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
36const int GBAVideoObjSizes[16][2] = {
37 { 8, 8 },
38 { 16, 16 },
39 { 32, 32 },
40 { 64, 64 },
41 { 16, 8 },
42 { 32, 8 },
43 { 32, 16 },
44 { 64, 32 },
45 { 8, 16 },
46 { 8, 32 },
47 { 16, 32 },
48 { 32, 64 },
49 { 0, 0 },
50 { 0, 0 },
51 { 0, 0 },
52 { 0, 0 },
53};
54
55static struct GBAVideoRenderer dummyRenderer = {
56 .init = GBAVideoDummyRendererInit,
57 .reset = GBAVideoDummyRendererReset,
58 .deinit = GBAVideoDummyRendererDeinit,
59 .writeVideoRegister = GBAVideoDummyRendererWriteVideoRegister,
60 .writeVRAM = GBAVideoDummyRendererWriteVRAM,
61 .writePalette = GBAVideoDummyRendererWritePalette,
62 .writeOAM = GBAVideoDummyRendererWriteOAM,
63 .drawScanline = GBAVideoDummyRendererDrawScanline,
64 .finishFrame = GBAVideoDummyRendererFinishFrame,
65 .getPixels = GBAVideoDummyRendererGetPixels,
66 .putPixels = GBAVideoDummyRendererPutPixels,
67};
68
69void GBAVideoInit(struct GBAVideo* video) {
70 video->renderer = &dummyRenderer;
71 video->renderer->cache = NULL;
72 video->vram = anonymousMemoryMap(SIZE_VRAM);
73 video->frameskip = 0;
74 video->event.name = "GBA Video";
75 video->event.callback = NULL;
76 video->event.context = video;
77 video->event.priority = 8;
78}
79
80void GBAVideoReset(struct GBAVideo* video) {
81 int32_t nextEvent = VIDEO_HDRAW_LENGTH;
82 if (video->p->memory.fullBios) {
83 video->vcount = 0;
84 } else {
85 // TODO: Verify exact scanline on hardware
86 video->vcount = 0x7E;
87 nextEvent = 170;
88 }
89 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
90
91 video->event.callback = _startHblank;
92 mTimingSchedule(&video->p->timing, &video->event, nextEvent);
93
94 video->frameCounter = 0;
95 video->frameskipCounter = 0;
96 video->renderer->vram = video->vram;
97
98 memset(video->palette, 0, sizeof(video->palette));
99 memset(video->oam.raw, 0, sizeof(video->oam.raw));
100
101 video->renderer->reset(video->renderer);
102}
103
104void GBAVideoDeinit(struct GBAVideo* video) {
105 video->renderer->deinit(video->renderer);
106 mappedMemoryFree(video->vram, SIZE_VRAM);
107}
108
109void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
110 video->renderer->deinit(video->renderer);
111 renderer->cache = video->renderer->cache;
112 video->renderer = renderer;
113 renderer->palette = video->palette;
114 renderer->vram = video->vram;
115 renderer->oam = &video->oam;
116 video->renderer->init(video->renderer);
117}
118
119void _startHdraw(struct mTiming* timing, void* context, uint32_t cyclesLate) {
120 struct GBAVideo* video = context;
121 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
122 dispstat = GBARegisterDISPSTATClearInHblank(dispstat);
123 video->event.callback = _startHblank;
124 mTimingSchedule(timing, &video->event, VIDEO_HDRAW_LENGTH - cyclesLate);
125
126 ++video->vcount;
127 if (video->vcount == VIDEO_VERTICAL_TOTAL_PIXELS) {
128 video->vcount = 0;
129 }
130 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
131
132 if (video->vcount == GBARegisterDISPSTATGetVcountSetting(dispstat)) {
133 dispstat = GBARegisterDISPSTATFillVcounter(dispstat);
134 if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
135 GBARaiseIRQ(video->p, IRQ_VCOUNTER, cyclesLate);
136 }
137 } else {
138 dispstat = GBARegisterDISPSTATClearVcounter(dispstat);
139 }
140 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
141
142 // Note: state may be recorded during callbacks, so ensure it is consistent!
143 switch (video->vcount) {
144 case 0:
145 GBAFrameStarted(video->p);
146 break;
147 case GBA_VIDEO_VERTICAL_PIXELS:
148 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATFillInVblank(dispstat);
149 if (video->frameskipCounter <= 0) {
150 video->renderer->finishFrame(video->renderer);
151 }
152 GBADMARunVblank(video->p, -cyclesLate);
153 if (GBARegisterDISPSTATIsVblankIRQ(dispstat)) {
154 GBARaiseIRQ(video->p, IRQ_VBLANK, cyclesLate);
155 }
156 GBAFrameEnded(video->p);
157 mCoreSyncPostFrame(video->p->sync);
158 --video->frameskipCounter;
159 if (video->frameskipCounter < 0) {
160 video->frameskipCounter = video->frameskip;
161 }
162 ++video->frameCounter;
163 break;
164 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
165 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATClearInVblank(dispstat);
166 break;
167 }
168}
169
170void _startHblank(struct mTiming* timing, void* context, uint32_t cyclesLate) {
171 struct GBAVideo* video = context;
172 GBARegisterDISPSTAT dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
173 dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
174 video->event.callback = _startHdraw;
175 mTimingSchedule(timing, &video->event, VIDEO_HBLANK_LENGTH - cyclesLate);
176
177 // Begin Hblank
178 dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
179 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS && video->frameskipCounter <= 0) {
180 video->renderer->drawScanline(video->renderer, video->vcount);
181 }
182
183 if (video->vcount < GBA_VIDEO_VERTICAL_PIXELS) {
184 GBADMARunHblank(video->p, -cyclesLate);
185 }
186 if (video->vcount >= 2 && video->vcount < GBA_VIDEO_VERTICAL_PIXELS + 2) {
187 GBADMARunDisplayStart(video->p, -cyclesLate);
188 }
189 if (GBARegisterDISPSTATIsHblankIRQ(dispstat)) {
190 GBARaiseIRQ(video->p, IRQ_HBLANK, cyclesLate);
191 }
192 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
193}
194
195void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
196 video->p->memory.io[REG_DISPSTAT >> 1] &= 0x7;
197 video->p->memory.io[REG_DISPSTAT >> 1] |= value;
198 // TODO: Does a VCounter IRQ trigger on write?
199}
200
201static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
202 UNUSED(renderer);
203 // Nothing to do
204}
205
206static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
207 UNUSED(renderer);
208 // Nothing to do
209}
210
211static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
212 UNUSED(renderer);
213 // Nothing to do
214}
215
216static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
217 if (renderer->cache) {
218 GBAVideoCacheWriteVideoRegister(renderer->cache, address, value);
219 }
220 switch (address) {
221 case REG_DISPCNT:
222 value &= 0xFFF7;
223 break;
224 case REG_BG0CNT:
225 case REG_BG1CNT:
226 value &= 0xDFFF;
227 break;
228 case REG_BG2CNT:
229 case REG_BG3CNT:
230 value &= 0xFFFF;
231 break;
232 case REG_BG0HOFS:
233 case REG_BG0VOFS:
234 case REG_BG1HOFS:
235 case REG_BG1VOFS:
236 case REG_BG2HOFS:
237 case REG_BG2VOFS:
238 case REG_BG3HOFS:
239 case REG_BG3VOFS:
240 value &= 0x01FF;
241 break;
242 case REG_BLDCNT:
243 value &= 0x3FFF;
244 break;
245 case REG_BLDALPHA:
246 value &= 0x1F1F;
247 break;
248 case REG_WININ:
249 case REG_WINOUT:
250 value &= 0x3F3F;
251 break;
252 default:
253 break;
254 }
255 return value;
256}
257
258static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
259 if (renderer->cache) {
260 mCacheSetWriteVRAM(renderer->cache, address);
261 }
262}
263
264static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
265 if (renderer->cache) {
266 mCacheSetWritePalette(renderer->cache, address >> 1, mColorFrom555(value));
267 }
268}
269
270static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
271 UNUSED(renderer);
272 UNUSED(oam);
273 // Nothing to do
274}
275
276static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
277 UNUSED(renderer);
278 UNUSED(y);
279 // Nothing to do
280}
281
282static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
283 UNUSED(renderer);
284 // Nothing to do
285}
286
287static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, size_t* stride, const void** pixels) {
288 UNUSED(renderer);
289 UNUSED(stride);
290 UNUSED(pixels);
291 // Nothing to do
292}
293
294static void GBAVideoDummyRendererPutPixels(struct GBAVideoRenderer* renderer, size_t stride, const void* pixels) {
295 UNUSED(renderer);
296 UNUSED(stride);
297 UNUSED(pixels);
298 // Nothing to do
299}
300
301void GBAVideoSerialize(const struct GBAVideo* video, struct GBASerializedState* state) {
302 memcpy(state->vram, video->vram, SIZE_VRAM);
303 memcpy(state->oam, video->oam.raw, SIZE_OAM);
304 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
305 STORE_32(video->event.when - mTimingCurrentTime(&video->p->timing), 0, &state->video.nextEvent);
306 STORE_32(video->frameCounter, 0, &state->video.frameCounter);
307}
308
309void GBAVideoDeserialize(struct GBAVideo* video, const struct GBASerializedState* state) {
310 memcpy(video->vram, state->vram, SIZE_VRAM);
311 uint16_t value;
312 int i;
313 for (i = 0; i < SIZE_OAM; i += 2) {
314 LOAD_16(value, i, state->oam);
315 GBAStore16(video->p->cpu, BASE_OAM | i, value, 0);
316 }
317 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
318 LOAD_16(value, i, state->pram);
319 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, value, 0);
320 }
321 LOAD_32(video->frameCounter, 0, &state->video.frameCounter);
322
323 uint32_t when;
324 LOAD_32(when, 0, &state->video.nextEvent);
325 GBARegisterDISPSTAT dispstat = state->io[REG_DISPSTAT >> 1];
326 if (GBARegisterDISPSTATIsInHblank(dispstat)) {
327 video->event.callback = _startHdraw;
328 } else {
329 video->event.callback = _startHblank;
330 }
331 mTimingSchedule(&video->p->timing, &video->event, when);
332
333 LOAD_16(video->vcount, REG_VCOUNT, state->io);
334 video->renderer->reset(video->renderer);
335}