[PARISC] Update sba_iommu from parisc tree

[PARISC] Update sba_iommu from parisc tree

revert use of %%sr0 in fdc asm.
Thanks to Joel Soete for pointing out this oversight.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
2.6.14-rc2-pa3 move "sync" outside the main loop that fills IO Pdir.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
remove explicit use of sr0 in fdc ops.
Thanks to Joel Soete for reminding me were I added those...

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
2.6.14-rc2-pa2 - make SBA more anal about invalidating pdir entries

Previous code cleared the valid flag a pdir entry but it did NOT
guarantee this change was visible to the PDIR before writing
the PCOM register. Ie the SBA could pick up a stale entry if
the write happened to hit the SBA before the cacheline was flushed
from the cache.

Long term, I think I want to make this a compile time flag.
Developement tree should enable anal pdir checking by default
and Debian can disable it with either a CONFIG option
or one-line patch. fdc/sync options can only negatively affect
performance though I haven't measure how much yet.
If someone can run netperf TCP_RR across gige and compare
-pa1 and -pa2, that would be sufficient.

Cleaned up the use of "fdc" to make sure it's using "kernel"
space id (specify sr0 but maps to sr4-7). It seems a bit fragile
to assume "sr1" gets loaded with KERNEL_SPACE which is how the
code works today.

Tested on 32 and 64-bit SMP kernels on j6k.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
remove PDC_NARROW from SBA and document history of PDC_NARROW a bit.
It will still show up in an older kernel's .config file.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
if/ifdef cleanups from Joel Soete.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
2.6.12-rc4-pa2  fix 32-bit support for Astro platforms
o Since my last SBA code change, SBA could allocate more than 1GB of IOVA
  space on Astro boxes with more than 1GB of RAM when running 32-bit kernel.
  This is bad since IOMMU can only talk to the first 1GB at most.
  Kudos to jejb for quickly spotting that bug.

o jejb also noted SBA should *always* reject DMA masks > 32-bits since
  DMA-mapping.txt indicates caller should try again with 32-bits.

o off-by-one error when comparing the mask to IOVA space size.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>