linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: 21285 serial driver deadlock(?) fix
Date: Fri, 1 Jan 2010 20:29:16 +0000	[thread overview]
Message-ID: <20100101202916.GD16220@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1262039226.28196.125.camel@localhost>

On Mon, Dec 28, 2009 at 05:27:06PM -0500, Steve Moskovchenko wrote:
> I've modified the ISR to call a different version of stop_tx, which uses
> disable_irq_nosync() instead. This gave me a working console.

That's right - however, I'm not sure whether the stop_rx also needs
to be a _nosync version.

> Another issue with the driver is the baud rate calculation, which seems
> broken for me. I had to comment out the lines that write to the BRG
> register (not in this patch), but this may be a result of my board using
> a different clock rate than a real EBSA285. Maybe I will look into that
> later.

Works for me.  Could be that your 21285 is clocked at a different rate,
in which case the 21285 timers are also going to be wrong.  You need to
specify the 21285 clock rate to the booting kernel via ATAGs or the
"mem_fclk_21285=" command line option.

There is no way for the kernel to autodetect this; it must be passed to
the kernel in some manner from something like a boot loader.

  reply	other threads:[~2010-01-01 20:29 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-28 22:27 21285 serial driver deadlock(?) fix Steve Moskovchenko
2010-01-01 20:29 ` Russell King - ARM Linux [this message]
2010-01-04  8:11 ` Simon Kagstrom
     [not found]   ` <20dd1d411001051037o74fb1187j608889fae0271547@mail.gmail.com>
2010-01-11  9:57     ` Simon Kagstrom
2010-01-12 17:12       ` Steve M
2010-01-13  8:17         ` Simon Kagstrom

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=20100101202916.GD16220@n2100.arm.linux.org.uk \
    --to=linux@arm.linux.org.uk \
    --cc=linux-arm-kernel@lists.infradead.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;
as well as URLs for NNTP newsgroup(s).