SimpleFbDxe: Attempt to flush cache after every blit; didn't work

Pixel3XL/SimpleFbDxe/SimpleFbDxe.c

@@ -11,6 +11,7 @@
 #include <Protocol/GraphicsOutput.h>
 #include <Library/BaseLib.h>
 #include <Library/FrameBufferBltLib.h>
+#include <Library/CacheMaintenanceLib.h>
 
 /// Defines
 /*
@@ -189,6 +190,11 @@ DisplayBlt
              );
   gBS->RestoreTPL (Tpl);
 
+  // zhuowei: hack: flush the cache manually since my memory maps are still broken
+  WriteBackInvalidateDataCacheRange((void*)mDisplay.Mode->FrameBufferBase, 
+    mDisplay.Mode->FrameBufferSize);
+  // zhuowei: end hack
+
   return RETURN_ERROR (Status) ? EFI_INVALID_PARAMETER : EFI_SUCCESS;
 }
 

Pixel3XL/SimpleFbDxe/SimpleFbDxe.inf

@@ -28,6 +28,7 @@
   DebugLib
   PcdLib
   FrameBufferBltLib
+  CacheMaintenanceLib
 
 [Protocols]
   gEfiGraphicsOutputProtocolGuid ## PRODUCES