powerpc/dart_iommu: Support for 64-bit iommu bypass window on PCIe
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>
Mon, 30 Aug 2010 19:24:18 +0000 (19:24 +0000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Thu, 2 Sep 2010 04:07:32 +0000 (14:07 +1000)
commit8fb07c0444c37caa39a8df7c70a694c6211f2f57
tree1a8d1d5c3d30098822e9ca7f1931a136334641da
parent5b6e9ff6deb703b95fb355bb66d86096c1a2df09
powerpc/dart_iommu: Support for 64-bit iommu bypass window on PCIe

The PCI-Express bus off the U4/CPC945 bridge supports direct DMA to
all of memory, bypassing the DART iommu, for 64-bit capable devices.

This adds support for it on Bimini and Apple Quad G5's in order to
improve DMA performances of cards using that slot (the x16 graphics
slot). Tested with an Intel ixgbe 10GE card.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/sysdev/dart_iommu.c