-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Tue, 6 Aug 2013 11:53:02 +0800 Andy Green <[email protected]> wrote:
> On 6 August 2013 11:05, Rob Herring <[email protected]> wrote: > > -----BEGIN PGP SIGNED MESSAGE----- > > Hash: SHA1 > > > > On 08/05/2013 04:41 PM, Dennis Gilmore wrote: > >> Hi all, > >> > >> As part of the unified features in u-boot thread I said that I > >> would work to get distros to agree to a common location that u-boot > >> will be able to assume exists for it to transparently load dtbs > >> from for us. > >> > >> I would like to propose /boot/dtb/ > >> > >> I think it needs to be in /boot/ to allow for booting from systems > >> with / and /boot on separate partitions. I believe Ubuntu and > >> hence Debian put them in /lib somewhere today. Fedora puts them in > >> /boot/dtb-<kernel version>. im not sure where the other distros > >> put them. > > > > A DTB should not be tied to a kernel version. I realize that is a > > reality for some boards, but lets not encourage that. There are also > > plans to remove dts files from the kernel. > > > >> > >> I think that until they are decoupled from the kernel Fedora would > >> have /boot/dtb be a symlink to the latest installed kernel. once > >> its decoupled it would be the location where the dtbs are > >> installed. > > > > If /boot/dtb is THE dtb to use, does more than that need to be > > specified (at least from a bootloader perspective). /boot/dtb/ is the directory that contains all the dtbs. omap and other platforms, have a findfdt function that will tell you the expeted dtb filename for the board. we just need to put them in a know location. > If I understood you correctly, that'd be needlessly limiting one image > to one board. > > Consider an SD Card + CONFIG_ARCH_MULTIPLATFORM kernel you can pull > out and plug in to use on a variety of different boards, the > bootloader would need to identify the correct dtb and pass it to the > kernel. depending on the system you would need to update the u-boot installed into the card, a scriptable task, or ensure that the installed u-boot has the unified features needed. but I fully expect that it something people can and will want to do. > U-Boot is bound up with compile-time decisions about targeting a > single board at the moment, but if we're talking about long term > decisions like /boot/dtb/ just like ARM isn't the only consideration > U-Boot is not the only bootloader. I hope the long term outcome here is that u-boot or any other bootloader would be able to know where to find the dtb file regardless of distro because we all honour and do the same thing. > Once kernels capable of running a single binary on many platforms are > common (they're already workable) pressure for the bootloader to do > likewise will increase. So it'd be a shame to block that by choosing > a dtb convention that assumes there's only one on the image. They exist today in fedora, as of Fedora 19 we are shipping a multiplatform kernel. The same images can run on multiple boards. I don't want to limit what systems are supported in any way. but come up with a flexible portable setup. Dennis -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iEYEARECAAYFAlIAeKgACgkQkSxm47BaWfflkACgi3f9M8CrZXD7t7HwgH9WlmQf mcgAoK0yvcXtpr0ZQRoLeKkmUYWKb7Y0 =lQyQ -----END PGP SIGNATURE----- _______________________________________________ cross-distro mailing list [email protected] http://lists.linaro.org/mailman/listinfo/cross-distro
