On Wednesday 11 July 2007, Christoph Hellwig wrote:
> On Wed, Jul 11, 2007 at 08:56:58AM -0700, David Brownell wrote:
> > > Umm, this is about the fifth almost identical implementation of
> > > the clk_ functions. Please, please put it into common code.
> > >
> > > And talk to the mips folks which just got a similar comment from me.
> >
> > You mean like a lib/clock.c core, rather than an opsvector?
>
> I mean an ops vector and surrounding wrappers. Every architecture
> is reimplementing their own dispatch table which is rather annoying.
ARM doesn't. :)
But then, nobody expects one kernel to support more than one
vendor's ARM chips; or usually, more than one generation of
that vendor's chips. So any dispatch table is specific to
a given platform, and tuned to its quirks. Not much to share
between OMAP and AT91, for example, except in some cases maybe
an arm926ejs block.
> What would a lib/clock.c do?
Some folk have suggested defining a core "struct clk {...}" with
some of the basics -- refcount, parent, maybe enough to support
the clk_get() lookup or even more -- so that the more obvious
stuff doesn't need constant re-implementation, and so that new
implementations become easier. Platforms would wrap that with
whatever extensions they need.
I've not seen a solid proposal for such a thing, and it's not
clear to me how that would play with with older code (e.g. any
of the ARM implementations).
And I'm sure there are other suggestions ... I was mostly just
wondering just what you were suggesting.
- Dave
