From mboxrd@z Thu Jan  1 00:00:00 1970
From: Frans Klaver <frans.klaver@xsens.com>
Subject: Re: [PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround
 for AM33xx
Date: Mon, 29 Sep 2014 12:30:43 +0200
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To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>, Peter Hurley <peter@hurleysoftware.com>, tony@atomide.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, balbi@ti.com, linux-serial@vger.kernel.org, linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Alan Cox <alan@linux.intel.com>

On Mon, Sep 29, 2014 at 11:54:40AM +0200, Sebastian Andrzej Siewior wrote:
> There is a patch named "ARM: edma: unconditionally ack the error
> interrupt". I have the feeling that this is not really required once we
> delay set_termios. I couldn't reproduce the bug with beagleblack with my
> usual test case.

I think so too. I didn't need it either.


> For your "too much work for irq" problem: Could you add trace_printk()
> in tx/rx dma start/complete, and irq routine? The interresting part is
> what is the irq routine doing once entered. It might be a condition that
> is ignored at first and "acked" later while serving another event. Or it
> is really doing something and this is more or less "legal".

I'll have a look at that.

> 
> >Thanks,
> >Frans
> 
> Sebastian