tree 2711786140a63cbbbf7154ac1e5d2f1bc11e2b86
parent f2b115e69d46344ae7afcaad5823496d2a0d8650
author David Woodhouse <dwmw2@infradead.org> 1259751605 +0000
committer Eric Anholt <eric@anholt.net> 1260228544 -0800

agp/intel-agp: Clear entire GTT on startup

Some BIOSes fail to initialise the GTT, which will cause DMA faults when
the IOMMU is enabled. We need to clear the whole thing to point at the
scratch page, not just the part that Linux is going to use.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
[anholt: Note that this may also help with stability in the presence of
driver bugs, by not drawing to memory we don't own]
Signed-off-by: Eric Anholt <eric@anholt.net>