localparam MAX_LFSR_WIDTH       = 36;

// Number of LFSR modules required
localparam NUM_LFSR                     = num_lfsr(DATA_WIDTH);
...
// Calculate the number of LFSR modules needed for the specified width
function integer num_lfsr;
         input integer data_width;
         begin
                 num_lfsr = 1;
                 while ((data_width + num_lfsr - 1) / num_lfsr > MAX_LFSR_WIDTH)
                         num_lfsr = num_lfsr * 2;
         end
endfunction

%Error: lfsr_wrapper.sv:44: Expecting expression to be constant, but can't determine constant for FUNCREF 'num_lfsr'
%Error: lfsr_wrapper.sv:95: ... Location of non-constant VARREF 'MAX_LFSR_WIDTH': Language violation: reference to non-function-local variable