OvmfPkg: Make the VirtIo devices use the new VIRTIO_DEVICE_PROTOCOL

This change replaces the accesses to the PCI bus from the Block, Scsi and Net drivers by
the use of the new VIRTIO_DEVICE_PROTOCOL protocol that abstracts the transport layer.
It means these drivers can be used on PCI and MMIO transport layer.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>

v5:
- VirtioFlush(): update comment block in VirtioLib.[hc]; error code is
  propagated from VirtIo->SetQueueNotify().
- VirtioBlkInit(): jump to Failed label if SetPageSize() fails
- VirtioBlkInit(): fixup comment, and add error handling, near
  SetQueueNum() call
- VirtioBlkDriverBindingStart(): remove redundant (always false) check for
  a subsystem device ID different from VIRTIO_SUBSYSTEM_BLOCK_DEVICE;
  VirtioBlkDriverBindingSupported() handles it already
- VirtioNetGetFeatures(): update stale comment block
- VirtioNetGetFeatures(): retrieve MAC address byte for byte (open-coded
  loop)
- VirtioNetDriverBindingStart(): remove redundant (always false) check for
  a subsystem device ID different from VIRTIO_SUBSYSTEM_NETWORK_CARD;
  VirtioNetDriverBindingSupported() handles it already
- VirtioNetInitRing(): call SetQueueNum() and SetQueueAlign() for proper
  MMIO operation
- VirtioNetInitialize(): fix destination error label for when
  SetPageSize() fails
- VirtioScsi.c: fix comment block of VIRTIO_CFG_WRITE()/VIRTIO_CFG_READ()
- VirtioScsiInit(): fix destination error label for when SetPageSize()
  fails
- VirtioScsiInit(): call SetQueueNum() and SetQueueAlign() for proper MMIO
  operation

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

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14966 6f19259b-4bc3-4df7-8a09-765794883524

3 files changed, 83 insertions, 121 deletions

diff --git a/OvmfPkg/VirtioScsiDxe/VirtioScsi.c b/OvmfPkg/VirtioScsiDxe/VirtioScsi.c
index b836fb3e6a..2223c9c33e 100644
--- a/OvmfPkg/VirtioScsiDxe/VirtioScsi.c
+++ b/OvmfPkg/VirtioScsiDxe/VirtioScsi.c
@@ -38,7 +38,6 @@
 

 **/

 

-#include <IndustryStandard/Pci.h>

 #include <IndustryStandard/VirtioScsi.h>

 #include <Library/BaseMemoryLib.h>

 #include <Library/DebugLib.h>

@@ -51,15 +50,14 @@
 

 /**

 

-  Convenience macros to read and write region 0 IO space elements of the

-  virtio-scsi PCI device, for configuration purposes.

+  Convenience macros to read and write configuration elements of the

+  virtio-scsi VirtIo device.

 

   The following macros make it possible to specify only the "core parameters"

   for such accesses and to derive the rest. By the time VIRTIO_CFG_WRITE()

   returns, the transaction will have been completed.

 

-  @param[in] Dev       Pointer to the VSCSI_DEV structure whose PCI IO space

-                       we're accessing. Dev->PciIo must be valid.

+  @param[in] Dev       Pointer to the VSCSI_DEV structure.

 

   @param[in] Field     A field name from VSCSI_HDR, identifying the virtio-scsi

                        configuration item to access.

@@ -72,19 +70,19 @@
                        one of UINT8, UINT16, UINT32, UINT64.

 

 

-  @return  Status codes returned by VirtioWrite() / VirtioRead().

+  @return  Status codes returned by VirtioWriteDevice() / VirtioReadDevice().

 

 **/

 

-#define VIRTIO_CFG_WRITE(Dev, Field, Value)  (VirtioWrite (              \

-                                                (Dev)->PciIo,            \

+#define VIRTIO_CFG_WRITE(Dev, Field, Value)  (VirtioWriteDevice (        \

+                                                (Dev)->VirtIo,           \

                                                 OFFSET_OF_VSCSI (Field), \

                                                 SIZE_OF_VSCSI (Field),   \

                                                 (Value)                  \

                                                 ))

 

-#define VIRTIO_CFG_READ(Dev, Field, Pointer) (VirtioRead (               \

-                                                (Dev)->PciIo,            \

+#define VIRTIO_CFG_READ(Dev, Field, Pointer) (VirtioReadDevice (         \

+                                                (Dev)->VirtIo,           \

                                                 OFFSET_OF_VSCSI (Field), \

                                                 SIZE_OF_VSCSI (Field),   \

                                                 sizeof *(Pointer),       \

@@ -471,7 +469,7 @@ VirtioScsiPassThru (
   // EFI_NOT_READY would save us the effort, but it would also suggest that the

   // caller retry.

   //

-  if (VirtioFlush (Dev->PciIo, VIRTIO_SCSI_REQUEST_QUEUE, &Dev->Ring,

+  if (VirtioFlush (Dev->VirtIo, VIRTIO_SCSI_REQUEST_QUEUE, &Dev->Ring,

         &Indices) != EFI_SUCCESS) {

     Packet->InTransferLength  = 0;

     Packet->OutTransferLength = 0;

@@ -718,19 +716,27 @@ VirtioScsiInit (
   // Execute virtio-0.9.5, 2.2.1 Device Initialization Sequence.

   //

   NextDevStat = 0;             // step 1 -- reset device

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  Status = Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, NextDevStat);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

 

   NextDevStat |= VSTAT_ACK;    // step 2 -- acknowledge device presence

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  Status = Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, NextDevStat);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

 

   NextDevStat |= VSTAT_DRIVER; // step 3 -- we know how to drive it

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  Status = Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, NextDevStat);

+  if (EFI_ERROR (Status)) {

+    goto Failed;

+  }

+

+  //

+  // Set Page Size - MMIO VirtIo Specific

+  //

+  Status = Dev->VirtIo->SetPageSize (Dev->VirtIo, EFI_PAGE_SIZE);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -738,13 +744,13 @@ VirtioScsiInit (
   //

   // step 4a -- retrieve and validate features

   //

-  Status = VIRTIO_CFG_READ (Dev, Generic.VhdrDeviceFeatureBits, &Features);

+  Status = Dev->VirtIo->GetDeviceFeatures (Dev->VirtIo, &Features);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

   Dev->InOutSupported = !!(Features & VIRTIO_SCSI_F_INOUT);

 

-  Status = VIRTIO_CFG_READ (Dev, VhdrMaxChannel, &MaxChannel);

+  Status = VIRTIO_CFG_READ (Dev, MaxChannel, &MaxChannel);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -756,7 +762,7 @@ VirtioScsiInit (
     goto Failed;

   }

 

-  Status = VIRTIO_CFG_READ (Dev, VhdrNumQueues, &NumQueues);

+  Status = VIRTIO_CFG_READ (Dev, NumQueues, &NumQueues);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -765,7 +771,7 @@ VirtioScsiInit (
     goto Failed;

   }

 

-  Status = VIRTIO_CFG_READ (Dev, VhdrMaxTarget, &Dev->MaxTarget);

+  Status = VIRTIO_CFG_READ (Dev, MaxTarget, &Dev->MaxTarget);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -773,7 +779,7 @@ VirtioScsiInit (
     Dev->MaxTarget = PcdGet16 (PcdVirtioScsiMaxTargetLimit);

   }

 

-  Status = VIRTIO_CFG_READ (Dev, VhdrMaxLun, &Dev->MaxLun);

+  Status = VIRTIO_CFG_READ (Dev, MaxLun, &Dev->MaxLun);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -781,7 +787,7 @@ VirtioScsiInit (
     Dev->MaxLun = PcdGet32 (PcdVirtioScsiMaxLunLimit);

   }

 

-  Status = VIRTIO_CFG_READ (Dev, VhdrMaxSectors, &Dev->MaxSectors);

+  Status = VIRTIO_CFG_READ (Dev, MaxSectors, &Dev->MaxSectors);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -797,12 +803,11 @@ VirtioScsiInit (
   //

   // step 4b -- allocate request virtqueue

   //

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueSelect,

-             VIRTIO_SCSI_REQUEST_QUEUE);

+  Status = Dev->VirtIo->SetQueueSel (Dev->VirtIo, VIRTIO_SCSI_REQUEST_QUEUE);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

-  Status = VIRTIO_CFG_READ (Dev, Generic.VhdrQueueSize, &QueueSize);

+  Status = Dev->VirtIo->GetQueueNumMax (Dev->VirtIo, &QueueSize);

   if (EFI_ERROR (Status)) {

     goto Failed;

   }

@@ -820,11 +825,24 @@ VirtioScsiInit (
   }

 

   //

-  // step 4c -- Report GPFN (guest-physical frame number) of queue. If anything

-  // fails from here on, we must release the ring resources.

+  // Additional steps for MMIO: align the queue appropriately, and set the

+  // size. If anything fails from here on, we must release the ring resources.

   //

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrQueueAddress,

-             (UINTN) Dev->Ring.Base >> EFI_PAGE_SHIFT);

+  Status = Dev->VirtIo->SetQueueNum (Dev->VirtIo, QueueSize);

+  if (EFI_ERROR (Status)) {

+    goto ReleaseQueue;

+  }

+

+  Status = Dev->VirtIo->SetQueueAlign (Dev->VirtIo, EFI_PAGE_SIZE);

+  if (EFI_ERROR (Status)) {

+    goto ReleaseQueue;

+  }

+

+  //

+  // step 4c -- Report GPFN (guest-physical frame number) of queue.

+  //

+  Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo,

+      (UINT32)(UINTN) Dev->Ring.Base >> EFI_PAGE_SHIFT);

   if (EFI_ERROR (Status)) {

     goto ReleaseQueue;

   }

@@ -834,8 +852,8 @@ VirtioScsiInit (
   // the known (or unknown) VIRTIO_SCSI_F_* or VIRTIO_F_* capabilities (see

   // virtio-0.9.5, Appendices B and I), except bidirectional transfers.

   //

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrGuestFeatureBits,

-             Features & VIRTIO_SCSI_F_INOUT);

+  Status = Dev->VirtIo->SetGuestFeatures (Dev->VirtIo,

+      Features & VIRTIO_SCSI_F_INOUT);

   if (EFI_ERROR (Status)) {

     goto ReleaseQueue;

   }

@@ -844,11 +862,11 @@ VirtioScsiInit (
   // We expect these maximum sizes from the host. Since they are

   // guest-negotiable, ask for them rather than just checking them.

   //

-  Status = VIRTIO_CFG_WRITE (Dev, VhdrCdbSize, VIRTIO_SCSI_CDB_SIZE);

+  Status = VIRTIO_CFG_WRITE (Dev, CdbSize, VIRTIO_SCSI_CDB_SIZE);

   if (EFI_ERROR (Status)) {

     goto ReleaseQueue;

   }

-  Status = VIRTIO_CFG_WRITE (Dev, VhdrSenseSize, VIRTIO_SCSI_SENSE_SIZE);

+  Status = VIRTIO_CFG_WRITE (Dev, SenseSize, VIRTIO_SCSI_SENSE_SIZE);

   if (EFI_ERROR (Status)) {

     goto ReleaseQueue;

   }

@@ -857,7 +875,7 @@ VirtioScsiInit (
   // step 6 -- initialization complete

   //

   NextDevStat |= VSTAT_DRIVER_OK;

-  Status = VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  Status = Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, NextDevStat);

   if (EFI_ERROR (Status)) {

     goto ReleaseQueue;

   }

@@ -901,10 +919,10 @@ ReleaseQueue:
 Failed:

   //

   // Notify the host about our failure to setup: virtio-0.9.5, 2.2.2.1 Device

-  // Status. PCI IO access failure here should not mask the original error.

+  // Status. VirtIo access failure here should not mask the original error.

   //

   NextDevStat |= VSTAT_FAILED;

-  VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, NextDevStat);

+  Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, NextDevStat);

 

   Dev->InOutSupported = FALSE;

   Dev->MaxTarget      = 0;

@@ -928,7 +946,7 @@ VirtioScsiUninit (
   // VIRTIO_CFG_WRITE() returns, the host will have learned to stay away from

   // the old comms area.

   //

-  VIRTIO_CFG_WRITE (Dev, Generic.VhdrDeviceStatus, 0);

+  Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, 0);

 

   Dev->InOutSupported = FALSE;

   Dev->MaxTarget      = 0;

@@ -953,11 +971,8 @@ VirtioScsiUninit (
 // The implementation follows:

 // - Driver Writer's Guide for UEFI 2.3.1 v1.01

 //   - 5.1.3.4 OpenProtocol() and CloseProtocol()

-//   - 18      PCI Driver Design Guidelines

-//   - 18.3    PCI drivers

 // - UEFI Spec 2.3.1 + Errata C

 //   -  6.3 Protocol Handler Services

-//   - 13.4 EFI PCI I/O Protocol

 //

 

 EFI_STATUS

@@ -968,57 +983,37 @@ VirtioScsiDriverBindingSupported (
   IN EFI_DEVICE_PATH_PROTOCOL    *RemainingDevicePath

   )

 {

-  EFI_STATUS          Status;

-  EFI_PCI_IO_PROTOCOL *PciIo;

-  PCI_TYPE00          Pci;

+  EFI_STATUS             Status;

+  VIRTIO_DEVICE_PROTOCOL *VirtIo;

 

   //

-  // Attempt to open the device with the PciIo set of interfaces. On success,

-  // the protocol is "instantiated" for the PCI device. Covers duplicate open

+  // Attempt to open the device with the VirtIo set of interfaces. On success,

+  // the protocol is "instantiated" for the VirtIo device. Covers duplicate open

   // attempts (EFI_ALREADY_STARTED).

   //

   Status = gBS->OpenProtocol (

                   DeviceHandle,               // candidate device

-                  &gEfiPciIoProtocolGuid,     // for generic PCI access

-                  (VOID **)&PciIo,            // handle to instantiate

+                  &gVirtioDeviceProtocolGuid, // for generic VirtIo access

+                  (VOID **)&VirtIo,           // handle to instantiate

                   This->DriverBindingHandle,  // requestor driver identity

                   DeviceHandle,               // ControllerHandle, according to

                                               // the UEFI Driver Model

-                  EFI_OPEN_PROTOCOL_BY_DRIVER // get exclusive PciIo access to

+                  EFI_OPEN_PROTOCOL_BY_DRIVER // get exclusive VirtIo access to

                                               // the device; to be released

                   );

   if (EFI_ERROR (Status)) {

     return Status;

   }

 

-  //

-  // Read entire PCI configuration header for more extensive check ahead.

-  //

-  Status = PciIo->Pci.Read (

-                        PciIo,                        // (protocol, device)

-                                                      // handle

-                        EfiPciIoWidthUint32,          // access width & copy

-                                                      // mode

-                        0,                            // Offset

-                        sizeof Pci / sizeof (UINT32), // Count

-                        &Pci                          // target buffer

-                        );

-

-  if (Status == EFI_SUCCESS) {

-    //

-    // virtio-0.9.5, 2.1 PCI Discovery

-    //

-    Status = (Pci.Hdr.VendorId == 0x1AF4 &&

-              Pci.Hdr.DeviceId >= 0x1000 && Pci.Hdr.DeviceId <= 0x103F &&

-              Pci.Hdr.RevisionID == 0x00 &&

-              Pci.Device.SubsystemID == VIRTIO_SUBSYSTEM_SCSI_HOST) ? EFI_SUCCESS : EFI_UNSUPPORTED;

+  if (VirtIo->SubSystemDeviceId != VIRTIO_SUBSYSTEM_SCSI_HOST) {

+    Status = EFI_UNSUPPORTED;

   }

 

   //

-  // We needed PCI IO access only transitorily, to see whether we support the

+  // We needed VirtIo access only transitorily, to see whether we support the

   // device or not.

   //

-  gBS->CloseProtocol (DeviceHandle, &gEfiPciIoProtocolGuid,

+  gBS->CloseProtocol (DeviceHandle, &gVirtioDeviceProtocolGuid,

          This->DriverBindingHandle, DeviceHandle);

   return Status;

 }

@@ -1040,43 +1035,19 @@ VirtioScsiDriverBindingStart (
     return EFI_OUT_OF_RESOURCES;

   }

 

-  Status = gBS->OpenProtocol (DeviceHandle, &gEfiPciIoProtocolGuid,

-                  (VOID **)&Dev->PciIo, This->DriverBindingHandle,

+  Status = gBS->OpenProtocol (DeviceHandle, &gVirtioDeviceProtocolGuid,

+                  (VOID **)&Dev->VirtIo, This->DriverBindingHandle,

                   DeviceHandle, EFI_OPEN_PROTOCOL_BY_DRIVER);

   if (EFI_ERROR (Status)) {

     goto FreeVirtioScsi;

   }

 

   //

-  // We must retain and ultimately restore the original PCI attributes of the

-  // device. See Driver Writer's Guide for UEFI 2.3.1 v1.01, 18.3 PCI drivers /

-  // 18.3.2 Start() and Stop().

-  //

-  // The third parameter ("Attributes", input) is ignored by the Get operation.

-  // The fourth parameter ("Result", output) is ignored by the Enable and Set

-  // operations.

-  //

-  // For virtio-scsi we only need IO space access.

-  //

-  Status = Dev->PciIo->Attributes (Dev->PciIo, EfiPciIoAttributeOperationGet,

-                         0, &Dev->OriginalPciAttributes);

-  if (EFI_ERROR (Status)) {

-    goto ClosePciIo;

-  }

-

-  Status = Dev->PciIo->Attributes (Dev->PciIo,

-                         EfiPciIoAttributeOperationEnable,

-                         EFI_PCI_IO_ATTRIBUTE_IO, NULL);

-  if (EFI_ERROR (Status)) {

-    goto ClosePciIo;

-  }

-

-  //

-  // PCI IO access granted, configure virtio-scsi device.

+  // VirtIo access granted, configure virtio-scsi device.

   //

   Status = VirtioScsiInit (Dev);

   if (EFI_ERROR (Status)) {

-    goto RestorePciAttributes;

+    goto CloseVirtIo;

   }

 

   //

@@ -1096,12 +1067,8 @@ VirtioScsiDriverBindingStart (
 UninitDev:

   VirtioScsiUninit (Dev);

 

-RestorePciAttributes:

-  Dev->PciIo->Attributes (Dev->PciIo, EfiPciIoAttributeOperationSet,

-                Dev->OriginalPciAttributes, NULL);

-

-ClosePciIo:

-  gBS->CloseProtocol (DeviceHandle, &gEfiPciIoProtocolGuid,

+CloseVirtIo:

+  gBS->CloseProtocol (DeviceHandle, &gVirtioDeviceProtocolGuid,

          This->DriverBindingHandle, DeviceHandle);

 

 FreeVirtioScsi:

@@ -1149,10 +1116,7 @@ VirtioScsiDriverBindingStop (
 

   VirtioScsiUninit (Dev);

 

-  Dev->PciIo->Attributes (Dev->PciIo, EfiPciIoAttributeOperationSet,

-                Dev->OriginalPciAttributes, NULL);

-

-  gBS->CloseProtocol (DeviceHandle, &gEfiPciIoProtocolGuid,

+  gBS->CloseProtocol (DeviceHandle, &gVirtioDeviceProtocolGuid,

          This->DriverBindingHandle, DeviceHandle);

 

   FreePool (Dev);

diff --git a/OvmfPkg/VirtioScsiDxe/VirtioScsi.h b/OvmfPkg/VirtioScsiDxe/VirtioScsi.h
index f5220b2215..0d3181d140 100644
--- a/OvmfPkg/VirtioScsiDxe/VirtioScsi.h
+++ b/OvmfPkg/VirtioScsiDxe/VirtioScsi.h
@@ -20,7 +20,6 @@
 

 #include <Protocol/ComponentName.h>

 #include <Protocol/DriverBinding.h>

-#include <Protocol/PciIo.h>

 #include <Protocol/ScsiPassThruExt.h>

 

 #include <IndustryStandard/Virtio.h>

@@ -49,18 +48,17 @@ typedef struct {
   // at various call depths. The table to the right should make it easier to

   // track them.

   //

-  //                              field                     init function       init depth

-  //                              ----------------------    ------------------  ----------

-  UINT32                          Signature;             // DriverBindingStart  0

-  EFI_PCI_IO_PROTOCOL             *PciIo;                // DriverBindingStart  0

-  UINT64                          OriginalPciAttributes; // DriverBindingStart  0

-  BOOLEAN                         InOutSupported;        // VirtioScsiInit      1

-  UINT16                          MaxTarget;             // VirtioScsiInit      1

-  UINT32                          MaxLun;                // VirtioScsiInit      1

-  UINT32                          MaxSectors;            // VirtioScsiInit      1

-  VRING                           Ring;                  // VirtioRingInit      2

-  EFI_EXT_SCSI_PASS_THRU_PROTOCOL PassThru;              // VirtioScsiInit      1

-  EFI_EXT_SCSI_PASS_THRU_MODE     PassThruMode;          // VirtioScsiInit      1

+  //                              field              init function       init depth

+  //                              ----------------   ------------------  ----------

+  UINT32                          Signature;      // DriverBindingStart  0

+  VIRTIO_DEVICE_PROTOCOL          *VirtIo;        // DriverBindingStart  0

+  BOOLEAN                         InOutSupported; // VirtioScsiInit      1

+  UINT16                          MaxTarget;      // VirtioScsiInit      1

+  UINT32                          MaxLun;         // VirtioScsiInit      1

+  UINT32                          MaxSectors;     // VirtioScsiInit      1

+  VRING                           Ring;           // VirtioRingInit      2

+  EFI_EXT_SCSI_PASS_THRU_PROTOCOL PassThru;       // VirtioScsiInit      1

+  EFI_EXT_SCSI_PASS_THRU_MODE     PassThruMode;   // VirtioScsiInit      1

 } VSCSI_DEV;

 

 #define VIRTIO_SCSI_FROM_PASS_THRU(PassThruPointer) \

diff --git a/OvmfPkg/VirtioScsiDxe/VirtioScsi.inf b/OvmfPkg/VirtioScsiDxe/VirtioScsi.inf
index 8209c50275..7558112393 100644
--- a/OvmfPkg/VirtioScsiDxe/VirtioScsi.inf
+++ b/OvmfPkg/VirtioScsiDxe/VirtioScsi.inf
@@ -40,7 +40,7 @@
 

 [Protocols]

   gEfiExtScsiPassThruProtocolGuid  ## BY_START

-  gEfiPciIoProtocolGuid            ## TO_START

+  gVirtioDeviceProtocolGuid        ## TO_START

 

 [Pcd]

   gUefiOvmfPkgTokenSpaceGuid.PcdVirtioScsiMaxTargetLimit ## CONSUMES