tree 68a452bd8e9d07e9a28cef63ee3b72e0319635da
parent 79e25bac124a7d1d7bf966f06dd9398a1b5f3d20
author Mark Nelson <markn@au1.ibm.com> 1216386214 +1000
committer Benjamin Herrenschmidt <benh@kernel.crashing.org> 1216687176 +1000

powerpc/cell: Add DMA_ATTR_WEAK_ORDERING dma attribute and use in Cell IOMMU code

Introduce a new dma attriblue DMA_ATTR_WEAK_ORDERING to use weak ordering
on DMA mappings in the Cell processor. Add the code to the Cell's IOMMU
implementation to use this code.

Dynamic mappings can be weakly or strongly ordered on an individual basis
but the fixed mapping has to be either completely strong or completely weak.
This is currently decided by a kernel boot option (pass iommu_fixed=weak
for a weakly ordered fixed linear mapping, strongly ordered is the default).

Signed-off-by: Mark Nelson <markn@au1.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>