Datasheet

Datasheet, Volume 2 225
Processor Configuration Registers
2.12.12 DMIVCPRCTL—DMI VCp Resource Control Register
This register controls the resources associated with the DMI Private Channel (VCp).
B/D/F/Type: 0/0/0/DMIBAR
Address Offset: 2C–2Fh
Reset Value: 02000000h
Access: RO, RW
Size: 32 bits
BIOS Optimal Default 00000h
Bit Access
Reset
Value
RST/
PWR
Description
31 RW 0b Uncore
Virtual Channel private Enable (VCPE)
0 = Virtual Channel is disabled.
1 = Virtual Channel is enabled. See exceptions below.
Software must use the VC Negotiation Pending bit to check
whether the VC negotiation is complete. When VC Negotiation
Pending bit is cleared, a 1 read from this VC Enable bit indicates
that the VC is enabled (Flow Control Initialization is completed for
the PCI Express port). A 0 read from this bit indicates that the
Virtual Channel is currently disabled.
BIOS Requirement:
1. To enable a Virtual Channel, the VC Enable bits for that
Virtual Channel must be set in both Components on a Link.
2. To disable a Virtual Channel, the VC Enable bits for that
Virtual Channel must be cleared in both Components on a
Link.
3. Software must ensure that no traffic is using a Virtual
Channel at the time it is disabled.
4. Software must fully disable a Virtual Channel in both
Components on a Link before re-enabling the Virtual
Channel.
30:27 RO 0h Reserved (RSVD)
26:24 RW 010b Uncore
Virtual Channel private ID (VCPID)
This field assigns a VC ID to the VC resource. This field cannot be
modified when the VC is already enabled.
23:8 RO 0h Reserved (RSVD)
7RO 0bUncoreTraffic Class m / Virtual Channel private Map (TCMVCPM)
6:1 RW 00h Uncore
Traffic Class / Virtual Channel private Map (TCVCPM)
It is recommended that private TC6 (01000000b) is the only
value that should be programmed into this field for VCp traffic
which will be translated by a virtualization engine, and TC2
(00000010b) is the only value that should be programmed into
this field for VCp traffic which will not be translated by a
virtualization engine. This strategy can simplify debug and limit
validation permutations.
BIOS Requirement: Program this field with the value 100010b,
which maps TC2 and TC6 to VCp.
0RO 0bUncoreTc0 VCp Map (TC0VCPM)