[PATCH 09/16] tty: serial: 8250_dma: Add a TX trigger workaround for AM33xx

Frans Klaver frans.klaver at xsens.com
Mon Sep 29 01:50:42 PDT 2014

On Thu, Sep 25, 2014 at 05:14:03PM +0200, Sebastian Andrzej Siewior wrote:
> * Frans Klaver | 2014-09-22 11:28:54 [+0200]:
> >I guess then we'd still have to answer the question why the yocto build
> >calls set_termios() so often, but that's not on you then. Did you notice
> >it even changing settings? We might want to fix this even if the kernel
> >should be able to cope.
> could you please test uart_v10_pre3? I dropped a few register sets and
> delayed the register update until TX-DMA is complete. I am traveling
> currently and have only my boneblack and it passes my limited testing.
> If it solves your problems, too then I would address Heikki's latest
> comments and prepare the final v10 (and I hope I didn't break beagle
> board in between).

This version fixes the console things for us. It also increases the
amount of data we can push over the serial port. If I push the data
towards our requirements, we're not there yet. I get the "too much work
for irq" notice still. However, I don't think you'd need to be fixing
that in this series (or at all). We had similar issues there with
omap-serial as well.

As far as I'm concerned, this is

Tested-by: Frans Klaver <frans.klaver at xsens.com>


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