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 73424C77B7F for ; Mon, 8 May 2023 08:41:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229621AbjEHIlR (ORCPT ); Mon, 8 May 2023 04:41:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59086 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232080AbjEHIlQ (ORCPT ); Mon, 8 May 2023 04:41:16 -0400 Received: from muru.com (muru.com [72.249.23.125]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 834B315EFC; Mon, 8 May 2023 01:41:15 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id E53308111; Mon, 8 May 2023 08:41:14 +0000 (UTC) Date: Mon, 8 May 2023 11:41:13 +0300 From: Tony Lindgren To: Wadim Egorov Cc: Nishanth Menon , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-hardening@vger.kernel.org, upstream@lists.phytec.de, vigneshr@ti.com, kristo@kernel.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, keescook@chromium.org, tony.luck@intel.com, gpiccoli@igalia.com Subject: Re: [PATCH 2/2] arm64: dts: ti: Add basic support for phyBOARD-Lyra-AM625 Message-ID: <20230508084113.GV14287@atomide.com> References: <20230504140143.1425951-1-w.egorov@phytec.de> <20230504140143.1425951-2-w.egorov@phytec.de> <20230504142643.pkzsftrsrqph4vql@banked> <20230505093930.GS14287@atomide.com> <8db31b08-5a8b-f317-a954-c228a08004a8@phytec.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8db31b08-5a8b-f317-a954-c228a08004a8@phytec.de> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org * Wadim Egorov [230505 13:38]: > > Am 05.05.23 um 11:39 schrieb Tony Lindgren: > > * Nishanth Menon [230504 14:33]: > > > Just wondering: if the carrier board can easily work with different > > > SoMs.. in which case, we could do overlay to create the som + carrier > > > overlay to create rdk dtb - this might allow the scheme to scale to > > > additional SoMs and carrier combinations.. and the SoM dtb could be > > > sufficient for something like a bootloader. > > It might be best to limit the overlay usage to devices that might see > > dual use on the carrier board.. Not sure if setting up the entire > > carrier board makes sense as an overlay :) Not sure if folks want to > > debug boot issues on a remote server for example if an overlay is > > needed to boot with Ethernet :) > > Our idea is to create overlays for SoM variants, e.g. an overlay for a SoM > without SPI NOR flash populated. > If we want to reuse a carrier board, we could factor out the carrier board > dts into a dtsi file and provide the needed combinations in form of > different dts files. It probably makes sens to limit the overlays for optional features that are not hardwired. > In the bootloader world the situation is a bit different. > Here we would like to have a universal phycore_am62x "board" that should be > able to handle most carrier board designs using that SoM. And since u-boot > is moving towards having a single source of device trees, this concept will > probably no longer work anymore. So your idea with a SoM dtb sounds > interesting. > I wonder what ideas other SoM vendors have or how it is handled on other > architectures. I'm not sure what the best way to organize things is if there are many SoM and carrier board variants, I guess it depends on the number of the possible permutations :) Regards, Tony