From: b32955@freescale.com (Huang Shijie)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 1/2] serial: imx: remove the DMA wait queue
Date: Fri, 30 May 2014 17:01:30 +0800 [thread overview]
Message-ID: <20140530090128.GA4380@shlinux1.ap.freescale.net> (raw)
In-Reply-To: <857E9EDCA6C0904DB3357321AA9123EBE14B5A2C@NA-MBX-03.mgc.mentorg.com>
On Fri, May 30, 2014 at 09:27:20AM +0000, Wang, Jiada (ESD) wrote:
> Hi Shijie
>
> After apply this patch into our kernel,
> We are facing data hang issue when sending big size file (2M used in test) to uart port
> Note: Rx port is also keep receiving data.
>
> After read the implementation of uart_stop(),
> I feel like, stop_tx() is used to perform flow control when like a XOFF is received.
> Which means no data should be dropped, as they may need to be sent out,
> When next start_tx() is called.
>
> But by calling dmaengine_termiate_all(), the data already be submitted to DMA engine,
> May be lost, thus cause data hang.
>
> What do you think?
This patch has been reverted by Greg.
I also noticed the data loss issue.
thanks
Huang Shijie
prev parent reply other threads:[~2014-05-30 9:01 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-23 4:32 [PATCH 1/2] serial: imx: remove the DMA wait queue Huang Shijie
2014-05-23 4:32 ` [PATCH 2/2] serial: imx: disable the receiver ready interrupt for imx_stop_rx Huang Shijie
2014-05-23 6:10 ` Dirk Behme
2014-05-23 8:04 ` Huang Shijie
2014-05-30 5:52 ` Dirk Behme
2014-05-30 4:53 ` Huang Shijie
2014-05-23 4:40 ` [PATCH 1/2 rebased] serial: imx: remove the DMA wait queue Huang Shijie
2014-05-30 9:27 ` [PATCH 1/2] " Wang, Jiada (ESD)
2014-05-30 9:01 ` Huang Shijie [this message]
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