src/panfrost/midgard/midgard.h

   1 /* Author(s):
   2  *   Connor Abbott
   3  *   Alyssa Rosenzweig
   4  *
   5  * Copyright (c) 2013 Connor Abbott (connor@abbott.cx)
   6  * Copyright (c) 2018 Alyssa Rosenzweig (alyssa@rosenzweig.io)
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  24  * THE SOFTWARE.
  25  */
  26
  27 #ifndef __midgard_h__
  28 #define __midgard_h__
  29
  30 #include <stdint.h>
  31 #include <stdbool.h>
  32 #include "panfrost-job.h"
  33
  34 #define MIDGARD_DBG_MSGS                0x0001
  35 #define MIDGARD_DBG_SHADERS             0x0002
  36 #define MIDGARD_DBG_SHADERDB            0x0004
  37
  38 extern int midgard_debug;
  39
  40 typedef enum {
  41         midgard_word_type_alu,
  42         midgard_word_type_load_store,
  43         midgard_word_type_texture,
  44         midgard_word_type_unknown
  45 } midgard_word_type;
  46
  47 typedef enum {
  48         midgard_alu_vmul,
  49         midgard_alu_sadd,
  50         midgard_alu_smul,
  51         midgard_alu_vadd,
  52         midgard_alu_lut
  53 } midgard_alu;
  54
  55 enum {
  56         TAG_INVALID = 0x0,
  57         TAG_BREAK = 0x1,
  58         TAG_TEXTURE_4_VTX = 0x2,
  59         TAG_TEXTURE_4 = 0x3,
  60         TAG_TEXTURE_4_BARRIER = 0x4,
  61         TAG_LOAD_STORE_4 = 0x5,
  62         TAG_UNKNOWN_1 = 0x6,
  63         TAG_UNKNOWN_2 = 0x7,
  64         TAG_ALU_4 = 0x8,
  65         TAG_ALU_8 = 0x9,
  66         TAG_ALU_12 = 0xA,
  67         TAG_ALU_16 = 0xB,
  68         TAG_ALU_4_WRITEOUT = 0xC,
  69         TAG_ALU_8_WRITEOUT = 0xD,
  70         TAG_ALU_12_WRITEOUT = 0xE,
  71         TAG_ALU_16_WRITEOUT = 0xF
  72 };
  73
  74 /*
  75  * ALU words
  76  */
  77
  78 typedef enum {
  79         midgard_alu_op_fadd       = 0x10,
  80         midgard_alu_op_fmul       = 0x14,
  81
  82         midgard_alu_op_fmin       = 0x28,
  83         midgard_alu_op_fmax       = 0x2C,
  84
  85         midgard_alu_op_fmov       = 0x30, /* fmov_rte */
  86         midgard_alu_op_fmov_rtz   = 0x31,
  87         midgard_alu_op_fmov_rtn   = 0x32,
  88         midgard_alu_op_fmov_rtp   = 0x33,
  89         midgard_alu_op_froundeven = 0x34,
  90         midgard_alu_op_ftrunc     = 0x35,
  91         midgard_alu_op_ffloor     = 0x36,
  92         midgard_alu_op_fceil      = 0x37,
  93         midgard_alu_op_ffma       = 0x38,
  94         midgard_alu_op_fdot3      = 0x3C,
  95         midgard_alu_op_fdot3r     = 0x3D,
  96         midgard_alu_op_fdot4      = 0x3E,
  97         midgard_alu_op_freduce    = 0x3F,
  98
  99         midgard_alu_op_iadd       = 0x40,
 100         midgard_alu_op_ishladd    = 0x41, /* a + (b<<1) */
 101         midgard_alu_op_isub       = 0x46,
 102         midgard_alu_op_iaddsat    = 0x48,
 103         midgard_alu_op_uaddsat    = 0x49,
 104         midgard_alu_op_isubsat    = 0x4E,
 105         midgard_alu_op_usubsat    = 0x4F,
 106
 107         midgard_alu_op_imul       = 0x58,
 108
 109         midgard_alu_op_imin       = 0x60,
 110         midgard_alu_op_umin       = 0x61,
 111         midgard_alu_op_imax       = 0x62,
 112         midgard_alu_op_umax       = 0x63,
 113         midgard_alu_op_ihadd      = 0x64,
 114         midgard_alu_op_uhadd      = 0x65,
 115         midgard_alu_op_irhadd     = 0x66,
 116         midgard_alu_op_urhadd     = 0x67,
 117         midgard_alu_op_iasr       = 0x68,
 118         midgard_alu_op_ilsr       = 0x69,
 119         midgard_alu_op_ishl       = 0x6E,
 120
 121         midgard_alu_op_iand       = 0x70,
 122         midgard_alu_op_ior        = 0x71,
 123         midgard_alu_op_inand      = 0x72, /* ~(a & b), for inot let a = b */
 124         midgard_alu_op_inor       = 0x73, /* ~(a | b) */
 125         midgard_alu_op_iandnot    = 0x74, /* (a & ~b), used for not/b2f */
 126         midgard_alu_op_iornot     = 0x75, /* (a | ~b) */
 127         midgard_alu_op_ixor       = 0x76,
 128         midgard_alu_op_inxor      = 0x77, /* ~(a & b) */
 129         midgard_alu_op_iclz       = 0x78, /* Number of zeroes on left */
 130         midgard_alu_op_ibitcount8 = 0x7A, /* Counts bits in 8-bit increments */
 131         midgard_alu_op_imov       = 0x7B,
 132         midgard_alu_op_iabsdiff   = 0x7C,
 133         midgard_alu_op_uabsdiff   = 0x7D,
 134         midgard_alu_op_ichoose    = 0x7E, /* vector, component number - dupe for shuffle() */
 135
 136         midgard_alu_op_feq        = 0x80,
 137         midgard_alu_op_fne        = 0x81,
 138         midgard_alu_op_flt        = 0x82,
 139         midgard_alu_op_fle        = 0x83,
 140         midgard_alu_op_fball_eq   = 0x88,
 141         midgard_alu_op_fball_neq  = 0x89,
 142         midgard_alu_op_fball_lt   = 0x8A, /* all(lessThan(.., ..)) */
 143         midgard_alu_op_fball_lte  = 0x8B, /* all(lessThanEqual(.., ..)) */
 144
 145         midgard_alu_op_fbany_eq   = 0x90,
 146         midgard_alu_op_fbany_neq  = 0x91,
 147         midgard_alu_op_fbany_lt   = 0x92, /* any(lessThan(.., ..)) */
 148         midgard_alu_op_fbany_lte  = 0x93, /* any(lessThanEqual(.., ..)) */
 149
 150         midgard_alu_op_f2i_rte    = 0x98,
 151         midgard_alu_op_f2i_rtz    = 0x99,
 152         midgard_alu_op_f2i_rtn    = 0x9A,
 153         midgard_alu_op_f2i_rtp    = 0x9B,
 154         midgard_alu_op_f2u_rte    = 0x9C,
 155         midgard_alu_op_f2u_rtz    = 0x9D,
 156         midgard_alu_op_f2u_rtn    = 0x9E,
 157         midgard_alu_op_f2u_rtp    = 0x9F,
 158
 159         midgard_alu_op_ieq        = 0xA0,
 160         midgard_alu_op_ine        = 0xA1,
 161         midgard_alu_op_ult        = 0xA2,
 162         midgard_alu_op_ule        = 0xA3,
 163         midgard_alu_op_ilt        = 0xA4,
 164         midgard_alu_op_ile        = 0xA5,
 165         midgard_alu_op_iball_eq   = 0xA8,
 166         midgard_alu_op_iball_neq  = 0xA9,
 167         midgard_alu_op_uball_lt   = 0xAA,
 168         midgard_alu_op_uball_lte  = 0xAB,
 169         midgard_alu_op_iball_lt   = 0xAC,
 170         midgard_alu_op_iball_lte  = 0xAD,
 171
 172         midgard_alu_op_ibany_eq   = 0xB0,
 173         midgard_alu_op_ibany_neq  = 0xB1,
 174         midgard_alu_op_ubany_lt   = 0xB2,
 175         midgard_alu_op_ubany_lte  = 0xB3,
 176         midgard_alu_op_ibany_lt   = 0xB4, /* any(lessThan(.., ..)) */
 177         midgard_alu_op_ibany_lte  = 0xB5, /* any(lessThanEqual(.., ..)) */
 178         midgard_alu_op_i2f_rte    = 0xB8,
 179         midgard_alu_op_i2f_rtz    = 0xB9,
 180         midgard_alu_op_i2f_rtn    = 0xBA,
 181         midgard_alu_op_i2f_rtp    = 0xBB,
 182         midgard_alu_op_u2f_rte    = 0xBC,
 183         midgard_alu_op_u2f_rtz    = 0xBD,
 184         midgard_alu_op_u2f_rtn    = 0xBE,
 185         midgard_alu_op_u2f_rtp    = 0xBF,
 186
 187         midgard_alu_op_icsel_v    = 0xC0, /* condition code r31 */
 188         midgard_alu_op_icsel      = 0xC1, /* condition code r31.w */
 189         midgard_alu_op_fcsel_v    = 0xC4,
 190         midgard_alu_op_fcsel      = 0xC5,
 191         midgard_alu_op_fround     = 0xC6,
 192
 193         midgard_alu_op_fatan_pt2  = 0xE8,
 194         midgard_alu_op_fpow_pt1   = 0xEC,
 195         midgard_alu_op_fpown_pt1  = 0xED,
 196         midgard_alu_op_fpowr_pt1  = 0xEE,
 197
 198         midgard_alu_op_frcp       = 0xF0,
 199         midgard_alu_op_frsqrt     = 0xF2,
 200         midgard_alu_op_fsqrt      = 0xF3,
 201         midgard_alu_op_fexp2      = 0xF4,
 202         midgard_alu_op_flog2      = 0xF5,
 203         midgard_alu_op_fsin       = 0xF6,
 204         midgard_alu_op_fcos       = 0xF7,
 205         midgard_alu_op_fatan2_pt1 = 0xF9,
 206 } midgard_alu_op;
 207
 208 typedef enum {
 209         midgard_outmod_none = 0,
 210         midgard_outmod_pos  = 1,
 211         /* 0x2 unknown */
 212         midgard_outmod_sat  = 3
 213 } midgard_outmod_float;
 214
 215 typedef enum {
 216         midgard_outmod_int_saturate = 0,
 217         midgard_outmod_uint_saturate = 1,
 218         midgard_outmod_int_wrap = 2,
 219         midgard_outmod_int_high = 3, /* Overflowed portion */
 220 } midgard_outmod_int;
 221
 222 typedef enum {
 223         midgard_reg_mode_8 = 0,
 224         midgard_reg_mode_16 = 1,
 225         midgard_reg_mode_32 = 2,
 226         midgard_reg_mode_64 = 3
 227 } midgard_reg_mode;
 228
 229 typedef enum {
 230         midgard_dest_override_lower = 0,
 231         midgard_dest_override_upper = 1,
 232         midgard_dest_override_none = 2
 233 } midgard_dest_override;
 234
 235 typedef enum {
 236         midgard_int_sign_extend = 0,
 237         midgard_int_zero_extend = 1,
 238         midgard_int_normal = 2,
 239         midgard_int_shift = 3
 240 } midgard_int_mod;
 241
 242 #define MIDGARD_FLOAT_MOD_ABS (1 << 0)
 243 #define MIDGARD_FLOAT_MOD_NEG (1 << 1)
 244
 245 typedef struct
 246 __attribute__((__packed__))
 247 {
 248         /* Either midgard_int_mod or from midgard_float_mod_*, depending on the
 249          * type of op */
 250         unsigned mod : 2;
 251
 252         /* replicate lower half if dest = half, or low/high half selection if
 253          * dest = full
 254          */
 255         bool rep_low     : 1;
 256         bool rep_high    : 1; /* unused if dest = full */
 257         bool half        : 1; /* only matters if dest = full */
 258         unsigned swizzle : 8;
 259 }
 260 midgard_vector_alu_src;
 261
 262 typedef struct
 263 __attribute__((__packed__))
 264 {
 265         midgard_alu_op op               :  8;
 266         midgard_reg_mode reg_mode   :  2;
 267         unsigned src1 : 13;
 268         unsigned src2 : 13;
 269         midgard_dest_override dest_override : 2;
 270         unsigned outmod               : 2;
 271         unsigned mask                           : 8;
 272 }
 273 midgard_vector_alu;
 274
 275 typedef struct
 276 __attribute__((__packed__))
 277 {
 278         bool abs           : 1;
 279         bool negate        : 1;
 280         bool full          : 1; /* 0 = half, 1 = full */
 281         unsigned component : 3;
 282 }
 283 midgard_scalar_alu_src;
 284
 285 typedef struct
 286 __attribute__((__packed__))
 287 {
 288         midgard_alu_op op         :  8;
 289         unsigned src1             :  6;
 290         unsigned src2             : 11;
 291         unsigned unknown          :  1;
 292         unsigned outmod :  2;
 293         bool output_full          :  1;
 294         unsigned output_component :  3;
 295 }
 296 midgard_scalar_alu;
 297
 298 typedef struct
 299 __attribute__((__packed__))
 300 {
 301         unsigned src1_reg : 5;
 302         unsigned src2_reg : 5;
 303         unsigned out_reg  : 5;
 304         bool src2_imm     : 1;
 305 }
 306 midgard_reg_info;
 307
 308 /* In addition to conditional branches and jumps (unconditional branches),
 309  * Midgard implements a bit of fixed function functionality used in fragment
 310  * shaders via specially crafted branches. These have special branch opcodes,
 311  * which perform a fixed-function operation and/or use the results of a
 312  * fixed-function operation as the branch condition.  */
 313
 314 typedef enum {
 315         /* Regular branches */
 316         midgard_jmp_writeout_op_branch_uncond = 1,
 317         midgard_jmp_writeout_op_branch_cond = 2,
 318
 319         /* In a fragment shader, execute a discard_if instruction, with the
 320          * corresponding condition code. Terminates the shader, so generally
 321          * set the branch target to out of the shader */
 322         midgard_jmp_writeout_op_discard = 4,
 323
 324         /* Branch if the tilebuffer is not yet ready. At the beginning of a
 325          * fragment shader that reads from the tile buffer, for instance via
 326          * ARM_shader_framebuffer_fetch or EXT_pixel_local_storage, this branch
 327          * operation should be used as a loop. An instruction like
 328          * "br.tilebuffer.always -1" does the trick, corresponding to
 329          * "while(!is_tilebuffer_ready) */
 330         midgard_jmp_writeout_op_tilebuffer_pending = 6,
 331
 332         /* In a fragment shader, try to write out the value pushed to r0 to the
 333          * tilebuffer, subject to unknown state in r1.z and r1.w. If this
 334          * succeeds, the shader terminates. If it fails, it branches to the
 335          * specified branch target. Generally, this should be used in a loop to
 336          * itself, acting as "do { write(r0); } while(!write_successful);" */
 337         midgard_jmp_writeout_op_writeout = 7,
 338 } midgard_jmp_writeout_op;
 339
 340 typedef enum {
 341         midgard_condition_write0 = 0,
 342
 343         /* These condition codes denote a conditional branch on FALSE and on
 344          * TRUE respectively */
 345         midgard_condition_false = 1,
 346         midgard_condition_true = 2,
 347
 348         /* This condition code always branches. For a pure branch, the
 349          * unconditional branch coding should be used instead, but for
 350          * fixed-function branch opcodes, this is still useful */
 351         midgard_condition_always = 3,
 352 } midgard_condition;
 353
 354 typedef struct
 355 __attribute__((__packed__))
 356 {
 357         midgard_jmp_writeout_op op : 3; /* == branch_uncond */
 358         unsigned dest_tag : 4; /* tag of branch destination */
 359         unsigned unknown : 2;
 360         int offset : 7;
 361 }
 362 midgard_branch_uncond;
 363
 364 typedef struct
 365 __attribute__((__packed__))
 366 {
 367         midgard_jmp_writeout_op op : 3; /* == branch_cond */
 368         unsigned dest_tag : 4; /* tag of branch destination */
 369         int offset : 7;
 370         midgard_condition cond : 2;
 371 }
 372 midgard_branch_cond;
 373
 374 typedef struct
 375 __attribute__((__packed__))
 376 {
 377         midgard_jmp_writeout_op op : 3; /* == branch_cond */
 378         unsigned dest_tag : 4; /* tag of branch destination */
 379         unsigned unknown : 2;
 380         signed offset : 23;
 381
 382         /* Extended branches permit inputting up to 4 conditions loaded into
 383          * r31 (two in r31.w and two in r31.x). In the most general case, we
 384          * specify a function f(A, B, C, D) mapping 4 1-bit conditions to a
 385          * single 1-bit branch criteria. Note that the domain of f has 2^(2^4)
 386          * elements, each mapping to 1-bit of output, so we can trivially
 387          * construct a Godel numbering of f as a (2^4)=16-bit integer. This
 388          * 16-bit integer serves as a lookup table to compute f, subject to
 389          * some swaps for ordering.
 390          *
 391          * Interesting, the standard 2-bit condition codes are also a LUT with
 392          * the same format (2^1-bit), but it's usually easier to use enums. */
 393
 394         unsigned cond : 16;
 395 }
 396 midgard_branch_extended;
 397
 398 typedef struct
 399 __attribute__((__packed__))
 400 {
 401         midgard_jmp_writeout_op op : 3; /* == writeout */
 402         unsigned unknown : 13;
 403 }
 404 midgard_writeout;
 405
 406 /*
 407  * Load/store words
 408  */
 409
 410 typedef enum {
 411         midgard_op_ld_st_noop   = 0x03,
 412
 413         /* Unpack a colour from a native format to fp16 */
 414         midgard_op_unpack_colour = 0x05,
 415
 416         /* Packs a colour from fp16 to a native format */
 417         midgard_op_pack_colour   = 0x09,
 418
 419         /* Unclear why this is on the L/S unit, but moves fp32 cube map
 420          * coordinates in r27 to its cube map texture coordinate destination
 421          * (e.g r29). */
 422
 423         midgard_op_ld_cubemap_coords = 0x0E,
 424
 425         /* Loads a global/local/group ID, depending on arguments */
 426         midgard_op_ld_compute_id = 0x10,
 427
 428         /* The L/S unit can do perspective division a clock faster than the ALU
 429          * if you're lucky. Put the vec4 in r27, and call with 0x24 as the
 430          * unknown state; the output will be <x/w, y/w, z/w, 1>. Replace w with
 431          * z for the z version */
 432         midgard_op_ldst_perspective_division_z = 0x12,
 433         midgard_op_ldst_perspective_division_w = 0x13,
 434
 435         /* val in r27.y, address embedded, outputs result to argument. Invert val for sub. Let val = +-1 for inc/dec. */
 436         midgard_op_atomic_add = 0x40,
 437         midgard_op_atomic_add64 = 0x41,
 438
 439         midgard_op_atomic_and = 0x44,
 440         midgard_op_atomic_and64 = 0x45,
 441         midgard_op_atomic_or = 0x48,
 442         midgard_op_atomic_or64 = 0x49,
 443         midgard_op_atomic_xor = 0x4C,
 444         midgard_op_atomic_xor64 = 0x4D,
 445
 446         midgard_op_atomic_imin = 0x50,
 447         midgard_op_atomic_imin64 = 0x51,
 448         midgard_op_atomic_umin = 0x54,
 449         midgard_op_atomic_umin64 = 0x55,
 450         midgard_op_atomic_imax = 0x58,
 451         midgard_op_atomic_imax64 = 0x59,
 452         midgard_op_atomic_umax = 0x5C,
 453         midgard_op_atomic_umax64 = 0x5D,
 454
 455         midgard_op_atomic_xchg = 0x60,
 456         midgard_op_atomic_xchg64 = 0x61,
 457
 458         /* Used for compute shader's __global arguments, __local variables (or
 459          * for register spilling) */
 460
 461         midgard_op_ld_char = 0x81,
 462         midgard_op_ld_char2 = 0x84,
 463         midgard_op_ld_short = 0x85,
 464         midgard_op_ld_char4 = 0x88, /* short2, int, float */
 465         midgard_op_ld_short4 = 0x8C, /* int2, float2, long */
 466         midgard_op_ld_int4 = 0x90, /* float4, long2 */
 467
 468         midgard_op_ld_attr_32 = 0x94,
 469         midgard_op_ld_attr_16 = 0x95,
 470         midgard_op_ld_attr_32u = 0x96,
 471         midgard_op_ld_attr_32i = 0x97,
 472         midgard_op_ld_vary_32 = 0x98,
 473         midgard_op_ld_vary_16 = 0x99,
 474         midgard_op_ld_vary_32u = 0x9A,
 475         midgard_op_ld_vary_32i = 0x9B,
 476
 477         /* Old version of midgard_op_ld_color_buffer_u8_as_fp16, for T720 */
 478         midgard_op_ld_color_buffer_u8_as_fp16_old = 0x9D,
 479
 480         /* The distinction between these ops is the alignment requirement /
 481          * accompanying shift. Thus, the offset to ld_ubo_int4 is in 16-byte
 482          * units and can load 128-bit. The offset to ld_ubo_short4 is in 8-byte
 483          * units; ld_ubo_char4 in 4-byte units. ld_ubo_char/ld_ubo_char2 are
 484          * purely theoretical (never seen in the wild) since int8/int16/fp16
 485          * UBOs don't really exist. The ops are still listed to maintain
 486          * symmetry with generic I/O ops. */
 487
 488         midgard_op_ld_ubo_char   = 0xA0, /* theoretical */
 489         midgard_op_ld_ubo_char2  = 0xA4, /* theoretical */
 490         midgard_op_ld_ubo_char4  = 0xA8,
 491         midgard_op_ld_ubo_short4 = 0xAC,
 492         midgard_op_ld_ubo_int4   = 0xB0,
 493
 494         /* New-style blending ops. Works on T760/T860 */
 495         midgard_op_ld_color_buffer_u8_as_fp16 = 0xB9,
 496         midgard_op_ld_color_buffer_32u = 0xBA,
 497
 498         midgard_op_st_char = 0xC0,
 499         midgard_op_st_char2 = 0xC4, /* short */
 500         midgard_op_st_char4 = 0xC8, /* short2, int, float */
 501         midgard_op_st_short4 = 0xCC, /* int2, float2, long */
 502         midgard_op_st_int4 = 0xD0, /* float4, long2 */
 503
 504         midgard_op_st_vary_32 = 0xD4,
 505         midgard_op_st_vary_16 = 0xD5,
 506         midgard_op_st_vary_32u = 0xD6,
 507         midgard_op_st_vary_32i = 0xD7,
 508
 509         /* Value to st in r27, location r26.w as short2 */
 510         midgard_op_st_image_f = 0xD8,
 511         midgard_op_st_image_ui = 0xDA,
 512         midgard_op_st_image_i = 0xDB,
 513 } midgard_load_store_op;
 514
 515 typedef enum {
 516         midgard_interp_centroid = 1,
 517         midgard_interp_default = 2
 518 } midgard_interpolation;
 519
 520 typedef enum {
 521         midgard_varying_mod_none = 0,
 522
 523         /* Other values unknown */
 524
 525         /* Take the would-be result and divide all components by its z/w
 526          * (perspective division baked in with the load)  */
 527         midgard_varying_mod_perspective_z = 2,
 528         midgard_varying_mod_perspective_w = 3,
 529 } midgard_varying_modifier;
 530
 531 typedef struct
 532 __attribute__((__packed__))
 533 {
 534         unsigned zero0 : 1; /* Always zero */
 535
 536         midgard_varying_modifier modifier : 2;
 537
 538         unsigned zero1: 1; /* Always zero */
 539
 540         /* Varying qualifiers, zero if not a varying */
 541         unsigned flat    : 1;
 542         unsigned is_varying : 1; /* Always one for varying, but maybe something else? */
 543         midgard_interpolation interpolation : 2;
 544
 545         unsigned zero2 : 2; /* Always zero */
 546 }
 547 midgard_varying_parameter;
 548
 549 /* 8-bit register/etc selector for load/store ops */
 550 typedef struct
 551 __attribute__((__packed__))
 552 {
 553         /* Indexes into the register */
 554         unsigned component : 2;
 555
 556         /* Register select between r26/r27 */
 557         unsigned select : 1;
 558
 559         unsigned unknown : 2;
 560
 561         /* Like any good Arm instruction set, load/store arguments can be
 562          * implicitly left-shifted... but only the second argument. Zero for no
 563          * shifting, up to <<7 possible though. This is useful for indexing.
 564          *
 565          * For the first argument, it's unknown what these bits mean */
 566         unsigned shift : 3;
 567 }
 568 midgard_ldst_register_select;
 569
 570 typedef struct
 571 __attribute__((__packed__))
 572 {
 573         midgard_load_store_op op : 8;
 574         unsigned reg     : 5;
 575         unsigned mask    : 4;
 576         unsigned swizzle : 8;
 577
 578         /* Load/store ops can take two additional registers as arguments, but
 579          * these are limited to load/store registers with only a few supported
 580          * mask/swizzle combinations. The tradeoff is these are much more
 581          * compact, requiring 8-bits each rather than 17-bits for a full
 582          * reg/mask/swizzle. Usually (?) encoded as
 583          * midgard_ldst_register_select. */
 584         unsigned arg_1   : 8;
 585         unsigned arg_2   : 8;
 586
 587         unsigned varying_parameters : 10;
 588
 589         unsigned address : 9;
 590 }
 591 midgard_load_store_word;
 592
 593 typedef struct
 594 __attribute__((__packed__))
 595 {
 596         unsigned type      : 4;
 597         unsigned next_type : 4;
 598         uint64_t word1     : 60;
 599         uint64_t word2     : 60;
 600 }
 601 midgard_load_store;
 602
 603 /* 8-bit register selector used in texture ops to select a bias/LOD/gradient
 604  * register, shoved into the `bias` field */
 605
 606 typedef struct
 607 __attribute__((__packed__))
 608 {
 609         /* 32-bit register, clear for half-register */
 610         unsigned full : 1;
 611
 612         /* Register select between r28/r29 */
 613         unsigned select : 1;
 614
 615         /* For a half-register, selects the upper half */
 616         unsigned upper : 1;
 617
 618         /* Indexes into the register */
 619         unsigned component : 2;
 620
 621         /* Padding to make this 8-bit */
 622         unsigned zero : 3;
 623 }
 624 midgard_tex_register_select;
 625
 626 /* Texture pipeline results are in r28-r29 */
 627 #define REG_TEX_BASE 28
 628
 629 /* Texture opcodes... maybe? */
 630 #define TEXTURE_OP_NORMAL 0x11          /* texture */
 631 #define TEXTURE_OP_LOD 0x12             /* textureLod */
 632 #define TEXTURE_OP_TEXEL_FETCH 0x14     /* texelFetch */
 633
 634 /* Implements barrier() */
 635 #define TEXTURE_OP_BARRIER 0x0B
 636
 637 /* Computes horizontal and vertical derivatives respectively. Use with a float
 638  * sampler and a "2D" texture.  Leave texture/sampler IDs as zero; they ought
 639  * to be ignored. Only works for fp32 on 64-bit at a time, so derivatives of a
 640  * vec4 require 2 texture ops.  For some reason, the blob computes both X and Y
 641  * derivatives at the same time and just throws out whichever is unused; it's
 642  * not known if this is a quirk of the hardware or just of the blob. */
 643
 644 #define TEXTURE_OP_DFDX 0x0D
 645 #define TEXTURE_OP_DFDY 0x1D
 646
 647 enum mali_sampler_type {
 648         MALI_SAMPLER_UNK        = 0x0,
 649         MALI_SAMPLER_FLOAT      = 0x1, /* sampler */
 650         MALI_SAMPLER_UNSIGNED   = 0x2, /* usampler */
 651         MALI_SAMPLER_SIGNED     = 0x3, /* isampler */
 652 };
 653
 654 typedef struct
 655 __attribute__((__packed__))
 656 {
 657         unsigned type      : 4;
 658         unsigned next_type : 4;
 659
 660         unsigned op  : 6;
 661         unsigned shadow    : 1;
 662         unsigned is_gather  : 1;
 663
 664         /* A little obscure, but last is set for the last texture operation in
 665          * a shader. cont appears to just be last's opposite (?). Yeah, I know,
 666          * kind of funky.. BiOpen thinks it could do with memory hinting, or
 667          * tile locking? */
 668
 669         unsigned cont  : 1;
 670         unsigned last  : 1;
 671
 672         enum mali_texture_type format : 2;
 673
 674         /* Are sampler_handle/texture_handler respectively set by registers? If
 675          * true, the lower 8-bits of the respective field is a register word.
 676          * If false, they are an immediate */
 677
 678         unsigned sampler_register : 1;
 679         unsigned texture_register : 1;
 680
 681         /* Is a register used to specify the
 682          * LOD/bias/offset? If set, use the `bias` field as
 683          * a register index. If clear, use the `bias` field
 684          * as an immediate. */
 685         unsigned lod_register : 1;
 686
 687         /* Is a register used to specify an offset? If set, use the
 688          * offset_reg_* fields to encode this, duplicated for each of the
 689          * components. If clear, there is implcitly always an immediate offst
 690          * specificed in offset_imm_* */
 691         unsigned offset_register : 1;
 692
 693         unsigned in_reg_full  : 1;
 694         unsigned in_reg_select : 1;
 695         unsigned in_reg_upper  : 1;
 696         unsigned in_reg_swizzle : 8;
 697
 698         unsigned unknown8  : 2;
 699
 700         unsigned out_full  : 1;
 701
 702         enum mali_sampler_type sampler_type : 2;
 703
 704         unsigned out_reg_select : 1;
 705         unsigned out_upper : 1;
 706
 707         unsigned mask : 4;
 708
 709         /* Intriguingly, textures can take an outmod just like textures. Int
 710          * outmods are not supported as far as I can tell, so this is only
 711          * meaningful for float samplers */
 712         midgard_outmod_float outmod  : 2;
 713
 714         unsigned swizzle  : 8;
 715
 716         /* For barriers, control barriers are implied regardless, but these
 717          * bits also enable memory barriers of various types. For regular
 718          * textures, these bits are not yet understood. */
 719         unsigned barrier_buffer : 1;
 720         unsigned barrier_shared : 1;
 721         unsigned barrier_stack  : 1;
 722
 723         unsigned unknown4  : 9;
 724
 725         /* In immediate mode, each offset field is an immediate range [0, 7].
 726          *
 727          * In register mode, offset_x becomes a register full / select / upper
 728          * triplet followed by a vec3 swizzle is splattered across
 729          * offset_y/offset_z in a genuinely bizarre way.
 730          *
 731          * For texel fetches in immediate mode, the range is the full [-8, 7],
 732          * but for normal texturing the top bit must be zero and a register
 733          * used instead. It's not clear where this limitation is from.
 734          *
 735          * union {
 736          *      struct {
 737          *              signed offset_x  : 4;
 738          *              signed offset_y  : 4;
 739          *              signed offset_z  : 4;
 740          *      } immediate;
 741          *      struct {
 742          *              bool full        : 1;
 743          *              bool select      : 1;
 744          *              bool upper       : 1;
 745          *              unsigned swizzle : 8;
 746          *              unsigned zero    : 1;
 747          *      } register;
 748          * }
 749          */
 750
 751         unsigned offset : 12;
 752
 753         /* In immediate bias mode, for a normal texture op, this is
 754          * texture bias, computed as int(2^8 * frac(biasf)), with
 755          * bias_int = floor(bias). For a textureLod, it's that, but
 756          * s/bias/lod. For a texel fetch, this is the LOD as-is.
 757          *
 758          * In register mode, this is a midgard_tex_register_select
 759          * structure and bias_int is zero */
 760
 761         unsigned bias : 8;
 762         signed bias_int  : 8;
 763
 764         /* If sampler/texture_register is set, the bottom 8-bits are
 765          * midgard_tex_register_select and the top 8-bits are zero. If they are
 766          * clear, they are immediate texture indices */
 767
 768         unsigned sampler_handle : 16;
 769         unsigned texture_handle : 16;
 770 }
 771 midgard_texture_word;
 772
 773 /* Technically barriers are texture instructions but it's less work to add them
 774  * as an explicitly zeroed special case, since most fields are forced to go to
 775  * zero */
 776
 777 typedef struct
 778 __attribute__((__packed__))
 779 {
 780         unsigned type      : 4;
 781         unsigned next_type : 4;
 782
 783         /* op = TEXTURE_OP_BARRIER */
 784         unsigned op  : 6;
 785         unsigned zero1    : 2;
 786
 787         /* Since helper invocations don't make any sense, these are forced to one */
 788         unsigned cont  : 1;
 789         unsigned last  : 1;
 790         unsigned zero2 : 14;
 791
 792         unsigned zero3 : 24;
 793         unsigned buffer : 1;
 794         unsigned shared : 1;
 795         unsigned stack  : 1;
 796         unsigned zero4 : 5;
 797
 798         uint64_t zero5;
 799 } midgard_texture_barrier_word;
 800
 801 typedef union midgard_constants {
 802         double f64[2];
 803         uint64_t u64[2];
 804         int64_t i64[2];
 805         float f32[4];
 806         uint32_t u32[4];
 807         int32_t i32[4];
 808         uint16_t f16[8];
 809         uint16_t u16[8];
 810         int16_t i16[8];
 811         uint8_t u8[16];
 812         int8_t i8[16];
 813 }
 814 midgard_constants;
 815
 816 #endif