How to move from /ppc/ to /powerpc/

[Kim Phillips]

On Tue, 12 Sep 2006 17:33:16 +0200
Fredrik Roubert <roubert at df.lth.se> wrote:

> Hi!
> 
> I have a custom board on which I currently run Linux 2.6.18-rc6
> configured for MPC834x_SYS in the /ppc/ tree, which just a few minor
> changes. Now I'm interested to move to using the /powerpc/ source tree
> instead, but I can't figure out exactly what steps are necessary to do
> this.
> 
> Does anyone run a MPC834x_SYS built with ARCH=powerpc?
> 
yes

> I boot the board with U-Boot (version 1.1.4, customized), and I assume
> that I need to add some stuff for this new device tree thing, but I
> can't figure out exactly what the kernel will expect.

the kernel expects a pointer to a device tree instead of a bd_t.  The 8349EMDS device tree source is now in linux/arch/powerpc/boot/dts.  You'll need the device tree compiler (dtc) from jdl.com to build your flat device tree binary (dtb; what the kernel expects).

> 
> Does anyone have some pointers on how to do this?
> 
Matt's u-boot patches address the issue well for 85xx, they are straightforward to adapt to 83xx:

http://sourceforge.net/mailarchive/forum.php?thread_id=15518792&forum_id=12898

they allow you to tftp the dtb into mem, and "bootm ${loadaddr} - ${oftaddr}" to start an ARCH=powerpc kernel. 

> Cheers // Fredrik Roubert

Kim