src/gba/video.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 <mgba/internal/gba/video.h>
7
8#include <mgba/core/sync.h>
9#include <mgba/core/cache-set.h>
10#include <mgba/internal/arm/macros.h>
11#include <mgba/internal/gba/dma.h>
12#include <mgba/internal/gba/gba.h>
13#include <mgba/internal/gba/io.h>
14#include <mgba/internal/gba/renderers/cache-set.h>
15#include <mgba/internal/gba/serialize.h>
16
17#include <mgba-util/memory.h>
18
19mLOG_DEFINE_CATEGORY(GBA_VIDEO, "GBA Video", "gba.video");
20
21static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer);
22static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer);
23static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer);
24static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
25static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address);
26static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
27static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam);
28static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y);
29static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer);
30static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels);
31static void GBAVideoDummyRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels);
32
33static void _startHblank(struct mTiming*, void* context, uint32_t cyclesLate);
34static void _midHblank(struct mTiming*, void* context, uint32_t cyclesLate);
35static void _startHdraw(struct mTiming*, void* context, uint32_t cyclesLate);
36
37static uint16_t _zeroes[0x2000] = {0};
38
39MGBA_EXPORT const int GBAVideoObjSizes[16][2] = {
40 { 8, 8 },
41 { 16, 16 },
42 { 32, 32 },
43 { 64, 64 },
44 { 16, 8 },
45 { 32, 8 },
46 { 32, 16 },
47 { 64, 32 },
48 { 8, 16 },
49 { 8, 32 },
50 { 16, 32 },
51 { 32, 64 },
52 { 0, 0 },
53 { 0, 0 },
54 { 0, 0 },
55 { 0, 0 },
56};
57
58static struct GBAVideoRenderer dummyRenderer = {
59 .init = GBAVideoDummyRendererInit,
60 .reset = GBAVideoDummyRendererReset,
61 .deinit = GBAVideoDummyRendererDeinit,
62 .writeVideoRegister = GBAVideoDummyRendererWriteVideoRegister,
63 .writeVRAM = GBAVideoDummyRendererWriteVRAM,
64 .writePalette = GBAVideoDummyRendererWritePalette,
65 .writeOAM = GBAVideoDummyRendererWriteOAM,
66 .drawScanline = GBAVideoDummyRendererDrawScanline,
67 .finishFrame = GBAVideoDummyRendererFinishFrame,
68 .getPixels = GBAVideoDummyRendererGetPixels,
69 .putPixels = GBAVideoDummyRendererPutPixels,
70};
71
72void GBAVideoInit(struct GBAVideo* video) {
73 video->renderer = &dummyRenderer;
74 video->renderer->cache = NULL;
75 video->vram = anonymousMemoryMap(SIZE_VRAM);
76 video->frameskip = 0;
77 video->event.name = "GBA Video";
78 video->event.callback = NULL;
79 video->event.context = video;
80 video->event.priority = 8;
81}
82
83void GBAVideoReset(struct GBAVideo* video) {
84 int32_t nextEvent = VIDEO_HDRAW_LENGTH;
85 if (video->p->memory.fullBios) {
86 video->vcount = 0;
87 } else {
88 // TODO: Verify exact scanline on hardware
89 video->vcount = 0x7E;
90 nextEvent = 170;
91 }
92 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
93
94 video->event.callback = _startHblank;
95 mTimingSchedule(&video->p->timing, &video->event, nextEvent);
96
97 video->frameCounter = 0;
98 video->frameskipCounter = 0;
99
100 memset(video->renderer->vramBG, 0, sizeof(video->renderer->vramBG));
101 video->renderer->vramBG[0] = &video->vram[0x0000];
102 video->renderer->vramBG[1] = &video->vram[0x2000];
103 video->renderer->vramBG[2] = &video->vram[0x4000];
104 video->renderer->vramBG[3] = &video->vram[0x6000];
105 memset(video->renderer->vramOBJ, 0, sizeof(video->renderer->vramOBJ));
106 video->renderer->vramOBJ[0] = &video->vram[0x8000];
107 video->renderer->vramOBJ[1] = &video->vram[0xA000];
108 video->renderer->vramOBJ[2] = _zeroes;
109 video->renderer->vramOBJ[3] = _zeroes;
110 video->shouldStall = 0;
111
112 memset(video->palette, 0, sizeof(video->palette));
113 memset(video->oam.raw, 0, sizeof(video->oam.raw));
114
115 video->renderer->reset(video->renderer);
116}
117
118void GBAVideoDeinit(struct GBAVideo* video) {
119 video->renderer->deinit(video->renderer);
120 mappedMemoryFree(video->vram, SIZE_VRAM);
121}
122
123void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
124 video->renderer->deinit(video->renderer);
125 renderer->cache = video->renderer->cache;
126 video->renderer = renderer;
127 renderer->palette = video->palette;
128 memset(renderer->vramBG, 0, sizeof(renderer->vramBG));
129 renderer->vramBG[0] = &video->vram[0x0000];
130 renderer->vramBG[1] = &video->vram[0x2000];
131 renderer->vramBG[2] = &video->vram[0x4000];
132 renderer->vramBG[3] = &video->vram[0x6000];
133 memset(renderer->vramOBJ, 0, sizeof(renderer->vramOBJ));
134 renderer->vramOBJ[0] = &video->vram[0x8000];
135 renderer->vramOBJ[1] = &video->vram[0xA000];
136 renderer->vramOBJ[2] = _zeroes;
137 renderer->vramOBJ[3] = _zeroes;
138 renderer->oam = &video->oam;
139 video->renderer->init(video->renderer);
140}
141
142void _midHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
143 struct GBAVideo* video = context;
144 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
145 dispstat = GBARegisterDISPSTATClearInHblank(dispstat);
146 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
147 video->event.callback = _startHdraw;
148 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_FLIP - cyclesLate);
149}
150
151void _startHdraw(struct mTiming* timing, void* context, uint32_t cyclesLate) {
152 struct GBAVideo* video = context;
153 video->event.callback = _startHblank;
154 mTimingSchedule(timing, &video->event, VIDEO_HDRAW_LENGTH - cyclesLate);
155
156 ++video->vcount;
157 if (video->vcount == VIDEO_VERTICAL_TOTAL_PIXELS) {
158 video->vcount = 0;
159 }
160 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
161
162 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS && video->frameskipCounter <= 0) {
163 video->renderer->drawScanline(video->renderer, video->vcount);
164 video->shouldStall = 1;
165 }
166
167 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
168 if (video->vcount == GBARegisterDISPSTATGetVcountSetting(dispstat)) {
169 dispstat = GBARegisterDISPSTATFillVcounter(dispstat);
170 if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
171 GBARaiseIRQ(video->p, IRQ_VCOUNTER, cyclesLate);
172 }
173 } else {
174 dispstat = GBARegisterDISPSTATClearVcounter(dispstat);
175 }
176 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
177
178 // Note: state may be recorded during callbacks, so ensure it is consistent!
179 switch (video->vcount) {
180 case 0:
181 GBAFrameStarted(video->p);
182 break;
183 case GBA_VIDEO_VERTICAL_PIXELS:
184 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATFillInVblank(dispstat);
185 if (video->frameskipCounter <= 0) {
186 video->renderer->finishFrame(video->renderer);
187 }
188 GBADMARunVblank(video->p, -cyclesLate);
189 if (GBARegisterDISPSTATIsVblankIRQ(dispstat)) {
190 GBARaiseIRQ(video->p, IRQ_VBLANK, cyclesLate);
191 }
192 GBAFrameEnded(video->p);
193 mCoreSyncPostFrame(video->p->sync);
194 --video->frameskipCounter;
195 if (video->frameskipCounter < 0) {
196 video->frameskipCounter = video->frameskip;
197 }
198 ++video->frameCounter;
199 break;
200 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
201 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATClearInVblank(dispstat);
202 break;
203 }
204}
205
206void _startHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
207 struct GBAVideo* video = context;
208 video->event.callback = _midHblank;
209 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_LENGTH - VIDEO_HBLANK_FLIP - cyclesLate);
210
211 // Begin Hblank
212 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
213 dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
214
215 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS) {
216 GBADMARunHblank(video->p, -cyclesLate);
217 }
218 if (video->vcount >= 2 && video->vcount < GBA_VIDEO_VERTICAL_PIXELS + 2) {
219 GBADMARunDisplayStart(video->p, -cyclesLate);
220 }
221 if (GBARegisterDISPSTATIsHblankIRQ(dispstat)) {
222 GBARaiseIRQ(video->p, IRQ_HBLANK, cyclesLate);
223 }
224 video->shouldStall = 0;
225 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
226}
227
228void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
229 video->p->memory.io[REG_DISPSTAT >> 1] &= 0x7;
230 video->p->memory.io[REG_DISPSTAT >> 1] |= value;
231 // TODO: Does a VCounter IRQ trigger on write?
232}
233
234static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
235 UNUSED(renderer);
236 // Nothing to do
237}
238
239static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
240 UNUSED(renderer);
241 // Nothing to do
242}
243
244static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
245 UNUSED(renderer);
246 // Nothing to do
247}
248
249static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
250 if (renderer->cache) {
251 GBAVideoCacheWriteVideoRegister(renderer->cache, address, value);
252 }
253 switch (address) {
254 case REG_DISPCNT:
255 value &= 0xFFF7;
256 break;
257 case REG_BG0CNT:
258 case REG_BG1CNT:
259 value &= 0xDFFF;
260 break;
261 case REG_BG2CNT:
262 case REG_BG3CNT:
263 value &= 0xFFFF;
264 break;
265 case REG_BG0HOFS:
266 case REG_BG0VOFS:
267 case REG_BG1HOFS:
268 case REG_BG1VOFS:
269 case REG_BG2HOFS:
270 case REG_BG2VOFS:
271 case REG_BG3HOFS:
272 case REG_BG3VOFS:
273 value &= 0x01FF;
274 break;
275 case REG_BLDCNT:
276 value &= 0x3FFF;
277 break;
278 case REG_BLDALPHA:
279 value &= 0x1F1F;
280 break;
281 case REG_WININ:
282 case REG_WINOUT:
283 value &= 0x3F3F;
284 break;
285 default:
286 break;
287 }
288 return value;
289}
290
291static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
292 if (renderer->cache) {
293 mCacheSetWriteVRAM(renderer->cache, address);
294 }
295}
296
297static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
298 if (renderer->cache) {
299 mCacheSetWritePalette(renderer->cache, address >> 1, mColorFrom555(value));
300 }
301}
302
303static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
304 UNUSED(renderer);
305 UNUSED(oam);
306 // Nothing to do
307}
308
309static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
310 UNUSED(renderer);
311 UNUSED(y);
312 // Nothing to do
313}
314
315static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
316 UNUSED(renderer);
317 // Nothing to do
318}
319
320static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels) {
321 UNUSED(renderer);
322 UNUSED(stride);
323 UNUSED(pixels);
324 // Nothing to do
325}
326
327static void GBAVideoDummyRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels) {
328 UNUSED(renderer);
329 UNUSED(stride);
330 UNUSED(pixels);
331 // Nothing to do
332}
333
334void GBAVideoSerialize(const struct GBAVideo* video, struct GBASerializedState* state) {
335 memcpy(state->vram, video->vram, SIZE_VRAM);
336 memcpy(state->oam, video->oam.raw, SIZE_OAM);
337 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
338 STORE_32(video->event.when - mTimingCurrentTime(&video->p->timing), 0, &state->video.nextEvent);
339 int32_t flags = 0;
340 if (video->event.callback == _startHdraw) {
341 flags = GBASerializedVideoFlagsSetMode(flags, 1);
342 } else if (video->event.callback == _startHblank) {
343 flags = GBASerializedVideoFlagsSetMode(flags, 2);
344 } else if (video->event.callback == _midHblank) {
345 flags = GBASerializedVideoFlagsSetMode(flags, 3);
346 }
347 STORE_32(flags, 0, &state->video.flags);
348 STORE_32(video->frameCounter, 0, &state->video.frameCounter);
349}
350
351void GBAVideoDeserialize(struct GBAVideo* video, const struct GBASerializedState* state) {
352 memcpy(video->vram, state->vram, SIZE_VRAM);
353 uint16_t value;
354 int i;
355 for (i = 0; i < SIZE_OAM; i += 2) {
356 LOAD_16(value, i, state->oam);
357 GBAStore16(video->p->cpu, BASE_OAM | i, value, 0);
358 }
359 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
360 LOAD_16(value, i, state->pram);
361 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, value, 0);
362 }
363 LOAD_32(video->frameCounter, 0, &state->video.frameCounter);
364
365 video->shouldStall = 0;
366 int32_t flags;
367 LOAD_32(flags, 0, &state->video.flags);
368 GBARegisterDISPSTAT dispstat = state->io[REG_DISPSTAT >> 1];
369 switch (GBASerializedVideoFlagsGetMode(flags)) {
370 case 0:
371 if (GBARegisterDISPSTATIsInHblank(dispstat)) {
372 video->event.callback = _startHdraw;
373 } else {
374 video->event.callback = _startHblank;
375 }
376 break;
377 case 1:
378 video->event.callback = _startHdraw;
379 break;
380 case 2:
381 video->event.callback = _startHblank;
382 video->shouldStall = 1;
383 break;
384 case 3:
385 video->event.callback = _midHblank;
386 break;
387 }
388 uint32_t when;
389 LOAD_32(when, 0, &state->video.nextEvent);
390 mTimingSchedule(&video->p->timing, &video->event, when);
391
392 LOAD_16(video->vcount, REG_VCOUNT, state->io);
393 video->renderer->reset(video->renderer);
394}