From: Bhavana Nagendra <bnagendr@redhat.com>
Subject: [RHEL5.1 PATCH] Support mobile processors in fid/did to frequency 	conversion
Date: Mon, 6 Aug 2007 11:30:42 -0400
Bugzilla: 250833
Message-Id: <20070806152801.15742.41087.sendpatchset@allegro.boston.redhat.com>
Changelog: [x86] Support mobile processors in fid/did to frequency conversion


Resolves BZ 250833

This patch makes the frequency calculation family dependant, to ensure the 
frequency reported by the mobile processor in the _PSS objects matches the 
frequencies the kernel can identify. Otherwise the driver assumes that the
ACPI data is bad and Power Now! will not function on the mobile processors.

Further, only processors that use the hardware p-state driver have fid/did;
family 0xf processors (K8) use fid/vid.  In otherwords this change does not
affect the dual core K8 processor code path.

Patch applies to -36.el5 cleanly, here is the brew build.
http://brewweb.devel.redhat.com/brew/taskinfo?taskID=907955
 
Patch tested on mobile platform by AMD.

The patch has been submitted to Dave Jones on the cpufreq mailing list.
 
--- linux-2.6.18.x86_64/arch/i386/kernel/cpu/cpufreq/powernow-k8.c.didorig	2007-08-06 08:13:11.000000000 -0400
+++ linux-2.6.18.x86_64/arch/i386/kernel/cpu/cpufreq/powernow-k8.c	2007-08-06 08:16:40.000000000 -0400
@@ -79,7 +79,10 @@ static u32 find_khz_freq_from_fid(u32 fi
 /* Return a frequency in MHz, given an input fid and did */
 static u32 find_freq_from_fiddid(u32 fid, u32 did)
 {
-	return 100 * (fid + 0x10) >> did;
+	if (current_cpu_data.x86 == 0x10)
+		return 100 * (fid + 0x10) >> did;
+	else
+		return 100 * (fid + 0x8) >> did;
 }
 
 static u32 find_khz_freq_from_fiddid(u32 fid, u32 did)