// © IBM Corp. 2020
// Licensed under the Apache License, Version 2.0 (the "License"), as modified by
// the terms below; you may not use the files in this repository except in
// compliance with the License as modified.
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//
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//
//    1) For the purpose of the patent license granted to you in Section 3 of the
//    License, the "Work" hereby includes implementations of the work of authorship
//    in physical form.
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//    necessary for implementation of the Work that are available from OpenPOWER
//    via the Power ISA End User License Agreement (EULA) are explicitly excluded
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`timescale 1 ns / 1 ns

// *!****************************************************************
// *! FILENAME    : tri_rlmreg_p.v
// *! DESCRIPTION : Multi-bit latch, LCB included
// *!****************************************************************

`include "tri_a2o.vh"

module tri_rlmreg_p(vd, gd, nclk, act, force_t, thold_b, d_mode, sg, delay_lclkr, mpw1_b, mpw2_b, scin, din, scout, dout);
   parameter                    WIDTH = 4;
   parameter                    OFFSET = 0;		//starting bit
   parameter                    INIT = 0;		// will be converted to the least signficant
                                                        // 31 bits of init_v
   parameter                    IBUF = 1'b0;		//inverted latch IOs, if set to true.
   parameter                    DUALSCAN = "";	// if "S", marks data ports as scan for Moebius
   parameter                    NEEDS_SRESET = 1;	// for inferred latches
   parameter                    DOMAIN_CROSSING = 0;

   //wtf trying to fix verilator clock gating bug(?) booting a2o; seeing
   parameter                    ALWAYS_ACT = 0;   //wtf 1: override clock gating - can't if truly functional!

   inout                        vd;
   inout                        gd;
   input [0:`NCLK_WIDTH-1]      nclk;
   input                        act;		// 1: functional, 0: no clock
   input                        force_t;	// 1: force LCB active
   input                        thold_b;	// 1: functional, 0: no clock
   input                        d_mode;	// 1: disable pulse mode, 0: pulse mode
   input                        sg;		// 0: functional, 1: scan
   input                        delay_lclkr;	// 0: functional
   input                        mpw1_b;	// pulse width control bit
   input                        mpw2_b;	// pulse width control bit
   input [OFFSET:OFFSET+WIDTH-1]  scin;		// scan in
   input [OFFSET:OFFSET+WIDTH-1]  din;		// data in
   output [OFFSET:OFFSET+WIDTH-1] scout;
   output [OFFSET:OFFSET+WIDTH-1] dout;

 /* verilator lint_off WIDTH */
   parameter [0:WIDTH-1]        init_v = INIT;  //wtf causes width mismatch warnings; would have to handle both greater and less than 32 bit cases
 /* verilator lint_on WIDTH */
   parameter [0:WIDTH-1]        ZEROS = {WIDTH{1'b0}};

   // tri_rlmreg_p

   generate
     wire                       sreset;
     wire [0:WIDTH-1]           int_din;
     reg [0:WIDTH-1]            int_dout;
     wire [0:WIDTH-1]           vact;
     wire [0:WIDTH-1]           vact_b;
     wire [0:WIDTH-1]           vsreset;
     wire [0:WIDTH-1]           vsreset_b;
     wire [0:WIDTH-1]           vthold;
     wire [0:WIDTH-1]           vthold_b;
       (* analysis_not_referenced="true" *)
     wire [0:WIDTH]             unused;

     if (NEEDS_SRESET == 1)
     begin : rst
       assign sreset = nclk[1];
     end
     if (NEEDS_SRESET != 1)
     begin : no_rst
       assign sreset = 1'b0;
     end

     assign vsreset = {WIDTH{sreset}};
     assign vsreset_b = {WIDTH{~sreset}};

     if (IBUF == 1'b1)
     begin : cib
       assign int_din = (vsreset_b & (~din)) | (vsreset & init_v);
     end
     if (IBUF == 1'b0)
     begin : cnib
       assign int_din = (vsreset_b & din) | (vsreset & init_v);
     end

     assign vact = {WIDTH{act | force_t | ALWAYS_ACT == 1}};
     assign vact_b = {WIDTH{~(act | force_t | ALWAYS_ACT == 1)}};

     assign vthold_b = {WIDTH{thold_b}};
     assign vthold = {WIDTH{~thold_b}};

     always @(posedge nclk[0])
     begin: l
       int_dout <= (((vact & vthold_b) | vsreset) & int_din) | (((vact_b | vthold) & vsreset_b) & int_dout);
     end

     if (IBUF == 1'b1)
     begin : cob
       assign dout = (~int_dout);
     end

     if (IBUF == 1'b0)
     begin : cnob
       assign dout = int_dout;
     end

     assign scout = ZEROS;

     assign unused[0] = d_mode | sg | delay_lclkr | mpw1_b | mpw2_b | vd | gd | (|nclk);
     assign unused[1:WIDTH] = scin;

   endgenerate
endmodule