From mboxrd@z Thu Jan 1 00:00:00 1970 From: Felix Braun Subject: [PATCH 2.6.14] cpufreq: don't suggest speedstep-centrino for Dothan-based Celeron-M processors Date: Fri, 2 Dec 2005 14:57:11 +0100 Message-ID: <20051202145711.33191cef@tilion.getrex.org> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: cpufreq-bounces@lists.linux.org.uk Errors-To: cpufreq-bounces+glkc-cpufreq=gmane.org+glkc-cpufreq=gmane.org@lists.linux.org.uk Content-Type: text/plain; charset="us-ascii" To: CPUFreq@lists.linux.org.uk Hi there, I recently bought a laptop which is reported by Intel's CPUid tool as a Celeron-M 373. Linux identifies this processor like this (/proc/cpuinfo) processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 13 model name : Intel(R) Celeron(R) M processor 1.00GHz stepping : 8 cpu MHz : 999.915 cache size : 512 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss tm pbe bogomips : 2001.80 I would like to use CPU frequency scaling to increase my battery life. As this processor can't do EnhancedSpeedStep (Celerons seem to be unable to do so in general) I've been using the p4-clockmod driver. However, as my processor is based on the Dothan architecture (cpu_family 6, model 13), I get a warning that I should use speedstep_centrino instead. This warning is misleading because I have a Celeron. Therefore, I suggest the following patch to silence this warning. ================ We only have a Pentium-M (Dothan) if the cache size is 2048K. Don't print the warning for Dothan-based Celeron-M processors which have a cache size of 512K or 1024K. Signed-off-by: Felix Braun --- a/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c 2005-12-01 23:47:01 +0100 +++ b/arch/i386/kernel/cpu/cpufreq/p4-clockmod.c 2005-12-01 23:50:11 +0100 @@ -171,7 +171,8 @@ return speedstep_get_processor_frequency(SPEEDSTEP_PROCESSOR_PM); } - if ((c->x86 == 0x06) && (c->x86_model == 0x0D)) { + if ((c->x86 == 0x06) && (c->x86_model == 0x0D) + && (c->x86_cache_size == 2048)) { /* Pentium M (Dothan) */ printk(KERN_WARNING PFX "Warning: Pentium M detected. " "The speedstep_centrino module offers voltage scaling"