Intel Extensible Firmware Interface Specification page 156

Extensible Firmware Interface Specification
6.2 DEVICE_IO Protocol
Summary
Provides the basic Memory, I/O, and PCI interfaces that are used to abstract accesses to devices.
GUID
#define DEVICE_IO_PROTOCOL \
{ af6ac311-84c3-11d2-8e3c-00a0c969723b }
Protocol Interface Structure
typedef struct _EFI_DEVICE_IO_INTERFACE {
EFI_IO_ACCESS
EFI_IO_ACCESS
EFI_IO_ACCESS
EFI_IO_MAP
EFI_PCI_DEVICE_PATH
EFI_IO_UNMAP
EFI_IO_ALLOCATE_BUFFER
EFI_IO_FLUSH
EFI_IO_FREE_BUFFER
} EFI_DEVICE_IO_INTERFACE;
Parameters
Mem
Io
Pci
Map
PciDevicePath
Unmap
AllocateBuffer
Flush
FreeBuffer
138
Allows reads and writes to memory mapped I/O space. See
Section 6.2.1.
Allows reads and writes to I/O space. See Section 6.2.1.
Allows reads and writes to PCI configuration space. See Section 6.2.1.
Provides the device specific addresses needed to access system memory
for DMA.
Provides an EFI Device Path for a PCI device with the given PCI
configuration space address.
Releases any resources allocated by Map.
Allocates pages that are suitable for a common buffer mapping.
Flushes any posted write data to the device.
Free pages that were allocated with AllocateBuffer().
12/12/00
Mem;
Io;
Pci;
Map;
PciDevicePath;
Unmap;
AllocateBuffer;
Flush;
FreeBuffer;
Version 1.02