Re: [PATCH V1] serial: imx: revert setup DCEDTE early and ensure DCD and RI irqs to be off

[Fabio Estevam]

Hi Steve,

On Wed, May 24, 2017 at 7:32 AM, Steve Twiss
<stwiss.opensource@xxxxxxxxxxx> wrote:

> The USB to UART connection gets corrupted.
> If this patch is applied to the kernel, the i.MX6 Q (quad), and only this board as far as
> we know, starts to fail. This does *not* change the i.MX6DL and other sabre boards
> have been tested on kernelci.org and do not see a problem.
>
> An NXP/Freescale SABRESD i.MX6 Q board is requred.
>
> My system for testing is to TFTP the Linux kernel over an ethernet connection. The
> U-boot executes okay and the UART is working at that point. When the kernel loads
> the console trace becomes garbled, in the sense that I get the some characters being
> output to the console, in the style of the kernel starting up, but they are not correct.
>
> I expect the kernel has started ok, but I am unable to read/write through the UART
> console because of corruptions.
>
> Console log with the output I am seeing with linux-next/v4.12-rc2
> --- 8< ---
> U-Boot 2009.08-00001-gf65536a (Jan 12 2015 - 15:47:19)

Thanks for your detailed explanation.

I also have a mx6q sabresd board here, but the error did not happen
when I use a recent U-Boot version.

I would like to use the same U-Boot version here as well to help
debugging this problem.

Could you please let me know which 2009.08 branch you used? Is it any
one from git.freescale.com
http://git.freescale.com/git/cgit.cgi/imx/uboot-imx.git/refs/heads ?

Thanks,

Fabio Estevam