From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Alan Cox <alan@linux.intel.com>,
Vitaly Bordug <vitb@kernel.crashing.org>,
Marcelo Tosatti <marcelo@kvack.org>,
linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH] Powerpc 8xx CPM_UART delay in receive
Date: Tue, 14 Aug 2012 15:52:27 +0100 [thread overview]
Message-ID: <20120814155227.018988da@pyramind.ukuu.org.uk> (raw)
In-Reply-To: <201208141426.q7EEQSPc003956@localhost.localdomain>
On Tue, 14 Aug 2012 16:26:28 +0200
Christophe Leroy <christophe.leroy@c-s.fr> wrote:
> Hello,
>
> I'm not sure who to address this Patch to either
>
> It fixes a delay issue with CPM UART driver on Powerpc MPC8xx.
> The problem is that with the actual code, the driver waits 32 IDLE patterns before returning the received data to the upper level. It means for instance about 1 second at 300 bauds.
> This fix limits to one byte the waiting period.
Take a look how the 8250 does it - I think you want to set the value
based upon the data rate. Your patch will break it for everyone doing
high seed I/O.
Alan
next prev parent reply other threads:[~2012-08-14 14:48 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-14 14:26 [PATCH] Powerpc 8xx CPM_UART delay in receive Christophe Leroy
2012-08-14 14:52 ` Alan Cox [this message]
2012-08-16 13:16 ` leroy christophe
2012-08-16 14:29 ` Alan Cox
2012-08-16 14:35 ` leroy christophe
2012-08-16 15:21 ` Alan Cox
2012-09-10 7:09 ` leroy christophe
2012-09-10 13:10 ` Alan Cox
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=20120814155227.018988da@pyramind.ukuu.org.uk \
--to=alan@lxorguk.ukuu.org.uk \
--cc=alan@linux.intel.com \
--cc=christophe.leroy@c-s.fr \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-serial@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=marcelo@kvack.org \
--cc=vitb@kernel.crashing.org \
/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