src/gb/memory.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/memory.h>
7
8#include <mgba/core/interface.h>
9#include <mgba/internal/gb/gb.h>
10#include <mgba/internal/gb/io.h>
11#include <mgba/internal/gb/mbc.h>
12#include <mgba/internal/gb/serialize.h>
13#include <mgba/internal/sm83/sm83.h>
14
15#include <mgba-util/memory.h>
16
17mLOG_DEFINE_CATEGORY(GB_MEM, "GB Memory", "gb.memory");
18
19static const uint8_t _yankBuffer[] = { 0xFF };
20
21enum GBBus {
22 GB_BUS_CPU,
23 GB_BUS_MAIN,
24 GB_BUS_VRAM,
25 GB_BUS_RAM
26};
27
28static const enum GBBus _oamBlockDMG[] = {
29 GB_BUS_MAIN, // 0x0000
30 GB_BUS_MAIN, // 0x2000
31 GB_BUS_MAIN, // 0x4000
32 GB_BUS_MAIN, // 0x6000
33 GB_BUS_VRAM, // 0x8000
34 GB_BUS_MAIN, // 0xA000
35 GB_BUS_MAIN, // 0xC000
36 GB_BUS_CPU, // 0xE000
37};
38
39static const enum GBBus _oamBlockCGB[] = {
40 GB_BUS_MAIN, // 0x0000
41 GB_BUS_MAIN, // 0x2000
42 GB_BUS_MAIN, // 0x4000
43 GB_BUS_MAIN, // 0x6000
44 GB_BUS_VRAM, // 0x8000
45 GB_BUS_MAIN, // 0xA000
46 GB_BUS_RAM, // 0xC000
47 GB_BUS_CPU // 0xE000
48};
49
50static const uint8_t _blockedRegion[1] = { 0xFF };
51
52static void _pristineCow(struct GB* gba);
53
54static uint8_t GBFastLoad8(struct SM83Core* cpu, uint16_t address) {
55 if (UNLIKELY(address >= cpu->memory.activeRegionEnd)) {
56 cpu->memory.setActiveRegion(cpu, address);
57 return cpu->memory.cpuLoad8(cpu, address);
58 }
59 return cpu->memory.activeRegion[address & cpu->memory.activeMask];
60}
61
62static void GBSetActiveRegion(struct SM83Core* cpu, uint16_t address) {
63 struct GB* gb = (struct GB*) cpu->master;
64 struct GBMemory* memory = &gb->memory;
65 switch (address >> 12) {
66 case GB_REGION_CART_BANK0:
67 case GB_REGION_CART_BANK0 + 1:
68 case GB_REGION_CART_BANK0 + 2:
69 case GB_REGION_CART_BANK0 + 3:
70 cpu->memory.cpuLoad8 = GBFastLoad8;
71 cpu->memory.activeRegion = memory->romBase;
72 cpu->memory.activeRegionEnd = GB_BASE_CART_BANK1;
73 cpu->memory.activeMask = GB_SIZE_CART_BANK0 - 1;
74 if (gb->memory.romSize < GB_SIZE_CART_BANK0) {
75 if (address >= gb->memory.romSize) {
76 cpu->memory.activeRegion = _yankBuffer;
77 cpu->memory.activeMask = 0;
78 } else {
79 cpu->memory.activeRegionEnd = gb->memory.romSize;
80 }
81 }
82 break;
83 case GB_REGION_CART_BANK1:
84 case GB_REGION_CART_BANK1 + 1:
85 case GB_REGION_CART_BANK1 + 2:
86 case GB_REGION_CART_BANK1 + 3:
87 if ((gb->memory.mbcType & GB_UNL_BBD) == GB_UNL_BBD) {
88 cpu->memory.cpuLoad8 = GBLoad8;
89 break;
90 }
91 cpu->memory.cpuLoad8 = GBFastLoad8;
92 if (gb->memory.mbcType != GB_MBC6) {
93 cpu->memory.activeRegion = memory->romBank;
94 cpu->memory.activeRegionEnd = GB_BASE_VRAM;
95 cpu->memory.activeMask = GB_SIZE_CART_BANK0 - 1;
96 } else {
97 cpu->memory.activeMask = GB_SIZE_CART_HALFBANK - 1;
98 if (address & 0x2000) {
99 cpu->memory.activeRegion = memory->mbcState.mbc6.romBank1;
100 cpu->memory.activeRegionEnd = GB_BASE_VRAM;
101 } else {
102 cpu->memory.activeRegion = memory->romBank;
103 cpu->memory.activeRegionEnd = GB_BASE_CART_BANK1 + 0x2000;
104 }
105 }
106 if (gb->memory.romSize < GB_SIZE_CART_BANK0 * 2) {
107 if (address >= gb->memory.romSize) {
108 cpu->memory.activeRegion = _yankBuffer;
109 cpu->memory.activeMask = 0;
110 } else {
111 cpu->memory.activeRegionEnd = gb->memory.romSize;
112 }
113 }
114 break;
115 default:
116 cpu->memory.cpuLoad8 = GBLoad8;
117 break;
118 }
119 if (gb->memory.dmaRemaining) {
120 const enum GBBus* block = gb->model < GB_MODEL_CGB ? _oamBlockDMG : _oamBlockCGB;
121 enum GBBus dmaBus = block[memory->dmaSource >> 13];
122 enum GBBus accessBus = block[address >> 13];
123 if ((dmaBus != GB_BUS_CPU && dmaBus == accessBus) || (address >= GB_BASE_OAM && address < GB_BASE_UNUSABLE)) {
124 cpu->memory.activeRegion = _blockedRegion;
125 cpu->memory.activeMask = 0;
126 }
127 }
128}
129
130static void _GBMemoryDMAService(struct mTiming* timing, void* context, uint32_t cyclesLate);
131static void _GBMemoryHDMAService(struct mTiming* timing, void* context, uint32_t cyclesLate);
132
133void GBMemoryInit(struct GB* gb) {
134 struct SM83Core* cpu = gb->cpu;
135 cpu->memory.cpuLoad8 = GBLoad8;
136 cpu->memory.load8 = GBLoad8;
137 cpu->memory.store8 = GBStore8;
138 cpu->memory.currentSegment = GBCurrentSegment;
139 cpu->memory.setActiveRegion = GBSetActiveRegion;
140
141 gb->memory.wram = 0;
142 gb->memory.wramBank = 0;
143 gb->memory.rom = 0;
144 gb->memory.romBank = 0;
145 gb->memory.romSize = 0;
146 gb->memory.sram = 0;
147 gb->memory.mbcType = GB_MBC_AUTODETECT;
148 gb->memory.mbcRead = NULL;
149 gb->memory.mbcWrite = NULL;
150
151 gb->memory.rtc = NULL;
152 gb->memory.rotation = NULL;
153 gb->memory.rumble = NULL;
154 gb->memory.cam = NULL;
155
156 GBIOInit(gb);
157}
158
159void GBMemoryDeinit(struct GB* gb) {
160 mappedMemoryFree(gb->memory.wram, GB_SIZE_WORKING_RAM);
161 if (gb->memory.rom) {
162 mappedMemoryFree(gb->memory.rom, gb->memory.romSize);
163 }
164}
165
166void GBMemoryReset(struct GB* gb) {
167 if (gb->memory.wram) {
168 mappedMemoryFree(gb->memory.wram, GB_SIZE_WORKING_RAM);
169 }
170 gb->memory.wram = anonymousMemoryMap(GB_SIZE_WORKING_RAM);
171 if (gb->model >= GB_MODEL_CGB) {
172 uint32_t* base = (uint32_t*) gb->memory.wram;
173 size_t i;
174 uint32_t pattern = 0;
175 for (i = 0; i < GB_SIZE_WORKING_RAM / 4; i += 4) {
176 if ((i & 0x1FF) == 0) {
177 pattern = ~pattern;
178 }
179 base[i + 0] = pattern;
180 base[i + 1] = pattern;
181 base[i + 2] = ~pattern;
182 base[i + 3] = ~pattern;
183 }
184 }
185 GBMemorySwitchWramBank(&gb->memory, 1);
186 gb->memory.romBank = &gb->memory.rom[GB_SIZE_CART_BANK0];
187 gb->memory.currentBank = 1;
188 gb->memory.sramCurrentBank = 0;
189
190 gb->memory.ime = false;
191 gb->memory.ie = 0;
192
193 gb->memory.dmaRemaining = 0;
194 gb->memory.dmaSource = 0;
195 gb->memory.dmaDest = 0;
196 gb->memory.hdmaRemaining = 0;
197 gb->memory.hdmaSource = 0;
198 gb->memory.hdmaDest = 0;
199 gb->memory.isHdma = false;
200
201
202 gb->memory.dmaEvent.context = gb;
203 gb->memory.dmaEvent.name = "GB DMA";
204 gb->memory.dmaEvent.callback = _GBMemoryDMAService;
205 gb->memory.dmaEvent.priority = 0x40;
206 gb->memory.hdmaEvent.context = gb;
207 gb->memory.hdmaEvent.name = "GB HDMA";
208 gb->memory.hdmaEvent.callback = _GBMemoryHDMAService;
209 gb->memory.hdmaEvent.priority = 0x41;
210
211 memset(&gb->memory.hram, 0, sizeof(gb->memory.hram));
212
213 memset(&gb->memory.mbcState, 0, sizeof(gb->memory.mbcState));
214 GBMBCInit(gb);
215 switch (gb->memory.mbcType) {
216 case GB_MBC1:
217 gb->memory.mbcState.mbc1.mode = 0;
218 gb->memory.mbcState.mbc1.bankLo = 1;
219 break;
220 case GB_MBC6:
221 GBMBCSwitchHalfBank(gb, 0, 2);
222 GBMBCSwitchHalfBank(gb, 1, 3);
223 gb->memory.mbcState.mbc6.sramAccess = false;
224 GBMBCSwitchSramHalfBank(gb, 0, 0);
225 GBMBCSwitchSramHalfBank(gb, 0, 1);
226 break;
227 case GB_MMM01:
228 GBMBCSwitchBank0(gb, gb->memory.romSize / GB_SIZE_CART_BANK0 - 2);
229 GBMBCSwitchBank(gb, gb->memory.romSize / GB_SIZE_CART_BANK0 - 1);
230 break;
231 default:
232 break;
233 }
234 gb->memory.sramBank = gb->memory.sram;
235
236 if (!gb->memory.wram) {
237 GBMemoryDeinit(gb);
238 }
239}
240
241void GBMemorySwitchWramBank(struct GBMemory* memory, int bank) {
242 bank &= 7;
243 if (!bank) {
244 bank = 1;
245 }
246 memory->wramBank = &memory->wram[GB_SIZE_WORKING_RAM_BANK0 * bank];
247 memory->wramCurrentBank = bank;
248}
249
250uint8_t GBLoad8(struct SM83Core* cpu, uint16_t address) {
251 struct GB* gb = (struct GB*) cpu->master;
252 struct GBMemory* memory = &gb->memory;
253 if (gb->memory.dmaRemaining) {
254 const enum GBBus* block = gb->model < GB_MODEL_CGB ? _oamBlockDMG : _oamBlockCGB;
255 enum GBBus dmaBus = block[memory->dmaSource >> 13];
256 enum GBBus accessBus = block[address >> 13];
257 if (dmaBus != GB_BUS_CPU && dmaBus == accessBus) {
258 return 0xFF;
259 }
260 if (address >= GB_BASE_OAM && address < GB_BASE_IO) {
261 return 0xFF;
262 }
263 }
264 switch (address >> 12) {
265 case GB_REGION_CART_BANK0:
266 case GB_REGION_CART_BANK0 + 1:
267 case GB_REGION_CART_BANK0 + 2:
268 case GB_REGION_CART_BANK0 + 3:
269 if (address >= memory->romSize) {
270 return 0xFF;
271 }
272 return memory->romBase[address & (GB_SIZE_CART_BANK0 - 1)];
273 case GB_REGION_CART_BANK1 + 2:
274 case GB_REGION_CART_BANK1 + 3:
275 if (memory->mbcType == GB_MBC6) {
276 return memory->mbcState.mbc6.romBank1[address & (GB_SIZE_CART_HALFBANK - 1)];
277 }
278 // Fall through
279 case GB_REGION_CART_BANK1:
280 case GB_REGION_CART_BANK1 + 1:
281 if (address >= memory->romSize) {
282 return 0xFF;
283 }
284 if ((memory->mbcType & GB_UNL_BBD) == GB_UNL_BBD) {
285 return memory->mbcRead(memory, address);
286 }
287 return memory->romBank[address & (GB_SIZE_CART_BANK0 - 1)];
288 case GB_REGION_VRAM:
289 case GB_REGION_VRAM + 1:
290 if (gb->video.mode != 3) {
291 return gb->video.vramBank[address & (GB_SIZE_VRAM_BANK0 - 1)];
292 }
293 return 0xFF;
294 case GB_REGION_EXTERNAL_RAM:
295 case GB_REGION_EXTERNAL_RAM + 1:
296 if (memory->rtcAccess) {
297 return memory->rtcRegs[memory->activeRtcReg];
298 } else if (memory->mbcRead) {
299 return memory->mbcRead(memory, address);
300 } else if (memory->sramAccess && memory->sram) {
301 return memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)];
302 } else if (memory->mbcType == GB_HuC3) {
303 return 0x01; // TODO: Is this supposed to be the current SRAM bank?
304 }
305 return 0xFF;
306 case GB_REGION_WORKING_RAM_BANK0:
307 case GB_REGION_WORKING_RAM_BANK0 + 2:
308 return memory->wram[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
309 case GB_REGION_WORKING_RAM_BANK1:
310 return memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
311 default:
312 if (address < GB_BASE_OAM) {
313 return memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
314 }
315 if (address < GB_BASE_UNUSABLE) {
316 if (gb->video.mode < 2) {
317 return gb->video.oam.raw[address & 0xFF];
318 }
319 return 0xFF;
320 }
321 if (address < GB_BASE_IO) {
322 mLOG(GB_MEM, GAME_ERROR, "Attempt to read from unusable memory: %04X", address);
323 return 0xFF;
324 }
325 if (address < GB_BASE_HRAM) {
326 return GBIORead(gb, address & (GB_SIZE_IO - 1));
327 }
328 if (address < GB_BASE_IE) {
329 return memory->hram[address & GB_SIZE_HRAM];
330 }
331 return GBIORead(gb, GB_REG_IE);
332 }
333}
334
335void GBStore8(struct SM83Core* cpu, uint16_t address, int8_t value) {
336 struct GB* gb = (struct GB*) cpu->master;
337 struct GBMemory* memory = &gb->memory;
338 if (gb->memory.dmaRemaining) {
339 const enum GBBus* block = gb->model < GB_MODEL_CGB ? _oamBlockDMG : _oamBlockCGB;
340 enum GBBus dmaBus = block[memory->dmaSource >> 13];
341 enum GBBus accessBus = block[address >> 13];
342 if (dmaBus != GB_BUS_CPU && dmaBus == accessBus) {
343 return;
344 }
345 if (address >= GB_BASE_OAM && address < GB_BASE_UNUSABLE) {
346 return;
347 }
348 }
349 switch (address >> 12) {
350 case GB_REGION_CART_BANK0:
351 case GB_REGION_CART_BANK0 + 1:
352 case GB_REGION_CART_BANK0 + 2:
353 case GB_REGION_CART_BANK0 + 3:
354 case GB_REGION_CART_BANK1:
355 case GB_REGION_CART_BANK1 + 1:
356 case GB_REGION_CART_BANK1 + 2:
357 case GB_REGION_CART_BANK1 + 3:
358 memory->mbcWrite(gb, address, value);
359 cpu->memory.setActiveRegion(cpu, cpu->pc);
360 return;
361 case GB_REGION_VRAM:
362 case GB_REGION_VRAM + 1:
363 if (gb->video.mode != 3) {
364 gb->video.renderer->writeVRAM(gb->video.renderer, (address & (GB_SIZE_VRAM_BANK0 - 1)) | (GB_SIZE_VRAM_BANK0 * gb->video.vramCurrentBank));
365 gb->video.vramBank[address & (GB_SIZE_VRAM_BANK0 - 1)] = value;
366 }
367 return;
368 case GB_REGION_EXTERNAL_RAM:
369 case GB_REGION_EXTERNAL_RAM + 1:
370 if (memory->rtcAccess) {
371 memory->rtcRegs[memory->activeRtcReg] = value;
372 } else if (memory->sramAccess && memory->sram && memory->directSramAccess) {
373 memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)] = value;
374 } else {
375 memory->mbcWrite(gb, address, value);
376 }
377 gb->sramDirty |= GB_SRAM_DIRT_NEW;
378 return;
379 case GB_REGION_WORKING_RAM_BANK0:
380 case GB_REGION_WORKING_RAM_BANK0 + 2:
381 memory->wram[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)] = value;
382 return;
383 case GB_REGION_WORKING_RAM_BANK1:
384 memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)] = value;
385 return;
386 default:
387 if (address < GB_BASE_OAM) {
388 memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)] = value;
389 } else if (address < GB_BASE_UNUSABLE) {
390 if (gb->video.mode < 2) {
391 gb->video.oam.raw[address & 0xFF] = value;
392 gb->video.renderer->writeOAM(gb->video.renderer, address & 0xFF);
393 }
394 } else if (address < GB_BASE_IO) {
395 mLOG(GB_MEM, GAME_ERROR, "Attempt to write to unusable memory: %04X:%02X", address, value);
396 } else if (address < GB_BASE_HRAM) {
397 GBIOWrite(gb, address & (GB_SIZE_IO - 1), value);
398 } else if (address < GB_BASE_IE) {
399 memory->hram[address & GB_SIZE_HRAM] = value;
400 } else {
401 GBIOWrite(gb, GB_REG_IE, value);
402 }
403 }
404}
405
406int GBCurrentSegment(struct SM83Core* cpu, uint16_t address) {
407 struct GB* gb = (struct GB*) cpu->master;
408 struct GBMemory* memory = &gb->memory;
409 switch (address >> 12) {
410 case GB_REGION_CART_BANK0:
411 case GB_REGION_CART_BANK0 + 1:
412 case GB_REGION_CART_BANK0 + 2:
413 case GB_REGION_CART_BANK0 + 3:
414 return 0;
415 case GB_REGION_CART_BANK1:
416 case GB_REGION_CART_BANK1 + 1:
417 case GB_REGION_CART_BANK1 + 2:
418 case GB_REGION_CART_BANK1 + 3:
419 return memory->currentBank;
420 case GB_REGION_VRAM:
421 case GB_REGION_VRAM + 1:
422 return gb->video.vramCurrentBank;
423 case GB_REGION_EXTERNAL_RAM:
424 case GB_REGION_EXTERNAL_RAM + 1:
425 return memory->sramCurrentBank;
426 case GB_REGION_WORKING_RAM_BANK0:
427 case GB_REGION_WORKING_RAM_BANK0 + 2:
428 return 0;
429 case GB_REGION_WORKING_RAM_BANK1:
430 return memory->wramCurrentBank;
431 default:
432 return 0;
433 }
434}
435
436uint8_t GBView8(struct SM83Core* cpu, uint16_t address, int segment) {
437 struct GB* gb = (struct GB*) cpu->master;
438 struct GBMemory* memory = &gb->memory;
439 switch (address >> 12) {
440 case GB_REGION_CART_BANK0:
441 case GB_REGION_CART_BANK0 + 1:
442 case GB_REGION_CART_BANK0 + 2:
443 case GB_REGION_CART_BANK0 + 3:
444 return memory->romBase[address & (GB_SIZE_CART_BANK0 - 1)];
445 case GB_REGION_CART_BANK1:
446 case GB_REGION_CART_BANK1 + 1:
447 case GB_REGION_CART_BANK1 + 2:
448 case GB_REGION_CART_BANK1 + 3:
449 if (segment < 0) {
450 return memory->romBank[address & (GB_SIZE_CART_BANK0 - 1)];
451 } else if ((size_t) segment * GB_SIZE_CART_BANK0 < memory->romSize) {
452 return memory->rom[(address & (GB_SIZE_CART_BANK0 - 1)) + segment * GB_SIZE_CART_BANK0];
453 } else {
454 return 0xFF;
455 }
456 case GB_REGION_VRAM:
457 case GB_REGION_VRAM + 1:
458 if (segment < 0) {
459 return gb->video.vramBank[address & (GB_SIZE_VRAM_BANK0 - 1)];
460 } else if (segment < 2) {
461 return gb->video.vram[(address & (GB_SIZE_VRAM_BANK0 - 1)) + segment *GB_SIZE_VRAM_BANK0];
462 } else {
463 return 0xFF;
464 }
465 case GB_REGION_EXTERNAL_RAM:
466 case GB_REGION_EXTERNAL_RAM + 1:
467 if (memory->rtcAccess) {
468 return memory->rtcRegs[memory->activeRtcReg];
469 } else if (memory->sramAccess) {
470 if (segment < 0 && memory->sram) {
471 return memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)];
472 } else if ((size_t) segment * GB_SIZE_EXTERNAL_RAM < gb->sramSize) {
473 return memory->sram[(address & (GB_SIZE_EXTERNAL_RAM - 1)) + segment *GB_SIZE_EXTERNAL_RAM];
474 } else {
475 return 0xFF;
476 }
477 } else if (memory->mbcRead) {
478 return memory->mbcRead(memory, address);
479 } else if (memory->mbcType == GB_HuC3) {
480 return 0x01; // TODO: Is this supposed to be the current SRAM bank?
481 }
482 return 0xFF;
483 case GB_REGION_WORKING_RAM_BANK0:
484 case GB_REGION_WORKING_RAM_BANK0 + 2:
485 return memory->wram[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
486 case GB_REGION_WORKING_RAM_BANK1:
487 if (segment < 0) {
488 return memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
489 } else if (segment < 8) {
490 return memory->wram[(address & (GB_SIZE_WORKING_RAM_BANK0 - 1)) + segment *GB_SIZE_WORKING_RAM_BANK0];
491 } else {
492 return 0xFF;
493 }
494 default:
495 if (address < GB_BASE_OAM) {
496 return memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
497 }
498 if (address < GB_BASE_UNUSABLE) {
499 if (gb->video.mode < 2) {
500 return gb->video.oam.raw[address & 0xFF];
501 }
502 return 0xFF;
503 }
504 if (address < GB_BASE_IO) {
505 mLOG(GB_MEM, GAME_ERROR, "Attempt to read from unusable memory: %04X", address);
506 if (gb->video.mode < 2) {
507 switch (gb->model) {
508 case GB_MODEL_AGB:
509 return (address & 0xF0) | ((address >> 4) & 0xF);
510 case GB_MODEL_CGB:
511 // TODO: R/W behavior
512 return 0x00;
513 default:
514 return 0x00;
515 }
516 }
517 return 0xFF;
518 }
519 if (address < GB_BASE_HRAM) {
520 return GBIORead(gb, address & (GB_SIZE_IO - 1));
521 }
522 if (address < GB_BASE_IE) {
523 return memory->hram[address & GB_SIZE_HRAM];
524 }
525 return GBIORead(gb, GB_REG_IE);
526 }
527}
528
529void GBMemoryDMA(struct GB* gb, uint16_t base) {
530 if (base >= 0xE000) {
531 base &= 0xDFFF;
532 }
533 mTimingDeschedule(&gb->timing, &gb->memory.dmaEvent);
534 mTimingSchedule(&gb->timing, &gb->memory.dmaEvent, 8 * (2 - gb->doubleSpeed));
535 gb->memory.dmaSource = base;
536 gb->memory.dmaDest = 0;
537 gb->memory.dmaRemaining = 0xA0;
538}
539
540uint8_t GBMemoryWriteHDMA5(struct GB* gb, uint8_t value) {
541 gb->memory.hdmaSource = gb->memory.io[GB_REG_HDMA1] << 8;
542 gb->memory.hdmaSource |= gb->memory.io[GB_REG_HDMA2];
543 gb->memory.hdmaDest = gb->memory.io[GB_REG_HDMA3] << 8;
544 gb->memory.hdmaDest |= gb->memory.io[GB_REG_HDMA4];
545 gb->memory.hdmaSource &= 0xFFF0;
546 if (gb->memory.hdmaSource >= 0x8000 && gb->memory.hdmaSource < 0xA000) {
547 mLOG(GB_MEM, GAME_ERROR, "Invalid HDMA source: %04X", gb->memory.hdmaSource);
548 return value | 0x80;
549 }
550 gb->memory.hdmaDest &= 0x1FF0;
551 gb->memory.hdmaDest |= 0x8000;
552 bool wasHdma = gb->memory.isHdma;
553 gb->memory.isHdma = value & 0x80;
554 if ((!wasHdma && !gb->memory.isHdma) || (GBRegisterLCDCIsEnable(gb->memory.io[GB_REG_LCDC]) && gb->video.mode == 0)) {
555 if (gb->memory.isHdma) {
556 gb->memory.hdmaRemaining = 0x10;
557 } else {
558 gb->memory.hdmaRemaining = ((value & 0x7F) + 1) * 0x10;
559 }
560 gb->cpuBlocked = true;
561 mTimingSchedule(&gb->timing, &gb->memory.hdmaEvent, 0);
562 } else if (gb->memory.isHdma && !GBRegisterLCDCIsEnable(gb->memory.io[GB_REG_LCDC])) {
563 return 0x80 | ((value + 1) & 0x7F);
564 }
565 return value & 0x7F;
566}
567
568void _GBMemoryDMAService(struct mTiming* timing, void* context, uint32_t cyclesLate) {
569 struct GB* gb = context;
570 int dmaRemaining = gb->memory.dmaRemaining;
571 gb->memory.dmaRemaining = 0;
572 uint8_t b = GBLoad8(gb->cpu, gb->memory.dmaSource);
573 // TODO: Can DMA write OAM during modes 2-3?
574 gb->video.oam.raw[gb->memory.dmaDest] = b;
575 gb->video.renderer->writeOAM(gb->video.renderer, gb->memory.dmaDest);
576 ++gb->memory.dmaSource;
577 ++gb->memory.dmaDest;
578 gb->memory.dmaRemaining = dmaRemaining - 1;
579 if (gb->memory.dmaRemaining) {
580 mTimingSchedule(timing, &gb->memory.dmaEvent, 4 * (2 - gb->doubleSpeed) - cyclesLate);
581 }
582}
583
584void _GBMemoryHDMAService(struct mTiming* timing, void* context, uint32_t cyclesLate) {
585 struct GB* gb = context;
586 gb->cpuBlocked = true;
587 uint8_t b = gb->cpu->memory.load8(gb->cpu, gb->memory.hdmaSource);
588 gb->cpu->memory.store8(gb->cpu, gb->memory.hdmaDest, b);
589 ++gb->memory.hdmaSource;
590 ++gb->memory.hdmaDest;
591 --gb->memory.hdmaRemaining;
592 if (gb->memory.hdmaRemaining) {
593 mTimingDeschedule(timing, &gb->memory.hdmaEvent);
594 mTimingSchedule(timing, &gb->memory.hdmaEvent, 4 - cyclesLate);
595 } else {
596 gb->cpuBlocked = false;
597 gb->memory.io[GB_REG_HDMA1] = gb->memory.hdmaSource >> 8;
598 gb->memory.io[GB_REG_HDMA2] = gb->memory.hdmaSource;
599 gb->memory.io[GB_REG_HDMA3] = gb->memory.hdmaDest >> 8;
600 gb->memory.io[GB_REG_HDMA4] = gb->memory.hdmaDest;
601 if (gb->memory.isHdma) {
602 --gb->memory.io[GB_REG_HDMA5];
603 if (gb->memory.io[GB_REG_HDMA5] == 0xFF) {
604 gb->memory.isHdma = false;
605 }
606 } else {
607 gb->memory.io[GB_REG_HDMA5] = 0xFF;
608 }
609 }
610}
611
612void GBPatch8(struct SM83Core* cpu, uint16_t address, int8_t value, int8_t* old, int segment) {
613 struct GB* gb = (struct GB*) cpu->master;
614 struct GBMemory* memory = &gb->memory;
615 int8_t oldValue = -1;
616
617 switch (address >> 12) {
618 case GB_REGION_CART_BANK0:
619 case GB_REGION_CART_BANK0 + 1:
620 case GB_REGION_CART_BANK0 + 2:
621 case GB_REGION_CART_BANK0 + 3:
622 _pristineCow(gb);
623 oldValue = memory->romBase[address & (GB_SIZE_CART_BANK0 - 1)];
624 memory->romBase[address & (GB_SIZE_CART_BANK0 - 1)] = value;
625 break;
626 case GB_REGION_CART_BANK1:
627 case GB_REGION_CART_BANK1 + 1:
628 case GB_REGION_CART_BANK1 + 2:
629 case GB_REGION_CART_BANK1 + 3:
630 _pristineCow(gb);
631 if (segment < 0) {
632 oldValue = memory->romBank[address & (GB_SIZE_CART_BANK0 - 1)];
633 memory->romBank[address & (GB_SIZE_CART_BANK0 - 1)] = value;
634 } else if ((size_t) segment * GB_SIZE_CART_BANK0 < memory->romSize) {
635 oldValue = memory->rom[(address & (GB_SIZE_CART_BANK0 - 1)) + segment * GB_SIZE_CART_BANK0];
636 memory->rom[(address & (GB_SIZE_CART_BANK0 - 1)) + segment * GB_SIZE_CART_BANK0] = value;
637 } else {
638 return;
639 }
640 break;
641 case GB_REGION_VRAM:
642 case GB_REGION_VRAM + 1:
643 if (segment < 0) {
644 oldValue = gb->video.vramBank[address & (GB_SIZE_VRAM_BANK0 - 1)];
645 gb->video.vramBank[address & (GB_SIZE_VRAM_BANK0 - 1)] = value;
646 gb->video.renderer->writeVRAM(gb->video.renderer, (address & (GB_SIZE_VRAM_BANK0 - 1)) + GB_SIZE_VRAM_BANK0 * gb->video.vramCurrentBank);
647 } else if (segment < 2) {
648 oldValue = gb->video.vram[(address & (GB_SIZE_VRAM_BANK0 - 1)) + segment * GB_SIZE_VRAM_BANK0];
649 gb->video.vramBank[(address & (GB_SIZE_VRAM_BANK0 - 1)) + segment * GB_SIZE_VRAM_BANK0] = value;
650 gb->video.renderer->writeVRAM(gb->video.renderer, (address & (GB_SIZE_VRAM_BANK0 - 1)) + segment * GB_SIZE_VRAM_BANK0);
651 } else {
652 return;
653 }
654 break;
655 case GB_REGION_EXTERNAL_RAM:
656 case GB_REGION_EXTERNAL_RAM + 1:
657 if (memory->rtcAccess) {
658 memory->rtcRegs[memory->activeRtcReg] = value;
659 } else if (memory->sramAccess && memory->sram && memory->mbcType != GB_MBC2) {
660 // TODO: Remove sramAccess check?
661 memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)] = value;
662 } else {
663 memory->mbcWrite(gb, address, value);
664 }
665 gb->sramDirty |= GB_SRAM_DIRT_NEW;
666 return;
667 case GB_REGION_WORKING_RAM_BANK0:
668 case GB_REGION_WORKING_RAM_BANK0 + 2:
669 oldValue = memory->wram[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
670 memory->wram[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)] = value;
671 break;
672 case GB_REGION_WORKING_RAM_BANK1:
673 if (segment < 0) {
674 oldValue = memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
675 memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)] = value;
676 } else if (segment < 8) {
677 oldValue = memory->wram[(address & (GB_SIZE_WORKING_RAM_BANK0 - 1)) + segment * GB_SIZE_WORKING_RAM_BANK0];
678 memory->wram[(address & (GB_SIZE_WORKING_RAM_BANK0 - 1)) + segment * GB_SIZE_WORKING_RAM_BANK0] = value;
679 } else {
680 return;
681 }
682 break;
683 default:
684 if (address < GB_BASE_OAM) {
685 oldValue = memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)];
686 memory->wramBank[address & (GB_SIZE_WORKING_RAM_BANK0 - 1)] = value;
687 } else if (address < GB_BASE_UNUSABLE) {
688 oldValue = gb->video.oam.raw[address & 0xFF];
689 gb->video.oam.raw[address & 0xFF] = value;
690 gb->video.renderer->writeOAM(gb->video.renderer, address & 0xFF);
691 } else if (address < GB_BASE_HRAM) {
692 mLOG(GB_MEM, STUB, "Unimplemented memory Patch8: 0x%08X", address);
693 return;
694 } else if (address < GB_BASE_IE) {
695 oldValue = memory->hram[address & GB_SIZE_HRAM];
696 memory->hram[address & GB_SIZE_HRAM] = value;
697 } else {
698 mLOG(GB_MEM, STUB, "Unimplemented memory Patch8: 0x%08X", address);
699 return;
700 }
701 }
702 if (old) {
703 *old = oldValue;
704 }
705}
706
707void GBMemorySerialize(const struct GB* gb, struct GBSerializedState* state) {
708 const struct GBMemory* memory = &gb->memory;
709 memcpy(state->wram, memory->wram, GB_SIZE_WORKING_RAM);
710 memcpy(state->hram, memory->hram, GB_SIZE_HRAM);
711 STORE_16LE(memory->currentBank, 0, &state->memory.currentBank);
712 state->memory.wramCurrentBank = memory->wramCurrentBank;
713 state->memory.sramCurrentBank = memory->sramCurrentBank;
714
715 STORE_16LE(memory->dmaSource, 0, &state->memory.dmaSource);
716 STORE_16LE(memory->dmaDest, 0, &state->memory.dmaDest);
717
718 STORE_16LE(memory->hdmaSource, 0, &state->memory.hdmaSource);
719 STORE_16LE(memory->hdmaDest, 0, &state->memory.hdmaDest);
720
721 STORE_16LE(memory->hdmaRemaining, 0, &state->memory.hdmaRemaining);
722 state->memory.dmaRemaining = memory->dmaRemaining;
723 memcpy(state->memory.rtcRegs, memory->rtcRegs, sizeof(state->memory.rtcRegs));
724
725 STORE_32LE(memory->dmaEvent.when - mTimingCurrentTime(&gb->timing), 0, &state->memory.dmaNext);
726 STORE_32LE(memory->hdmaEvent.when - mTimingCurrentTime(&gb->timing), 0, &state->memory.hdmaNext);
727
728 GBSerializedMemoryFlags flags = 0;
729 flags = GBSerializedMemoryFlagsSetSramAccess(flags, memory->sramAccess);
730 flags = GBSerializedMemoryFlagsSetRtcAccess(flags, memory->rtcAccess);
731 flags = GBSerializedMemoryFlagsSetRtcLatched(flags, memory->rtcLatched);
732 flags = GBSerializedMemoryFlagsSetIme(flags, memory->ime);
733 flags = GBSerializedMemoryFlagsSetIsHdma(flags, memory->isHdma);
734 flags = GBSerializedMemoryFlagsSetActiveRtcReg(flags, memory->activeRtcReg);
735 STORE_16LE(flags, 0, &state->memory.flags);
736
737 switch (memory->mbcType) {
738 case GB_MBC1:
739 state->memory.mbc1.mode = memory->mbcState.mbc1.mode;
740 state->memory.mbc1.multicartStride = memory->mbcState.mbc1.multicartStride;
741 state->memory.mbc1.bankLo = memory->mbcState.mbc1.bankLo;
742 state->memory.mbc1.bankHi = memory->mbcState.mbc1.bankHi;
743 break;
744 case GB_MBC3_RTC:
745 STORE_64LE(gb->memory.rtcLastLatch, 0, &state->memory.rtc.lastLatch);
746 break;
747 case GB_MBC7:
748 state->memory.mbc7.state = memory->mbcState.mbc7.state;
749 state->memory.mbc7.eeprom = memory->mbcState.mbc7.eeprom;
750 state->memory.mbc7.address = memory->mbcState.mbc7.address;
751 state->memory.mbc7.access = memory->mbcState.mbc7.access;
752 state->memory.mbc7.latch = memory->mbcState.mbc7.latch;
753 state->memory.mbc7.srBits = memory->mbcState.mbc7.srBits;
754 STORE_16LE(memory->mbcState.mbc7.sr, 0, &state->memory.mbc7.sr);
755 STORE_32LE(memory->mbcState.mbc7.writable, 0, &state->memory.mbc7.writable);
756 break;
757 case GB_MMM01:
758 state->memory.mmm01.locked = memory->mbcState.mmm01.locked;
759 state->memory.mmm01.bank0 = memory->mbcState.mmm01.currentBank0;
760 break;
761 case GB_UNL_BBD:
762 case GB_UNL_HITEK:
763 state->memory.bbd.dataSwapMode = memory->mbcState.bbd.dataSwapMode;
764 state->memory.bbd.bankSwapMode = memory->mbcState.bbd.bankSwapMode;
765 break;
766 default:
767 break;
768 }
769}
770
771void GBMemoryDeserialize(struct GB* gb, const struct GBSerializedState* state) {
772 struct GBMemory* memory = &gb->memory;
773 memcpy(memory->wram, state->wram, GB_SIZE_WORKING_RAM);
774 memcpy(memory->hram, state->hram, GB_SIZE_HRAM);
775 LOAD_16LE(memory->currentBank, 0, &state->memory.currentBank);
776 memory->wramCurrentBank = state->memory.wramCurrentBank;
777 memory->sramCurrentBank = state->memory.sramCurrentBank;
778
779 GBMBCSwitchBank(gb, memory->currentBank);
780 GBMemorySwitchWramBank(memory, memory->wramCurrentBank);
781 GBMBCSwitchSramBank(gb, memory->sramCurrentBank);
782
783 LOAD_16LE(memory->dmaSource, 0, &state->memory.dmaSource);
784 LOAD_16LE(memory->dmaDest, 0, &state->memory.dmaDest);
785
786 LOAD_16LE(memory->hdmaSource, 0, &state->memory.hdmaSource);
787 LOAD_16LE(memory->hdmaDest, 0, &state->memory.hdmaDest);
788
789 LOAD_16LE(memory->hdmaRemaining, 0, &state->memory.hdmaRemaining);
790 memory->dmaRemaining = state->memory.dmaRemaining;
791 memcpy(memory->rtcRegs, state->memory.rtcRegs, sizeof(state->memory.rtcRegs));
792
793 uint32_t when;
794 LOAD_32LE(when, 0, &state->memory.dmaNext);
795 if (memory->dmaRemaining) {
796 mTimingSchedule(&gb->timing, &memory->dmaEvent, when);
797 } else {
798 memory->dmaEvent.when = when + mTimingCurrentTime(&gb->timing);
799 }
800 LOAD_32LE(when, 0, &state->memory.hdmaNext);
801 if (memory->hdmaRemaining) {
802 mTimingSchedule(&gb->timing, &memory->hdmaEvent, when);
803 } else {
804 memory->hdmaEvent.when = when + mTimingCurrentTime(&gb->timing);
805 }
806
807 GBSerializedMemoryFlags flags;
808 LOAD_16LE(flags, 0, &state->memory.flags);
809 memory->sramAccess = GBSerializedMemoryFlagsGetSramAccess(flags);
810 memory->rtcAccess = GBSerializedMemoryFlagsGetRtcAccess(flags);
811 memory->rtcLatched = GBSerializedMemoryFlagsGetRtcLatched(flags);
812 memory->ime = GBSerializedMemoryFlagsGetIme(flags);
813 memory->isHdma = GBSerializedMemoryFlagsGetIsHdma(flags);
814 memory->activeRtcReg = GBSerializedMemoryFlagsGetActiveRtcReg(flags);
815
816 switch (memory->mbcType) {
817 case GB_MBC1:
818 memory->mbcState.mbc1.mode = state->memory.mbc1.mode;
819 memory->mbcState.mbc1.multicartStride = state->memory.mbc1.multicartStride;
820 memory->mbcState.mbc1.bankLo = state->memory.mbc1.bankLo;
821 memory->mbcState.mbc1.bankHi = state->memory.mbc1.bankHi;
822 if (!(memory->mbcState.mbc1.bankLo || memory->mbcState.mbc1.bankHi)) {
823 // Backwards compat
824 memory->mbcState.mbc1.bankLo = memory->currentBank & ((1 << memory->mbcState.mbc1.multicartStride) - 1);
825 memory->mbcState.mbc1.bankHi = memory->currentBank >> memory->mbcState.mbc1.multicartStride;
826 }
827 if (memory->mbcState.mbc1.mode) {
828 GBMBCSwitchBank0(gb, memory->mbcState.mbc1.bankHi);
829 }
830 break;
831 case GB_MBC3_RTC:
832 LOAD_64LE(gb->memory.rtcLastLatch, 0, &state->memory.rtc.lastLatch);
833 break;
834 case GB_MBC7:
835 memory->mbcState.mbc7.state = state->memory.mbc7.state;
836 memory->mbcState.mbc7.eeprom = state->memory.mbc7.eeprom;
837 memory->mbcState.mbc7.address = state->memory.mbc7.address & 0x7F;
838 memory->mbcState.mbc7.access = state->memory.mbc7.access;
839 memory->mbcState.mbc7.latch = state->memory.mbc7.latch;
840 memory->mbcState.mbc7.srBits = state->memory.mbc7.srBits;
841 LOAD_16LE(memory->mbcState.mbc7.sr, 0, &state->memory.mbc7.sr);
842 LOAD_32LE(memory->mbcState.mbc7.writable, 0, &state->memory.mbc7.writable);
843 break;
844 case GB_MMM01:
845 memory->mbcState.mmm01.locked = state->memory.mmm01.locked;
846 memory->mbcState.mmm01.currentBank0 = state->memory.mmm01.bank0;
847 if (memory->mbcState.mmm01.locked) {
848 GBMBCSwitchBank0(gb, memory->mbcState.mmm01.currentBank0);
849 } else {
850 GBMBCSwitchBank0(gb, gb->memory.romSize / GB_SIZE_CART_BANK0 - 2);
851 }
852 break;
853 case GB_UNL_BBD:
854 case GB_UNL_HITEK:
855 memory->mbcState.bbd.dataSwapMode = state->memory.bbd.dataSwapMode & 0x7;
856 memory->mbcState.bbd.bankSwapMode = state->memory.bbd.bankSwapMode & 0x7;
857 break;
858 default:
859 break;
860 }
861}
862
863void _pristineCow(struct GB* gb) {
864 if (!gb->isPristine) {
865 return;
866 }
867 void* newRom = anonymousMemoryMap(GB_SIZE_CART_MAX);
868 memcpy(newRom, gb->memory.rom, gb->memory.romSize);
869 memset(((uint8_t*) newRom) + gb->memory.romSize, 0xFF, GB_SIZE_CART_MAX - gb->memory.romSize);
870 if (gb->memory.rom == gb->memory.romBase) {
871 gb->memory.romBase = newRom;
872 }
873 gb->memory.rom = newRom;
874 GBMBCSwitchBank(gb, gb->memory.currentBank);
875 gb->isPristine = false;
876}