linux-serial.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: jiwang <jiada_wang@mentor.com>,
	Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: gregkh@linuxfoundation.org, jslaby@suse.cz,
	linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
	anton_bondarenko@mentor.com, dirk.behme@de.bosch.com
Subject: Re: [PATCH v1 11/15] serial: imx: initialized DMA w/o HW flow enabled
Date: Fri, 17 Apr 2015 12:31:42 +0200	[thread overview]
Message-ID: <5530E10E.8060808@linutronix.de> (raw)
In-Reply-To: <5530CFEF.9080807@mentor.com>

On 04/17/2015 11:18 AM, jiwang wrote:
> Hello Sebastian

Hallo Jiada,

>> Please make sure it is tagged stable. There is no hint that this is
>> required
>> and as of it now, it breaks v4.0.
> Due to missing of SDMA firmware, uart sdma mode is broken,
> but it is uncovered by this commit on your environment.
> 
>> One question, where do you have the firmware from? I picked the one
>> from FSL's
>> v3.10 SDK and I ended up with FIFO-overflows so it was clearly the
>> wrong one
>> (and the built-in SDMA firmware does not work as expected as you
>> mentioned).
> I got sdma firmware from FSL kernel tree.

Can you post a link please?

>> Is this firmware only required the imx6 series or also for older
>> versions like
>> imx5?
> the firmware only supports imx6 series, AFAIK,

What I meant is if imx5 (and earlier) have a working DMA without the
SDMA firmware which seems to be required for IMX6.

> I checked with Freescale imx6 support team, due to
> licensing issue, I am not entitled to upstream FSL SDMA firmware.
> so seems currently disable SDMA support for uart is our only option
> at the moment.
Disable it please, add a hint in the source so one knows _why_ it has
been disabled and push it stable. In future you would need some kind of
a hint from the sdma driver to let the uart know that the proper
firmware is in place.

Is it okay to send a patch against the linux-firmware tree?
	https://git.kernel.org/cgit/linux/kernel/git/firmware/linux-firmware.git/

> 
> Thanks,
> Jiada

Sebastian

  reply	other threads:[~2015-04-17 10:31 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-09  9:11 [PATCH v1 00/15] serial: imx: misc fix and features Jiada Wang
2014-12-09  9:11 ` [PATCH v1 01/15] serial: imx: add CREAD flag support Jiada Wang
2014-12-09  9:11 ` [PATCH v1 02/15] serial: imx: use locking to stop concurrent access of UCR1 Jiada Wang
2014-12-09  9:11 ` [PATCH v1 03/15] serial: imx: remove unneeded imx_transmit_buffer() from imx_start_tx() Jiada Wang
2014-12-09  9:11 ` [PATCH v1 04/15] serial: imx: TX DMA: clean up sg initialization Jiada Wang
2014-12-09  9:11 ` [PATCH v1 05/15] serial: imx: unmap sg in case of dmaengine_prep_slave_sg() failure Jiada Wang
2014-12-09  9:11 ` [PATCH v1 06/15] serial: imx: unmap scatter gather list in imx_flush_buffer Jiada Wang
2014-12-09  9:11 ` [PATCH v1 07/15] serial: imx: use dma_is_txing to synchronize dma_tx_callback and imx_dma_tx Jiada Wang
2014-12-09  9:11 ` [PATCH v1 08/15] Revert "serial: imx: always wake up the processes in the TX callback" Jiada Wang
2014-12-09  9:11 ` [PATCH v1 09/15] serial: imx: call imx_dma_tx() again in dma_tx_callback Jiada Wang
2014-12-09  9:11 ` [PATCH v1 10/15] serial: imx: disable TDMAEN in imx_flush_buffer() Jiada Wang
2014-12-09  9:11 ` [PATCH v1 11/15] serial: imx: initialized DMA w/o HW flow enabled Jiada Wang
2015-04-09 12:00   ` Sebastian Andrzej Siewior
2015-04-13  7:40     ` jiwang
2015-04-13  8:06       ` Sebastian Andrzej Siewior
2015-04-17  9:18         ` jiwang
2015-04-17 10:31           ` Sebastian Andrzej Siewior [this message]
2015-05-06 16:08           ` Nicolae Rosia
2015-05-06 16:12             ` Sebastian Andrzej Siewior
2015-05-06 16:46               ` Nicolae Rosia
2015-05-06 17:30                 ` Sebastian Andrzej Siewior
2015-05-07 13:55                   ` Nicolae Rosia
2015-05-07 13:58                     ` Sebastian Andrzej Siewior
2014-12-09  9:11 ` [PATCH v1 12/15] serial: imx: start rx_dma once RXFIFO is not empty Jiada Wang
2014-12-09  9:11 ` [PATCH v1 13/15] serial: imx: Enable UCR4_OREN in startup interface Jiada Wang
2014-12-09  9:11 ` [PATCH v1 14/15] serial: imx: Fix issue in software flow control Jiada Wang
2014-12-09  9:11 ` [PATCH v1 15/15] serial: imx: Support sw flow control in DMA mode Jiada Wang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=5530E10E.8060808@linutronix.de \
    --to=bigeasy@linutronix.de \
    --cc=anton_bondarenko@mentor.com \
    --cc=dirk.behme@de.bosch.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jiada_wang@mentor.com \
    --cc=jslaby@suse.cz \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-serial@vger.kernel.org \
    --cc=sebastian@breakpoint.cc \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).