From d15133859424e73ed892ab05c2bdbb76157da517 Mon Sep 17 00:00:00 2001 From: Neil Roberts Date: Wed, 18 Nov 2015 18:14:33 +0100 Subject: [PATCH] i965/gen9: Allow fast clear for MSRT formats matching render Previously fast clear was disallowed on Gen9 for MSRTs with the claim that some formats don't work but we didn't understand why. On further investigation it seems the formats that don't work are the ones where the render surface format is being overriden to a different format than the one used for texturing. The one used for texturing is not actually a renderable format. It arguably makes sense that the sampler hardware doesn't handle the fast color correctly in these cases because it shouldn't be possible to end up with a fast cleared surface that is non-renderable. This patch changes the limitation to prevent fast clear for surfaces where the format for rendering is overriden. Reviewed-by: Ben Widawsky --- src/mesa/drivers/dri/i965/brw_meta_fast_clear.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c b/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c index f1920b2edce..cf0e56b5244 100644 --- a/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c +++ b/src/mesa/drivers/dri/i965/brw_meta_fast_clear.c @@ -50,6 +50,7 @@ #include "brw_defines.h" #include "brw_context.h" #include "brw_draw.h" +#include "brw_state.h" #include "intel_fbo.h" #include "intel_batchbuffer.h" @@ -573,11 +574,17 @@ brw_meta_fast_clear(struct brw_context *brw, struct gl_framebuffer *fb, if (brw->gen < 7) clear_type = REP_CLEAR; - /* Certain formats have unresolved issues with sampling from the MCS - * buffer on Gen9. This disables fast clears altogether for MSRTs until - * we can figure out what's going on. + /* If we're mapping the render format to a different format than the + * format we use for texturing then it is a bit questionable whether it + * should be possible to use a fast clear. Although we only actually + * render using a renderable format, without the override workaround it + * wouldn't be possible to have a non-renderable surface in a fast clear + * state so the hardware probably legitimately doesn't need to support + * this case. At least on Gen9 this really does seem to cause problems. */ - if (brw->gen >= 9 && irb->mt->num_samples > 1) + if (brw->gen >= 9 && + brw_format_for_mesa_format(irb->mt->format) != + brw->render_target_format[irb->mt->format]) clear_type = REP_CLEAR; if (irb->mt->fast_clear_state == INTEL_FAST_CLEAR_STATE_NO_MCS) -- 2.30.2