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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6ECDC433EF for ; Mon, 6 Jun 2022 14:32:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239744AbiFFOca (ORCPT ); Mon, 6 Jun 2022 10:32:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239568AbiFFOcZ (ORCPT ); Mon, 6 Jun 2022 10:32:25 -0400 Received: from mail-ej1-x62f.google.com (mail-ej1-x62f.google.com [IPv6:2a00:1450:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DA5E19F8A; Mon, 6 Jun 2022 07:32:22 -0700 (PDT) Received: by mail-ej1-x62f.google.com with SMTP id m20so29283807ejj.10; Mon, 06 Jun 2022 07:32:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=LIT3NTOsC7NowXp4Z1Nxh6Sac8z4PgQBaEerVN5FpP8=; b=almcHK6LQ2DyRgGvCWV8q7K7XfxP4/2NblraJHlMYjlTl92TI02I9+HCNGP7EEPM88 GX73xqp8vvf+b3pqB8IDQQTvEWRah+58XPnuFp2Nyooq5sHCUM2uzjgtEkFPzJTfqxN8 7ywRCM37wEIg8lah6XSyVoIr6Q9nOJ3WIhDGqyHeGAIkswf/iktkC40m7rhDPL7cSeI2 P5xry8p1VUqb2riidZUbHGqYAIg2wgnVdHkKFG1NLYXUum/LkZU9b877p9yiO3GNOio7 OhUNPHgKFRuKWBGrEMSj92+1SiMVNDfwvIbwUkPDiY+Vohd5H0C0hm1svSG4urhiMGGj FJKg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=LIT3NTOsC7NowXp4Z1Nxh6Sac8z4PgQBaEerVN5FpP8=; b=yCwf8Pl1rlLHFWYSFbArdnETIM8LQaow1Pg6cBtvwlax1dhYu0G0L14wNDrzvFuqhJ gfWcqdsmERHlN9LvI8On1foNMeQKOgHOSyJcFKqDLO63OD2mbwZ6WcZ+TTY5BrLjwZOq YjgLO02CnF0bDP0eUPvKVqkyJ7rrwgiVbuRRtTB5vQ6Qm0kncJySMhpH4aamSqfEtFmJ mG+3tRlGNdNyJk7uNXNxbbpqlg7saONf7EgfHwSys0KzhuXjq4oDX2DlW1AkUCMkKiGD B8ZyaTSbUVeX1KCKeRJ6AU4DR4n0ZMEgQCqYrP22WCoy7i17AwB4vGvimdzq7746INKJ f55g== X-Gm-Message-State: AOAM533ft4JftjmFiZPGu/sD7dru1I89aoyxMTohCfYeOvft0TGoBOoB bATzfwvavgICaIwINWvHoksIQZuXqsozhuFDkCc= X-Google-Smtp-Source: ABdhPJy6UQPbd2ONT3dQRyiW5E4Yq2lQTA1whZjW8/aroaW09EW7+O9WEkxv0LWx4JEWD5Ja2ZFia5j7aDz12l3YNco= X-Received: by 2002:a17:906:d9d9:b0:710:f2ae:b455 with SMTP id qk25-20020a170906d9d900b00710f2aeb455mr10522126ejb.77.1654525941064; Mon, 06 Jun 2022 07:32:21 -0700 (PDT) MIME-Version: 1.0 References: <1880b7a7-2353-c381-5afb-1d4224eb223b@molgen.mpg.de> <477007d7-e573-56dd-90de-877eeebd5c4c@molgen.mpg.de> In-Reply-To: <477007d7-e573-56dd-90de-877eeebd5c4c@molgen.mpg.de> From: Andy Shevchenko Date: Mon, 6 Jun 2022 16:31:44 +0200 Message-ID: Subject: Re: Non-working serial console To: Paul Menzel Cc: Greg KH , "open list:SERIAL DRIVERS" , LKML Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 6, 2022 at 5:44 AM Paul Menzel wrote: > Am 04.06.22 um 11:04 schrieb Greg KH: ... > I am still confused, that `earlyprintk=3DttyS0,115200,keep` works though > despite `CONFIG_SERIAL_8250=3Dm`. Doesn=E2=80=99t that mean, that Linux > nevertheless contains some code to initialize the serial console, and > send data to it? If you keep x86 in mind, then yes, three different console code handling (decompressing stage, boot stage, driver stage) + earlyprintk (on top of the same code for decompressing / booting stages) + earlycon (this is actually a driver:ish stage). --=20 With Best Regards, Andy Shevchenko