GBA: Ability to boot directly into the BIOS

CHANGES

@@ -20,6 +20,7 @@ Features:
  - Ability to cap fast forward speed
  - Finer control over FPS target
  - Holdable shortcut for rewinding one frame at a time
+ - Ability to boot directly into the BIOS
 Bugfixes:
  - ARM7: Fix SWI and IRQ timings
  - GBA Audio: Force audio FIFOs to 32-bit

src/gba/gba.c

@@ -633,10 +633,18 @@ bool GBAIsBIOS(struct VFile* vf) {
 }
 
 void GBAGetGameCode(struct GBA* gba, char* out) {
+	if (!gba->memory.rom) {
+		out[0] = '\0';
+		return;
+	}
 	memcpy(out, &((struct GBACartridge*) gba->memory.rom)->id, 4);
 }
 
 void GBAGetGameTitle(struct GBA* gba, char* out) {
+	if (!gba->memory.rom) {
+		strncpy(out, "(BIOS)", 12);
+		return;
+	}
 	memcpy(out, &((struct GBACartridge*) gba->memory.rom)->title, 12);
 }
 

src/gba/memory.c

@@ -47,6 +47,7 @@ void GBAMemoryInit(struct GBA* gba) {
 	gba->memory.wram = 0;
 	gba->memory.iwram = 0;
 	gba->memory.rom = 0;
+	gba->memory.romSize = 0;
 	gba->memory.hw.p = gba;
 
 	int i;

src/gba/serialize.c

@@ -29,8 +29,13 @@ void GBASerialize(struct GBA* gba, struct GBASerializedState* state) {
 	state->biosChecksum = gba->biosChecksum;
 	state->romCrc32 = gba->romCrc32;
 
-	state->id = ((struct GBACartridge*) gba->memory.rom)->id;
-	memcpy(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title));
+	if (gba->memory.rom) {
+		state->id = ((struct GBACartridge*) gba->memory.rom)->id;
+		memcpy(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title));
+	} else {
+		state->id = 0;
+		memset(state->title, 0, sizeof(state->title));
+	}
 
 	memcpy(state->cpu.gprs, gba->cpu->gprs, sizeof(state->cpu.gprs));
 	state->cpu.cpsr = gba->cpu->cpsr;
@@ -67,9 +72,12 @@ void GBADeserialize(struct GBA* gba, const struct GBASerializedState* state) {
 			return;
 		}
 	}
-	if (state->id != ((struct GBACartridge*) gba->memory.rom)->id || memcmp(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title))) {
+	if (gba->memory.rom && state->id != ((struct GBACartridge*) gba->memory.rom)->id || memcmp(state->title, ((struct GBACartridge*) gba->memory.rom)->title, sizeof(state->title))) {
 		GBALog(gba, GBA_LOG_WARN, "Savestate is for a different game");
 		return;
+	} else if (!gba->memory.rom && state->id != 0) {
+		GBALog(gba, GBA_LOG_WARN, "Savestate is for a game, but no game loaded");
+		return;
 	}
 	if (state->romCrc32 != gba->romCrc32) {
 		GBALog(gba, GBA_LOG_WARN, "Savestate is for a different version of the game");

src/gba/supervisor/thread.c

@@ -167,15 +167,15 @@ static THREAD_ENTRY _GBAThreadRun(void* context) {
 			GBAOverrideApply(&gba, &threadContext->override);
 		}
 
-		if (threadContext->bios && GBAIsBIOS(threadContext->bios)) {
-			GBALoadBIOS(&gba, threadContext->bios);
-		}
-
 		if (threadContext->patch && loadPatch(threadContext->patch, &patch)) {
 			GBAApplyPatch(&gba, &patch);
 		}
 	}
 
+	if (threadContext->bios && GBAIsBIOS(threadContext->bios)) {
+		GBALoadBIOS(&gba, threadContext->bios);
+	}
+
 	if (threadContext->movie) {
 		struct VDir* movieDir = VDirOpen(threadContext->movie);
 #ifdef USE_LIBZIP
@@ -400,7 +400,9 @@ bool GBAThreadStart(struct GBAThread* threadContext) {
 		threadContext->fpsTarget = _defaultFPSTarget;
 	}
 
-	if (threadContext->rom && !GBAIsROM(threadContext->rom)) {
+	bool bootBios = threadContext->bootBios && threadContext->bios;
+
+	if (threadContext->rom && (!GBAIsROM(threadContext->rom) || bootBios)) {
 		threadContext->rom->close(threadContext->rom);
 		threadContext->rom = 0;
 	}
@@ -427,7 +429,7 @@ bool GBAThreadStart(struct GBAThread* threadContext) {
 
 	}
 
-	if (!threadContext->rom) {
+	if (!threadContext->rom && !bootBios) {
 		threadContext->state = THREAD_SHUTDOWN;
 		return false;
 	}

src/gba/supervisor/thread.h

@@ -72,6 +72,7 @@ struct GBAThread {
 	struct GBAAVStream* stream;
 	struct Configuration* overrides;
 	enum GBAIdleLoopOptimization idleOptimization;
+	bool bootBios;
 
 	bool hasOverride;
 	struct GBACartridgeOverride override;

src/platform/qt/GameController.cpp

@@ -247,7 +247,18 @@ void GameController::loadGame(const QString& path, bool dirmode) {
 	openGame();
 }
 
-void GameController::openGame() {
+void GameController::bootBIOS() {
+	closeGame();
+	m_fname = QString();
+	m_dirmode = false;
+	openGame(true);
+}
+
+void GameController::openGame(bool biosOnly) {
+	if (biosOnly && (!m_useBios || m_bios.isNull())) {
+		return;
+	}
+
 	m_gameOpen = true;
 
 	m_pauseAfterFrame = false;
@@ -261,25 +272,30 @@ void GameController::openGame() {
 	}
 
 	m_threadContext.gameDir = 0;
-	m_threadContext.fname = strdup(m_fname.toLocal8Bit().constData());
-	if (m_dirmode) {
-		m_threadContext.gameDir = VDirOpen(m_threadContext.fname);
-		m_threadContext.stateDir = m_threadContext.gameDir;
+	m_threadContext.bootBios = biosOnly;
+	if (biosOnly) {
+		m_threadContext.fname = nullptr;
 	} else {
-		m_threadContext.rom = VFileOpen(m_threadContext.fname, O_RDONLY);
+		m_threadContext.fname = strdup(m_fname.toLocal8Bit().constData());
+		if (m_dirmode) {
+			m_threadContext.gameDir = VDirOpen(m_threadContext.fname);
+			m_threadContext.stateDir = m_threadContext.gameDir;
+		} else {
+			m_threadContext.rom = VFileOpen(m_threadContext.fname, O_RDONLY);
 #if USE_LIBZIP
-		if (!m_threadContext.gameDir) {
-			m_threadContext.gameDir = VDirOpenZip(m_threadContext.fname, 0);
-		}
+			if (!m_threadContext.gameDir) {
+				m_threadContext.gameDir = VDirOpenZip(m_threadContext.fname, 0);
+			}
 #endif
 #if USE_LZMA
-		if (!m_threadContext.gameDir) {
-			m_threadContext.gameDir = VDirOpen7z(m_threadContext.fname, 0);
-		}
+			if (!m_threadContext.gameDir) {
+				m_threadContext.gameDir = VDirOpen7z(m_threadContext.fname, 0);
+			}
 #endif
+		}
 	}
 
-	if (!m_bios.isNull() &&m_useBios) {
+	if (!m_bios.isNull() && m_useBios) {
 		m_threadContext.bios = VFileDevice::open(m_bios, O_RDONLY);
 	} else {
 		m_threadContext.bios = nullptr;

src/platform/qt/GameController.h

@@ -102,7 +102,7 @@ public slots:
 	void loadPatch(const QString& path);
 	void importSharkport(const QString& path);
 	void exportSharkport(const QString& path);
-	void openGame();
+	void bootBIOS();
 	void closeGame();
 	void setPaused(bool paused);
 	void reset();
@@ -148,6 +148,7 @@ public slots:
 	void disableLogLevel(int);
 
 private slots:
+	void openGame(bool bios = false);
 	void crashGame(const QString& crashMessage);
 
 	void pollEvents();

src/platform/qt/Window.cpp

@@ -482,7 +482,9 @@ void Window::gameStarted(GBAThread* context) {
 	foreach (QAction* action, m_gameActions) {
 		action->setDisabled(false);
 	}
-	appendMRU(context->fname);
+	if (context->fname) {
+		appendMRU(context->fname);
+	}
 	updateTitle();
 	attachWidget(m_display);
 
@@ -609,6 +611,7 @@ void Window::setupMenu(QMenuBar* menubar) {
 	addControlledAction(fileMenu, fileMenu->addAction(tr("Load &ROM..."), this, SLOT(selectROM()), QKeySequence::Open), "loadROM");
 	addControlledAction(fileMenu, fileMenu->addAction(tr("Load &BIOS..."), this, SLOT(selectBIOS())), "loadBIOS");
 	addControlledAction(fileMenu, fileMenu->addAction(tr("Load &patch..."), this, SLOT(selectPatch())), "loadPatch");
+	addControlledAction(fileMenu, fileMenu->addAction(tr("Boot BIOS"), m_controller, SLOT(bootBIOS())), "bootBIOS");
 
 	m_mruMenu = fileMenu->addMenu(tr("Recent"));