all repos — mgba @ 19758d711528b15a255b353d1ef740d516b8685e

mGBA Game Boy Advance Emulator

GBA Video: Refactor video routines to be in a more consistent state during callbacks
Jeffrey Pfau jeffrey@endrift.com
Sat, 24 Jan 2015 01:02:09 -0800
commit

19758d711528b15a255b353d1ef740d516b8685e

parent

a7357df857cf775d339fbc24fd56de3f1be4fba2

6 files changed, 78 insertions(+), 59 deletions(-)

jump to
M src/gba/gba-cli.c → src/gba/gba-cli.c 
@@ -66,12 +66,12 @@ static bool _GBACLIDebuggerCustom(struct CLIDebuggerSystem* debugger) {
 	struct GBACLIDebugger* gbaDebugger = (struct GBACLIDebugger*) debugger;
 
 	if (gbaDebugger->frameAdvance) {
-		if (!gbaDebugger->inVblank && GBARegisterDISPSTATIsInVblank(gbaDebugger->context->gba->video.dispstat)) {
+		if (!gbaDebugger->inVblank && GBARegisterDISPSTATIsInVblank(gbaDebugger->context->gba->memory.io[REG_DISPSTAT >> 1])) {
 			ARMDebuggerEnter(&gbaDebugger->d.p->d, DEBUGGER_ENTER_BREAKPOINT);
 			gbaDebugger->frameAdvance = false;
 			return false;
 		}
-		gbaDebugger->inVblank = GBARegisterDISPSTATGetInVblank(gbaDebugger->context->gba->video.dispstat);
+		gbaDebugger->inVblank = GBARegisterDISPSTATGetInVblank(gbaDebugger->context->gba->memory.io[REG_DISPSTAT >> 1]);
 		return true;
 	}
 	return false;

@@ -96,7 +96,7 @@ debugger->d.state = DEBUGGER_CUSTOM;
 
 	struct GBACLIDebugger* gbaDebugger = (struct GBACLIDebugger*) debugger->system;
 	gbaDebugger->frameAdvance = true;
-	gbaDebugger->inVblank = GBARegisterDISPSTATGetInVblank(gbaDebugger->context->gba->video.dispstat);
+	gbaDebugger->inVblank = GBARegisterDISPSTATGetInVblank(gbaDebugger->context->gba->memory.io[REG_DISPSTAT >> 1]);
 }
 
 static void _load(struct CLIDebugger* debugger, struct CLIDebugVector* dv) {
M src/gba/gba-thread.c → src/gba/gba-thread.c 
@@ -616,25 +616,6 @@ }
 		} while (sync->videoFrameWait && sync->videoFramePending);
 	}
 	MutexUnlock(&sync->videoFrameMutex);
-
-	struct GBAThread* thread = GBAThreadGetContext();
-	if (!thread) {
-		return;
-	}
-
-	if (thread->rewindBuffer) {
-		--thread->rewindBufferNext;
-		if (thread->rewindBufferNext <= 0) {
-			thread->rewindBufferNext = thread->rewindBufferInterval;
-			GBARecordFrame(thread);
-		}
-	}
-	if (thread->stream) {
-		thread->stream->postVideoFrame(thread->stream, thread->renderer);
-	}
-	if (thread->frameCallback) {
-		thread->frameCallback(thread);
-	}
 }
 
 bool GBASyncWaitFrameStart(struct GBASync* sync, int frameskip) {
M src/gba/gba-video.c → src/gba/gba-video.c 
@@ -41,7 +41,6 @@ video->vram = 0;
 }
 
 void GBAVideoReset(struct GBAVideo* video) {
-	video->dispstat = 0;
 	video->vcount = VIDEO_VERTICAL_TOTAL_PIXELS - 1;
 
 	video->lastHblank = 0;

@@ -96,53 +95,57 @@ video->lastHblank -= video->eventDiff;
 		video->nextHblank -= video->eventDiff;
 		video->nextHblankIRQ -= video->eventDiff;
 		video->nextVcounterIRQ -= video->eventDiff;
+		video->eventDiff = 0;
+		uint16_t dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
 
-		if (GBARegisterDISPSTATIsInHblank(video->dispstat)) {
+		if (GBARegisterDISPSTATIsInHblank(dispstat)) {
 			// End Hblank
-			video->dispstat = GBARegisterDISPSTATClearInHblank(video->dispstat);
+			dispstat = GBARegisterDISPSTATClearInHblank(dispstat);
 			video->nextEvent = video->nextHblank;
 
 			++video->vcount;
+			if (video->vcount == VIDEO_VERTICAL_TOTAL_PIXELS) {
+				video->vcount = 0;
+			}
 			video->p->memory.io[REG_VCOUNT >> 1] = video->vcount;
 
+			if (video->vcount == GBARegisterDISPSTATGetVcountSetting(dispstat)) {
+				dispstat = GBARegisterDISPSTATFillVcounter(dispstat);
+				if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
+					GBARaiseIRQ(video->p, IRQ_VCOUNTER);
+					video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
+				}
+			} else {
+				dispstat = GBARegisterDISPSTATClearVcounter(dispstat);
+			}
+			video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
+
+			// Note: state may be recorded during callbacks, so ensure it is consistent!
 			switch (video->vcount) {
+			case 0:
+				GBAFrameStarted(video->p);
+				break;
 			case VIDEO_VERTICAL_PIXELS:
-				video->dispstat = GBARegisterDISPSTATFillInVblank(video->dispstat);
+				video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATFillInVblank(dispstat);
 				if (GBASyncDrawingFrame(video->p->sync)) {
 					video->renderer->finishFrame(video->renderer);
 				}
 				video->nextVblankIRQ = video->nextEvent + VIDEO_TOTAL_LENGTH;
 				GBAMemoryRunVblankDMAs(video->p, lastEvent);
-				if (GBARegisterDISPSTATIsVblankIRQ(video->dispstat)) {
+				if (GBARegisterDISPSTATIsVblankIRQ(dispstat)) {
 					GBARaiseIRQ(video->p, IRQ_VBLANK);
 				}
+				GBAFrameEnded(video->p);
 				GBASyncPostFrame(video->p->sync);
 				++video->frameCounter;
 				break;
 			case VIDEO_VERTICAL_TOTAL_PIXELS - 1:
-				if (video->p->rr) {
-					GBARRNextFrame(video->p->rr);
-				}
-				video->dispstat = GBARegisterDISPSTATClearInVblank(video->dispstat);
-				break;
-			case VIDEO_VERTICAL_TOTAL_PIXELS:
-				video->vcount = 0;
-				video->p->memory.io[REG_VCOUNT >> 1] = 0;
+				video->p->memory.io[REG_DISPSTAT >> 1] = GBARegisterDISPSTATClearInVblank(dispstat);
 				break;
 			}
-
-			if (video->vcount == GBARegisterDISPSTATGetVcountSetting(video->dispstat)) {
-				video->dispstat = GBARegisterDISPSTATFillVcounter(video->dispstat);
-				if (GBARegisterDISPSTATIsVcounterIRQ(video->dispstat)) {
-					GBARaiseIRQ(video->p, IRQ_VCOUNTER);
-					video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
-				}
-			} else {
-				video->dispstat = GBARegisterDISPSTATClearVcounter(video->dispstat);
-			}
 		} else {
 			// Begin Hblank
-			video->dispstat = GBARegisterDISPSTATFillInHblank(video->dispstat);
+			dispstat = GBARegisterDISPSTATFillInHblank(dispstat);
 			video->lastHblank = video->nextHblank;
 			video->nextEvent = video->lastHblank + VIDEO_HBLANK_LENGTH;
 			video->nextHblank = video->nextEvent + VIDEO_HDRAW_LENGTH;

@@ -155,25 +158,24 @@
 			if (video->vcount < VIDEO_VERTICAL_PIXELS) {
 				GBAMemoryRunHblankDMAs(video->p, lastEvent);
 			}
-			if (GBARegisterDISPSTATIsHblankIRQ(video->dispstat)) {
+			if (GBARegisterDISPSTATIsHblankIRQ(dispstat)) {
 				GBARaiseIRQ(video->p, IRQ_HBLANK);
 			}
+			video->p->memory.io[REG_DISPSTAT >> 1] = dispstat;
 		}
-
-		video->eventDiff = 0;
 	}
-	video->p->memory.io[REG_DISPSTAT >> 1] &= 0xFFF8;
-	video->p->memory.io[REG_DISPSTAT >> 1] |= video->dispstat & 0x7;
 	return video->nextEvent;
 }
 
 void GBAVideoWriteDISPSTAT(struct GBAVideo* video, uint16_t value) {
-	video->dispstat &= 0x7;
-	video->dispstat |= value & 0xFFF8;
+	video->p->memory.io[REG_DISPSTAT >> 1] &= 0x7;
+	video->p->memory.io[REG_DISPSTAT >> 1] |= value & 0xFFF8;
+
+	uint16_t dispstat = video->p->memory.io[REG_DISPSTAT >> 1];
 
-	if (GBARegisterDISPSTATIsVcounterIRQ(video->dispstat)) {
+	if (GBARegisterDISPSTATIsVcounterIRQ(dispstat)) {
 		// FIXME: this can be too late if we're in the middle of an Hblank
-		video->nextVcounterIRQ = video->nextHblank + VIDEO_HBLANK_LENGTH + (GBARegisterDISPSTATGetVcountSetting(video->dispstat) - video->vcount) * VIDEO_HORIZONTAL_LENGTH;
+		video->nextVcounterIRQ = video->nextHblank + VIDEO_HBLANK_LENGTH + (GBARegisterDISPSTATGetVcountSetting(dispstat) - video->vcount) * VIDEO_HORIZONTAL_LENGTH;
 		if (video->nextVcounterIRQ < video->nextEvent) {
 			video->nextVcounterIRQ += VIDEO_TOTAL_LENGTH;
 		}

@@ -237,7 +239,6 @@ void GBAVideoSerialize(struct GBAVideo* video, struct GBASerializedState* state) {
 	memcpy(state->vram, video->renderer->vram, SIZE_VRAM);
 	memcpy(state->oam, video->oam.raw, SIZE_OAM);
 	memcpy(state->pram, video->palette, SIZE_PALETTE_RAM);
-	state->io[REG_DISPSTAT >> 1] = video->dispstat;
 	state->video.nextEvent = video->nextEvent;
 	state->video.eventDiff = video->eventDiff;
 	state->video.lastHblank = video->lastHblank;

@@ -257,7 +258,6 @@ }
 	for (i = 0; i < SIZE_PALETTE_RAM; i += 2) {
 		GBAStore16(video->p->cpu, BASE_PALETTE_RAM | i, state->pram[i >> 1], 0);
 	}
-	video->dispstat = state->io[REG_DISPSTAT >> 1];
 	video->nextEvent = state->video.nextEvent;
 	video->eventDiff = state->video.eventDiff;
 	video->lastHblank = state->video.lastHblank;
M src/gba/gba-video.h → src/gba/gba-video.h 
@@ -173,8 +173,6 @@ struct GBAVideo {
 	struct GBA* p;
 	struct GBAVideoRenderer* renderer;
 
-	GBARegisterDISPSTAT dispstat;
-
 	// VCOUNT
 	int vcount;
M src/gba/gba.c → src/gba/gba.c 
@@ -8,6 +8,7 @@
 #include "gba-bios.h"
 #include "gba-io.h"
 #include "gba-rr.h"
+#include "gba-serialize.h"
 #include "gba-sio.h"
 #include "gba-thread.h"
 

@@ -634,3 +635,39 @@ if (gba->debugger) {
 		ARMDebuggerEnter(gba->debugger, DEBUGGER_ENTER_ILLEGAL_OP);
 	}
 }
+
+void GBAFrameStarted(struct GBA* gba) {
+	UNUSED(gba);
+
+	struct GBAThread* thread = GBAThreadGetContext();
+	if (!thread) {
+		return;
+	}
+
+	if (thread->rewindBuffer) {
+		--thread->rewindBufferNext;
+		if (thread->rewindBufferNext <= 0) {
+			thread->rewindBufferNext = thread->rewindBufferInterval;
+			GBARecordFrame(thread);
+		}
+	}
+}
+
+void GBAFrameEnded(struct GBA* gba) {
+	if (gba->rr) {
+		GBARRNextFrame(gba->rr);
+	}
+
+	struct GBAThread* thread = GBAThreadGetContext();
+	if (!thread) {
+		return;
+	}
+
+	if (thread->stream) {
+		thread->stream->postVideoFrame(thread->stream, thread->renderer);
+	}
+
+	if (thread->frameCallback) {
+		thread->frameCallback(thread);
+	}
+}
M src/gba/gba.h → src/gba/gba.h 
@@ -181,6 +181,9 @@ bool GBAIsBIOS(struct VFile* vf);
 void GBAGetGameCode(struct GBA* gba, char* out);
 void GBAGetGameTitle(struct GBA* gba, char* out);
 
+void GBAFrameStarted(struct GBA* gba);
+void GBAFrameEnded(struct GBA* gba);
+
 __attribute__((format (printf, 3, 4)))
 void GBALog(struct GBA* gba, enum GBALogLevel level, const char* format, ...);