OvmfPkg/QemuVideoDxe: VMWare SVGA device support

In addition to the QXL, Cirrus, etc. VGA adapters, Qemu also implements
a basic version of VMWare's SVGA display device. Drivers for this
device exist for some guest OSes which do not support Qemu's other
display adapters, so supporting it in OVMF is useful in conjunction
with those OSes.

This change adds support for the SVGA device's framebuffer to
QemuVideoDxe's graphics output protocol implementation, based on
VMWare's documentation. The most basic initialisation, framebuffer
layout query, and mode setting operations are implemented.

The device relies on port-based 32-bit I/O, unfortunately on misaligned
addresses. This limits the driver's support to the x86 family of
platforms.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Phil Dennis-Jordan <phil@philjordan.eu>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

OvmfPkg/QemuVideoDxe/Qemu.h

@@ -92,6 +92,7 @@ typedef enum {
   QEMU_VIDEO_CIRRUS_5446,
   QEMU_VIDEO_BOCHS,
   QEMU_VIDEO_BOCHS_MMIO,
+  QEMU_VIDEO_VMWARE_SVGA,
 } QEMU_VIDEO_VARIANT;
 
 typedef struct {
@@ -115,10 +116,13 @@ typedef struct {
   //
   UINTN                                 MaxMode;
   QEMU_VIDEO_MODE_DATA                  *ModeData;
+  EFI_GRAPHICS_OUTPUT_MODE_INFORMATION  *VmwareSvgaModeInfo;
 
   QEMU_VIDEO_VARIANT                    Variant;
   FRAME_BUFFER_CONFIGURE                *FrameBufferBltConfigure;
   UINTN                                 FrameBufferBltConfigureSize;
+  UINT8                                 FrameBufferVramBarIndex;
+  UINT16                                VmwareSvgaBasePort;
 } QEMU_VIDEO_PRIVATE_DATA;
 
 ///
@@ -502,9 +506,34 @@ QemuVideoBochsModeSetup (
   BOOLEAN                  IsQxl
   );
 
+EFI_STATUS
+QemuVideoVmwareSvgaModeSetup (
+  QEMU_VIDEO_PRIVATE_DATA *Private
+  );
+
 VOID
 InstallVbeShim (
   IN CONST CHAR16         *CardName,
   IN EFI_PHYSICAL_ADDRESS FrameBufferBase
   );
+
+VOID
+VmwareSvgaWrite (
+  QEMU_VIDEO_PRIVATE_DATA *Private,
+  UINT16                  Register,
+  UINT32                  Value
+  );
+
+UINT32
+VmwareSvgaRead (
+  QEMU_VIDEO_PRIVATE_DATA *Private,
+  UINT16                  Register
+  );
+
+VOID
+InitializeVmwareSvgaGraphicsMode (
+  QEMU_VIDEO_PRIVATE_DATA  *Private,
+  QEMU_VIDEO_BOCHS_MODES   *ModeData
+  );
+
 #endif