The timekeeping doesn't depend on HZ value in presence of fine grained
clocksource and hence there should not be any time drift because of HZ
value which was chosen to be divisor of 32768.
OMAP has been using HZ = 128 value to avoid any time drift issues
because of 32768 HZ clock. But with various measurements performed
with HZ = 100, no time drift is observed and it also proves the
point about HZ not having impact on time keeping on OMAP.
Very informative thread on this topic is here:
https://lkml.org/lkml/2013/1/29/435
Special thanks to John Stulz, Arnd Bergmann and Russell King for their
valuable suggestions.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Create the headers needed for compiling under
mach-omap1/include/mach and mach-omap2/include/mach.
This was done with the following script:
#!/bin/bash
mach_files="clkdev.h gpio.h hardware.h io.h irqs.h memory.h \
smp.h system.h timex.h uncompress.h vmalloc.h"
omaps="mach-omap1 mach-omap2"
mach_dir_old="arch/arm/plat-omap/include/mach"
plat_dir_new="arch/arm/plat-omap/include/plat"
mkdir -p $plat_dir_new
git add $plat_dir_new
for dir in $omaps; do
mach_dir_new="arch/arm/$dir/include/mach"
for header in $mach_files; do
file="$mach_dir_new/$header"
if [ ! -f $file ]; then
echo -ne "/*\n * $file\n */\n\n#include <plat/$header>\n" > $file
git add $file
if [ ! -f $plat_dir_new/$header ]; then
git mv $mach_dir_old/$header $plat_dir_new/$header
fi
fi
done
done
Signed-off-by: Tony Lindgren <tony@atomide.com>