One example script for SPFM and LFM calculation:
set_log_file("spfm_lfm.log"); # Set log file name read_library("art.5nm.lib"); # Read in liberty file read_design('-imp', 'ecc_process.v'); # Read in the design block set_top("ecc_top"); # Set the top module name create_clock("data_clk", 2); set_pin_constant("test_mode", 0); # Set pin constraint set_observe_points("data_out*"); # data_out[31:0] affects functional safety set_observe_points("synd_out"); # synd_out affects functional safety set_detect_points("sb_err_o"); # Safety mechanism detecting output set_detect_points("db_err_o"); # Safety mechanism detecting output verify_faults("-full"); # Calculate and print SPFM and LFM, Use verify_faults("-coi") for fast SPFM/LFM calculation gexit;
The API verify_faults can run on an individual fault to check if the fault can propagate to the observation points. If the fault is observable, a VCD file can be dumped to show how to toggle the input ports cycle by cycle to propagate the fault. All internal signals waveforms are captured in the VCD file.
The following script is to check if one SEU fault can propagate. If yes, a VCD file is dumped:
set_log_file("spfm_lfm.log"); # Set log file name read_library("art.5nm.lib"); # Read in liberty file read_design('-imp', 'ecc_process.v'); # Read in the design block set_top("ecc_top"); # Set the top module name set_pin_constant("test_mode", 0); # Set pin constraint set_observe_points("data_out*"); # data_out[31:0] affects functional safety set_observe_points("synd_out"); # synd_out affects functional safety # To check if the fault can be propagated to the detect points, set_observe_points on the detect points verify_faults("u_ecc_ops/bit_reg:SEU", "-vcd", "debug_seu.vcd"); # Check if the Single Event Upset on the flop can propagate gexit;
