//======================================================================
//
// Copyright: 2019, The Commons Conservancy Cryptech Project
// SPDX-License-Identifier: BSD-3-Clause
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// - Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
//
// - Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.
//
// - Neither the name of the copyright holder nor the names of its
//   contributors may be used to endorse or promote products derived from
//   this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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//
//======================================================================

//
// Headers
//
`include "modexpng_parameters_x8.vh"
`include "cryptech_clog2.vh"

//
// Debug Settings
//

/* Only define this for simulation, must be turned off to synthesize properly! */
//`define MODEXPNG_ENABLE_DEBUG

//
// Core Settings
//
localparam MAX_OP_W      = 4096;
localparam WORD_W        = 16;
localparam WORD_EXT_W    = 18;
localparam MAC_W         = 47;
localparam BUS_DATA_W    = 32;
localparam BUS_OP_ADDR_W = cryptech_clog2(MAX_OP_W / BUS_DATA_W);
localparam BIT_INDEX_W   = cryptech_clog2(MAX_OP_W);
localparam BANK_ADDR_W   = 3;
localparam OP_ADDR_W     = cryptech_clog2(MAX_OP_W / WORD_W); 
localparam MAC_INDEX_W   = cryptech_clog2(NUM_MULTS);
localparam COL_INDEX_W   = OP_ADDR_W - MAC_INDEX_W; 
localparam CARRY_W       = WORD_EXT_W - WORD_W;
localparam WORD_MUX_W    = cryptech_clog2(WORD_W);

//
// Wide Bank
//
localparam [BANK_ADDR_W-1:0] BANK_WIDE_A = 3'd0;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_B = 3'd1;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_C = 3'd2;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_D = 3'd3;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_E = 3'd4;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_N = 3'd5;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_L = 3'd6;
localparam [BANK_ADDR_W-1:0] BANK_WIDE_H = 3'd7;

//
// Narrow Bank
//
localparam [BANK_ADDR_W-1:0] BANK_NARROW_A     = 3'd0;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_B     = 3'd1;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_C     = 3'd2;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_D     = 3'd3;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_E     = 3'd4;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_COEFF = 3'd5;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_Q     = 3'd6;
localparam [BANK_ADDR_W-1:0] BANK_NARROW_EXT   = 3'd7; // [0] -> COEFF', [1] -> Q'

//
// Recombinator Bank
//
localparam [BANK_ADDR_W-1:0] BANK_RCMB_ML  = 3'd0;
localparam [BANK_ADDR_W-1:0] BANK_RCMB_MH  = 3'd1;
localparam [BANK_ADDR_W-1:0] BANK_RCMB_EXT = 3'd2; // [0] -> MH'

//
// Input Bank #1
//
localparam [BANK_ADDR_W-1:0] BANK_IN_1_M        = 3'd0;
localparam [BANK_ADDR_W-1:0] BANK_IN_1_N        = 3'd1;
localparam [BANK_ADDR_W-1:0] BANK_IN_1_N_FACTOR = 3'd2;
localparam [BANK_ADDR_W-1:0] BANK_IN_1_N_COEFF  = 3'd3;/*
localparam [BANK_ADDR_W-1:0] BANK_IN_1_EXT      = 3'd4; // [0] -> N_COEFF'*/
localparam [BANK_ADDR_W-1:0] BANK_IN_1_X        = 3'd5;
localparam [BANK_ADDR_W-1:0] BANK_IN_1_Y        = 3'd6;

//
// Input Bank #2
//
localparam [BANK_ADDR_W-1:0] BANK_IN_2_D        = 3'd0;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_P        = 3'd1;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_P_FACTOR = 3'd2;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_P_COEFF  = 3'd3;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_Q        = 3'd4;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_Q_FACTOR = 3'd5;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_Q_COEFF  = 3'd6;
localparam [BANK_ADDR_W-1:0] BANK_IN_2_QINV     = 3'd7;

//
// Output Bank
//
localparam [BANK_ADDR_W-1:0] BANK_OUT_S  = 3'd0;
localparam [BANK_ADDR_W-1:0] BANK_OUT_XM = 3'd1;
localparam [BANK_ADDR_W-1:0] BANK_OUT_YM = 3'd2;

//
// Carry Values
//
localparam [CARRY_W-1:0] CARRY_ZERO = {CARRY_W{1'b0}};

//
// Bank Values
//
localparam [  BANK_ADDR_W-1:0] BANK_DNC     = {BANK_ADDR_W{1'bX}};
localparam [4*BANK_ADDR_W-1:0] BANK_DNC_ALL = {4{BANK_DNC}};

//
// Operand Address Values
//
localparam [OP_ADDR_W-1:0] OP_ADDR_LADDER_LAST = 3; // 0..3, i.e. <dummy>, D, P, Q
localparam [OP_ADDR_W-1:0] OP_ADDR_EXT_COEFF   = 0;
localparam [OP_ADDR_W-1:0] OP_ADDR_EXT_Q       = 1;
localparam [OP_ADDR_W-1:0] OP_ADDR_ZERO        = {OP_ADDR_W{1'b0}};
localparam [OP_ADDR_W-1:0] OP_ADDR_ONE         = {{(OP_ADDR_W-1){1'b0}}, 1'b1};
localparam [OP_ADDR_W-1:0] OP_ADDR_TWO         = {OP_ADDR_ONE[OP_ADDR_W-2:0], 1'b0};
localparam [OP_ADDR_W-1:0] OP_ADDR_DNC         = {OP_ADDR_W{1'bX}};

//
// Bit Index Values
//
localparam [BIT_INDEX_W-1:0] BIT_INDEX_ZERO = {BIT_INDEX_W{1'b0}};
localparam [BIT_INDEX_W-1:0] BIT_INDEX_DNC  = {BIT_INDEX_W{1'bX}};

//
// Word Values
//
localparam [WORD_W-1:0] WORD_ZERO = {WORD_W{1'b0}};
localparam [WORD_W-1:0] WORD_DNC  = {WORD_W{1'bX}};
localparam [WORD_W-1:0] WORD_ONE  = {{(WORD_W-1){1'b0}}, 1'b1};

//
// Extended Word Values
//
localparam [WORD_EXT_W-1:0] WORD_EXT_ZERO = {WORD_EXT_W{1'b0}};
localparam [WORD_EXT_W-1:0] WORD_EXT_DNC  = {WORD_EXT_W{1'bX}};

//
// MAC Index Values
//
localparam [MAC_INDEX_W-1:0] MAC_INDEX_DNC = {MAC_INDEX_W{1'bX}};

//
// Multiplier Bitmap Values
//
localparam [NUM_MULTS-1:0] MULT_BITMAP_ZEROES = {NUM_MULTS{1'b0}};


//
// Column Index Values
//
localparam [COL_INDEX_W-1:0] COL_INDEX_ZERO = {COL_INDEX_W{1'b0}};
localparam [COL_INDEX_W-1:0] COL_INDEX_ONE  = {{(COL_INDEX_W-1){1'b0}}, 1'b1};