Power Management: Setting P-Limit is unsupported on this system

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Sep 22, 2014
supermicro x9dai
2*E5-2630 V2
GTX 760
Hi, I am working on a dual socket AS Rock EP2C602 mother board with 2* E5-2667 v2 processors and I am pretty close.

I cleaned up the DSDT removing SCK2 and SCK3 and fixing the processor ids for SCK0 and SCK1 (the first couple of each socket were set to 0x8x so I renumbered the exisiting processor ids from 00 to 0F and 10 to 1F and masked the out of range ones with 0x8x and 0x9x) and fixed up field sizes etc.

I generated 2 SSDTs using ssdtprgen one ssdt overrides -cpus 2 -logical 32 and the other just overrides -cpus 2 (which made 64 logical processors which seems like a bug). Note I fixed the processor definition in ssdtprgen which had the wrong number of cores specified for the processor.

I am booting clover with -xcpm_ipi.

With the SSDT that was built with -cpus 2 the system will boot but with no power management every core runs at 3.3 Ghz
The other SSDT with the logical override starts up the powermanagement but panics with "Setting P-Limit is unsupported on this system"

I have read the few posts about similar errors and have tried e.g removing _DSM from the "logical" SSDT, it would boot but PM didn't start. I am hoping to avoid using NullCPUPM and msr199 if possible.

Any pointers would be gladly received :)
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