Subversion Repositories bluespec-reedsolomon

//----------------------------------------------------------------------//

// The MIT License 

// 

// Copyright (c) 2008 Abhinav Agarwal, Alfred Man Cheuk Ng

// Contact: abhiag@gmail.com

// 

// Permission is hereby granted, free of charge, to any person 

// obtaining a copy of this software and associated documentation 

// files (the "Software"), to deal in the Software without 

// restriction, including without limitation the rights to use,

// copy, modify, merge, publish, distribute, sublicense, and/or sell

// copies of the Software, and to permit persons to whom the

// Software is furnished to do so, subject to the following conditions:

// 

// The above copyright notice and this permission notice shall be

// included in all copies or substantial portions of the Software.

// 

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

// OTHER DEALINGS IN THE SOFTWARE.

//----------------------------------------------------------------------//

#include "global_rs.h"

#include "gf_arith.h"

#include "berlekamp.h"

#pragma design

void gfmult_array_array_hw (unsigned char res_vec[tt+2], unsigned char in_vec0[tt+2], unsigned char in_vec1[tt+2])

{

  #pragma unroll yes

  for (int i = 0; i < tt+2; ++i)

    res_vec[i] = gfmult_hw(in_vec0[i],in_vec1[i]);

}

#pragma design

void gfmult_scalar_array_hw1 (unsigned char res_vec[tt+2], unsigned char val, unsigned char in_vec[tt+2])

{

  #pragma unroll yes

  for (int i = 0; i < tt+2; ++i)

    res_vec[i] = gfmult_hw(val,in_vec[i]);

}

#pragma design

void gfmult_scalar_array_hw2 (unsigned char res_vec[tt+2], unsigned char val, unsigned char in_vec[tt+2])

{

  #pragma unroll yes

  for (int i = 0; i < tt+2; ++i)

    res_vec[i] = gfmult_hw(val,in_vec[i]);

}

#pragma design

void gfadd_array_array_hw1 (unsigned char in_vec0[tt+2], unsigned char in_vec1[tt+2])

{

  #pragma unroll yes

  for (int i = 0; i < tt+2; ++i)

    in_vec0[i] = gfadd_hw(in_vec0[i], in_vec1[i]);

}

#pragma design

void gfadd_array_array_hw2 (unsigned char in_vec0[tt+2], unsigned char in_vec1[tt+2])

{

  #pragma unroll yes

  for (int i = 0; i < tt+2; ++i)

    in_vec0[i] = gfadd_hw(in_vec0[i], in_vec1[i]);

}

#pragma design

unsigned char gfsum_array_hw (unsigned char in_vec[tt+2])

{

  unsigned char res = 0;

  #pragma unroll yes

  for (int i = 0; i < tt+2; ++i)

    res = gfadd_hw(res, in_vec[i]);

  return res;

}

#pragma hls_design 

void berlekamp (unsigned char t, unsigned char s[2*tt], unsigned char c_out[tt], unsigned char w_out[tt])

{

  unsigned char l = 0;

  unsigned char p[tt+2];

  unsigned char a[tt+2];

  unsigned char t1[tt+2];

  unsigned char t2[tt+2];

  unsigned char syn_shift_reg[tt+2];

  unsigned char temp[tt+2];

  unsigned char c[tt+2];

  unsigned char w[tt+2];

  c[0] = 1;

  p[0] = 1;

  w[0] = 0;

  a[0] = 1;

  syn_shift_reg[0] = 0;

  temp[0] = 0;

  #pragma unroll true

  BerlInit: for (int i = 1; i < tt+2; i++)

  {

    c [i] = 0;

    w [i] = 0;

    p [i] = 0;

    a [i] = 0;

    t1[i] = 0;

    t2[i] = 0;

    syn_shift_reg[i] = 0;

    temp[i] = 0;

  }

  unsigned char dstar = 1;

  unsigned char d = 0;

  unsigned char ddstar = 1;

   BerlOuter:

   for (int i = 0; i < 2*tt; i++ )

   {

      #pragma unroll true 

      BerlShift: for (int k = tt+1; k > 0; --k)

      {

          syn_shift_reg[k] = syn_shift_reg[k-1];

          p[k] = p[k-1];

          a[k] = a[k-1];

      }

      syn_shift_reg[0] = s[i];

      p[0] = 0;

      a[0] = 0;

//      d = 0;

//      BerlComplex1: for (int k = 0; k < tt+2; ++k)

//          d = gfadd_hw(d, gfmult_hw(c[k], syn_shift_reg[k]));

      gfmult_array_array_hw(temp, c, syn_shift_reg);

      d = gfsum_array_hw(temp);

      if (d != 0)

      {

             ddstar = gfmult_hw(d, dstar);

             #pragma unroll true

             BerlSimple1: for (int k = 0; k < tt+2; ++k)

         {

               t1 [k] = p [k];

               t2 [k] = a [k];

         }

         if (i + 1 > 2*l)

         {

                l = i - l + 1;

            #pragma unroll true

            BerlSimple2: for (int k = 0; k < tt+2; ++k)

            {

               p [k] = c [k];

               a [k] = w [k];

            }

            dstar = gfinv_lut ( d );

         }

//       BerlComplex2: for (int k = 0; k < tt+2; ++k)

//       {

//         c[k] = gfadd_hw(c[k], gfmult_hw(ddstar,t1[k]));

//         w[k] = gfadd_hw(w[k], gfmult_hw(ddstar,t2[k]));

//       }

         gfmult_scalar_array_hw1(temp, ddstar, t1);

         gfadd_array_array_hw1(c,temp);

         gfmult_scalar_array_hw2(temp, ddstar, t2);

         gfadd_array_array_hw2(w,temp);

      }

   }

   #pragma unroll true

   BerlCopy: for (int k = 0; k < tt; ++k)

   {

       c_out[k] = c[k+1];

       w_out[k] = w[k+1];

   }

}