Re: [Xenomai] Support of Beagleboard xm rev C on 3.14-ipipe

[Arnaud Degroote <arnaud.degroote@isae.fr>]

On 03/Jul - 14:34, Gilles Chanteperdrix wrote:
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> On 07/03/2014 10:38 AM, Arnaud Degroote wrote:
> > On 02/Jul - 19:59, Gilles Chanteperdrix wrote:
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> >> 
> >> Well, this sucks, posted writes increase the timer programming
> >> latency.
> >> 
> >> Does the latency test run correctly with this patch?
> > 
> > Yes, the latency test seems to work properly.
> 
> That is strange, because the Xenomai timer also uses non-posted writes.
> 
> > 
> > I need to investigate a bit more, because the kernel without the
> > patch seems to work properly with a different uboot (the one for my
> > gumstix) while it hangs with the uboot for my beagleboard.
> 
> Perhaps the u-boot which works implement some workaround for processor
> errata, which the u-boot which does not work does not implement?

I don't understand where the difference comes from. I tried with
several variants of u-boot, with the same patchlevel, and it always
works with 'omap_overo_config' and always hangs with
'omap_beagle_config'. I carefully read the two board code and make
several hack in beagle one to reduce diff with overo, but was not able
yet to reproduce the 'correct behaviour'.

Unfortunately,  I lack time to continue investigation, I will go for the
'posted' hack for the moment and will open an issue in my job
bugtracker. I may try also with uboot + dts.

Anyway, thanks a lot for your help Gilles. I will let you know if I make
significant progress on this issue.

Best regards,
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