Re: 2.6.0-test1: CPUFreq not working, can't find sysfs interface

[textshell@neutronstar.dyndns.org]

On Tue, Jul 22, 2003 at 04:23:53PM +0200, Dominik Brodowski wrote:
> On Tue, Jul 22, 2003 at 04:18:39PM +0200, textshell@neutronstar.dyndns.org wrote:
> > So it seems to me that the BIOS doesn't have the tables for my Athlon
> > model/stepping. I tried to get a new bios from hp, but it didn't change anything
> > relevant (they changed something in the PSTs but did not add a new one for my
> > processor)
> 
> Indeed, that's the BUG().

I'll complain to HP about that.

> 
> > > I guess it's yet another BIOS problem... [as seen quite often wrt AMD
> > > PowerNow, unfortunately]
> > 
> > I think it would be a good thing to display a Message explaining why powernow
> > isn't working to the user in the case that no relevant PST is found.
> 
> Patch appended at the end.

Yes that patch would IMHO point users with broken BIOS tables in the right
direction.

> 
> > Can you suggest any workaround for this problem, or is my only option to
> > complain to HP do supply an updated BIOS. 
> 
> Well, you could try using the PST which mostly matches your system except
> the CPUID [PST #12, see below] -- if the values used are similar to the ones
> Windows XP uses. But this might be risky!!!
> 

I think you know a bit more about these matters than me, so please allow me this
question:
How much risk do you think that would be (with the usual 'you are not responible
for any damages' stuff as usual) to just use that entry? At with the performance
governour it is exactly the same as displayed as currently by x86info so that
shouldn't be a problem. Do you think that lower frequencies and voltages can
kill the processor? [I can cope with instabilities]

Thank you for your help.

Martin H.


> >  --DEBUG: 7a0 ?= 781 && 21 ?= 21, 11 ?= 11
> >  PST:12 (@0x4017d8dc)
> >   cpuid: 0x781	  fsb: 133	  maxFID: 0x15	  startvid: 0xb
> >   num of p states in this table: 6
> >     FID: 0x12 (4.0x [532MHz])	VID: 0x13 (1.200V)
> >     FID: 0x4 (5.0x [665MHz])	VID: 0x13 (1.200V)
> >     FID: 0x6 (6.0x [798MHz])	VID: 0x13 (1.200V)
> >     FID: 0x8 (7.0x [931MHz])	VID: 0x13 (1.200V)
> >     FID: 0xe (10.0x [1330MHz])	VID: 0xe (1.300V)
> >     FID: 0x15 (13.5x [1796MHz])	VID: 0xb (1.450V)
> 
> 	Dominik
> 
> diff -ruN linux-original/arch/i386/kernel/cpu/cpufreq/powernow-k7.c linux/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
> --- linux-original/arch/i386/kernel/cpu/cpufreq/powernow-k7.c	2003-07-11 14:12:35.000000000 +0200
> +++ linux/arch/i386/kernel/cpu/cpufreq/powernow-k7.c	2003-07-22 16:16:00.000000000 +0200
> @@ -345,6 +345,7 @@
>  						p+=2;
>  				}
>  			}
> +			dprintk (KERN_INFO PFX "Did not find any PST table for this CPU -- exiting\n");
>  			return -EINVAL;
>  		}
>  		p++;