Specification Sheet
Datasheet, Volume 2 of 2 267
GFXVTBAR Registers
8.3 Extended Capability Register (ECAP)—Offset 10h
Register to report remapping hardware extended capabilities
Access Method
Default: 7E3FF0505Eh
4
0h
RO
RWBF:
0: Indicates no write-buffer flushing is needed to ensure changes to memory-resident
structures are visible to hardware.
1: Indicates software should explicitly flush the write buffers to ensure updates made
to memory-resident remapping structures are visible to hardware.
3
0h
RO
AFL:
0: Indicates advanced fault logging is not supported. Only primary fault logging is
supported.
1: Indicates advanced fault logging is supported.
2:0
2h
RO
ND:
000b: Hardware supports 4-bit domain-ids with support for up to 16 domains.
001b: Hardware supports 6-bit domain-ids with support for up to 64 domains.
010b: Hardware supports 8-bit domain-ids with support for up to 256 domains.
011b: Hardware supports 10-bit domain-ids with support for up to 1024 domains.
100b: Hardware supports 12-bit domain-ids with support for up to 4K domains.
100b: Hardware supports 14-bit domain-ids with support for up to 16K domains.
110b: Hardware supports 16-bit domain-ids with support for up to 64K domains.
111b: Reserved.
Bit
Range
Default &
Access
Field Name (ID): Description
Type: MEM
(Size: 64 bits)
Offset: [B:0, D:0, F:0] + 10h
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
1
1
1
1
1
1
0
0
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
1
0
1
0
0
0
0
0
1
0
1
1
1
1
0
RSVD
PSS
EAFS
NWFS
POT
SRS
ERS
PRS
PASID
DIS
NEST
MTS
ECS
MHMV
RSVD
IRO
SC
PT
RSVD
EIM
IR
DT
QI
C
Bit
Range
Default &
Access
Field Name (ID): Description
63:41
0h
RO
Reserved (RSVD): Reserved.
40
1h
ROV
PASID:
0: Hardware does not support process address space IDs.
1: Hardware supports Process Address Space IDs.
39:35
Fh
RO
PSS: This field reports the PASID size supported by the remapping hardware for
requests with- PASID. A value of N in this field indicates hardware supports PASID field
of N+1 bits (For example, value of 7 in this field, indicates 8-bit PASIDs are
supported). Requests-with-PASID with PASID value beyond the limit specified by this
field are treated as error by the remapping hardware. This field is valid only when
PASID field is reported as Set.