whb: Handle GPU hangs by resetting the GPU on shutdown.

So your application will exit cleanly even when you break the GPU.

include/gx2/state.h

@@ -21,6 +21,9 @@ GX2Shutdown();
 void
 GX2Flush();
 
+void
+GX2ResetGPU(uint32_t unknown);
+
 #ifdef __cplusplus
 }
 #endif

src/libwhb/src/gfx.c

@@ -64,6 +64,9 @@ sTvContextState = NULL;
 static GX2ContextState *
 sDrcContextState = NULL;
 
+static BOOL
+sGpuTimedOut = FALSE;
+
 static void *
 GfxGX2RAlloc(GX2RResourceFlags flags,
              uint32_t size,
@@ -426,6 +429,11 @@ error:
 void
 WHBGfxShutdown()
 {
+   if (sGpuTimedOut) {
+      GX2ResetGPU(0);
+      sGpuTimedOut = FALSE;
+   }
+
    GfxProcCallbackReleased(NULL);
    GX2Shutdown();
 
@@ -452,14 +460,24 @@ WHBGfxBeginRender()
 {
    uint32_t swapCount, flipCount;
    OSTime lastFlip, lastVsync;
+   uint32_t waitCount = 0;
 
    while (true) {
-      GX2WaitForVsync();
       GX2GetSwapStatus(&swapCount, &flipCount, &lastFlip, &lastVsync);
 
       if (flipCount >= swapCount) {
+         sGpuTimedOut = FALSE;
          break;
       }
+
+      if (waitCount >= 10) {
+         WHBLogPrint("WHBGfxBeginRender wait for swap timed out");
+         sGpuTimedOut = TRUE;
+         break;
+      }
+
+      waitCount++;
+      GX2WaitForVsync();
    }
 }
 

src/rpl/gx2/exports.h

@@ -140,6 +140,7 @@ EXPORT(GX2InitSamplerZMFilter);
 EXPORT(GX2Flush);
 EXPORT(GX2Init);
 EXPORT(GX2Shutdown);
+EXPORT(GX2ResetGPU);
 
 // gx2/shader.h
 EXPORT(GX2CalcGeometryShaderInputRingBufferSize);