[OpenBIOS] [RFC 2/3] ppc64: Switch to 64-bit cell size

Segher Boessenkool segher at kernel.crashing.org
Sat May 28 20:30:42 CEST 2011

> If I recall correctly what I said, the device-tree property cell size 
> is _always_ 32-bit, regardless of what the internal cell size is.

Don't call that "cell size" :-)  The OF standard calls it "a 32-bit 
as encoded by encode-int".

> - The cell size presented to FCode version 2 drivers (plug-in cards), 
> which is emulated to be 32 bits.

Do you mean the size of (lit) here?  That's 32-bit signed always, yes.  
FCode cell size is the same as the Forth cell size.  Most FCode programs
written for 32-bit systems work as-is on 64-bit systems; some need some
fixes.  Programs that need 64-bit numbers (for example, for devices that
have 64-bit registers) need some careful coding.


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