From: Dmitry Torokhov <dtor_core@ameritech.net>
To: linux-kernel@vger.kernel.org
Subject: Question: monolitic_clock, timer_{tsc,hpet} and CPUFREQ
Date: Thu, 4 Sep 2003 22:14:24 -0500
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I noticed that although timer_tsc registers cpufreq notifier to detect
frequency changes and adjust cpu_khz it does not set cyc2ns_scale. Is
monotonic clocks supposed to be also accurate?

Will something like this suffice for timer_tsc (compiled, not yet booted):

--- 2.6.0-test4/arch/i386/kernel/timers/timer_tsc.c	2003-08-26 21:56:19.000000000 -0500
+++ linux-2.6.0-test4/arch/i386/kernel/timers/timer_tsc.c	2003-09-04 22:08:27.000000000 -0500
@@ -315,6 +315,7 @@
 		if (use_tsc) {
 			fast_gettimeoffset_quotient = cpufreq_scale(fast_gettimeoffset_ref, freq->new, ref_freq);
 			cpu_khz = cpufreq_scale(cpu_khz_ref, ref_freq, freq->new);
+			set_cyc2ns_scale(cpu_khz/1000);
 		}
 #endif
 	}
-
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