Expose system Serial Number to userspace.
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 -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Expose system Serial Number to userspace.
On Wed, 29 Aug 2012, Brad Arnold wrote: 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? A serial number field is available from /proc/cpuinfo already. you just have to initialize it through the system_serial_high and system_serial_low global variables. Nicolas -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Expose system Serial Number to userspace.
That's perfect, thanks! Brad -Original Message- From: Nicolas Pitre [mailto:n...@fluxnic.net] Sent: August-29-12 9:51 AM To: Brad Arnold Cc: linux-embedded@vger.kernel.org Subject: Re: Expose system Serial Number to userspace. On Wed, 29 Aug 2012, Brad Arnold wrote: 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? A serial number field is available from /proc/cpuinfo already. you just have to initialize it through the system_serial_high and system_serial_low global variables. Nicolas -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Expose system Serial Number to userspace.
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.storne...@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 -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Expose system Serial Number to userspace.
Il 29/08/2012 18:57, Brad Arnold ha scritto: 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 (Please no top-posting). Of course, if you have got a separate flash partition for the uboot env, you can map it read-only in linux, it's safer. Marco -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Expose system Serial Number to userspace.
On Wed, Aug 29, 2012 at 9:50 AM, Nicolas Pitre n...@fluxnic.net wrote: On Wed, 29 Aug 2012, Brad Arnold wrote: 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? A serial number field is available from /proc/cpuinfo already. you just have to initialize it through the system_serial_high and system_serial_low global variables. Nicolas Actually, I guess even better than initializing through the two variables is to pass the serial directly from u-boot using the tag. Brad -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
