Intel Extensible Firmware Interface, Specification

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32/64-bit UNDI Specification
Version 1.02 12/12/00 437
G.4.10 Interrupt Enables
The Interrupt Enables command can be used to read and/or change the current external interrupt
enable settings. Disabling an external interrupt enable prevents an external (hardware) interrupt
from being signaled by the network device, internally the interrupt events can still be polled by
using the Get Status command.
G.4.10.1 Issuing the Command
To issue an Interrupt Enables command, create a CDB and fill it in as shows in the table below:
CDB Field How to initialize the CDB structure for an Interrupt Enables command
OpCode PXE_OPCODE_INTERRUPT_ENABLES
OpFlags Set as needed.
CPBsize PXE_CPBSIZE_NOT_USED
DBsize PXE_DBSIZE_NOT_USED
CPBaddr PXE_CPBADDR_NOT_USED
DBaddr PXE_DBADDR_NOT_USED
StatCode PXE_STATCODE_INITIALIZE
StatFlags PXE_STATFLAGS_INITIALIZE
IFnum
A valid interface number from zero to
!PXE.IFcnt
.
Control Set as needed.
OpFlags
To read the current external interrupt enables settings set
CDB.OpFlags
to:
•
PXE_OPFLAGS_INTERRUPT_READ
To enable or disable external interrupts set one of these OpFlags:
•
PXE_OPFLAGS_INTERRUPT_DISABLE
•
PXE_OPFLAGS_INTERRUPT_ENABLE
When enabling or disabling interrupt settings, the following additional OpFlag bits are used to
specify which types of external interrupts are to be enabled or disabled:
•
PXE_OPFLAGS_INTERRUPT_RECEIVE
•
PXE_OPFLAGS_INTERRUPT_TRANSMIT
•
PXE_OPFLAGS_INTERRUPT_COMMAND
•
PXE_OPFLAGS_INTERRUPT_SOFTWARE
Setting
PXE_OPFLAGS_INTERRUPT_SOFTWARE
does not enable an external interrupt type, it
generates an external interrupt.