[PATCH] Start arch/powerpc/boot code reorganization

Segher Boessenkool segher at kernel.crashing.org
Sat Sep 23 20:15:19 EST 2006

> All I'm try to say is that "fw,address" is just like the "reg"  
> property
> except that it holds the effective addr not the physical addr and the
> size of the address is determined by the existence of "/cpus/64-bit"
> not #address-cells.  That's all.

Sounds good.

>> Yes.  Except a "cell" is not what you think it is.  A "cell" is the
>> size of numbers OF deals with internally; just deal with it.  Of
>> course, there's things like "#address-cells", which really mean
>> "#-32bit-things-per-address".
> Okay, well, when I talked about cells I meant "#-32bit-things-per- 
> address".
> Obviously it was silly of me to think that "#address-cells" meant  
> the # of
> address cells...

Some background might clear things up (or not)...  A "cell" is the
unit of data in a Forth system.  When OF was young (and not yet
called OF), all systems were 32-bit, and the 32-bit-thingies in
the properties (which weren't yet called properties) in the device
tree were called cells as well.  When 64-bit came into the picture,
everything fell apart.  The "correct" name for the property thingies
now is "integers as encoded with encode-int".  Maybe we can compromise
on calling it "property cells" or something.

The situation is even worse with "package", let's not go there :-)


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