AMD SB600 - Manual (Page 40)

©2008 Advanced Micro Devices, Inc. SATA Registers (Device 18, Function 0)
AMD SB600 Register Reference Manual Proprietary Page 40
Port-N Serial ATA Control – RW – 32 bits [Mem_reg: ABAR + port offset + 2Ch]
Field Name Bits Default Description
Interface Power
Management Transitions
Allowed (IPM) 11:8 0h
Indicates which power states the HBA is allowed to transition
to. If an interface power management state is disabled, the
HBA is not allowed to initiate that state and the HBA must
PMNAK
P
any request from the device to enter that state.
0h No interface restrictions
1h Transitions to the Partial state disabled
2h Transitions to the Slumber state disabled
3h Transitions to both Partial and Slumber states
disabled
All other values reserved
Select Power
Management (SPM) 15:12 0h Read Only
Port Multiplier Port
(PMP) 19:16 0h Read Only
Reserved 31:20 Reserved