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] = {};
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
111 memset(video->palette, 0, sizeof(video->palette));
112 memset(video->oam.raw, 0, sizeof(video->oam.raw));
113
114 video->renderer->reset(video->renderer);
115}
116
117void GBAVideoDeinit(struct GBAVideo* video) {
118 video->renderer->deinit(video->renderer);
119 mappedMemoryFree(video->vram, SIZE_VRAM);
120}
121
122void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
123 video->renderer->deinit(video->renderer);
124 renderer->cache = video->renderer->cache;
125 video->renderer = renderer;
126 renderer->palette = video->palette;
127 memset(renderer->vramBG, 0, sizeof(renderer->vramBG));
128 renderer->vramBG[0] = &video->vram[0x0000];
129 renderer->vramBG[1] = &video->vram[0x2000];
130 renderer->vramBG[2] = &video->vram[0x4000];
131 renderer->vramBG[3] = &video->vram[0x6000];
132 memset(renderer->vramOBJ, 0, sizeof(renderer->vramOBJ));
133 renderer->vramOBJ[0] = &video->vram[0x8000];
134 renderer->vramOBJ[1] = &video->vram[0xA000];
135 renderer->vramOBJ[2] = _zeroes;
136 renderer->vramOBJ[3] = _zeroes;
137 renderer->oam = &video->oam;
138 video->renderer->init(video->renderer);
139}
140
141void _midHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
142 struct GBAVideo* video = context;
143 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
144 dispstat = GBARegisterDISPSTATClearInHblank(dispstat);
145 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
146 video->event.callback = _startHdraw;
147 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_FLIP - cyclesLate);
148}
149
150void _startHdraw(struct mTiming* timing, void* context, uint32_t cyclesLate) {
151 struct GBAVideo* video = context;
152 video->event.callback = _startHblank;
153 mTimingSchedule(timing, &video->event, VIDEO_HDRAW_LENGTH - cyclesLate);
154
155 ++video->vcount;
156 if (video->vcount == VIDEO_VERTICAL_TOTAL_PIXELS) {
157 video->vcount = 0;
158 }
159 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
160
161 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS && video->frameskipCounter <= 0) {
162 video->renderer->drawScanline(video->renderer, video->vcount);
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 break;
198 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
199 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATClearInVblank(dispstat);
200 break;
201 }
202}
203
204void _startHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
205 struct GBAVideo* video = context;
206 video->event.callback = _midHblank;
207 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_LENGTH - VIDEO_HBLANK_FLIP - cyclesLate);
208
209 // Begin Hblank
210 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
211 dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
212
213 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS) {
214 GBADMARunHblank(video->p, -cyclesLate);
215 }
216 if (video->vcount >= 2 && video->vcount < GBA_VIDEO_VERTICAL_PIXELS + 2) {
217 GBADMARunDisplayStart(video->p, -cyclesLate);
218 }
219 if (GBARegisterDISPSTATIsHblankIRQ(dispstat)) {
220 GBARaiseIRQ(video->p, IRQ_HBLANK, cyclesLate);
221 }
222 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
223}
224
225void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
226 video->p->memory.io[REG_DISPSTAT >> 1] &= 0x7;
227 video->p->memory.io[REG_DISPSTAT >> 1] |= value;
228 // TODO: Does a VCounter IRQ trigger on write?
229}
230
231static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
232 UNUSED(renderer);
233 // Nothing to do
234}
235
236static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
237 UNUSED(renderer);
238 // Nothing to do
239}
240
241static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
242 UNUSED(renderer);
243 // Nothing to do
244}
245
246static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
247 if (renderer->cache) {
248 GBAVideoCacheWriteVideoRegister(renderer->cache, address, value);
249 }
250 switch (address) {
251 case REG_DISPCNT:
252 value &= 0xFFF7;
253 break;
254 case REG_BG0CNT:
255 case REG_BG1CNT:
256 value &= 0xDFFF;
257 break;
258 case REG_BG2CNT:
259 case REG_BG3CNT:
260 value &= 0xFFFF;
261 break;
262 case REG_BG0HOFS:
263 case REG_BG0VOFS:
264 case REG_BG1HOFS:
265 case REG_BG1VOFS:
266 case REG_BG2HOFS:
267 case REG_BG2VOFS:
268 case REG_BG3HOFS:
269 case REG_BG3VOFS:
270 value &= 0x01FF;
271 break;
272 case REG_BLDCNT:
273 value &= 0x3FFF;
274 break;
275 case REG_BLDALPHA:
276 value &= 0x1F1F;
277 break;
278 case REG_WININ:
279 case REG_WINOUT:
280 value &= 0x3F3F;
281 break;
282 default:
283 break;
284 }
285 return value;
286}
287
288static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
289 if (renderer->cache) {
290 mCacheSetWriteVRAM(renderer->cache, address);
291 }
292}
293
294static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
295 if (renderer->cache) {
296 mCacheSetWritePalette(renderer->cache, address >> 1, mColorFrom555(value));
297 }
298}
299
300static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
301 UNUSED(renderer);
302 UNUSED(oam);
303 // Nothing to do
304}
305
306static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
307 UNUSED(renderer);
308 UNUSED(y);
309 // Nothing to do
310}
311
312static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
313 UNUSED(renderer);
314 // Nothing to do
315}
316
317static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels) {
318 UNUSED(renderer);
319 UNUSED(stride);
320 UNUSED(pixels);
321 // Nothing to do
322}
323
324static void GBAVideoDummyRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels) {
325 UNUSED(renderer);
326 UNUSED(stride);
327 UNUSED(pixels);
328 // Nothing to do
329}
330
331void GBAVideoSerialize(const struct GBAVideo* video, struct GBASerializedState* state) {
332 memcpy(state->vram, video->vram, SIZE_VRAM);
333 memcpy(state->oam, video->oam.raw, SIZE_OAM);
334 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
335 STORE_32(video->event.when - mTimingCurrentTime(&video->p->timing), 0, &state->video.nextEvent);
336 int32_t flags = 0;
337 if (video->event.callback == _startHdraw) {
338 flags = GBASerializedVideoFlagsSetMode(flags, 1);
339 } else if (video->event.callback == _startHblank) {
340 flags = GBASerializedVideoFlagsSetMode(flags, 2);
341 } else if (video->event.callback == _midHblank) {
342 flags = GBASerializedVideoFlagsSetMode(flags, 3);
343 }
344 STORE_32(flags, 0, &state->video.flags);
345 STORE_32(video->frameCounter, 0, &state->video.frameCounter);
346}
347
348void GBAVideoDeserialize(struct GBAVideo* video, const struct GBASerializedState* state) {
349 memcpy(video->vram, state->vram, SIZE_VRAM);
350 uint16_t value;
351 int i;
352 for (i = 0; i < SIZE_OAM; i += 2) {
353 LOAD_16(value, i, state->oam);
354 GBAStore16(video->p->cpu, BASE_OAM | i, value, 0);
355 }
356 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
357 LOAD_16(value, i, state->pram);
358 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, value, 0);
359 }
360 LOAD_32(video->frameCounter, 0, &state->video.frameCounter);
361
362 int32_t flags;
363 LOAD_32(flags, 0, &state->video.flags);
364 GBARegisterDISPSTAT dispstat = state->io[REG_DISPSTAT >> 1];
365 switch (GBASerializedVideoFlagsGetMode(flags)) {
366 case 0:
367 if (GBARegisterDISPSTATIsInHblank(dispstat)) {
368 video->event.callback = _startHdraw;
369 } else {
370 video->event.callback = _startHblank;
371 }
372 break;
373 case 1:
374 video->event.callback = _startHdraw;
375 break;
376 case 2:
377 video->event.callback = _startHblank;
378 break;
379 case 3:
380 video->event.callback = _midHblank;
381 break;
382 }
383 uint32_t when;
384 LOAD_32(when, 0, &state->video.nextEvent);
385 mTimingSchedule(&video->p->timing, &video->event, when);
386
387 LOAD_16(video->vcount, REG_VCOUNT, state->io);
388 video->renderer->reset(video->renderer);
389}