Bug#731345: flash-kernel: add support for DT based kernels on Sheeva Plug

[Ian Campbell <ijc@hellion.org.uk>]

On Thu, 2013-12-05 at 12:46 +0100, Marc Kleine-Budde wrote:
> On 12/05/2013 12:34 PM, Martin Michlmayr wrote:
> > * Marc Kleine-Budde <mkl@blackshift.org> [2013-12-05 11:49]:
> >> That's no option, as non DT Sheeva Plug support has been removed from
> >> the kernel in ffbc50663b69462adc9d97b93b6b92c4fe74b94c:
> >>
> >> ffbc506 ARM: kirkwood: remove support for legacy booting of Sheevaplug
> > 
> > Interesting.  I thought they promised not to remove non-DT support for
> > existing devices.
> 
> I personally don't mind, if it's removed once the DT works properly.
> 
> > Anyway, Marc, so thanks for your patch.  I wonder if it makes sense to
> > add a check to flash-kernel whether DT is required or not.  i.e. that
> > flash-kernel would append the DT blob on 3.12+ kernels on SheevaPlug
> > but not on previous kernels.
> 
> Yes, sounds like the way to go. Otherwise you have to tie certain
> flash-kernel versions to the non-DT and DT kernels. This will probably
> not scale when more no-DT board are removed from the kernel.
> 
> Where should this information go? What about adding another field to
> all.db which limits an entry to certain kernel versions? Something like
> this:

I think it would be sufficient to have a field marking the DTB as
optional and have f-k only do the append if there is a dtb present in
the DTS directory (/usr/lib/linux-X.Y/whatever) for the version it is
handling. If the kernel needs a DTB but doesn't ship one, well ,that's a
bug in the kernel (until we get to the point of burning DTBs into
firmware, but lets not worry about that now!).

I take it from your original patches that the machine ID differs with DT
vs non as well?

> 
> Machine: Marvell SheevaPlug Reference Board
> Kernel-Flavors: kirkwood
> Kernel-Version: < 3.12
> U-Boot-Kernel-Address: 0x00008000
> U-Boot-Initrd-Address: 0x0
> Boot-Kernel-Path: /boot/uImage
> Boot-Initrd-Path: /boot/uInitrd
> Required-Packages: u-boot-tools
> Bootloader-Sets-Root: no
> 
> Machine: Marvell SheevaPlug Reference Board
> Kernel-Flavors: kirkwood
> Kernel-Version: >= 3.12
> DTB-Id: kirkwood-sheevaplug.dtb
> DTB-Append: yes
> U-Boot-Kernel-Address: 0x00008000
> U-Boot-Initrd-Address: 0x0
> Boot-Kernel-Path: /boot/uImage
> Boot-Initrd-Path: /boot/uInitrd
> Boot-DTB-Path: dtb
> Required-Packages: u-boot-tools
> Bootloader-Sets-Root: no
> 
> Marc
> 
>