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

[Dominik Brodowski <linux@brodo.de>]

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 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.

> 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 very much would like to have a way to override (or add to) the bios provided
> values.

AFAIK, Dave Jones will add support to override the BIOS-provided tables.

>  --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++;