Intel Extensible Firmware Interface - Manual (Page 655)

Protocols — Network Support
Version 1.10 12/01/02 15-49
Description
This function attempts to complete the PXE Boot Server and/or boot image discovery sequence. If
this sequence is completed, then
EFI_SUCCESS is returned, and the PxeDiscoverValid ,
PxeDiscover , PxeReplyReceived , and PxeReply fields of the
EFI_PXE_BASE_CODE_MODE structure are filled in. If UseBis is TRUE , then the
PxeBisReplyReceived and PxeBisReply fields of the EFI_PXE_BASE_CODE_MODE
structure will also be filled in. If UseBis is FALSE , then PxeBisReplyValid will be set to
FALSE .
In the structure referenced by parameter Info , the PXE Boot Server list, SrvList[] , has two
uses: It is the Boot Server IP address list used for unicast discovery (if the UseUCast field is
TRUE ), and it is the list used for Boot Server verification (if the MustUseList field is TRUE ).
Also, if the MustUseList field in that structure is TRUE and the AcceptAnyResponse field
in the SrvList[] array is TRUE , any Boot Server reply of that type will be accepted. If the
AcceptAnyResponse field is FALSE , only responses from Boot Servers with matching IP
addresses will be accepted.
This function can take at least 10 seconds to timeout and return control to the caller. If the
Discovery sequence does not complete, then
EFI_TIMEOUT will be returned. Please see the
Preboot Execution Environment (PXE) Specification for additional details on the implementation of
the Discovery sequence.
If the Callback Protocol does not return
EFI_PXE_BASE_CODE_CALLBACK_STATUS_CONTINUE , then the Discovery sequence is
stopped and EFI_ABORTED will be returned.
Status Codes Returned
EFI_SUCCESS The Discovery sequence has been completed.
EFI_NOT_STARTED The PXE Base Code Protocol is in the stopped state.
EFI_INVALID_PARAMETER One of the parameters is not valid.
EFI_DEVICE_ERROR The network device encountered an error during this operation.
EFI_OUT_OF_RESOURCES Could not allocate enough memory to complete Discovery.
EFI_ABORTED The callback function aborted the Discovery sequence.
EFI_TIMEOUT The Discovery sequence timed out.
EFI_ICMP_ERROR The Discovery sequence generated an ICMP error.