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 27294C001DE for ; Sun, 16 Jul 2023 16:24:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229652AbjGPQYw (ORCPT ); Sun, 16 Jul 2023 12:24:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229461AbjGPQYu (ORCPT ); Sun, 16 Jul 2023 12:24:50 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14543E67; Sun, 16 Jul 2023 09:24:49 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A2D5760D42; Sun, 16 Jul 2023 16:24:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3103C433C7; Sun, 16 Jul 2023 16:24:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689524688; bh=c3PDNjaAmn7fUDUN3J87bGusnUVeCJEj80Th7o+O8UA=; h=Date:From:To:Subject:From; b=HpcK3FvZBXaSxDw5VeiUeOeoPU2g5aAPyJRIvmAAQe82E1Qa9N+ymQxGTkad0pG6b LwB+80EYeQfXuzCGb/r3wqJezfU7+9MCGGY2YiVXWnUsU19u6J/dWHlLC228qg71O9 x2z5QUEWL910PtdVEECNRhvjyWgjLKGiUk+ofeBKIOBOzitr6A814RTACdMfrlT2R9 wpVG4nwTG0u/cmExiGkeC3lqPQZElFpQxlpd5SxtF4B8b2yOXlFMji20rV87OS5xqr jZGdZBcLVYCnhpLVaSUtaB3l5ek7mHQowY4Zo+79Kjjplyd1D04ZnWlcxMCj9yhsbr wBC6aAgATmlPg== Received: by pali.im (Postfix) id 86AEE70C; Sun, 16 Jul 2023 18:24:44 +0200 (CEST) Date: Sun, 16 Jul 2023 18:24:44 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Aurelien Jarno , Florian Fainelli , stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Backporting commits for generating rpi dtb symbols to stable Message-ID: <20230716162444.zzvkm4rh7s7lu37x@pali> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: NeoMutt/20180716 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, I see that raspberry pi bootloader throws ton of warnings when supplied DTB file does not contain /__symbols__/ node. On RPI 1B rev1 it looks like this: dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found dterror: no symbols found Bootloader also propagates these warnings to kernel via dtb property chosen/user-warnings and they can be read by simple command: $ cat /sys/firmware/devicetree/base/chosen/user-warnings ... Upstream Linux kernel build process by default does not generate /__symbols__/ node for DTB files, but DTB files provided by raspberrypi foundation have them for a longer time. I wanted to look at this issue, but I figured out that it is already solved by just recent Aurelien's patches: e925743edc0d ("arm: dts: bcm: Enable device-tree overlay support for RPi devices") 3cdba279c5e9 ("arm64: dts: broadcom: Enable device-tree overlay support for RPi devices") My testing showed that /__symbols__/ node is required by rpi bootloader for overlay support even when overlayed DTB file does not use any DTB symbol (and reference everything via full node path). So seems that /__symbols__/ node is crucial for rpi bootloader even when symbols from them are not used at all. So I would like to ask, would you consider backporting these two raspberry pi specific patches to stable kernel trees? Upstream kernel would get rid of those bootloader warnings and also allow users to use overlayed dtbs... (Btw, do you know if raspberry pi foundation or broadcom provides source code of that bootloader? It would be interesting to understand it or maybe also fix it...)