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Date:   Thu, 26 Mar 2015 16:09:20 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     James Hogan <james.hogan@imgtec.com>
Cc:     Ralf Baechle <ralf@linux-mips.org>, linux-mips@linux-mips.org,
        linux-kernel@vger.kernel.org, Jiri Slaby <jslaby@suse.cz>,
        Jason Wessel <jason.wessel@windriver.com>,
        kgdb-bugreport@lists.sourceforge.net
Subject: Re: [PATCH 9/9] ttyFDC: Implement KGDB IO operations.
Message-ID: <20150326150920.GC21726@kroah.com>
References: <1422530054-7976-1-git-send-email-james.hogan@imgtec.com>
 <1422530054-7976-10-git-send-email-james.hogan@imgtec.com>
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On Thu, Jan 29, 2015 at 11:14:14AM +0000, James Hogan wrote:
> Implement KGDB IO operations for MIPS Fast Debug Channel (FDC). This can
> be enabled via Kconfig, which also allows the channel number to be
> chosen.
> 
> The magic sysrq hack is implemented in the TTY driver, detecting just ^C
> for the KGDB channel, and ^O followed by a letter for the FDC console
> channel.
> 
> The KGDB operations are reasonably efficient thanks to the flush
> callback, with a 4 byte buffer being used in both directions to allow up
> to 4 bytes to be encoded per FDC word. Reading of data for KGDB will
> discard any data received on other channels, which clearly isn't ideal,
> but given that there is a single FIFO shared between channels we can't
> do much better.
> 
> Signed-off-by: James Hogan <james.hogan@imgtec.com>
> Cc: Ralf Baechle <ralf@linux-mips.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: Jiri Slaby <jslaby@suse.cz>
> Cc: Jason Wessel <jason.wessel@windriver.com>
> Cc: linux-mips@linux-mips.org
> Cc: kgdb-bugreport@lists.sourceforge.net

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>