From 916f90baa547b3ebef8fa87c530e2f0c8e35e1e3 Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri, 8 Apr 2022 10:23:33 +0200
Subject: [PATCH] OvmfPkg/VirtioGpuDxe: query native display resolution from
 host

Try query native display resolution from the host.  When successful,
setup PcdVideoHorizontalResolution and PcdVideoVerticalResolution
accordingly and add the video mode to the GOP mode list if needed.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
---
 OvmfPkg/VirtioGpuDxe/Gop.c         | 92 ++++++++++++++++++++++++++++--
 OvmfPkg/VirtioGpuDxe/VirtioGpu.h   |  6 ++
 OvmfPkg/VirtioGpuDxe/VirtioGpu.inf |  6 ++
 3 files changed, 99 insertions(+), 5 deletions(-)

diff --git a/OvmfPkg/VirtioGpuDxe/Gop.c b/OvmfPkg/VirtioGpuDxe/Gop.c
index 05daefcbfb..70a81c10c8 100644
--- a/OvmfPkg/VirtioGpuDxe/Gop.c
+++ b/OvmfPkg/VirtioGpuDxe/Gop.c
@@ -9,6 +9,7 @@
 **/
 
 #include <Library/MemoryAllocationLib.h>
+#include <Library/PcdLib.h>
 
 #include "VirtioGpu.h"
 
@@ -192,6 +193,47 @@ STATIC CONST GOP_RESOLUTION  mGopResolutions[] = {
 #define VGPU_GOP_FROM_GOP(GopPointer) \
           CR (GopPointer, VGPU_GOP, Gop, VGPU_GOP_SIG)
 
+STATIC
+VOID
+EFIAPI
+GopNativeResolution (
+  IN  VGPU_GOP  *VgpuGop,
+  OUT UINT32    *XRes,
+  OUT UINT32    *YRes
+  )
+{
+  volatile VIRTIO_GPU_RESP_DISPLAY_INFO  DisplayInfo;
+  EFI_STATUS                             Status;
+  UINTN                                  Index;
+
+  Status = VirtioGpuGetDisplayInfo (VgpuGop->ParentBus, &DisplayInfo);
+  if (Status != EFI_SUCCESS) {
+    return;
+  }
+
+  for (Index = 0; Index < VIRTIO_GPU_MAX_SCANOUTS; Index++) {
+    if (!DisplayInfo.Pmodes[Index].Enabled ||
+        !DisplayInfo.Pmodes[Index].Rectangle.Width ||
+        !DisplayInfo.Pmodes[Index].Rectangle.Height)
+    {
+      continue;
+    }
+
+    DEBUG ((
+      DEBUG_INFO,
+      "%a: #%d: %dx%d\n",
+      __FUNCTION__,
+      Index,
+      DisplayInfo.Pmodes[Index].Rectangle.Width,
+      DisplayInfo.Pmodes[Index].Rectangle.Height
+      ));
+    if ((*XRes == 0) || (*YRes == 0)) {
+      *XRes = DisplayInfo.Pmodes[Index].Rectangle.Width;
+      *YRes = DisplayInfo.Pmodes[Index].Rectangle.Height;
+    }
+  }
+}
+
 STATIC
 VOID
 EFIAPI
@@ -199,7 +241,9 @@ GopInitialize (
   IN  EFI_GRAPHICS_OUTPUT_PROTOCOL  *This
   )
 {
-  VGPU_GOP  *VgpuGop;
+  VGPU_GOP    *VgpuGop;
+  EFI_STATUS  Status;
+  UINT32      XRes = 0, YRes = 0, Index;
 
   VgpuGop = VGPU_GOP_FROM_GOP (This);
 
@@ -216,6 +260,37 @@ GopInitialize (
   VgpuGop->GopMode.SizeOfInfo = sizeof VgpuGop->GopModeInfo;
 
   VgpuGop->GopModeInfo.PixelFormat = PixelBltOnly;
+
+  //
+  // query host for display resolution
+  //
+  GopNativeResolution (VgpuGop, &XRes, &YRes);
+  if ((XRes == 0) || (YRes == 0)) {
+    return;
+  }
+
+  if (PcdGet8 (PcdVideoResolutionSource) == 0) {
+    Status = PcdSet32S (PcdVideoHorizontalResolution, XRes);
+    ASSERT_RETURN_ERROR (Status);
+    Status = PcdSet32S (PcdVideoVerticalResolution, YRes);
+    ASSERT_RETURN_ERROR (Status);
+    Status = PcdSet8S (PcdVideoResolutionSource, 2);
+    ASSERT_RETURN_ERROR (Status);
+  }
+
+  VgpuGop->NativeXRes = XRes;
+  VgpuGop->NativeYRes = YRes;
+  for (Index = 0; Index < ARRAY_SIZE (mGopResolutions); Index++) {
+    if ((mGopResolutions[Index].Width == XRes) &&
+        (mGopResolutions[Index].Height == YRes))
+    {
+      // native resolution already is in mode list
+      return;
+    }
+  }
+
+  // add to mode list
+  VgpuGop->GopMode.MaxMode++;
 }
 
 //
@@ -242,10 +317,17 @@ GopQueryMode (
     return EFI_OUT_OF_RESOURCES;
   }
 
-  GopModeInfo->HorizontalResolution = mGopResolutions[ModeNumber].Width;
-  GopModeInfo->VerticalResolution   = mGopResolutions[ModeNumber].Height;
-  GopModeInfo->PixelFormat          = PixelBltOnly;
-  GopModeInfo->PixelsPerScanLine    = mGopResolutions[ModeNumber].Width;
+  if (ModeNumber < ARRAY_SIZE (mGopResolutions)) {
+    GopModeInfo->HorizontalResolution = mGopResolutions[ModeNumber].Width;
+    GopModeInfo->VerticalResolution   = mGopResolutions[ModeNumber].Height;
+  } else {
+    VGPU_GOP  *VgpuGop = VGPU_GOP_FROM_GOP (This);
+    GopModeInfo->HorizontalResolution = VgpuGop->NativeXRes;
+    GopModeInfo->VerticalResolution   = VgpuGop->NativeYRes;
+  }
+
+  GopModeInfo->PixelFormat       = PixelBltOnly;
+  GopModeInfo->PixelsPerScanLine = GopModeInfo->HorizontalResolution;
 
   *SizeOfInfo = sizeof *GopModeInfo;
   *Info       = GopModeInfo;
diff --git a/OvmfPkg/VirtioGpuDxe/VirtioGpu.h b/OvmfPkg/VirtioGpuDxe/VirtioGpu.h
index 1d781088bb..45da564152 100644
--- a/OvmfPkg/VirtioGpuDxe/VirtioGpu.h
+++ b/OvmfPkg/VirtioGpuDxe/VirtioGpu.h
@@ -151,6 +151,12 @@ struct VGPU_GOP_STRUCT {
   // BackingStore is non-NULL.
   //
   VOID                                    *BackingStoreMap;
+
+  //
+  // native display resolution
+  //
+  UINT32                                  NativeXRes;
+  UINT32                                  NativeYRes;
 };
 
 //
diff --git a/OvmfPkg/VirtioGpuDxe/VirtioGpu.inf b/OvmfPkg/VirtioGpuDxe/VirtioGpu.inf
index 9e66bcd4b9..d88c87e129 100644
--- a/OvmfPkg/VirtioGpuDxe/VirtioGpu.inf
+++ b/OvmfPkg/VirtioGpuDxe/VirtioGpu.inf
@@ -25,6 +25,7 @@
 
 [Packages]
   MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
   OvmfPkg/OvmfPkg.dec
 
 [LibraryClasses]
@@ -43,3 +44,8 @@
   gEfiGraphicsOutputProtocolGuid ## BY_START
   gEfiPciIoProtocolGuid          ## TO_START
   gVirtioDeviceProtocolGuid      ## TO_START
+
+[Pcd]
+  gUefiOvmfPkgTokenSpaceGuid.PcdVideoResolutionSource
+  gEfiMdeModulePkgTokenSpaceGuid.PcdVideoHorizontalResolution
+  gEfiMdeModulePkgTokenSpaceGuid.PcdVideoVerticalResolution
-- 
2.39.2