[PATCH] powerpc: Fix problems with 32bit PPC's running with more than 2GB of RAM

Benjamin Herrenschmidt benh at kernel.crashing.org
Thu Jul 10 06:39:39 EST 2008


On Wed, 2008-07-09 at 16:22 -0400, Josh Boyer wrote:
> On Thu, 10 Jul 2008 06:02:38 +1000
> Benjamin Herrenschmidt <benh at kernel.crashing.org> wrote:
> 
> > On Wed, 2008-07-09 at 15:44 +0200, Stefan Roese wrote:
> > > This patch enables 32bit PPC's (with 36bit physical address space, e.g.
> > > IBM/AMCC PPC44x) to run with more than 2GB of RAM. Mostly its just
> > > replacing types (unsigned long -> phys_addr_t).
> > > 
> > > Tested on an AMCC Katmai with 4GB of DDR2.
> > > 
> > > Signed-off-by: Stefan Roese <sr at denx.de>
> > 
> > But DMAs will break no ?
> 
> How?

Hrm... forget it. It's fine up to 4G of RAM... (ie. as long as DMA is
below 32 bits).

Ben.





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