Flat OF Device Tree for ppc32 [was: Platform bus/ppc sys model...]

Jon Loeliger jdl at freescale.com
Tue Apr 12 01:58:34 EST 2005

On Thu, 2005-04-07 at 12:49, Tom Rini wrote:

> Please post to the list as an RFC.  Thanks.


Apologies to those who have received this notice twice.
I first sent it to the list where it was summarily
denied for size reasons.

I have now posted a tgz file here instead:


What follows is my original email content.

OK, for those keeping score over on the U-Boot list, _this_
message is really intended to be sent to the public list. :-)

Here (as noted above) are my diffs against a clone of
as last pulled a couple days ago. (*)

Please consider this a Request For Comments for now.  Feel free
to apply it and test it out as well, of course. :-)  I'll sign-off
on it when it has ripened some more and gets a nod or two...

These changes relocate almost all of the ppcboot.h definitions
into new files, arc/ppc/syslib/fw_bdt.[ch] and front them
with a new, shim interface in include/asm-ppc/firmware.h.

There is a Kconfig option that allows you to select between
a "bd_t" interface and a non-existant "OF Flat dev tree"
interface.  Choose wisely (default) for now.  It adds the
new fw_bdt.o file.

Some potential gotchas or points to note:

- As of this patch, no interface to any board should change.
  This just isolates the scattered bd_t references to one place.

- On Kumar's advice arch/ppc/boot/simple was totally ignored.
  For now; this round.  It can be next on the hit parade easily.
  It holds the last reference to ppcboot.h still.

- Earlier cut-n-paste of some devices led to me changing a few
  files over in 68k land to remove some now-obsolete ppcboot.h
  related comments justs for completeness.

- I've compiled uImage using defconfigs for the following boards:

        8560_ads        cpci690         ash             redwood5
        8540_ads        ads_8272        TQM8260         est8260
        rpx8260         bseip           mbx             mpc834x_sys
        ocotea          lite5200        hdpu            lopec
        TQM860L         rpxlite         radstone_ppc7d  walnut

- The file include/asm-ppc/ppcboot.h used to contain a nested
  include of linux/types.h that was tacitly used by many files.
  In ripping ppcboot.h out of many platform .h files, I've had
  to add direct #include <linux/types.h> in several places.
  If your board isn't listed above and it looks really broken,
  consider if it needs a <linux/types.h>?


(*) -- BK is dead.  Long live BK!

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