OvmfPkg: Virtio10Dxe: non-transitional driver for virtio-1.0 PCI devices

This driver implements the VIRTIO_DEVICE_PROTOCOL for non-transitional PCI
devices, based on the virtio-1.0 specification (csprd05). Non-transitional
means that it only binds QEMU's virtio-xxx-pci devices that receive the
",disable-legacy=on,disable-modern=off" properties on the QEMU command
line. These devices have distinct PCI Device IDs from those that are bound
by VirtioPciDeviceDxe.

The central abstraction of this driver is the VIRTIO_1_0_CONFIG type. It
is practically a "fat pointer" to a register block. The pointed-to
register block
- may or may not exist (the latter being mostly useful for virtio-1.0
  devices that have no device-specific registers),
- lives in one of the device's BARs,
- lives in an IO or MMIO BAR,
- lives at an offset relative to the BAR start,
- has its size also maintained.

Such VIRTIO_1_0_CONFIG "fat pointers" (i.e., the locations of the register
blocks) are parsed from vendor capabilities that reside in the device's
standard PCI capabilities list (in PCI config space).

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jordan Justen <jordan.l.justen@intel.com>

OvmfPkg/Virtio10Dxe/Virtio10.h

@@ -0,0 +1,56 @@
+/** @file
+  Private definitions of the VirtIo 1.0 driver.
+
+  Copyright (C) 2016, Red Hat, Inc.
+
+  This program and the accompanying materials are licensed and made available
+  under the terms and conditions of the BSD License which accompanies this
+  distribution. The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+**/
+
+#ifndef _VIRTIO_1_0_DXE_H_
+#define _VIRTIO_1_0_DXE_H_
+
+#include <Protocol/PciIo.h>
+#include <Protocol/VirtioDevice.h>
+
+#define VIRTIO_1_0_SIGNATURE SIGNATURE_32 ('V', 'I', 'O', '1')
+
+//
+// Type of the PCI BAR that contains a VirtIo 1.0 config structure.
+//
+typedef enum {
+  Virtio10BarTypeMem,
+  Virtio10BarTypeIo
+} VIRTIO_1_0_BAR_TYPE;
+
+//
+// The type below defines the access to a VirtIo 1.0 config structure.
+//
+typedef struct {
+  BOOLEAN             Exists;  // The device exposes this structure
+  VIRTIO_1_0_BAR_TYPE BarType;
+  UINT8               Bar;
+  UINT32              Offset;  // Offset into BAR where structure starts
+  UINT32              Length;  // Length of structure in BAR.
+} VIRTIO_1_0_CONFIG;
+
+typedef struct {
+  UINT32                 Signature;
+  VIRTIO_DEVICE_PROTOCOL VirtIo;
+  EFI_PCI_IO_PROTOCOL    *PciIo;
+  UINT64                 OriginalPciAttributes;
+  VIRTIO_1_0_CONFIG      CommonConfig;           // Common settings
+  VIRTIO_1_0_CONFIG      NotifyConfig;           // Notifications
+  UINT32                 NotifyOffsetMultiplier;
+  VIRTIO_1_0_CONFIG      SpecificConfig;         // Device specific settings
+} VIRTIO_1_0_DEV;
+
+#define VIRTIO_1_0_FROM_VIRTIO_DEVICE(Device) \
+          CR (Device, VIRTIO_1_0_DEV, VirtIo, VIRTIO_1_0_SIGNATURE)
+
+#endif // _VIRTIO_1_0_DXE_H_

OvmfPkg/Virtio10Dxe/Virtio10.inf

@@ -0,0 +1,40 @@
+## @file
+# A non-transitional driver for VirtIo 1.0 PCI devices.
+#
+# Copyright (C) 2016, Red Hat, Inc.
+#
+# This program and the accompanying materials are licensed and made available
+# under the terms and conditions of the BSD License which accompanies this
+# distribution. The full text of the license may be found at
+# http://opensource.org/licenses/bsd-license.php
+#
+# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
+# WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = Virtio10
+  FILE_GUID                      = 0170F60C-1D40-4651-956D-F0BD9879D527
+  MODULE_TYPE                    = UEFI_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = Virtio10EntryPoint
+
+[Sources]
+  Virtio10.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  OvmfPkg/OvmfPkg.dec
+
+[LibraryClasses]
+  BaseMemoryLib
+  DebugLib
+  MemoryAllocationLib
+  UefiBootServicesTableLib
+  UefiDriverEntryPoint
+  UefiLib
+
+[Protocols]
+  gEfiPciIoProtocolGuid     ## TO_START
+  gVirtioDeviceProtocolGuid ## BY_START