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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 947F1C35644 for ; Fri, 21 Feb 2020 09:34:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6C3A320722 for ; Fri, 21 Feb 2020 09:34:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="KmGNlDaQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727794AbgBUJer (ORCPT ); Fri, 21 Feb 2020 04:34:47 -0500 Received: from ssl.serverraum.org ([176.9.125.105]:44453 "EHLO ssl.serverraum.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726984AbgBUJer (ORCPT ); Fri, 21 Feb 2020 04:34:47 -0500 Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id C90A023D18; Fri, 21 Feb 2020 10:34:43 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1582277684; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Snop1RpX2rRCwWvJOlE+k0QPMCh/eFbh+WZC0GsS4uA=; b=KmGNlDaQ0PxdmjCYZnUUKedfMyyTcUd1gXD7yIRoHmxoX8UnGY0zb8lm/piMWP+VR63s+Q xDwYHFxwJHy9ZFrwvVkKljKvR6iTMLBWGm73MzpxQ7dvFMbKyX8tHOeOi7EYExgDLXEGCm m1eae/F2FAQ5vFJE9UpYBMB+T+cGQ+g= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 21 Feb 2020 10:34:43 +0100 From: Michael Walle To: Peng Fan , Greg Kroah-Hartman Cc: linux-serial@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Rob Herring , Mark Rutland , Shawn Guo , Leo Li , Jiri Slaby , Yuan Yao , Vabhav Sharma Subject: Re: [PATCH 1/7] Revert "tty: serial: fsl_lpuart: drop EARLYCON_DECLARE" In-Reply-To: References: <20200220174334.23322-1-michael@walle.cc> Message-ID: <51db0e6ba10b4b32dab207e0df8ef0d8@walle.cc> X-Sender: michael@walle.cc User-Agent: Roundcube Webmail/1.3.10 X-Spamd-Bar: + X-Rspamd-Server: web X-Rspamd-Queue-Id: C90A023D18 X-Spamd-Result: default: False [1.40 / 15.00]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; TAGGED_RCPT(0.00)[dt]; MIME_GOOD(-0.10)[text/plain]; DKIM_SIGNED(0.00)[]; RCPT_COUNT_TWELVE(0.00)[13]; NEURAL_HAM(-0.00)[-0.601]; RCVD_COUNT_ZERO(0.00)[0]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_MATCH_FROM(0.00)[]; SUSPICIOUS_RECIPS(1.50)[] Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Am 2020-02-21 02:30, schrieb Peng Fan: >> Subject: [PATCH 1/7] Revert "tty: serial: fsl_lpuart: drop >> EARLYCON_DECLARE" >> >> This reverts commit a659652f6169240a5818cb244b280c5a362ef5a4. >> >> This broke the earlycon on LS1021A processors because the order of the >> earlycon_setup() functions were changed. Before the commit the normal >> lpuart32_early_console_setup() was called. After the commit the >> lpuart32_imx_early_console_setup() is called instead. > > How do you pass earlycon args to kernel? earlycon=lpuart32,mmio32be,0x2950000,115200 please note that there are two possible declarations: (1) an OF/ACPI based earlycon, eg just "earlycon" on the bootargs and (2) an elaborate one where you can give the offset and access method yourself, eg. the one from above. (1) will still work even with the EARLYCON_DECLARE() removed. But (2) will search through all possible OF_DELARE_EARLYCON(lpuart32,..) EARLYCON_DECLARE(lpuart32,..) and doesn't take the compatible into account. So which setup function is actually called depends on (a) the order of the OF_DECLARE_EARLYCON() and EARLYCON_DECLARE() statements and (b) on the compiler (thats just a guess!). For me, the order in which it will actually end up in the __earlycon_table is reversed, eg. the last one is called. So now that you've removed the EARLYCON_DECLARE() the last one is the imx setup function which will add the reg offset and doesn't work on LS1021A. I've proposed a fix of the underlying problem [1]. But that fix also requires the EARLYCON_DECLARE() in this driver. -michael [1] https://lore.kernel.org/linux-serial/20200220174607.24285-1-michael@walle.cc/