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* library with functions for calculating parameters for CIC filter and Hogenauer pruning
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* library with functions for calculating parameters for CIC filter and Hogenauer pruning
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*/
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*/
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`ifndef _CIC_FUNCTIONS_VH_
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`ifndef _CIC_FUNCTIONS_VH_
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`define _CIC_FUNCTIONS_VH_
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`define _CIC_FUNCTIONS_VH_
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`define M_PI 3.14159265359 // not all simulator defines PI
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`define M_PI 3.14159265359 // not all simulator defines PI
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/*********************************************************************************************/
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function reg unsigned [127 : 0] nchoosek; ///< Binomial coefficient
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function reg unsigned [127 : 0] nchoosek; ///< Binomial coefficient
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input integer n;
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input integer n;
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input integer k;
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input integer k;
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reg unsigned [127:0] tmp;
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reg unsigned [127:0] tmp;
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integer i;
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integer i;
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for (i = 1; i <= (n - k); i = i + 1)
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for (i = 1; i <= (n - k); i = i + 1)
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tmp = tmp * (k + i) / i;
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tmp = tmp * (k + i) / i;
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nchoosek = tmp;
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nchoosek = tmp;
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function integer clog2_l;
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function integer clog2_l;
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input reg unsigned [127:0] depth;
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input reg unsigned [127:0] depth;
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reg unsigned [127:0] i;
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reg unsigned [127:0] i;
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begin
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begin
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clog2_l = 0;
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clog2_l = 0;
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i = i >> 1;
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i = i >> 1;
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end else
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end else
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clog2_l = -1;
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clog2_l = -1;
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function integer B_max_calc;
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function integer B_max_calc;
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input integer N;
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input integer N;
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input integer R;
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input integer R;
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input integer M;
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input integer M;
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input integer INP_DW;
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input integer INP_DW;
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reg unsigned [127:0] RMpN;
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reg unsigned [127:0] RMpN;
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begin
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begin
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RMpN = (R * M) ** N;
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RMpN = (R * M) ** N;
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B_max_calc = clog2_l(RMpN) + INP_DW - 1;
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B_max_calc = clog2_l(RMpN) + INP_DW - 1;
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//$display("B_max_calc: N=%2d, R=%2d, M=%2d, ret=%2d", N, R, M, B_max_calc);
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function integer B_out_calc;
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function integer B_out_calc;
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input integer N;
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input integer N;
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input integer R;
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input integer R;
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input integer M;
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input integer M;
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input integer INP_DW;
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input integer INP_DW;
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input integer OUT_DW;
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input integer OUT_DW;
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begin
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begin
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B_out_calc = B_max_calc(N, R, M, OUT_DW) - B(2 * N, R, M, N, INP_DW, OUT_DW) + 1;
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B_out_calc = B_max_calc(N, R, M, OUT_DW) - B_calc(2 * N, N, R, M, INP_DW, OUT_DW) + 1;
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function integer flog2_l;
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function integer flog2_l;
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input reg unsigned [127:0] depth;
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input reg unsigned [127:0] depth;
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reg unsigned [127:0] i;
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reg unsigned [127:0] i;
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begin
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begin
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i = depth;
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i = depth;
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for(flog2_l = 0; i > 1; flog2_l = flog2_l + 1)
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for(flog2_l = 0; i > 1; flog2_l = flog2_l + 1)
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i = i >> 1;
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i = i >> 1;
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function reg signed [127:0] h;
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function reg signed [127:0] h_calc;
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input integer j;
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input integer j;
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input integer k;
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input integer k;
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input integer N;
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input integer R;
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input integer R;
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input integer M;
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input integer M;
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input integer N;
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integer c_stop;
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integer c_stop;
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integer i;
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integer i;
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reg signed [127:0] tmp;
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reg signed [127:0] tmp;
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reg signed [127:0] prod_1;
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reg signed [127:0] prod_1;
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reg signed [127:0] prod_2;
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reg signed [127:0] prod_2;
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Line 96... |
end
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end
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else begin
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else begin
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tmp = nchoosek(2 * N + 1 - j, k);
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tmp = nchoosek(2 * N + 1 - j, k);
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if (k % 2) tmp = -tmp;
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if (k % 2) tmp = -tmp;
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end
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end
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h = tmp;
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h_calc = tmp;
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function reg signed [127:0] F_sq; ///< F()**2
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function reg signed [127:0] F_sq_calc; ///< F()**2
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input integer j;
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input integer j;
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input integer N;
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input integer R;
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input integer R;
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input integer M;
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input integer M;
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input integer N;
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integer c_stop;
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integer c_stop;
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reg signed [127:0] tmp;
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reg signed [127:0] tmp;
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integer i;
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integer i;
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reg signed [127:0] h_jk;
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reg signed [127:0] h_jk;
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begin
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begin
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Line 116... |
if (j <= N)
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if (j <= N)
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c_stop = (((R * M -1 ) * N) + j - 1);
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c_stop = (((R * M -1 ) * N) + j - 1);
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else
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else
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c_stop = 2 * N + 1 - j;
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c_stop = 2 * N + 1 - j;
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for (i = 0;i <= c_stop; i = i + 1) begin
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for (i = 0;i <= c_stop; i = i + 1) begin
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h_jk = h(j, i, R, M, N);
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h_jk = h_calc(j, i, N, R, M);
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tmp = tmp + h_jk ** 2;
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tmp = tmp + h_jk ** 2;
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end
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end
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F_sq = tmp;
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F_sq_calc = tmp;
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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function integer B;
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function integer B_calc;
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input integer j;
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input integer j;
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input integer N;
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input integer R;
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input integer R;
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input integer M;
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input integer M;
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input integer N;
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input integer dw_in;
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input integer dw_in;
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input integer dw_out;
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input integer dw_out;
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integer B_max;
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integer B_max;
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reg signed [127:0] sigma_T_2Np1_sq;
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reg signed [127:0] sigma_T_2Np1_sq;
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reg signed [127:0] B_2Np1;
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reg signed [127:0] B_2Np1;
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reg signed [127:0] B_exp_real;
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reg signed [127:0] B_exp_real;
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integer B_out;
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integer B_out;
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reg signed [127:0] F_sq_j;
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reg signed [127:0] F_sq_j;
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reg signed [127:0] F_sq_2Np1;
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reg signed [127:0] F_sq_2Np1;
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begin
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begin
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if (j <= 0) begin
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B_calc = 0;
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end else begin
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B_max = B_max_calc(N, R, M, dw_in);
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B_max = B_max_calc(N, R, M, dw_in);
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if (j == 2 * N + 1) begin
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if (j == 2 * N + 1) begin
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B = B_max - dw_out + 1;
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B_calc = B_max - dw_out + 1;
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end else begin
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end else begin
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B_2Np1 = B_max - dw_out + 1;
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B_2Np1 = B_max - dw_out + 1;
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F_sq_j = F_sq(j, R, M, N);
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F_sq_j = F_sq_calc(j, N, R, M);
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F_sq_2Np1 = F_sq(2 * N + 1, R, M, N);
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F_sq_2Np1 = F_sq_calc(2 * N + 1, N, R, M);
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sigma_T_2Np1_sq = (128'b1 << (2 * B_2Np1)) * F_sq_2Np1 / 12;
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sigma_T_2Np1_sq = (128'b1 << (2 * B_2Np1)) * F_sq_2Np1 / 12;
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B_exp_real = (sigma_T_2Np1_sq / F_sq_j * 6 / N);
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B_exp_real = (sigma_T_2Np1_sq / F_sq_j * 6 / N);
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B_out = flog2_l(B_exp_real) / 2;
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B_out = flog2_l(B_exp_real) / 2;
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B = B_out;
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B_calc = B_out;
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end
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end
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end
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end
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end
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endfunction
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endfunction
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/*********************************************************************************************/
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`endif
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`endif
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No newline at end of file
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No newline at end of file
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