[coreboot] P state generator for powernow

Rudolf Marek r.marek at assembler.cz
Sun Dec 28 09:29:47 CET 2008

Carl-Daniel Hailfinger wrote:
> Hi Rudolf,
> On 25.12.2008 22:08, Rudolf Marek wrote:
>> Hello,
>> I just fixed the generator. Now It generates right P-state tables for
>> revF of k8 CPUs. I just implemented correct TDP estimations.
> The generator didn't compile until I added a cpuid() function.

Yes the cpuid.c was included in March ;) Sorry I forgot to add that.

>> The program generates a ACPI ASL code which can be include in DSDT. It
>> provides p-state info for powernow-k8 driver and windows driver.
> I have attached the result of your code and what the proprietary BIOS
> does and the fixed^Whacked-up genpowernow.c file.
> The 1600 MHz step seems to be missing completely with the proprietary
> BIOS. A few other differences exist as well. I'm not sure whether the
> proprietary BIOS is right.

The differences are in PLL lock times etc. Check the the BKDG for details of 
that field. I think I used recommended.

Now we must investigate if the algorithm is correct. Please check the function 
and algorithm described in BKDG.

But I'm quite happy with the result, the power estimation works ;) and we have
same start/stop FID/VID ;)


More information about the coreboot mailing list