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_ADDPCIS, 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,
  11                          OP_EXTSWSLI, OP_ICBI, OP_ICBT, OP_ISEL, OP_ISYNC,
  12                          OP_LOAD, OP_STORE, OP_MADDHD, OP_MADDHDU, OP_MADDLD,
  13                          OP_MCRXR, OP_MCRXRX, OP_MFCR, OP_MFMSR, OP_MFSPR, OP_MOD,
  14                          OP_MTCRF, OP_MTMSRD, OP_MTSPR, OP_MUL_L64,
  15                          OP_MUL_H64, OP_MUL_H32, OP_OR,
  16                          OP_POPCNT, OP_PRTY, OP_RFID,
  17                          OP_RLC, OP_RLCL, OP_RLCR, OP_SC, OP_SETB,
  18                          OP_SHL, OP_SHR,
  19                          OP_SYNC, OP_TRAP,
  20                          OP_XOR
  21                          );
  22     type input_reg_a_t is (NONE, RA, RA_OR_ZERO, SPR);
  23     type input_reg_b_t is (NONE, RB, CONST_UI, CONST_SI, CONST_SI_HI, CONST_UI_HI, CONST_LI, CONST_BD, CONST_DS, CONST_M1, CONST_SH, CONST_SH32, SPR);
  24     type input_reg_c_t is (NONE, RS);
  25     type output_reg_a_t is (NONE, RT, RA, SPR);
  26     type rc_t is (NONE, ONE, RC);
  27     type carry_in_t is (ZERO, CA, ONE);
  28
  29     constant SH_OFFSET : integer := 0;
  30     constant MB_OFFSET : integer := 1;
  31     constant ME_OFFSET : integer := 1;
  32     constant SH32_OFFSET : integer := 0;
  33     constant MB32_OFFSET : integer := 1;
  34     constant ME32_OFFSET : integer := 2;
  35
  36     constant FXM_OFFSET : integer := 0;
  37
  38     constant BO_OFFSET : integer := 0;
  39     constant BI_OFFSET : integer := 1;
  40     constant BH_OFFSET : integer := 2;
  41
  42     constant BF_OFFSET : integer := 0;
  43     constant L_OFFSET  : integer := 1;
  44
  45     constant TOO_OFFSET : integer := 0;
  46
  47     type unit_t is (NONE, ALU, LDST);
  48     type length_t is (NONE, is1B, is2B, is4B, is8B);
  49
  50     type decode_rom_t is record
  51         unit         : unit_t;
  52         insn_type    : insn_type_t;
  53         input_reg_a  : input_reg_a_t;
  54         input_reg_b  : input_reg_b_t;
  55         input_reg_c  : input_reg_c_t;
  56         output_reg_a : output_reg_a_t;
  57
  58         input_cr     : std_ulogic;
  59         output_cr    : std_ulogic;
  60
  61         invert_a     : std_ulogic;
  62         invert_out   : std_ulogic;
  63         input_carry  : carry_in_t;
  64         output_carry : std_ulogic;
  65
  66         -- load/store signals
  67         length       : length_t;
  68         byte_reverse : std_ulogic;
  69         sign_extend  : std_ulogic;
  70         update       : std_ulogic;
  71         reserve      : std_ulogic;
  72
  73         -- multiplier and ALU signals
  74         is_32bit     : std_ulogic;
  75         is_signed    : std_ulogic;
  76
  77         rc           : rc_t;
  78         lr           : std_ulogic;
  79
  80         sgl_pipe     : std_ulogic;
  81     end record;
  82     constant decode_rom_init : decode_rom_t := (unit => NONE,
  83                                                 insn_type => OP_ILLEGAL, input_reg_a => NONE,
  84                                                 input_reg_b => NONE, input_reg_c => NONE,
  85                                                 output_reg_a => NONE, input_cr => '0', output_cr => '0',
  86                                                 invert_a => '0', invert_out => '0', input_carry => ZERO, output_carry => '0',
  87                                                 length => NONE, byte_reverse => '0', sign_extend => '0',
  88                                                 update => '0', reserve => '0', is_32bit => '0',
  89                                                 is_signed => '0', rc => NONE, lr => '0', sgl_pipe => '0');
  90
  91 end decode_types;
  92
  93 package body decode_types is
  94 end decode_types;