Generic Cover Bin generation

Coverage
,
1

Hi All,
I want to create bin for coverage with below requirements

  1. Requirement 1

Let take a variable bit [n-1:0] xyz.
Where n can vary from 1-20.

Bins will be like for n = 3 
bin1 = {0,1};
bin2 = {2,3};
bin3 = {4,5,6,7};
  1. Requirement 2

Transition coverage of ranges for above xyz
bin1 = (0,1 => 2,3);
bin2 = (2,3 => 4,5,6,7);

Note - Based on parameter “n” I want to generate coverbins.
Looking for a generic solution.

Thanks

2

In reply to hisingh:

This can be done by creating an array of covergroups.


let range(v,i) = v inside { [(i==0 ? 0: 2**i):2**(i+1)-1]}; // '?:' fix so 2**0 is 0
covergroup m(int I, ref cp);
req1: coverpoint range(cp,I) {
  bins hit = {1};
}
req2: coverpoint {range(cp,I),range(cp,I+1} {
  bins hit = (2'b10 => 2'b01);
endgroup

m cg[n];
foreach(cg[i]) cg[i] = new(i,xyz);

Just realized that you will need another fix so that req2 has one less coverpoint when I=N-1.

3

In reply to dave_59:

Can you please elaborate range(v,i). If its function or struct or any keyword?

4

In reply to hisingh:

The let construct is almost like a macro, but with more formal semantics. See section 11.12 Let construct in the IEEE 1800-2017 SystemVerilog LRM