On Mon, Aug 26, 2013 at 04:49:23PM +0200, Gerlando Falauto wrote:

One last question though... what does then the numbering ("@a,b")
stand for? I assume if the output of a plain (i.e. no params)
'lspci' is

It is device,function, but it is only descriptive and not used by
Linux.
 

I should only have a "pci at dd,f" node, with the bus numbering being
imposed by the hierarchy after an actual probing, right?
So the actual bus number is never listed in the device tree (whereas
the "@device,function" is). Is that right?

The reg must encode the bus number according to the OF format:

               33222222 22221111 11111100 00000000
               10987654 32109876 54321098 76543210
 phys.hi cell: npt000ss bbbbbbbb dddddfff rrrrrrrr
phys.mid cell: hhhhhhhh hhhhhhhh hhhhhhhh hhhhhhhh
 phys.lo cell: llllllll llllllll llllllll llllllll
 
bbbbbbbb is the 8-bit Bus Number
ddddd is the 5-bit Device Number
fff is the 3-bit Function Number

Others are 0.

Jason