From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerry Van Baren Date: Wed, 04 Apr 2007 12:17:35 -0400 Subject: [U-Boot-Users] Warning for mpc8360emds users: fdt-cmd from u-boot-fdt.git In-Reply-To: <4613C84D.6060503@freescale.com> References: <20070403235037.B677E352676@atlas.denx.de> <46137B17.4050104@gmail.com> <46139872.5020707@smiths-aerospace.com> <4613C84D.6060503@freescale.com> Message-ID: <4613CF9F.4040501@smiths-aerospace.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Timur Tabi wrote: > Jerry Van Baren wrote: > >> As a result, if you pull an update from the master u-boot repository, >> you will get the new fdt command, libfdt support, *and modified bootm* >> command. While this shouldn't be a bad thing, it *is not* backward >> compatible with CONFIG_OF_FLAT_TREE. > > I'm a little confused. CONFIG_OF_FLAT_TREE is needed to boot any > powerpc kernel. Are you saying that the two options are mutually > exclusive? Shouldn't CONFIG_OF_LIBFDT be a subset (instead of an > alternative) to CONFIG_OF_FLAT_TREE? That is, you need to define > CONFIG_OF_FLAT_TREE in order for CONFIG_OF_LIBFDT to be recognized? > > Maybe I should have been paying more attention to your libfdt work, but > I was assuming you were just going to alter the back-end handling of OF > trees, not break existing code. Hi Timur, Using CONFIG_OF_FLAT_TREE results in an unchanged u-boot image, no libfdt, no "fdt" command, backwards compatibility. The incompatibility with CONFIG_OF_LIBFDT is that "bootm" does *not* auto-generate nodes ("chosen", "u-boot-env", and "bd_t") when it runs. With CONFIG_OF_LIBFDT, I expect the boot script or the user to use the sequence: * "fdt addr" command to set the blob address * "fdt chosen" to generate/augment the chosen node * "fdt env" to generate the u-boot-env node (optional) * "fdt bd_t" to generate the bd_t node (optional) I view autogenerating fdt entries inside "bootm" as being evil. Obviously, if there are enough people on the Dark Side to overwhelm me, that can be changed. NOTE: I've probably screwed up the multi-image. Note to self, fix it - need to find the fdt blob in a multi-image and implicitly set the "fdt addr" to it. Best regards, gvb