Filter
Top Products
Protocols — Device I/O Protocol
Version 1.10 12/01/02 18-5
DEVICE_IO.Mem(), .Io(), and .Pci()
Summary
Enables a driver to access device registers in the appropriate memory or I/O space.
Prototype
typedef
EFI_STATUS
(EFIAPI *EFI_DEVICE_IO) (
IN struct EFI_DEVICE_IO_INTERFACE *This,
IN EFI_IO_WIDTH Width,
IN UINT64 Address,
IN UINTN Count,
IN OUT VOID *Buffer
);
Parameters
This A pointer to the EFI_DEVICE_IO_INTERFACE instance. Type
EFI_DEVICE_IO_INTERFACE is defined in Section 18.2.
Width Signifies the width of the I/O operations. Type EFI_IO_WIDTH
is
defined in Section 18.2.
Address The base address of the I/O operations. The caller is responsible for
aligning the Address if required.
Count The number of I/O operations to perform. Bytes moved is Width size *
Count, starting at Address.
Buffer For read operations, the destination buffer to store the results. For write
operations, the source buffer to write data from.