Re: TTM placement & caching issue/questions

On Wed, 2014-09-03 at 22:36 -0400, Jerome Glisse wrote:

On Wed, Sep 03, 2014 at 10:31:18PM -0400, Jerome Glisse wrote:

quoted

On Thu, Sep 04, 2014 at 12:25:23PM +1000, Benjamin Herrenschmidt wrote:

quoted

On Wed, 2014-09-03 at 22:07 -0400, Jerome Glisse wrote:

quoted

So in the meantime the attached patch should work, it just silently ignore
the caching attribute request on non x86 instead of pretending that things
are setup as expected and then latter the radeon ou nouveau hw unsetting
the snoop bit.

It's not tested but i think it should work.

I'm still getting placements with !CACHED going from bo_memcpy in
ttm_io_prot() though ... I'm looking at filtering the placement
attributes instead.

Ben.

Ok so this one should do the trick.

Ok final version ... famous last word.

Minus a couple of obvious typos that prevent if from building, it seems
to do the trick for me with the AST driver, no more bad mappings.

I'll still send a patch that catches the incorrect mapping attempts
inside ttm_io_prot() and warns to help future debugging and avoid
"random" behaviour. (I need to fix other things in the powerpc code
in there anyway).

Cheers,
Ben.