[GPU] Move VBLANK interrupt to the scheduler

src/gpu/gpu.cpp

@@ -3,13 +3,30 @@
 
 MAKE_LOG_FUNCTION(log, gpuLogger)
 
+void GPU::scanlineEvent(void* classptr) {
+	GPU* gpu = (GPU*)classptr;
+	
+	if (gpu->currentScanline < GPUConstants::scanlinesPerVdraw) {
+		gpu->stat ^= 1 << 31;	// Interlacing
+	}
+	else if (gpu->currentScanline == GPUConstants::scanlinesPerVdraw) {
+		gpu->vblank = true;
+	}
+	else if (gpu->currentScanline == GPUConstants::scanlinesPerFrame) {
+		gpu->currentScanline = 0;
+	}
+
+	gpu->currentScanline++;
+
+	gpu->scheduler->push(scanlineEvent, gpu->scheduler->time + GPUConstants::cyclesPerScanline, gpu);
+}
+
 u32 GPU::getStat() {
 	// Stubbed
 	stat |= 1 << 26;	// Ready to receive cmd word
 	stat |= 1 << 27;	// Ready to send VRAM to CPU
 	stat |= 1 << 28;	// Ready to receive DMA block
 	stat |= 1 << 30;	// DMA direction CPU -> GP0
-	stat ^= 1 << 31;	// Fake interlacing
 	return stat;
 }
 

src/gpu/gpu.hpp

@@ -5,14 +5,29 @@
 #include <logger.hpp>
 #include <backends/software/gpu_software.hpp>
 #include <backends/base.hpp>
+#include <scheduler.hpp>
 
 
+namespace GPUConstants {
+// TODO: PAL?
+constexpr u64 cyclesPerHdraw = 2560 / 1.57;
+constexpr u64 cyclesPerScanline = 3413 / 1.57;	// NTSC
+constexpr u64 scanlinesPerVdraw = 240;
+constexpr u64 scanlinesPerFrame = 263;
+} // End namespace GPUConstants
+
 class GPU {
 public:
-	GPU() : software(this) {
+	GPU(Scheduler* scheduler) : software(this), scheduler(scheduler) {
 		backend = &software;
 	}
 
+	Scheduler* scheduler;
+
+	u64 currentScanline = 0;
+	static void scanlineEvent(void* classptr);
+	bool vblank = false;
+
 	bool uploadingTexture = false;
 	std::vector<u32> fifo;
 	u32 getStat();
@@ -49,7 +64,6 @@ public:
 		DisplayMode				= 0x08
 	};
 
-
 private:
 	u32 stat = 0x14802000;
 

src/main.cpp

@@ -3,8 +3,6 @@
 #include "playstation.hpp"
 
 
-int cyclesPerFrame = 521520;
-
 int main(int argc, char** argv) {
     if (argc < 2) Helpers::panic("Usage: ChonkyStation [bios path]\n");
 
@@ -22,12 +20,11 @@ int main(int argc, char** argv) {
     while (running) {
         playstation.cycles = 0;
 
-        while (playstation.cycles < cyclesPerFrame)
+        while (!playstation.getVBLANKAndClear())
             playstation.step();
 
         // VBLANK interrupt
         playstation.VBLANK();
-        cyclesPerFrame = 33868800 / 60;
 
         // Handle SDL window events
         SDL_Event event;

src/playstation.hpp

@@ -12,9 +12,12 @@
 
 class PlayStation {
 public:
-    PlayStation(const fs::path& biosPath) : cdrom(), interrupt(), gpu(), dma(), mem(&interrupt, &dma, &gpu, &cdrom), cpu(&mem) {
+    PlayStation(const fs::path& biosPath) : cdrom(), interrupt(), gpu(&scheduler), dma(), mem(&interrupt, &dma, &gpu, &cdrom), cpu(&mem) {
         mem.loadBios(biosPath);
         cpu.switchBackend(Cpu::Backend::Interpreter);
+
+        // Setup GPU scheduler events
+        scheduler.push(&gpu.scanlineEvent, scheduler.time + GPUConstants::cyclesPerScanline, &gpu);
     }
 
     u64 cycles = 0;
@@ -29,6 +32,11 @@ public:
     u32 getPC() { return cpu.core.pc; }
     u8* getRAM() { return mem.ram; }
     u8* getVRAM() { return gpu.getVRAM(); }
+    bool getVBLANKAndClear() {
+        bool temp = gpu.vblank;
+        gpu.vblank = false;
+        return temp;
+    }
     void VBLANK() { interrupt.raiseInterrupt(Interrupt::InterruptType::VBLANK); }
     bool isInBIOS() { return Helpers::inRangeSized<u32>(cpu.core.pc, (u32)Memory::MemoryBase::BIOS, (u32)Memory::MemorySize::BIOS); }