From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754624AbbCQP3W (ORCPT ); Tue, 17 Mar 2015 11:29:22 -0400 Received: from mail.kernel.org ([198.145.29.136]:32977 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754179AbbCQP3R (ORCPT ); Tue, 17 Mar 2015 11:29:17 -0400 Message-ID: <55084848.1000207@kernel.org> Date: Wed, 18 Mar 2015 00:29:12 +0900 From: Kukjin Kim User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.24) Gecko/20111108 Fedora/3.1.16-1.fc14 Lightning/1.0b3pre Thunderbird/3.1.16 MIME-Version: 1.0 To: Javier Martinez Canillas CC: =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= , Javier Martinez Canillas , Kukjin Kim , Olof Johansson , Doug Anderson , "linux-arm-kernel@lists.infradead.org" , "linux-samsung-soc@vger.kernel.org" , Linux Kernel Subject: Re: [PATCH 3/3] ARM: dts: Define stdout-path property for Spring board References: <1426501710-24177-1-git-send-email-javier.martinez@collabora.co.uk> <1426501710-24177-4-git-send-email-javier.martinez@collabora.co.uk> <5506B908.1060007@suse.de> In-Reply-To: X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/16/15 20:28, Javier Martinez Canillas wrote: > Hello Andreas, > Hi, >>> index f02775487cd4..b9ec763a5602 100644 >>> --- a/arch/arm/boot/dts/exynos5250-spring.dts >>> +++ b/arch/arm/boot/dts/exynos5250-spring.dts >>> @@ -25,6 +25,7 @@ >>> >>> chosen { >>> bootargs = "console=tty1"; >>> + stdout-path = "serial3:115200n8"; >> >> Is this a guess or did you verify that against some schematics? >> > > I don't have access to the Spring schematics but it is based on what > is defined in the vendor u-boot for Spring [0]. > > There isn't a Spring specific configuration file but only a > chromeos_daisy.h which is shared by Snow, Spring and Kate (not yet in > mainline): > > #define CONFIG_DIRECT_BOOTARGS \ > "console=ttySAC3," STRINGIFY(CONFIG_BAUDRATE) " debug earlyprintk" > > So I assumed that all daisy-based Chromebooks use the same UART for debug. > >>> }; >>> >>> gpio-keys { >> >> Assuming that bootargs still work, >> > > Yes, the semantics are not changed. The std-out property is only used > as a default if no console= parameter is passed so if you already are > passing one in your bootloader or using the one defined in the /chosen > bootargs by enabling CONFIG_ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND, that > will be used instead of std-out. > >> Reviewed-by: Andreas Färber >> >> I do wonder why this mechanism could not point to the same location as >> bootargs? ("dp-controller"?) The device does not even have screws for > > I did wonder the same indeed but I don't know if you can use a display > as std-out or only works for serial consoles. > >> opening it, so accessing the serial port is highly theoretical. >> > > I see, in that case I think we could just drop this patch if is not > possible to have a serial console even with some soldering like is the > case in Snow, Peach Pit and Peach Pi. > I've applied this whole series so if you guys find any problem on this, please let me know ;) Thanks, Kukjin