Bug 9561

Summary: powernow-k8 cpuid c0f13 not supported w/ fx-74 CPUs
Product: Power Management Reporter: Dmitry Savchenko (blackprince2000)
Component: cpufreqAssignee: Mark Langsdorf (mark.langsdorf)
Status: CLOSED CODE_FIX    
Severity: low CC: lars.tobias.borsting
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.24-rc4-git6 Subsystem:
Regression: --- Bisected commit-id:
Attachments: x86info output
Patch to revise powernow xmod

Description Dmitry Savchenko 2007-12-14 09:45:13 UTC 
Most recent kernel where this bug did not occur: unknown
Distribution: gcc version 4.1.2 (Gentoo 4.1.2 p1.0.2)
Hardware Environment: 2xAMD Athlon FX-74 CPUs on ASUS L1N64-SLI WS NF680a 1207 MB
Software Environment: gentoo

Problem Description:
While trying to enable Cool'n'Quiet, dmesg error with:

powernow-k8: Processor cpuid c0f13 not supported
powernow-k8: Processor cpuid c0f13 not supported
powernow-k8: Processor cpuid c0f13 not supported
powernow-k8: Processor cpuid c0f13 not supported

Tried w/ powernow-k8 build as a module as well as build into kernel... same
result.

Steps to reproduce:
1. compile kernel with powernow-k8 support
2. boot on Athlon FX-74 CPU
Comment 1 Dmitry Savchenko 2007-12-14 09:47:43 UTC 
Created attachment 14038 [details]
x86info output
Comment 2 Mark Langsdorf 2007-12-14 10:08:53 UTC 
Looks like it should be pretty easy to fix.  Try this patch:

--- linux-2.6.23-git18-vanilla/arch/x86/kernel/cpu/cpufreq/powernow-k8.h.old	2007-12-14 12:15:06.000000000 -0600
+++ linux-2.6.23-git18-vanilla/arch/x86/kernel/cpu/cpufreq/powernow-k8.h	2007-12-14 12:15:27.000000000 -0600
@@ -47,7 +47,7 @@ struct powernow_k8_data {
 #define CPUID_XFAM			0x0ff00000	/* extended family */
 #define CPUID_XFAM_K8			0
 #define CPUID_XMOD			0x000f0000	/* extended model */
-#define CPUID_XMOD_REV_MASK		0x00080000
+#define CPUID_XMOD_REV_MASK		0x000c0000
 #define CPUID_XFAM_10H			0x00100000	/* family 0x10 */
 #define CPUID_USE_XFAM_XMOD		0x00000f00
 #define CPUID_GET_MAX_CAPABILITIES	0x80000000
Comment 3 Mark Langsdorf 2007-12-14 10:09:31 UTC 
Created attachment 14039 [details]
Patch to revise powernow xmod
Comment 4 Dmitry Savchenko 2007-12-14 10:35:29 UTC 
It fixed it for me.
thank you.