MCHBAR Registers
R
80
Intel
®
82925X/82925XE MCH Datasheet
Address
Offset
Register
Symbol
Register Name
Default
Value
Access
195–19Fh —
Reserved
—
—
1A0–1A3h
C1DRC0
Channel B DRAM Controller Mode 0
00000000h
R/W, RO
1A4–F0Fh — Reserved
—
—
F10–F13h
PMCFG
Power Management Configuration
00000000h
R/W
F14h
PMSTS
Power Management Status
00000000h
R/W/C/S
5.1
MCHBAR Register Details
5.1.1
C0DRB0—Channel A DRAM Rank Boundary Address 0
MMIO Range:
MCHBAR
Address Offset:
100h
Default Value:
00h
Access: R/W
Size: 8
bits
The
DRAM Rank Boundary Register
defines the upper boundary address of each DRAM rank
with a granularity of 32 MB. Each rank has its own single-byte
DRB
register. These registers are
used to determine which chip select will be active for a given address.
Channel and Rank Map:
Channel A Rank 0:
100h
Channel A Rank 1:
101h
Channel A Rank 2:
102h
Channel A Rank 3:
103h
Channel B Rank 0:
180h
Channel B Rank 1:
181h
Channel B Rank 2:
182h
Channel B Rank 3:
183h
Single Channel or Asymmetric Channels Example
If the channels are independent, addresses in Channel B should begin where addresses in Channel
A left off, and the address of the first rank of Channel A can be calculated from the technology
(256 Mbit, 512 Mbit, or 1 Gbit) and the x8 or x16 configuration. With independent channels, a
value of 01h in
C0DRB0
indicates that 32 MB of DRAM has been populated in the first rank, and
the top address in that rank is 32 MB.
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...