all repos — mgba @ 388dbc08513eaabfa99bce533f10df32e8627e23

mGBA Game Boy Advance Emulator

src/gba/gba-memory.c (view raw)

  1#include "gba-memory.h"
  2
  3#include "gba-io.h"
  4#include "hle-bios.h"
  5
  6#include <limits.h>
  7#include <string.h>
  8#include <sys/mman.h>
  9
 10static const char* GBA_CANNOT_MMAP = "Could not map memory";
 11
 12static void GBASetActiveRegion(struct ARMMemory* memory, uint32_t region);
 13static int GBAWaitMultiple(struct ARMMemory* memory, uint32_t startAddress, int count);
 14
 15static const char GBA_BASE_WAITSTATES[16] = { 0, 0, 2, 0, 0, 0, 0, 0, 4, 4, 4, 4, 4, 4, 4 };
 16static const char GBA_BASE_WAITSTATES_32[16] = { 0, 0, 4, 0, 0, 0, 0, 0, 7, 7, 9, 9, 13, 13, 9 };
 17static const char GBA_BASE_WAITSTATES_SEQ[16] = { 0, 0, 2, 0, 0, 0, 0, 0, 2, 2, 4, 4, 8, 8, 4 };
 18static const char GBA_BASE_WAITSTATES_SEQ_32[16] = { 0, 0, 4, 0, 0, 0, 0, 0, 5, 5, 9, 9, 17, 17, 9 };
 19static const char GBA_ROM_WAITSTATES[] = { 4, 3, 2, 8 };
 20static const char GBA_ROM_WAITSTATES_SEQ[] = { 2, 1, 4, 1, 8, 1 };
 21static const int DMA_OFFSET[] = { 1, -1, 0, 1 };
 22
 23void GBAMemoryInit(struct GBAMemory* memory) {
 24	memory->d.load32 = GBALoad32;
 25	memory->d.load16 = GBALoad16;
 26	memory->d.loadU16 = GBALoadU16;
 27	memory->d.load8 = GBALoad8;
 28	memory->d.loadU8 = GBALoadU8;
 29	memory->d.store32 = GBAStore32;
 30	memory->d.store16 = GBAStore16;
 31	memory->d.store8 = GBAStore8;
 32
 33	memory->bios = (uint32_t*) hleBios;
 34	memory->wram = mmap(0, SIZE_WORKING_RAM, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
 35	memory->iwram = mmap(0, SIZE_WORKING_IRAM, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
 36	memory->rom = 0;
 37	memset(memory->io, 0, sizeof(memory->io));
 38	memset(memory->dma, 0, sizeof(memory->dma));
 39
 40	if (!memory->wram || !memory->iwram) {
 41		GBAMemoryDeinit(memory);
 42		memory->p->errno = GBA_OUT_OF_MEMORY;
 43		memory->p->errstr = GBA_CANNOT_MMAP;
 44	}
 45
 46	GBASavedataInit(&memory->savedata, "test.sav");
 47
 48	int i;
 49	for (i = 0; i < 16; ++i) {
 50		memory->waitstates16[i] = GBA_BASE_WAITSTATES[i];
 51		memory->waitstatesSeq16[i] = GBA_BASE_WAITSTATES_SEQ[i];
 52		memory->waitstatesPrefetch16[i] = GBA_BASE_WAITSTATES_SEQ[i];
 53		memory->waitstates32[i] = GBA_BASE_WAITSTATES_32[i];
 54		memory->waitstatesSeq32[i] = GBA_BASE_WAITSTATES_SEQ_32[i];
 55		memory->waitstatesPrefetch32[i] = GBA_BASE_WAITSTATES_SEQ_32[i];
 56	}
 57	for (; i < 256; ++i) {
 58		memory->waitstates16[i] = 0;
 59		memory->waitstatesSeq16[i] = 0;
 60		memory->waitstatesPrefetch16[i] = 0;
 61		memory->waitstates32[i] = 0;
 62		memory->waitstatesSeq32[i] = 0;
 63		memory->waitstatesPrefetch32[i] = 0;
 64	}
 65
 66	memory->activeRegion = 0;
 67	memory->d.activeRegion = 0;
 68	memory->d.activeMask = 0;
 69	memory->d.setActiveRegion = GBASetActiveRegion;
 70	memory->d.activePrefetchCycles32 = 0;
 71	memory->d.activePrefetchCycles16 = 0;
 72	memory->d.waitMultiple = GBAWaitMultiple;
 73}
 74
 75void GBAMemoryDeinit(struct GBAMemory* memory) {
 76	munmap(memory->wram, SIZE_WORKING_RAM);
 77	munmap(memory->iwram, SIZE_WORKING_IRAM);
 78	GBASavedataDeinit(&memory->savedata);
 79}
 80
 81static void GBASetActiveRegion(struct ARMMemory* memory, uint32_t address) {
 82	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
 83
 84	gbaMemory->activeRegion = address >> BASE_OFFSET;
 85	memory->activePrefetchCycles32 = gbaMemory->waitstatesPrefetch32[gbaMemory->activeRegion];
 86	memory->activePrefetchCycles16 = gbaMemory->waitstatesPrefetch16[gbaMemory->activeRegion];
 87	memory->activeNonseqCycles32 = gbaMemory->waitstates32[gbaMemory->activeRegion];
 88	memory->activeNonseqCycles16 = gbaMemory->waitstates16[gbaMemory->activeRegion];
 89	switch (address & ~OFFSET_MASK) {
 90	case BASE_BIOS:
 91		memory->activeRegion = gbaMemory->bios;
 92		memory->activeMask = SIZE_BIOS - 1;
 93		break;
 94	case BASE_WORKING_RAM:
 95		memory->activeRegion = gbaMemory->wram;
 96		memory->activeMask = SIZE_WORKING_RAM - 1;
 97		break;
 98	case BASE_WORKING_IRAM:
 99		memory->activeRegion = gbaMemory->iwram;
100		memory->activeMask = SIZE_WORKING_IRAM - 1;
101		break;
102	case BASE_CART0:
103	case BASE_CART0_EX:
104	case BASE_CART1:
105	case BASE_CART1_EX:
106	case BASE_CART2:
107	case BASE_CART2_EX:
108		memory->activeRegion = gbaMemory->rom;
109		memory->activeMask = SIZE_CART0 - 1;
110		break;
111	default:
112		memory->activeRegion = 0;
113		memory->activeMask = 0;
114		break;
115	}
116	gbaMemory->p->cpu.cycles += 1 + (gbaMemory->p->cpu.executionMode == MODE_ARM ? gbaMemory->waitstates32[address >> BASE_OFFSET] : gbaMemory->waitstates16[address >> BASE_OFFSET]);
117}
118
119int32_t GBALoad32(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
120	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
121	uint32_t value = 0;
122	int wait = 0;
123
124	switch (address & ~OFFSET_MASK) {
125	case BASE_BIOS:
126		break;
127	case BASE_WORKING_RAM:
128		value = gbaMemory->wram[(address & (SIZE_WORKING_RAM - 1)) >> 2];
129		wait = gbaMemory->waitstates32[REGION_WORKING_RAM];
130		break;
131	case BASE_WORKING_IRAM:
132		value = gbaMemory->iwram[(address & (SIZE_WORKING_IRAM - 1)) >> 2];
133		break;
134	case BASE_IO:
135		value = GBAIORead(gbaMemory->p, address & (SIZE_IO - 1)) | (GBAIORead(gbaMemory->p, (address & (SIZE_IO - 1)) | 2) << 16);
136		break;
137	case BASE_PALETTE_RAM:
138		value = ((int32_t*) gbaMemory->p->video.palette)[(address & (SIZE_PALETTE_RAM - 1)) >> 2];
139		break;
140	case BASE_VRAM:
141		value = ((int32_t*) gbaMemory->p->video.renderer->vram)[(address & 0x0001FFFF) >> 2];
142		break;
143	case BASE_OAM:
144		value = ((int32_t*) gbaMemory->p->video.oam.raw)[(address & (SIZE_OAM - 1)) >> 2];
145		break;
146	case BASE_CART0:
147	case BASE_CART0_EX:
148	case BASE_CART1:
149	case BASE_CART1_EX:
150	case BASE_CART2:
151	case BASE_CART2_EX:
152		wait = gbaMemory->waitstates32[address >> BASE_OFFSET];
153		if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
154			value = gbaMemory->rom[(address & (SIZE_CART0 - 1)) >> 2];
155		}
156		break;
157	case BASE_CART_SRAM:
158		break;
159	default:
160		break;
161	}
162
163
164	if (cycleCounter) {
165		*cycleCounter += 2 + wait;
166	}
167	// Unaligned 32-bit loads are "rotated" so they make some semblance of sense
168	int rotate = (address & 3) << 3;
169	return (value >> rotate) | (value << (32 - rotate));
170}
171
172uint16_t GBALoadU16(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
173	return GBALoad16(memory, address, cycleCounter);
174}
175
176int16_t GBALoad16(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
177	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
178	int16_t value = 0;
179	int wait = 0;
180
181	switch (address & ~OFFSET_MASK) {
182	case BASE_BIOS:
183		break;
184	case BASE_WORKING_RAM:
185		value = ((int16_t*) gbaMemory->wram)[(address & (SIZE_WORKING_RAM - 1)) >> 1];
186		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
187		break;
188	case BASE_WORKING_IRAM:
189		value = ((int16_t*) gbaMemory->iwram)[(address & (SIZE_WORKING_IRAM - 1)) >> 1];
190		break;
191	case BASE_IO:
192		value = GBAIORead(gbaMemory->p, address & (SIZE_IO - 1));
193		break;
194	case BASE_PALETTE_RAM:
195		value = gbaMemory->p->video.palette[(address & (SIZE_PALETTE_RAM - 1)) >> 1];
196		break;
197	case BASE_VRAM:
198		value = gbaMemory->p->video.renderer->vram[(address & 0x0001FFFF) >> 1];
199		break;
200	case BASE_OAM:
201		value = gbaMemory->p->video.oam.raw[(address & (SIZE_OAM - 1)) >> 1];
202		break;
203	case BASE_CART0:
204	case BASE_CART0_EX:
205	case BASE_CART1:
206	case BASE_CART1_EX:
207	case BASE_CART2:
208		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
209		if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
210			value = ((int16_t*) gbaMemory->rom)[(address & (SIZE_CART0 - 1)) >> 1];
211		}
212		break;
213	case BASE_CART2_EX:
214		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
215		if (gbaMemory->savedata.type == SAVEDATA_EEPROM) {
216			value = GBASavedataReadEEPROM(&gbaMemory->savedata);
217		} else if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
218			value = ((uint16_t*) gbaMemory->rom)[(address & (SIZE_CART0 - 1)) >> 1];
219		}
220		break;
221	case BASE_CART_SRAM:
222		break;
223	default:
224		break;
225	}
226
227	if (cycleCounter) {
228		*cycleCounter += 2 + wait;
229	}
230	return value;
231}
232
233uint8_t GBALoadU8(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
234	return GBALoad8(memory, address, cycleCounter);
235}
236
237int8_t GBALoad8(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
238	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
239	int8_t value = 0;
240	int wait = 0;
241
242	switch (address & ~OFFSET_MASK) {
243	case BASE_BIOS:
244		break;
245	case BASE_WORKING_RAM:
246		value = ((int8_t*) gbaMemory->wram)[address & (SIZE_WORKING_RAM - 1)];
247		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
248		break;
249	case BASE_WORKING_IRAM:
250		value = ((int8_t*) gbaMemory->iwram)[address & (SIZE_WORKING_IRAM - 1)];
251		break;
252	case BASE_IO:
253		value = (GBAIORead(gbaMemory->p, address & 0xFFFE) >> ((address & 0x0001) << 3)) & 0xFF;
254		break;
255	case BASE_PALETTE_RAM:
256		break;
257	case BASE_VRAM:
258		break;
259	case BASE_OAM:
260		break;
261	case BASE_CART0:
262	case BASE_CART0_EX:
263	case BASE_CART1:
264	case BASE_CART1_EX:
265	case BASE_CART2:
266	case BASE_CART2_EX:
267		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
268		if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
269			value = ((int8_t*) gbaMemory->rom)[address & (SIZE_CART0 - 1)];
270		}
271		break;
272	case BASE_CART_SRAM:
273		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
274		if (gbaMemory->savedata.type == SAVEDATA_NONE) {
275			GBASavedataInitSRAM(&gbaMemory->savedata);
276		}
277		value = gbaMemory->savedata.data[address & (SIZE_CART_SRAM - 1)];
278	default:
279		break;
280	}
281
282	if (cycleCounter) {
283		*cycleCounter += 2 + wait;
284	}
285	return value;
286}
287
288void GBAStore32(struct ARMMemory* memory, uint32_t address, int32_t value, int* cycleCounter) {
289	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
290	int wait = 0;
291
292	switch (address & ~OFFSET_MASK) {
293	case BASE_WORKING_RAM:
294		gbaMemory->wram[(address & (SIZE_WORKING_RAM - 1)) >> 2] = value;
295		wait = gbaMemory->waitstates32[REGION_WORKING_RAM];
296		break;
297	case BASE_WORKING_IRAM:
298		gbaMemory->iwram[(address & (SIZE_WORKING_IRAM - 1)) >> 2] = value;
299		break;
300	case BASE_IO:
301		GBAIOWrite32(gbaMemory->p, address & (SIZE_IO - 1), value);
302		break;
303	case BASE_PALETTE_RAM:
304		((int32_t*) gbaMemory->p->video.palette)[(address & (SIZE_PALETTE_RAM - 1)) >> 2] = value;
305		gbaMemory->p->video.renderer->writePalette(gbaMemory->p->video.renderer, (address & (SIZE_PALETTE_RAM - 1)) + 2, value >> 16);
306		gbaMemory->p->video.renderer->writePalette(gbaMemory->p->video.renderer, address & (SIZE_PALETTE_RAM - 1), value);
307		break;
308	case BASE_VRAM:
309		if ((address & OFFSET_MASK) < SIZE_VRAM - 2) {
310			((int32_t*) gbaMemory->p->video.renderer->vram)[(address & 0x0001FFFF) >> 2] = value;
311		}
312		break;
313	case BASE_OAM:
314		((int32_t*) gbaMemory->p->video.oam.raw)[(address & (SIZE_OAM - 1)) >> 2] = value;
315		gbaMemory->p->video.renderer->writeOAM(gbaMemory->p->video.renderer, (address & (SIZE_OAM - 4)) >> 1);
316		gbaMemory->p->video.renderer->writeOAM(gbaMemory->p->video.renderer, ((address & (SIZE_OAM - 4)) >> 1) + 1);
317		break;
318	case BASE_CART0:
319		break;
320	case BASE_CART_SRAM:
321		break;
322	default:
323		break;
324	}
325
326	if (cycleCounter) {
327		*cycleCounter += 1 + wait;
328	}
329}
330
331void GBAStore16(struct ARMMemory* memory, uint32_t address, int16_t value, int* cycleCounter) {
332	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
333	int wait = 0;
334
335	switch (address & ~OFFSET_MASK) {
336	case BASE_WORKING_RAM:
337		((int16_t*) gbaMemory->wram)[(address & (SIZE_WORKING_RAM - 1)) >> 1] = value;
338		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
339		break;
340	case BASE_WORKING_IRAM:
341		((int16_t*) gbaMemory->iwram)[(address & (SIZE_WORKING_IRAM - 1)) >> 1] = value;
342		break;
343	case BASE_IO:
344		GBAIOWrite(gbaMemory->p, address & (SIZE_IO - 1), value);
345		break;
346	case BASE_PALETTE_RAM:
347		gbaMemory->p->video.palette[(address & (SIZE_PALETTE_RAM - 1)) >> 1] = value;
348		gbaMemory->p->video.renderer->writePalette(gbaMemory->p->video.renderer, address & (SIZE_PALETTE_RAM - 1), value);
349		break;
350	case BASE_VRAM:
351		if ((address & OFFSET_MASK) < SIZE_VRAM) {
352			gbaMemory->p->video.renderer->vram[(address & 0x0001FFFF) >> 1] = value;
353		}
354		break;
355	case BASE_OAM:
356		gbaMemory->p->video.oam.raw[(address & (SIZE_OAM - 1)) >> 1] = value;
357		gbaMemory->p->video.renderer->writeOAM(gbaMemory->p->video.renderer, (address & (SIZE_OAM - 1)) >> 1);
358		break;
359	case BASE_CART0:
360		break;
361	case BASE_CART2_EX:
362		if (gbaMemory->savedata.type == SAVEDATA_NONE) {
363			GBASavedataInitEEPROM(&gbaMemory->savedata);
364		}
365		GBASavedataWriteEEPROM(&gbaMemory->savedata, value, 1);
366		break;
367	case BASE_CART_SRAM:
368		break;
369	default:
370		break;
371	}
372
373	if (cycleCounter) {
374		*cycleCounter += 1 + wait;
375	}
376}
377
378void GBAStore8(struct ARMMemory* memory, uint32_t address, int8_t value, int* cycleCounter) {
379	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
380	int wait = 0;
381
382	switch (address & ~OFFSET_MASK) {
383	case BASE_WORKING_RAM:
384		((int8_t*) gbaMemory->wram)[address & (SIZE_WORKING_RAM - 1)] = value;
385		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
386		break;
387	case BASE_WORKING_IRAM:
388		((int8_t*) gbaMemory->iwram)[address & (SIZE_WORKING_IRAM - 1)] = value;
389		break;
390	case BASE_IO:
391		GBAIOWrite8(gbaMemory->p, address & (SIZE_IO - 1), value);
392		break;
393	case BASE_PALETTE_RAM:
394		break;
395	case BASE_VRAM:
396		break;
397	case BASE_OAM:
398		break;
399	case BASE_CART0:
400		break;
401	case BASE_CART_SRAM:
402		if (gbaMemory->savedata.type == SAVEDATA_NONE) {
403			if (address == SAVEDATA_FLASH_BASE) {
404				GBASavedataInitFlash(&gbaMemory->savedata);
405			} else {
406				GBASavedataInitSRAM(&gbaMemory->savedata);
407			}
408		}
409		if (gbaMemory->savedata.type == SAVEDATA_FLASH512 || gbaMemory->savedata.type == SAVEDATA_FLASH1M) {
410			GBASavedataWriteFlash(&gbaMemory->savedata, value);
411		} else if (gbaMemory->savedata.type == SAVEDATA_SRAM) {
412			gbaMemory->savedata.data[address & (SIZE_CART_SRAM - 1)] = value;
413		}
414		wait = gbaMemory->waitstates16[REGION_CART_SRAM];
415		break;
416	default:
417		break;
418	}
419
420	if (cycleCounter) {
421		*cycleCounter += 1 + wait;
422	}
423}
424
425static int GBAWaitMultiple(struct ARMMemory* memory, uint32_t startAddress, int count) {
426	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
427	int wait = 1 + gbaMemory->waitstates32[startAddress >> BASE_OFFSET];
428	wait += (1 + gbaMemory->waitstatesSeq32[startAddress >> BASE_OFFSET]) * (count - 1);
429	return wait;
430}
431
432void GBAAdjustWaitstates(struct GBAMemory* memory, uint16_t parameters) {
433	int sram = parameters & 0x0003;
434	int ws0 = (parameters & 0x000C) >> 2;
435	int ws0seq = (parameters & 0x0010) >> 4;
436	int ws1 = (parameters & 0x0060) >> 5;
437	int ws1seq = (parameters & 0x0080) >> 7;
438	int ws2 = (parameters & 0x0300) >> 8;
439	int ws2seq = (parameters & 0x0400) >> 10;
440	int prefetch = parameters & 0x4000;
441
442	memory->waitstates16[REGION_CART_SRAM] =  GBA_ROM_WAITSTATES[sram];
443	memory->waitstatesSeq16[REGION_CART_SRAM] = GBA_ROM_WAITSTATES[sram];
444	memory->waitstates32[REGION_CART_SRAM] = 2 * GBA_ROM_WAITSTATES[sram] + 1;
445	memory->waitstatesSeq32[REGION_CART_SRAM] = 2 * GBA_ROM_WAITSTATES[sram] + 1;
446
447	memory->waitstates16[REGION_CART0] = memory->waitstates16[REGION_CART0_EX] = GBA_ROM_WAITSTATES[ws0];
448	memory->waitstates16[REGION_CART1] = memory->waitstates16[REGION_CART1_EX] = GBA_ROM_WAITSTATES[ws1];
449	memory->waitstates16[REGION_CART2] = memory->waitstates16[REGION_CART2_EX] = GBA_ROM_WAITSTATES[ws2];
450
451	memory->waitstatesSeq16[REGION_CART0] = memory->waitstatesSeq16[REGION_CART0_EX] = GBA_ROM_WAITSTATES_SEQ[ws0seq];
452	memory->waitstatesSeq16[REGION_CART1] = memory->waitstatesSeq16[REGION_CART1_EX] = GBA_ROM_WAITSTATES_SEQ[ws1seq + 2];
453	memory->waitstatesSeq16[REGION_CART2] = memory->waitstatesSeq16[REGION_CART2_EX] = GBA_ROM_WAITSTATES_SEQ[ws2seq + 4];
454
455	memory->waitstates32[REGION_CART0] = memory->waitstates32[REGION_CART0_EX] = memory->waitstates16[REGION_CART0] + 1 + memory->waitstatesSeq16[REGION_CART0];
456	memory->waitstates32[REGION_CART1] = memory->waitstates32[REGION_CART1_EX] = memory->waitstates16[REGION_CART1] + 1 + memory->waitstatesSeq16[REGION_CART1];
457	memory->waitstates32[REGION_CART2] = memory->waitstates32[REGION_CART2_EX] = memory->waitstates16[REGION_CART2] + 1 + memory->waitstatesSeq16[REGION_CART2];
458
459	memory->waitstatesSeq32[REGION_CART0] = memory->waitstatesSeq32[REGION_CART0_EX] = 2 * memory->waitstatesSeq16[REGION_CART0] + 1;
460	memory->waitstatesSeq32[REGION_CART1] = memory->waitstatesSeq32[REGION_CART1_EX] = 2 * memory->waitstatesSeq16[REGION_CART1] + 1;
461	memory->waitstatesSeq32[REGION_CART2] = memory->waitstatesSeq32[REGION_CART2_EX] = 2 * memory->waitstatesSeq16[REGION_CART2] + 1;
462
463	if (!prefetch) {
464		memory->waitstatesPrefetch16[REGION_CART0] = memory->waitstatesPrefetch16[REGION_CART0_EX] = memory->waitstatesSeq16[REGION_CART0];
465		memory->waitstatesPrefetch16[REGION_CART1] = memory->waitstatesPrefetch16[REGION_CART1_EX] = memory->waitstatesSeq16[REGION_CART1];
466		memory->waitstatesPrefetch16[REGION_CART2] = memory->waitstatesPrefetch16[REGION_CART2_EX] = memory->waitstatesSeq16[REGION_CART2];
467
468		memory->waitstatesPrefetch32[REGION_CART0] = memory->waitstatesPrefetch32[REGION_CART0_EX] = memory->waitstatesSeq32[REGION_CART0];
469		memory->waitstatesPrefetch32[REGION_CART1] = memory->waitstatesPrefetch32[REGION_CART1_EX] = memory->waitstatesSeq32[REGION_CART1];
470		memory->waitstatesPrefetch32[REGION_CART2] = memory->waitstatesPrefetch32[REGION_CART2_EX] = memory->waitstatesSeq32[REGION_CART2];
471	} else {
472		memory->waitstatesPrefetch16[REGION_CART0] = memory->waitstatesPrefetch16[REGION_CART0_EX] = 0;
473		memory->waitstatesPrefetch16[REGION_CART1] = memory->waitstatesPrefetch16[REGION_CART1_EX] = 0;
474		memory->waitstatesPrefetch16[REGION_CART2] = memory->waitstatesPrefetch16[REGION_CART2_EX] = 0;
475
476		memory->waitstatesPrefetch32[REGION_CART0] = memory->waitstatesPrefetch32[REGION_CART0_EX] = 0;
477		memory->waitstatesPrefetch32[REGION_CART1] = memory->waitstatesPrefetch32[REGION_CART1_EX] = 0;
478		memory->waitstatesPrefetch32[REGION_CART2] = memory->waitstatesPrefetch32[REGION_CART2_EX] = 0;
479	}
480
481	memory->d.activePrefetchCycles32 = memory->waitstatesPrefetch32[memory->activeRegion];
482	memory->d.activePrefetchCycles16 = memory->waitstatesPrefetch16[memory->activeRegion];
483	memory->d.activeNonseqCycles32 = memory->waitstates32[memory->activeRegion];
484	memory->d.activeNonseqCycles16 = memory->waitstates16[memory->activeRegion];
485}
486
487int32_t GBAMemoryProcessEvents(struct GBAMemory* memory, int32_t cycles) {
488	struct GBADMA* dma;
489	int32_t test = INT_MAX;
490
491	dma = &memory->dma[0];
492	dma->nextIRQ -= cycles;
493	if (dma->enable && dma->doIrq && dma->nextIRQ) {
494		if (dma->nextIRQ <= 0) {
495			dma->nextIRQ = INT_MAX;
496			GBARaiseIRQ(memory->p, IRQ_DMA0);
497		} else if (dma->nextIRQ < test) {
498			test = dma->nextIRQ;
499		}
500	}
501
502	dma = &memory->dma[1];
503	dma->nextIRQ -= cycles;
504	if (dma->enable && dma->doIrq && dma->nextIRQ) {
505		if (dma->nextIRQ <= 0) {
506			dma->nextIRQ = INT_MAX;
507			GBARaiseIRQ(memory->p, IRQ_DMA1);
508		} else if (dma->nextIRQ < test) {
509			test = dma->nextIRQ;
510		}
511	}
512
513	dma = &memory->dma[2];
514	dma->nextIRQ -= cycles;
515	if (dma->enable && dma->doIrq && dma->nextIRQ) {
516		if (dma->nextIRQ <= 0) {
517			dma->nextIRQ = INT_MAX;
518			GBARaiseIRQ(memory->p, IRQ_DMA2);
519		} else if (dma->nextIRQ < test) {
520			test = dma->nextIRQ;
521		}
522	}
523
524	dma = &memory->dma[3];
525	dma->nextIRQ -= cycles;
526	if (dma->enable && dma->doIrq && dma->nextIRQ) {
527		if (dma->nextIRQ <= 0) {
528			dma->nextIRQ = INT_MAX;
529			GBARaiseIRQ(memory->p, IRQ_DMA3);
530		} else if (dma->nextIRQ < test) {
531			test = dma->nextIRQ;
532		}
533	}
534
535	return test;
536}
537
538void GBAMemoryWriteDMASAD(struct GBAMemory* memory, int dma, uint32_t address) {
539	memory->dma[dma].source = address & 0xFFFFFFFE;
540}
541
542void GBAMemoryWriteDMADAD(struct GBAMemory* memory, int dma, uint32_t address) {
543	memory->dma[dma].dest = address & 0xFFFFFFFE;
544}
545
546void GBAMemoryWriteDMACNT_LO(struct GBAMemory* memory, int dma, uint16_t count) {
547	memory->dma[dma].count = count ? count : (dma == 3 ? 0x10000 : 0x4000);
548}
549
550uint16_t GBAMemoryWriteDMACNT_HI(struct GBAMemory* memory, int dma, uint16_t control) {
551	struct GBADMA* currentDma = &memory->dma[dma];
552	int wasEnabled = currentDma->enable;
553	currentDma->packed = control;
554	currentDma->nextIRQ = 0;
555
556	if (currentDma->drq) {
557		GBALog(memory->p, GBA_LOG_STUB, "DRQ not implemented");
558	}
559
560	if (!wasEnabled && currentDma->enable) {
561		currentDma->nextSource = currentDma->source;
562		currentDma->nextDest = currentDma->dest;
563		currentDma->nextCount = currentDma->count;
564		GBAMemoryScheduleDMA(memory, dma, currentDma);
565	}
566	// If the DMA has already occurred, this value might have changed since the function started
567	return currentDma->packed;
568};
569
570void GBAMemoryScheduleDMA(struct GBAMemory* memory, int number, struct GBADMA* info) {
571	switch (info->timing) {
572	case DMA_TIMING_NOW:
573		GBAMemoryServiceDMA(memory, number, info);
574		break;
575	case DMA_TIMING_HBLANK:
576		// Handled implicitly
577		break;
578	case DMA_TIMING_VBLANK:
579		// Handled implicitly
580		break;
581	case DMA_TIMING_CUSTOM:
582		switch (number) {
583		case 0:
584			GBALog(memory->p, GBA_LOG_WARN, "Discarding invalid DMA0 scheduling");
585			break;
586		case 1:
587		case 2:
588			//this.cpu.irq.audio.scheduleFIFODma(number, info);
589			break;
590		case 3:
591			//this.cpu.irq.video.scheduleVCaptureDma(dma, info);
592			break;
593		}
594	}
595}
596
597void GBAMemoryRunHblankDMAs(struct GBAMemory* memory) {
598	struct GBADMA* dma;
599	int i;
600	for (i = 0; i < 4; ++i) {
601		dma = &memory->dma[i];
602		if (dma->enable && dma->timing == DMA_TIMING_HBLANK) {
603			GBAMemoryServiceDMA(memory, i, dma);
604		}
605	}
606}
607
608void GBAMemoryRunVblankDMAs(struct GBAMemory* memory) {
609	struct GBADMA* dma;
610	int i;
611	for (i = 0; i < 4; ++i) {
612		dma = &memory->dma[i];
613		if (dma->enable && dma->timing == DMA_TIMING_VBLANK) {
614			GBAMemoryServiceDMA(memory, i, dma);
615		}
616	}
617}
618
619void GBAMemoryServiceDMA(struct GBAMemory* memory, int number, struct GBADMA* info) {
620	if (!info->enable) {
621		// There was a DMA scheduled that got canceled
622		return;
623	}
624
625	uint32_t width = info->width ? 4 : 2;
626	int sourceOffset = DMA_OFFSET[info->srcControl] * width;
627	int destOffset = DMA_OFFSET[info->dstControl] * width;
628	int32_t wordsRemaining = info->nextCount;
629	uint32_t source = info->nextSource;
630	uint32_t dest = info->nextDest;
631	uint32_t sourceRegion = source >> BASE_OFFSET;
632	uint32_t destRegion = dest >> BASE_OFFSET;
633
634	if (width == 4) {
635		int32_t word;
636		source &= 0xFFFFFFFC;
637		dest &= 0xFFFFFFFC;
638		while (wordsRemaining--) {
639			word = GBALoad32(&memory->d, source, 0);
640			GBAStore32(&memory->d, dest, word, 0);
641			source += sourceOffset;
642			dest += destOffset;
643		}
644	} else {
645		uint16_t word;
646		if (sourceRegion == REGION_CART2_EX && memory->savedata.type == SAVEDATA_EEPROM) {
647			while (wordsRemaining--) {
648				word = GBASavedataReadEEPROM(&memory->savedata);
649				GBAStore16(&memory->d, dest, word, 0);
650				source += sourceOffset;
651				dest += destOffset;
652			}
653		} else if (destRegion == REGION_CART2_EX) {
654			if (memory->savedata.type != SAVEDATA_EEPROM) {
655				GBASavedataInitEEPROM(&memory->savedata);
656			}
657			while (wordsRemaining) {
658				word = GBALoadU16(&memory->d, source, 0);
659				GBASavedataWriteEEPROM(&memory->savedata, word, wordsRemaining);
660				source += sourceOffset;
661				dest += destOffset;
662				--wordsRemaining;
663			}
664		} else {
665			while (wordsRemaining--) {
666				word = GBALoadU16(&memory->d, source, 0);
667				GBAStore16(&memory->d, dest, word, 0);
668				source += sourceOffset;
669				dest += destOffset;
670			}
671		}
672	}
673
674	if (info->doIrq) {
675		info->nextIRQ = memory->p->cpu.cycles + 2;
676		info->nextIRQ += (width == 4 ? memory->waitstates32[sourceRegion] + memory->waitstates32[destRegion]
677		                            : memory->waitstates16[sourceRegion] + memory->waitstates16[destRegion]);
678		info->nextIRQ += (info->count - 1) * (width == 4 ? memory->waitstatesSeq32[sourceRegion] + memory->waitstatesSeq32[destRegion]
679		                                               : memory->waitstatesSeq16[sourceRegion] + memory->waitstatesSeq16[destRegion]);
680	}
681
682	info->nextSource = source;
683	info->nextDest = dest;
684	info->nextCount = wordsRemaining;
685
686	if (!info->repeat) {
687		info->enable = 0;
688
689		// Clear the enable bit in memory
690		memory->io[(REG_DMA0CNT_HI + number * (REG_DMA1CNT_HI - REG_DMA0CNT_HI)) >> 1] &= 0x7FE0;
691	} else {
692		info->nextCount = info->count;
693		if (info->dstControl == DMA_INCREMENT_RELOAD) {
694			info->nextDest = info->dest;
695		}
696		GBAMemoryScheduleDMA(memory, number, info);
697	}
698}