Datasheet

Integrated I/O (IIO) Configuration Registers
492 Intel
®
Xeon
®
Processor E7-2800/4800/8800 v2 Product Family
Datasheet Volume Two: Functional Description, February 2014
14.10.4.1 APICID__WINDOW
This register uniquely identifies an APIC in the system. This register is not used by
OS’es anymore and is still implemented in hardware because of FUD.
14.10.4.2 VER__WINDOW
This register uniquely identifies an APIC in the system. This register is not used by
OSes anymore and is still implemented in hardware because of FUD.
RTL21__WINDOW 0x3a 32
RTH21__WINDOW 0x3b 32
RTL22__WINDOW 0x3c 32
RTH22__WINDOW 0x3d 32
RTL23__WINDOW 0x3e 32
RTH23__WINDOW 0x3f 32
Register name Offset Size
Type: MEM PortID: N/A
Bus: 0 Device: 5Function:4
Offset: 0x0
Bit Attr Default Description
31:28 RV - Reserved.
27:24 RW 0x0
apicid:
Allows for up to 16 unique APIC IDs in the system.
23:0 RV - Reserved.
Type: MEM PortID: N/A
Bus: 0 Device: 5Function:4
Offset: 0x1
Bit Attr Default Description
31:24 RV - Reserved.
23:16 RO 0x17
max:
This is the entry number of the highest entry in the redirection table. It is
equal to the number of interrupt inputs minus one. This field is hardwired to
17h to indicate 24 interrupts.
15:15 RO 0x0
prq:
This bit is set to 0 to indicate that this version of the I/OxAPIC does not
implement the IRQ Assertion register and does not allow PCI devices to write
to it to cause interrupts.
14:8 RV - Reserved.
7:0 RO 0x20
vs:
This identifies the implementation version. This field is hardwired to 20h
indicate this is an I/OxAPIC.