From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brad Arnold Subject: RE: Expose system Serial Number to userspace. Date: Wed, 29 Aug 2012 10:57:25 -0600 Message-ID: <75d49b059819c35d03995bd86e72d6fb@mail.gmail.com> References: <09ee18b0d2e3d7f34a9e510b3f8d7702@mail.gmail.com> <503E3DDB.8050708@gmail.com> Mime-Version: 1.0 Return-path: In-Reply-To: <503E3DDB.8050708@gmail.com> Sender: linux-embedded-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Marco Stornelli Cc: linux-embedded@vger.kernel.org That'll help me move along. I'm currently storing the mac and serial in the u-boot environment, but I was thinking I might want to move those two to the OTP. But at least having some level of write protection in u-boot is nice. I wasn't aware that this existed, because it's disabled by default in the config for Marvell boards. I'll have to look at that example program futher... Brad -----Original Message----- From: Marco Stornelli [mailto:marco.stornelli@gmail.com] Sent: August-29-12 10:06 AM To: Brad Arnold Cc: linux-embedded@vger.kernel.org Subject: Re: Expose system Serial Number to userspace. 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