[PATCH] powerpc: Fix problems with 32bit PPC's running with more than 2GB of RAM
Benjamin Herrenschmidt
benh at kernel.crashing.org
Sat Jul 12 13:33:54 EST 2008
> Are you *sure* you can see all 4GB? I thought we lost some of the 32-
> bit PCI address space for PCI IO...... Disclaimer: I'm no expert on
> PCI :)
You are right. I didn't think that through when I replied. We do lose
some of it for MMIO (not IO). So we cannot really go all the way to 4G
because we can't DMA to all of it, right.
> FYI, I'm *very* close to having swiotlb fully functional on powerpc to
> support larger RAM - I am able to boot with 6GB on 8641 right now.
> There are some bugs that I'm still shaking out - I hope to push this
> out in the next couple of weeks.
That won't make .27 then ?
Cheers,
Ben.
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