all repos — mgba @ cec9e67d8824dca8cdf3745898596441ff770672

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	int i;
 47	for (i = 0; i < 16; ++i) {
 48		memory->waitstates16[i] = GBA_BASE_WAITSTATES[i];
 49		memory->waitstatesSeq16[i] = GBA_BASE_WAITSTATES_SEQ[i];
 50		memory->waitstatesPrefetch16[i] = GBA_BASE_WAITSTATES_SEQ[i];
 51		memory->waitstates32[i] = GBA_BASE_WAITSTATES_32[i];
 52		memory->waitstatesSeq32[i] = GBA_BASE_WAITSTATES_SEQ_32[i];
 53		memory->waitstatesPrefetch32[i] = GBA_BASE_WAITSTATES_SEQ_32[i];
 54	}
 55	for (; i < 256; ++i) {
 56		memory->waitstates16[i] = 0;
 57		memory->waitstatesSeq16[i] = 0;
 58		memory->waitstatesPrefetch16[i] = 0;
 59		memory->waitstates32[i] = 0;
 60		memory->waitstatesSeq32[i] = 0;
 61		memory->waitstatesPrefetch32[i] = 0;
 62	}
 63
 64	memory->activeRegion = 0;
 65	memory->d.activeRegion = 0;
 66	memory->d.activeMask = 0;
 67	memory->d.setActiveRegion = GBASetActiveRegion;
 68	memory->d.activePrefetchCycles32 = 0;
 69	memory->d.activePrefetchCycles16 = 0;
 70	memory->d.waitMultiple = GBAWaitMultiple;
 71}
 72
 73void GBAMemoryDeinit(struct GBAMemory* memory) {
 74	munmap(memory->wram, SIZE_WORKING_RAM);
 75	munmap(memory->iwram, SIZE_WORKING_IRAM);
 76	GBASavedataDeinit(&memory->savedata);
 77}
 78
 79static void GBASetActiveRegion(struct ARMMemory* memory, uint32_t address) {
 80	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
 81
 82	gbaMemory->activeRegion = address >> BASE_OFFSET;
 83	memory->activePrefetchCycles32 = gbaMemory->waitstatesPrefetch32[gbaMemory->activeRegion];
 84	memory->activePrefetchCycles16 = gbaMemory->waitstatesPrefetch16[gbaMemory->activeRegion];
 85	memory->activeNonseqCycles32 = gbaMemory->waitstates32[gbaMemory->activeRegion];
 86	memory->activeNonseqCycles16 = gbaMemory->waitstates16[gbaMemory->activeRegion];
 87	switch (address & ~OFFSET_MASK) {
 88	case BASE_BIOS:
 89		memory->activeRegion = gbaMemory->bios;
 90		memory->activeMask = SIZE_BIOS - 1;
 91		break;
 92	case BASE_WORKING_RAM:
 93		memory->activeRegion = gbaMemory->wram;
 94		memory->activeMask = SIZE_WORKING_RAM - 1;
 95		break;
 96	case BASE_WORKING_IRAM:
 97		memory->activeRegion = gbaMemory->iwram;
 98		memory->activeMask = SIZE_WORKING_IRAM - 1;
 99		break;
100	case BASE_CART0:
101	case BASE_CART0_EX:
102	case BASE_CART1:
103	case BASE_CART1_EX:
104	case BASE_CART2:
105	case BASE_CART2_EX:
106		memory->activeRegion = gbaMemory->rom;
107		memory->activeMask = SIZE_CART0 - 1;
108		break;
109	default:
110		memory->activeRegion = 0;
111		memory->activeMask = 0;
112		break;
113	}
114	gbaMemory->p->cpu.cycles += 1 + (gbaMemory->p->cpu.executionMode == MODE_ARM ? gbaMemory->waitstates32[address >> BASE_OFFSET] : gbaMemory->waitstates16[address >> BASE_OFFSET]);
115}
116
117int32_t GBALoad32(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
118	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
119	uint32_t value = 0;
120	int wait = 0;
121
122	switch (address & ~OFFSET_MASK) {
123	case BASE_BIOS:
124		break;
125	case BASE_WORKING_RAM:
126		value = gbaMemory->wram[(address & (SIZE_WORKING_RAM - 1)) >> 2];
127		wait = gbaMemory->waitstates32[REGION_WORKING_RAM];
128		break;
129	case BASE_WORKING_IRAM:
130		value = gbaMemory->iwram[(address & (SIZE_WORKING_IRAM - 1)) >> 2];
131		break;
132	case BASE_IO:
133		value = GBAIORead(gbaMemory->p, address & (SIZE_IO - 1)) | (GBAIORead(gbaMemory->p, (address & (SIZE_IO - 1)) | 2) << 16);
134		break;
135	case BASE_PALETTE_RAM:
136		value = ((int32_t*) gbaMemory->p->video.palette)[(address & (SIZE_PALETTE_RAM - 1)) >> 2];
137		break;
138	case BASE_VRAM:
139		value = ((int32_t*) gbaMemory->p->video.renderer->vram)[(address & 0x0001FFFF) >> 2];
140		break;
141	case BASE_OAM:
142		value = ((int32_t*) gbaMemory->p->video.oam.raw)[(address & (SIZE_OAM - 1)) >> 2];
143		break;
144	case BASE_CART0:
145	case BASE_CART0_EX:
146	case BASE_CART1:
147	case BASE_CART1_EX:
148	case BASE_CART2:
149	case BASE_CART2_EX:
150		wait = gbaMemory->waitstates32[address >> BASE_OFFSET];
151		if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
152			value = gbaMemory->rom[(address & (SIZE_CART0 - 1)) >> 2];
153		}
154		break;
155	case BASE_CART_SRAM:
156		break;
157	default:
158		break;
159	}
160
161
162	if (cycleCounter) {
163		*cycleCounter += 2 + wait;
164	}
165	// Unaligned 32-bit loads are "rotated" so they make some semblance of sense
166	int rotate = (address & 3) << 3;
167	return (value >> rotate) | (value << (32 - rotate));
168}
169
170uint16_t GBALoadU16(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
171	return GBALoad16(memory, address, cycleCounter);
172}
173
174int16_t GBALoad16(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
175	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
176	int16_t value = 0;
177	int wait = 0;
178
179	switch (address & ~OFFSET_MASK) {
180	case BASE_BIOS:
181		break;
182	case BASE_WORKING_RAM:
183		value = ((int16_t*) gbaMemory->wram)[(address & (SIZE_WORKING_RAM - 1)) >> 1];
184		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
185		break;
186	case BASE_WORKING_IRAM:
187		value = ((int16_t*) gbaMemory->iwram)[(address & (SIZE_WORKING_IRAM - 1)) >> 1];
188		break;
189	case BASE_IO:
190		value = GBAIORead(gbaMemory->p, address & (SIZE_IO - 1));
191		break;
192	case BASE_PALETTE_RAM:
193		value = gbaMemory->p->video.palette[(address & (SIZE_PALETTE_RAM - 1)) >> 1];
194		break;
195	case BASE_VRAM:
196		value = gbaMemory->p->video.renderer->vram[(address & 0x0001FFFF) >> 1];
197		break;
198	case BASE_OAM:
199		value = gbaMemory->p->video.oam.raw[(address & (SIZE_OAM - 1)) >> 1];
200		break;
201	case BASE_CART0:
202	case BASE_CART0_EX:
203	case BASE_CART1:
204	case BASE_CART1_EX:
205	case BASE_CART2:
206		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
207		if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
208			value = ((int16_t*) gbaMemory->rom)[(address & (SIZE_CART0 - 1)) >> 1];
209		}
210		break;
211	case BASE_CART2_EX:
212		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
213		if (gbaMemory->savedata.type == SAVEDATA_EEPROM) {
214			value = GBASavedataReadEEPROM(&gbaMemory->savedata);
215		} else if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
216			value = ((uint16_t*) gbaMemory->rom)[(address & (SIZE_CART0 - 1)) >> 1];
217		}
218		break;
219	case BASE_CART_SRAM:
220		break;
221	default:
222		break;
223	}
224
225	if (cycleCounter) {
226		*cycleCounter += 2 + wait;
227	}
228	return value;
229}
230
231uint8_t GBALoadU8(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
232	return GBALoad8(memory, address, cycleCounter);
233}
234
235int8_t GBALoad8(struct ARMMemory* memory, uint32_t address, int* cycleCounter) {
236	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
237	int8_t value = 0;
238	int wait = 0;
239
240	switch (address & ~OFFSET_MASK) {
241	case BASE_BIOS:
242		break;
243	case BASE_WORKING_RAM:
244		value = ((int8_t*) gbaMemory->wram)[address & (SIZE_WORKING_RAM - 1)];
245		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
246		break;
247	case BASE_WORKING_IRAM:
248		value = ((int8_t*) gbaMemory->iwram)[address & (SIZE_WORKING_IRAM - 1)];
249		break;
250	case BASE_IO:
251		value = (GBAIORead(gbaMemory->p, address & 0xFFFE) >> ((address & 0x0001) << 3)) & 0xFF;
252		break;
253	case BASE_PALETTE_RAM:
254		value = ((int8_t*) gbaMemory->p->video.renderer->palette)[address & (SIZE_PALETTE_RAM - 1)];
255		break;
256	case BASE_VRAM:
257		break;
258	case BASE_OAM:
259		break;
260	case BASE_CART0:
261	case BASE_CART0_EX:
262	case BASE_CART1:
263	case BASE_CART1_EX:
264	case BASE_CART2:
265	case BASE_CART2_EX:
266		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
267		if ((address & (SIZE_CART0 - 1)) < gbaMemory->romSize) {
268			value = ((int8_t*) gbaMemory->rom)[address & (SIZE_CART0 - 1)];
269		}
270		break;
271	case BASE_CART_SRAM:
272		wait = gbaMemory->waitstates16[address >> BASE_OFFSET];
273		if (gbaMemory->savedata.type == SAVEDATA_NONE) {
274			GBASavedataInit(&gbaMemory->savedata, gbaMemory->p->savefile);
275			GBASavedataInitSRAM(&gbaMemory->savedata);
276		} else if (gbaMemory->savedata.type == SAVEDATA_SRAM) {
277			value = gbaMemory->savedata.data[address & (SIZE_CART_SRAM - 1)];
278		} else if (gbaMemory->savedata.type == SAVEDATA_FLASH512 || gbaMemory->savedata.type == SAVEDATA_FLASH1M) {
279			value = GBASavedataReadFlash(&gbaMemory->savedata, address);
280		}
281	default:
282		break;
283	}
284
285	if (cycleCounter) {
286		*cycleCounter += 2 + wait;
287	}
288	return value;
289}
290
291void GBAStore32(struct ARMMemory* memory, uint32_t address, int32_t value, int* cycleCounter) {
292	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
293	int wait = 0;
294
295	switch (address & ~OFFSET_MASK) {
296	case BASE_WORKING_RAM:
297		gbaMemory->wram[(address & (SIZE_WORKING_RAM - 1)) >> 2] = value;
298		wait = gbaMemory->waitstates32[REGION_WORKING_RAM];
299		break;
300	case BASE_WORKING_IRAM:
301		gbaMemory->iwram[(address & (SIZE_WORKING_IRAM - 1)) >> 2] = value;
302		break;
303	case BASE_IO:
304		GBAIOWrite32(gbaMemory->p, address & (SIZE_IO - 1), value);
305		break;
306	case BASE_PALETTE_RAM:
307		((int32_t*) gbaMemory->p->video.palette)[(address & (SIZE_PALETTE_RAM - 1)) >> 2] = value;
308		gbaMemory->p->video.renderer->writePalette(gbaMemory->p->video.renderer, (address & (SIZE_PALETTE_RAM - 1)) + 2, value >> 16);
309		gbaMemory->p->video.renderer->writePalette(gbaMemory->p->video.renderer, address & (SIZE_PALETTE_RAM - 1), value);
310		break;
311	case BASE_VRAM:
312		if ((address & OFFSET_MASK) < SIZE_VRAM - 2) {
313			((int32_t*) gbaMemory->p->video.renderer->vram)[(address & 0x0001FFFF) >> 2] = value;
314		}
315		break;
316	case BASE_OAM:
317		((int32_t*) gbaMemory->p->video.oam.raw)[(address & (SIZE_OAM - 1)) >> 2] = value;
318		gbaMemory->p->video.renderer->writeOAM(gbaMemory->p->video.renderer, (address & (SIZE_OAM - 4)) >> 1);
319		gbaMemory->p->video.renderer->writeOAM(gbaMemory->p->video.renderer, ((address & (SIZE_OAM - 4)) >> 1) + 1);
320		break;
321	case BASE_CART0:
322		break;
323	case BASE_CART_SRAM:
324		break;
325	default:
326		break;
327	}
328
329	if (cycleCounter) {
330		*cycleCounter += 1 + wait;
331	}
332}
333
334void GBAStore16(struct ARMMemory* memory, uint32_t address, int16_t value, int* cycleCounter) {
335	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
336	int wait = 0;
337
338	switch (address & ~OFFSET_MASK) {
339	case BASE_WORKING_RAM:
340		((int16_t*) gbaMemory->wram)[(address & (SIZE_WORKING_RAM - 1)) >> 1] = value;
341		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
342		break;
343	case BASE_WORKING_IRAM:
344		((int16_t*) gbaMemory->iwram)[(address & (SIZE_WORKING_IRAM - 1)) >> 1] = value;
345		break;
346	case BASE_IO:
347		GBAIOWrite(gbaMemory->p, address & (SIZE_IO - 1), value);
348		break;
349	case BASE_PALETTE_RAM:
350		gbaMemory->p->video.palette[(address & (SIZE_PALETTE_RAM - 1)) >> 1] = value;
351		gbaMemory->p->video.renderer->writePalette(gbaMemory->p->video.renderer, address & (SIZE_PALETTE_RAM - 1), value);
352		break;
353	case BASE_VRAM:
354		if ((address & OFFSET_MASK) < SIZE_VRAM) {
355			gbaMemory->p->video.renderer->vram[(address & 0x0001FFFF) >> 1] = value;
356		}
357		break;
358	case BASE_OAM:
359		gbaMemory->p->video.oam.raw[(address & (SIZE_OAM - 1)) >> 1] = value;
360		gbaMemory->p->video.renderer->writeOAM(gbaMemory->p->video.renderer, (address & (SIZE_OAM - 1)) >> 1);
361		break;
362	case BASE_CART0:
363		break;
364	case BASE_CART2_EX:
365		if (gbaMemory->savedata.type == SAVEDATA_NONE) {
366			GBASavedataInit(&gbaMemory->savedata, gbaMemory->p->savefile);
367			GBASavedataInitEEPROM(&gbaMemory->savedata);
368		}
369		GBASavedataWriteEEPROM(&gbaMemory->savedata, value, 1);
370		break;
371	case BASE_CART_SRAM:
372		break;
373	default:
374		break;
375	}
376
377	if (cycleCounter) {
378		*cycleCounter += 1 + wait;
379	}
380}
381
382void GBAStore8(struct ARMMemory* memory, uint32_t address, int8_t value, int* cycleCounter) {
383	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
384	int wait = 0;
385
386	switch (address & ~OFFSET_MASK) {
387	case BASE_WORKING_RAM:
388		((int8_t*) gbaMemory->wram)[address & (SIZE_WORKING_RAM - 1)] = value;
389		wait = gbaMemory->waitstates16[REGION_WORKING_RAM];
390		break;
391	case BASE_WORKING_IRAM:
392		((int8_t*) gbaMemory->iwram)[address & (SIZE_WORKING_IRAM - 1)] = value;
393		break;
394	case BASE_IO:
395		GBAIOWrite8(gbaMemory->p, address & (SIZE_IO - 1), value);
396		break;
397	case BASE_PALETTE_RAM:
398		break;
399	case BASE_VRAM:
400		break;
401	case BASE_OAM:
402		break;
403	case BASE_CART0:
404		break;
405	case BASE_CART_SRAM:
406		if (gbaMemory->savedata.type == SAVEDATA_NONE) {
407			GBASavedataInit(&gbaMemory->savedata, gbaMemory->p->savefile);
408			if (address == SAVEDATA_FLASH_BASE) {
409				GBASavedataInitFlash(&gbaMemory->savedata);
410			} else {
411				GBASavedataInitSRAM(&gbaMemory->savedata);
412			}
413		}
414		if (gbaMemory->savedata.type == SAVEDATA_FLASH512 || gbaMemory->savedata.type == SAVEDATA_FLASH1M) {
415			GBASavedataWriteFlash(&gbaMemory->savedata, address, value);
416		} else if (gbaMemory->savedata.type == SAVEDATA_SRAM) {
417			gbaMemory->savedata.data[address & (SIZE_CART_SRAM - 1)] = value;
418		}
419		wait = gbaMemory->waitstates16[REGION_CART_SRAM];
420		break;
421	default:
422		break;
423	}
424
425	if (cycleCounter) {
426		*cycleCounter += 1 + wait;
427	}
428}
429
430static int GBAWaitMultiple(struct ARMMemory* memory, uint32_t startAddress, int count) {
431	struct GBAMemory* gbaMemory = (struct GBAMemory*) memory;
432	int wait = 1 + gbaMemory->waitstates32[startAddress >> BASE_OFFSET];
433	wait += (1 + gbaMemory->waitstatesSeq32[startAddress >> BASE_OFFSET]) * (count - 1);
434	return wait;
435}
436
437void GBAAdjustWaitstates(struct GBAMemory* memory, uint16_t parameters) {
438	int sram = parameters & 0x0003;
439	int ws0 = (parameters & 0x000C) >> 2;
440	int ws0seq = (parameters & 0x0010) >> 4;
441	int ws1 = (parameters & 0x0060) >> 5;
442	int ws1seq = (parameters & 0x0080) >> 7;
443	int ws2 = (parameters & 0x0300) >> 8;
444	int ws2seq = (parameters & 0x0400) >> 10;
445	int prefetch = parameters & 0x4000;
446
447	memory->waitstates16[REGION_CART_SRAM] =  GBA_ROM_WAITSTATES[sram];
448	memory->waitstatesSeq16[REGION_CART_SRAM] = GBA_ROM_WAITSTATES[sram];
449	memory->waitstates32[REGION_CART_SRAM] = 2 * GBA_ROM_WAITSTATES[sram] + 1;
450	memory->waitstatesSeq32[REGION_CART_SRAM] = 2 * GBA_ROM_WAITSTATES[sram] + 1;
451
452	memory->waitstates16[REGION_CART0] = memory->waitstates16[REGION_CART0_EX] = GBA_ROM_WAITSTATES[ws0];
453	memory->waitstates16[REGION_CART1] = memory->waitstates16[REGION_CART1_EX] = GBA_ROM_WAITSTATES[ws1];
454	memory->waitstates16[REGION_CART2] = memory->waitstates16[REGION_CART2_EX] = GBA_ROM_WAITSTATES[ws2];
455
456	memory->waitstatesSeq16[REGION_CART0] = memory->waitstatesSeq16[REGION_CART0_EX] = GBA_ROM_WAITSTATES_SEQ[ws0seq];
457	memory->waitstatesSeq16[REGION_CART1] = memory->waitstatesSeq16[REGION_CART1_EX] = GBA_ROM_WAITSTATES_SEQ[ws1seq + 2];
458	memory->waitstatesSeq16[REGION_CART2] = memory->waitstatesSeq16[REGION_CART2_EX] = GBA_ROM_WAITSTATES_SEQ[ws2seq + 4];
459
460	memory->waitstates32[REGION_CART0] = memory->waitstates32[REGION_CART0_EX] = memory->waitstates16[REGION_CART0] + 1 + memory->waitstatesSeq16[REGION_CART0];
461	memory->waitstates32[REGION_CART1] = memory->waitstates32[REGION_CART1_EX] = memory->waitstates16[REGION_CART1] + 1 + memory->waitstatesSeq16[REGION_CART1];
462	memory->waitstates32[REGION_CART2] = memory->waitstates32[REGION_CART2_EX] = memory->waitstates16[REGION_CART2] + 1 + memory->waitstatesSeq16[REGION_CART2];
463
464	memory->waitstatesSeq32[REGION_CART0] = memory->waitstatesSeq32[REGION_CART0_EX] = 2 * memory->waitstatesSeq16[REGION_CART0] + 1;
465	memory->waitstatesSeq32[REGION_CART1] = memory->waitstatesSeq32[REGION_CART1_EX] = 2 * memory->waitstatesSeq16[REGION_CART1] + 1;
466	memory->waitstatesSeq32[REGION_CART2] = memory->waitstatesSeq32[REGION_CART2_EX] = 2 * memory->waitstatesSeq16[REGION_CART2] + 1;
467
468	if (!prefetch) {
469		memory->waitstatesPrefetch16[REGION_CART0] = memory->waitstatesPrefetch16[REGION_CART0_EX] = memory->waitstatesSeq16[REGION_CART0];
470		memory->waitstatesPrefetch16[REGION_CART1] = memory->waitstatesPrefetch16[REGION_CART1_EX] = memory->waitstatesSeq16[REGION_CART1];
471		memory->waitstatesPrefetch16[REGION_CART2] = memory->waitstatesPrefetch16[REGION_CART2_EX] = memory->waitstatesSeq16[REGION_CART2];
472
473		memory->waitstatesPrefetch32[REGION_CART0] = memory->waitstatesPrefetch32[REGION_CART0_EX] = memory->waitstatesSeq32[REGION_CART0];
474		memory->waitstatesPrefetch32[REGION_CART1] = memory->waitstatesPrefetch32[REGION_CART1_EX] = memory->waitstatesSeq32[REGION_CART1];
475		memory->waitstatesPrefetch32[REGION_CART2] = memory->waitstatesPrefetch32[REGION_CART2_EX] = memory->waitstatesSeq32[REGION_CART2];
476	} else {
477		memory->waitstatesPrefetch16[REGION_CART0] = memory->waitstatesPrefetch16[REGION_CART0_EX] = 0;
478		memory->waitstatesPrefetch16[REGION_CART1] = memory->waitstatesPrefetch16[REGION_CART1_EX] = 0;
479		memory->waitstatesPrefetch16[REGION_CART2] = memory->waitstatesPrefetch16[REGION_CART2_EX] = 0;
480
481		memory->waitstatesPrefetch32[REGION_CART0] = memory->waitstatesPrefetch32[REGION_CART0_EX] = 0;
482		memory->waitstatesPrefetch32[REGION_CART1] = memory->waitstatesPrefetch32[REGION_CART1_EX] = 0;
483		memory->waitstatesPrefetch32[REGION_CART2] = memory->waitstatesPrefetch32[REGION_CART2_EX] = 0;
484	}
485
486	memory->d.activePrefetchCycles32 = memory->waitstatesPrefetch32[memory->activeRegion];
487	memory->d.activePrefetchCycles16 = memory->waitstatesPrefetch16[memory->activeRegion];
488	memory->d.activeNonseqCycles32 = memory->waitstates32[memory->activeRegion];
489	memory->d.activeNonseqCycles16 = memory->waitstates16[memory->activeRegion];
490}
491
492int32_t GBAMemoryProcessEvents(struct GBAMemory* memory, int32_t cycles) {
493	struct GBADMA* dma;
494	int32_t test = INT_MAX;
495
496	dma = &memory->dma[0];
497	dma->nextIRQ -= cycles;
498	if (dma->enable && dma->doIrq && dma->nextIRQ) {
499		if (dma->nextIRQ <= 0) {
500			dma->nextIRQ = INT_MAX;
501			GBARaiseIRQ(memory->p, IRQ_DMA0);
502		} else if (dma->nextIRQ < test) {
503			test = dma->nextIRQ;
504		}
505	}
506
507	dma = &memory->dma[1];
508	dma->nextIRQ -= cycles;
509	if (dma->enable && dma->doIrq && dma->nextIRQ) {
510		if (dma->nextIRQ <= 0) {
511			dma->nextIRQ = INT_MAX;
512			GBARaiseIRQ(memory->p, IRQ_DMA1);
513		} else if (dma->nextIRQ < test) {
514			test = dma->nextIRQ;
515		}
516	}
517
518	dma = &memory->dma[2];
519	dma->nextIRQ -= cycles;
520	if (dma->enable && dma->doIrq && dma->nextIRQ) {
521		if (dma->nextIRQ <= 0) {
522			dma->nextIRQ = INT_MAX;
523			GBARaiseIRQ(memory->p, IRQ_DMA2);
524		} else if (dma->nextIRQ < test) {
525			test = dma->nextIRQ;
526		}
527	}
528
529	dma = &memory->dma[3];
530	dma->nextIRQ -= cycles;
531	if (dma->enable && dma->doIrq && dma->nextIRQ) {
532		if (dma->nextIRQ <= 0) {
533			dma->nextIRQ = INT_MAX;
534			GBARaiseIRQ(memory->p, IRQ_DMA3);
535		} else if (dma->nextIRQ < test) {
536			test = dma->nextIRQ;
537		}
538	}
539
540	return test;
541}
542
543void GBAMemoryWriteDMASAD(struct GBAMemory* memory, int dma, uint32_t address) {
544	memory->dma[dma].source = address & 0xFFFFFFFE;
545}
546
547void GBAMemoryWriteDMADAD(struct GBAMemory* memory, int dma, uint32_t address) {
548	memory->dma[dma].dest = address & 0xFFFFFFFE;
549}
550
551void GBAMemoryWriteDMACNT_LO(struct GBAMemory* memory, int dma, uint16_t count) {
552	memory->dma[dma].count = count ? count : (dma == 3 ? 0x10000 : 0x4000);
553}
554
555uint16_t GBAMemoryWriteDMACNT_HI(struct GBAMemory* memory, int dma, uint16_t control) {
556	struct GBADMA* currentDma = &memory->dma[dma];
557	int wasEnabled = currentDma->enable;
558	currentDma->packed = control;
559	currentDma->nextIRQ = 0;
560
561	if (currentDma->drq) {
562		GBALog(memory->p, GBA_LOG_STUB, "DRQ not implemented");
563	}
564
565	if (!wasEnabled && currentDma->enable) {
566		currentDma->nextSource = currentDma->source;
567		currentDma->nextDest = currentDma->dest;
568		currentDma->nextCount = currentDma->count;
569		GBAMemoryScheduleDMA(memory, dma, currentDma);
570	}
571	// If the DMA has already occurred, this value might have changed since the function started
572	return currentDma->packed;
573};
574
575void GBAMemoryScheduleDMA(struct GBAMemory* memory, int number, struct GBADMA* info) {
576	switch (info->timing) {
577	case DMA_TIMING_NOW:
578		GBAMemoryServiceDMA(memory, number, info);
579		break;
580	case DMA_TIMING_HBLANK:
581		// Handled implicitly
582		break;
583	case DMA_TIMING_VBLANK:
584		// Handled implicitly
585		break;
586	case DMA_TIMING_CUSTOM:
587		switch (number) {
588		case 0:
589			GBALog(memory->p, GBA_LOG_WARN, "Discarding invalid DMA0 scheduling");
590			break;
591		case 1:
592		case 2:
593			//this.cpu.irq.audio.scheduleFIFODma(number, info);
594			break;
595		case 3:
596			//this.cpu.irq.video.scheduleVCaptureDma(dma, info);
597			break;
598		}
599	}
600}
601
602void GBAMemoryRunHblankDMAs(struct GBAMemory* memory) {
603	struct GBADMA* dma;
604	int i;
605	for (i = 0; i < 4; ++i) {
606		dma = &memory->dma[i];
607		if (dma->enable && dma->timing == DMA_TIMING_HBLANK) {
608			GBAMemoryServiceDMA(memory, i, dma);
609		}
610	}
611}
612
613void GBAMemoryRunVblankDMAs(struct GBAMemory* memory) {
614	struct GBADMA* dma;
615	int i;
616	for (i = 0; i < 4; ++i) {
617		dma = &memory->dma[i];
618		if (dma->enable && dma->timing == DMA_TIMING_VBLANK) {
619			GBAMemoryServiceDMA(memory, i, dma);
620		}
621	}
622}
623
624void GBAMemoryServiceDMA(struct GBAMemory* memory, int number, struct GBADMA* info) {
625	if (!info->enable) {
626		// There was a DMA scheduled that got canceled
627		return;
628	}
629
630	uint32_t width = info->width ? 4 : 2;
631	int sourceOffset = DMA_OFFSET[info->srcControl] * width;
632	int destOffset = DMA_OFFSET[info->dstControl] * width;
633	int32_t wordsRemaining = info->nextCount;
634	uint32_t source = info->nextSource;
635	uint32_t dest = info->nextDest;
636	uint32_t sourceRegion = source >> BASE_OFFSET;
637	uint32_t destRegion = dest >> BASE_OFFSET;
638
639	if (width == 4) {
640		int32_t word;
641		source &= 0xFFFFFFFC;
642		dest &= 0xFFFFFFFC;
643		while (wordsRemaining--) {
644			word = GBALoad32(&memory->d, source, 0);
645			GBAStore32(&memory->d, dest, word, 0);
646			source += sourceOffset;
647			dest += destOffset;
648		}
649	} else {
650		uint16_t word;
651		if (sourceRegion == REGION_CART2_EX && memory->savedata.type == SAVEDATA_EEPROM) {
652			while (wordsRemaining--) {
653				word = GBASavedataReadEEPROM(&memory->savedata);
654				GBAStore16(&memory->d, dest, word, 0);
655				source += sourceOffset;
656				dest += destOffset;
657			}
658		} else if (destRegion == REGION_CART2_EX) {
659			if (memory->savedata.type != SAVEDATA_EEPROM) {
660				GBASavedataInitEEPROM(&memory->savedata);
661			}
662			while (wordsRemaining) {
663				word = GBALoadU16(&memory->d, source, 0);
664				GBASavedataWriteEEPROM(&memory->savedata, word, wordsRemaining);
665				source += sourceOffset;
666				dest += destOffset;
667				--wordsRemaining;
668			}
669		} else {
670			while (wordsRemaining--) {
671				word = GBALoadU16(&memory->d, source, 0);
672				GBAStore16(&memory->d, dest, word, 0);
673				source += sourceOffset;
674				dest += destOffset;
675			}
676		}
677	}
678
679	if (info->doIrq) {
680		info->nextIRQ = memory->p->cpu.cycles + 2;
681		info->nextIRQ += (width == 4 ? memory->waitstates32[sourceRegion] + memory->waitstates32[destRegion]
682		                            : memory->waitstates16[sourceRegion] + memory->waitstates16[destRegion]);
683		info->nextIRQ += (info->count - 1) * (width == 4 ? memory->waitstatesSeq32[sourceRegion] + memory->waitstatesSeq32[destRegion]
684		                                               : memory->waitstatesSeq16[sourceRegion] + memory->waitstatesSeq16[destRegion]);
685	}
686
687	info->nextSource = source;
688	info->nextDest = dest;
689	info->nextCount = wordsRemaining;
690
691	if (!info->repeat) {
692		info->enable = 0;
693
694		// Clear the enable bit in memory
695		memory->io[(REG_DMA0CNT_HI + number * (REG_DMA1CNT_HI - REG_DMA0CNT_HI)) >> 1] &= 0x7FE0;
696	} else {
697		info->nextCount = info->count;
698		if (info->dstControl == DMA_INCREMENT_RELOAD) {
699			info->nextDest = info->dest;
700		}
701		GBAMemoryScheduleDMA(memory, number, info);
702	}
703}