TTM placement & caching issue/questions

[Michel Dänzer]

On 04.09.2014 11:36, Jerome Glisse wrote:
> On Wed, Sep 03, 2014 at 10:31:18PM -0400, Jerome Glisse wrote:
>> On Thu, Sep 04, 2014 at 12:25:23PM +1000, Benjamin Herrenschmidt wrote:
>>> On Wed, 2014-09-03 at 22:07 -0400, Jerome Glisse wrote:
>>>
>>>> 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.

[...]

> +#else /* CONFIG_X86 */
> +int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t *placement)
> +{
> +	if (*placement & (TTM_PL_TT | TTM_PL_FLAG_SYSTEM)) {
> +		ttm->caching_state = tt_cached;
> +		*placement &= ~TTM_PL_MASK_CACHING;
> +		*placement |= TTM_PL_FLAG_CACHED;

NAK, this will break AGP on PowerMacs.


-- 
Earthling Michel Dänzer            |                  http://www.amd.com
Libre software enthusiast          |                Mesa and X developer