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Date:   Thu, 7 Apr 2022 13:17:03 -0500
From:   Rob Herring <robh@kernel.org>
To:     Joel Peshkin <joel.peshkin@broadcom.com>
Cc:     =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= <zajec5@gmail.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Tom Rini <trini@konsulko.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        "u-boot@lists.denx.de" <u-boot@lists.denx.de>,
        Broadcom Kernel List <bcm-kernel-feedback-list@broadcom.com>,
        linux-kernel@vger.kernel.org,
        =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= <rafal@milecki.pl>
Subject: Re: [PATCH] dt-bindings: nvmem: u-boot, env: add Broadcom's variant
 binding
Message-ID: <Yk8qnxqXK7WZvXrS@robh.at.kernel.org>
References: <20220406152515.31316-1-zajec5@gmail.com>
 <CAN3=V2vOVLc95ZYBUDo8J7ast4UQMnZm4uYmX63LpcJdZWnmNQ@mail.gmail.com>
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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