On 6/21/22 22:00, Robert Beckett wrote:
By default i915_ttm_cache_level() decides I915_CACHE_LLC if HAS_SNOOP. This is divergent from existing backends code which only considers HAS_LLC. Testing shows that trusting snooping on gen5- is unreliable and bsw via ggtt mappings, so limit DGFX for now and maintain previous behaviour.
Yeah, IIRC Matthew mentioned that HAS_SNOOP() can be overridden in various ways, but not on DGFX, (at least not for DG1). So this looks correct to me.
Signed-off-by: Robert Beckett bob.beckett@collabora.com
Reviewed-by: Thomas Hellström thomas.hellstrom@linux.intel.com
drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c index 4c1de0b4a10f..40249fa28a7a 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c @@ -46,7 +46,9 @@ static enum i915_cache_level i915_ttm_cache_level(struct drm_i915_private *i915, struct ttm_resource *res, struct ttm_tt *ttm) {
- return ((HAS_LLC(i915) || HAS_SNOOP(i915)) &&
- bool can_snoop = HAS_SNOOP(i915) && IS_DGFX(i915);
- return ((HAS_LLC(i915) || can_snoop) && !i915_ttm_gtt_binds_lmem(res) && ttm->caching == ttm_cached) ? I915_CACHE_LLC : I915_CACHE_NONE;