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