Messages in this thread | | | Date | Fri, 12 Sep 2014 09:23:24 +0200 | From | Sebastian Andrzej Siewior <> | Subject | Re: [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround for AM33xx |
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On 09/11/2014 07:04 PM, Frans Klaver wrote: > On 11 September 2014 18:04:32 CEST, Sebastian Andrzej Siewior <bigeasy@linutronix.de> wrote: >> On 09/11/2014 05:11 PM, Frans Klaver wrote: >> >>> I can still reproduce it on am335x. I can get out of it as soon as >>> something else gets written to the console though. >>> >>> # echo "<3>something" >/dev/kmsg >> >> Is this to stall it or to get out of it? > > This is to get out of it. I do this from an ssh connection after the console got stuck. The 3 kind of ensures the message is actually sent to ttyS0.
Interesting. This shouldn't do anything. If there is a TX operation in progress then ->start_tx() will simply return and the xmit buffer will be send once the current TX operation completes.
Is there anything I can do to reproduce this behavior? This problem only pops-up if you use DMA. With disabled DMA you don't see this, right?
Sebastian
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