[PATCH v4 5/6] ARM: vexpress: DT-based support for Cortex-A5 and Cortex-A9 based tiles

Arnd Bergmann arnd at arndb.de
Tue Dec 6 18:13:20 EST 2011

On Tuesday 06 December 2011 23:53:46 Arnd Bergmann wrote:
> On Tuesday 06 December 2011 15:43:48 Pawel Moll wrote:
> > This patch adds Flattened Device Trees based support for ARM Ltd.
> > Versatile Express platforms based on Cortex-A5 and Cortex-A9
> > processors.
> > 
> > Signed-off-by: Pawel Moll <pawel.moll at arm.com>
> Acked-by: Arnd Bergmann <arnd at arndb.de>

Actually, I have to take that back. Looking at both patch 5 and 6,
the dt-ca*.c files are almost identical and all the differences are about stuff
that you can find in the device tree:

* The iotable gets initialized from "mrc p15, 4, %0, c15, c0, 0", which would
be fine if that worked on all machines, but in order to unify the two
files, I would recommend searching the flat device tree for the respective
node and only map it if present.

* You have two ways of finding out the number of cores, but looking in
the device tree would just work either way.

* You set the twd_base unconditionally on a5/a9 but never on a7/a15.
This looks correct, but you could just as well see if a twd node exists
and use its base address.

* You only initialize the l2x0 on a5/a9. If a7/a15 don't have a matching
l2x0 device, then calling the same function unconditionally should be harmless.


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