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GBA Timer: More timer improvements

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This commit is contained in:
Vicki Pfau 2017-07-05 19:28:38 -07:00
parent db08a75d9b
commit 7c59350e9d
5 changed files with 70 additions and 38 deletions
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1
include/mgba/internal/gba/gba.h
View File

@ -79,7 +79,6 @@ struct GBA {
uint32_t bus;
int performingDMA;
struct mTimingEvent timerMaster;
struct GBATimer timers[4];
int springIRQ;

4
include/mgba/internal/gba/serialize.h
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@ -264,10 +264,10 @@ struct GBASerializedState {
struct {
uint16_t reload;
uint16_t oldReload;
uint16_t reserved;
uint32_t lastEvent;
uint32_t nextEvent;
int32_t overflowInterval;
uint32_t nextIrq;
GBATimerFlags flags;
} timers[4];

2
include/mgba/internal/gba/timer.h
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@ -17,12 +17,14 @@ DECL_BITS(GBATimerFlags, PrescaleBits, 0, 4);
DECL_BIT(GBATimerFlags, CountUp, 4);
DECL_BIT(GBATimerFlags, DoIrq, 5);
DECL_BIT(GBATimerFlags, Enable, 6);
DECL_BIT(GBATimerFlags, IrqPending, 7);
struct GBA;
struct GBATimer {
uint16_t reload;
int32_t lastEvent;
struct mTimingEvent event;
struct mTimingEvent irq;
GBATimerFlags flags;
};

9
src/gba/io.c
View File

@ -928,6 +928,7 @@ void GBAIOSerialize(struct GBA* gba, struct GBASerializedState* state) {
STORE_16(gba->timers[i].reload, 0, &state->timers[i].reload);
STORE_32(gba->timers[i].lastEvent - mTimingCurrentTime(&gba->timing), 0, &state->timers[i].lastEvent);
STORE_32(gba->timers[i].event.when - mTimingCurrentTime(&gba->timing), 0, &state->timers[i].nextEvent);
STORE_32(gba->timers[i].irq.when - mTimingCurrentTime(&gba->timing), 0, &state->timers[i].nextIrq);
STORE_32(gba->timers[i].flags, 0, &state->timers[i].flags);
STORE_32(gba->memory.dma[i].nextSource, 0, &state->dma[i].nextSource);
STORE_32(gba->memory.dma[i].nextDest, 0, &state->dma[i].nextDest);
@ -951,10 +952,6 @@ void GBAIODeserialize(struct GBA* gba, const struct GBASerializedState* state) {
}
uint32_t when;
LOAD_32(when, 0, &state->masterCycles);
when += state->cpu.cycles;
when = 0x400 - (when & 0x3FF);
mTimingSchedule(&gba->timing, &gba->timerMaster, when);
for (i = 0; i < 4; ++i) {
LOAD_16(gba->timers[i].reload, 0, &state->timers[i].reload);
LOAD_32(gba->timers[i].flags, 0, &state->timers[i].flags);
@ -969,6 +966,10 @@ void GBAIODeserialize(struct GBA* gba, const struct GBASerializedState* state) {
if (GBATimerFlagsIsEnable(gba->timers[i].flags)) {
mTimingSchedule(&gba->timing, &gba->timers[i].event, when);
}
LOAD_32(when, 0, &state->timers[i].nextIrq);
if (GBATimerFlagsIsIrqPending(gba->timers[i].flags)) {
mTimingSchedule(&gba->timing, &gba->timers[i].irq, when);
}
LOAD_16(gba->memory.dma[i].reg, (REG_DMA0CNT_HI + i * 12), state->io);
LOAD_32(gba->memory.dma[i].nextSource, 0, &state->dma[i].nextSource);

92
src/gba/timer.c
View File

@ -8,7 +8,39 @@
#include <mgba/internal/gba/gba.h>
#include <mgba/internal/gba/io.h>
#define TIMER_MASTER 1024
#define TIMER_IRQ_DELAY 7
static void GBATimerIrq(struct GBA* gba, int timerId) {
struct GBATimer* timer = &gba->timers[timerId];
if (GBATimerFlagsIsIrqPending(timer->flags)) {
timer->flags = GBATimerFlagsClearIrqPending(timer->flags);
GBARaiseIRQ(gba, IRQ_TIMER0 + timerId);
}
}
static void GBATimerIrq0(struct mTiming* timing, void* context, uint32_t cyclesLate) {
UNUSED(timing);
UNUSED(cyclesLate);
GBATimerIrq(context, 0);
}
static void GBATimerIrq1(struct mTiming* timing, void* context, uint32_t cyclesLate) {
UNUSED(timing);
UNUSED(cyclesLate);
GBATimerIrq(context, 1);
}
static void GBATimerIrq2(struct mTiming* timing, void* context, uint32_t cyclesLate) {
UNUSED(timing);
UNUSED(cyclesLate);
GBATimerIrq(context, 2);
}
static void GBATimerIrq3(struct mTiming* timing, void* context, uint32_t cyclesLate) {
UNUSED(timing);
UNUSED(cyclesLate);
GBATimerIrq(context, 3);
}
static void GBATimerUpdate(struct GBA* gba, int timerId, uint32_t cyclesLate) {
struct GBATimer* timer = &gba->timers[timerId];
@ -20,7 +52,10 @@ static void GBATimerUpdate(struct GBA* gba, int timerId, uint32_t cyclesLate) {
GBATimerUpdateRegister(gba, timerId, 0);
if (GBATimerFlagsIsDoIrq(timer->flags)) {
GBARaiseIRQ(gba, IRQ_TIMER0 + timerId);
timer->flags = GBATimerFlagsFillIrqPending(timer->flags);
if (!mTimingIsScheduled(&gba->timing, &timer->irq)) {
mTimingSchedule(&gba->timing, &timer->irq, TIMER_IRQ_DELAY - cyclesLate);
}
}
if (gba->audio.enable && timerId < 2) {
@ -44,15 +79,6 @@ static void GBATimerUpdate(struct GBA* gba, int timerId, uint32_t cyclesLate) {
}
}
static void GBATimerMasterUpdate(struct mTiming* timing, void* context, uint32_t cyclesLate) {
struct GBA* gba = context;
mTimingSchedule(timing, &gba->timerMaster, TIMER_MASTER - cyclesLate);
GBATimerUpdateRegister(gba, 0, cyclesLate);
GBATimerUpdateRegister(gba, 1, cyclesLate);
GBATimerUpdateRegister(gba, 2, cyclesLate);
GBATimerUpdateRegister(gba, 3, cyclesLate);
}
static void GBATimerUpdate0(struct mTiming* timing, void* context, uint32_t cyclesLate) {
UNUSED(timing);
GBATimerUpdate(context, 0, cyclesLate);
@ -74,28 +100,39 @@ static void GBATimerUpdate3(struct mTiming* timing, void* context, uint32_t cycl
}
void GBATimerInit(struct GBA* gba) {
gba->timerMaster.name = "GBA Timer Master";
gba->timerMaster.callback = GBATimerMasterUpdate;
gba->timerMaster.context = gba;
gba->timerMaster.priority = 0x20;
mTimingSchedule(&gba->timing, &gba->timerMaster, TIMER_MASTER);
memset(gba->timers, 0, sizeof(gba->timers));
gba->timers[0].event.name = "GBA Timer 0";
gba->timers[0].event.callback = GBATimerUpdate0;
gba->timers[0].event.context = gba;
gba->timers[0].event.priority = 0x21;
gba->timers[0].event.priority = 0x20;
gba->timers[1].event.name = "GBA Timer 1";
gba->timers[1].event.callback = GBATimerUpdate1;
gba->timers[1].event.context = gba;
gba->timers[1].event.priority = 0x22;
gba->timers[1].event.priority = 0x21;
gba->timers[2].event.name = "GBA Timer 2";
gba->timers[2].event.callback = GBATimerUpdate2;
gba->timers[2].event.context = gba;
gba->timers[2].event.priority = 0x23;
gba->timers[2].event.priority = 0x22;
gba->timers[3].event.name = "GBA Timer 3";
gba->timers[3].event.callback = GBATimerUpdate3;
gba->timers[3].event.context = gba;
gba->timers[3].event.priority = 0x24;
gba->timers[3].event.priority = 0x23;
gba->timers[0].irq.name = "GBA Timer 0 IRQ";
gba->timers[0].irq.callback = GBATimerIrq0;
gba->timers[0].irq.context = gba;
gba->timers[0].irq.priority = 0x28;
gba->timers[1].irq.name = "GBA Timer 1 IRQ";
gba->timers[1].irq.callback = GBATimerIrq1;
gba->timers[1].irq.context = gba;
gba->timers[1].irq.priority = 0x29;
gba->timers[2].irq.name = "GBA Timer 2 IRQ";
gba->timers[2].irq.callback = GBATimerIrq2;
gba->timers[2].irq.context = gba;
gba->timers[2].irq.priority = 0x2A;
gba->timers[3].irq.name = "GBA Timer 3 IRQ";
gba->timers[3].irq.callback = GBATimerIrq3;
gba->timers[3].irq.context = gba;
gba->timers[3].irq.priority = 0x2B;
}
void GBATimerUpdateRegister(struct GBA* gba, int timer, int32_t cyclesLate) {
@ -117,17 +154,10 @@ void GBATimerUpdateRegister(struct GBA* gba, int timer, int32_t cyclesLate) {
tickIncrement >>= prescaleBits;
tickIncrement += gba->memory.io[(REG_TM0CNT_LO + (timer << 2)) >> 1];
gba->memory.io[(REG_TM0CNT_LO + (timer << 2)) >> 1] = tickIncrement;
tickIncrement -= 0x10000;
mTimingDeschedule(&gba->timing, &currentTimer->event);
if (tickIncrement >= 0) {
mTimingSchedule(&gba->timing, &currentTimer->event, 7 - (tickIncrement << prescaleBits));
} else {
int32_t nextIncrement = mTimingUntil(&gba->timing, &gba->timerMaster);
tickIncrement = -tickIncrement;
tickIncrement <<= prescaleBits;
if (nextIncrement - tickIncrement > 0) {
mTimingSchedule(&gba->timing, &currentTimer->event, 7 + tickIncrement);
}
if (!mTimingIsScheduled(&gba->timing, &currentTimer->event)) {
tickIncrement = (0x10000 - tickIncrement) << prescaleBits;
currentTime -= mTimingCurrentTime(&gba->timing) - cyclesLate;
mTimingSchedule(&gba->timing, &currentTimer->event, tickIncrement + currentTime);
}
}