[PATCH 1/1] powerpc: Force 32 bit MSIs on systems lacking firmware support

[Benjamin Herrenschmidt]

On Wed, 2013-05-22 at 14:36 +1000, Michael Ellerman wrote:
> This is basically baking knowledge of phyp's address layout into the
> kernel right? Which is OK, but it needs a big fat comment describing
> exactly what it's doing and why it's safe.

Not pHyp really but the HW, basically this should work with any IODA1
host bridge (P7IOC, Torrent, ...). The "assumption" here is that RTAS
MSI + PCIe Gen2 == IODA1 :-)

Cheers,
Ben.