lkml.org 
[lkml]   [2020]   [Sep]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: canfdtest on flexcan loopback
From
Date
On 9/16/20 1:04 PM, Vladimir Oltean wrote:
> [ resending, forgot to copy Wolfgang ]
>
> On Wed 9/2/2020 10:09 AM, Wolfgang Grandegger wrote:
>> canfdtest normally runs on the DUT *and* a the host. The DUT receives
>> the messages from the host, increments the frame data bytes and then
>> sends them back to the host. With "loopback" mode, the data bytes are
>> not incremented and that's what you see above.
>>
>> Wolfgang
>
> Wolfgang is of course right, but we're nonetheless investigating what
> seems to be a real problem, and what Pankaj had seen was a red herring.
>
> So currently what I suspect is going on, when I am running canfdtest
> between 2 LS1028A-RDB boards, is that the DUT is reordering frames on
> TX.
>
> See, for example, the screenshot below:
> https://drive.google.com/file/d/1rOeW3aXh3kPh1CJ39lCccRfjFz5JN5I6/view?usp=sharing
>
> I have added trace points to the end of the flexcan_start_xmit function,
> which print the entire skb, and the frames appear to be written to the
> TX message buffer in the correct order. They are seen, however, in the
> incorrect order on the wire.

Which driver are you using? The mainline driver only uses one TX buffer.

Marc

--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |

[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2020-09-16 22:59    [W:0.109 / U:1.424 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site