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