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 SGB_BIOS_CHECKSUM 0xEC8A83B9
32#define CGB_BIOS_CHECKSUM 0x41884E46
33
34mLOG_DEFINE_CATEGORY(GB, "GB", "gb");
35
36static void GBInit(void* cpu, struct mCPUComponent* component);
37static void GBDeinit(struct mCPUComponent* component);
38static void GBInterruptHandlerInit(struct LR35902InterruptHandler* irqh);
39static void GBProcessEvents(struct LR35902Core* cpu);
40static void GBSetInterrupts(struct LR35902Core* cpu, bool enable);
41static void GBIllegal(struct LR35902Core* cpu);
42static void GBStop(struct LR35902Core* cpu);
43
44static void _enableInterrupts(struct mTiming* timing, void* user, uint32_t cyclesLate);
45
46#ifdef FIXED_ROM_BUFFER
47extern uint32_t* romBuffer;
48extern size_t romBufferSize;
49#endif
50
51void GBCreate(struct GB* gb) {
52 gb->d.id = GB_COMPONENT_MAGIC;
53 gb->d.init = GBInit;
54 gb->d.deinit = GBDeinit;
55}
56
57static void GBInit(void* cpu, struct mCPUComponent* component) {
58 struct GB* gb = (struct GB*) component;
59 gb->cpu = cpu;
60 gb->sync = NULL;
61
62 GBInterruptHandlerInit(&gb->cpu->irqh);
63 GBMemoryInit(gb);
64
65 gb->video.p = gb;
66 GBVideoInit(&gb->video);
67
68 gb->audio.p = gb;
69 GBAudioInit(&gb->audio, 2048, &gb->memory.io[REG_NR52], GB_AUDIO_DMG); // TODO: Remove magic constant
70
71 gb->sio.p = gb;
72 GBSIOInit(&gb->sio);
73
74 gb->timer.p = gb;
75
76 gb->model = GB_MODEL_AUTODETECT;
77
78 gb->biosVf = NULL;
79 gb->romVf = NULL;
80 gb->sramVf = NULL;
81 gb->sramRealVf = NULL;
82
83 gb->isPristine = false;
84 gb->pristineRomSize = 0;
85 gb->yankedRomSize = 0;
86
87 mCoreCallbacksListInit(&gb->coreCallbacks, 0);
88 gb->stream = NULL;
89
90 mTimingInit(&gb->timing, &gb->cpu->cycles, &gb->cpu->nextEvent);
91 gb->audio.timing = &gb->timing;
92
93 gb->eiPending.name = "GB EI";
94 gb->eiPending.callback = _enableInterrupts;
95 gb->eiPending.context = gb;
96 gb->eiPending.priority = 0;
97}
98
99static void GBDeinit(struct mCPUComponent* component) {
100 struct GB* gb = (struct GB*) component;
101 mTimingDeinit(&gb->timing);
102}
103
104bool GBLoadROM(struct GB* gb, struct VFile* vf) {
105 if (!vf) {
106 return false;
107 }
108 GBUnloadROM(gb);
109 gb->romVf = vf;
110 gb->pristineRomSize = vf->size(vf);
111 vf->seek(vf, 0, SEEK_SET);
112 gb->isPristine = true;
113#ifdef FIXED_ROM_BUFFER
114 if (gb->pristineRomSize <= romBufferSize) {
115 gb->memory.rom = romBuffer;
116 vf->read(vf, romBuffer, gb->pristineRomSize);
117 }
118#else
119 gb->memory.rom = vf->map(vf, gb->pristineRomSize, MAP_READ);
120#endif
121 if (!gb->memory.rom) {
122 return false;
123 }
124 gb->yankedRomSize = 0;
125 gb->memory.romBase = gb->memory.rom;
126 gb->memory.romSize = gb->pristineRomSize;
127 gb->romCrc32 = doCrc32(gb->memory.rom, gb->memory.romSize);
128 GBMBCInit(gb);
129
130 if (gb->cpu) {
131 struct LR35902Core* cpu = gb->cpu;
132 cpu->memory.setActiveRegion(cpu, cpu->pc);
133 }
134
135 // TODO: error check
136 return true;
137}
138
139static void GBSramDeinit(struct GB* gb) {
140 if (gb->sramVf) {
141 gb->sramVf->unmap(gb->sramVf, gb->memory.sram, gb->sramSize);
142 if (gb->memory.mbcType == GB_MBC3_RTC && gb->sramVf == gb->sramRealVf) {
143 GBMBCRTCWrite(gb);
144 }
145 gb->sramVf = NULL;
146 } else if (gb->memory.sram) {
147 mappedMemoryFree(gb->memory.sram, gb->sramSize);
148 }
149 gb->memory.sram = 0;
150}
151
152bool GBLoadSave(struct GB* gb, struct VFile* vf) {
153 GBSramDeinit(gb);
154 gb->sramVf = vf;
155 gb->sramRealVf = vf;
156 if (gb->sramSize) {
157 GBResizeSram(gb, gb->sramSize);
158 }
159 return vf;
160}
161
162void GBResizeSram(struct GB* gb, size_t size) {
163 if (gb->memory.sram && size <= gb->sramSize) {
164 return;
165 }
166 struct VFile* vf = gb->sramVf;
167 if (vf) {
168 if (vf == gb->sramRealVf) {
169 ssize_t vfSize = vf->size(vf);
170 if (vfSize >= 0 && (size_t) vfSize < size) {
171 uint8_t extdataBuffer[0x100];
172 if (vfSize & 0xFF) {
173 vf->seek(vf, -(vfSize & 0xFF), SEEK_END);
174 vf->read(vf, extdataBuffer, vfSize & 0xFF);
175 }
176 if (gb->memory.sram) {
177 vf->unmap(vf, gb->memory.sram, gb->sramSize);
178 }
179 vf->truncate(vf, size + (vfSize & 0xFF));
180 if (vfSize & 0xFF) {
181 vf->seek(vf, size, SEEK_SET);
182 vf->write(vf, extdataBuffer, vfSize & 0xFF);
183 }
184 gb->memory.sram = vf->map(vf, size, MAP_WRITE);
185 memset(&gb->memory.sram[gb->sramSize], 0xFF, size - gb->sramSize);
186 } else if (size > gb->sramSize || !gb->memory.sram) {
187 if (gb->memory.sram) {
188 vf->unmap(vf, gb->memory.sram, gb->sramSize);
189 }
190 gb->memory.sram = vf->map(vf, size, MAP_WRITE);
191 }
192 } else {
193 if (gb->memory.sram) {
194 vf->unmap(vf, gb->memory.sram, gb->sramSize);
195 }
196 gb->memory.sram = vf->map(vf, size, MAP_READ);
197 }
198 if (gb->memory.sram == (void*) -1) {
199 gb->memory.sram = NULL;
200 }
201 } else {
202 uint8_t* newSram = anonymousMemoryMap(size);
203 if (gb->memory.sram) {
204 if (size > gb->sramSize) {
205 memcpy(newSram, gb->memory.sram, gb->sramSize);
206 memset(&newSram[gb->sramSize], 0xFF, size - gb->sramSize);
207 } else {
208 memcpy(newSram, gb->memory.sram, size);
209 }
210 mappedMemoryFree(gb->memory.sram, gb->sramSize);
211 } else {
212 memset(newSram, 0xFF, size);
213 }
214 gb->memory.sram = newSram;
215 }
216 if (gb->sramSize < size) {
217 gb->sramSize = size;
218 }
219}
220
221void GBSramClean(struct GB* gb, uint32_t frameCount) {
222 // TODO: Share with GBASavedataClean
223 if (!gb->sramVf) {
224 return;
225 }
226 if (gb->sramDirty & GB_SRAM_DIRT_NEW) {
227 gb->sramDirtAge = frameCount;
228 gb->sramDirty &= ~GB_SRAM_DIRT_NEW;
229 if (!(gb->sramDirty & GB_SRAM_DIRT_SEEN)) {
230 gb->sramDirty |= GB_SRAM_DIRT_SEEN;
231 }
232 } else if ((gb->sramDirty & GB_SRAM_DIRT_SEEN) && frameCount - gb->sramDirtAge > CLEANUP_THRESHOLD) {
233 if (gb->sramMaskWriteback) {
234 GBSavedataUnmask(gb);
235 }
236 if (gb->memory.mbcType == GB_MBC3_RTC) {
237 GBMBCRTCWrite(gb);
238 }
239 gb->sramDirty = 0;
240 if (gb->memory.sram && gb->sramVf->sync(gb->sramVf, gb->memory.sram, gb->sramSize)) {
241 mLOG(GB_MEM, INFO, "Savedata synced");
242 } else {
243 mLOG(GB_MEM, INFO, "Savedata failed to sync!");
244 }
245 }
246}
247
248void GBSavedataMask(struct GB* gb, struct VFile* vf, bool writeback) {
249 GBSramDeinit(gb);
250 gb->sramVf = vf;
251 gb->sramMaskWriteback = writeback;
252 gb->memory.sram = vf->map(vf, gb->sramSize, MAP_READ);
253 GBMBCSwitchSramBank(gb, gb->memory.sramCurrentBank);
254}
255
256void GBSavedataUnmask(struct GB* gb) {
257 if (gb->sramVf == gb->sramRealVf) {
258 return;
259 }
260 struct VFile* vf = gb->sramVf;
261 GBSramDeinit(gb);
262 gb->sramVf = gb->sramRealVf;
263 gb->memory.sram = gb->sramVf->map(gb->sramVf, gb->sramSize, MAP_WRITE);
264 if (gb->sramMaskWriteback) {
265 vf->seek(vf, 0, SEEK_SET);
266 vf->read(vf, gb->memory.sram, gb->sramSize);
267 gb->sramMaskWriteback = false;
268 }
269 vf->close(vf);
270}
271
272void GBUnloadROM(struct GB* gb) {
273 // TODO: Share with GBAUnloadROM
274 if (gb->memory.rom && gb->memory.romBase != gb->memory.rom && !gb->isPristine) {
275 free(gb->memory.romBase);
276 }
277 if (gb->memory.rom && !gb->isPristine) {
278 if (gb->yankedRomSize) {
279 gb->yankedRomSize = 0;
280 }
281 mappedMemoryFree(gb->memory.rom, GB_SIZE_CART_MAX);
282 }
283
284 if (gb->romVf) {
285#ifndef FIXED_ROM_BUFFER
286 gb->romVf->unmap(gb->romVf, gb->memory.rom, gb->pristineRomSize);
287#endif
288 gb->romVf->close(gb->romVf);
289 gb->romVf = NULL;
290 }
291 gb->memory.rom = NULL;
292 gb->memory.mbcType = GB_MBC_AUTODETECT;
293 gb->isPristine = false;
294
295 gb->sramMaskWriteback = false;
296 GBSavedataUnmask(gb);
297 GBSramDeinit(gb);
298 if (gb->sramRealVf) {
299 gb->sramRealVf->close(gb->sramRealVf);
300 }
301 gb->sramRealVf = NULL;
302 gb->sramVf = NULL;
303 if (gb->memory.cam && gb->memory.cam->stopRequestImage) {
304 gb->memory.cam->stopRequestImage(gb->memory.cam);
305 }
306}
307
308void GBSynthesizeROM(struct VFile* vf) {
309 if (!vf) {
310 return;
311 }
312 const struct GBCartridge cart = {
313 .logo = { _knownHeader[0], _knownHeader[1], _knownHeader[2], _knownHeader[3]}
314 };
315
316 vf->seek(vf, 0x100, SEEK_SET);
317 vf->write(vf, &cart, sizeof(cart));
318}
319
320void GBLoadBIOS(struct GB* gb, struct VFile* vf) {
321 gb->biosVf = vf;
322}
323
324void GBApplyPatch(struct GB* gb, struct Patch* patch) {
325 size_t patchedSize = patch->outputSize(patch, gb->memory.romSize);
326 if (!patchedSize) {
327 return;
328 }
329 if (patchedSize > GB_SIZE_CART_MAX) {
330 patchedSize = GB_SIZE_CART_MAX;
331 }
332 void* newRom = anonymousMemoryMap(GB_SIZE_CART_MAX);
333 if (!patch->applyPatch(patch, gb->memory.rom, gb->pristineRomSize, newRom, patchedSize)) {
334 mappedMemoryFree(newRom, GB_SIZE_CART_MAX);
335 return;
336 }
337 if (gb->romVf) {
338#ifndef FIXED_ROM_BUFFER
339 gb->romVf->unmap(gb->romVf, gb->memory.rom, gb->pristineRomSize);
340#endif
341 gb->romVf->close(gb->romVf);
342 gb->romVf = NULL;
343 }
344 gb->isPristine = false;
345 if (gb->memory.romBase == gb->memory.rom) {
346 gb->memory.romBase = newRom;
347 }
348 gb->memory.rom = newRom;
349 gb->memory.romSize = patchedSize;
350 gb->romCrc32 = doCrc32(gb->memory.rom, gb->memory.romSize);
351 gb->cpu->memory.setActiveRegion(gb->cpu, gb->cpu->pc);
352}
353
354void GBDestroy(struct GB* gb) {
355 GBUnloadROM(gb);
356
357 if (gb->biosVf) {
358 gb->biosVf->close(gb->biosVf);
359 gb->biosVf = 0;
360 }
361
362 GBMemoryDeinit(gb);
363 GBAudioDeinit(&gb->audio);
364 GBVideoDeinit(&gb->video);
365 GBSIODeinit(&gb->sio);
366 mCoreCallbacksListDeinit(&gb->coreCallbacks);
367}
368
369void GBInterruptHandlerInit(struct LR35902InterruptHandler* irqh) {
370 irqh->reset = GBReset;
371 irqh->processEvents = GBProcessEvents;
372 irqh->setInterrupts = GBSetInterrupts;
373 irqh->hitIllegal = GBIllegal;
374 irqh->stop = GBStop;
375 irqh->halt = GBHalt;
376}
377
378static uint32_t _GBBiosCRC32(struct VFile* vf) {
379 ssize_t size = vf->size(vf);
380 if (size <= 0 || size > GB_SIZE_CART_BANK0) {
381 return 0;
382 }
383 void* bios = vf->map(vf, size, MAP_READ);
384 uint32_t biosCrc = doCrc32(bios, size);
385 vf->unmap(vf, bios, size);
386 return biosCrc;
387}
388
389bool GBIsBIOS(struct VFile* vf) {
390 switch (_GBBiosCRC32(vf)) {
391 case DMG_BIOS_CHECKSUM:
392 case DMG_2_BIOS_CHECKSUM:
393 case SGB_BIOS_CHECKSUM:
394 case CGB_BIOS_CHECKSUM:
395 return true;
396 default:
397 return false;
398 }
399}
400
401void GBReset(struct LR35902Core* cpu) {
402 struct GB* gb = (struct GB*) cpu->master;
403 gb->memory.romBase = gb->memory.rom;
404 GBDetectModel(gb);
405
406 if (gb->biosVf) {
407 if (!GBIsBIOS(gb->biosVf)) {
408 gb->biosVf->close(gb->biosVf);
409 gb->biosVf = NULL;
410 } else {
411 gb->biosVf->seek(gb->biosVf, 0, SEEK_SET);
412 gb->memory.romBase = malloc(GB_SIZE_CART_BANK0);
413 ssize_t size = gb->biosVf->read(gb->biosVf, gb->memory.romBase, GB_SIZE_CART_BANK0);
414 memcpy(&gb->memory.romBase[size], &gb->memory.rom[size], GB_SIZE_CART_BANK0 - size);
415 if (size > 0x100) {
416 memcpy(&gb->memory.romBase[0x100], &gb->memory.rom[0x100], sizeof(struct GBCartridge));
417 }
418
419 cpu->a = 0;
420 cpu->f.packed = 0;
421 cpu->c = 0;
422 cpu->e = 0;
423 cpu->h = 0;
424 cpu->l = 0;
425 cpu->sp = 0;
426 cpu->pc = 0;
427 }
428 }
429
430 cpu->b = 0;
431 cpu->d = 0;
432
433 if (!gb->biosVf) {
434 switch (gb->model) {
435 case GB_MODEL_AUTODETECT: // Silence warnings
436 gb->model = GB_MODEL_DMG;
437 // TODO: SGB registers
438 case GB_MODEL_SGB:
439 case GB_MODEL_DMG:
440 cpu->a = 1;
441 cpu->f.packed = 0xB0;
442 cpu->c = 0x13;
443 cpu->e = 0xD8;
444 cpu->h = 1;
445 cpu->l = 0x4D;
446 gb->timer.internalDiv = 0x2AF3;
447 break;
448 case GB_MODEL_AGB:
449 cpu->b = 1;
450 // Fall through
451 case GB_MODEL_CGB:
452 cpu->a = 0x11;
453 cpu->f.packed = 0x80;
454 cpu->c = 0;
455 cpu->e = 0x08;
456 cpu->h = 0;
457 cpu->l = 0x7C;
458 gb->timer.internalDiv = 0x7A8;
459 break;
460 }
461
462 cpu->sp = 0xFFFE;
463 cpu->pc = 0x100;
464 }
465
466 gb->cpuBlocked = false;
467 gb->earlyExit = false;
468 gb->doubleSpeed = 0;
469
470 cpu->memory.setActiveRegion(cpu, cpu->pc);
471
472 if (gb->yankedRomSize) {
473 gb->memory.romSize = gb->yankedRomSize;
474 gb->yankedRomSize = 0;
475 }
476
477 gb->sgbBit = -1;
478 gb->currentSgbBits = 0;
479 memset(gb->sgbPacket, 0, sizeof(gb->sgbPacket));
480
481 mTimingClear(&gb->timing);
482
483 GBMemoryReset(gb);
484 GBVideoReset(&gb->video);
485 GBTimerReset(&gb->timer);
486 mTimingSchedule(&gb->timing, &gb->timer.event, GB_DMG_DIV_PERIOD);
487
488 GBAudioReset(&gb->audio);
489 GBIOReset(gb);
490 GBSIOReset(&gb->sio);
491
492 GBSavedataUnmask(gb);
493}
494
495void GBDetectModel(struct GB* gb) {
496 if (gb->model != GB_MODEL_AUTODETECT) {
497 return;
498 }
499 if (gb->biosVf) {
500 switch (_GBBiosCRC32(gb->biosVf)) {
501 case DMG_BIOS_CHECKSUM:
502 case DMG_2_BIOS_CHECKSUM:
503 gb->model = GB_MODEL_DMG;
504 break;
505 case SGB_BIOS_CHECKSUM:
506 gb->model = GB_MODEL_SGB;
507 break;
508 case CGB_BIOS_CHECKSUM:
509 gb->model = GB_MODEL_CGB;
510 break;
511 default:
512 gb->biosVf->close(gb->biosVf);
513 gb->biosVf = NULL;
514 }
515 }
516 if (gb->model == GB_MODEL_AUTODETECT && gb->memory.rom) {
517 const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
518 if (cart->cgb & 0x80) {
519 gb->model = GB_MODEL_CGB;
520 } else if (cart->sgb == 0x03 && cart->oldLicensee == 0x33) {
521 gb->model = GB_MODEL_SGB;
522 } else {
523 gb->model = GB_MODEL_DMG;
524 }
525 }
526
527 switch (gb->model) {
528 case GB_MODEL_DMG:
529 case GB_MODEL_SGB:
530 case GB_MODEL_AUTODETECT: //Silence warnings
531 gb->audio.style = GB_AUDIO_DMG;
532 break;
533 case GB_MODEL_AGB:
534 case GB_MODEL_CGB:
535 gb->audio.style = GB_AUDIO_CGB;
536 break;
537 }
538}
539
540void GBUpdateIRQs(struct GB* gb) {
541 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
542 if (!irqs) {
543 return;
544 }
545 gb->cpu->halted = false;
546
547 if (!gb->memory.ime || gb->cpu->irqPending) {
548 return;
549 }
550
551 if (irqs & (1 << GB_IRQ_VBLANK)) {
552 LR35902RaiseIRQ(gb->cpu, GB_VECTOR_VBLANK);
553 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_VBLANK);
554 return;
555 }
556 if (irqs & (1 << GB_IRQ_LCDSTAT)) {
557 LR35902RaiseIRQ(gb->cpu, GB_VECTOR_LCDSTAT);
558 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_LCDSTAT);
559 return;
560 }
561 if (irqs & (1 << GB_IRQ_TIMER)) {
562 LR35902RaiseIRQ(gb->cpu, GB_VECTOR_TIMER);
563 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_TIMER);
564 return;
565 }
566 if (irqs & (1 << GB_IRQ_SIO)) {
567 LR35902RaiseIRQ(gb->cpu, GB_VECTOR_SIO);
568 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_SIO);
569 return;
570 }
571 if (irqs & (1 << GB_IRQ_KEYPAD)) {
572 LR35902RaiseIRQ(gb->cpu, GB_VECTOR_KEYPAD);
573 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_KEYPAD);
574 }
575}
576
577void GBProcessEvents(struct LR35902Core* cpu) {
578 struct GB* gb = (struct GB*) cpu->master;
579 do {
580 int32_t cycles = cpu->cycles;
581 int32_t nextEvent;
582
583 cpu->cycles = 0;
584 cpu->nextEvent = INT_MAX;
585
586 nextEvent = cycles;
587 do {
588 nextEvent = mTimingTick(&gb->timing, nextEvent);
589 } while (gb->cpuBlocked);
590 cpu->nextEvent = nextEvent;
591
592 if (gb->earlyExit) {
593 gb->earlyExit = false;
594 break;
595 }
596 if (cpu->halted) {
597 cpu->cycles = cpu->nextEvent;
598 if (!gb->memory.ie || !gb->memory.ime) {
599 break;
600 }
601 }
602 } while (cpu->cycles >= cpu->nextEvent);
603}
604
605void GBSetInterrupts(struct LR35902Core* cpu, bool enable) {
606 struct GB* gb = (struct GB*) cpu->master;
607 if (!enable) {
608 gb->memory.ime = enable;
609 mTimingDeschedule(&gb->timing, &gb->eiPending);
610 GBUpdateIRQs(gb);
611 } else {
612 mTimingDeschedule(&gb->timing, &gb->eiPending);
613 mTimingSchedule(&gb->timing, &gb->eiPending, 4);
614 }
615}
616
617static void _enableInterrupts(struct mTiming* timing, void* user, uint32_t cyclesLate) {
618 UNUSED(timing);
619 UNUSED(cyclesLate);
620 struct GB* gb = user;
621 gb->memory.ime = true;
622 GBUpdateIRQs(gb);
623}
624
625void GBHalt(struct LR35902Core* cpu) {
626 if (!cpu->irqPending) {
627 cpu->cycles = cpu->nextEvent;
628 cpu->halted = true;
629 }
630}
631
632void GBStop(struct LR35902Core* cpu) {
633 struct GB* gb = (struct GB*) cpu->master;
634 if (cpu->bus) {
635 mLOG(GB, GAME_ERROR, "Hit illegal stop at address %04X:%02X", cpu->pc, cpu->bus);
636 }
637 if (gb->memory.io[REG_KEY1] & 1) {
638 gb->doubleSpeed ^= 1;
639 gb->audio.timingFactor = gb->doubleSpeed + 1;
640 gb->memory.io[REG_KEY1] = 0;
641 gb->memory.io[REG_KEY1] |= gb->doubleSpeed << 7;
642 } else if (cpu->bus) {
643#ifdef USE_DEBUGGERS
644 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
645 struct mDebuggerEntryInfo info = {
646 .address = cpu->pc - 1,
647 .opcode = 0x1000 | cpu->bus
648 };
649 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
650 }
651#endif
652 // Hang forever
653 gb->memory.ime = 0;
654 cpu->pc -= 2;
655 }
656 // TODO: Actually stop
657}
658
659void GBIllegal(struct LR35902Core* cpu) {
660 struct GB* gb = (struct GB*) cpu->master;
661 mLOG(GB, GAME_ERROR, "Hit illegal opcode at address %04X:%02X", cpu->pc, cpu->bus);
662#ifdef USE_DEBUGGERS
663 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
664 struct mDebuggerEntryInfo info = {
665 .address = cpu->pc,
666 .opcode = cpu->bus
667 };
668 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
669 }
670#endif
671 // Hang forever
672 gb->memory.ime = 0;
673 --cpu->pc;
674}
675
676bool GBIsROM(struct VFile* vf) {
677 if (!vf) {
678 return false;
679 }
680 vf->seek(vf, 0x104, SEEK_SET);
681 uint8_t header[4];
682
683 if (vf->read(vf, &header, sizeof(header)) < (ssize_t) sizeof(header)) {
684 return false;
685 }
686 if (memcmp(header, _knownHeader, sizeof(header))) {
687 return false;
688 }
689 return true;
690}
691
692void GBGetGameTitle(const struct GB* gb, char* out) {
693 const struct GBCartridge* cart = NULL;
694 if (gb->memory.rom) {
695 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
696 }
697 if (!cart) {
698 return;
699 }
700 if (cart->oldLicensee != 0x33) {
701 memcpy(out, cart->titleLong, 16);
702 } else {
703 memcpy(out, cart->titleShort, 11);
704 }
705}
706
707void GBGetGameCode(const struct GB* gb, char* out) {
708 memset(out, 0, 8);
709 const struct GBCartridge* cart = NULL;
710 if (gb->memory.rom) {
711 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
712 }
713 if (!cart) {
714 return;
715 }
716 if (cart->cgb == 0xC0) {
717 memcpy(out, "CGB-????", 8);
718 } else {
719 memcpy(out, "DMG-????", 8);
720 }
721 if (cart->oldLicensee == 0x33) {
722 memcpy(&out[4], cart->maker, 4);
723 }
724}
725
726void GBFrameEnded(struct GB* gb) {
727 GBSramClean(gb, gb->video.frameCounter);
728
729 if (gb->cpu->components && gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE]) {
730 struct mCheatDevice* device = (struct mCheatDevice*) gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE];
731 size_t i;
732 for (i = 0; i < mCheatSetsSize(&device->cheats); ++i) {
733 struct mCheatSet* cheats = *mCheatSetsGetPointer(&device->cheats, i);
734 mCheatRefresh(device, cheats);
735 }
736 }
737
738 GBTestKeypadIRQ(gb);
739}