panfrost: Refactor blend descriptors

This commit does a fairly large cleanup of blend descriptors, although
there should not be any functional changes. In particular, we split
apart the Midgard and Bifrost blend descriptors, since they are
radically different. From there, we can identify that the Midgard
descriptor as previously written was really two render targets'
descriptors stuck together. From this observation, we split the Midgard
descriptor into what a single RT actually needs. This enables us to
correctly dump blending configuration for MRT samples on Midgard. It
also allows the Midgard and Bifrost blend code to peacefully coexist,
with runtime selection rather than a #ifdef. So, as a bonus, this will
help the future Bifrost effort, eliminating one major source of
compile-time architectural divergence.

Signed-off-by: Alyssa Rosenzweig <[email protected]>

1 files changed, 79 insertions, 76 deletions

diff --git a/src/gallium/drivers/panfrost/pandecode/decode.c b/src/gallium/drivers/panfrost/pandecode/decode.c
index 9936249e524..9d9b9b31bcd 100644
--- a/src/gallium/drivers/panfrost/pandecode/decode.c
+++ b/src/gallium/drivers/panfrost/pandecode/decode.c
@@ -857,12 +857,12 @@ pandecode_replay_stencil(const char *name, const struct mali_stencil_test *stenc
 }
 
 static void
-pandecode_replay_blend_equation(const struct mali_blend_equation *blend, const char *suffix)
+pandecode_replay_blend_equation(const struct mali_blend_equation *blend)
 {
         if (blend->zero1)
                 pandecode_msg("Blend zero tripped: %X\n", blend->zero1);
 
-        pandecode_log(".blend_equation%s = {\n", suffix);
+        pandecode_log(".equation = {\n");
         pandecode_indent++;
 
         pandecode_prop("rgb_mode = 0x%X", blend->rgb_mode);
@@ -876,6 +876,69 @@ pandecode_replay_blend_equation(const struct mali_blend_equation *blend, const c
         pandecode_log("},\n");
 }
 
+static mali_ptr
+pandecode_bifrost_blend(void *descs, int job_no, int rt_no)
+{
+        struct bifrost_blend_rt *b =
+                ((struct bifrost_blend_rt *) descs) + rt_no;
+
+        pandecode_log("struct bifrost_blend_rt blend_rt_%d_%d = {\n", job_no, rt_no);
+        pandecode_indent++;
+
+        pandecode_prop("unk1 = 0x%" PRIx32, b->unk1);
+        /* TODO figure out blend shader enable bit */
+        pandecode_replay_blend_equation(&b->equation);
+        pandecode_prop("unk2 = 0x%" PRIx16, b->unk2);
+        pandecode_prop("index = 0x%" PRIx16, b->index);
+        pandecode_prop("shader = 0x%" PRIx32, b->shader);
+
+        pandecode_indent--;
+        pandecode_log("},\n");
+        
+        return 0;
+}
+
+static mali_ptr
+pandecode_midgard_blend(union midgard_blend *blend, bool is_shader)
+{
+        pandecode_log(".blend = {\n");
+        pandecode_indent++;
+
+        if (is_shader) {
+                pandecode_replay_shader_address("shader", blend->shader);
+        } else {
+                pandecode_replay_blend_equation(&blend->equation);
+        }
+
+        pandecode_indent--;
+        pandecode_log("},\n");
+
+        /* Return blend shader to disassemble if present */
+        return is_shader ? (blend->shader & ~0xF) : 0;
+}
+
+static mali_ptr
+pandecode_midgard_blend_mrt(void *descs, int job_no, int rt_no)
+{
+        struct midgard_blend_rt *b =
+                ((struct midgard_blend_rt *) descs) + rt_no;
+
+        /* Flags determine presence of blend shader */
+        bool is_shader = (b->flags & 0xF) >= 0x2;
+
+        pandecode_log("struct midgard_blend_rt blend_rt_%d_%d = {\n", job_no, rt_no);
+        pandecode_indent++;
+
+        pandecode_prop("flags = 0x%" PRIx64, b->flags); 
+
+        mali_ptr shader = pandecode_midgard_blend(&b->blend, is_shader);
+
+        pandecode_indent--;
+        pandecode_log("};\n");
+
+        return shader;
+}
+
 static int
 pandecode_replay_attribute_meta(int job_no, int count, const struct mali_vertex_tiler_postfix *v, bool varying, char *suffix)
 {
@@ -1248,95 +1311,35 @@ pandecode_replay_vertex_tiler_postfix_pre(const struct mali_vertex_tiler_postfix
 
                 pandecode_prop("unknown2_8 = 0x%" PRIx32, s->unknown2_8);
 
-                bool blend_shader = false;
-
                 if (!is_bifrost) {
-                        if (s->unknown2_3 & MALI_HAS_BLEND_SHADER) {
-                                blend_shader = true;
-                                pandecode_replay_shader_address("blend_shader", s->blend_shader);
-                        } else {
-                                pandecode_replay_blend_equation(&s->blend_equation, "");
-                        }
+                        /* TODO: Blend shaders routing/disasm */
+
+                        pandecode_midgard_blend(&s->blend, false);
                 }
 
                 pandecode_indent--;
                 pandecode_log("};\n");
 
-                /* MRT blend fields are used whenever MFBD is used */
+                /* MRT blend fields are used whenever MFBD is used, with
+                 * per-RT descriptors */
 
                 if (job_type == JOB_TYPE_TILER) {
-                        pandecode_log("struct mali_blend_meta blend_meta_%d[] = {\n",
-                                    job_no);
-                        pandecode_indent++;
-
-                        int i;
-
-                        for (i = 0; i < 4; i++) {
-                                const struct mali_blend_meta *b = &s->blend_meta[i];
-                                pandecode_log("{\n");
-                                pandecode_indent++;
-
-#ifndef BIFROST
-                                pandecode_prop("unk1 = 0x%" PRIx64, b->unk1);
-
-                                /* Depending on unk1, we determine if there's a
-                                 * blend shader */
-
-                                if ((b->unk1 & 0xF) >= 0x2) {
-                                        blend_shader = true;
-                                        pandecode_replay_shader_address("blend_shader", b->blend_shader);
-                                } else {
-                                        pandecode_replay_blend_equation(&b->blend_equation_1, "_1");
-                                }
-
-                                /* This is always an equation, I think. If
-                                 * there's a shader, it just defaults to
-                                 * REPLACE (0x122) */
-                                pandecode_replay_blend_equation(&b->blend_equation_2, "_2");
-
-                                if (b->zero2) {
-                                        pandecode_msg("blend zero tripped\n");
-                                        pandecode_prop("zero2 = 0x%x", b->zero2);
-                                }
+                        void* blend_base = (void *) (s + 1);
 
-#else
+                        for (unsigned i = 0; i < 4; i++) {
+                                mali_ptr shader = 0;
 
-                                pandecode_prop("unk1 = 0x%" PRIx32, b->unk1);
-                                /* TODO figure out blend shader enable bit */
-                                pandecode_replay_blend_equation(&b->blend_equation);
-                                pandecode_prop("unk2 = 0x%" PRIx16, b->unk2);
-                                pandecode_prop("index = 0x%" PRIx16, b->index);
-                                pandecode_prop("unk3 = 0x%" PRIx32, b->unk3);
-#endif
-
-                                pandecode_indent--;
-                                pandecode_log("},\n");
-
-#ifdef BIFROST
-                                if (b->unk2 == 3)
-                                        break;
-#else
-                                /* TODO: What's this supposed to be? */
-                                if (b->unk1 & 0x200)
-                                        break;
-#endif
+                                if (is_bifrost)
+                                        shader = pandecode_bifrost_blend(blend_base, job_no, i);
+                                else
+                                        shader = pandecode_midgard_blend_mrt(blend_base, job_no, i);
 
+                                if (shader)
+                                        pandecode_shader_disassemble(shader, job_no, job_type, false);
                         }
-
-                        pandecode_indent--;
-                        pandecode_log("};\n");
-
-                        /* This needs to be uploaded right after the
-                         * shader_meta since it's technically part of the same
-                         * (variable-size) structure.
-                         */
                 }
 
                 pandecode_shader_disassemble(shader_ptr, job_no, job_type, is_bifrost);
-
-                if (!is_bifrost && blend_shader)
-                        pandecode_shader_disassemble(s->blend_shader & ~0xF, job_no, job_type, false);
-
         } else
                 pandecode_msg("<no shader>\n");