1000 Hz is possible. I run it on my Bones.
Change can look something like this:
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f44d5a0..9469e1e 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1570,7 +1570,7 @@ config HZ
default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
default AT91_TIMER_HZ if ARCH_AT91
default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE
- default 100
+ default 1000
config THUMB2_KERNEL
bool "Compile the kernel in Thumb-2 mode (EXP
Check that it's true, providing you don't have a tickless system
(dynamic ticks), by watching jiffies count:
root@bone1:~# cat /proc/interrupts | grep gp && cat /proc/uptime
68: 173922 INTC gp timer
174.69 156.66
root@bone1:~# cat /proc/interrupts | grep gp && cat /proc/uptime
68: 529386 INTC gp timer
529.80 511.74
The uptime and the gp timer _should_ count up at a factor of about
1:1000 with a 1000Hz kernel.
I believe you can't just set this in the .config or defconfig file. The
kernel build system will override it, thus the diff above which changes
that default. There's probably a "more right" way to accomplish this,
but this is the easy one.
Disabling dynamic ticks and upping the Hz to 1000 should increase your
power consumption, so just be aware of that. Sitting idle isn't really
sitting idle when you do this.
I don't believe you can push beyond about 1200 or 1500 Hz, so be aware
of that. I'm sure it's possible, but it'll require more than just
changing one line :)
-Andrew