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->sramRealVf || 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 GBSramDeinit(gb);
299 if (gb->sramRealVf) {
300 gb->sramRealVf->close(gb->sramRealVf);
301 }
302 gb->sramRealVf = NULL;
303 gb->sramVf = NULL;
304 if (gb->memory.cam && gb->memory.cam->stopRequestImage) {
305 gb->memory.cam->stopRequestImage(gb->memory.cam);
306 }
307}
308
309void GBSynthesizeROM(struct VFile* vf) {
310 if (!vf) {
311 return;
312 }
313 const struct GBCartridge cart = {
314 .logo = { _knownHeader[0], _knownHeader[1], _knownHeader[2], _knownHeader[3]}
315 };
316
317 vf->seek(vf, 0x100, SEEK_SET);
318 vf->write(vf, &cart, sizeof(cart));
319}
320
321void GBLoadBIOS(struct GB* gb, struct VFile* vf) {
322 gb->biosVf = vf;
323}
324
325void GBApplyPatch(struct GB* gb, struct Patch* patch) {
326 size_t patchedSize = patch->outputSize(patch, gb->memory.romSize);
327 if (!patchedSize) {
328 return;
329 }
330 if (patchedSize > GB_SIZE_CART_MAX) {
331 patchedSize = GB_SIZE_CART_MAX;
332 }
333 void* newRom = anonymousMemoryMap(GB_SIZE_CART_MAX);
334 if (!patch->applyPatch(patch, gb->memory.rom, gb->pristineRomSize, newRom, patchedSize)) {
335 mappedMemoryFree(newRom, GB_SIZE_CART_MAX);
336 return;
337 }
338 if (gb->romVf) {
339#ifndef FIXED_ROM_BUFFER
340 gb->romVf->unmap(gb->romVf, gb->memory.rom, gb->pristineRomSize);
341#endif
342 gb->romVf->close(gb->romVf);
343 gb->romVf = NULL;
344 }
345 gb->isPristine = false;
346 if (gb->memory.romBase == gb->memory.rom) {
347 gb->memory.romBase = newRom;
348 }
349 gb->memory.rom = newRom;
350 gb->memory.romSize = patchedSize;
351 gb->romCrc32 = doCrc32(gb->memory.rom, gb->memory.romSize);
352 gb->cpu->memory.setActiveRegion(gb->cpu, gb->cpu->pc);
353}
354
355void GBDestroy(struct GB* gb) {
356 GBUnloadROM(gb);
357
358 if (gb->biosVf) {
359 gb->biosVf->close(gb->biosVf);
360 gb->biosVf = 0;
361 }
362
363 GBMemoryDeinit(gb);
364 GBAudioDeinit(&gb->audio);
365 GBVideoDeinit(&gb->video);
366 GBSIODeinit(&gb->sio);
367 mCoreCallbacksListDeinit(&gb->coreCallbacks);
368}
369
370void GBInterruptHandlerInit(struct LR35902InterruptHandler* irqh) {
371 irqh->reset = GBReset;
372 irqh->processEvents = GBProcessEvents;
373 irqh->setInterrupts = GBSetInterrupts;
374 irqh->irqVector = GBIRQVector;
375 irqh->hitIllegal = GBIllegal;
376 irqh->stop = GBStop;
377 irqh->halt = GBHalt;
378}
379
380static uint32_t _GBBiosCRC32(struct VFile* vf) {
381 ssize_t size = vf->size(vf);
382 if (size <= 0 || size > GB_SIZE_CART_BANK0) {
383 return 0;
384 }
385 void* bios = vf->map(vf, size, MAP_READ);
386 uint32_t biosCrc = doCrc32(bios, size);
387 vf->unmap(vf, bios, size);
388 return biosCrc;
389}
390
391bool GBIsBIOS(struct VFile* vf) {
392 switch (_GBBiosCRC32(vf)) {
393 case DMG_BIOS_CHECKSUM:
394 case DMG_2_BIOS_CHECKSUM:
395 case MGB_BIOS_CHECKSUM:
396 case SGB_BIOS_CHECKSUM:
397 case CGB_BIOS_CHECKSUM:
398 return true;
399 default:
400 return false;
401 }
402}
403
404void GBReset(struct LR35902Core* cpu) {
405 struct GB* gb = (struct GB*) cpu->master;
406 gb->memory.romBase = gb->memory.rom;
407 GBDetectModel(gb);
408
409 if (gb->biosVf) {
410 if (!GBIsBIOS(gb->biosVf)) {
411 gb->biosVf->close(gb->biosVf);
412 gb->biosVf = NULL;
413 } else {
414 gb->biosVf->seek(gb->biosVf, 0, SEEK_SET);
415 gb->memory.romBase = malloc(GB_SIZE_CART_BANK0);
416 ssize_t size = gb->biosVf->read(gb->biosVf, gb->memory.romBase, GB_SIZE_CART_BANK0);
417 memcpy(&gb->memory.romBase[size], &gb->memory.rom[size], GB_SIZE_CART_BANK0 - size);
418 if (size > 0x100) {
419 memcpy(&gb->memory.romBase[0x100], &gb->memory.rom[0x100], sizeof(struct GBCartridge));
420 }
421
422 cpu->a = 0;
423 cpu->f.packed = 0;
424 cpu->c = 0;
425 cpu->e = 0;
426 cpu->h = 0;
427 cpu->l = 0;
428 cpu->sp = 0;
429 cpu->pc = 0;
430 }
431 }
432
433 cpu->b = 0;
434 cpu->d = 0;
435
436 gb->timer.internalDiv = 0;
437
438 gb->cpuBlocked = false;
439 gb->earlyExit = false;
440 gb->doubleSpeed = 0;
441
442 if (gb->yankedRomSize) {
443 gb->memory.romSize = gb->yankedRomSize;
444 gb->yankedRomSize = 0;
445 }
446
447 gb->sgbBit = -1;
448 gb->sgbControllers = 0;
449 gb->sgbCurrentController = 0;
450 gb->currentSgbBits = 0;
451 memset(gb->sgbPacket, 0, sizeof(gb->sgbPacket));
452
453 mTimingClear(&gb->timing);
454
455 GBMemoryReset(gb);
456 GBVideoReset(&gb->video);
457 GBTimerReset(&gb->timer);
458 if (!gb->biosVf) {
459 GBSkipBIOS(gb);
460 } else {
461 mTimingSchedule(&gb->timing, &gb->timer.event, 0);
462 }
463
464 GBIOReset(gb);
465 GBAudioReset(&gb->audio);
466 GBSIOReset(&gb->sio);
467
468 cpu->memory.setActiveRegion(cpu, cpu->pc);
469
470 gb->sramMaskWriteback = false;
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 // Fall through
482 case GB_MODEL_DMG:
483 cpu->a = 1;
484 cpu->f.packed = 0xB0;
485 cpu->c = 0x13;
486 cpu->e = 0xD8;
487 cpu->h = 1;
488 cpu->l = 0x4D;
489 gb->timer.internalDiv = 0xABC;
490 nextDiv = 4;
491 break;
492 case GB_MODEL_SGB:
493 cpu->a = 1;
494 cpu->f.packed = 0x00;
495 cpu->c = 0x14;
496 cpu->e = 0x00;
497 cpu->h = 0xC0;
498 cpu->l = 0x60;
499 gb->timer.internalDiv = 0xABC;
500 nextDiv = 4;
501 break;
502 case GB_MODEL_MGB:
503 cpu->a = 0xFF;
504 cpu->f.packed = 0xB0;
505 cpu->c = 0x13;
506 cpu->e = 0xD8;
507 cpu->h = 1;
508 cpu->l = 0x4D;
509 gb->timer.internalDiv = 0xABC;
510 nextDiv = 4;
511 break;
512 case GB_MODEL_SGB2:
513 cpu->a = 0xFF;
514 cpu->f.packed = 0x00;
515 cpu->c = 0x14;
516 cpu->e = 0x00;
517 cpu->h = 0xC0;
518 cpu->l = 0x60;
519 gb->timer.internalDiv = 0xABC;
520 nextDiv = 4;
521 break;
522 case GB_MODEL_AGB:
523 cpu->a = 0x11;
524 cpu->b = 1;
525 cpu->f.packed = 0x00;
526 cpu->c = 0;
527 cpu->e = 0x08;
528 cpu->h = 0;
529 cpu->l = 0x7C;
530 gb->timer.internalDiv = 0x1EA;
531 nextDiv = 0xC;
532 break;
533 case GB_MODEL_CGB:
534 cpu->a = 0x11;
535 cpu->f.packed = 0x80;
536 cpu->c = 0;
537 cpu->e = 0x08;
538 cpu->h = 0;
539 cpu->l = 0x7C;
540 gb->timer.internalDiv = 0x1EA;
541 nextDiv = 0xC;
542 break;
543 }
544
545 cpu->sp = 0xFFFE;
546 cpu->pc = 0x100;
547
548 mTimingDeschedule(&gb->timing, &gb->timer.event);
549 mTimingSchedule(&gb->timing, &gb->timer.event, 0);
550
551 GBIOWrite(gb, REG_LCDC, 0x91);
552
553 if (gb->biosVf) {
554 GBUnmapBIOS(gb);
555 }
556}
557
558void GBUnmapBIOS(struct GB* gb) {
559 if (gb->memory.romBase < gb->memory.rom || gb->memory.romBase > &gb->memory.rom[gb->memory.romSize - 1]) {
560 free(gb->memory.romBase);
561 gb->memory.romBase = gb->memory.rom;
562 }
563 // XXX: Force AGB registers for AGB-mode
564 if (gb->model == GB_MODEL_AGB && gb->cpu->pc == 0x100) {
565 gb->cpu->b = 1;
566 }
567}
568
569void GBDetectModel(struct GB* gb) {
570 if (gb->model != GB_MODEL_AUTODETECT) {
571 return;
572 }
573 if (gb->biosVf) {
574 switch (_GBBiosCRC32(gb->biosVf)) {
575 case DMG_BIOS_CHECKSUM:
576 case DMG_2_BIOS_CHECKSUM:
577 gb->model = GB_MODEL_DMG;
578 break;
579 case MGB_BIOS_CHECKSUM:
580 gb->model = GB_MODEL_MGB;
581 break;
582 case SGB_BIOS_CHECKSUM:
583 gb->model = GB_MODEL_SGB;
584 break;
585 case CGB_BIOS_CHECKSUM:
586 gb->model = GB_MODEL_CGB;
587 break;
588 default:
589 gb->biosVf->close(gb->biosVf);
590 gb->biosVf = NULL;
591 }
592 }
593 if (gb->model == GB_MODEL_AUTODETECT && gb->memory.rom) {
594 const struct GBCartridge* cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
595 if (cart->cgb & 0x80) {
596 gb->model = GB_MODEL_CGB;
597 } else if (cart->sgb == 0x03 && cart->oldLicensee == 0x33) {
598 gb->model = GB_MODEL_SGB;
599 } else {
600 gb->model = GB_MODEL_DMG;
601 }
602 }
603
604 switch (gb->model) {
605 case GB_MODEL_DMG:
606 case GB_MODEL_SGB:
607 case GB_MODEL_AUTODETECT: //Silence warnings
608 gb->audio.style = GB_AUDIO_DMG;
609 break;
610 case GB_MODEL_MGB:
611 case GB_MODEL_SGB2:
612 gb->audio.style = GB_AUDIO_MGB;
613 break;
614 case GB_MODEL_AGB:
615 case GB_MODEL_CGB:
616 gb->audio.style = GB_AUDIO_CGB;
617 break;
618 }
619}
620
621void GBUpdateIRQs(struct GB* gb) {
622 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
623 if (!irqs) {
624 gb->cpu->irqPending = false;
625 return;
626 }
627 gb->cpu->halted = false;
628
629 if (!gb->memory.ime) {
630 gb->cpu->irqPending = false;
631 return;
632 }
633 if (gb->cpu->irqPending) {
634 return;
635 }
636 LR35902RaiseIRQ(gb->cpu);
637}
638
639void GBProcessEvents(struct LR35902Core* cpu) {
640 struct GB* gb = (struct GB*) cpu->master;
641 do {
642 int32_t cycles = cpu->cycles;
643 int32_t nextEvent;
644
645 cpu->cycles = 0;
646 cpu->nextEvent = INT_MAX;
647
648 nextEvent = cycles;
649 do {
650 nextEvent = mTimingTick(&gb->timing, nextEvent);
651 } while (gb->cpuBlocked);
652 cpu->nextEvent = nextEvent;
653
654 if (cpu->halted) {
655 cpu->cycles = cpu->nextEvent;
656 if (!gb->memory.ie || !gb->memory.ime) {
657 break;
658 }
659 }
660 if (gb->earlyExit) {
661 break;
662 }
663 } while (cpu->cycles >= cpu->nextEvent);
664 gb->earlyExit = false;
665}
666
667void GBSetInterrupts(struct LR35902Core* cpu, bool enable) {
668 struct GB* gb = (struct GB*) cpu->master;
669 mTimingDeschedule(&gb->timing, &gb->eiPending);
670 if (!enable) {
671 gb->memory.ime = false;
672 GBUpdateIRQs(gb);
673 } else {
674 mTimingSchedule(&gb->timing, &gb->eiPending, 4);
675 }
676}
677
678uint16_t GBIRQVector(struct LR35902Core* cpu) {
679 struct GB* gb = (struct GB*) cpu->master;
680 int irqs = gb->memory.ie & gb->memory.io[REG_IF];
681
682 if (irqs & (1 << GB_IRQ_VBLANK)) {
683 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_VBLANK);
684 return GB_VECTOR_VBLANK;
685 }
686 if (irqs & (1 << GB_IRQ_LCDSTAT)) {
687 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_LCDSTAT);
688 return GB_VECTOR_LCDSTAT;
689 }
690 if (irqs & (1 << GB_IRQ_TIMER)) {
691 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_TIMER);
692 return GB_VECTOR_TIMER;
693 }
694 if (irqs & (1 << GB_IRQ_SIO)) {
695 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_SIO);
696 return GB_VECTOR_SIO;
697 }
698 if (irqs & (1 << GB_IRQ_KEYPAD)) {
699 gb->memory.io[REG_IF] &= ~(1 << GB_IRQ_KEYPAD);
700 return GB_VECTOR_KEYPAD;
701 }
702 return 0;
703}
704
705static void _enableInterrupts(struct mTiming* timing, void* user, uint32_t cyclesLate) {
706 UNUSED(timing);
707 UNUSED(cyclesLate);
708 struct GB* gb = user;
709 gb->memory.ime = true;
710 GBUpdateIRQs(gb);
711}
712
713void GBHalt(struct LR35902Core* cpu) {
714 struct GB* gb = (struct GB*) cpu->master;
715 if (!(gb->memory.ie & gb->memory.io[REG_IF])) {
716 cpu->cycles = cpu->nextEvent;
717 cpu->halted = true;
718 } else if (gb->model < GB_MODEL_CGB) {
719 mLOG(GB, STUB, "Unimplemented HALT bug");
720 }
721}
722
723void GBStop(struct LR35902Core* cpu) {
724 struct GB* gb = (struct GB*) cpu->master;
725 if (cpu->bus) {
726 mLOG(GB, GAME_ERROR, "Hit illegal stop at address %04X:%02X", cpu->pc, cpu->bus);
727 }
728 if (gb->memory.io[REG_KEY1] & 1) {
729 gb->doubleSpeed ^= 1;
730 gb->audio.timingFactor = gb->doubleSpeed + 1;
731 gb->memory.io[REG_KEY1] = 0;
732 gb->memory.io[REG_KEY1] |= gb->doubleSpeed << 7;
733 } else if (cpu->bus) {
734#ifdef USE_DEBUGGERS
735 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
736 struct mDebuggerEntryInfo info = {
737 .address = cpu->pc - 1,
738 .type.bp.opcode = 0x1000 | cpu->bus
739 };
740 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
741 }
742#endif
743 // Hang forever
744 gb->memory.ime = 0;
745 cpu->pc -= 2;
746 }
747 // TODO: Actually stop
748}
749
750void GBIllegal(struct LR35902Core* cpu) {
751 struct GB* gb = (struct GB*) cpu->master;
752 mLOG(GB, GAME_ERROR, "Hit illegal opcode at address %04X:%02X", cpu->pc, cpu->bus);
753#ifdef USE_DEBUGGERS
754 if (cpu->components && cpu->components[CPU_COMPONENT_DEBUGGER]) {
755 struct mDebuggerEntryInfo info = {
756 .address = cpu->pc,
757 .type.bp.opcode = cpu->bus
758 };
759 mDebuggerEnter((struct mDebugger*) cpu->components[CPU_COMPONENT_DEBUGGER], DEBUGGER_ENTER_ILLEGAL_OP, &info);
760 }
761#endif
762 // Hang forever
763 gb->memory.ime = 0;
764 --cpu->pc;
765}
766
767bool GBIsROM(struct VFile* vf) {
768 if (!vf) {
769 return false;
770 }
771 vf->seek(vf, 0x104, SEEK_SET);
772 uint8_t header[4];
773
774 if (vf->read(vf, &header, sizeof(header)) < (ssize_t) sizeof(header)) {
775 return false;
776 }
777 if (memcmp(header, _knownHeader, sizeof(header))) {
778 return false;
779 }
780 return true;
781}
782
783void GBGetGameTitle(const struct GB* gb, char* out) {
784 const struct GBCartridge* cart = NULL;
785 if (gb->memory.rom) {
786 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
787 }
788 if (!cart) {
789 return;
790 }
791 if (cart->oldLicensee != 0x33) {
792 memcpy(out, cart->titleLong, 16);
793 } else {
794 memcpy(out, cart->titleShort, 11);
795 }
796}
797
798void GBGetGameCode(const struct GB* gb, char* out) {
799 memset(out, 0, 8);
800 const struct GBCartridge* cart = NULL;
801 if (gb->memory.rom) {
802 cart = (const struct GBCartridge*) &gb->memory.rom[0x100];
803 }
804 if (!cart) {
805 return;
806 }
807 if (cart->cgb == 0xC0) {
808 memcpy(out, "CGB-????", 8);
809 } else {
810 memcpy(out, "DMG-????", 8);
811 }
812 if (cart->oldLicensee == 0x33) {
813 memcpy(&out[4], cart->maker, 4);
814 }
815}
816
817void GBFrameEnded(struct GB* gb) {
818 GBSramClean(gb, gb->video.frameCounter);
819
820 if (gb->cpu->components && gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE]) {
821 struct mCheatDevice* device = (struct mCheatDevice*) gb->cpu->components[CPU_COMPONENT_CHEAT_DEVICE];
822 size_t i;
823 for (i = 0; i < mCheatSetsSize(&device->cheats); ++i) {
824 struct mCheatSet* cheats = *mCheatSetsGetPointer(&device->cheats, i);
825 mCheatRefresh(device, cheats);
826 }
827 }
828
829 GBTestKeypadIRQ(gb);
830}
831
832enum GBModel GBNameToModel(const char* model) {
833 if (strcasecmp(model, "DMG") == 0) {
834 return GB_MODEL_DMG;
835 } else if (strcasecmp(model, "CGB") == 0) {
836 return GB_MODEL_CGB;
837 } else if (strcasecmp(model, "AGB") == 0) {
838 return GB_MODEL_AGB;
839 } else if (strcasecmp(model, "SGB") == 0) {
840 return GB_MODEL_SGB;
841 } else if (strcasecmp(model, "MGB") == 0) {
842 return GB_MODEL_MGB;
843 } else if (strcasecmp(model, "SGB2") == 0) {
844 return GB_MODEL_SGB2;
845 }
846 return GB_MODEL_AUTODETECT;
847}
848
849const char* GBModelToName(enum GBModel model) {
850 switch (model) {
851 case GB_MODEL_DMG:
852 return "DMG";
853 case GB_MODEL_SGB:
854 return "SGB";
855 case GB_MODEL_MGB:
856 return "MGB";
857 case GB_MODEL_SGB2:
858 return "SGB2";
859 case GB_MODEL_CGB:
860 return "CGB";
861 case GB_MODEL_AGB:
862 return "AGB";
863 default:
864 case GB_MODEL_AUTODETECT:
865 return NULL;
866 }
867}