From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 86FC3C433E1 for ; Sun, 5 Jul 2020 18:09:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6243C20715 for ; Sun, 5 Jul 2020 18:09:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593972592; bh=c2a55McBd7AMkKjyMUYwDFgVECADqGqhXoBBFONf7hY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=uWydjHqdTCAo9eT1s7AmQCXrphonBRZIyiVlesyBWz7aXK+gGwXs8PHrAhXyjMnBR uSXrzhc47WgrgADn3MvcBUALUqaJ3uH4aijEsfwkdeVEc4gO990mfA8UQlpPCgUHec 8f0dpPuPT1ceOSLflMy/bLM4UAPxHbn0iUqMvd/w= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727888AbgGESJv (ORCPT ); Sun, 5 Jul 2020 14:09:51 -0400 Received: from mail-wm1-f66.google.com ([209.85.128.66]:53642 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727781AbgGESJu (ORCPT ); Sun, 5 Jul 2020 14:09:50 -0400 Received: by mail-wm1-f66.google.com with SMTP id j18so36795630wmi.3; Sun, 05 Jul 2020 11:09:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=WFXUuYLx9z7kdQD8cxQDN+qE9M0mmvVhR4YuFlGCggU=; b=NoUtpVLssoof5gl60JAvsz4GNZ29f6UcAsXBMBlrZEvz20f8GcF3M5OuwnXgNQB9/j grCfzFalzoad3IJ6e7B5YCyOsDueGnC6IwO5ED9OMG2VXaddy09098WdJ2Ugr7qBVErS 3zh7k7aGv7XK8Ki3ZZjmukofZh1CsHgB3SfhBRdu0Lul+8uQGu+wQQWtou658MABtXam wM0td0+/si7vt8/hc8LjFumptI/UIcVhnpd5n/Bi2PdsHYFWwaioxZN7CON/aC7m6+HQ je3fq0J+PlTyDXBNN/c1S+6p65xtE2wRWRvCUum33AgoplKtHZDTiSed6FiYDGtsSnpz iipw== X-Gm-Message-State: AOAM532RksK9adTQ4Zq8n8xDTYHSOpRTBUF8tASsf1HQr0aKXQkou8i1 dCZVwnvd4Ej+monX9NRn6NA= X-Google-Smtp-Source: ABdhPJxjI4yFt1EotH4VAiKnZjhxmDAOFtIsBKxuNGU1hyL2uOKUIKD6daN9NG2yCKPfXkNal/526Q== X-Received: by 2002:a1c:cc0c:: with SMTP id h12mr3373057wmb.140.1593972588223; Sun, 05 Jul 2020 11:09:48 -0700 (PDT) Received: from kozik-lap ([194.230.155.195]) by smtp.googlemail.com with ESMTPSA id 138sm15606042wmb.1.2020.07.05.11.09.46 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sun, 05 Jul 2020 11:09:46 -0700 (PDT) Date: Sun, 5 Jul 2020 20:09:44 +0200 From: 'Krzysztof Kozlowski' To: Alim Akhtar Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, robh+dt@kernel.org Subject: Re: [PATCH] arm64: dts: exynos: Add minimal bootargs Message-ID: <20200705180944.GB2765@kozik-lap> References: <20200703182536.9190-1-alim.akhtar@samsung.com> <000801d6516a$b6efcb40$24cf61c0$@samsung.com> <20200704102246.GA5975@kozik-lap> <004c01d6526d$18c365e0$4a4a31a0$@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <004c01d6526d$18c365e0$4a4a31a0$@samsung.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 05, 2020 at 07:09:14AM +0530, Alim Akhtar wrote: > Hi Krzysztof, > > Also, why did you use different serial for console? > > > Once UART driver gets probed then console changes to ttySAC0. In case I am using stdout-path only, > after bootconsole is disabled, kernel logs re-start printing from beginning (which might be expected behaviour?) > > [ 0.012416] printk: console [tty0] enabled > [ 0.016491] printk: bootconsole [exynos4210] disabled > [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd032] > [ 0.000000] Linux version 5.8.0-rc3-next-20200703-00008-g4af626444f4a-dirty (alim@alim) (aarch64-linux-gnu-gcc (Linaro GCC 7.4-2019.02) 7.4.1 20181213 [l0 > [ 0.000000] Machine model: Samsung Exynos7 Espresso board based on Exynos7 > No, this is not desired. The fix for it should not be redefining the console to wrong argument. For example on Odroid MC1 this problem does not exist: [ 0.000000] earlycon: exynos4210 at MMIO 0x12c20000 (options '115200n8') [ 0.000000] printk: bootconsole [exynos4210] enabled [ 3.111883] printk: console [ttySAC2] enabled [ 3.111883] printk: console [ttySAC2] enabled [ 3.120102] printk: bootconsole [exynos4210] disabled [ 3.120102] printk: bootconsole [exynos4210] disabled but your console for some reason is tty0... why? Is your console ttySAC2? Maybe it is the effect of alias: serial0 = &serial_2; > > However the question is, are you sure you want earlycon on every, including > > successful boot? On most of the boards we do not enable by default. If > > developer needs, he can choose it for example via U-Boot "setenv opts > > earlycon". > > > Using U-Boot is not the case always, any bootload can be used to boot the Linux, currently I am Coreboot. > And 'earlycon' is not setup by default. > As Espresson board is development board, IMO it is ok to keep it enable all the time, this helps in quickly knowing what going on incase boot fails early. > Let me know if it is ok to keep " console=ttySAC0,115200n8" or shell I just re-spin with only 'earlycon'? or any other suggestion? It should be just earlycon. Best regards, Krzysztof