[dv/clkmgr] Ignore coverage crosses that are unrealistic

The CSRs cannot be modified in low power since the CPU is off.

Signed-off-by: Guillermo Maturana <[email protected]>

hw/ip/clkmgr/dv/env/clkmgr_env_cov.sv

@@ -19,7 +19,10 @@ class clkmgr_peri_cg_wrap;
  ip_clk_en_cp: coverpoint ip_clk_en;
  scanmode_cp: coverpoint scanmode;
 
- peri_cross: cross csr_enable_cp, ip_clk_en_cp, scanmode_cp;
+ peri_cross: cross csr_enable_cp, ip_clk_en_cp, scanmode_cp{
+ // The enable CSRs cannot be manipulated in low power mode.
+ ignore_bins ignore_enable_off = peri_cross with (csr_enable_cp == 1 && ip_clk_en_cp == 0);
+ }
  endgroup
 
  function new(string name);
@@ -48,7 +51,10 @@ class clkmgr_trans_cg_wrap;
  idle_cp: coverpoint idle;
 
  trans_cross: cross csr_hint_cp, ip_clk_en_cp, scanmode_cp, idle_cp{
- ignore_bins ignore = trans_cross with (idle_cp == 0 && ip_clk_en_cp == 0);
+ // If the clock is disabled the unit must be idle.
+ ignore_bins ignore_idle_off = trans_cross with (idle_cp == 0 && ip_clk_en_cp == 0);
+ // The hint CSRs cannot be manipulated in low power mode.
+ ignore_bins ignore_enable_off = trans_cross with (csr_hint_cp == 1 && ip_clk_en_cp == 0);
  }
  endgroup