From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: Adding aliases to mmc Date: Fri, 20 Sep 2013 11:03:12 -0600 Message-ID: <523C7FD0.3030006@wwwdotorg.org> References: <5239C40C.9030503@wwwdotorg.org> <5239DC65.3080803@gmail.com> <5239DF55.8010308@wwwdotorg.org> <523A8A08.2060508@gmail.com> <523C7231.7040701@wwwdotorg.org> <523C79C4.1070308@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <523C79C4.1070308-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Dirk Behme Cc: Fabio Estevam , linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Sascha Hauer List-Id: linux-mmc@vger.kernel.org On 09/20/2013 10:37 AM, Dirk Behme wrote: > Am 20.09.2013 18:05, schrieb Stephen Warren: >> On 09/18/2013 11:22 PM, Dirk Behme wrote: >> ... >>> If you have an embedded system were you just care a little about boot >>> time you don't want to do anything like U-Boot's "part uuid" every time >>> you boot. Or even worse, you just have a minimalistic boot loader (e.g. >>> U-Boot's SPL) which doesn't know anything about UUIDs and file systems. >>> >>> As mentioned above, no I don't think UUIDs work for production embedded >>> systems. >> >> As I said above, whatever generates the filesystem image can easily >> embed the appropriate UUID in the system's boot scripts or bootloader >> environment. There's no need to run the "part" command at run-time if >> there's a more appropriate flow for your situation. > > Using a simple boot loader as an example, there are no boot scripts or > boot loader environment. The only thing the boot loader does is loading > the device tree and the kernel into RAM. Where do you want to embed an > UUID in such a product? I think the initrd would be typical. > To my understanding, the UUID is different for each SD card/eMMC, correct? Yes by default. Although for an embedded product with a fixed eMMC, there's no reason you couldn't make every device have the same UUID for the fixed device. Obviously you wouldn't want to do that for any removable device. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html