Revert "pseries/iommu: Remove DDW on kexec"
authorNishanth Aravamudan <nacc@linux.vnet.ibm.com>
Fri, 10 Jan 2014 23:10:41 +0000 (15:10 -0800)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Wed, 15 Jan 2014 02:46:45 +0000 (13:46 +1100)
commit97e7dc523acaa335d44517b06ef5609b3ee65c6a
tree927bb7eede2a0031a5bb34e88cbe6654e71c85d2
parentae69e1eddc646ff8dc1d5439005d1f82c33f9ae7
Revert "pseries/iommu: Remove DDW on kexec"

After reverting 25ebc45b93452d0bc60271f178237123c4b26808
("powerpc/pseries/iommu: remove default window before attempting DDW
manipulation"), we no longer remove the base window in enable_ddw.
Therefore, we no longer need to reset the DMA window state in
find_existing_ddw_windows(). We can instead go back to what was done
before, which simply reuses the previous configuration, if any. Further,
this removes the final caller of the reset-pe-dma-windows call, so
remove those functions.

This fixes an EEH on kdump with the ipr driver. The EEH occurs, because
the initcall removes the DDW configuration (64-bit DMA window), but
doesn't ensure the ops are via the IOMMU -- a DMA operation occurs
during probe (still investigating this) and we EEH.

This reverts commit 14b6f00f8a4fdec5ccd45a0710284de301a61628.

Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/platforms/pseries/iommu.c