[OpenBIOS] [PATCH 3/6] Introduce va2pa() and pa2va() functions for PPC for subsequent use by OFMEM.

Mark Cave-Ayland mark.cave-ayland at siriusit.co.uk
Sat Jan 1 14:09:15 CET 2011

On 30/12/10 23:46, Andreas Färber wrote:

> Only for sparc! For ppc I located it further below, beneath the
> (aligned) hash map iirc.

Ah okay.

> Obviously we all try to set up sane translations initially, so I was
> more worried about runtime. But on second thoughts, if someone remaps
> our malloc zone with whatever alignment then we're doomed anyway.
> I must admit that I still don't understand which case exactly broke the
> alignment on sparc in the first place, so I'm unable to provide
> pinpointed solutions. I'm regarding these as general functions - thus a
> va2pa() that doesn't respect the va translations is broken IMO.

The issue is that the old routines just aligned the virtual address, 
whereas the new ones also ensure the physical address is aligned. This 
is required for the memory used for the MMU page tables, for example.



Mark Cave-Ayland - Senior Technical Architect
PostgreSQL - PostGIS
Sirius Corporation plc - control through freedom
t: +44 870 608 0063

Sirius Labs: http://www.siriusit.co.uk/labs

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