[U-Boot] [PATCH 3/6] sunxi: add Cubieboard2 support

[Siarhei Siamashka <siarhei.siamashka@gmail.com>]

On Thu, 24 Jul 2014 11:18:15 +0800
Chen-Yu Tsai <wens@csie.org> wrote:

> On Thu, Jul 24, 2014 at 11:12 AM, Siarhei Siamashka
> <siarhei.siamashka@gmail.com> wrote:
> > On Thu,  5 Jun 2014 19:00:14 +0100
> > Ian Campbell <ijc@hellion.org.uk> wrote:
> >
> >> This is a sun7i (A20) based followup to the sun4i (A10)
> >> Cubieboard. It has GMAC using MII mode.
> >>
> >> Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
> >> Acked-by: Hans de Goede <hdegoede@redhat.com>
> >
> > This board is using exactly the same PCB as the Cubieboard1. And only
> > the SoC is different (Allwinner A20 instead of the pin-compatible
> > Allwinner A10).
> >
> > Before piling up more board configurations, we might want to consider
> > supporting both Cubieboard1 and Cubieboard2 with a single u-boot binary
> > (and perhaps keep Cubieboard1 and Cubieboard2 as aliases in boards.cfg).
> > The Allwinner SoCs have support for runtime identification of the SoC
> > type (sun4i/sun5i/sun7i) via the VER_REG (Version Register) located at
> > the address 0x01C00024 as explained in the Allwinner A20 user manual.
> > This requires replacing all the CONFIG_SUN4I/CONFIG_SUN5I/CONFIG_SUN7I
> > ifdefs in the u-boot code with a runtime SoC type checks, but there
> > are not too many places affected (mostly just the DRAM code).
> 
> A20 will need PSCI for SMP and virtualization support.
> (I know the related code isn't in there yet.)
> Won't this be slightly hard to do if you mix them together?

Thanks, that's a good point. Do you expect any special challenges other
than just having to handle runtime SoC detection in more places and
deal with larger final binaries on the hardware, which does not need
PSCI itself?

-- 
Best regards,
Siarhei Siamashka