ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock
authorNicolas Pitre <nicolas.pitre@linaro.org>
Mon, 18 Feb 2013 15:36:13 +0000 (16:36 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Thu, 21 Feb 2013 13:25:36 +0000 (13:25 +0000)
commit70264367a243a68b1d5636ffb570183449803cbe
treed5ab3e7434c916f97b2e22fee6dd48c7cc9c416c
parent7c4e9ced424be4d36df6a3e3825763e97ee97607
ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock

When udelay() is implemented using an architected timer, it is wrong
to scale loops_per_jiffy when changing the CPU clock frequency since
the timer clock remains constant.

The lpj should probably become an implementation detail relevant to
the CPU loop based delay routine only and more confined to it. In the
mean time this is the minimal fix needed to have expected delays with
the timer based implementation when cpufreq is also in use.

Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/include/asm/delay.h
arch/arm/kernel/smp.c
arch/arm/lib/delay.c