src/gba/gba-video.c (view raw)
1#include "gba-video.h"
2
3#include "gba.h"
4#include "gba-io.h"
5#include "gba-rr.h"
6#include "gba-serialize.h"
7#include "gba-thread.h"
8
9#include "util/memory.h"
10
11static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer);
12static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer);
13static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer);
14static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
15static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value);
16static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam);
17static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y);
18static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer);
19
20static struct GBAVideoRenderer dummyRenderer = {
21 .init = GBAVideoDummyRendererInit,
22 .reset = GBAVideoDummyRendererReset,
23 .deinit = GBAVideoDummyRendererDeinit,
24 .writeVideoRegister = GBAVideoDummyRendererWriteVideoRegister,
25 .writePalette = GBAVideoDummyRendererWritePalette,
26 .writeOAM = GBAVideoDummyRendererWriteOAM,
27 .drawScanline = GBAVideoDummyRendererDrawScanline,
28 .finishFrame = GBAVideoDummyRendererFinishFrame
29};
30
31void GBAVideoInit(struct GBAVideo* video) {
32 video->renderer = &dummyRenderer;
33 video->vram = 0;
34}
35
36void GBAVideoReset(struct GBAVideo* video) {
37 video->inHblank = 0;
38 video->inVblank = 0;
39 video->vcounter = 0;
40 video->vblankIRQ = 0;
41 video->hblankIRQ = 0;
42 video->vcounterIRQ = 0;
43 video->vcountSetting = 0;
44
45 video->vcount = 0;
46
47 video->lastHblank = 0;
48 video->nextHblank = VIDEO_HDRAW_LENGTH;
49 video->nextEvent = video->nextHblank;
50 video->eventDiff = video->nextEvent;
51
52 video->nextHblankIRQ = 0;
53 video->nextVblankIRQ = 0;
54 video->nextVcounterIRQ = 0;
55
56 if (video->vram) {
57 mappedMemoryFree(video->vram, SIZE_VRAM);
58 }
59 video->vram = anonymousMemoryMap(SIZE_VRAM);
60 video->renderer->vram = video->vram;
61
62 int i;
63 for (i = 0; i < 128; ++i) {
64 video->oam.raw[i * 4] = 0x0200;
65 video->oam.raw[i * 4 + 1] = 0x0000;
66 video->oam.raw[i * 4 + 2] = 0x0000;
67 video->oam.raw[i * 4 + 3] = 0x0000;
68 }
69}
70
71void GBAVideoDeinit(struct GBAVideo* video) {
72 GBAVideoAssociateRenderer(video, &dummyRenderer);
73 mappedMemoryFree(video->vram, SIZE_VRAM);
74}
75
76void GBAVideoAssociateRenderer(struct GBAVideo* video, struct GBAVideoRenderer* renderer) {
77 video->renderer->deinit(video->renderer);
78 video->renderer = renderer;
79 renderer->palette = video->palette;
80 renderer->vram = video->vram;
81 renderer->oam = &video->oam;
82 video->renderer->init(video->renderer);
83}
84
85int32_t GBAVideoProcessEvents(struct GBAVideo* video, int32_t cycles) {
86 video->nextEvent -= cycles;
87 video->eventDiff += cycles;
88 if (video->nextEvent <= 0) {
89 int32_t lastEvent = video->nextEvent;
90 video->lastHblank -= video->eventDiff;
91 video->nextHblank -= video->eventDiff;
92 video->nextHblankIRQ -= video->eventDiff;
93 video->nextVcounterIRQ -= video->eventDiff;
94
95 if (video->inHblank) {
96 // End Hblank
97 video->inHblank = 0;
98 video->nextEvent = video->nextHblank;
99
100 ++video->vcount;
101 video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
102
103 switch (video->vcount) {
104 case VIDEO_VERTICAL_PIXELS:
105 video->inVblank = 1;
106 if (GBASyncDrawingFrame(video->p->sync)) {
107 video->renderer->finishFrame(video->renderer);
108 }
109 video->nextVblankIRQ = video->nextEvent + VIDEO_TOTAL_LENGTH;
110 GBAMemoryRunVblankDMAs(video->p, lastEvent);
111 if (video->vblankIRQ) {
112 GBARaiseIRQ(video->p, IRQ_VBLANK);
113 }
114 GBASyncPostFrame(video->p->sync);
115 break;
116 case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
117 if (video->p->rr) {
118 GBARRNextFrame(video->p->rr);
119 }
120 video->inVblank = 0;
121 break;
122 case VIDEO_VERTICAL_TOTAL_PIXELS:
123 video->vcount = 0;
124 video->p->memory.io[REG_VCOUNT >> 1] = 0;
125 break;
126 }
127
128 video->vcounter = video->vcount == video->vcountSetting;
129 if (video->vcounter && video->vcounterIRQ) {
130 GBARaiseIRQ(video->p, IRQ_VCOUNTER);
131 video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
132 }
133 } else {
134 // Begin Hblank
135 video->inHblank = 1;
136 video->lastHblank = video->nextHblank;
137 video->nextEvent = video->lastHblank + VIDEO_HBLANK_LENGTH;
138 video->nextHblank = video->nextEvent + VIDEO_HDRAW_LENGTH;
139 video->nextHblankIRQ = video->nextHblank;
140
141 if (video->vcount < VIDEO_VERTICAL_PIXELS && GBASyncDrawingFrame(video->p->sync)) {
142 video->renderer->drawScanline(video->renderer, video->vcount);
143 }
144
145 if (video->vcount < VIDEO_VERTICAL_PIXELS) {
146 GBAMemoryRunHblankDMAs(video->p, lastEvent);
147 }
148 if (video->hblankIRQ) {
149 GBARaiseIRQ(video->p, IRQ_HBLANK);
150 }
151 }
152
153 video->eventDiff = 0;
154 }
155 video->p->memory.io[REG_DISPSTAT >> 1] &= 0xFFF8;
156 video->p->memory.io[REG_DISPSTAT >> 1] |= (video->inVblank) | (video->inHblank << 1) | (video->vcounter << 2);
157 return video->nextEvent;
158}
159
160void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
161 union GBARegisterDISPSTAT dispstat;
162 dispstat.packed = value;
163 video->vblankIRQ = dispstat.vblankIRQ;
164 video->hblankIRQ = dispstat.hblankIRQ;
165 video->vcounterIRQ = dispstat.vcounterIRQ;
166 video->vcountSetting = dispstat.vcountSetting;
167
168 if (video->vcounterIRQ) {
169 // FIXME: this can be too late if we're in the middle of an Hblank
170 video->nextVcounterIRQ = video->nextHblank + VIDEO_HBLANK_LENGTH + (video->vcountSetting - video->vcount) * VIDEO_HORIZONTAL_LENGTH;
171 if (video->nextVcounterIRQ < video->nextEvent) {
172 video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
173 }
174 }
175}
176
177static void GBAVideoDummyRendererInit(struct GBAVideoRenderer* renderer) {
178 UNUSED(renderer);
179 // Nothing to do
180}
181
182static void GBAVideoDummyRendererReset(struct GBAVideoRenderer* renderer) {
183 UNUSED(renderer);
184 // Nothing to do
185}
186
187static void GBAVideoDummyRendererDeinit(struct GBAVideoRenderer* renderer) {
188 UNUSED(renderer);
189 // Nothing to do
190}
191
192static uint16_t GBAVideoDummyRendererWriteVideoRegister(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
193 UNUSED(renderer);
194 UNUSED(address);
195 return value;
196}
197
198static void GBAVideoDummyRendererWritePalette(struct GBAVideoRenderer* renderer, uint32_t address, uint16_t value) {
199 UNUSED(renderer);
200 UNUSED(address);
201 UNUSED(value);
202 // Nothing to do
203}
204
205static void GBAVideoDummyRendererWriteOAM(struct GBAVideoRenderer* renderer, uint32_t oam) {
206 UNUSED(renderer);
207 UNUSED(oam);
208 // Nothing to do
209}
210
211static void GBAVideoDummyRendererDrawScanline(struct GBAVideoRenderer* renderer, int y) {
212 UNUSED(renderer);
213 UNUSED(y);
214 // Nothing to do
215}
216
217static void GBAVideoDummyRendererFinishFrame(struct GBAVideoRenderer* renderer) {
218 UNUSED(renderer);
219 // Nothing to do
220}
221
222void GBAVideoSerialize(struct GBAVideo* video, struct GBASerializedState* state) {
223 memcpy(state->vram, video->renderer->vram, SIZE_VRAM);
224 memcpy(state->oam, video->oam.raw, SIZE_OAM);
225 memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
226 union GBARegisterDISPSTAT dispstat;
227 dispstat.inVblank = video->inVblank;
228 dispstat.inHblank = video->inHblank;
229 dispstat.vcounter = video->vcounter;
230 dispstat.vblankIRQ = video->vblankIRQ;
231 dispstat.hblankIRQ = video->hblankIRQ;
232 dispstat.vcounterIRQ = video->vcounterIRQ;
233 dispstat.vcountSetting = video->vcountSetting;
234 state->io[REG_DISPSTAT >> 1] = dispstat.packed;
235 state->video.nextEvent = video->nextEvent;
236 state->video.eventDiff = video->eventDiff;
237 state->video.lastHblank = video->lastHblank;
238 state->video.nextHblank = video->nextHblank;
239 state->video.nextHblankIRQ = video->nextHblankIRQ;
240 state->video.nextVblankIRQ = video->nextVblankIRQ;
241 state->video.nextVcounterIRQ = video->nextVcounterIRQ;
242}
243
244void GBAVideoDeserialize(struct GBAVideo* video, struct GBASerializedState* state) {
245 memcpy(video->renderer->vram, state->vram, SIZE_VRAM);
246 int i;
247 for (i = 0; i < SIZE_OAM; i += 2) {
248 GBAStore16(video->p->cpu, BASE_OAM | i, state->oam[i >> 1], 0);
249 }
250 for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
251 GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, state->pram[i >> 1], 0);
252 }
253 union GBARegisterDISPSTAT dispstat;
254 dispstat.packed = state->io[REG_DISPSTAT >> 1];
255 video->inVblank = dispstat.inVblank;
256 video->inHblank = dispstat.inHblank;
257 video->vcounter = dispstat.vcounter;
258 video->vblankIRQ = dispstat.vblankIRQ;
259 video->hblankIRQ = dispstat.hblankIRQ;
260 video->vcounterIRQ = dispstat.vcounterIRQ;
261 video->vcountSetting = dispstat.vcountSetting;
262 video->nextEvent = state->video.nextEvent;
263 video->eventDiff = state->video.eventDiff;
264 video->lastHblank = state->video.lastHblank;
265 video->nextHblank = state->video.nextHblank;
266 video->nextHblankIRQ = state->video.nextHblankIRQ;
267 video->nextVblankIRQ = state->video.nextVblankIRQ;
268 video->nextVcounterIRQ = state->video.nextVcounterIRQ;
269 video->vcount = state->io[REG_VCOUNT >> 1];
270}