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
37MGBA_EXPORT const int GBAVideoObjSizes[16][2] = {
38 { 8, 8 },
39 { 16, 16 },
40 { 32, 32 },
41 { 64, 64 },
42 { 16, 8 },
43 { 32, 8 },
44 { 32, 16 },
45 { 64, 32 },
46 { 8, 16 },
47 { 8, 32 },
48 { 16, 32 },
49 { 32, 64 },
50 { 0, 0 },
51 { 0, 0 },
52 { 0, 0 },
53 { 0, 0 },
54};
55
56void GBAVideoInit(struct GBAVideo* video) {
57 video->renderer = NULL;
58 video->vram = anonymousMemoryMap(SIZE_VRAM);
59 video->frameskip = 0;
60 video->event.name = "GBA Video";
61 video->event.callback = NULL;
62 video->event.context = video;
63 video->event.priority = 8;
64}
65
66void GBAVideoReset(struct GBAVideo* video) {
67 int32_t nextEvent = VIDEO_HDRAW_LENGTH;
68 if (video->p->memory.fullBios) {
69 video->vcount = 0;
70 } else {
71 // TODO: Verify exact scanline on hardware
72 video->vcount = 0x7E;
73 nextEvent = 170;
74 }
75 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
76
77 video->event.callback = _startHblank;
78 mTimingSchedule(&video->p->timing, &video->event, nextEvent);
79
80 video->frameCounter = 0;
81 video->frameskipCounter = 0;
82 video->shouldStall = 0;
83
84 memset(video->palette, 0, sizeof(video->palette));
85 memset(video->oam.raw, 0, sizeof(video->oam.raw));
86
87 if (!video->renderer) {
88 mLOG(GBA_VIDEO, FATAL, "No renderer associated");
89 return;
90 }
91 video->renderer->vram = video->vram;
92 video->renderer->reset(video->renderer);
93}
94
95void GBAVideoDeinit(struct GBAVideo* video) {
96 video->renderer->deinit(video->renderer);
97 mappedMemoryFree(video->vram, SIZE_VRAM);
98}
99
100void GBAVideoDummyRendererCreate(struct GBAVideoRenderer* renderer) {
101 static const struct GBAVideoRenderer dummyRenderer = {
102 .init = GBAVideoDummyRendererInit,
103 .reset = GBAVideoDummyRendererReset,
104 .deinit = GBAVideoDummyRendererDeinit,
105 .writeVideoRegister = GBAVideoDummyRendererWriteVideoRegister,
106 .writeVRAM = GBAVideoDummyRendererWriteVRAM,
107 .writePalette = GBAVideoDummyRendererWritePalette,
108 .writeOAM = GBAVideoDummyRendererWriteOAM,
109 .drawScanline = GBAVideoDummyRendererDrawScanline,
110 .finishFrame = GBAVideoDummyRendererFinishFrame,
111 .getPixels = GBAVideoDummyRendererGetPixels,
112 .putPixels = GBAVideoDummyRendererPutPixels,
113 };
114 memcpy(renderer, &dummyRenderer, sizeof(*renderer));
115}
116
117void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
118 if (video->renderer) {
119 video->renderer->deinit(video->renderer);
120 renderer->cache = video->renderer->cache;
121 } else {
122 renderer->cache = NULL;
123 }
124 video->renderer = renderer;
125 renderer->palette = video->palette;
126 renderer->vram = video->vram;
127 renderer->oam = &video->oam;
128 video->renderer->init(video->renderer);
129 video->renderer->reset(video->renderer);
130 renderer->writeVideoRegister(renderer, REG_DISPCNT, video->p->memory.io[REG_DISPCNT >> 1]);
131 renderer->writeVideoRegister(renderer, REG_GREENSWP, video->p->memory.io[REG_GREENSWP >> 1]);
132 int address;
133 for (address = REG_BG0CNT; address < REG_SOUND1CNT_LO; address += 2) {
134 renderer->writeVideoRegister(renderer, address, video->p->memory.io[address >> 1]);
135 }
136}
137
138void _midHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
139 struct GBAVideo* video = context;
140 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
141 dispstat = GBARegisterDISPSTATClearInHblank(dispstat);
142 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
143 video->event.callback = _startHdraw;
144 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_FLIP - cyclesLate);
145}
146
147void _startHdraw(struct mTiming* timing, void* context, uint32_t cyclesLate) {
148 struct GBAVideo* video = context;
149 video->event.callback = _startHblank;
150 mTimingSchedule(timing, &video->event, VIDEO_HDRAW_LENGTH - cyclesLate);
151
152 ++video->vcount;
153 if (video->vcount == VIDEO_VERTICAL_TOTAL_PIXELS) {
154 video->vcount = 0;
155 }
156 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
157
158 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS) {
159 if (video->frameskipCounter <= 0) {
160 video->renderer->drawScanline(video->renderer, video->vcount);
161 }
162 video->shouldStall = 1;
163 }
164
165 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
166 if (video->vcount == GBARegisterDISPSTATGetVcountSetting(dispstat)) {
167 dispstat = GBARegisterDISPSTATFillVcounter(dispstat);
168 if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
169 GBARaiseIRQ(video->p, IRQ_VCOUNTER, cyclesLate);
170 }
171 } else {
172 dispstat = GBARegisterDISPSTATClearVcounter(dispstat);
173 }
174 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
175
176 // Note: state may be recorded during callbacks, so ensure it is consistent!
177 switch (video->vcount) {
178 case 0:
179 GBAFrameStarted(video->p);
180 break;
181 case GBA_VIDEO_VERTICAL_PIXELS:
182 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATFillInVblank(dispstat);
183 if (video->frameskipCounter <= 0) {
184 video->renderer->finishFrame(video->renderer);
185 }
186 GBADMARunVblank(video->p, -cyclesLate);
187 if (GBARegisterDISPSTATIsVblankIRQ(dispstat)) {
188 GBARaiseIRQ(video->p, IRQ_VBLANK, cyclesLate);
189 }
190 GBAFrameEnded(video->p);
191 mCoreSyncPostFrame(video->p->sync);
192 --video->frameskipCounter;
193 if (video->frameskipCounter < 0) {
194 video->frameskipCounter = video->frameskip;
195 }
196 ++video->frameCounter;
197 video->p->earlyExit = true;
198 break;
199 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
200 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATClearInVblank(dispstat);
201 break;
202 }
203}
204
205void _startHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
206 struct GBAVideo* video = context;
207 video->event.callback = _midHblank;
208 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_LENGTH - VIDEO_HBLANK_FLIP - cyclesLate);
209
210 // Begin Hblank
211 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
212 dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
213
214 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS) {
215 GBADMARunHblank(video->p, -cyclesLate);
216 }
217 if (video->vcount >= 2 && video->vcount < GBA_VIDEO_VERTICAL_PIXELS + 2) {
218 GBADMARunDisplayStart(video->p, -cyclesLate);
219 }
220 if (GBARegisterDISPSTATIsHblankIRQ(dispstat)) {
221 GBARaiseIRQ(video->p, IRQ_HBLANK, cyclesLate);
222 }
223 video->shouldStall = 0;
224 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
225}
226
227void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
228 video->p->memory.io[REG_DISPSTAT >> 1] &= 0x7;
229 video->p->memory.io[REG_DISPSTAT >> 1] |= value;
230 // TODO: Does a VCounter IRQ trigger on write?
231}
232
233static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
234 UNUSED(renderer);
235 // Nothing to do
236}
237
238static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
239 UNUSED(renderer);
240 // Nothing to do
241}
242
243static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
244 UNUSED(renderer);
245 // Nothing to do
246}
247
248static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
249 if (renderer->cache) {
250 GBAVideoCacheWriteVideoRegister(renderer->cache, address, value);
251 }
252 switch (address) {
253 case REG_DISPCNT:
254 value &= 0xFFF7;
255 break;
256 case REG_BG0CNT:
257 case REG_BG1CNT:
258 value &= 0xDFFF;
259 break;
260 case REG_BG2CNT:
261 case REG_BG3CNT:
262 value &= 0xFFFF;
263 break;
264 case REG_BG0HOFS:
265 case REG_BG0VOFS:
266 case REG_BG1HOFS:
267 case REG_BG1VOFS:
268 case REG_BG2HOFS:
269 case REG_BG2VOFS:
270 case REG_BG3HOFS:
271 case REG_BG3VOFS:
272 value &= 0x01FF;
273 break;
274 case REG_BLDCNT:
275 value &= 0x3FFF;
276 break;
277 case REG_BLDALPHA:
278 value &= 0x1F1F;
279 break;
280 case REG_WININ:
281 case REG_WINOUT:
282 value &= 0x3F3F;
283 break;
284 default:
285 break;
286 }
287 return value;
288}
289
290static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
291 if (renderer->cache) {
292 mCacheSetWriteVRAM(renderer->cache, address);
293 }
294}
295
296static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
297 if (renderer->cache) {
298 mCacheSetWritePalette(renderer->cache, address >> 1, mColorFrom555(value));
299 }
300}
301
302static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
303 UNUSED(renderer);
304 UNUSED(oam);
305 // Nothing to do
306}
307
308static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
309 UNUSED(renderer);
310 UNUSED(y);
311 // Nothing to do
312}
313
314static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
315 UNUSED(renderer);
316 // Nothing to do
317}
318
319static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels) {
320 UNUSED(renderer);
321 UNUSED(stride);
322 UNUSED(pixels);
323 // Nothing to do
324}
325
326static void GBAVideoDummyRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels) {
327 UNUSED(renderer);
328 UNUSED(stride);
329 UNUSED(pixels);
330 // Nothing to do
331}
332
333void GBAVideoSerialize(const struct GBAVideo* video, struct GBASerializedState* state) {
334 memcpy(state->vram, video->vram, SIZE_VRAM);
335 memcpy(state->oam, video->oam.raw, SIZE_OAM);
336 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
337 STORE_32(video->event.when - mTimingCurrentTime(&video->p->timing), 0, &state->video.nextEvent);
338 int32_t flags = 0;
339 if (video->event.callback == _startHdraw) {
340 flags = GBASerializedVideoFlagsSetMode(flags, 1);
341 } else if (video->event.callback == _startHblank) {
342 flags = GBASerializedVideoFlagsSetMode(flags, 2);
343 } else if (video->event.callback == _midHblank) {
344 flags = GBASerializedVideoFlagsSetMode(flags, 3);
345 }
346 STORE_32(flags, 0, &state->video.flags);
347 STORE_32(video->frameCounter, 0, &state->video.frameCounter);
348}
349
350void GBAVideoDeserialize(struct GBAVideo* video, const struct GBASerializedState* state) {
351 memcpy(video->vram, state->vram, SIZE_VRAM);
352 uint16_t value;
353 int i;
354 for (i = 0; i < SIZE_OAM; i += 2) {
355 LOAD_16(value, i, state->oam);
356 GBAStore16(video->p->cpu, BASE_OAM | i, value, 0);
357 }
358 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
359 LOAD_16(value, i, state->pram);
360 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, value, 0);
361 }
362 LOAD_32(video->frameCounter, 0, &state->video.frameCounter);
363
364 video->shouldStall = 0;
365 int32_t flags;
366 LOAD_32(flags, 0, &state->video.flags);
367 GBARegisterDISPSTAT dispstat = state->io[REG_DISPSTAT >> 1];
368 switch (GBASerializedVideoFlagsGetMode(flags)) {
369 case 0:
370 if (GBARegisterDISPSTATIsInHblank(dispstat)) {
371 video->event.callback = _startHdraw;
372 } else {
373 video->event.callback = _startHblank;
374 }
375 break;
376 case 1:
377 video->event.callback = _startHdraw;
378 break;
379 case 2:
380 video->event.callback = _startHblank;
381 video->shouldStall = 1;
382 break;
383 case 3:
384 video->event.callback = _midHblank;
385 break;
386 }
387 uint32_t when;
388 LOAD_32(when, 0, &state->video.nextEvent);
389 mTimingSchedule(&video->p->timing, &video->event, when);
390
391 LOAD_16(video->vcount, REG_VCOUNT, state->io);
392 video->renderer->reset(video->renderer);
393}