->yankedRomSize) {
281 gb->yankedRomSize = 0;
282 }
283 mappedMemoryFree(gb->memory.rom, GB_SIZE_CART_MAX);
284 }
285
286 if (gb->romVf) {
287#ifndef FIXED_ROM_BUFFER
288 gb->romVf->unmap(gb->romVf, gb->memory.rom, gb->pristineRomSize);
289#endif
290 gb->romVf->close(gb->romVf);
291 gb->romVf = NULL;
292 }
293 gb->memory.rom = NULL;
294 gb->memory.mbcType = GB_MBC_AUTODETECT;
295 gb->isPristine = false;
296
297 gb->sramMaskWriteback = false;
298 GBSavedataUnmask(gb);
299 GBSramDeinit(gb);
300 if (gb->sramRealVf) {
301 gb->sramRealVf->close(gb->sramRealVf);
302 }
303 gb->sramRealVf = NULL;
304 gb->sramVf = NULL;
305 if (gb->memory.cam && gb->memory.cam->stopRequestImage) {
306 gb->memory.cam->stopRequestImage(gb->memory.cam);
307 }
308}
309
310void GBSynthesizeROM(struct VFile* vf) {
311 if (!vf) {
312 return;
313 }
314 const struct GBCartridge cart = {
315 .logo = { _knownHeader[0], _knownHeader[1], _knownHeader[2], _knownHeader[3]}
316 };
317
318 vf->seek(vf, 0x100, SEEK_SET);
319 vf->write(vf, &cart, sizeof(cart));
320}
321
322void GBLoadBIOS(struct GB* gb, struct VFile* vf) {
323 gb->biosVf = vf;
324}
325
326void GBApplyPatch(struct GB* gb, struct Patch* patch) {
327 size_t patchedSize = patch->outputSize(patch, gb->memory.romSize);
328 if (!patchedSize) {
329 return;
330 }
331 if (patchedSize > GB_SIZE_CART_MAX) {
332 patchedSize = GB_SIZE_CART_MAX;
333 }
334 void* newRom = anonymousMemoryMap(GB_SIZE_CART_MAX);
335 if (!patch->applyPatch(patch, gb->memory.rom, gb->pristineRomSize, newRom, patchedSize)) {
336 mappedMemoryFree(newRom, GB_SIZE_CART_MAX);
337 return;
338 }
339 if (gb->romVf) {
340#ifndef FIXED_ROM_BUFFER
341 gb->romVf->unmap(gb->romVf, gb->memory.rom, gb->pristineRomSize);
342#endif
343 gb->romVf->close(gb->romVf);
344 gb->romVf = NULL;
345 }
346 gb->isPristine = false;
347 if (gb->memory.romBase == gb->memory.rom) {
348 gb->memory.romBase = newRom;
349 }
350 gb->memory.rom = newRom;
351 gb->memory.romSize = patchedSize;
352 gb->romCrc32 = doCrc32(gb->memory.rom, gb->memory.romSize);
353 gb->cpu->memory.setActiveRegion(gb->cpu, gb->cpu->pc);
354}
355
356void GBDestroy(struct GB* gb) {
357 GBUnloadROM(gb);
358
359 if (gb->biosVf) {
360 gb->biosVf->close(gb->biosVf);
361 gb->biosVf = 0;
362 }
363
364 GBMemoryDeinit(gb);
365 GBAudioDeinit(&gb->audio);
366 GBVideoDeinit(&gb->video);
367 GBSIODeinit(&gb->sio);
368 mCoreCallbacksListDeinit(&gb->coreCallbacks);
369}
370
371void GBInterruptHandlerInit(struct LR35902InterruptHandler* irqh) {
372 irqh->reset = GBReset;
373 irqh->processEvents = GBProcessEvents;
374 irqh->setInterrupts = GBSetInterrupts;
375 irqh->irqVector = GBIRQVector;
376 irqh->hitIllegal = GBIllegal;
377 irqh->stop = GBStop;
378 irqh->halt = GBHalt;
379}
380
381static uint32_t _GBBiosCRC32(struct VFile* vf) {
382 ssize_t size = vf->size(vf);
383 if (size <= 0 || size > GB_SIZE_CART_BANK0) {
384 return 0;
385 }
386 void* bios = vf->map(vf, size, MAP_READ);
387 uint32_t biosCrc = doCrc32(bios, size);
388 vf->unmap(vf, bios, size);
389 return biosCrc;
390}
391
392bool GBIsBIOS(struct VFile* vf) {
393 switch (_GBBiosCRC32(vf)) {
394 case DMG_BIOS_CHECKSUM:
395 case DMG_2_BIOS_CHECKSUM:
396 case MGB_BIOS_CHECKSUM:
397 case SGB_BIOS_CHECKSUM:
398 case CGB_BIOS_CHECKSUM:
399 return true;
400 default:
401 return false;
402 }
403}
404
405void GBReset(struct LR35902Core* cpu) {
406 struct GB* gb = (struct GB*) cpu->master;
407 gb->memory.romBase = gb->memory.rom;
408 GBDetectModel(gb);
409
410 if (gb->biosVf) {
411 if (!GBIsBIOS(gb->biosVf)) {
412 gb->biosVf->close(gb->biosVf);
413 gb->biosVf = NULL;
414 } else {
415 gb->biosVf->seek(gb->biosVf, 0, SEEK_SET);
416 gb->memory.romBase = malloc(GB_SIZE_CART_BANK0);
417 ssize_t size = gb->biosVf->read(gb->biosVf, gb->memory.romBase, GB_SIZE_CART_BANK0);
418 memcpy(&gb->memory.romBase[size], &gb->memory.rom[size], GB_SIZE_CART_BANK0 - size);
419 if (size > 0x100) {
420 memcpy(&gb->memory.romBase[0x100], &gb->memory.rom[0x100], sizeof(struct GBCartridge));
421 }
422
423 cpu->a = 0;
424 cpu->f.packed = 0;
425 cpu->c = 0;
426 cpu->e = 0;
427 cpu->h = 0;
428 cpu->l = 0;
429 cpu->sp = 0;
430 cpu->pc = 0;
431 }
432 }
433
434 cpu->b = 0;
435 cpu->d = 0;
436
437 gb->timer.internalDiv = 0;
438
439 gb->cpuBlocked = false;
440 gb->earlyExit = false;
441 gb->doubleSpeed = 0;
442
443 if (gb->yankedRomSize) {
444 gb->memory.romSize = gb->yankedRomSize;
445 gb->yankedRomSize = 0;
446 }
447
448 gb->sgbBit = -1;
449 gb->currentSgbBits = 0;
450 memset(gb->sgbPacket, 0, sizeof(gb->sgbPacket));
451
452 mTimingClear(&gb->timing);
453
454 GBMemoryReset(gb);
455 GBVideoReset(&gb->video);
456 GBTimerReset(&gb->timer);
457 if (!gb->biosVf) {
458 GBSkipBIOS(gb);
459 } else {
460 mTimingSchedule(&gb->timing, &gb->timer.event, 0);
461 }
462
463 GBIOReset(gb);
464 GBAudioReset(&gb->audio);
465 GBSIOReset(&gb->sio);
466
467 cpu->memory.setActiveRegion(cpu, cpu->pc);
468
469 GBSavedataUnmask(gb);
470}
471
472void GBSkipBIOS(struct GB* gb) {
473 struct LR35902Core* cpu = gb->cpu;
474 int nextDiv = 0;
475
476 switch (gb->model) {
477 case GB_MODEL_AUTODETECT: // Silence warnings
478 gb->model = GB_MODEL_DMG;
479 case GB_MODEL_DMG:
480 cpu->a = 1;
481 cpu->f.packed = 0xB0;
482 cpu->c = 0x13;
483 cpu->e = 0xD8;
484 cpu->h = 1;
485 cpu->l = 0x4D;
486 gb->timer.internalDiv = 0xABC;
487 nextDiv = 4;
488 break;
489 case GB_MODEL_SGB:
490 cpu->a = 1;
491 cpu->f.packed = 0x00;
492 cpu->c = 0x14;
493 cpu->e = 0x00;
494 cpu->h = 0xC0;
495 cpu->l = 0x60;
496 gb->timer.internalDiv = 0xABC;
497 nextDiv = 4;
498 break;
499 case GB_MODEL_MGB:
500 cpu->a = 0xFF;
501 cpu->f.packed = 0xB0;
502 cpu->c = 0x13;
503 cpu->e = 0xD8;
504 cpu->h = 1;
505 cpu->l = 0x4D;
506 gb->timer.internalDiv = 0xABC;
507 nextDiv = 4;
508 break;
509 case GB_MODEL_SGB2:
510 cpu->a = 0xFF;
511 cpu->f.packed = 0x00;
512 cpu->c = 0x14;
513 cpu->e = 0x00;
514 cpu->h = 0xC0;
515 cpu->l = 0x60;
516 gb->timer.internalDiv = 0xABC;
517 nextDiv = 4;
518 break;
519 case GB_MODEL_AGB:
520 cpu->a = 0x11;
521 cpu->b = 1;
522 cpu->f.packed = 0x00;
523 cpu->c = 0;
524 cpu->e = 0x08;
525 cpu->h = 0;
526 cpu->l = 0x7C;
527 gb->timer.internalDiv = 0x1EA;
528 nextDiv = 0xC;
529 break;
530 case GB_MODEL_CGB:
531 cpu->a = 0x11;
532 cpu->f.packed = 0x80;
533 cpu->c = 0;
534 cpu->e = 0x08;
535 cpu->h = 0;
536 cpu->l = 0x7C;
537 gb->timer.internalDiv = 0x1EA;
538 nextDiv = 0xC;
539 break;
540 }
541
542 cpu->sp = 0xFFFE;
543 cpu->pc = 0x100;
544
545 mTimingDeschedule(&gb->timing, &gb->timer.event);
546 mTimingSchedule(&gb->timing, &gb->timer.event, 0);
547
548 if (gb->biosVf) {
549 GBUnmapBIOS(gb);
550 }
551}
552
553void GBUnmapBIOS(struct GB* gb) {
554 if (gb->memory.romBase < gb->memory.rom || gb->memory.romBase > &gb->memory.rom[gb->memory.romSize - 1]) {
555 free(gb->memory.romBase);
556 gb->memory.romBase = gb->memory.rom;
557 }
558}
559
560void GBDetectModel(struct GB* gb) {
561 if (gb->model != GB_MODEL_AUTODETECT) {
562 return;
563 }
564 if (gb->biosVf) {
565 switch (_GBBiosCRC32(gb->biosVf)) {
566 case DMG_BIOS_CHECKSUM:
567 case DMG_2_BIOS_CHECKSUM:
568 gb->model = GB_MODEL_DMG;
569 break;
570 case MGB_BIOS_CHECKSUM:
571 gb->model = GB_MODEL_MGB;
572 break;
573 case SGB_BIOS_CHECKSUM:
574 gb->model = GB_MODEL_SGB;
575 break;
576 case CGB_BIOS_CHECKSUM:
577 gb->model = GB_MODEL_CGB;
578 break;
579 default:
580 gb->biosVf->close(gb->biosVf);
581 gb->biosVf = NULL;
582 }
583 }
584 if (gb->model == GB_MODEL_AUTODETECT && gb->memory.rom) {
585 const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
586 if (cart->cgb & 0x80) {
587 gb->model = GB_MODEL_CGB;
588 } else if (cart->sgb == 0x03 && cart->oldLicensee == 0x33) {
589 gb->model = GB_MODEL_SGB;
590 } else {
591 gb->model = GB_MODEL_DMG;
592 }
593 }
594
595 switch (gb->model) {
596 case GB_MODEL_DMG:
597 case GB_MODEL_SGB:
598 case GB_MODEL_AUTODETECT: //Silence warnings
599 gb->audio.style = GB_AUDIO_DMG;
600 break;
601 case GB_MODEL_MGB:
602 case GB_MODEL_SGB2:
603 gb->audio.style = GB_AUDIO_MGB;
604 break;
605 case GB_MODEL_AGB:
606 case GB_MODEL_CGB:
607 gb->audio.style = GB_AUDIO_CGB;
608 break;
609 }
610}
611
612void GBUpdateIRQs(struct GB* gb) {
613 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
614 if (!irqs) {
615 return;
616 }
617 gb->cpu->halted = false;
618
619 if (!gb->memory.ime || gb->cpu->irqPending) {
620 return;
621 }
622 LR35902RaiseIRQ(gb->cpu);
623}
624
625void GBProcessEvents(struct LR35902Core* cpu) {
626 struct GB* gb = (struct GB*) cpu->master;
627 do {
628 int32_t cycles = cpu->cycles;
629 int32_t nextEvent;
630
631 cpu->cycles = 0;
632 cpu->nextEvent = INT_MAX;
633
634 nextEvent = cycles;
635 do {
636 nextEvent = mTimingTick(&gb->timing, nextEvent);
637 } while (gb->cpuBlocked);
638 cpu->nextEvent = nextEvent;
639
640 if (gb->earlyExit) {
641 gb->earlyExit = false;
642 break;
643 }
644 if (cpu->halted) {
645 cpu->cycles = cpu->nextEvent;
646 if (!gb->memory.ie || !gb->memory.ime) {
647 break;
648 }
649 }
650 } while (cpu->cycles >= cpu->nextEvent);
651}
652
653void GBSetInterrupts(struct LR35902Core* cpu, bool enable) {
654 struct GB* gb = (struct GB*) cpu->master;
655 if (!enable) {
656 gb->memory.ime = enable;
657 mTimingDeschedule(&gb->timing, &gb->eiPending);
658 GBUpdateIRQs(gb);
659 } else {
660 mTimingDeschedule(&gb->timing, &gb->eiPending);
661 mTimingSchedule(&gb->timing, &gb->eiPending, 4);
662 }
663}
664
665uint16_t GBIRQVector(struct LR35902Core* cpu) {
666 struct GB* gb = (struct GB*) cpu->master;
667 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
668
669 if (irqs & (1 << GB_IRQ_VBLANK)) {
670 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_VBLANK);
671 return GB_VECTOR_VBLANK;
672 }
673 if (irqs & (1 << GB_IRQ_LCDSTAT)) {
674 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_LCDSTAT);
675 return GB_VECTOR_LCDSTAT;
676 }
677 if (irqs & (1 << GB_IRQ_TIMER)) {
678 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_TIMER);
679 return GB_VECTOR_TIMER;
680 }
681 if (irqs & (1 << GB_IRQ_SIO)) {
682 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_SIO);
683 return GB_VECTOR_SIO;
684 }
685 if (irqs & (1 << GB_IRQ_KEYPAD)) {
686 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_KEYPAD);
687 return GB_VECTOR_KEYPAD;
688 }
689 return 0;
690}
691
692static void _enableInterrupts(struct mTiming* timing, void* user, uint32_t cyclesLate) {
693 UNUSED(timing);
694 UNUSED(cyclesLate);
695 struct GB* gb = user;
696 gb->memory.ime = true;
697 GBUpdateIRQs(gb);
698}
699
700void GBHalt(struct LR35902Core* cpu) {
701 struct GB* gb = (struct GB*) cpu->master;
702 if (!(gb->memory.ie & gb->memory.io[REG_IF])) {
703 cpu->cycles = cpu->nextEvent;
704 cpu->halted = true;
705 } else if (gb->model < GB_MODEL_CGB) {
706 mLOG(GB, STUB, "Unimplemented HALT bug");
707 }
708}
709
710void GBStop(struct LR35902Core* cpu) {
711 struct GB* gb = (struct GB*) cpu->master;
712 if (cpu->bus) {
713 mLOG(GB, GAME_ERROR, "Hit illegal stop at address %04X:%02X", cpu->pc, cpu->bus);
714 }
715 if (gb->memory.io[REG_KEY1] & 1) {
716 gb->doubleSpeed ^= 1;
717 gb->audio.timingFactor = gb->doubleSpeed + 1;
718 gb->memory.io[REG_KEY1] = 0;
719 gb->memory.io[REG_KEY1] |= gb->doubleSpeed << 7;
720 } else if (cpu->bus) {
721#ifdef USE_DEBUGGERS
722 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
723 struct mDebuggerEntryInfo info = {
724 .address = cpu->pc - 1,
725 .type.bp.opcode = 0x1000 | cpu->bus
726 };
727 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
728 }
729#endif
730 // Hang forever
731 gb->memory.ime = 0;
732 cpu->pc -= 2;
733 }
734 // TODO: Actually stop
735}
736
737void GBIllegal(struct LR35902Core* cpu) {
738 struct GB* gb = (struct GB*) cpu->master;
739 mLOG(GB, GAME_ERROR, "Hit illegal opcode at address %04X:%02X", cpu->pc, cpu->bus);
740#ifdef USE_DEBUGGERS
741 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
742 struct mDebuggerEntryInfo info = {
743 .address = cpu->pc,
744 .type.bp.opcode = cpu->bus
745 };
746 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
747 }
748#endif
749 // Hang forever
750 gb->memory.ime = 0;
751 --cpu->pc;
752}
753
754bool GBIsROM(struct VFile* vf) {
755 if (!vf) {
756 return false;
757 }
758 vf->seek(vf, 0x104, SEEK_SET);
759 uint8_t header[4];
760
761 if (vf->read(vf, &header, sizeof(header)) < (ssize_t) sizeof(header)) {
762 return false;
763 }
764 if (memcmp(header, _knownHeader, sizeof(header))) {
765 return false;
766 }
767 return true;
768}
769
770void GBGetGameTitle(const struct GB* gb, char* out) {
771 const struct GBCartridge* cart = NULL;
772 if (gb->memory.rom) {
773 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
774 }
775 if (!cart) {
776 return;
777 }
778 if (cart->oldLicensee != 0x33) {
779 memcpy(out, cart->titleLong, 16);
780 } else {
781 memcpy(out, cart->titleShort, 11);
782 }
783}
784
785void GBGetGameCode(const struct GB* gb, char* out) {
786 memset(out, 0, 8);
787 const struct GBCartridge* cart = NULL;
788 if (gb->memory.rom) {
789 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
790 }
791 if (!cart) {
792 return;
793 }
794 if (cart->cgb == 0xC0) {
795 memcpy(out, "CGB-????", 8);
796 } else {
797 memcpy(out, "DMG-????", 8);
798 }
799 if (cart->oldLicensee == 0x33) {
800 memcpy(&out[4], cart->maker, 4);
801 }
802}
803
804void GBFrameEnded(struct GB* gb) {
805 GBSramClean(gb, gb->video.frameCounter);
806
807 if (gb->cpu->components && gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE]) {
808 struct mCheatDevice* device = (struct mCheatDevice*) gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE];
809 size_t i;
810 for (i = 0; i < mCheatSetsSize(&device->cheats); ++i) {
811 struct mCheatSet* cheats = *mCheatSetsGetPointer(&device->cheats, i);
812 mCheatRefresh(device, cheats);
813 }
814 }
815
816 GBTestKeypadIRQ(gb);
817}
818
819enum GBModel GBNameToModel(const char* model) {
820 if (strcasecmp(model, "DMG") == 0) {
821 return GB_MODEL_DMG;
822 } else if (strcasecmp(model, "CGB") == 0) {
823 return GB_MODEL_CGB;
824 } else if (strcasecmp(model, "AGB") == 0) {
825 return GB_MODEL_AGB;
826 } else if (strcasecmp(model, "SGB") == 0) {
827 return GB_MODEL_SGB;
828 } else if (strcasecmp(model, "MGB") == 0) {
829 return GB_MODEL_MGB;
830 } else if (strcasecmp(model, "SGB2") == 0) {
831 return GB_MODEL_SGB2;
832 }
833 return GB_MODEL_AUTODETECT;
834}
835
836const char* GBModelToName(enum GBModel model) {
837 switch (model) {
838 case GB_MODEL_DMG:
839 return "DMG";
840 case GB_MODEL_SGB:
841 return "SGB";
842 case GB_MODEL_MGB:
843 return "MGB";
844 case GB_MODEL_SGB2:
845 return "SGB2";
846 case GB_MODEL_CGB:
847 return "CGB";
848 case GB_MODEL_AGB:
849 return "AGB";
850 default:
851 case GB_MODEL_AUTODETECT:
852 return NULL;
853 }
854}