From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marco Stornelli <marco.stornelli@gmail.com>
Subject: Re: Expose system Serial Number to userspace.
Date: Wed, 29 Aug 2012 18:05:47 +0200
Message-ID: <503E3DDB.8050708@gmail.com>
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To: Brad Arnold <brad@check-it.ca>
Cc: linux-embedded@vger.kernel.org

Il 29/08/2012 17:18, Brad Arnold ha scritto:
> Hi,
>
> I'm working on an embedded board which uses u-boot + linux. At
> manufacturing time, the device serial number will be programmed into OTP
> memory on NAND (probably from within u-boot). We'd like the linux kernel
> to make this serial number available to be read from userspace. Is there
> an accepted method to do this sort of thing?
>
> One idea I had was to make the serial number available as a device node
> (ie: you can simply read the serial number from "/dev/serialnumber"). Then
> there's the question of how the kernel learns the serial in the first
> place (a kernel boot command like parameter passed from u-boot?).
>
> Does this sound sane, or is there a better way to do something like this?
>
> Thanks,
>
> Brad

U-Boot manage a serial number via env variable "serial#". It provides 
several tools. You'll find under tools/env applications to read/write 
env variable of uboot, so reading from Linux is very simple. You should 
use a dedicated little space of flash to store the env variables.

Regards,

Marco