freedreno: track batch/blit types

Add a bit of extra book-keeping about blits and back-blits (from
resource shadowing).  If the app uploads all mipmap levels, as opposed
to uploading the first level and then glGenerateMipmap(), we can discard
the back-blit (as opposed to being naive and shadowing the resource for
each mipmap level).  Also, after a normal blit, we might as well flush
the batch immediately, since there is not likely to be further rendering
to the surface.

Signed-off-by: Rob Clark <robdclark@gmail.com>

src/gallium/drivers/freedreno/freedreno_batch.h

@@ -93,7 +93,9 @@ struct fd_batch {
 		FD_BUFFER_ALL     = FD_BUFFER_COLOR | FD_BUFFER_DEPTH | FD_BUFFER_STENCIL,
 	} cleared, partial_cleared, restore, resolve;
 
-	bool needs_flush;
+	bool needs_flush : 1;
+	bool blit : 1;
+	bool back_blit : 1;      /* only blit so far is resource shadowing back-blit */
 
 	/* To decide whether to render to system memory, keep track of the
 	 * number of draws, and whether any of them require multisample,

src/gallium/drivers/freedreno/freedreno_context.h

@@ -161,16 +161,27 @@ struct fd_context {
 	 */
 	struct fd_batch *batch;
 
+	/* Are we in process of shadowing a resource? Used to detect recursion
+	 * in transfer_map, and skip unneeded synchronization.
+	 */
+	bool in_shadow : 1;
+
+	/* Ie. in blit situation where we no longer care about previous framebuffer
+	 * contents.  Main point is to eliminate blits from fd_try_shadow_resource().
+	 * For example, in case of texture upload + gen-mipmaps.
+	 */
+	bool in_blit : 1;
+
 	/* Keep track if WAIT_FOR_IDLE is needed for registers we need
 	 * to update via RMW:
 	 */
-	bool needs_wfi;
+	bool needs_wfi : 1;
 
 	/* Do we need to re-emit RB_FRAME_BUFFER_DIMENSION?  At least on a3xx
 	 * it is not a banked context register, so it needs a WFI to update.
 	 * Keep track if it has actually changed, to avoid unneeded WFI.
 	 * */
-	bool needs_rb_fbd;
+	bool needs_rb_fbd : 1;
 
 	struct pipe_scissor_state scissor;
 
@@ -244,17 +255,6 @@ struct fd_context {
 	bool cond_cond; /* inverted rendering condition */
 	uint cond_mode;
 
-	/* Are we in process of shadowing a resource? Used to detect recursion
-	 * in transfer_map, and skip unneeded synchronization.
-	 */
-	bool in_shadow;
-
-	/* Ie. in blit situation where we no longer care about previous framebuffer
-	 * contents.  Main point is to eliminate blits from fd_try_shadow_resource().
-	 * For example, in case of texture upload + gen-mipmaps.
-	 */
-	bool discard;
-
 	struct pipe_debug_callback debug;
 
 	/* GMEM/tile handling fxns: */

src/gallium/drivers/freedreno/freedreno_draw.c

@@ -84,15 +84,19 @@ fd_draw_vbo(struct pipe_context *pctx, const struct pipe_draw_info *info)
 		return;
 	}
 
-	if (ctx->discard) {
-		fd_batch_reset(ctx->batch);
-		ctx->discard = false;
+	if (ctx->in_blit) {
+		fd_batch_reset(batch);
+		ctx->dirty = ~0;
 	}
 
+	batch->blit = ctx->in_blit;
+	batch->back_blit = ctx->in_shadow;
+
 	/* NOTE: needs to be before resource_written(batch->query_buf), otherwise
 	 * query_buf may not be created yet.
 	 */
 	fd_hw_query_set_stage(batch, batch->draw, FD_STAGE_DRAW);
+
 	/*
 	 * Figure out the buffers/features we need:
 	 */
@@ -219,9 +223,9 @@ fd_clear(struct pipe_context *pctx, unsigned buffers,
 	if (!fd_render_condition_check(pctx))
 		return;
 
-	if (ctx->discard) {
-		fd_batch_reset(ctx->batch);
-		ctx->discard = false;
+	if (ctx->in_blit) {
+		fd_batch_reset(batch);
+		ctx->dirty = ~0;
 	}
 
 	/* for bookkeeping about which buffers have been cleared (and thus

src/gallium/drivers/freedreno/freedreno_resource.c

@@ -487,6 +487,12 @@ fd_resource_transfer_map(struct pipe_context *pctx,
 		 * to wait.
 		 */
 	} else if (!(usage & PIPE_TRANSFER_UNSYNCHRONIZED)) {
+		if ((usage & PIPE_TRANSFER_WRITE) && rsc->write_batch &&
+				rsc->write_batch->back_blit) {
+			/* if only thing pending is a back-blit, we can discard it: */
+			fd_batch_reset(rsc->write_batch);
+		}
+
 		/* If the GPU is writing to the resource, or if it is reading from the
 		 * resource and we're trying to write to it, flush the renders.
 		 */
@@ -1057,7 +1063,7 @@ fd_blitter_pipe_begin(struct fd_context *ctx, bool render_cond, bool discard)
 	if (ctx->batch)
 		fd_hw_query_set_stage(ctx->batch, ctx->batch->draw, FD_STAGE_BLIT);
 
-	ctx->discard = discard;
+	ctx->in_blit = discard;
 }
 
 static void
@@ -1065,6 +1071,7 @@ fd_blitter_pipe_end(struct fd_context *ctx)
 {
 	if (ctx->batch)
 		fd_hw_query_set_stage(ctx->batch, ctx->batch->draw, FD_STAGE_NULL);
+	ctx->in_blit = false;
 }
 
 static void

src/gallium/drivers/freedreno/freedreno_state.c

@@ -119,13 +119,28 @@ fd_set_framebuffer_state(struct pipe_context *pctx,
 	struct pipe_framebuffer_state *cso;
 
 	if (ctx->screen->reorder) {
-		struct fd_batch *batch;
-		if (likely(ctx->batch))
-			fd_hw_query_set_stage(ctx->batch, ctx->batch->draw, FD_STAGE_NULL);
+		struct fd_batch *batch, *old_batch = NULL;
+
+		fd_batch_reference(&old_batch, ctx->batch);
+
+		if (likely(old_batch))
+			fd_hw_query_set_stage(old_batch, old_batch->draw, FD_STAGE_NULL);
+
 		batch = fd_batch_from_fb(&ctx->screen->batch_cache, ctx, framebuffer);
 		fd_batch_reference(&ctx->batch, NULL);
 		ctx->batch = batch;
 		ctx->dirty = ~0;
+
+		if (old_batch && old_batch->blit && !old_batch->back_blit) {
+			/* for blits, there is not really much point in hanging on
+			 * to the uncommitted batch (ie. you probably don't blit
+			 * multiple times to the same surface), so we might as
+			 * well go ahead and flush this one:
+			 */
+			fd_batch_flush(old_batch);
+		}
+
+		fd_batch_reference(&old_batch, NULL);
 	} else {
 		DBG("%d: cbufs[0]=%p, zsbuf=%p", ctx->batch->needs_flush,
 				framebuffer->cbufs[0], framebuffer->zsbuf);