From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757178AbaITSAV (ORCPT ); Sat, 20 Sep 2014 14:00:21 -0400 Received: from mail-oi0-f49.google.com ([209.85.218.49]:56489 "EHLO mail-oi0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756143AbaITSAT (ORCPT ); Sat, 20 Sep 2014 14:00:19 -0400 Message-ID: <541DC0AF.2060704@gmail.com> Date: Sat, 20 Sep 2014 13:00:15 -0500 From: Rob Herring User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.1.1 MIME-Version: 1.0 To: Tomasz Figa , Alim Akhtar , gregkh@linuxfoundation.org CC: linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Rob Herring , thomas.ab@samsung.com, Marek Szyprowski Subject: Re: [PATCH] tty/serial: samsung: Add earlycon support References: <1410867163-27962-1-git-send-email-alim.akhtar@samsung.com> <541D83AE.1050006@gmail.com> In-Reply-To: <541D83AE.1050006@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/20/2014 08:39 AM, Tomasz Figa wrote: > Hi Alim, > > Please see my comments inline. > > On 16.09.2014 13:32, Alim Akhtar wrote: >> Add earlycon support for the samsung serial port. This allows enabling >> the samsung serial port for console when early_params are parse and processed. >> >> Signed-off-by: Alim Akhtar >> --- >> Documentation/kernel-parameters.txt | 6 ++++++ >> drivers/tty/serial/Kconfig | 1 + >> drivers/tty/serial/samsung.c | 17 +++++++++++++++++ >> 3 files changed, 24 insertions(+) >> >> diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt >> index 5ae8608..e01c0e5 100644 >> --- a/Documentation/kernel-parameters.txt >> +++ b/Documentation/kernel-parameters.txt >> @@ -936,6 +936,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. >> must already be setup and configured. Options are not >> yet supported. >> >> + samsung, There will only ever be 1 samsung uart? This is an ABI to some extent, so you will be stuck with it. >> + Start an early, polled-mode console on a samsung serial >> + port at the specified address. The samsung serial port >> + must already be setup and configured. Options are not >> + yet supported. >> + > > Couldn't you simply parse this from DT? I believe there is already code > parsing stdout property in chosen node for earlycon purposes present in > the kernel. You should support both and it is just a OF_EARLYCON_DECLARE line to add. > Anyway, we already had a patch for this in our internal tree, but it > wasn't submitted because there was no support for early ioremap on ARM > at that time. I haven't been following it since then (and I'm no longer > at Samsung; Marek might be able to take this topic), is it already > available? No, but should be soonish. fixmap parts are being worked on by Kees. Rob