/** @file
Virtio Device
DISCLAIMER: the VIRTIO_DEVICE_PROTOCOL introduced here is a work in progress,
and should not be used outside of the EDK II tree.
Copyright (c) 2013, ARM Ltd. All rights reserved.<BR>
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_DEVICE_H__
#define __VIRTIO_DEVICE_H__
#include <IndustryStandard/Virtio.h>
// VirtIo Specification Revision: Major[31:24].Minor[23:16].Revision[15:0
#define VIRTIO_SPEC_REVISION(major,minor,revision) \
((((major) & 0xFF) << 24) | (((minor) & 0xFF) << 16) | ((revision) & 0xFFFF))
#define VIRTIO_DEVICE_PROTOCOL_GUID { \
0xfa920010, 0x6785, 0x4941, {0xb6, 0xec, 0x49, 0x8c, 0x57, 0x9f, 0x16, 0x0a }\
}
typedef struct _VIRTIO_DEVICE_PROTOCOL VIRTIO_DEVICE_PROTOCOL;
/**
Read a word from the device-specific I/O region of the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] FieldOffset Source offset.
@param[in] FieldSize Source field size in bytes, must be in {1, 2, 4, 8}.
@param[in] BufferSize Number of bytes available in the target buffer. Must
equal FieldSize.
@param[out] Buffer Target buffer.
@retval EFI_SUCCESS The data was read successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and read size.
@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a
lack of resources.
@retval EFI_INVALID_PARAMETER One or more parameters are invalid.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_DEVICE_READ) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINTN FieldOffset,
IN UINTN FieldSize,
IN UINTN BufferSize,
OUT VOID *Buffer
);
/**
Write a word to the device-specific I/O region of the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] FieldOffset Destination offset.
@param[in] FieldSize Destination field size in bytes,
must be in {1, 2, 4, 8}.
@param[out] Value Value to write.
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
@retval EFI_OUT_OF_RESOURCES The request could not be completed due to a
lack of resources.
@retval EFI_INVALID_PARAMETER One or more parameters are invalid.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_DEVICE_WRITE) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINTN FieldOffset,
IN UINTN FieldSize,
IN UINT64 Value
);
/**
Read the device features field from the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[out] DeviceFeatures The device features field.
@retval EFI_SUCCESS The data was read successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and read size.
@retval EFI_INVALID_PARAMETER DeviceFeatures is NULL
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_GET_DEVICE_FEATURES) (
IN VIRTIO_DEVICE_PROTOCOL *This,
OUT UINT64 *DeviceFeatures
);
/**
Write the guest features field in the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] Features The guest features field
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_GUEST_FEATURES) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT64 Features
);
/**
Write the queue address field(s) in the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] Ring The initialized VRING object to take the
addresses from.
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_QUEUE_ADDRESS) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN VRING *Ring
);
/**
Write the queue select field in the Virtio Header.
Writing to the queue select field sets the index of the queue to which
operations such as SetQueueAlign and GetQueueNumMax apply.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] Index The index of the queue to select
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_QUEUE_SEL) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT16 Index
);
/**
Write the queue notify field in the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] Address The 32-bit Queue Notify field
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_QUEUE_NOTIFY) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT16 Index
);
/**
Write the queue alignment field in the Virtio Header.
The queue to which the alignment applies is selected by the Queue Select
field.
Note: This operation is not implemented by the VirtIo over PCI. The PCI
implementation of this protocol returns EFI_SUCCESS.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] Alignment The alignment boundary of the Used Ring in bytes.
Must be a power of 2.
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_QUEUE_ALIGN) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT32 Alignment
);
/**
Write the guest page size.
Note: This operation is not implemented by the VirtIo over PCI. The PCI
implementation of this protocol returns EFI_SUCCESS.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] PageSize Size of the Guest page in bytes.
Must be a power of 2.
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_PAGE_SIZE) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT32 PageSize
);
/**
Get the size of the virtqueue selected by the queue select field.
See Virtio spec Section 2.3
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[out] QueueNumMax The size of the virtqueue in bytes.
Always a power of 2.
@retval EFI_SUCCESS The data was read successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and read size.
@retval EFI_INVALID_PARAMETER QueueNumMax is NULL
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_GET_QUEUE_NUM_MAX) (
IN VIRTIO_DEVICE_PROTOCOL *This,
OUT UINT16 *QueueNumMax
);
/**
Write to the QueueNum field in the Virtio Header.
This function only applies to Virtio-MMIO and may be a stub for other
implementations. See Virtio Spec appendix X.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] QueueSize The number of elements in the queue.
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_QUEUE_NUM) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT16 QueueSize
);
/**
Get the DeviceStatus field from the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[out] DeviceStatus The 8-bit value for the Device status field
@retval EFI_SUCCESS The data was read successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and read size.
@retval EFI_INVALID_PARAMETER DeviceStatus is NULL
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_GET_DEVICE_STATUS) (
IN VIRTIO_DEVICE_PROTOCOL *This,
OUT UINT8 *DeviceStatus
);
/**
Write the DeviceStatus field in the Virtio Header.
@param[in] This This instance of VIRTIO_DEVICE_PROTOCOL
@param[in] DeviceStatus The 8-bit value for the Device status field
@retval EFI_SUCCESS The data was written successfully.
@retval EFI_UNSUPPORTED The underlying IO device doesn't support the
provided address offset and write size.
**/
typedef
EFI_STATUS
(EFIAPI *VIRTIO_SET_DEVICE_STATUS) (
IN VIRTIO_DEVICE_PROTOCOL *This,
IN UINT8 DeviceStatus
);
///
/// This protocol provides an abstraction over the VirtIo transport layer
///
/// DISCLAIMER: this protocol is a work in progress, and should not be used
/// outside of the EDK II tree.
///
struct _VIRTIO_DEVICE_PROTOCOL {
/// VirtIo Specification Revision encoded with VIRTIO_SPEC_REVISION()
UINT32 Revision;
/// From the Virtio Spec
INT32 SubSystemDeviceId;
VIRTIO_GET_DEVICE_FEATURES GetDeviceFeatures;
VIRTIO_SET_GUEST_FEATURES SetGuestFeatures;
VIRTIO_SET_QUEUE_ADDRESS SetQueueAddress;
VIRTIO_SET_QUEUE_SEL SetQueueSel;
VIRTIO_SET_QUEUE_NOTIFY SetQueueNotify;
VIRTIO_SET_QUEUE_ALIGN SetQueueAlign;
VIRTIO_SET_PAGE_SIZE SetPageSize;
VIRTIO_GET_QUEUE_NUM_MAX GetQueueNumMax;
VIRTIO_SET_QUEUE_NUM SetQueueNum;
VIRTIO_GET_DEVICE_STATUS GetDeviceStatus;
VIRTIO_SET_DEVICE_STATUS SetDeviceStatus;
// Functions to read/write Device Specific headers
VIRTIO_DEVICE_WRITE WriteDevice;
VIRTIO_DEVICE_READ ReadDevice;
};
extern EFI_GUID gVirtioDeviceProtocolGuid;
#endif