amd64/189267: AMD Kabini (AM1/FM1Sb) Frequency Switching Causes Crash

[Brodey Dover]

>Number:         189267
>Category:       amd64
>Synopsis:       AMD Kabini (AM1/FM1Sb) Frequency Switching Causes Crash
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri May 02 22:00:00 UTC 2014
>Closed-Date:
>Last-Modified:
>Originator:     Brodey Dover
>Release:        9.2-RELEASE-p4
>Organization:
>Environment:
FreeBSD freenas.brodeydover.ca 9.2-RELEASE-p4 FreeBSD 9.2-RELEASE-p4 #0 r262572+
17a4d3d: Wed Apr 23 10:09:38 PDT 2014     root at build3.ixsystems.com:/tank/home/j
kh/build/9.2.1/freenas/os-base/amd64/fusion/jkh/9.2.1/freenas/FreeBSD/src/sys/FR
EENAS.amd64  amd64
>Description:
Running powerd on FreeNAS system with C6 state enabled in BIOS causes the system to crash shortly after start-up. Disabling the C6 state in the BIOS resolves the system crashing but then one does not receive the low power modes afforded by the platform. 

Disabling powerd, however, enabling CnQ and C6 state in the BIOS also resolves the system crashing with the same effect; no low power modes. I also note significant power usage from a system that should otherwise be consuming less power than my Skt 939 90W TDP X2 3800+ with 4x DDR 1GB modules. I noted that the GPU was also never down-clocked and would never enter any low power modes.

I feel that this is a serious compatibility issue for hardware (that I think was released when 9.2 was production). 
>How-To-Repeat:
Run hardware on FreeBSD 9.2. (I haven't tried FreeBSD 10).
>Fix:
N/A

>Release-Note:
>Audit-Trail:
>Unformatted: