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