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

From	Tony Lindgren <tony@atomide.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support
Date	2017-01-18 00:40 +0100
Message-ID	<t0Lw7-4Y5-29@gated-at.bofh.it> (permalink)
References	<sZ55T-6Ta-1@gated-at.bofh.it> <sZeLT-4cm-23@gated-at.bofh.it> <t0v7Y-3oT-19@gated-at.bofh.it> <t0ySe-5M4-15@gated-at.bofh.it>
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* Vignesh R <vigneshr@ti.com> [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@ti.com> [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

Thread

Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support Vignesh R <vigneshr@ti.com> - 2017-01-17 07:10 +0100
  Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support Vignesh R <vigneshr@ti.com> - 2017-01-17 11:10 +0100
    Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support Tony Lindgren <tony@atomide.com> - 2017-01-18 00:40 +0100
      Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support Vignesh R <vigneshr@ti.com> - 2017-01-18 14:20 +0100
        Re: [PATCH 0/3] tty: serial: 8250_omap: Enable DMA support Tony Lindgren <tony@atomide.com> - 2017-01-18 18:20 +0100

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