Efi_simple_network.nvdata(), Nvdata(), Func – Intel Extensible Firmware Interface User Manual
Page 624
Extensible Firmware Interface Specification
15-18
12/01/02
Version 1.10
EFI_SIMPLE_NETWORK.NvData()
Summary
Performs read and write operations on the NVRAM device attached to a network interface.
Prototype
EFI_STATUS
(EFIAPI *EFI_SIMPLE_NETWORK_NVDATA) (
IN
EFI_SIMPLE_NETWORK
*This
IN
BOOLEAN
ReadWrite,
IN
UINTN
Offset,
IN
UINTN
BufferSize,
IN OUT VOID
*Buffer
);
Parameters
This
A pointer to the
instance.
ReadWrite
TRUE
for read operations,
FALSE
for write operations.
Offset
Byte offset in the NVRAM device at which to start the read or
write operation. This must be a multiple of
NvRamAccessSize
and less than
NvRamSize
. (See
BufferSize
The number of bytes to read or write from the NVRAM device.
This must also be a multiple of
NvramAccessSize
.
Buffer
A pointer to the data buffer.
Description
This function performs read and write operations on the NVRAM device attached to a network
interface. If
ReadWrite
is TRUE, a read operation is performed. If
ReadWrite
is FALSE, a
write operation is performed.
Offset
specifies the byte offset at which to start either operation.
Offset
must be a multiple of
NvRamAccessSize
, and it must have a value between zero and
NvRamSize
.
BufferSize
specifies the length of the read or write operation.
BufferSize
must also be a
multiple of
NvRamAccessSize
, and
Offset
+
BufferSize
must not exceed
NvRamSize
.
If any of the above conditions is not met, then
EFI_INVALID_PARAMETER
will be returned.
If all the conditions are met and the operation is “read,” the NVRAM device attached to the
network interface will be read into
Buffer
and
EFI_SUCCESS
will be returned. If this is a write
operation, the contents of
Buffer
will be used to update the contents of the NVRAM device
attached to the network interface and
EFI_SUCCESS
will be returned.