82801FB Datasheet, PDF (685/786 Pages) Intel Corporation – Intel I/O Controller Hub 6 (ICH6) Family

PCI Express* Configuration Registers
19.1.15
MBL—Memory Base and Limit Register
(PCI Express—D28:F0/F1/F2/F3)
Address Offset: 20–23h
Default Value: 00000000h
Attribute:
Size:
R/W
32 bits
Accesses that are within the ranges specified in this register will be sent to the attached device if
CMD.MSE (D28:F0/F1/F2/F3:04:bit 1) is set. Accesses from the attached device that are outside
the ranges specified will be forwarded to the backbone if CMD.BME (D28:F0/F1/F2/F3:04:bit 2)
is set. The comparison performed is MB ≥ AD[31:20] ≤ ML.
Bit
Description
31:20
19:16
15:4
3:0
Memory Limit (ML) — R/W. These bits are compared with bits 31:20 of the incoming address to
determine the upper 1-MB aligned value of the range.
Reserved
Memory Base (MB) — R/W. These bits are compared with bits 31:20 of the incoming address to
determine the lower 1-MB aligned value of the range.
Reserved
19.1.16
PMBL—Prefetchable Memory Base and Limit Register
(PCI Express—D28:F0/F1/F2/F3)
Address Offset: 24–27h
Default Value: 00010001h
Attribute:
Size:
R/W, RO
32 bits
Accesses that are within the ranges specified in this register will be sent to the device if CMD.MSE
(D28:F0/F1/F2/F3;04, bit 1) is set. Accesses from the device that are outside the ranges specified
will be forwarded to the backbone if CMD.BME (D28:F0/F1/F2/F3;04, bit 2) is set. The
comparison performed is PMBU32:PMB ≥ AD[63:32]:AD[31:20] ≤ PMLU32:PML.
Bit
Description
31:20
Prefetchable Memory Limit (PML) — R/W. These bits are compared with bits 31:20 of the
incoming address to determine the upper 1-MB aligned value of the range.
19:16
15:4
3:0
64-bit Indicator (I64L) — RO. This field indicates support for 64-bit addressing
Prefetchable Memory Base (PMB) — R/W. These bits are compared with bits 31:20 of the
incoming address to determine the lower 1-MB aligned value of the range.
64-bit Indicator (I64B) — RO. This field indicates support for 64-bit addressing
Intel^® I/O Controller Hub 6 (ICH6) Family Datasheet
685