Re: [PATCH] serial: imx: disable DMA for RS-485 on i.MX6 SMP

From: Fabio Estevam
Date: Wed Jun 21 2017 - 10:12:30 EST

Hi Clemens,

On Wed, Jun 21, 2017 at 11:05 AM, Clemens Gruber
<clemens.gruber@xxxxxxxxxxxx> wrote:
> I'd also prefer fixing the underlying problem.

Yes, that would be much better.

> If you take a look at the DMA parts in drivers/tty/serial/imx.c, can you
> spot anything SMP-unsafe?

Not really.

> By the way, can you get your hands on an i.MX6Q board with RS-485 to
> reproduce it?

Unfortunately I don't have such hardware. Even the mx6solo board that
I used to have access in the past I do not have it anymore.

> We could try for a few more weeks to find the bug and if we don't find
> it, adding this rs485-enabled-at-boot-time property sounds good!

Sounds like a good plan, thanks.