Specification Sheet

Datasheet, Volume 2 of 2 315
VC0PREMAP Registers
10.6 Root-Entry Table Address Register (RTADDR)—
Offset 20h
Register providing the base address of root-entry table.
Access Method
Default: 0h
24
0h
RO_V
IRTPS: This field indicates the status of the interrupt remapping table pointer in
hardware.
This field is cleared by hardware when software sets the SIRTP field in the Global
Command register. This field is Set by hardware when hardware completes the set
interrupt remap table pointer operation using the value provided in the Interrupt
Remapping Table Address register.
23
0h
RO_V
CFIS: This field indicates the status of Compatibility format interrupts on Intel®64
implementations supporting interrupt-remapping. The value reported in this field is
applicable only when interrupt-remapping is enabled and Extended Interrupt Mode
(x2APIC mode) is not enabled.
0: Compatibility format interrupts are blocked.
1: Compatibility format interrupts are processed as pass-through (bypassing interrupt
remapping).
22:0
0h
RO
Reserved (RSVD): Reserved.
Bit
Range
Default &
Access
Field Name (ID): Description
Type: MEM
(Size: 64 bits)
Offset: [B:0, D:0, F:0] + 20h
6
3
6
0
5
6
5
2
4
8
4
4
4
0
3
6
3
2
2
8
2
4
2
0
1
6
1
2
8 4 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
RSVD
RTA
RTT
RSVD
Bit
Range
Default &
Access
Field Name (ID): Description
63:39
0h
RO
Reserved (RSVD): Reserved.
38:12
0h
RW
RTA: This register points to base of page aligned, 4KB-sized root-entry table in
system memory. Hardware ignores and not implements bits 63:HAW, where HAW is
the host address width.
Software specifies the base address of the root-entry table through this register, and
programs it in hardware through the SRTP field in the Global Command register.
Reads of this register returns value that was last programmed to it.
11
0h
RO
RTT: PLACEHOLDER: This field specifies the type of root-table referenced by the Root
Table Address (RTA) field;
0: Root Table
1: Extended Root Table
10:0
0h
RO
Reserved (RSVD): Reserved.