decode_types.vhdl

   1 library ieee;
   2 use ieee.std_logic_1164.all;
   3
   4 package decode_types is
   5     type insn_type_t is (OP_ILLEGAL, OP_NOP, OP_ADD,
   6                          OP_AND, OP_ATTN, OP_B, OP_BC, OP_BCREG,
   7                          OP_BPERM, OP_CMP, OP_CMPB, OP_CMPEQB, OP_CMPRB,
   8                          OP_CNTZ, OP_CROP,
   9                          OP_DARN, OP_DCBF, OP_DCBST, OP_DCBT, OP_DCBTST,
  10                          OP_DCBZ, OP_DIV, OP_DIVE, OP_EXTS, OP_EXTSWSLI,
  11                          OP_FPOP, OP_FPOP_I,
  12                          OP_ICBI, OP_ICBT, OP_ISEL, OP_ISYNC,
  13                          OP_LOAD, OP_STORE,
  14                          OP_MCRXRX, OP_MFCR, OP_MFMSR, OP_MFSPR, OP_MOD,
  15                          OP_MTCRF, OP_MTMSRD, OP_MTSPR, OP_MUL_L64,
  16                          OP_MUL_H64, OP_MUL_H32, OP_OR,
  17                          OP_POPCNT, OP_PRTY, OP_RFID,
  18                          OP_RLC, OP_RLCL, OP_RLCR, OP_SC, OP_SETB,
  19                          OP_SHL, OP_SHR,
  20                          OP_SYNC, OP_TLBIE, OP_TRAP,
  21                          OP_XOR,
  22                          OP_BCD, OP_ADDG6S,
  23                          OP_FETCH_FAILED
  24                          );
  25     type input_reg_a_t is (NONE, RA, RA_OR_ZERO, SPR, CIA, FRA);
  26     type input_reg_b_t is (NONE, RB, CONST_UI, CONST_SI, CONST_SI_HI, CONST_UI_HI, CONST_LI, CONST_BD,
  27                            CONST_DXHI4, CONST_DS, CONST_DQ, CONST_M1, CONST_SH, CONST_SH32, SPR, FRB);
  28     type input_reg_c_t is (NONE, RS, RCR, FRC, FRS);
  29     type output_reg_a_t is (NONE, RT, RA, SPR, FRT);
  30     type rc_t is (NONE, ONE, RC);
  31     type carry_in_t is (ZERO, CA, OV, ONE);
  32
  33     constant SH_OFFSET : integer := 0;
  34     constant MB_OFFSET : integer := 1;
  35     constant ME_OFFSET : integer := 1;
  36     constant SH32_OFFSET : integer := 0;
  37     constant MB32_OFFSET : integer := 1;
  38     constant ME32_OFFSET : integer := 2;
  39
  40     constant FXM_OFFSET : integer := 0;
  41
  42     constant BO_OFFSET : integer := 0;
  43     constant BI_OFFSET : integer := 1;
  44     constant BH_OFFSET : integer := 2;
  45
  46     constant BF_OFFSET : integer := 0;
  47     constant L_OFFSET  : integer := 1;
  48
  49     constant TOO_OFFSET : integer := 0;
  50
  51     type unit_t is (NONE, ALU, LDST, FPU);
  52     type facility_t is (NONE, FPU);
  53     type length_t is (NONE, is1B, is2B, is4B, is8B);
  54
  55     type repeat_t is (NONE,      -- instruction is not repeated
  56                       DRSE,      -- double RS, endian twist
  57                       DRTE);     -- double RT, endian twist
  58
  59     type decode_rom_t is record
  60         unit         : unit_t;
  61         facility     : facility_t;
  62         insn_type    : insn_type_t;
  63         input_reg_a  : input_reg_a_t;
  64         input_reg_b  : input_reg_b_t;
  65         input_reg_c  : input_reg_c_t;
  66         output_reg_a : output_reg_a_t;
  67
  68         input_cr     : std_ulogic;
  69         output_cr    : std_ulogic;
  70
  71         invert_a     : std_ulogic;
  72         invert_out   : std_ulogic;
  73         input_carry  : carry_in_t;
  74         output_carry : std_ulogic;
  75
  76         -- load/store signals
  77         length       : length_t;
  78         byte_reverse : std_ulogic;
  79         sign_extend  : std_ulogic;
  80         update       : std_ulogic;
  81         reserve      : std_ulogic;
  82
  83         -- multiplier and ALU signals
  84         is_32bit     : std_ulogic;
  85         is_signed    : std_ulogic;
  86
  87         rc           : rc_t;
  88         lr           : std_ulogic;
  89
  90         sgl_pipe     : std_ulogic;
  91         repeat       : repeat_t;
  92     end record;
  93     constant decode_rom_init : decode_rom_t := (unit => NONE, facility => NONE,
  94                                                 insn_type => OP_ILLEGAL, input_reg_a => NONE,
  95                                                 input_reg_b => NONE, input_reg_c => NONE,
  96                                                 output_reg_a => NONE, input_cr => '0', output_cr => '0',
  97                                                 invert_a => '0', invert_out => '0', input_carry => ZERO, output_carry => '0',
  98                                                 length => NONE, byte_reverse => '0', sign_extend => '0',
  99                                                 update => '0', reserve => '0', is_32bit => '0',
 100                                                 is_signed => '0', rc => NONE, lr => '0', sgl_pipe => '0', repeat => NONE);
 101
 102 end decode_types;
 103
 104 package body decode_types is
 105 end decode_types;