Mark A. Greer wrote:
On Thu, Mar 01, 2007 at 09:01:24AM -0500, Jerry Van Baren wrote:
Hi all,
This is a Request for Advice.
Hi Jerry.
One minor thing. I'd just want to remind you that we shouldn't stray too far from the OF interface. The bootwrapper code sits on top of either the FDT access interface or the true OF DT access interface. The closer we keep the two, the cleaner & easier the we can keep the bootwrapper code.
Mark
Hi Mark,
Understood, but that isn't really my battle. David Gibson created the libfdt interface so any linux/bootwrapper changes are really his battle. I'm working in u-boot land so linux/bootwrapper aren't in my problem domain - using libfdt in u-boot doesn't affect the bootwrapper code. Having said that, I'm hoping for shared code synergy, which would require the linux kernel to adopt libfdt as a replacement for flatdevtree.[ch]. David has also talked about using libfdt in the dtc suite, so there is potentially a three way synergy.
The flattened device tree which is passed from u-boot to linux is unchanged*, so the interface is the same at that level (to state the obvious).
David's libfdt is a potential replacement for flatdevtree.c. I have pursued using libfdt rather than flatdevtree (in u-boot) because the interface is much cleaner (IMHO, and, I'm sure, IDHO). Of course "much cleaner" is the fancy way of saying "not compatible." :-/ On the other hand, I looked at arch/powerpc/boot/of.c, ops.h, and flatdevtree_misc.c. It looks like it would be relatively easy to redo flatdevtree_misc.c to glue to libfdt instead of flatdevtree.c (he says blithely).
* ...other than a backwards compatible version 16 -> 17 upgrade.
Best regards, gvb