Re: OMAP4430 /Pandaboard using RT_PREEMPT - Experience?
Am Fri, 22 Jun 2012 02:26:53 -0700 schrieb Emmanuel Deloget:
> The image successfully booted on my Pandabaord ES and on a friend's
> Pandaboard. I guess that more recent kernels (with more recent RT
> patches) also boots, as there is a very limited activity on the RT patch
> itself - and recent kernels seems to boot quite easily on any
> Pandaboard. I will probably check 3.4 + rt in the coming weeks.
Thanks for you informations!
I tried following setup:
- Kernel: 3.4.4
- RT-Patch: 3.4.4-rt13
# uname -a
Linux pdev 3.4.4-rt13 #1 SMP PREEMPT RT Thu Jun 28 11:34:25 CEST 2012
armv7l armv7l armv7l GNU/Linux
# cyclictest -t1 -p 80 -i 500 -l 10000000000
policy: fifo: loadavg: 64.78 68.71 68.55 3/214 4153
Min: 52 Act: 84 Avg: 85 Max: 5014
(around 7656995 cycles under heavy CPU and I/O-Load. Burnt my fingers
touching the chip)
The worst case jitter increases about 5000uS if I start write/read
operations onto the SD-Card. Is this phenomena known out there? I disabled
all powersaving settings in the kernel, also the the high precision timer
(not this 32KHz thing) is being used.