From e7a7679b9a77bd4b4300c19bc6b3365756f03c5b Mon Sep 17 00:00:00 2001 From: Alyssa Rosenzweig Date: Fri, 27 May 2022 08:46:46 -0400 Subject: [PATCH] panfrost: Set overdraw_alpha[01] flags These basically correspond to the alpha_zero_nop and alpha_one_store flags we already compute and set. Except those flags don't exist on Valhall, so these need to be used instead (on Bifrost, in addition .. unclear why the duplication on Bifrost). Set these flags when we can. Ostensibly this is for performance (neglible improvement on glmark2 score), but mostly I want to get us using the hardware optimally. Signed-off-by: Alyssa Rosenzweig Part-of: --- src/gallium/drivers/panfrost/pan_cmdstream.c | 40 ++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/src/gallium/drivers/panfrost/pan_cmdstream.c b/src/gallium/drivers/panfrost/pan_cmdstream.c index f9b89e0e29f..35fbb0af0fc 100644 --- a/src/gallium/drivers/panfrost/pan_cmdstream.c +++ b/src/gallium/drivers/panfrost/pan_cmdstream.c @@ -315,6 +315,32 @@ pack_blend_constant(enum pipe_format format, float cons) return unorm << (16 - chan_size); } +/* + * Determine whether to set the respective overdraw alpha flag. + * + * The overdraw alpha=1 flag should be set when alpha=1 implies full overdraw, + * equivalently, all enabled render targets have alpha_one_store set. Likewise, + * overdraw alpha=0 should be set when alpha=0 implies no overdraw, + * equivalently, all enabled render targets have alpha_zero_nop set. + */ +static bool +panfrost_overdraw_alpha(const struct panfrost_context *ctx, bool zero) +{ + const struct panfrost_blend_state *so = ctx->blend; + + for (unsigned i = 0; i < ctx->pipe_framebuffer.nr_cbufs; ++i) { + const struct pan_blend_info info = so->info[i]; + + bool enabled = ctx->pipe_framebuffer.cbufs[i] && info.no_colour; + bool flag = zero ? info.alpha_zero_nop : info.alpha_one_store; + + if (enabled && !flag) + return false; + } + + return true; +} + static void panfrost_emit_blend(struct panfrost_batch *batch, void *rts, mali_ptr *blend_shaders) { @@ -468,6 +494,10 @@ pan_merge_empty_fs(struct mali_renderer_state_packed *rsd) cfg.properties.allow_forward_pixel_to_kill = true; cfg.properties.allow_forward_pixel_to_be_killed = true; cfg.properties.zs_update_operation = MALI_PIXEL_KILL_STRONG_EARLY; + + /* Alpha isn't written so these are vacuous */ + cfg.multisample_misc.overdraw_alpha0 = true; + cfg.multisample_misc.overdraw_alpha1 = true; #else cfg.shader.shader = 0x1; cfg.properties.work_register_count = 1; @@ -580,6 +610,9 @@ panfrost_prepare_fs_state(struct panfrost_context *ctx, */ cfg.properties.point_sprite_coord_origin_max_y = (rast->sprite_coord_mode == PIPE_SPRITE_COORD_LOWER_LEFT); + + cfg.multisample_misc.overdraw_alpha0 = panfrost_overdraw_alpha(ctx, 0); + cfg.multisample_misc.overdraw_alpha1 = panfrost_overdraw_alpha(ctx, 1); #endif cfg.stencil_mask_misc.alpha_to_coverage = alpha_to_coverage; @@ -3283,6 +3316,9 @@ panfrost_emit_draw(void *out, cfg.blend_count = MAX2(batch->key.nr_cbufs, 1); cfg.alpha_to_coverage = ctx->blend->base.alpha_to_coverage; + cfg.overdraw_alpha0 = panfrost_overdraw_alpha(ctx, 0); + cfg.overdraw_alpha1 = panfrost_overdraw_alpha(ctx, 1); + panfrost_emit_shader(batch, &cfg.shader, PIPE_SHADER_FRAGMENT, batch->rsd[PIPE_SHADER_FRAGMENT], batch->tls.gpu); @@ -3302,6 +3338,10 @@ panfrost_emit_draw(void *out, /* No shader => no shader side effects */ cfg.allow_forward_pixel_to_be_killed = true; + + /* Alpha isn't written so these are vacuous */ + cfg.overdraw_alpha0 = true; + cfg.overdraw_alpha1 = true; } #else cfg.position = pos;