all repos — mgba @ 2db6d27496dcd66af0ab45a51a6bf94a4862b59d

mGBA Game Boy Advance Emulator

src/gba/gba.c (view raw)

  1#include "gba.h"
  2
  3#include "gba-bios.h"
  4#include "gba-io.h"
  5#include "gba-thread.h"
  6#include "memory.h"
  7
  8#include "debugger.h"
  9
 10#include <limits.h>
 11#include <stdarg.h>
 12#include <stdio.h>
 13#include <stdlib.h>
 14#include <string.h>
 15#include <sys/stat.h>
 16
 17const uint32_t GBA_ARM7TDMI_FREQUENCY = 0x1000000;
 18
 19enum {
 20	SP_BASE_SYSTEM = 0x03FFFF00,
 21	SP_BASE_IRQ = 0x03FFFFA0,
 22	SP_BASE_SUPERVISOR = 0x03FFFFE0
 23};
 24
 25struct GBACartridgeOverride {
 26	uint32_t id;
 27	enum SavedataType type;
 28	int gpio;
 29};
 30
 31static const struct GBACartridgeOverride _overrides[] = {
 32	// Boktai: The Sun is in Your Hand
 33	{ 'EI3U', SAVEDATA_EEPROM, GPIO_RTC | GPIO_LIGHT_SENSOR },
 34	{ 'PI3U', SAVEDATA_EEPROM, GPIO_RTC | GPIO_LIGHT_SENSOR },
 35
 36	// Boktai 2: Solar Boy Django
 37	{ 'E23U', SAVEDATA_EEPROM, GPIO_RTC | GPIO_LIGHT_SENSOR },
 38	{ 'P23U', SAVEDATA_EEPROM, GPIO_RTC | GPIO_LIGHT_SENSOR },
 39
 40	// Drill Dozer
 41	{ 'J94V', SAVEDATA_SRAM, GPIO_RUMBLE },
 42	{ 'E94V', SAVEDATA_SRAM, GPIO_RUMBLE },
 43
 44	// Pokemon Ruby
 45	{ 'JVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 46	{ 'EVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 47	{ 'PVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 48	{ 'IVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 49	{ 'SVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 50	{ 'DVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 51	{ 'FVXA', SAVEDATA_FLASH1M, GPIO_RTC },
 52
 53	// Pokemon Sapphire
 54	{ 'JPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 55	{ 'EPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 56	{ 'PPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 57	{ 'IPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 58	{ 'SPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 59	{ 'DPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 60	{ 'FPXA', SAVEDATA_FLASH1M, GPIO_RTC },
 61
 62	// Pokemon Emerald
 63	{ 'JEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 64	{ 'EEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 65	{ 'PEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 66	{ 'IEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 67	{ 'SEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 68	{ 'DEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 69	{ 'FEPB', SAVEDATA_FLASH1M, GPIO_RTC },
 70
 71	// Pokemon FireRed
 72	{ 'JRPB', SAVEDATA_FLASH1M, GPIO_NONE },
 73	{ 'ERPB', SAVEDATA_FLASH1M, GPIO_NONE },
 74	{ 'PRPB', SAVEDATA_FLASH1M, GPIO_NONE },
 75
 76	// Pokemon LeafGreen
 77	{ 'JGPB', SAVEDATA_FLASH1M, GPIO_NONE },
 78	{ 'EGPB', SAVEDATA_FLASH1M, GPIO_NONE },
 79	{ 'PGPB', SAVEDATA_FLASH1M, GPIO_NONE },
 80
 81	// RockMan EXE 4.5 - Real Operation
 82	{ 'J4RB', SAVEDATA_FLASH512, GPIO_RTC },
 83
 84	// Super Mario Advance 4
 85	{ 'J4XA', SAVEDATA_FLASH1M, GPIO_NONE },
 86	{ 'E4XA', SAVEDATA_FLASH1M, GPIO_NONE },
 87	{ 'P4XA', SAVEDATA_FLASH1M, GPIO_NONE },
 88
 89	// Wario Ware Twisted
 90	{ 'JWZR', SAVEDATA_SRAM, GPIO_RUMBLE | GPIO_GYRO },
 91	{ 'EWZR', SAVEDATA_SRAM, GPIO_RUMBLE | GPIO_GYRO },
 92	{ 'PWZR', SAVEDATA_SRAM, GPIO_RUMBLE | GPIO_GYRO },
 93
 94	{ 0, 0, 0 }
 95};
 96
 97static void GBAProcessEvents(struct ARMBoard* board);
 98static int32_t GBATimersProcessEvents(struct GBA* gba, int32_t cycles);
 99static void GBAHitStub(struct ARMBoard* board, uint32_t opcode);
100static void GBAIllegal(struct ARMBoard* board, uint32_t opcode);
101
102static void _checkOverrides(struct GBA* gba, uint32_t code);
103
104void GBAInit(struct GBA* gba) {
105	gba->debugger = 0;
106	gba->savefile = 0;
107
108	ARMInit(&gba->cpu);
109
110	gba->memory.p = gba;
111	GBAMemoryInit(&gba->memory);
112	ARMAssociateMemory(&gba->cpu, &gba->memory.d);
113
114	gba->board.p = gba;
115	GBABoardInit(&gba->board);
116	ARMAssociateBoard(&gba->cpu, &gba->board.d);
117
118	gba->video.p = gba;
119	GBAVideoInit(&gba->video);
120
121	gba->audio.p = gba;
122	GBAAudioInit(&gba->audio);
123
124	GBAIOInit(gba);
125
126	gba->timersEnabled = 0;
127	memset(gba->timers, 0, sizeof(gba->timers));
128
129	gba->springIRQ = 0;
130	gba->keySource = 0;
131	gba->rotationSource = 0;
132	gba->rumble = 0;
133
134	gba->logLevel = GBA_LOG_INFO | GBA_LOG_WARN | GBA_LOG_ERROR;
135
136	ARMReset(&gba->cpu);
137}
138
139void GBADeinit(struct GBA* gba) {
140	GBAMemoryDeinit(&gba->memory);
141	GBAVideoDeinit(&gba->video);
142	GBAAudioDeinit(&gba->audio);
143}
144
145void GBABoardInit(struct GBABoard* board) {
146	board->d.reset = GBABoardReset;
147	board->d.processEvents = GBAProcessEvents;
148	board->d.swi16 = GBASwi16;
149	board->d.swi32 = GBASwi32;
150	board->d.hitIllegal = GBAIllegal;
151	board->d.readCPSR = GBATestIRQ;
152	board->d.hitStub = GBAHitStub;
153}
154
155void GBABoardReset(struct ARMBoard* board) {
156	struct ARMCore* cpu = board->cpu;
157	ARMSetPrivilegeMode(cpu, MODE_IRQ);
158	cpu->gprs[ARM_SP] = SP_BASE_IRQ;
159	ARMSetPrivilegeMode(cpu, MODE_SUPERVISOR);
160	cpu->gprs[ARM_SP] = SP_BASE_SUPERVISOR;
161	ARMSetPrivilegeMode(cpu, MODE_SYSTEM);
162	cpu->gprs[ARM_SP] = SP_BASE_SYSTEM;
163}
164
165static void GBAProcessEvents(struct ARMBoard* board) {
166	struct GBABoard* gbaBoard = (struct GBABoard*) board;
167	int32_t cycles = board->cpu->cycles;
168	int32_t nextEvent = INT_MAX;
169	int32_t testEvent;
170
171	if (gbaBoard->p->springIRQ) {
172		ARMRaiseIRQ(&gbaBoard->p->cpu);
173		gbaBoard->p->springIRQ = 0;
174	}
175
176	testEvent = GBAVideoProcessEvents(&gbaBoard->p->video, cycles);
177	if (testEvent < nextEvent) {
178		nextEvent = testEvent;
179	}
180
181	testEvent = GBAAudioProcessEvents(&gbaBoard->p->audio, cycles);
182	if (testEvent < nextEvent) {
183		nextEvent = testEvent;
184	}
185
186	testEvent = GBAMemoryProcessEvents(&gbaBoard->p->memory, cycles);
187	if (testEvent < nextEvent) {
188		nextEvent = testEvent;
189	}
190
191	testEvent = GBATimersProcessEvents(gbaBoard->p, cycles);
192	if (testEvent < nextEvent) {
193		nextEvent = testEvent;
194	}
195
196	board->cpu->cycles = 0;
197	board->cpu->nextEvent = nextEvent;
198}
199
200static int32_t GBATimersProcessEvents(struct GBA* gba, int32_t cycles) {
201	int32_t nextEvent = INT_MAX;
202	if (gba->timersEnabled) {
203		struct GBATimer* timer;
204		struct GBATimer* nextTimer;
205
206		timer = &gba->timers[0];
207		if (timer->enable) {
208			timer->nextEvent -= cycles;
209			timer->lastEvent -= cycles;
210			if (timer->nextEvent <= 0) {
211				timer->lastEvent = timer->nextEvent;
212				timer->nextEvent += timer->overflowInterval;
213				gba->memory.io[REG_TM0CNT_LO >> 1] = timer->reload;
214				timer->oldReload = timer->reload;
215
216				if (timer->doIrq) {
217					GBARaiseIRQ(gba, IRQ_TIMER0);
218				}
219
220				if (gba->audio.enable) {
221					if ((gba->audio.chALeft || gba->audio.chARight) && gba->audio.chATimer == 0) {
222						GBAAudioSampleFIFO(&gba->audio, 0);
223					}
224
225					if ((gba->audio.chBLeft || gba->audio.chBRight) && gba->audio.chBTimer == 0) {
226						GBAAudioSampleFIFO(&gba->audio, 1);
227					}
228				}
229
230				nextTimer = &gba->timers[1];
231				if (nextTimer->countUp) {
232					++gba->memory.io[REG_TM1CNT_LO >> 1];
233					if (!gba->memory.io[REG_TM1CNT_LO >> 1]) {
234						nextTimer->nextEvent = 0;
235					}
236				}
237			}
238			nextEvent = timer->nextEvent;
239		}
240
241		timer = &gba->timers[1];
242		if (timer->enable) {
243			timer->nextEvent -= cycles;
244			timer->lastEvent -= cycles;
245			if (timer->nextEvent <= 0) {
246				timer->lastEvent = timer->nextEvent;
247				timer->nextEvent += timer->overflowInterval;
248				gba->memory.io[REG_TM1CNT_LO >> 1] = timer->reload;
249				timer->oldReload = timer->reload;
250
251				if (timer->doIrq) {
252					GBARaiseIRQ(gba, IRQ_TIMER1);
253				}
254
255				if (gba->audio.enable) {
256					if ((gba->audio.chALeft || gba->audio.chARight) && gba->audio.chATimer == 1) {
257						GBAAudioSampleFIFO(&gba->audio, 0);
258					}
259
260					if ((gba->audio.chBLeft || gba->audio.chBRight) && gba->audio.chBTimer == 1) {
261						GBAAudioSampleFIFO(&gba->audio, 1);
262					}
263				}
264
265				if (timer->countUp) {
266					timer->nextEvent = INT_MAX;
267				}
268
269				nextTimer = &gba->timers[2];
270				if (nextTimer->countUp) {
271					++gba->memory.io[REG_TM2CNT_LO >> 1];
272					if (!gba->memory.io[REG_TM2CNT_LO >> 1]) {
273						nextTimer->nextEvent = 0;
274					}
275				}
276			}
277			if (timer->nextEvent < nextEvent) {
278				nextEvent = timer->nextEvent;
279			}
280		}
281
282		timer = &gba->timers[2];
283		if (timer->enable) {
284			timer->nextEvent -= cycles;
285			timer->lastEvent -= cycles;
286			nextEvent = timer->nextEvent;
287			if (timer->nextEvent <= 0) {
288				timer->lastEvent = timer->nextEvent;
289				timer->nextEvent += timer->overflowInterval;
290				gba->memory.io[REG_TM2CNT_LO >> 1] = timer->reload;
291				timer->oldReload = timer->reload;
292
293				if (timer->doIrq) {
294					GBARaiseIRQ(gba, IRQ_TIMER2);
295				}
296
297				if (timer->countUp) {
298					timer->nextEvent = INT_MAX;
299				}
300
301				nextTimer = &gba->timers[3];
302				if (nextTimer->countUp) {
303					++gba->memory.io[REG_TM3CNT_LO >> 1];
304					if (!gba->memory.io[REG_TM3CNT_LO >> 1]) {
305						nextTimer->nextEvent = 0;
306					}
307				}
308			}
309			if (timer->nextEvent < nextEvent) {
310				nextEvent = timer->nextEvent;
311			}
312		}
313
314		timer = &gba->timers[3];
315		if (timer->enable) {
316			timer->nextEvent -= cycles;
317			timer->lastEvent -= cycles;
318			nextEvent = timer->nextEvent;
319			if (timer->nextEvent <= 0) {
320				timer->lastEvent = timer->nextEvent;
321				timer->nextEvent += timer->overflowInterval;
322				gba->memory.io[REG_TM3CNT_LO >> 1] = timer->reload;
323				timer->oldReload = timer->reload;
324
325				if (timer->doIrq) {
326					GBARaiseIRQ(gba, IRQ_TIMER3);
327				}
328
329				if (timer->countUp) {
330					timer->nextEvent = INT_MAX;
331				}
332			}
333			if (timer->nextEvent < nextEvent) {
334				nextEvent = timer->nextEvent;
335			}
336		}
337	}
338	return nextEvent;
339}
340
341#ifdef USE_DEBUGGER
342void GBAAttachDebugger(struct GBA* gba, struct ARMDebugger* debugger) {
343	ARMDebuggerInit(debugger, &gba->cpu);
344	gba->debugger = debugger;
345}
346#endif
347
348void GBALoadROM(struct GBA* gba, int fd, const char* fname) {
349	struct stat info;
350	gba->memory.rom = fileMemoryMap(fd, SIZE_CART0, MEMORY_READ);
351	gba->activeFile = fname;
352	fstat(fd, &info);
353	gba->memory.romSize = info.st_size;
354	if (gba->savefile) {
355		GBASavedataInit(&gba->memory.savedata, gba->savefile);
356	}
357	GBAGPIOInit(&gba->memory.gpio, &((uint16_t*) gba->memory.rom)[GPIO_REG_DATA >> 1]);
358	_checkOverrides(gba, ((struct GBACartridge*) gba->memory.rom)->id);
359	// TODO: error check
360}
361
362void GBALoadBIOS(struct GBA* gba, int fd) {
363	gba->memory.bios = fileMemoryMap(fd, SIZE_BIOS, MEMORY_READ);
364	gba->memory.fullBios = 1;
365	uint32_t checksum = GBAChecksum(gba->memory.bios, SIZE_BIOS);
366	GBALog(gba, GBA_LOG_DEBUG, "BIOS Checksum: 0x%X", checksum);
367	if (checksum == GBA_BIOS_CHECKSUM) {
368		GBALog(gba, GBA_LOG_INFO, "Official GBA BIOS detected");
369	} else if (checksum == GBA_DS_BIOS_CHECKSUM) {
370		GBALog(gba, GBA_LOG_INFO, "Official GBA (DS) BIOS detected");
371	} else {
372		GBALog(gba, GBA_LOG_WARN, "BIOS checksum incorrect");
373	}
374	if ((gba->cpu.gprs[ARM_PC] >> BASE_OFFSET) == BASE_BIOS) {
375		gba->memory.d.setActiveRegion(&gba->memory.d, gba->cpu.gprs[ARM_PC]);
376	}
377	// TODO: error check
378}
379
380void GBATimerUpdateRegister(struct GBA* gba, int timer) {
381	struct GBATimer* currentTimer = &gba->timers[timer];
382	if (currentTimer->enable && !currentTimer->countUp) {
383		gba->memory.io[(REG_TM0CNT_LO + (timer << 2)) >> 1] = currentTimer->oldReload + ((gba->cpu.cycles - currentTimer->lastEvent) >> currentTimer->prescaleBits);
384	}
385}
386
387void GBATimerWriteTMCNT_LO(struct GBA* gba, int timer, uint16_t reload) {
388	gba->timers[timer].reload = reload;
389}
390
391void GBATimerWriteTMCNT_HI(struct GBA* gba, int timer, uint16_t control) {
392	struct GBATimer* currentTimer = &gba->timers[timer];
393	GBATimerUpdateRegister(gba, timer);
394
395	int oldPrescale = currentTimer->prescaleBits;
396	switch (control & 0x0003) {
397	case 0x0000:
398		currentTimer->prescaleBits = 0;
399		break;
400	case 0x0001:
401		currentTimer->prescaleBits = 6;
402		break;
403	case 0x0002:
404		currentTimer->prescaleBits = 8;
405		break;
406	case 0x0003:
407		currentTimer->prescaleBits = 10;
408		break;
409	}
410	currentTimer->countUp = !!(control & 0x0004);
411	currentTimer->doIrq = !!(control & 0x0040);
412	currentTimer->overflowInterval = (0x10000 - currentTimer->reload) << currentTimer->prescaleBits;
413	int wasEnabled = currentTimer->enable;
414	currentTimer->enable = !!(control & 0x0080);
415	if (!wasEnabled && currentTimer->enable) {
416		if (!currentTimer->countUp) {
417			currentTimer->nextEvent = gba->cpu.cycles + currentTimer->overflowInterval;
418		} else {
419			currentTimer->nextEvent = INT_MAX;
420		}
421		gba->memory.io[(REG_TM0CNT_LO + (timer << 2)) >> 1] = currentTimer->reload;
422		currentTimer->oldReload = currentTimer->reload;
423		gba->timersEnabled |= 1 << timer;
424	} else if (wasEnabled && !currentTimer->enable) {
425		if (!currentTimer->countUp) {
426			gba->memory.io[(REG_TM0CNT_LO + (timer << 2)) >> 1] = currentTimer->oldReload + ((gba->cpu.cycles - currentTimer->lastEvent) >> oldPrescale);
427		}
428		gba->timersEnabled &= ~(1 << timer);
429	} else if (currentTimer->prescaleBits != oldPrescale && !currentTimer->countUp) {
430		// FIXME: this might be before present
431		currentTimer->nextEvent = currentTimer->lastEvent + currentTimer->overflowInterval;
432	}
433
434	if (currentTimer->nextEvent < gba->cpu.nextEvent) {
435		gba->cpu.nextEvent = currentTimer->nextEvent;
436	}
437};
438
439void GBAWriteIE(struct GBA* gba, uint16_t value) {
440	if (value & (1 << IRQ_SIO)) {
441		GBALog(gba, GBA_LOG_STUB, "SIO interrupts not implemented");
442	}
443
444	if (value & (1 << IRQ_KEYPAD)) {
445		GBALog(gba, GBA_LOG_STUB, "Keypad interrupts not implemented");
446	}
447
448	if (value & (1 << IRQ_GAMEPAK)) {
449		GBALog(gba, GBA_LOG_STUB, "Gamepak interrupts not implemented");
450	}
451
452	if (gba->memory.io[REG_IME >> 1] && value & gba->memory.io[REG_IF >> 1]) {
453		ARMRaiseIRQ(&gba->cpu);
454	}
455}
456
457void GBAWriteIME(struct GBA* gba, uint16_t value) {
458	if (value && gba->memory.io[REG_IE >> 1] & gba->memory.io[REG_IF >> 1]) {
459		ARMRaiseIRQ(&gba->cpu);
460	}
461}
462
463void GBARaiseIRQ(struct GBA* gba, enum GBAIRQ irq) {
464	gba->memory.io[REG_IF >> 1] |= 1 << irq;
465
466	if (gba->memory.io[REG_IME >> 1] && (gba->memory.io[REG_IE >> 1] & 1 << irq)) {
467		ARMRaiseIRQ(&gba->cpu);
468	}
469}
470
471void GBATestIRQ(struct ARMBoard* board) {
472	struct GBABoard* gbaBoard = (struct GBABoard*) board;
473	struct GBA* gba = gbaBoard->p;
474	if (gba->memory.io[REG_IME >> 1] && gba->memory.io[REG_IE >> 1] & gba->memory.io[REG_IF >> 1]) {
475		gba->springIRQ = 1;
476		gba->cpu.nextEvent = 0;
477	}
478}
479
480int GBAWaitForIRQ(struct GBA* gba) {
481	int irqs = gba->memory.io[REG_IF >> 1];
482	int newIRQs = 0;
483	gba->memory.io[REG_IF >> 1] = 0;
484	while (1) {
485		if (gba->cpu.nextEvent == INT_MAX) {
486			break;
487		} else {
488			gba->cpu.cycles = gba->cpu.nextEvent;
489			GBAProcessEvents(&gba->board.d);
490			if (gba->memory.io[REG_IF >> 1]) {
491				newIRQs = gba->memory.io[REG_IF >> 1];
492				break;
493			}
494		}
495	}
496	gba->memory.io[REG_IF >> 1] = newIRQs | irqs;
497	return newIRQs;
498}
499
500int GBAHalt(struct GBA* gba) {
501	return GBAWaitForIRQ(gba);
502}
503
504void GBALog(struct GBA* gba, enum GBALogLevel level, const char* format, ...) {
505	if (!gba) {
506		struct GBAThread* threadContext = GBAThreadGetContext();
507		if (threadContext) {
508			gba = threadContext->gba;
509		}
510	}
511	if (gba && !(level & gba->logLevel)) {
512		return;
513	}
514	va_list args;
515	va_start(args, format);
516	vprintf(format, args);
517	va_end(args);
518	printf("\n");
519}
520
521void GBAHitStub(struct ARMBoard* board, uint32_t opcode) {
522	struct GBABoard* gbaBoard = (struct GBABoard*) board;
523	GBALog(gbaBoard->p, GBA_LOG_STUB, "Stub opcode: %08x", opcode);
524#ifdef USE_DEBUGGER
525	if (!gbaBoard->p->debugger) {
526		abort();
527	} else {
528		ARMDebuggerEnter(gbaBoard->p->debugger);
529	}
530#else
531	abort();
532#endif
533}
534
535void GBAIllegal(struct ARMBoard* board, uint32_t opcode) {
536	struct GBABoard* gbaBoard = (struct GBABoard*) board;
537	GBALog(gbaBoard->p, GBA_LOG_WARN, "Illegal opcode: %08x", opcode);
538#ifdef USE_DEBUGGER
539	if (gbaBoard->p->debugger) {
540		ARMDebuggerEnter(gbaBoard->p->debugger);
541	}
542#endif
543}
544
545void _checkOverrides(struct GBA* gba, uint32_t id) {
546	int i;
547	for (i = 0; _overrides[i].id; ++i) {
548		if (_overrides[i].id == id) {
549			switch (_overrides[i].type) {
550				case SAVEDATA_FLASH512:
551				case SAVEDATA_FLASH1M:
552					gba->memory.savedata.type = _overrides[i].type;
553					GBASavedataInitFlash(&gba->memory.savedata);
554					break;
555				case SAVEDATA_EEPROM:
556					GBASavedataInitEEPROM(&gba->memory.savedata);
557					break;
558				case SAVEDATA_SRAM:
559					GBASavedataInitSRAM(&gba->memory.savedata);
560					break;
561				case SAVEDATA_NONE:
562					break;
563			}
564
565			if (_overrides[i].gpio & GPIO_RTC) {
566				GBAGPIOInitRTC(&gba->memory.gpio);
567			}
568
569			if (_overrides[i].gpio & GPIO_GYRO) {
570				GBAGPIOInitGyro(&gba->memory.gpio);
571			}
572
573			if (_overrides[i].gpio & GPIO_RUMBLE) {
574				GBAGPIOInitRumble(&gba->memory.gpio);
575			}
576			return;
577		}
578	}
579}