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 "video.h"
7
8#include "core/sync.h"
9#include "gba/gba.h"
10#include "gba/io.h"
11#include "gba/rr/rr.h"
12#include "gba/serialize.h"
13
14#include "util/memory.h"
15
16mLOG_DEFINE_CATEGORY(GBA_VIDEO, "GBA Video");
17
18static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer);
19static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer);
20static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer);
21static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
22static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address);
23static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
24static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam);
25static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y);
26static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer);
27static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, unsigned* stride, const void** pixels);
28
29const int GBAVideoObjSizes[16][2] = {
30 { 8, 8 },
31 { 16, 16 },
32 { 32, 32 },
33 { 64, 64 },
34 { 16, 8 },
35 { 32, 8 },
36 { 32, 16 },
37 { 64, 32 },
38 { 8, 16 },
39 { 8, 32 },
40 { 16, 32 },
41 { 32, 64 },
42 { 0, 0 },
43 { 0, 0 },
44 { 0, 0 },
45 { 0, 0 },
46};
47
48static struct GBAVideoRenderer dummyRenderer = {
49 .init = GBAVideoDummyRendererInit,
50 .reset = GBAVideoDummyRendererReset,
51 .deinit = GBAVideoDummyRendererDeinit,
52 .writeVideoRegister = GBAVideoDummyRendererWriteVideoRegister,
53 .writeVRAM = GBAVideoDummyRendererWriteVRAM,
54 .writePalette = GBAVideoDummyRendererWritePalette,
55 .writeOAM = GBAVideoDummyRendererWriteOAM,
56 .drawScanline = GBAVideoDummyRendererDrawScanline,
57 .finishFrame = GBAVideoDummyRendererFinishFrame,
58 .getPixels = GBAVideoDummyRendererGetPixels
59};
60
61void GBAVideoInit(struct GBAVideo* video) {
62 video->renderer = &dummyRenderer;
63 video->vram = 0;
64 video->frameskip = 0;
65}
66
67void GBAVideoReset(struct GBAVideo* video) {
68 if (video->p->memory.fullBios) {
69 video->vcount = 0;
70 } else {
71 // TODO: Verify exact scanline hardware
72 video->vcount = 0x7E;
73 }
74 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
75
76 video->nextHblank = VIDEO_HDRAW_LENGTH;
77 video->nextEvent = video->nextHblank;
78 video->eventDiff = 0;
79
80 video->nextHblankIRQ = 0;
81 video->nextVblankIRQ = 0;
82 video->nextVcounterIRQ = 0;
83
84 video->frameCounter = 0;
85 video->frameskipCounter = 0;
86
87 if (video->vram) {
88 mappedMemoryFree(video->vram, SIZE_VRAM);
89 }
90 video->vram = anonymousMemoryMap(SIZE_VRAM);
91 video->renderer->vram = video->vram;
92
93 memset(video->palette, 0, sizeof(video->palette));
94 memset(video->oam.raw, 0, sizeof(video->oam.raw));
95
96 video->renderer->deinit(video->renderer);
97 video->renderer->init(video->renderer);
98}
99
100void GBAVideoDeinit(struct GBAVideo* video) {
101 GBAVideoAssociateRenderer(video, &dummyRenderer);
102 mappedMemoryFree(video->vram, SIZE_VRAM);
103}
104
105void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
106 video->renderer->deinit(video->renderer);
107 video->renderer = renderer;
108 renderer->palette = video->palette;
109 renderer->vram = video->vram;
110 renderer->oam = &video->oam;
111 video->renderer->init(video->renderer);
112}
113
114int32_t GBAVideoProcessEvents(struct GBAVideo* video, int32_t cycles) {
115 video->nextEvent -= cycles;
116 video->eventDiff += cycles;
117 if (video->nextEvent <= 0) {
118 int32_t lastEvent = video->nextEvent;
119 video->nextHblank -= video->eventDiff;
120 video->nextHblankIRQ -= video->eventDiff;
121 video->nextVcounterIRQ -= video->eventDiff;
122 video->eventDiff = 0;
123 uint16_t dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
124
125 if (GBARegisterDISPSTATIsInHblank(dispstat)) {
126 // End Hblank
127 dispstat = GBARegisterDISPSTATClearInHblank(dispstat);
128 video->nextEvent = video->nextHblank;
129
130 ++video->vcount;
131 if (video->vcount == VIDEO_VERTICAL_TOTAL_PIXELS) {
132 video->vcount = 0;
133 }
134 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
135
136 if (video->vcount == GBARegisterDISPSTATGetVcountSetting(dispstat)) {
137 dispstat = GBARegisterDISPSTATFillVcounter(dispstat);
138 if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
139 GBARaiseIRQ(video->p, IRQ_VCOUNTER);
140 video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
141 }
142 } else {
143 dispstat = GBARegisterDISPSTATClearVcounter(dispstat);
144 }
145 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
146
147 // Note: state may be recorded during callbacks, so ensure it is consistent!
148 switch (video->vcount) {
149 case 0:
150 GBAFrameStarted(video->p);
151 break;
152 case VIDEO_VERTICAL_PIXELS:
153 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATFillInVblank(dispstat);
154 if (video->frameskipCounter <= 0) {
155 video->renderer->finishFrame(video->renderer);
156 }
157 video->nextVblankIRQ = video->nextEvent + VIDEO_TOTAL_LENGTH;
158 GBAMemoryRunVblankDMAs(video->p, lastEvent);
159 if (GBARegisterDISPSTATIsVblankIRQ(dispstat)) {
160 GBARaiseIRQ(video->p, IRQ_VBLANK);
161 }
162 GBAFrameEnded(video->p);
163 --video->frameskipCounter;
164 if (video->frameskipCounter < 0) {
165 mCoreSyncPostFrame(video->p->sync);
166 video->frameskipCounter = video->frameskip;
167 }
168 ++video->frameCounter;
169 break;
170 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
171 video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATClearInVblank(dispstat);
172 break;
173 }
174 } else {
175 // Begin Hblank
176 dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
177 video->nextEvent = video->nextHblank + VIDEO_HBLANK_LENGTH;
178 video->nextHblank = video->nextEvent + VIDEO_HDRAW_LENGTH;
179 video->nextHblankIRQ = video->nextHblank;
180
181 if (video->vcount < VIDEO_VERTICAL_PIXELS && video->frameskipCounter <= 0) {
182 video->renderer->drawScanline(video->renderer, video->vcount);
183 }
184
185 if (video->vcount < VIDEO_VERTICAL_PIXELS) {
186 GBAMemoryRunHblankDMAs(video->p, lastEvent);
187 }
188 if (GBARegisterDISPSTATIsHblankIRQ(dispstat)) {
189 GBARaiseIRQ(video->p, IRQ_HBLANK);
190 }
191 video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
192 }
193 }
194 return video->nextEvent;
195}
196
197void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
198 video->p->memory.io[REG_DISPSTAT >> 1] &= 0x7;
199 video->p->memory.io[REG_DISPSTAT >> 1] |= value;
200
201 uint16_t dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
202
203 if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
204 // FIXME: this can be too late if we're in the middle of an Hblank
205 video->nextVcounterIRQ = video->nextHblank + VIDEO_HBLANK_LENGTH + (GBARegisterDISPSTATGetVcountSetting(dispstat) - video->vcount) * VIDEO_HORIZONTAL_LENGTH;
206 if (video->nextVcounterIRQ < video->nextEvent) {
207 video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
208 }
209 }
210}
211
212static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
213 UNUSED(renderer);
214 // Nothing to do
215}
216
217static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
218 UNUSED(renderer);
219 // Nothing to do
220}
221
222static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
223 UNUSED(renderer);
224 // Nothing to do
225}
226
227static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
228 UNUSED(renderer);
229 UNUSED(address);
230 return value;
231}
232
233static void GBAVideoDummyRendererWriteVRAM(struct GBAVideoRenderer* renderer, uint32_t address) {
234 UNUSED(renderer);
235 UNUSED(address);
236 // Nothing to do
237}
238
239static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
240 UNUSED(renderer);
241 UNUSED(address);
242 UNUSED(value);
243 // Nothing to do
244}
245
246static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
247 UNUSED(renderer);
248 UNUSED(oam);
249 // Nothing to do
250}
251
252static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
253 UNUSED(renderer);
254 UNUSED(y);
255 // Nothing to do
256}
257
258static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
259 UNUSED(renderer);
260 // Nothing to do
261}
262
263static void GBAVideoDummyRendererGetPixels(struct GBAVideoRenderer* renderer, unsigned* stride, const void** pixels) {
264 UNUSED(renderer);
265 UNUSED(stride);
266 UNUSED(pixels);
267 // Nothing to do
268}
269
270void GBAVideoSerialize(const struct GBAVideo* video, struct GBASerializedState* state) {
271 memcpy(state->vram, video->renderer->vram, SIZE_VRAM);
272 memcpy(state->oam, video->oam.raw, SIZE_OAM);
273 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
274 STORE_32(video->nextEvent, 0, &state->video.nextEvent);
275 STORE_32(video->eventDiff, 0, &state->video.eventDiff);
276 STORE_32(video->nextHblank, 0, &state->video.nextHblank);
277 STORE_32(video->nextHblankIRQ, 0, &state->video.nextHblankIRQ);
278 STORE_32(video->nextVblankIRQ, 0, &state->video.nextVblankIRQ);
279 STORE_32(video->nextVcounterIRQ, 0, &state->video.nextVcounterIRQ);
280 STORE_32(video->frameCounter, 0, &state->video.frameCounter);
281}
282
283void GBAVideoDeserialize(struct GBAVideo* video, const struct GBASerializedState* state) {
284 memcpy(video->renderer->vram, state->vram, SIZE_VRAM);
285 uint16_t value;
286 int i;
287 for (i = 0; i < SIZE_OAM; i += 2) {
288 LOAD_16(value, i, state->oam);
289 GBAStore16(video->p->cpu, BASE_OAM | i, value, 0);
290 }
291 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
292 LOAD_16(value, i, state->pram);
293 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, value, 0);
294 }
295 LOAD_32(video->nextEvent, 0, &state->video.nextEvent);
296 LOAD_32(video->eventDiff, 0, &state->video.eventDiff);
297 LOAD_32(video->nextHblank, 0, &state->video.nextHblank);
298 LOAD_32(video->nextHblankIRQ, 0, &state->video.nextHblankIRQ);
299 LOAD_32(video->nextVblankIRQ, 0, &state->video.nextVblankIRQ);
300 LOAD_32(video->nextVcounterIRQ, 0, &state->video.nextVcounterIRQ);
301 LOAD_32(video->frameCounter, 0, &state->video.frameCounter);
302 LOAD_16(video->vcount, REG_VCOUNT, state->io);
303}