From: John Ogness <john.ogness@linutronix.de>
To: Peter Hurley <peter@hurleysoftware.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Tony Lindgren <tony@atomide.com>, nsekhar@ti.com,
        linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
        linux-omap@vger.kernel.org
Subject: Re: [PATCH] tty: serial: 8250_omap: do not defer termios changes
References: <8737r7ght7.fsf@linutronix.de>
	<570339E8.6010808@hurleysoftware.com>
Date: Mon, 11 Apr 2016 10:18:22 +0200
Message-ID: <87y48kftip.fsf@linutronix.de>
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On 2016-04-05, Peter Hurley <peter@hurleysoftware.com> wrote:
> On 03/31/2016 01:41 AM, John Ogness wrote:
>> It has been observed that the TX-DMA can stall
>
> Does this happen on any other OMAP part besides am335x?
> I looked back over the LKML history of this and didn't see
> any other design implicated in this problem.

I just ran the tests again using 4.6-rc2. I am able to reproduce the
dma-tx stall with am335x/edma and dra7/sdma.

Note: To achieve the stall, both the delayed_restore and the
      rx_dma_broken features of the mainline 8250_omap driver needed to
      be removed.

John Ogness