Re: [Xenomai] ODROID-U3 porting problems

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

On 08/27/2014 05:45 PM, Gilles Chanteperdrix wrote:
> On 08/27/2014 03:49 PM, GP Orcullo wrote:
>> Hi,
>>
>> I'm in the process of porting xenomai to Samsung Exynos 4420 based
>> ODROID-U3 board. I've followed the online manual and I was able to finish
>> up to the interrupt controller part.
>>
>> So far everything works when booting the board with CONFIG_IPIPE and
>> CONFIG_XENOMAI enabled. However, running the latency test gives the
>> following results:
>>
>> root@odroidu3:~# /usr/lib/xenomai/testsuite/latency -t 0 -T5
>> == Sampling period: 1000 us
>> == Test mode: periodic user-mode task
>> == All results in microseconds
>> warming up...
>> RTT|  00:00:01  (periodic user-mode task, 1000 us period, priority 99)
>> RTH|----lat min|----lat avg|----lat max|-overrun|---msw|---lat best|--lat worst
>> RTD|-1054607.854|-555107.854|-416666.667|       0|
>> 0|-1054607.854|-416666.667
>> RTD|-2054607.854|-1555107.854|-416666.667|       0|
>> 0|-2054607.854|-416666.667
>> RTD|1240359.443|1739859.443|-416666.667|       0|     0|1240359.443|-416666.667
>> RTD| 240359.443| 739859.443|-416666.667|       0|     0| 240359.443|-416666.667
>> ---|-----------|-----------|-----------|--------|------|-------------------------
>> RTS| 240359.443|-2055107.854|-416666.667|       0|     0|    00:00:05/00:00:05
> 
> I would say you have a problem with the tsc emulation. Have you tried to
> run the "tsc" program?

In fact, your problem is only with the user-space tsc emulation. Are you
sure you passed the right physical address of the counter used for tsc
emulation, in the structure passed to the ipipe_tsc_register service?
You do not seem to be using the global timer, since your counter has a
24 MHz frequency. Note that the global timer probably runs at 500 MHz on
your system, so using the global timer would yield a better precision.

-- 
                                                                Gilles.