[PATCH v2 3/3] PCI: ARM: add support for generic PCI host controller

On Thu, Feb 13, 2014 at 06:26:54PM +0000, Jason Gunthorpe wrote:

On Thu, Feb 13, 2014 at 05:28:20PM +0100, Arnd Bergmann wrote:

quoted

quoted

Huh?  The reg property clearly has the size in it (as shown in the
example below).  I guess I was just asking for the description
here to say what the size was for the 2 compatibles since its
fixed and known.

It's still an open question whether the config space in the reg
property should cover all 256 buses or just the ones in the
bus-range. In the latter case, it would be variable (but
predictable) size.

The 'describe the hardware principle' says the reg should be the
entire available ECAM/CAM region the hardware is able to support.

This may be less than 256 busses, as ECAM allows the implementor to
select how many upper address bits are actually supported.

Ok, but the ECAM/CAM base always corresponds to bus 0, right?

IMHO, the bus-range should be used to indicate the range of busses
discovered by the firmware, but we have historically tweaked it to
indicate the max range of bus numbers available on this bus (I think
to support the hack where two physical PCI domains were roughly glued
into a single Linux domain).

Ok, so this answers Kumar's point about the reg property. I'll augment it
with a size.

Will