From d32d4acf681ba685e770f409b81d34b4ec9f8a62 Mon Sep 17 00:00:00 2001 From: Alyssa Rosenzweig Date: Thu, 21 Nov 2019 08:43:53 -0500 Subject: [PATCH] pan/midgard: Add LOD bias/clamp lowering We fetch the info with the new intrinsic and lower with ALU ops for txl instructions, which seemingly correspond to "TEXGRD" instructions (what we call textureLod). Signed-off-by: Alyssa Rosenzweig Reviewed-by: Tomeu Vizoso --- src/panfrost/Makefile.sources | 3 +- src/panfrost/midgard/compiler.h | 2 + src/panfrost/midgard/meson.build | 1 + src/panfrost/midgard/midgard_errata_lod.c | 98 +++++++++++++++++++++++ 4 files changed, 103 insertions(+), 1 deletion(-) create mode 100644 src/panfrost/midgard/midgard_errata_lod.c diff --git a/src/panfrost/Makefile.sources b/src/panfrost/Makefile.sources index 5b2535bc42a..1dcb0bd2d02 100644 --- a/src/panfrost/Makefile.sources +++ b/src/panfrost/Makefile.sources @@ -43,6 +43,7 @@ midgard_FILES := \ midgard/midgard_ra.c \ midgard/midgard_ra_pipeline.c \ midgard/midgard_schedule.c \ + midgard/midgard_errata_lod.c \ midgard/mir.c \ midgard/mir_promote_uniforms.c @@ -56,4 +57,4 @@ pandecode_FILES := \ pandecode/decode.h \ pandecode/pan_pretty_print.c \ pandecode/pan_pretty_print.h \ - pandecode/public.h \ No newline at end of file + pandecode/public.h diff --git a/src/panfrost/midgard/compiler.h b/src/panfrost/midgard/compiler.h index 7a203da902a..f2fc5d36146 100644 --- a/src/panfrost/midgard/compiler.h +++ b/src/panfrost/midgard/compiler.h @@ -635,6 +635,8 @@ void emit_binary_bundle( bool nir_undef_to_zero(nir_shader *shader); +void midgard_nir_lod_errata(nir_shader *shader); + /* Optimizations */ bool midgard_opt_copy_prop(compiler_context *ctx, midgard_block *block); diff --git a/src/panfrost/midgard/meson.build b/src/panfrost/midgard/meson.build index e6fa2019bb0..fcb3089c6e2 100644 --- a/src/panfrost/midgard/meson.build +++ b/src/panfrost/midgard/meson.build @@ -36,6 +36,7 @@ libpanfrost_midgard_files = files( 'midgard_opt_invert.c', 'midgard_opt_float.c', 'midgard_opt_perspective.c', + 'midgard_errata_lod.c', 'disassemble.c', 'lcra.c' ) diff --git a/src/panfrost/midgard/midgard_errata_lod.c b/src/panfrost/midgard/midgard_errata_lod.c new file mode 100644 index 00000000000..55e2b230cb6 --- /dev/null +++ b/src/panfrost/midgard/midgard_errata_lod.c @@ -0,0 +1,98 @@ +/* + * Copyright (C) 2019 Collabora, Ltd. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "compiler/nir/nir.h" +#include "compiler/nir/nir_builder.h" + +void midgard_nir_lod_errata(nir_shader *shader); + +/* Workarounds errata pertaining to early Midgard chips where the settings for + * min_lod/max_lod/lod_bias are ignored in the sampler descriptor when + * texturing with a textureLod instruction. The workaround is to load these + * constants in as system values and perform the bias/clamp in the shader. + */ + +static void +mir_lod_errata_body(nir_builder *b, nir_tex_instr *tex) +{ + /* The errata only applies to textureLod ("TEXGRD") */ + if (tex->op != nir_texop_txl) + return; + + /* Let's grab the sampler parameters */ + nir_intrinsic_instr *l = nir_intrinsic_instr_create(b->shader, + nir_intrinsic_load_sampler_lod_parameters_pan); + l->num_components = 3; + nir_ssa_dest_init(&l->instr, &l->dest, 3, 32, NULL); + + /* TODO: Indirect samplers, separate sampler objects XXX */ + nir_src idx = nir_src_for_ssa(nir_imm_int(b, tex->texture_index)); + nir_src_copy(&l->src[0], &idx, l); + + nir_builder_instr_insert(b, &l->instr); + nir_ssa_def *params = &l->dest.ssa; + + /* Extract the individual components */ + nir_ssa_def *min_lod = nir_channel(b, params, 0); + nir_ssa_def *max_lod = nir_channel(b, params, 1); + nir_ssa_def *lod_bias = nir_channel(b, params, 2); + + /* Rewrite the LOD with bias/clamps. Order sensitive. */ + for (unsigned i = 0; i < tex->num_srcs; i++) { + if (tex->src[i].src_type != nir_tex_src_lod) + continue; + + nir_ssa_def *lod = nir_ssa_for_src(b, tex->src[i].src, 1); + + nir_ssa_def *biased = nir_fadd(b, lod, lod_bias); + nir_ssa_def *clamped = nir_fmin(b, + nir_fmax(b, biased, min_lod), max_lod); + + nir_instr_rewrite_src(&tex->instr, &tex->src[i].src, + nir_src_for_ssa(clamped)); + } +} + +void +midgard_nir_lod_errata(nir_shader *shader) +{ + nir_foreach_function(function, shader) { + if (!function->impl) continue; + + nir_builder b; + nir_builder_init(&b, function->impl); + + nir_foreach_block(block, function->impl) { + nir_foreach_instr_safe(instr, block) { + if (instr->type != nir_instr_type_tex) continue; + + nir_tex_instr *tex = nir_instr_as_tex(instr); + b.cursor = nir_before_instr(instr); + mir_lod_errata_body(&b, tex); + } + } + + nir_metadata_preserve(function->impl, nir_metadata_block_index | nir_metadata_dominance); + + } +} -- 2.30.2