[PATCH v3 08/23] OvmfPkg/Virtio10Dxe: add the RingBaseShift offset

[Brijesh Singh <brijesh.singh@amd.com>]

virtio drivers use VIRTIO_DEVICE_PROTOCOL.MapSharedBuffer() to map the
ring buffer host address to a device address. If an IOMMU is present then
RingBaseShift contains the offset from the host address.

Suggested-by: Laszlo Ersek <lersek@redhat.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 OvmfPkg/Virtio10Dxe/Virtio10.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/OvmfPkg/Virtio10Dxe/Virtio10.c b/OvmfPkg/Virtio10Dxe/Virtio10.c
index ef9a00710668..e9b50b6e437b 100644
--- a/OvmfPkg/Virtio10Dxe/Virtio10.c
+++ b/OvmfPkg/Virtio10Dxe/Virtio10.c
@@ -498,11 +498,10 @@ Virtio10SetQueueAddress (
   UINT64         Address;
   UINT16         Enable;
 
-  ASSERT (RingBaseShift == 0);
-
   Dev = VIRTIO_1_0_FROM_VIRTIO_DEVICE (This);
 
   Address = (UINTN)Ring->Desc;
+  Address += RingBaseShift;
   Status = Virtio10Transfer (Dev->PciIo, &Dev->CommonConfig, TRUE,
              OFFSET_OF (VIRTIO_PCI_COMMON_CFG, QueueDesc),
              sizeof Address, &Address);
@@ -511,6 +510,7 @@ Virtio10SetQueueAddress (
   }
 
   Address = (UINTN)Ring->Avail.Flags;
+  Address += RingBaseShift;
   Status = Virtio10Transfer (Dev->PciIo, &Dev->CommonConfig, TRUE,
              OFFSET_OF (VIRTIO_PCI_COMMON_CFG, QueueAvail),
              sizeof Address, &Address);
@@ -519,6 +519,7 @@ Virtio10SetQueueAddress (
   }
 
   Address = (UINTN)Ring->Used.Flags;
+  Address += RingBaseShift;
   Status = Virtio10Transfer (Dev->PciIo, &Dev->CommonConfig, TRUE,
              OFFSET_OF (VIRTIO_PCI_COMMON_CFG, QueueUsed),
              sizeof Address, &Address);
-- 
2.7.4