pan/bi: Use canonical name for FAU RAM sources

The uniform_constant field and BIFROST_SRC_CONST_{LO,HI} definitions
seem to imply that those only deal with embedded constants. Let's
rename them to reflect the fact that they actually encode accesses to
the Fast-Access-Uniform RAM.

Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7151>

5 files changed, 49 insertions, 48 deletions

diff --git a/src/panfrost/bifrost/bi_pack.c b/src/panfrost/bifrost/bi_pack.c
index e1d0a4ac83d..195cc72f0ef 100644
--- a/src/panfrost/bifrost/bi_pack.c
+++ b/src/panfrost/bifrost/bi_pack.c
@@ -115,17 +115,18 @@ bi_constant_field(unsigned idx)
 }
 
 static bool
-bi_assign_uniform_constant_single(
-                bi_registers *regs,
-                bi_clause *clause,
-                bi_instruction *ins, bool assigned, bool fast_zero)
+bi_assign_fau_idx_single(bi_registers *regs,
+                         bi_clause *clause,
+                         bi_instruction *ins,
+                         bool assigned,
+                         bool fast_zero)
 {
         if (!ins)
                 return assigned;
 
         if (ins->type == BI_BLEND) {
                 assert(!assigned);
-                regs->uniform_constant = 0x8;
+                regs->fau_idx = 0x8;
                 return true;
         }
 
@@ -140,10 +141,10 @@ bi_assign_uniform_constant_single(
                 /* Build the constant */
                 unsigned C = bi_constant_field(idx) | lo;
 
-                if (assigned && regs->uniform_constant != C)
-                        unreachable("Mismatched uniform/const field: branch");
+                if (assigned && regs->fau_idx != C)
+                        unreachable("Mismatched fau_idx: branch");
 
-                regs->uniform_constant = C;
+                regs->fau_idx = C;
                 return true;
         }
 
@@ -163,25 +164,25 @@ bi_assign_uniform_constant_single(
                         unsigned lo = clause->constants[idx] & 0xF;
                         unsigned f = bi_constant_field(idx) | lo;
 
-                        if (assigned && regs->uniform_constant != f)
+                        if (assigned && regs->fau_idx != f)
                                 unreachable("Mismatched uniform/const field: imm");
 
-                        regs->uniform_constant = f;
-                        ins->src[s] = BIR_INDEX_PASS | (hi ? BIFROST_SRC_CONST_HI : BIFROST_SRC_CONST_LO);
+                        regs->fau_idx = f;
+                        ins->src[s] = BIR_INDEX_PASS | (hi ? BIFROST_SRC_FAU_HI : BIFROST_SRC_FAU_LO);
                         assigned = true;
                 } else if (ins->src[s] & BIR_INDEX_ZERO && (ins->type == BI_LOAD_UNIFORM || ins->type == BI_LOAD_VAR)) {
                         /* XXX: HACK UNTIL WE HAVE HI MATCHING DUE TO OVERFLOW XXX */
-                        ins->src[s] = BIR_INDEX_PASS | BIFROST_SRC_CONST_HI;
+                        ins->src[s] = BIR_INDEX_PASS | BIFROST_SRC_FAU_HI;
                 } else if (ins->src[s] & BIR_INDEX_ZERO && !fast_zero) {
                         /* FMAs have a fast zero slot, ADD needs to use the
                          * uniform/const slot's special 0 mode handled here */
                         unsigned f = 0;
 
-                        if (assigned && regs->uniform_constant != f)
+                        if (assigned && regs->fau_idx != f)
                                 unreachable("Mismatched uniform/const field: 0");
 
-                        regs->uniform_constant = f;
-                        ins->src[s] = BIR_INDEX_PASS | BIFROST_SRC_CONST_LO;
+                        regs->fau_idx = f;
+                        ins->src[s] = BIR_INDEX_PASS | BIFROST_SRC_FAU_LO;
                         assigned = true;
                 } else if (ins->src[s] & BIR_INDEX_ZERO && fast_zero) {
                         ins->src[s] = BIR_INDEX_PASS | BIFROST_SRC_STAGE;
@@ -194,15 +195,14 @@ bi_assign_uniform_constant_single(
 }
 
 static void
-bi_assign_uniform_constant(
-                bi_clause *clause,
-                bi_registers *regs,
-                bi_bundle bundle)
+bi_assign_fau_idx(bi_clause *clause,
+                  bi_registers *regs,
+                  bi_bundle bundle)
 {
         bool assigned =
-                bi_assign_uniform_constant_single(regs, clause, bundle.fma, false, true);
+                bi_assign_fau_idx_single(regs, clause, bundle.fma, false, true);
 
-        bi_assign_uniform_constant_single(regs, clause, bundle.add, assigned, false);
+        bi_assign_fau_idx_single(regs, clause, bundle.add, assigned, false);
 }
 
 /* Assigns a slot for reading, before anything is written */
@@ -395,7 +395,7 @@ bi_pack_registers(bi_registers regs)
 
         s.reg2 = regs.slot[2];
         s.reg3 = regs.slot[3];
-        s.uniform_const = regs.uniform_constant;
+        s.fau_idx = regs.fau_idx;
 
         memcpy(&packed, &s, sizeof(s));
         return packed;
@@ -612,7 +612,7 @@ bi_pack_add_branch_cond(bi_instruction *ins, bi_registers *regs)
         struct bifrost_branch pack = {
                 .src0 = bi_get_src(ins, regs, 0),
                 .src1 = (zero_ctrl << 1) | !slot_swapped,
-                .src2 = BIFROST_SRC_CONST_HI,
+                .src2 = BIFROST_SRC_FAU_HI,
                 .cond = BR_COND_EQ,
                 .size = BR_SIZE_ZERO,
                 .op = BIFROST_ADD_OP_BRANCH
@@ -626,11 +626,11 @@ bi_pack_add_branch_uncond(bi_instruction *ins, bi_registers *regs)
 {
         struct bifrost_branch pack = {
                 /* It's unclear what these bits actually mean */
-                .src0 = BIFROST_SRC_CONST_LO,
+                .src0 = BIFROST_SRC_FAU_LO,
                 .src1 = BIFROST_SRC_PASS_FMA,
 
                 /* Offset, see above */
-                .src2 = BIFROST_SRC_CONST_HI,
+                .src2 = BIFROST_SRC_FAU_HI,
 
                 /* All ones in fact */
                 .cond = (BR_ALWAYS & 0x7),
@@ -894,7 +894,7 @@ static struct bi_packed_bundle
 bi_pack_bundle(bi_clause *clause, bi_bundle bundle, bi_bundle prev, bool first_bundle, gl_shader_stage stage)
 {
         bi_assign_slots(&bundle, &prev);
-        bi_assign_uniform_constant(clause, &bundle.regs, bundle);
+        bi_assign_fau_idx(clause, &bundle.regs, bundle);
         bundle.regs.first_instruction = first_bundle;
 
         bi_flip_slots(&bundle.regs);
diff --git a/src/panfrost/bifrost/bifrost.h b/src/panfrost/bifrost/bifrost.h
index 0592cc0ae0b..55148c8029f 100644
--- a/src/panfrost/bifrost/bifrost.h
+++ b/src/panfrost/bifrost/bifrost.h
@@ -163,8 +163,8 @@ enum bifrost_packed_src {
         BIFROST_SRC_PORT1    = 1,
         BIFROST_SRC_PORT2    = 2,
         BIFROST_SRC_STAGE    = 3,
-        BIFROST_SRC_CONST_LO = 4,
-        BIFROST_SRC_CONST_HI = 5,
+        BIFROST_SRC_FAU_LO   = 4,
+        BIFROST_SRC_FAU_HI   = 5,
         BIFROST_SRC_PASS_FMA = 6,
         BIFROST_SRC_PASS_ADD = 7,
 };
@@ -252,7 +252,7 @@ enum branch_bit_size {
 };
 
 struct bifrost_regs {
-        unsigned uniform_const : 8;
+        unsigned fau_idx : 8;
         unsigned reg3 : 6;
         unsigned reg2 : 6;
         unsigned reg0 : 5;
diff --git a/src/panfrost/bifrost/bifrost_compile.c b/src/panfrost/bifrost/bifrost_compile.c
index 0f466a6cd47..509f9a38134 100644
--- a/src/panfrost/bifrost/bifrost_compile.c
+++ b/src/panfrost/bifrost/bifrost_compile.c
@@ -158,8 +158,8 @@ bi_emit_frag_out(bi_context *ctx, nir_intrinsic_instr *instr)
                         pan_src_index(&instr->src[0]),
                         BIR_INDEX_REGISTER | 60 /* Can this be arbitrary? */,
                         /* Blend descriptor */
-                        BIR_INDEX_PASS | BIFROST_SRC_CONST_LO,
-                        BIR_INDEX_PASS | BIFROST_SRC_CONST_HI,
+                        BIR_INDEX_PASS | BIFROST_SRC_FAU_LO,
+                        BIR_INDEX_PASS | BIFROST_SRC_FAU_HI,
                 },
                 .src_types = {
                         nir_intrinsic_src_type(instr),
@@ -343,7 +343,7 @@ bi_emit_ld_frag_coord(bi_context *ctx, nir_intrinsic_instr *instr)
                         .dest = bi_make_temp(ctx),
                         .src = {
                                 BIR_INDEX_CONSTANT,
-                                BIR_INDEX_PASS | BIFROST_SRC_CONST_LO
+                                BIR_INDEX_PASS | BIFROST_SRC_FAU_LO
                         },
                         .src_types = { nir_type_uint32, nir_type_uint32 },
                         .constant = {
diff --git a/src/panfrost/bifrost/compiler.h b/src/panfrost/bifrost/compiler.h
index 7b58d092945..bfc58ae35f3 100644
--- a/src/panfrost/bifrost/compiler.h
+++ b/src/panfrost/bifrost/compiler.h
@@ -356,8 +356,8 @@ typedef struct {
         /* Configuration for slots 2/3 */
         struct bifrost_reg_ctrl_23 slot23;
 
-        /* Packed uniform/constant */
-        uint8_t uniform_constant;
+        /* Fast-Access-Uniform RAM index */
+        uint8_t fau_idx;
 
         /* Whether writes are actually for the last instruction */
         bool first_instruction;
@@ -369,6 +369,7 @@ typedef struct {
  */
 
 typedef struct {
+        uint8_t fau_idx;
         bi_registers regs;
         bi_instruction *fma;
         bi_instruction *add;
diff --git a/src/panfrost/bifrost/disassemble.c b/src/panfrost/bifrost/disassemble.c
index acea3e037a4..df1874635a2 100644
--- a/src/panfrost/bifrost/disassemble.c
+++ b/src/panfrost/bifrost/disassemble.c
@@ -186,9 +186,9 @@ static void dump_regs(FILE *fp, struct bifrost_regs srcs, bool first)
         else if (ctrl.slot23.slot3 == BIFROST_OP_WRITE_HI)
                 fprintf(fp, "slot 3: r%d (write hi %s) ", srcs.reg3, slot3_fma);
 
-        if (srcs.uniform_const) {
-                if (srcs.uniform_const & 0x80) {
-                        fprintf(fp, "uniform: u%d", (srcs.uniform_const & 0x7f) * 2);
+        if (srcs.fau_idx) {
+                if (srcs.fau_idx & 0x80) {
+                        fprintf(fp, "uniform: u%d", (srcs.fau_idx & 0x7f) * 2);
                 }
         }
 
@@ -291,15 +291,15 @@ const_fau_to_idx(unsigned fau_value)
         return map[fau_value];
 }
 
-static void dump_uniform_const_src(FILE *fp, struct bifrost_regs srcs, struct bi_constants *consts, bool high32)
+static void dump_fau_src(FILE *fp, struct bifrost_regs srcs, struct bi_constants *consts, bool high32)
 {
-        if (srcs.uniform_const & 0x80) {
-                unsigned uniform = (srcs.uniform_const & 0x7f);
+        if (srcs.fau_idx & 0x80) {
+                unsigned uniform = (srcs.fau_idx & 0x7f);
                 fprintf(fp, "u%d.w%d", uniform, high32);
-        } else if (srcs.uniform_const >= 0x20) {
-                unsigned idx = const_fau_to_idx(srcs.uniform_const >> 4);
+        } else if (srcs.fau_idx >= 0x20) {
+                unsigned idx = const_fau_to_idx(srcs.fau_idx >> 4);
                 uint64_t imm = consts->raw[idx];
-                imm |= (srcs.uniform_const & 0xf);
+                imm |= (srcs.fau_idx & 0xf);
                 if (consts->mods[idx] != BI_CONSTMOD_NONE)
                         dump_pc_imm(fp, imm, consts->mods[idx], high32);
                 else if (high32)
@@ -307,7 +307,7 @@ static void dump_uniform_const_src(FILE *fp, struct bifrost_regs srcs, struct bi
                 else
                         dump_const_imm(fp, imm);
         } else {
-                switch (srcs.uniform_const) {
+                switch (srcs.fau_idx) {
                 case 0:
                         fprintf(fp, "#0");
                         break;
@@ -337,10 +337,10 @@ static void dump_uniform_const_src(FILE *fp, struct bifrost_regs srcs, struct bi
                 case 13:
                 case 14:
                 case 15:
-                        fprintf(fp, "blend_descriptor_%u", (unsigned) srcs.uniform_const - 8);
+                        fprintf(fp, "blend_descriptor_%u", (unsigned) srcs.fau_idx - 8);
                         break;
                 default:
-                        fprintf(fp, "XXX - reserved%u", (unsigned) srcs.uniform_const);
+                        fprintf(fp, "XXX - reserved%u", (unsigned) srcs.fau_idx);
                         break;
                 }
 
@@ -371,10 +371,10 @@ dump_src(FILE *fp, unsigned src, struct bifrost_regs srcs, struct bi_constants *
                         fprintf(fp, "t"); // i.e. the output of FMA this cycle
                 break;
         case 4:
-                dump_uniform_const_src(fp, srcs, consts, false);
+                dump_fau_src(fp, srcs, consts, false);
                 break;
         case 5:
-                dump_uniform_const_src(fp, srcs, consts, true);
+                dump_fau_src(fp, srcs, consts, true);
                 break;
         case 6:
                 fprintf(fp, "t0");