Chapter 4: UEFI BIOS
93
Intel
®
VT for Directed I/O (VT-d)
Intel® VT for Directed I/O (VT-d)
Select Enable to use Intel Virtualization Technology support for Direct I/O VT-d by reporting
the I/O device assignments to the VMM (Virtual Machine Monitor) through the DMAR
ACPI tables. This feature offers fully-protected I/O resource sharing across Intel platforms,
providing greater reliability, security and availability in networking and data-sharing. The
options are
Enable
and Disable.
ACS (Access Control Services) Control
Select Enable to program Access Control Services to Chipset PCI-E Root Port Bridges.
Select Disable to program Access Control Services to all PCI-E Root Port Bridges. The
options are
Enable
and Disable.
Interrupt Remapping
If this feature is set to Enable, I/O DMA transfer remapping and device-generated interrupts
will be supported. The options are
Enable
and Disable.
PassThrough DMA
Select Enable for the Non-Isoch VT-d engine to pass through DMA (Direct Memory Access)
to enhance system performance. The options are
Enable
and Disable.
ATS
Select Enable to enable ATS (Address Translation Services) support for the Non-Isoch VT-d
engine to enhance system performance. The options are
Enable
and Disable.
Posted Interrupt
Select Enable to support VT_D Posted Interrupt which will allow external interrupts to be
sent directly from a direct-assigned device to a client machine in non-root mode to improve
virtualization efficiency by simplifying interrupt migration and lessening the need of physical
interrupts. The options are
Enable
and Disable.
Coherency Support (Non-Isoch)
Select Enable for the Non-Isoch VT-d engine to pass through DMA (Direct Memory Access)
to enhance system performance. The options are
Enable
and Disable.
