[PATCH v4 2/7] OvmfPkg/VirtioMmioDeviceLib: Add virtio 1.0 detection.

["Gerd Hoffmann" <kraxel@redhat.com>]

Add #defines for the Version field.  Read and store the version,
log the version found as info message.

Continue to return UNSUPPORTED for now, we need some more patches
to complete virtio 1.0 support first.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 .../VirtioMmioDeviceLib/VirtioMmioDevice.h      |  4 ++++
 .../VirtioMmioDeviceLib/VirtioMmioDevice.c      | 17 +++++++++++++----
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h
index ab53b90d51c9..0c2f99633c46 100644
--- a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h
+++ b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.h
@@ -23,9 +23,13 @@
 #include <Library/MemoryAllocationLib.h>
 
 #define VIRTIO_MMIO_DEVICE_SIGNATURE  SIGNATURE_32 ('V', 'M', 'I', 'O')
+#define VIRTIO_MMIO_DEVICE_VERSION_0_95  1
+#define VIRTIO_MMIO_DEVICE_VERSION_1_00  2
+
 
 typedef struct {
   UINT32                 Signature;
+  UINT32                 Version;
   VIRTIO_DEVICE_PROTOCOL VirtioDevice;
   PHYSICAL_ADDRESS       BaseAddress;
 } VIRTIO_MMIO_DEVICE;
diff --git a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.c b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.c
index 6dbbba008c75..0c92f5373151 100644
--- a/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.c
+++ b/OvmfPkg/Library/VirtioMmioDeviceLib/VirtioMmioDevice.c
@@ -58,7 +58,6 @@ VirtioMmioInit (
   )
 {
   UINT32     MagicValue;
-  UINT32     Version;
 
   //
   // Initialize VirtIo Mmio Device
@@ -66,7 +65,6 @@ VirtioMmioInit (
   CopyMem (&Device->VirtioDevice, &mMmioDeviceProtocolTemplate,
         sizeof (VIRTIO_DEVICE_PROTOCOL));
   Device->BaseAddress = BaseAddress;
-  Device->VirtioDevice.Revision = VIRTIO_SPEC_REVISION (0, 9, 5);
   Device->VirtioDevice.SubSystemDeviceId =
           MmioRead32 (BaseAddress + VIRTIO_MMIO_OFFSET_DEVICE_ID);
 
@@ -78,8 +76,19 @@ VirtioMmioInit (
     return EFI_UNSUPPORTED;
   }
 
-  Version = VIRTIO_CFG_READ (Device, VIRTIO_MMIO_OFFSET_VERSION);
-  if (Version != 1) {
+  Device->Version = VIRTIO_CFG_READ (Device, VIRTIO_MMIO_OFFSET_VERSION);
+  switch (Device->Version) {
+  case VIRTIO_MMIO_DEVICE_VERSION_0_95:
+    DEBUG ((DEBUG_INFO, "%a virtio 0.9.5, id %d\n", __FUNCTION__,
+            Device->VirtioDevice.SubSystemDeviceId));
+    Device->VirtioDevice.Revision = VIRTIO_SPEC_REVISION (0, 9, 5);
+    break;
+  case VIRTIO_MMIO_DEVICE_VERSION_1_00:
+    DEBUG ((DEBUG_INFO, "%a virtio 1.0, id %d\n", __FUNCTION__,
+            Device->VirtioDevice.SubSystemDeviceId));
+    Device->VirtioDevice.Revision = VIRTIO_SPEC_REVISION (1, 0, 0);
+    return EFI_UNSUPPORTED;
+  default:
     return EFI_UNSUPPORTED;
   }
 
-- 
2.31.1