all repos — mgba @ 620adbd5777f75fbb5d7b01b1ac534d72293f240

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