all repos — mgba @ 0ddac5e9614cefe166bee5920ad4455b78d92a35

mGBA Game Boy Advance Emulator

src/gba/io.c (view raw)

  1/* Copyright (c) 2013-2015 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 "io.h"
  7
  8#include "gba/rr/rr.h"
  9#include "gba/serialize.h"
 10#include "gba/sio.h"
 11#include "gba/video.h"
 12
 13mLOG_DEFINE_CATEGORY(GBA_IO, "GBA I/O");
 14
 15const char* GBAIORegisterNames[] = {
 16	// Video
 17	"DISPCNT",
 18	0,
 19	"DISPSTAT",
 20	"VCOUNT",
 21	"BG0CNT",
 22	"BG1CNT",
 23	"BG2CNT",
 24	"BG3CNT",
 25	"BG0HOFS",
 26	"BG0VOFS",
 27	"BG1HOFS",
 28	"BG1VOFS",
 29	"BG2HOFS",
 30	"BG2VOFS",
 31	"BG3HOFS",
 32	"BG3VOFS",
 33	"BG2PA",
 34	"BG2PB",
 35	"BG2PC",
 36	"BG2PD",
 37	"BG2X_LO",
 38	"BG2X_HI",
 39	"BG2Y_LO",
 40	"BG2Y_HI",
 41	"BG3PA",
 42	"BG3PB",
 43	"BG3PC",
 44	"BG3PD",
 45	"BG3X_LO",
 46	"BG3X_HI",
 47	"BG3Y_LO",
 48	"BG3Y_HI",
 49	"WIN0H",
 50	"WIN1H",
 51	"WIN0V",
 52	"WIN1V",
 53	"WININ",
 54	"WINOUT",
 55	"MOSAIC",
 56	0,
 57	"BLDCNT",
 58	"BLDALPHA",
 59	"BLDY",
 60	0,
 61	0,
 62	0,
 63	0,
 64	0,
 65
 66	// Sound
 67	"SOUND1CNT_LO",
 68	"SOUND1CNT_HI",
 69	"SOUND1CNT_X",
 70	0,
 71	"SOUND2CNT_LO",
 72	0,
 73	"SOUND2CNT_HI",
 74	0,
 75	"SOUND3CNT_LO",
 76	"SOUND3CNT_HI",
 77	"SOUND3CNT_X",
 78	0,
 79	"SOUND4CNT_LO",
 80	0,
 81	"SOUND4CNT_HI",
 82	0,
 83	"SOUNDCNT_LO",
 84	"SOUNDCNT_HI",
 85	"SOUNDCNT_X",
 86	0,
 87	"SOUNDBIAS",
 88	0,
 89	0,
 90	0,
 91	"WAVE_RAM0_LO",
 92	"WAVE_RAM0_HI",
 93	"WAVE_RAM1_LO",
 94	"WAVE_RAM1_HI",
 95	"WAVE_RAM2_LO",
 96	"WAVE_RAM2_HI",
 97	"WAVE_RAM3_LO",
 98	"WAVE_RAM3_HI",
 99	"FIFO_A_LO",
100	"FIFO_A_HI",
101	"FIFO_B_LO",
102	"FIFO_B_HI",
103	0,
104	0,
105	0,
106	0,
107
108	// DMA
109	"DMA0SAD_LO",
110	"DMA0SAD_HI",
111	"DMA0DAD_LO",
112	"DMA0DAD_HI",
113	"DMA0CNT_LO",
114	"DMA0CNT_HI",
115	"DMA1SAD_LO",
116	"DMA1SAD_HI",
117	"DMA1DAD_LO",
118	"DMA1DAD_HI",
119	"DMA1CNT_LO",
120	"DMA1CNT_HI",
121	"DMA2SAD_LO",
122	"DMA2SAD_HI",
123	"DMA2DAD_LO",
124	"DMA2DAD_HI",
125	"DMA2CNT_LO",
126	"DMA2CNT_HI",
127	"DMA3SAD_LO",
128	"DMA3SAD_HI",
129	"DMA3DAD_LO",
130	"DMA3DAD_HI",
131	"DMA3CNT_LO",
132	"DMA3CNT_HI",
133
134	0, 0, 0, 0, 0, 0, 0, 0,
135	0, 0, 0, 0, 0, 0, 0, 0,
136
137	// Timers
138	"TM0CNT_LO",
139	"TM0CNT_HI",
140	"TM1CNT_LO",
141	"TM1CNT_HI",
142	"TM2CNT_LO",
143	"TM2CNT_HI",
144	"TM3CNT_LO",
145	"TM3CNT_HI",
146
147	0, 0, 0, 0, 0, 0, 0, 0,
148
149	// SIO
150	"SIOMULTI0",
151	"SIOMULTI1",
152	"SIOMULTI2",
153	"SIOMULTI3",
154	"SIOCNT",
155	"SIOMLT_SEND",
156	0,
157	0,
158	"KEYINPUT",
159	"KEYCNT",
160	"RCNT",
161	0,
162	0,
163	0,
164	0,
165	0,
166	"JOYCNT",
167	0,
168	0,
169	0,
170	0,
171	0,
172	0,
173	0,
174	"JOY_RECV_LO",
175	"JOY_RECV_HI",
176	"JOY_TRANS_LO",
177	"JOY_TRANS_HI",
178	"JOYSTAT",
179	0,
180	0,
181	0,
182
183	0, 0, 0, 0, 0, 0, 0, 0,
184	0, 0, 0, 0, 0, 0, 0, 0,
185	0, 0, 0, 0, 0, 0, 0, 0,
186	0, 0, 0, 0, 0, 0, 0, 0,
187	0, 0, 0, 0, 0, 0, 0, 0,
188	0, 0, 0, 0, 0, 0, 0, 0,
189	0, 0, 0, 0, 0, 0, 0, 0,
190	0, 0, 0, 0, 0, 0, 0, 0,
191	0, 0, 0, 0, 0, 0, 0, 0,
192	0, 0, 0, 0, 0, 0, 0, 0,
193
194	// Interrupts, etc
195	"IE",
196	"IF",
197	"WAITCNT",
198	0,
199	"IME"
200};
201
202static const int _isValidRegister[REG_MAX >> 1] = {
203	// Video
204	1, 0, 1, 1, 1, 1, 1, 1,
205	1, 1, 1, 1, 1, 1, 1, 1,
206	1, 1, 1, 1, 1, 1, 1, 1,
207	1, 1, 1, 1, 1, 1, 1, 1,
208	1, 1, 1, 1, 1, 1, 1, 0,
209	1, 1, 1, 0, 0, 0, 0, 0,
210	// Audio
211	1, 1, 1, 0, 1, 0, 1, 0,
212	1, 1, 1, 0, 1, 0, 1, 0,
213	1, 1, 1, 0, 1, 0, 0, 0,
214	1, 1, 1, 1, 1, 1, 1, 1,
215	1, 1, 1, 1, 0, 0, 0, 0,
216	// DMA
217	1, 1, 1, 1, 1, 1, 1, 1,
218	1, 1, 1, 1, 1, 1, 1, 1,
219	1, 1, 1, 1, 1, 1, 1, 1,
220	0, 0, 0, 0, 0, 0, 0, 0,
221	0, 0, 0, 0, 0, 0, 0, 0,
222	// Timers
223	1, 1, 1, 1, 1, 1, 1, 1,
224	0, 0, 0, 0, 0, 0, 0, 0,
225	// SIO
226	1, 1, 1, 1, 1, 0, 0, 0,
227	1, 1, 1, 0, 0, 0, 0, 0,
228	1, 0, 0, 0, 0, 0, 0, 0,
229	1, 0, 1, 0, 1, 0, 0, 0,
230	0, 0, 0, 0, 0, 0, 0, 0,
231	0, 0, 0, 0, 0, 0, 0, 0,
232	0, 0, 0, 0, 0, 0, 0, 0,
233	0, 0, 0, 0, 0, 0, 0, 0,
234	0, 0, 0, 0, 0, 0, 0, 0,
235	0, 0, 0, 0, 0, 0, 0, 0,
236	0, 0, 0, 0, 0, 0, 0, 0,
237	0, 0, 0, 0, 0, 0, 0, 0,
238	0, 0, 0, 0, 0, 0, 0, 0,
239	0, 0, 0, 0, 0, 0, 0, 0,
240	// Interrupts
241	1, 1, 1, 0, 1
242};
243
244static const int _isRSpecialRegister[REG_MAX >> 1] = {
245	// Video
246	0, 0, 1, 1, 0, 0, 0, 0,
247	1, 1, 1, 1, 1, 1, 1, 1,
248	1, 1, 1, 1, 1, 1, 1, 1,
249	1, 1, 1, 1, 1, 1, 1, 1,
250	1, 1, 1, 1, 1, 1, 1, 1,
251	1, 1, 1, 1, 1, 1, 1, 1,
252	// Audio
253	0, 0, 0, 0, 0, 0, 0, 0,
254	0, 0, 0, 0, 0, 0, 0, 0,
255	0, 0, 0, 0, 1, 0, 0, 0,
256	1, 1, 1, 1, 1, 1, 1, 1,
257	1, 1, 1, 1, 0, 0, 0, 0,
258	// DMA
259	1, 1, 1, 1, 1, 1, 1, 1,
260	1, 1, 1, 1, 1, 1, 1, 1,
261	1, 1, 1, 1, 1, 1, 1, 1,
262	0, 0, 0, 0, 0, 0, 0, 0,
263	0, 0, 0, 0, 0, 0, 0, 0,
264	// Timers
265	1, 1, 1, 1, 1, 1, 1, 1,
266	0, 0, 0, 0, 0, 0, 0, 0,
267	// SIO
268	1, 1, 1, 1, 1, 0, 0, 0,
269	1, 1, 1, 0, 0, 0, 0, 0,
270	1, 0, 0, 0, 0, 0, 0, 0,
271	1, 0, 1, 0, 1, 0, 0, 0,
272	0, 0, 0, 0, 0, 0, 0, 0,
273	0, 0, 0, 0, 0, 0, 0, 0,
274	0, 0, 0, 0, 0, 0, 0, 0,
275	0, 0, 0, 0, 0, 0, 0, 0,
276	0, 0, 0, 0, 0, 0, 0, 0,
277	0, 0, 0, 0, 0, 0, 0, 0,
278	0, 0, 0, 0, 0, 0, 0, 0,
279	0, 0, 0, 0, 0, 0, 0, 0,
280	0, 0, 0, 0, 0, 0, 0, 0,
281	0, 0, 0, 0, 0, 0, 0, 0,
282	// Interrupts
283};
284
285static const int _isWSpecialRegister[REG_MAX >> 1] = {
286	// Video
287	0, 0, 1, 1, 0, 0, 0, 0,
288	0, 0, 0, 0, 0, 0, 0, 0,
289	0, 0, 0, 0, 0, 0, 0, 0,
290	0, 0, 0, 0, 0, 0, 0, 0,
291	0, 0, 0, 0, 0, 0, 0, 0,
292	0, 0, 0, 0, 0, 0, 0, 0,
293	// Audio
294	0, 0, 0, 0, 0, 0, 0, 0,
295	0, 0, 0, 0, 0, 0, 0, 0,
296	0, 0, 1, 0, 0, 0, 0, 0,
297	1, 1, 1, 1, 1, 1, 1, 1,
298	1, 1, 1, 1, 0, 0, 0, 0,
299	// DMA
300	0, 0, 0, 0, 0, 1, 0, 0,
301	0, 0, 0, 1, 0, 0, 0, 0,
302	0, 1, 0, 0, 0, 0, 0, 1,
303	0, 0, 0, 0, 0, 0, 0, 0,
304	0, 0, 0, 0, 0, 0, 0, 0,
305	// Timers
306	1, 1, 1, 1, 1, 1, 1, 1,
307	0, 0, 0, 0, 0, 0, 0, 0,
308	// SIO
309	1, 1, 1, 1, 1, 0, 0, 0,
310	1, 1, 1, 0, 0, 0, 0, 0,
311	1, 0, 0, 0, 0, 0, 0, 0,
312	1, 0, 1, 0, 1, 0, 0, 0,
313	0, 0, 0, 0, 0, 0, 0, 0,
314	0, 0, 0, 0, 0, 0, 0, 0,
315	0, 0, 0, 0, 0, 0, 0, 0,
316	0, 0, 0, 0, 0, 0, 0, 0,
317	0, 0, 0, 0, 0, 0, 0, 0,
318	0, 0, 0, 0, 0, 0, 0, 0,
319	0, 0, 0, 0, 0, 0, 0, 0,
320	0, 0, 0, 0, 0, 0, 0, 0,
321	0, 0, 0, 0, 0, 0, 0, 0,
322	0, 0, 0, 0, 0, 0, 0, 0,
323	// Interrupts
324	1, 1, 0, 0, 1
325};
326
327void GBAIOInit(struct GBA* gba) {
328	gba->memory.io[REG_DISPCNT >> 1] = 0x0080;
329	gba->memory.io[REG_RCNT >> 1] = RCNT_INITIAL;
330	gba->memory.io[REG_KEYINPUT >> 1] = 0x3FF;
331	gba->memory.io[REG_SOUNDBIAS >> 1] = 0x200;
332	gba->memory.io[REG_BG2PA >> 1] = 0x100;
333	gba->memory.io[REG_BG2PD >> 1] = 0x100;
334	gba->memory.io[REG_BG3PA >> 1] = 0x100;
335	gba->memory.io[REG_BG3PD >> 1] = 0x100;
336}
337
338void GBAIOWrite(struct GBA* gba, uint32_t address, uint16_t value) {
339	if (address < REG_SOUND1CNT_LO && address != REG_DISPSTAT) {
340		value = gba->video.renderer->writeVideoRegister(gba->video.renderer, address, value);
341	} else {
342		switch (address) {
343		// Video
344		case REG_DISPSTAT:
345			value &= 0xFFF8;
346			GBAVideoWriteDISPSTAT(&gba->video, value);
347			return;
348
349		// Audio
350		case REG_SOUND1CNT_LO:
351			GBAAudioWriteSOUND1CNT_LO(&gba->audio, value);
352			value &= 0x007F;
353			break;
354		case REG_SOUND1CNT_HI:
355			GBAAudioWriteSOUND1CNT_HI(&gba->audio, value);
356			break;
357		case REG_SOUND1CNT_X:
358			GBAAudioWriteSOUND1CNT_X(&gba->audio, value);
359			value &= 0x47FF;
360			break;
361		case REG_SOUND2CNT_LO:
362			GBAAudioWriteSOUND2CNT_LO(&gba->audio, value);
363			break;
364		case REG_SOUND2CNT_HI:
365			GBAAudioWriteSOUND2CNT_HI(&gba->audio, value);
366			value &= 0x47FF;
367			break;
368		case REG_SOUND3CNT_LO:
369			GBAAudioWriteSOUND3CNT_LO(&gba->audio, value);
370			value &= 0x00E0;
371			break;
372		case REG_SOUND3CNT_HI:
373			GBAAudioWriteSOUND3CNT_HI(&gba->audio, value);
374			value &= 0xE03F;
375			break;
376		case REG_SOUND3CNT_X:
377			GBAAudioWriteSOUND3CNT_X(&gba->audio, value);
378			// TODO: The low bits need to not be readable, but still 8-bit writable
379			value &= 0x47FF;
380			break;
381		case REG_SOUND4CNT_LO:
382			GBAAudioWriteSOUND4CNT_LO(&gba->audio, value);
383			value &= 0xFF3F;
384			break;
385		case REG_SOUND4CNT_HI:
386			GBAAudioWriteSOUND4CNT_HI(&gba->audio, value);
387			value &= 0x40FF;
388			break;
389		case REG_SOUNDCNT_LO:
390			GBAAudioWriteSOUNDCNT_LO(&gba->audio, value);
391			value &= 0xFF77;
392			break;
393		case REG_SOUNDCNT_HI:
394			GBAAudioWriteSOUNDCNT_HI(&gba->audio, value);
395			value &= 0x770F;
396			break;
397		case REG_SOUNDCNT_X:
398			GBAAudioWriteSOUNDCNT_X(&gba->audio, value);
399			value &= 0x0080;
400			value |= gba->memory.io[REG_SOUNDCNT_X >> 1] & 0xF;
401			break;
402		case REG_SOUNDBIAS:
403			GBAAudioWriteSOUNDBIAS(&gba->audio, value);
404			break;
405
406		case REG_WAVE_RAM0_LO:
407		case REG_WAVE_RAM1_LO:
408		case REG_WAVE_RAM2_LO:
409		case REG_WAVE_RAM3_LO:
410			GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
411			break;
412
413		case REG_WAVE_RAM0_HI:
414		case REG_WAVE_RAM1_HI:
415		case REG_WAVE_RAM2_HI:
416		case REG_WAVE_RAM3_HI:
417			GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
418			break;
419
420		case REG_FIFO_A_LO:
421		case REG_FIFO_B_LO:
422			GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
423			break;
424
425		case REG_FIFO_A_HI:
426		case REG_FIFO_B_HI:
427			GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
428			break;
429
430		// DMA
431		case REG_DMA0SAD_LO:
432		case REG_DMA0DAD_LO:
433		case REG_DMA1SAD_LO:
434		case REG_DMA1DAD_LO:
435		case REG_DMA2SAD_LO:
436		case REG_DMA2DAD_LO:
437		case REG_DMA3SAD_LO:
438		case REG_DMA3DAD_LO:
439			GBAIOWrite32(gba, address, (gba->memory.io[(address >> 1) + 1] << 16) | value);
440			break;
441
442		case REG_DMA0SAD_HI:
443		case REG_DMA0DAD_HI:
444		case REG_DMA1SAD_HI:
445		case REG_DMA1DAD_HI:
446		case REG_DMA2SAD_HI:
447		case REG_DMA2DAD_HI:
448		case REG_DMA3SAD_HI:
449		case REG_DMA3DAD_HI:
450			GBAIOWrite32(gba, address - 2, gba->memory.io[(address >> 1) - 1] | (value << 16));
451			break;
452
453		case REG_DMA0CNT_LO:
454			GBAMemoryWriteDMACNT_LO(gba, 0, value);
455			break;
456		case REG_DMA0CNT_HI:
457			value = GBAMemoryWriteDMACNT_HI(gba, 0, value);
458			break;
459		case REG_DMA1CNT_LO:
460			GBAMemoryWriteDMACNT_LO(gba, 1, value);
461			break;
462		case REG_DMA1CNT_HI:
463			value = GBAMemoryWriteDMACNT_HI(gba, 1, value);
464			break;
465		case REG_DMA2CNT_LO:
466			GBAMemoryWriteDMACNT_LO(gba, 2, value);
467			break;
468		case REG_DMA2CNT_HI:
469			value = GBAMemoryWriteDMACNT_HI(gba, 2, value);
470			break;
471		case REG_DMA3CNT_LO:
472			GBAMemoryWriteDMACNT_LO(gba, 3, value);
473			break;
474		case REG_DMA3CNT_HI:
475			value = GBAMemoryWriteDMACNT_HI(gba, 3, value);
476			break;
477
478		// Timers
479		case REG_TM0CNT_LO:
480			GBATimerWriteTMCNT_LO(gba, 0, value);
481			return;
482		case REG_TM1CNT_LO:
483			GBATimerWriteTMCNT_LO(gba, 1, value);
484			return;
485		case REG_TM2CNT_LO:
486			GBATimerWriteTMCNT_LO(gba, 2, value);
487			return;
488		case REG_TM3CNT_LO:
489			GBATimerWriteTMCNT_LO(gba, 3, value);
490			return;
491
492		case REG_TM0CNT_HI:
493			value &= 0x00C7;
494			GBATimerWriteTMCNT_HI(gba, 0, value);
495			break;
496		case REG_TM1CNT_HI:
497			value &= 0x00C7;
498			GBATimerWriteTMCNT_HI(gba, 1, value);
499			break;
500		case REG_TM2CNT_HI:
501			value &= 0x00C7;
502			GBATimerWriteTMCNT_HI(gba, 2, value);
503			break;
504		case REG_TM3CNT_HI:
505			value &= 0x00C7;
506			GBATimerWriteTMCNT_HI(gba, 3, value);
507			break;
508
509		// SIO
510		case REG_SIOCNT:
511			GBASIOWriteSIOCNT(&gba->sio, value);
512			break;
513		case REG_RCNT:
514			value &= 0xC1FF;
515			GBASIOWriteRCNT(&gba->sio, value);
516			break;
517		case REG_SIOMLT_SEND:
518			GBASIOWriteSIOMLT_SEND(&gba->sio, value);
519			break;
520
521		// Interrupts and misc
522		case REG_WAITCNT:
523			GBAAdjustWaitstates(gba, value);
524			break;
525		case REG_IE:
526			GBAWriteIE(gba, value);
527			break;
528		case REG_IF:
529			value = gba->memory.io[REG_IF >> 1] & ~value;
530			break;
531		case REG_IME:
532			GBAWriteIME(gba, value);
533			break;
534		case REG_MAX:
535			// Some bad interrupt libraries will write to this
536			break;
537		default:
538			mLOG(GBA_IO, STUB, "Stub I/O register write: %03X", address);
539			if (address >= REG_MAX) {
540				mLOG(GBA_IO, GAME_ERROR, "Write to unused I/O register: %03X", address);
541				return;
542			}
543			break;
544		}
545	}
546	gba->memory.io[address >> 1] = value;
547}
548
549void GBAIOWrite8(struct GBA* gba, uint32_t address, uint8_t value) {
550	if (address == REG_HALTCNT) {
551		value &= 0x80;
552		if (!value) {
553			GBAHalt(gba);
554		} else {
555			GBAStop(gba);
556		}
557		return;
558	}
559	uint16_t value16 = value << (8 * (address & 1));
560	value16 |= (gba->memory.io[(address & (SIZE_IO - 1)) >> 1]) & ~(0xFF << (8 * (address & 1)));
561	GBAIOWrite(gba, address & 0xFFFFFFFE, value16);
562}
563
564void GBAIOWrite32(struct GBA* gba, uint32_t address, uint32_t value) {
565	switch (address) {
566	case REG_WAVE_RAM0_LO:
567		GBAAudioWriteWaveRAM(&gba->audio, 0, value);
568		break;
569	case REG_WAVE_RAM1_LO:
570		GBAAudioWriteWaveRAM(&gba->audio, 1, value);
571		break;
572	case REG_WAVE_RAM2_LO:
573		GBAAudioWriteWaveRAM(&gba->audio, 2, value);
574		break;
575	case REG_WAVE_RAM3_LO:
576		GBAAudioWriteWaveRAM(&gba->audio, 3, value);
577		break;
578	case REG_FIFO_A_LO:
579	case REG_FIFO_B_LO:
580		GBAAudioWriteFIFO(&gba->audio, address, value);
581		break;
582	case REG_DMA0SAD_LO:
583		value = GBAMemoryWriteDMASAD(gba, 0, value);
584		break;
585	case REG_DMA0DAD_LO:
586		value = GBAMemoryWriteDMADAD(gba, 0, value);
587		break;
588	case REG_DMA1SAD_LO:
589		value = GBAMemoryWriteDMASAD(gba, 1, value);
590		break;
591	case REG_DMA1DAD_LO:
592		value = GBAMemoryWriteDMADAD(gba, 1, value);
593		break;
594	case REG_DMA2SAD_LO:
595		value = GBAMemoryWriteDMASAD(gba, 2, value);
596		break;
597	case REG_DMA2DAD_LO:
598		value = GBAMemoryWriteDMADAD(gba, 2, value);
599		break;
600	case REG_DMA3SAD_LO:
601		value = GBAMemoryWriteDMASAD(gba, 3, value);
602		break;
603	case REG_DMA3DAD_LO:
604		value = GBAMemoryWriteDMADAD(gba, 3, value);
605		break;
606	default:
607		GBAIOWrite(gba, address, value & 0xFFFF);
608		GBAIOWrite(gba, address | 2, value >> 16);
609		return;
610	}
611	gba->memory.io[address >> 1] = value;
612	gba->memory.io[(address >> 1) + 1] = value >> 16;
613}
614
615bool GBAIOIsReadConstant(uint32_t address) {
616	switch (address) {
617	default:
618		return false;
619	case REG_BG0CNT:
620	case REG_BG1CNT:
621	case REG_BG2CNT:
622	case REG_BG3CNT:
623	case REG_WININ:
624	case REG_WINOUT:
625	case REG_BLDCNT:
626	case REG_BLDALPHA:
627	case REG_SOUND1CNT_LO:
628	case REG_SOUND1CNT_HI:
629	case REG_SOUND1CNT_X:
630	case REG_SOUND2CNT_LO:
631	case REG_SOUND2CNT_HI:
632	case REG_SOUND3CNT_LO:
633	case REG_SOUND3CNT_HI:
634	case REG_SOUND3CNT_X:
635	case REG_SOUND4CNT_LO:
636	case REG_SOUND4CNT_HI:
637	case REG_SOUNDCNT_LO:
638	case REG_SOUNDCNT_HI:
639	case REG_TM0CNT_HI:
640	case REG_TM1CNT_HI:
641	case REG_TM2CNT_HI:
642	case REG_TM3CNT_HI:
643	case REG_KEYINPUT:
644	case REG_IE:
645		return true;
646	}
647}
648
649uint16_t GBAIORead(struct GBA* gba, uint32_t address) {
650	if (!GBAIOIsReadConstant(address)) {
651		// Most IO reads need to disable idle removal
652		gba->haltPending = false;
653	}
654
655	switch (address) {
656	case REG_TM0CNT_LO:
657		GBATimerUpdateRegister(gba, 0);
658		break;
659	case REG_TM1CNT_LO:
660		GBATimerUpdateRegister(gba, 1);
661		break;
662	case REG_TM2CNT_LO:
663		GBATimerUpdateRegister(gba, 2);
664		break;
665	case REG_TM3CNT_LO:
666		GBATimerUpdateRegister(gba, 3);
667		break;
668
669	case REG_KEYINPUT:
670		if (gba->rr && gba->rr->isPlaying(gba->rr)) {
671			return 0x3FF ^ gba->rr->queryInput(gba->rr);
672		} else {
673			uint16_t input = 0x3FF;
674			if (gba->keyCallback) {
675				input = gba->keyCallback->readKeys(gba->keyCallback);
676			} else if (gba->keySource) {
677				input = *gba->keySource;
678			}
679			if (!gba->allowOpposingDirections) {
680				unsigned rl = input & 0x030;
681				unsigned ud = input & 0x0C0;
682				input &= 0x30F;
683				if (rl != 0x030) {
684					input |= rl;
685				}
686				if (ud != 0x0C0) {
687					input |= ud;
688				}
689			}
690			if (gba->rr && gba->rr->isRecording(gba->rr)) {
691				gba->rr->logInput(gba->rr, input);
692			}
693			return 0x3FF ^ input;
694		}
695
696	case REG_SIOCNT:
697		return gba->sio.siocnt;
698	case REG_RCNT:
699		return gba->sio.rcnt;
700
701	case REG_BG0HOFS:
702	case REG_BG0VOFS:
703	case REG_BG1HOFS:
704	case REG_BG1VOFS:
705	case REG_BG2HOFS:
706	case REG_BG2VOFS:
707	case REG_BG3HOFS:
708	case REG_BG3VOFS:
709	case REG_BG2PA:
710	case REG_BG2PB:
711	case REG_BG2PC:
712	case REG_BG2PD:
713	case REG_BG2X_LO:
714	case REG_BG2X_HI:
715	case REG_BG2Y_LO:
716	case REG_BG2Y_HI:
717	case REG_BG3PA:
718	case REG_BG3PB:
719	case REG_BG3PC:
720	case REG_BG3PD:
721	case REG_BG3X_LO:
722	case REG_BG3X_HI:
723	case REG_BG3Y_LO:
724	case REG_BG3Y_HI:
725	case REG_WIN0H:
726	case REG_WIN1H:
727	case REG_WIN0V:
728	case REG_WIN1V:
729	case REG_MOSAIC:
730	case REG_BLDY:
731	case REG_FIFO_A_LO:
732	case REG_FIFO_A_HI:
733	case REG_FIFO_B_LO:
734	case REG_FIFO_B_HI:
735	case REG_DMA0SAD_LO:
736	case REG_DMA0SAD_HI:
737	case REG_DMA0DAD_LO:
738	case REG_DMA0DAD_HI:
739	case REG_DMA0CNT_LO:
740	case REG_DMA1SAD_LO:
741	case REG_DMA1SAD_HI:
742	case REG_DMA1DAD_LO:
743	case REG_DMA1DAD_HI:
744	case REG_DMA1CNT_LO:
745	case REG_DMA2SAD_LO:
746	case REG_DMA2SAD_HI:
747	case REG_DMA2DAD_LO:
748	case REG_DMA2DAD_HI:
749	case REG_DMA2CNT_LO:
750	case REG_DMA3SAD_LO:
751	case REG_DMA3SAD_HI:
752	case REG_DMA3DAD_LO:
753	case REG_DMA3DAD_HI:
754	case REG_DMA3CNT_LO:
755		// Write-only register
756		mLOG(GBA_IO, GAME_ERROR, "Read from write-only I/O register: %03X", address);
757		return GBALoadBad(gba->cpu);
758
759	case REG_SOUNDBIAS:
760	case REG_JOYCNT:
761	case REG_JOY_RECV:
762	case REG_JOY_TRANS:
763	case REG_KEYCNT:
764	case REG_POSTFLG:
765		mLOG(GBA_IO, STUB, "Stub I/O register read: %03x", address);
766		break;
767	case REG_SOUND1CNT_LO:
768	case REG_SOUND1CNT_HI:
769	case REG_SOUND1CNT_X:
770	case REG_SOUND2CNT_LO:
771	case REG_SOUND2CNT_HI:
772	case REG_SOUND3CNT_LO:
773	case REG_SOUND3CNT_HI:
774	case REG_SOUND3CNT_X:
775	case REG_SOUND4CNT_LO:
776	case REG_SOUND4CNT_HI:
777	case REG_SOUNDCNT_LO:
778	case REG_SOUNDCNT_HI:
779		if (!GBAudioEnableIsEnable(gba->memory.io[REG_SOUNDCNT_X >> 1])) {
780			// TODO: Is writing allowed when the circuit is disabled?
781			return 0;
782		}
783		// Fall through
784	case REG_DISPCNT:
785	case REG_DISPSTAT:
786	case REG_VCOUNT:
787	case REG_BG0CNT:
788	case REG_BG1CNT:
789	case REG_BG2CNT:
790	case REG_BG3CNT:
791	case REG_WININ:
792	case REG_WINOUT:
793	case REG_BLDCNT:
794	case REG_BLDALPHA:
795	case REG_SOUNDCNT_X:
796	case REG_WAVE_RAM0_LO:
797	case REG_WAVE_RAM0_HI:
798	case REG_WAVE_RAM1_LO:
799	case REG_WAVE_RAM1_HI:
800	case REG_WAVE_RAM2_LO:
801	case REG_WAVE_RAM2_HI:
802	case REG_WAVE_RAM3_LO:
803	case REG_WAVE_RAM3_HI:
804	case REG_DMA0CNT_HI:
805	case REG_DMA1CNT_HI:
806	case REG_DMA2CNT_HI:
807	case REG_DMA3CNT_HI:
808	case REG_TM0CNT_HI:
809	case REG_TM1CNT_HI:
810	case REG_TM2CNT_HI:
811	case REG_TM3CNT_HI:
812	case REG_SIOMULTI0:
813	case REG_SIOMULTI1:
814	case REG_SIOMULTI2:
815	case REG_SIOMULTI3:
816	case REG_SIOMLT_SEND:
817	case REG_IE:
818	case REG_IF:
819	case REG_WAITCNT:
820	case REG_IME:
821		// Handled transparently by registers
822		break;
823	case REG_MAX:
824		// Some bad interrupt libraries will read from this
825		break;
826	default:
827		mLOG(GBA_IO, GAME_ERROR, "Read from unused I/O register: %03X", address);
828		return GBALoadBad(gba->cpu);
829	}
830	return gba->memory.io[address >> 1];
831}
832
833void GBAIOSerialize(struct GBA* gba, struct GBASerializedState* state) {
834	int i;
835	for (i = 0; i < REG_MAX; i += 2) {
836		if (_isRSpecialRegister[i >> 1]) {
837			STORE_16(gba->memory.io[i >> 1], i, state->io);
838		} else if (_isValidRegister[i >> 1]) {
839			uint16_t reg = GBAIORead(gba, i);
840			STORE_16(reg, i, state->io);
841		}
842	}
843
844	for (i = 0; i < 4; ++i) {
845		STORE_16(gba->memory.io[(REG_DMA0CNT_LO + i * 12) >> 1], (REG_DMA0CNT_LO + i * 12), state->io);
846		STORE_16(gba->timers[i].reload, 0, &state->timers[i].reload);
847		STORE_16(gba->timers[i].oldReload, 0, &state->timers[i].oldReload);
848		STORE_32(gba->timers[i].lastEvent, 0, &state->timers[i].lastEvent);
849		STORE_32(gba->timers[i].nextEvent, 0, &state->timers[i].nextEvent);
850		STORE_32(gba->timers[i].overflowInterval, 0, &state->timers[i].overflowInterval);
851		STORE_32(gba->timers[i].flags, 0, &state->timers[i].flags);
852		STORE_32(gba->memory.dma[i].nextSource, 0, &state->dma[i].nextSource);
853		STORE_32(gba->memory.dma[i].nextDest, 0, &state->dma[i].nextDest);
854		STORE_32(gba->memory.dma[i].nextCount, 0, &state->dma[i].nextCount);
855		STORE_32(gba->memory.dma[i].nextEvent, 0, &state->dma[i].nextEvent);
856	}
857
858	GBAHardwareSerialize(&gba->memory.hw, state);
859}
860
861void GBAIODeserialize(struct GBA* gba, const struct GBASerializedState* state) {
862	int i;
863	for (i = 0; i < REG_MAX; i += 2) {
864		if (_isWSpecialRegister[i >> 1]) {
865			LOAD_16(gba->memory.io[i >> 1], i, state->io);
866		} else if (_isValidRegister[i >> 1]) {
867			uint16_t reg;
868			LOAD_16(reg, i, state->io);
869			GBAIOWrite(gba, i, reg);
870		}
871	}
872
873	gba->timersEnabled = 0;
874	for (i = 0; i < 4; ++i) {
875		LOAD_16(gba->timers[i].reload, 0, &state->timers[i].reload);
876		LOAD_16(gba->timers[i].oldReload, 0, &state->timers[i].oldReload);
877		LOAD_32(gba->timers[i].lastEvent, 0, &state->timers[i].lastEvent);
878		LOAD_32(gba->timers[i].nextEvent, 0, &state->timers[i].nextEvent);
879		LOAD_32(gba->timers[i].overflowInterval, 0, &state->timers[i].overflowInterval);
880		LOAD_32(gba->timers[i].flags, 0, &state->timers[i].flags);
881		LOAD_16(gba->memory.dma[i].reg, (REG_DMA0CNT_HI + i * 12), state->io);
882		LOAD_32(gba->memory.dma[i].nextSource, 0, &state->dma[i].nextSource);
883		LOAD_32(gba->memory.dma[i].nextDest, 0, &state->dma[i].nextDest);
884		LOAD_32(gba->memory.dma[i].nextCount, 0, &state->dma[i].nextCount);
885		LOAD_32(gba->memory.dma[i].nextEvent, 0, &state->dma[i].nextEvent);
886		if (GBADMARegisterGetTiming(gba->memory.dma[i].reg) != DMA_TIMING_NOW) {
887			GBAMemoryScheduleDMA(gba, i, &gba->memory.dma[i]);
888		}
889
890		if (GBATimerFlagsIsEnable(gba->timers[i].flags)) {
891			gba->timersEnabled |= 1 << i;
892		}
893	}
894	GBAAudioWriteSOUNDCNT_X(&gba->audio, gba->memory.io[REG_SOUNDCNT_X >> 1]);
895	GBAMemoryUpdateDMAs(gba, 0);
896	GBAHardwareDeserialize(&gba->memory.hw, state);
897}