i.MX Processors中的主题 Real Time Linux on iMX28

Real Time Linux on iMX28

tty — Sun, 04 Sep 2011 18:49:03 GMT

Anyone made the i.mx28 Linux kernel a real time?
Regards.

Re: Real Time Linux on iMX28

fabio_estevam — Sun, 04 Sep 2011 20:20:42 GMT

Real Time patches are available at:

http://www.kernel.org/pub/linux/kernel/projects/rt/

MX28EVK is supported in the mainline kernel, so you can try it running RT on a 3.0 kernel.

Regards,

Fabio Estevam

Re: Real Time Linux on iMX28

tty — Thu, 22 Sep 2011 09:15:30 GMT

Thanks, Fabio.

I tried a 3.0.4 kernel with a patch-3.0.4-rt14. But I got bad results, I think. Cyclictests result:

/usr/local/bin/cyclictest -a -n -m -p99
policy: fifo: loadavg: 15.67 16.92 15.62 18/69 4270

T: 0 ( 8894) P:99 I:1000 C:2209243 Min: 31 Act: 125 Avg: 115 Max: 656

/usr/local/bin/cyclictest -a -n -m -p99

This test has much better result on imx27(https://www.osadl.org/Latency-plot-of-system-in-rack-2-slot.qa-latencyplot-r2s1.0.html), but with 2.6.33 kernel.

Fabio Estevam said:

Real Time patches are available at:
http://www.kernel.org/pub/linux/kernel/projects/rt/

MX28EVK is supported in the mainline kernel, so you can try it running RT on a 3.0 kernel.

Regards,

Fabio Estevam

Re: Real Time Linux on iMX28

fabio_estevam — Thu, 22 Sep 2011 12:38:46 GMT

I am not familiar with the cyclictest, but maybe one element that can explain the better performane on MX27 is due to the 32bit DDR interface versus 16bit DDR on MX28.

Regards,

Fabio Estevam

Re: Real Time Linux on iMX28

awdenx — Wed, 03 Oct 2012 19:12:22 GMT

Xenomai supports i.MX28. Please see

http://git.xenomai.org/?p=ipipe-gch.git;a=commit;h=c7ebf99824fe8160f562194e87822a0a32870ba5

Regards

Andreas

Re: Real Time Linux on iMX28

cono — Mon, 08 Jul 2013 12:56:59 GMT

Hi,

the timer initialization used by iMX28 is not correct as discussed here:

http://list-archives.org/2012/12/21/linux-kernel-vger-kernel-org/improve-timer-resolution-on-imx28/f/2814370744

With this fix I got worsed case latency times about 210us.

Regards

Christoph