Dear Sir,
I have recently acquired a ts-7500 board with the development kit. The SD card comes with a 2.6.24 Linux Kernel. After a few days of experimenting I have realized that my application (controlling a servo through PWM) will require HRT and RT support which the Kernel is unable to provide (maximum timer resolution I am getting on the current Kernel is 20ms).
I am new to Linux and embedded systems development and hence I am a little confused about how to tackle this problem. I do not understand what you mean by applying the patches and how to apply the patch. Can i simply do it on-board my board with the SD-Card. I have a windows PC with Eclipse for Development.
Any help you can provide me will be highly appreciated. Thank you.
Regards,
Komal RAUF
--- In
, Peter Gammie <> wrote:
>
> Charles, any anyone interested in hrtimers:
>
> With Andrew's help I managed to build a 2.6.32.3 kernel that seems to work. Attached are a config and a patch, based on this:
>
> http://lkml.org/lkml/2009/7/22/119
>
> that enable hrtimers. I've lightly tested it on a ts7260 with 64Mb of memory. I loaded the kernel via TFTP with:
>
> load -r -b 0x00218000 -h 192.168.1.1 z
> exec -c "console=ttyAM0,115200 ip=192.168.1.50:192.168.1.1:192.168.1.1:255.255.255.0:ts7200a:eth0:off root=/dev/mtdblock1"
>
> (i.e. no special memory options or anything.)
>
> So the routine is to apply Matthieu's patches, then this one. I expect it will apply to other kernel versions (specifically 2.6.29.6 if you want -RT) without too much bother - but be careful that the Kconfig patch applies to the right system type!
>
> As for the clock multiplexing, Charles's suggestion of using just a PREEMPT (not RT) kernel results in better behaviour under light periodic load (it doesn't flicker while running top on the console) but about the same under heavier load (scp'ing a few megabytes via ethernet). I have the CONFIG_NO_HZ (tickless) option set, which may or may not do anything in particular...
>
> So, more investigation is required.
>
> Thanks for all your help.
>
> cheers
> peter
>
>
>
>
> --
> http://peteg.org/
>