Host-PCI Express* Graphics Bridge Registers (D1:F0)
R
138
Intel
®
82925X/82925XE MCH Datasheet
8.1.36
LCAP—Link Capabilities (D1:F0)
PCI Device:
1
Address Offset:
ACh
Default Value:
02012E01h
Access: R/WO
Size: 16
bits
This register indicates PCI Express device specific capabilities.
Bit Access
&
Default
Description
31:24 RO
02h
Port Number:
This field indicates the PCI Express* port number for the given PCI
Express link. This field matches the value in Element Self Description [31:24].
23:18
Reserved
17:15 R/WO
010b
L1 Exit Latency:
This field indicates the length of time this Port requires to
complete the transition from L1 to L0. The value 010 b indicates the range of 2 µs
to less than 4 µs. If this field is required to be any value other than the default,
BIOS must initialize it accordingly.
Both bytes of this register that contain a portion of this field must be written
simultaneously in order to prevent an intermediate (and undesired) value from
ever existing.
14:12 R/WO
010b
L0s Exit Latency:
This field indicates the length of time this Port requires to
complete the transition from L0s to L0. The value 010 b indicates the range of 128
ns to less than 256 ns. If this field is required to be any value other than the
default, BIOS must initialize it accordingly.
Note:
When PCI Express* is operating with separate reference clocks, L0s exit
latency may be greater than the setting in the L0s Exit Latency Register. Expect
longer exit latency then setting in L0s Exit Latency Register. The link may enter
Recovery state before reaching L0. System BIOS can program the appropriate
Exit Latency and advertised N_FTS value if it detects that the downstream device
is not using the common reference clock (indicated in the Slot Clock Configuration
bit 12 of the device’s Link Status Register)
11:10 R/WO
11b
Active State Link PM Support:
L0s and L1 entry supported.
9:4 RO
10h
Max Link Width:
Hardwired to indicate X16.
When Force X1 mode is enabled on this PCI Express* x16 Graphics Interface
device, this field reflects X1 (01h).
3:0 RO
1h
Max Link Speed:
Hardwired to indicate 2.5 Gb/s.
Содержание 82925X
Страница 78: ...Host Bridge DRAM Controller Registers D0 F0 R 78 Intel 82925X 82925XE MCH Datasheet...
Страница 98: ...EPBAR Registers Egress Port Register Summary R 98 Intel 82925X 82925XE MCH Datasheet...
Страница 108: ...DMIBAR Registers Direct Media Interface DMI RCRB R 108 Intel 82925X 82925XE MCH Datasheet...
Страница 156: ...Host PCI Express Graphics Bridge Registers D1 F0 R 156 Intel 82925X 82925XE MCH Datasheet...
Страница 172: ...System Address Map R 172 Intel 82925X 82925XE MCH Datasheet...
Страница 192: ...Electrical Characteristics R 192 Intel 82925X 82925XE MCH Datasheet...
Страница 220: ...Ballout and Package Information R 220 Intel 82925X 82925XE MCH Datasheet Figure 12 3 MCH Package Dimensions MCH...