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 8A78EC433F5 for ; Thu, 7 Apr 2022 18:17:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232970AbiDGSTG (ORCPT ); Thu, 7 Apr 2022 14:19:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38492 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233337AbiDGSTF (ORCPT ); Thu, 7 Apr 2022 14:19:05 -0400 Received: from mail-ot1-f53.google.com (mail-ot1-f53.google.com [209.85.210.53]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 029BE398; Thu, 7 Apr 2022 11:17:05 -0700 (PDT) Received: by mail-ot1-f53.google.com with SMTP id b17-20020a0568301df100b005ce0456a9efso4456607otj.9; Thu, 07 Apr 2022 11:17:04 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=3SMplr3NIxarZcsC3NyJ/Iwr/dnvkZ+4jSSz/1c1XSw=; b=gfuAA+MZXBTn/Hb98acz+OCm3dxZuX5U544tDo8i2z1xS5Z7yASJ+Fc9U19VlzY2V+ HDXvmAsleiv55RE+Lip7p9qzgbUBMBNTw34eDzyT4gREWX6hcng6bwuDcLSTJn7IugfN /65F9XBVOyEHwiXRSg3QQkovOmLFbnYfzNWWp62iH305qCo0T1bOFnx5//OTqKlCgthY JYwMiRe7AkzBUA+HcIZGDfpqDFR60hlFIhYNbxmC3PaTuEtvaYs3oonAiGRRpoC3TVEG k6QlhBNr0/jBPH+3k/czFK/cgopyV4i8pO0Mi+qUgJVGYwOlT7lIMuqU2AkqtbOkj3F3 Qn1w== X-Gm-Message-State: AOAM531w57KIYAbQvaf+3DedXyutkdi0gVo3h8UGeNONt3eVTLbD8kgb 69tKwCrHbc5lyal1YiKPaS60HItxTQ== X-Google-Smtp-Source: ABdhPJyHc92fEYOo1RjpNxcvbckJZUIjQ0BYjgcTRqSjC0wHSSqbmSAtBRvdDD4KQpHA3zuefjbC/w== X-Received: by 2002:a05:6830:1ad9:b0:5cd:df9e:271a with SMTP id r25-20020a0568301ad900b005cddf9e271amr5356472otc.142.1649355424284; Thu, 07 Apr 2022 11:17:04 -0700 (PDT) Received: from robh.at.kernel.org (66-90-144-107.dyn.grandenetworks.net. [66.90.144.107]) by smtp.gmail.com with ESMTPSA id z9-20020a056870514900b000e27a6822ecsm449733oak.55.2022.04.07.11.17.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Apr 2022 11:17:03 -0700 (PDT) Received: (nullmailer pid 1725965 invoked by uid 1000); Thu, 07 Apr 2022 18:17:03 -0000 Date: Thu, 7 Apr 2022 13:17:03 -0500 From: Rob Herring To: Joel Peshkin Cc: =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= , Krzysztof Kozlowski , Srinivas Kandagatla , Tom Rini , Florian Fainelli , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "u-boot@lists.denx.de" , Broadcom Kernel List , linux-kernel@vger.kernel.org, =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= Subject: Re: [PATCH] dt-bindings: nvmem: u-boot, env: add Broadcom's variant binding Message-ID: References: <20220406152515.31316-1-zajec5@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Thu, Apr 07, 2022 at 04:55:14AM -0700, Joel Peshkin wrote: > Hi Rafal, > > The first 32b value is a magic number (endian swapped mnemonic of "uEnv" > short for "u-boot environment"). Finding that magic number of a 4K > boundary followed by a length and then a u-boot environment with a valid > CRC permits a scan of the flash partition to locate the environment without > knowing a-priori where it is. So it doesn't need to be described in DT? But how does one identify whether to scan the flash or not. You wouldn't want to do that one every platform. IOW, it's a sufficient discovery mechanism for a custom build, but not generic OS. Rob