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

Tarl Neustaedter tarl-b2 at tarl.net
Sat May 28 20:19:32 CEST 2011

On 2011-May-28 07:48 , Andreas Färber wrote:
> [...]
> That's what I thought, too... but Segher said otherwise in January, 
> and Tarl said the internal cell size (that I'm trying to change here) 
> were different from the guest-visible 32-bit cell size. Through the 
> use of prog_arg_t the CIF is supposed to remain 32-bit.

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.

On SPARCs, we have three things we refer to as cell size:
- The internal cell size (defined by /n), 64 bits
- The device tree cell size, defined by 1275 to always be 32 bits
- The cell size presented to FCode version 2 drivers (plug-in cards), 
which is emulated to be 32 bits.

More information about the OpenBIOS mailing list