[U-Boot] [U-Boot-DM] FDT driver initialization function declaration

Marek Vasut
2012-07-10T15:06:12Z

Dear Simon Glass,

> Hi,
>
> On Tue, Jul 10, 2012 at 3:05 PM, Marek Vasut <marek.vasut@gmail.com> wrote:
> > Dear Michal Simek,
> >
> > > Hi Simon, Wolfgang and others,
> > >
> > > just want to open new topic about FDT driver initialization function
> > > declaration.
> >
> > Ok, my few nits (with consideration of the DM stuff) ...
> > 1) Parsing the DTB is slowish
>
> Yes, particularly early when (for example) the dcache is off and we can't
> store anything.

Well if you use DCache as DRAM ... but that's different tale ;-)

> One solution may be to have a simple way of picking out things that are
> needed early, and placing them in a simple C structure. Things like the
> serial base address (for console_init_f()) might fit this model.

This smells by global data. And picking them from the DTB is still complicated.

> Of course
> this needs a tool to do it. But the advantage is that everything is
> controlled from the fdt but without the performance penalty.
>
> > 2) The DT can bind nicely with the DM, but if you could investigate
> > further and
> > help evaluating possible corner cases, that'd help a lot
>
> I also only just became aware of your tree.

Hum, I did send out the email to many people, announcing this.

> It looks very promising and
> looks like it will solve a number of multi-device / initcall issues we have
> at present.

That's the point (right after making my life easier ;-) ). To squash the growing
number of ad-hoc hacks trying to support multiple devices too.

> > 3) If you could go over the documentation and comment on it, that'd be
> > very nice.
>
> 4) First patches for the DT shall land in next few weeks
>
>
> Do you mean land in mainline, or just in your tree?

I mean in the mailing list :)

> > Wolfgang, is it possible to somehow tag the DM patches so we can later
> > collect
> > these tagged patches to prove we did the amount of work to the university
> > committee? Or maybe simple "dm:" in the subject will suffice.
> >
> > Best regards,
> > Marek Vasut
>
> Regards,
> Simon

Best regards,
Marek Vasut