@@ -184,6 +184,7 @@ GBASavedataUnmask(&gba->memory.savedata);
 	}
 
 	gba->cpuBlocked = false;
+	gba->earlyExit = false;
 	if (gba->yankedRomSize) {
 		gba->memory.romSize = gba->yankedRomSize;
 		gba->memory.romMask = toPow2(gba->memory.romSize) - 1;
@@ -238,7 +239,6 @@
 	int32_t nextEvent = cpu->nextEvent;
 	while (cpu->cycles >= nextEvent) {
 		int32_t cycles = cpu->cycles;
-		int32_t testEvent;
 
 		cpu->cycles = 0;
 		cpu->nextEvent = INT_MAX;
@@ -253,14 +253,10 @@ do {
 			nextEvent = mTimingTick(&gba->timing, nextEvent);
 		} while (gba->cpuBlocked);
 
-		testEvent = GBASIOProcessEvents(&gba->sio, cycles);
-		if (testEvent < nextEvent) {
-			nextEvent = testEvent;
-		}
-
 		cpu->nextEvent = nextEvent;
 
-		if (nextEvent == 0) {
+		if (gba->earlyExit) {
+			gba->earlyExit = false;
 			break;
 		}
 		if (cpu->halted) {

@@ -106,6 +106,7 @@ uint32_t idleLoop;
 	uint32_t lastJump;
 	bool haltPending;
 	bool cpuBlocked;
+	bool earlyExit;
 	int idleDetectionStep;
 	int idleDetectionFailures;
 	int32_t cachedRegisters[16];

@@ -174,10 +174,3 @@ return sio->activeDriver->writeRegister(sio->activeDriver, address, value);
 	}
 	return value;
 }
-
-int32_t GBASIOProcessEvents(struct GBASIO* sio, int32_t cycles) {
-	if (sio->activeDriver && sio->activeDriver->processEvents) {
-		return sio->activeDriver->processEvents(sio->activeDriver, cycles);
-	}
-	return INT_MAX;
-}

@@ -78,6 +78,4 @@ void GBASIOWriteRCNT(struct GBASIO* sio, uint16_t value);
 void GBASIOWriteSIOCNT(struct GBASIO* sio, uint16_t value);
 uint16_t GBASIOWriteRegister(struct GBASIO* sio, uint32_t address, uint16_t value);
 
-int32_t GBASIOProcessEvents(struct GBASIO* sio, int32_t cycles);
-
 #endif

@@ -17,8 +17,7 @@ static bool GBASIOLockstepNodeLoad(struct GBASIODriver* driver);
 static bool GBASIOLockstepNodeUnload(struct GBASIODriver* driver);
 static uint16_t GBASIOLockstepNodeMultiWriteRegister(struct GBASIODriver* driver, uint32_t address, uint16_t value);
 static uint16_t GBASIOLockstepNodeNormalWriteRegister(struct GBASIODriver* driver, uint32_t address, uint16_t value);
-static int32_t GBASIOLockstepNodeProcessEvents(struct GBASIODriver* driver, int32_t cycles);
-static int32_t GBASIOLockstepNodeProcessEvents(struct GBASIODriver* driver, int32_t cycles);
+static void _GBASIOLockstepNodeProcessEvents(struct mTiming* timing, void* driver, uint32_t cyclesLate);
 
 void GBASIOLockstepInit(struct GBASIOLockstep* lockstep) {
 	lockstep->players[0] = 0;
@@ -47,7 +46,6 @@ node->d.deinit = GBASIOLockstepNodeDeinit;
 	node->d.load = GBASIOLockstepNodeLoad;
 	node->d.unload = GBASIOLockstepNodeUnload;
 	node->d.writeRegister = 0;
-	node->d.processEvents = GBASIOLockstepNodeProcessEvents;
 }
 
 bool GBASIOLockstepAttachNode(struct GBASIOLockstep* lockstep, struct GBASIOLockstepNode* node) {
@@ -83,6 +81,9 @@ bool GBASIOLockstepNodeInit(struct GBASIODriver* driver) {
 	struct GBASIOLockstepNode* node = (struct GBASIOLockstepNode*) driver;
 	node->d.p->multiplayerControl.slave = node->id > 0;
 	mLOG(GBA_SIO, DEBUG, "Lockstep %i: Node init", node->id);
+	node->event.context = node;
+	node->event.name = "GBA SIO Lockstep";
+	node->event.callback = _GBASIOLockstepNodeProcessEvents;
 	return true;
 }
 
@@ -94,6 +95,7 @@ bool GBASIOLockstepNodeLoad(struct GBASIODriver* driver) {
 	struct GBASIOLockstepNode* node = (struct GBASIOLockstepNode*) driver;
 	node->nextEvent = 0;
 	node->eventDiff = 0;
+	mTimingSchedule(&driver->p->p->timing, &node->event, 0);
 	node->mode = driver->p->mode;
 	switch (node->mode) {
 	case SIO_MULTI:
@@ -130,6 +132,7 @@ default:
 		break;
 	}
 	node->p->unload(node->p, node->id);
+	mTimingDeschedule(&driver->p->p->timing, &node->event);
 	return true;
 }
 
@@ -142,7 +145,8 @@ if (!node->id && node->d.p->multiplayerControl.ready) {
 				mLOG(GBA_SIO, DEBUG, "Lockstep %i: Transfer initiated", node->id);
 				node->p->transferActive = TRANSFER_STARTING;
 				node->p->transferCycles = GBASIOCyclesPerTransfer[node->d.p->multiplayerControl.baud][node->p->attached - 1];
-				node->nextEvent = 0;
+				mTimingDeschedule(&driver->p->p->timing, &node->event);
+				mTimingSchedule(&driver->p->p->timing, &node->event, 0);
 			} else {
 				value &= ~0x0080;
 			}
@@ -332,28 +336,33 @@ }
 	return 0;
 }
 
-static int32_t GBASIOLockstepNodeProcessEvents(struct GBASIODriver* driver, int32_t cycles) {
-	struct GBASIOLockstepNode* node = (struct GBASIOLockstepNode*) driver;
+static void _GBASIOLockstepNodeProcessEvents(struct mTiming* timing, void* user, uint32_t cyclesLate) {
+	struct GBASIOLockstepNode* node = user;
 	if (node->p->attached < 2) {
-		return INT_MAX;
+		return;
 	}
-	node->eventDiff += cycles;
-	node->nextEvent -= cycles;
+	int32_t cycles = 0;
+	node->nextEvent -= cyclesLate;
 	if (node->nextEvent <= 0) {
 		if (!node->id) {
 			cycles = _masterUpdate(node);
 		} else {
 			cycles = _slaveUpdate(node);
-			node->nextEvent += node->p->useCycles(node->p, node->id, node->eventDiff);
+			cycles += node->p->useCycles(node->p, node->id, node->eventDiff);
 		}
 		node->eventDiff = 0;
 	} else {
 		cycles = node->nextEvent;
 	}
-	if (cycles < 0) {
-		return 0;
+	if (cycles > 0) {
+		node->nextEvent = 0;
+		node->eventDiff += cycles;
+		mTimingDeschedule(timing, &node->event);
+		mTimingSchedule(timing, &node->event, cycles);
+	} else {
+		node->d.p->p->earlyExit = true;
+		mTimingSchedule(timing, &node->event, cyclesLate + 1);
 	}
-	return cycles;
 }
 
 static uint16_t GBASIOLockstepNodeNormalWriteRegister(struct GBASIODriver* driver, uint32_t address, uint16_t value) {

@@ -6,6 +6,7 @@ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #ifndef SIO_LOCKSTEP_H
 #define SIO_LOCKSTEP_H
 
+#include "core/timing.h"
 #include "gba/sio.h"
 
 enum GBASIOLockstepPhase {
@@ -41,6 +42,7 @@
 struct GBASIOLockstepNode {
 	struct GBASIODriver d;
 	struct GBASIOLockstep* p;
+	struct mTimingEvent event;
 
 	volatile int32_t nextEvent;
 	int32_t eventDiff;