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->sgbControllers = 0;
450 gb->sgbCurrentController = 0;
451 gb->currentSgbBits = 0;
452 memset(gb->sgbPacket, 0, sizeof(gb->sgbPacket));
453
454 mTimingClear(&gb->timing);
455
456 GBMemoryReset(gb);
457 GBVideoReset(&gb->video);
458 GBTimerReset(&gb->timer);
459 if (!gb->biosVf) {
460 GBSkipBIOS(gb);
461 } else {
462 mTimingSchedule(&gb->timing, &gb->timer.event, 0);
463 }
464
465 GBIOReset(gb);
466 GBAudioReset(&gb->audio);
467 GBSIOReset(&gb->sio);
468
469 cpu->memory.setActiveRegion(cpu, cpu->pc);
470
471 GBSavedataUnmask(gb);
472}
473
474void GBSkipBIOS(struct GB* gb) {
475 struct LR35902Core* cpu = gb->cpu;
476 int nextDiv = 0;
477
478 switch (gb->model) {
479 case GB_MODEL_AUTODETECT: // Silence warnings
480 gb->model = GB_MODEL_DMG;
481 case GB_MODEL_DMG:
482 cpu->a = 1;
483 cpu->f.packed = 0xB0;
484 cpu->c = 0x13;
485 cpu->e = 0xD8;
486 cpu->h = 1;
487 cpu->l = 0x4D;
488 gb->timer.internalDiv = 0xABC;
489 nextDiv = 4;
490 break;
491 case GB_MODEL_SGB:
492 cpu->a = 1;
493 cpu->f.packed = 0x00;
494 cpu->c = 0x14;
495 cpu->e = 0x00;
496 cpu->h = 0xC0;
497 cpu->l = 0x60;
498 gb->timer.internalDiv = 0xABC;
499 nextDiv = 4;
500 break;
501 case GB_MODEL_MGB:
502 cpu->a = 0xFF;
503 cpu->f.packed = 0xB0;
504 cpu->c = 0x13;
505 cpu->e = 0xD8;
506 cpu->h = 1;
507 cpu->l = 0x4D;
508 gb->timer.internalDiv = 0xABC;
509 nextDiv = 4;
510 break;
511 case GB_MODEL_SGB2:
512 cpu->a = 0xFF;
513 cpu->f.packed = 0x00;
514 cpu->c = 0x14;
515 cpu->e = 0x00;
516 cpu->h = 0xC0;
517 cpu->l = 0x60;
518 gb->timer.internalDiv = 0xABC;
519 nextDiv = 4;
520 break;
521 case GB_MODEL_AGB:
522 cpu->a = 0x11;
523 cpu->b = 1;
524 cpu->f.packed = 0x00;
525 cpu->c = 0;
526 cpu->e = 0x08;
527 cpu->h = 0;
528 cpu->l = 0x7C;
529 gb->timer.internalDiv = 0x1EA;
530 nextDiv = 0xC;
531 break;
532 case GB_MODEL_CGB:
533 cpu->a = 0x11;
534 cpu->f.packed = 0x80;
535 cpu->c = 0;
536 cpu->e = 0x08;
537 cpu->h = 0;
538 cpu->l = 0x7C;
539 gb->timer.internalDiv = 0x1EA;
540 nextDiv = 0xC;
541 break;
542 }
543
544 cpu->sp = 0xFFFE;
545 cpu->pc = 0x100;
546
547 mTimingDeschedule(&gb->timing, &gb->timer.event);
548 mTimingSchedule(&gb->timing, &gb->timer.event, 0);
549
550 GBIOWrite(gb, REG_LCDC, 0x91);
551
552 if (gb->biosVf) {
553 GBUnmapBIOS(gb);
554 }
555}
556
557void GBUnmapBIOS(struct GB* gb) {
558 if (gb->memory.romBase < gb->memory.rom || gb->memory.romBase > &gb->memory.rom[gb->memory.romSize - 1]) {
559 free(gb->memory.romBase);
560 gb->memory.romBase = gb->memory.rom;
561 }
562 // XXX: Force AGB registers for AGB-mode
563 if (gb->model == GB_MODEL_AGB && gb->cpu->pc == 0x100) {
564 gb->cpu->b = 1;
565 }
566}
567
568void GBDetectModel(struct GB* gb) {
569 if (gb->model != GB_MODEL_AUTODETECT) {
570 return;
571 }
572 if (gb->biosVf) {
573 switch (_GBBiosCRC32(gb->biosVf)) {
574 case DMG_BIOS_CHECKSUM:
575 case DMG_2_BIOS_CHECKSUM:
576 gb->model = GB_MODEL_DMG;
577 break;
578 case MGB_BIOS_CHECKSUM:
579 gb->model = GB_MODEL_MGB;
580 break;
581 case SGB_BIOS_CHECKSUM:
582 gb->model = GB_MODEL_SGB;
583 break;
584 case CGB_BIOS_CHECKSUM:
585 gb->model = GB_MODEL_CGB;
586 break;
587 default:
588 gb->biosVf->close(gb->biosVf);
589 gb->biosVf = NULL;
590 }
591 }
592 if (gb->model == GB_MODEL_AUTODETECT && gb->memory.rom) {
593 const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
594 if (cart->cgb & 0x80) {
595 gb->model = GB_MODEL_CGB;
596 } else if (cart->sgb == 0x03 && cart->oldLicensee == 0x33) {
597 gb->model = GB_MODEL_SGB;
598 } else {
599 gb->model = GB_MODEL_DMG;
600 }
601 }
602
603 switch (gb->model) {
604 case GB_MODEL_DMG:
605 case GB_MODEL_SGB:
606 case GB_MODEL_AUTODETECT: //Silence warnings
607 gb->audio.style = GB_AUDIO_DMG;
608 break;
609 case GB_MODEL_MGB:
610 case GB_MODEL_SGB2:
611 gb->audio.style = GB_AUDIO_MGB;
612 break;
613 case GB_MODEL_AGB:
614 case GB_MODEL_CGB:
615 gb->audio.style = GB_AUDIO_CGB;
616 break;
617 }
618}
619
620void GBUpdateIRQs(struct GB* gb) {
621 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
622 if (!irqs) {
623 gb->cpu->irqPending = false;
624 return;
625 }
626 gb->cpu->halted = false;
627
628 if (!gb->memory.ime || gb->cpu->irqPending) {
629 return;
630 }
631 LR35902RaiseIRQ(gb->cpu);
632}
633
634void GBProcessEvents(struct LR35902Core* cpu) {
635 struct GB* gb = (struct GB*) cpu->master;
636 do {
637 int32_t cycles = cpu->cycles;
638 int32_t nextEvent;
639
640 cpu->cycles = 0;
641 cpu->nextEvent = INT_MAX;
642
643 nextEvent = cycles;
644 do {
645 nextEvent = mTimingTick(&gb->timing, nextEvent);
646 } while (gb->cpuBlocked);
647 cpu->nextEvent = nextEvent;
648
649 if (cpu->halted) {
650 cpu->cycles = cpu->nextEvent;
651 if (!gb->memory.ie || !gb->memory.ime) {
652 break;
653 }
654 }
655 if (gb->earlyExit) {
656 break;
657 }
658 } while (cpu->cycles >= cpu->nextEvent);
659 gb->earlyExit = false;
660}
661
662void GBSetInterrupts(struct LR35902Core* cpu, bool enable) {
663 struct GB* gb = (struct GB*) cpu->master;
664 if (!enable) {
665 gb->memory.ime = enable;
666 mTimingDeschedule(&gb->timing, &gb->eiPending);
667 GBUpdateIRQs(gb);
668 } else {
669 mTimingDeschedule(&gb->timing, &gb->eiPending);
670 mTimingSchedule(&gb->timing, &gb->eiPending, 4);
671 }
672}
673
674uint16_t GBIRQVector(struct LR35902Core* cpu) {
675 struct GB* gb = (struct GB*) cpu->master;
676 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
677
678 if (irqs & (1 << GB_IRQ_VBLANK)) {
679 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_VBLANK);
680 return GB_VECTOR_VBLANK;
681 }
682 if (irqs & (1 << GB_IRQ_LCDSTAT)) {
683 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_LCDSTAT);
684 return GB_VECTOR_LCDSTAT;
685 }
686 if (irqs & (1 << GB_IRQ_TIMER)) {
687 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_TIMER);
688 return GB_VECTOR_TIMER;
689 }
690 if (irqs & (1 << GB_IRQ_SIO)) {
691 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_SIO);
692 return GB_VECTOR_SIO;
693 }
694 if (irqs & (1 << GB_IRQ_KEYPAD)) {
695 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_KEYPAD);
696 return GB_VECTOR_KEYPAD;
697 }
698 return 0;
699}
700
701static void _enableInterrupts(struct mTiming* timing, void* user, uint32_t cyclesLate) {
702 UNUSED(timing);
703 UNUSED(cyclesLate);
704 struct GB* gb = user;
705 gb->memory.ime = true;
706 GBUpdateIRQs(gb);
707}
708
709void GBHalt(struct LR35902Core* cpu) {
710 struct GB* gb = (struct GB*) cpu->master;
711 if (!(gb->memory.ie & gb->memory.io[REG_IF])) {
712 cpu->cycles = cpu->nextEvent;
713 cpu->halted = true;
714 } else if (gb->model < GB_MODEL_CGB) {
715 mLOG(GB, STUB, "Unimplemented HALT bug");
716 }
717}
718
719void GBStop(struct LR35902Core* cpu) {
720 struct GB* gb = (struct GB*) cpu->master;
721 if (cpu->bus) {
722 mLOG(GB, GAME_ERROR, "Hit illegal stop at address %04X:%02X", cpu->pc, cpu->bus);
723 }
724 if (gb->memory.io[REG_KEY1] & 1) {
725 gb->doubleSpeed ^= 1;
726 gb->audio.timingFactor = gb->doubleSpeed + 1;
727 gb->memory.io[REG_KEY1] = 0;
728 gb->memory.io[REG_KEY1] |= gb->doubleSpeed << 7;
729 } else if (cpu->bus) {
730#ifdef USE_DEBUGGERS
731 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
732 struct mDebuggerEntryInfo info = {
733 .address = cpu->pc - 1,
734 .type.bp.opcode = 0x1000 | cpu->bus
735 };
736 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
737 }
738#endif
739 // Hang forever
740 gb->memory.ime = 0;
741 cpu->pc -= 2;
742 }
743 // TODO: Actually stop
744}
745
746void GBIllegal(struct LR35902Core* cpu) {
747 struct GB* gb = (struct GB*) cpu->master;
748 mLOG(GB, GAME_ERROR, "Hit illegal opcode at address %04X:%02X", cpu->pc, cpu->bus);
749#ifdef USE_DEBUGGERS
750 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
751 struct mDebuggerEntryInfo info = {
752 .address = cpu->pc,
753 .type.bp.opcode = cpu->bus
754 };
755 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
756 }
757#endif
758 // Hang forever
759 gb->memory.ime = 0;
760 --cpu->pc;
761}
762
763bool GBIsROM(struct VFile* vf) {
764 if (!vf) {
765 return false;
766 }
767 vf->seek(vf, 0x104, SEEK_SET);
768 uint8_t header[4];
769
770 if (vf->read(vf, &header, sizeof(header)) < (ssize_t) sizeof(header)) {
771 return false;
772 }
773 if (memcmp(header, _knownHeader, sizeof(header))) {
774 return false;
775 }
776 return true;
777}
778
779void GBGetGameTitle(const struct GB* gb, char* out) {
780 const struct GBCartridge* cart = NULL;
781 if (gb->memory.rom) {
782 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
783 }
784 if (!cart) {
785 return;
786 }
787 if (cart->oldLicensee != 0x33) {
788 memcpy(out, cart->titleLong, 16);
789 } else {
790 memcpy(out, cart->titleShort, 11);
791 }
792}
793
794void GBGetGameCode(const struct GB* gb, char* out) {
795 memset(out, 0, 8);
796 const struct GBCartridge* cart = NULL;
797 if (gb->memory.rom) {
798 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
799 }
800 if (!cart) {
801 return;
802 }
803 if (cart->cgb == 0xC0) {
804 memcpy(out, "CGB-????", 8);
805 } else {
806 memcpy(out, "DMG-????", 8);
807 }
808 if (cart->oldLicensee == 0x33) {
809 memcpy(&out[4], cart->maker, 4);
810 }
811}
812
813void GBFrameEnded(struct GB* gb) {
814 GBSramClean(gb, gb->video.frameCounter);
815
816 if (gb->cpu->components && gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE]) {
817 struct mCheatDevice* device = (struct mCheatDevice*) gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE];
818 size_t i;
819 for (i = 0; i < mCheatSetsSize(&device->cheats); ++i) {
820 struct mCheatSet* cheats = *mCheatSetsGetPointer(&device->cheats, i);
821 mCheatRefresh(device, cheats);
822 }
823 }
824
825 GBTestKeypadIRQ(gb);
826}
827
828enum GBModel GBNameToModel(const char* model) {
829 if (strcasecmp(model, "DMG") == 0) {
830 return GB_MODEL_DMG;
831 } else if (strcasecmp(model, "CGB") == 0) {
832 return GB_MODEL_CGB;
833 } else if (strcasecmp(model, "AGB") == 0) {
834 return GB_MODEL_AGB;
835 } else if (strcasecmp(model, "SGB") == 0) {
836 return GB_MODEL_SGB;
837 } else if (strcasecmp(model, "MGB") == 0) {
838 return GB_MODEL_MGB;
839 } else if (strcasecmp(model, "SGB2") == 0) {
840 return GB_MODEL_SGB2;
841 }
842 return GB_MODEL_AUTODETECT;
843}
844
845const char* GBModelToName(enum GBModel model) {
846 switch (model) {
847 case GB_MODEL_DMG:
848 return "DMG";
849 case GB_MODEL_SGB:
850 return "SGB";
851 case GB_MODEL_MGB:
852 return "MGB";
853 case GB_MODEL_SGB2:
854 return "SGB2";
855 case GB_MODEL_CGB:
856 return "CGB";
857 case GB_MODEL_AGB:
858 return "AGB";
859 default:
860 case GB_MODEL_AUTODETECT:
861 return NULL;
862 }
863}