[PATCH 6/6 v4] ARM: realview: basic device tree implementation

On Monday 01 September 2014 13:03:13 Russell King - ARM Linux wrote:

On Fri, Jul 25, 2014 at 05:58:24PM +0200, Arnd Bergmann wrote:

quoted

On Friday 25 July 2014 16:50:10 Russell King - ARM Linux wrote:

quoted

I toyed with the idea of adding the standard cache size specifications
to the L2C code, it sounds like there's a reason to do that now.

Let's not mess around with adding stuff like the above to work around
the L2 code not parsing the appropriate specs from DT, let's do the
right thing and add bindings to allow DT to provide the cache geometry.

Yes, please!

That would actually reduce the realview to just the dma_zone_size
definition, and I think someone also posted a patch to get that from
DT recently. Having realview booting with an empty board file would
be ideal.

I did have a patch in my L2C cleanup series to provide these properties,
but it got discarded - even though we have existing platforms which
provide these values.

The reason for that was because requiring new properties causes a DT
breakage - previous versions of the DT suddenly stop working because
the values necessary to setup the L2C have been removed from the
kernel, and the older DT files do not contain the neccessary values
either.

But in case of realview or any other platform that does not have
mainline DT support, nothing would break. There is no need to remove
the settings from the kernel, I would just prefer not to add any
other ones.

	Arnd