OvmfPkg: Add virtio keyboard device hooks

This commit adds:
- missing virtio subsystem ID for input device
- PrepareVirtioKeyboardDevicePath() handler to boot manager library

Signed-off-by: Paweł Poławski <ppolawsk@redhat.com>

OvmfPkg/Include/IndustryStandard/Virtio10.h

@@ -17,6 +17,7 @@
 // Subsystem Device IDs (to be) introduced in VirtIo 1.0
 //
 #define VIRTIO_SUBSYSTEM_GPU_DEVICE  16
+#define VIRTIO_SUBSYSTEM_INPUT       18
 //
 // Subsystem Device IDs from the VirtIo spec at git commit 87fa6b5d8155;
 // <https://github.com/oasis-tcs/virtio-spec/tree/87fa6b5d8155>.

OvmfPkg/Library/PlatformBootManagerLib/BdsPlatform.c

@@ -1111,6 +1111,28 @@ PrepareVirtioSerialDevicePath (
   return EFI_SUCCESS;
 }
 
+EFI_STATUS
+PrepareVirtioKeyboardDevicePath (
+  IN EFI_HANDLE  DeviceHandle
+  )
+{
+  EFI_STATUS                Status;
+  EFI_DEVICE_PATH_PROTOCOL  *DevicePath;
+
+  DevicePath = NULL;
+  Status     = gBS->HandleProtocol (
+                      DeviceHandle,
+                      &gEfiDevicePathProtocolGuid,
+                      (VOID *)&DevicePath
+                      );
+  if (EFI_ERROR (Status)) {
+    return Status;
+  }
+
+  EfiBootManagerUpdateConsoleVariable (ConIn, DevicePath, NULL);
+  return EFI_SUCCESS;
+}
+
 EFI_STATUS
 VisitAllInstancesOfProtocol (
   IN EFI_GUID                    *Id,
@@ -1287,6 +1309,12 @@ DetectAndPreparePlatformPciDevicePath (
     return EFI_SUCCESS;
   }
 
+  if ((Pci->Hdr.VendorId == 0x1af4) && (Pci->Hdr.DeviceId == 0x1052)) {
+    DEBUG ((DEBUG_INFO, "Found virtio keyboard device\n"));
+    PrepareVirtioKeyboardDevicePath (Handle);
+    return EFI_SUCCESS;
+  }
+
   return Status;
 }