Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support

From: Tony Lindgren
Date: Tue Jan 17 2017 - 18:33:04 EST


* Vignesh R <vigneshr@xxxxxx> [170117 02:06]:
>
>
> On Tuesday 17 January 2017 11:36 AM, Vignesh R wrote:
> >
> >
> > On Friday 13 January 2017 11:50 PM, Tony Lindgren wrote:
> >> * Vignesh R <vigneshr@xxxxxx> [170113 00:03]:
> >>> This patch series re enables DMA support for UART 8250_omap driver.
> >>>
> >>> Tested on AM335x, AM437x that use EDMA and OMAP5 and DRA74 EVM with
> >>> SDMA.
> >>
> >> Is 8250_omap serial console working for you on omap5 in general?
> >>
> >> I've noticed that it's really unresponsive for me as if the FIFO
> >> interrupt was not working. For example logging in might take several
> >> attempts and a long time with each character showing up much later
> >> after some timeout.
> >>
> >
> > Yes, I did face the same issue on omap5 using 8250_omap driver for
> > console. Looks like this bug has existed all along.
> >
>
> This looks a separate issue, I don't see any errata specific errata wrt
> UART on OMAP5. I will try to debug further.

OK maybe it's something configured or not configured by the bootloader
that we're missing in the Linux driver?

Other than the omap5 issue, 8250_OMAP seems to behave on all variants
that I've tried it with so far.

Regards,

Tony