Re: [PATCH 1/6] bootwrapper: arch/powerpc/boot code reorg

On Wed, Aug 02, 2006 at 04:15:05PM +1000, Paul Mackerras wrote:

I wrote:

quoted

The ops structure seems like a reasonable concept, but I question
whether we need to have platform_ops separate from fw_ops, since the
firmware is essentially part of the implementation of the platform.
Also I don't see why we need to do a double indirection to get to each
ops function.

Thinking about this a bit more, why do we need the indirect function
calls at all?  Do we ever want to be able to choose (e.g.) one of
several possible console implementations at runtime?  Don't we know at
compile time which one we will be using, and thus can't we use the
linker to make the necessary linkages?

The hooking up was done at runtime for relocation reasons.
The got relocation code in crt0.S doesn't handle a function address
statically assigned to a structure member.  I don't think its safe
to assume that 0x4000 is safe on all platforms, either, so relocation is
probably a fact of life.  We could hack crt0.S instead, if you prefer?

Mark