Specifications

© 2008 Advanced Micro Devices Inc.
SB600 Early-POST Initialization
AMD SB600 BIOS Developer’s Guide (Public Version) Proprietary
Page 19
3.5 SubSystemID and SubSystem Vendor ID
SubSytem ID and SubSystem Vendor ID can be programmed in various functions of SB600
register 2Ch. These registers are write-once registers. For example, to program a SubSystem
vendor ID of 1002h and SubSystem ID of 4341h in AC97 device 14h, function 5, use the
following assembly language sample code:
mov eax,8000A52Ch
mov dx,0CF8h
out dx,eax
mov dx,0CFCh
mov eax,43411002h
out dx,eax
3.6 AMD Athlon™ Processor Registers
The SB600 is set for the AMD Athlon processor by hardware strap. The following registers in the
PM IO space (accessed through index/data registers at CD6h/CD7h) are specific for the AMD
Athlon processor. For the early post initialization these registers may be left at default values.
SMAFx in the table below are sent with STPCLK messages down the HyperTransport™ link.
Register Name Default Description
PM IO 80h SMAF0 06h System Management Action for C2 and S4/S5
PM IO 81h SMAF1 21h System Management Action for VFID and C3
PM IO 82h SMAF2 43h System Management Action for S3 and S1
PM IO 83h SMAF3 55h System Management Action for thermal and normal
throttling.
PM IO 85h CF9Rst 00h Full reset/INIT
PM IO 86h Thermal Throttle
Control
00h Enables time control for thermal throttling.
PM IO 87h LdtStpCmd 00h Write bit[0] = 1 to generate C3
PM IO 88h LdtStartTime 00h LDTSTP# assertion delay in microseconds
PM IO 8Ah LdtAgpTimeCntl 00h LDTSTP# de-assertion delay select
PM IO 8Bh StutterTime 00h Stutter LDTSTP# duration in microseconds
PM IO 8Ch StpClkDlyTime 00h STPCLK# assertion in microseconds
PM IO 8Dh AbPmeCntl 0Eh Fake A-link bridge PME