Most of the time, it doesn't make much of a difference whether we use the
blitter or the render pipeline. However, on the GpuTest triangle test from
~4000FPS to ~6000FPS on my HSW desktop. No, that is not a typo. We also
see improvement on several Bay Trail benchmarks.
Signed-off-by: Jason Ekstrand <jason.ekstr...@intel.com>
---
src/mesa/drivers/dri/i965/brw_meta_fast_clear.c | 37 +++++++++++++++++++++++++
1 file changed, 37 insertions(+)
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 b4e75a7..1c8b542 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_draw.h"
#include "intel_fbo.h"
#include "intel_batchbuffer.h"
+#include "intel_blit.h"
#include "brw_blorp.h"
@@ -404,6 +405,39 @@ use_rectlist(struct brw_context *brw, bool enable)
brw->state.dirty.brw |= BRW_NEW_FRAGMENT_PROGRAM;
}
+/* This function attempts to do a fast clear using the blitter.
+ *
+ * The official documentation describes how to do a fast clear using the
+ * render pipeline by setting various bits and using a replicated send
+ * instruction with a rectlist. Doing fast clears with the blitter isn't
+ * documented to work, but in practice it works just fine. Doing it this
+ * way allows us to avoid touching GL state and just use the blit pipeline.
+ */
+static bool
+try_fast_clear_with_blitter(struct brw_context *brw,
+ struct intel_mipmap_tree *mt)
+{
+ /* Out of bounds for the blitter */
+ if (mt->mcs_mt->pitch > INT16_MAX || mt->mcs_mt->total_height > INT16_MAX)
+ return false;
+
+ assert(mt->mcs_mt->tiling == I915_TILING_Y);
+ assert(mt->mcs_mt->cpp <= 4);
+
+ int full_width = mt->mcs_mt->pitch / mt->mcs_mt->cpp;
+ if (!intel_emit_color_blit(brw, mt->mcs_mt->cpp, 0xffffffff,
+ mt->mcs_mt->pitch, mt->mcs_mt->bo,
+ mt->mcs_mt->offset, mt->mcs_mt->tiling,
+ 0, 0,
+ mt->mcs_mt->pitch / mt->mcs_mt->cpp,
+ mt->mcs_mt->total_height,
+ true, true))
+ return false;
+
+ mt->fast_clear_state = INTEL_FAST_CLEAR_STATE_CLEAR;
+ return true;
+}
+
bool
brw_meta_fast_clear(struct brw_context *brw, struct gl_framebuffer *fb,
GLbitfield buffers, bool partial_clear)
@@ -503,6 +537,9 @@ brw_meta_fast_clear(struct brw_context *brw, struct
gl_framebuffer *fb,
if (irb->mt->fast_clear_state == INTEL_FAST_CLEAR_STATE_CLEAR)
continue;
+ if (try_fast_clear_with_blitter(brw, irb->mt))
+ continue;
+
/* Set fast_clear_state to RESOLVED so we don't try resolve them when
* we draw, in case the mt is also bound as a texture.
*/
--
2.1.0
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
