BlockIo.h File Reference

Data Structures
struct	EFI_PEI_BLOCK_IO_MEDIA
struct	_EFI_PEI_RECOVERY_BLOCK_IO_PPI

Macros
#define	EFI_PEI_RECOVERY_BLOCK_IO_PPI_GUID

Typedefs
typedef struct _EFI_PEI_RECOVERY_BLOCK_IO_PPI	EFI_PEI_RECOVERY_BLOCK_IO_PPI
typedef UINT64	EFI_PEI_LBA
typedef EFI_STATUS(EFIAPI *	EFI_PEI_GET_NUMBER_BLOCK_DEVICES )(IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_RECOVERY_BLOCK_IO_PPI *This, OUT UINTN *NumberBlockDevices)
typedef EFI_STATUS(EFIAPI *	EFI_PEI_GET_DEVICE_MEDIA_INFORMATION )(IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_RECOVERY_BLOCK_IO_PPI *This, IN UINTN DeviceIndex, OUT EFI_PEI_BLOCK_IO_MEDIA *MediaInfo)
typedef EFI_STATUS(EFIAPI *	EFI_PEI_READ_BLOCKS )(IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_RECOVERY_BLOCK_IO_PPI *This, IN UINTN DeviceIndex, IN EFI_PEI_LBA StartLBA, IN UINTN BufferSize, OUT VOID *Buffer)

Enumerations
enum	EFI_PEI_BLOCK_DEVICE_TYPE {   LegacyFloppy = 0, IdeCDROM = 1, IdeLS120 = 2, UsbMassStorage = 3,   SD = 4, EMMC = 5, UfsDevice = 6, MaxDeviceType }

Variables
EFI_GUID	gEfiPeiVirtualBlockIoPpiGuid

Detailed Description

Provides the services required to access a block I/O device during PEI recovery boot mode.

The Recovery Module PPI and the Device Recovery Module PPI are device neutral. This PPI is device specific and addresses the most common form of recovery media-block I/O devices such as legacy floppy, CD-ROM, or IDE devices.

The Recovery Block I/O PPI is used to access block devices. Because the Recovery Block I/O PPIs that are provided by the PEI ATAPI driver and PEI legacy floppy driver are the same, here we define a set of general PPIs for both drivers to use.

Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Revision Reference:

This PPI is defined in UEFI Platform Initialization Specification 1.2 Volume 1: Pre-EFI Initialization Core Interface.

Macro Definition Documentation

#define EFI_PEI_RECOVERY_BLOCK_IO_PPI_GUID

Value:

{ \
    0x695d8aa1, 0x42ee, 0x4c46, { 0x80, 0x5c, 0x6e, 0xa6, 0xbc, 0xe7, 0x99, 0xe3 } \
  }

Global ID for EFI_PEI_RECOVERY_BLOCK_IO_PPI

Typedef Documentation

typedef EFI_STATUS(EFIAPI * EFI_PEI_GET_DEVICE_MEDIA_INFORMATION)(IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_RECOVERY_BLOCK_IO_PPI *This, IN UINTN DeviceIndex, OUT EFI_PEI_BLOCK_IO_MEDIA *MediaInfo)

Gets a block device's media information.

This function will provide the caller with the specified block device's media information. If the media changes, calling this function will update the media information accordingly.

Parameters

[in]	PeiServices	General-purpose services that are available to every PEIM
[in]	This	Indicates the EFI_PEI_RECOVERY_BLOCK_IO_PPI instance.
[in]	DeviceIndex	Specifies the block device to which the function wants to talk. Because the driver that implements Block I/O PPIs will manage multiple block devices, the PPIs that want to talk to a single device must specify the device index that was assigned during the enumeration process. This index is a number from one to NumberBlockDevices.
[out]	MediaInfo	The media information of the specified block media. The caller is responsible for the ownership of this data structure.

Note:

The MediaInfo structure describes an enumeration of possible block device types. This enumeration exists because no device paths are actually passed across interfaces that describe the type or class of hardware that is publishing the block I/O interface. This enumeration will allow for policy decisions in the Recovery PEIM, such as "Try to recover from legacy floppy first, LS-120 second, CD-ROM third." If there are multiple partitions abstracted by a given device type, they should be reported in ascending order; this order also applies to nested partitions, such as legacy MBR, where the outermost partitions would have precedence in the reporting order. The same logic applies to systems such as IDE that have precedence relationships like "Master/Slave" or "Primary/Secondary". The master device should be reported first, the slave second.

Return values

EFI_SUCCESS	Media information about the specified block device was obtained successfully.
EFI_DEVICE_ERROR	Cannot get the media information due to a hardware error.

typedef EFI_STATUS(EFIAPI * EFI_PEI_GET_NUMBER_BLOCK_DEVICES)(IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_RECOVERY_BLOCK_IO_PPI *This, OUT UINTN *NumberBlockDevices)

Gets the count of block I/O devices that one specific block driver detects.

This function is used for getting the count of block I/O devices that one specific block driver detects. To the PEI ATAPI driver, it returns the number of all the detected ATAPI devices it detects during the enumeration process. To the PEI legacy floppy driver, it returns the number of all the legacy devices it finds during its enumeration process. If no device is detected, then the function will return zero.

Parameters

[in]	PeiServices	General-purpose services that are available to every PEIM.
[in]	This	Indicates the EFI_PEI_RECOVERY_BLOCK_IO_PPI instance.
[out]	NumberBlockDevices	The number of block I/O devices discovered.

Return values

EFI_SUCCESS

The operation performed successfully.

typedef UINT64 EFI_PEI_LBA

All blocks on the recovery device are addressed with a 64-bit Logical Block Address (LBA).

typedef EFI_STATUS(EFIAPI * EFI_PEI_READ_BLOCKS)(IN EFI_PEI_SERVICES **PeiServices, IN EFI_PEI_RECOVERY_BLOCK_IO_PPI *This, IN UINTN DeviceIndex, IN EFI_PEI_LBA StartLBA, IN UINTN BufferSize, OUT VOID *Buffer)

Reads the requested number of blocks from the specified block device.

The function reads the requested number of blocks from the device. All the blocks are read, or an error is returned. If there is no media in the device, the function returns EFI_NO_MEDIA.

Parameters

[in]	PeiServices	General-purpose services that are available to every PEIM.
[in]	This	Indicates the EFI_PEI_RECOVERY_BLOCK_IO_PPI instance.
[in]	DeviceIndex	Specifies the block device to which the function wants to talk. Because the driver that implements Block I/O PPIs will manage multiple block devices, PPIs that want to talk to a single device must specify the device index that was assigned during the enumeration process. This index is a number from one to NumberBlockDevices.
[in]	StartLBA	The starting logical block address (LBA) to read from on the device
[in]	BufferSize	The size of the Buffer in bytes. This number must be a multiple of the intrinsic block size of the device.
[out]	Buffer	A pointer to the destination buffer for the data. The caller is responsible for the ownership of the buffer.

Return values

EFI_SUCCESS	The data was read correctly from the device.
EFI_DEVICE_ERROR	The device reported an error while attempting to perform the read operation.
EFI_INVALID_PARAMETER	The read request contains LBAs that are not valid, or the buffer is not properly aligned.
EFI_NO_MEDIA	There is no media in the device.
EFI_BAD_BUFFER_SIZE	The BufferSize parameter is not a multiple of the intrinsic block size of the device.

typedef struct _EFI_PEI_RECOVERY_BLOCK_IO_PPI EFI_PEI_RECOVERY_BLOCK_IO_PPI

The forward declaration for EFI_PEI_RECOVERY_BLOCK_IO_PPI.

Enumeration Type Documentation

enum EFI_PEI_BLOCK_DEVICE_TYPE

EFI_PEI_BLOCK_DEVICE_TYPE

Enumerator
LegacyFloppy	The recovery device is a floppy.
IdeCDROM	The recovery device is an IDE CD-ROM.
IdeLS120	The recovery device is an IDE LS-120.
UsbMassStorage	The recovery device is a USB Mass Storage device.
SD	The recovery device is a Secure Digital device.
EMMC	The recovery device is a eMMC device.
UfsDevice	The recovery device is a Universal Flash Storage device.
MaxDeviceType

Variable Documentation

EFI_GUID gEfiPeiVirtualBlockIoPpiGuid