Intel Extensible Firmware Interface, Спецификация

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Extensible Firmware Interface Specification
144 12/12/00 Version 1.02
6.2.3 DEVICE_IO.Map()
Summary
Provides the device specific addresses needed to access system memory.
Prototype
typedef
EFI_STATUS
(EFIAPI *EFI_IO_MAP) (
IN EFI_DEVICE_IO_INTERFACE *This,
IN EFI_IO_OPERATION_TYPE Operation,
IN EFI_PHYSICAL_ADDRESS *HostAddress,
IN OUT UINTN *NumberOfBytes,
OUT EFI_PHYSICAL_ADDRESS *DeviceAddress,
OUT VOID **Mapping
);
Parameters
This
A pointer to the
EFI_DEVICE_IO_INTERFACE
instance. Type
EFI_DEVICE_IO_INTERFACE
is defined in Section 6.2.
Operation
Indicates if the bus master is going to read or write to system memory.
Type
EFI_IO_OPERATION_TYPE
is defined in “Related Definitions”.
HostAddress
The system memory address to map to the device. Type
EFI_
PHYSICAL_ADDRESS
is defined in Chapter 3.
NumberOfBytes
On input the number of bytes to map.
On output the number of bytes that were mapped.
DeviceAddress
The resulting map address for the bus master device to use to access the
hosts
HostAddress
. Type
EFI_ PHYSICAL_ADDRESS
is defined in
Chapter 3.
Mapping
A resulting value to pass to
Unmap()
.