[lm-sensors] wrong output with fam15h_power

[Lucas Stach]

Hi,

I'm trying to use the fam15h_power driver to measure my processors power
consumption, but it gives me clearly wrong values. With a completely
idle system the processor claims to be using 125261718µW, which would
mean the processor operates at it's TDP limit. With all cores 100%
loaded it claims to be using 130675781µW which I can't believe as this
would mean the processor violates it's own spec.

This is a desktop system with an AMD FX-8150 processor on a brand new
Gigabyte GA-970A-UD3 board with the latest (F4) BIOS.

Is this a known bug? If not I would be glad to help track this down. I
had a quick look at the BIOS and Kernel Developer’s Guide (BKDG) for AMD
Family 15h (#42301) but couldn't determine if the math done in the
fam15h_power driver is correct or if we need to set some registers to
specific values to make this work as intended. Any hints would be
appreciated.

Thanks,
Lucas