Product specifications

CN333 Data Sheet
Revision 1.0, January 5, 2005 -53- Device 0 Function 3 Register Descriptions - DRAM
DRAM Above 4G Control
Offset 84 – Low Top Address Low (00h).........................RW
7-4 Low Top Address Low ............................ default = 0
3-0 DRAM Granularity
0 16M Total DRAM less than 4G.........default
1 32M Total DRAM less than 8G
2 64M Total DRAM less than 16G
3 128M Total DRAM less than 32G
4 256M Total DRAM less than 64G
5-7 -reserved-
Offset 85 – Low Top Address High (FFh).......................RW
7-0 Low Top Address High........................ default = FFh
Offset 86 – SMM / APIC Decoding (01h) ....................... RW
7-6 Reserved ........................................always reads 0
5 APIC Lowest Interrupt Arbitration
0 Disable................................................... default
1 Enable
4 I/O APIC Decoding
0 FECxxxxx accesses go to PCI............... default
1 FEC00000 to FEC7FFFF accesses go to PCI
FEC80000 to FECFFFFF accesses go to AGP
3 MSI (Processor Message) Support
0 Disable (master access to FEExxxxx will go to
PCI) .................................................... default
1 Enable (master access to FEExxxxx will be
passed to host side to do snoop)
2 Top SMM
0 Disable................................................... default
1 Enable
1 Reserved ........................................always reads 0
0 Compatible SMM
0 Disable
1 Enable................................................... default