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_FPLOAD, OP_FPSTORE,
  15                          OP_MCRXRX, OP_MFCR, OP_MFMSR, OP_MFSPR, OP_MOD,
  16                          OP_MTCRF, OP_MTMSRD, OP_MTSPR, OP_MUL_L64,
  17                          OP_MUL_H64, OP_MUL_H32, OP_OR,
  18                          OP_POPCNT, OP_PRTY, OP_RFID,
  19                          OP_RLC, OP_RLCL, OP_RLCR, OP_SC, OP_SETB,
  20                          OP_SHL, OP_SHR,
  21                          OP_SYNC, OP_TLBIE, OP_TRAP,
  22                          OP_XOR,
  23                          OP_BCD, OP_ADDG6S,
  24                          OP_FETCH_FAILED
  25                          );
  26     type input_reg_a_t is (NONE, RA, RA_OR_ZERO, SPR, CIA, FRA);
  27     type input_reg_b_t is (NONE, RB, CONST_UI, CONST_SI, CONST_SI_HI, CONST_UI_HI, CONST_LI, CONST_BD,
  28                            CONST_DXHI4, CONST_DS, CONST_M1, CONST_SH, CONST_SH32, SPR, FRB);
  29     type input_reg_c_t is (NONE, RS, RCR, FRC, FRS);
  30     type output_reg_a_t is (NONE, RT, RA, SPR, FRT);
  31     type rc_t is (NONE, ONE, RC);
  32     type carry_in_t is (ZERO, CA, OV, ONE);
  33
  34     constant SH_OFFSET : integer := 0;
  35     constant MB_OFFSET : integer := 1;
  36     constant ME_OFFSET : integer := 1;
  37     constant SH32_OFFSET : integer := 0;
  38     constant MB32_OFFSET : integer := 1;
  39     constant ME32_OFFSET : integer := 2;
  40
  41     constant FXM_OFFSET : integer := 0;
  42
  43     constant BO_OFFSET : integer := 0;
  44     constant BI_OFFSET : integer := 1;
  45     constant BH_OFFSET : integer := 2;
  46
  47     constant BF_OFFSET : integer := 0;
  48     constant L_OFFSET  : integer := 1;
  49
  50     constant TOO_OFFSET : integer := 0;
  51
  52     type unit_t is (NONE, ALU, LDST, FPU);
  53     type length_t is (NONE, is1B, is2B, is4B, is8B);
  54
  55     type decode_rom_t is record
  56         unit         : unit_t;
  57         insn_type    : insn_type_t;
  58         input_reg_a  : input_reg_a_t;
  59         input_reg_b  : input_reg_b_t;
  60         input_reg_c  : input_reg_c_t;
  61         output_reg_a : output_reg_a_t;
  62
  63         input_cr     : std_ulogic;
  64         output_cr    : std_ulogic;
  65
  66         invert_a     : std_ulogic;
  67         invert_out   : std_ulogic;
  68         input_carry  : carry_in_t;
  69         output_carry : std_ulogic;
  70
  71         -- load/store signals
  72         length       : length_t;
  73         byte_reverse : std_ulogic;
  74         sign_extend  : std_ulogic;
  75         update       : std_ulogic;
  76         reserve      : std_ulogic;
  77
  78         -- multiplier and ALU signals
  79         is_32bit     : std_ulogic;
  80         is_signed    : std_ulogic;
  81
  82         rc           : rc_t;
  83         lr           : std_ulogic;
  84
  85         sgl_pipe     : std_ulogic;
  86     end record;
  87     constant decode_rom_init : decode_rom_t := (unit => NONE,
  88                                                 insn_type => OP_ILLEGAL, input_reg_a => NONE,
  89                                                 input_reg_b => NONE, input_reg_c => NONE,
  90                                                 output_reg_a => NONE, input_cr => '0', output_cr => '0',
  91                                                 invert_a => '0', invert_out => '0', input_carry => ZERO, output_carry => '0',
  92                                                 length => NONE, byte_reverse => '0', sign_extend => '0',
  93                                                 update => '0', reserve => '0', is_32bit => '0',
  94                                                 is_signed => '0', rc => NONE, lr => '0', sgl_pipe => '0');
  95
  96 end decode_types;
  97
  98 package body decode_types is
  99 end decode_types;