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