[dv] Add riscv_rf_ctrl_intg_test

This tests new hardening added to the register file around read and
write control signals.

dv/uvm/core_ibex/riscv_dv_extension/testlist.yaml

@@ -689,6 +689,21 @@
   rtl_params:
     SecureIbex: 1
 
+- test: riscv_rf_ctrl_intg_test
+  description: >
+    Randomly corrupt one of the register file write and read enables signals in the middle of program execution
+  iterations: 15
+  gen_test: riscv_rand_instr_test
+  gen_opts: >
+    +instr_cnt=10000
+    +num_of_sub_program=5
+    +gen_all_csrs_by_default=1
+    +add_csr_write=MSTATUS,MEPC,MCAUSE,MTVAL,0x7c0,0x7c1
+    +no_csr_instr=0
+  rtl_test: core_ibex_rf_ctrl_intg_test
+  rtl_params:
+    SecureIbex: 1
+
 - test: riscv_icache_intg_test
   description: >
     Randomly corrupt the instruction cache once in the middle of program execution

dv/uvm/core_ibex/tb/core_ibex_tb_top.sv

@@ -161,6 +161,8 @@ module core_ibex_tb_top;
   `ASSERT(NoAlertsTriggered,
     !dut_if.alert_minor && !dut_if.alert_major_internal && !dut_if.alert_major_bus, clk, !rst_n)
   `DV_ASSERT_CTRL("tb_no_alerts_triggered", core_ibex_tb_top.NoAlertsTriggered)
+  `DV_ASSERT_CTRL("tb_rf_rd_mux_a_onehot", core_ibex_tb_top.dut.u_ibex_top.gen_regfile_ff.register_file_i.gen_rdata_mux_check.u_rdata_a_mux.SelIsOnehot_A)
+  `DV_ASSERT_CTRL("tb_rf_rd_mux_b_onehot", core_ibex_tb_top.dut.u_ibex_top.gen_regfile_ff.register_file_i.gen_rdata_mux_check.u_rdata_b_mux.SelIsOnehot_A)
 
   assign dut.u_ibex_top.u_ibex_core.u_fcov_bind.rf_we_glitch_err =
     dut.u_ibex_top.rf_alert_major_internal;

dv/uvm/core_ibex/tests/core_ibex_test_lib.sv

@@ -199,6 +199,81 @@ class core_ibex_rf_intg_test extends core_ibex_base_test;
 
 endclass
 
+class core_ibex_rf_ctrl_intg_test extends core_ibex_base_test;
+  `uvm_component_utils(core_ibex_rf_ctrl_intg_test)
+  `uvm_component_new
+
+  uvm_report_server rs;
+
+  virtual task send_stimulus();
+    int          rnd_delay;
+    int unsigned bit_idx;
+    logic [31:0] orig_val, glitch_val;
+    logic        alert_major_internal;
+    string       glitch_path, alert_major_internal_path;
+    string       ctrl_signals[];
+    string       ctrl_signal;
+    int unsigned ctrl_signal_idx;
+    string       top_path = "core_ibex_tb_top.dut.u_ibex_top";
+    string       ibex_rf_path = {top_path, ".gen_regfile_ff.register_file_i"};
+
+    ctrl_signals = {
+      "we_a_dec",
+      "gen_rdata_mux_check.raddr_onehot_a",
+      "gen_rdata_mux_check.raddr_onehot_b"
+    };
+
+    `DV_CHECK_STD_RANDOMIZE_WITH_FATAL(ctrl_signal_idx, ctrl_signal_idx < ctrl_signals.size();)
+    `DV_CHECK_STD_RANDOMIZE_WITH_FATAL(rnd_delay, rnd_delay > 1000; rnd_delay < 10_000;)
+
+    ctrl_signal = ctrl_signals[ctrl_signal_idx];
+
+    glitch_path = $sformatf("%s.%s", ibex_rf_path, ctrl_signal);
+
+    vseq.start(env.vseqr);
+    clk_vif.wait_n_clks(rnd_delay);
+
+    `uvm_info(`gfn, $sformatf("Reading value of %s", glitch_path), UVM_LOW)
+    `DV_CHECK_FATAL(uvm_hdl_read(glitch_path, orig_val));
+    `uvm_info(`gfn, $sformatf("Read %x", orig_val), UVM_LOW)
+
+    `DV_CHECK_STD_RANDOMIZE_WITH_FATAL(bit_idx, bit_idx < 32;)
+
+    glitch_val = orig_val;
+    glitch_val[bit_idx] = ~glitch_val[bit_idx];
+
+    // Disable TB assertion for alerts.
+    `DV_ASSERT_CTRL_REQ("tb_no_alerts_triggered", 1'b0)
+    // Disable one-hot check assertions for RF muxes
+    `DV_ASSERT_CTRL_REQ("tb_rf_rd_mux_a_onehot", 1'b0)
+    `DV_ASSERT_CTRL_REQ("tb_rf_rd_mux_b_onehot", 1'b0)
+
+    `uvm_info(`gfn, $sformatf("Forcing %s to value 'h%0x", glitch_path, glitch_val), UVM_LOW)
+    `DV_CHECK_FATAL(uvm_hdl_force(glitch_path, glitch_val));
+
+    // Leave glitch applied for one clock cycle.
+    clk_vif.wait_n_clks(1);
+
+    // Check that the alert matches our expectation.
+    alert_major_internal_path = $sformatf("%s.alert_major_internal_o", top_path);
+    `DV_CHECK_FATAL(uvm_hdl_read(alert_major_internal_path, alert_major_internal))
+    `DV_CHECK_EQ_FATAL(alert_major_internal, 1'b1, "Major alert did not fire!")
+
+    // Release glitch.
+    `DV_CHECK_FATAL(uvm_hdl_release(glitch_path))
+    `uvm_info(`gfn, $sformatf("Releasing force of %s", glitch_path), UVM_LOW)
+
+    // Re-enable TB assertion for alerts.
+    `DV_ASSERT_CTRL_REQ("tb_no_alerts_triggered", 1'b1)
+
+    // Complete the test at this point because cosimulation does not model faults so will cause
+    // a mis-match and a test failure.
+    rs = uvm_report_server::get_server();
+    rs.report_summarize();
+    $finish();
+  endtask
+endclass
+
 // Test that corrupts the instruction cache and checks that an appropriate alert occurs.
 class core_ibex_icache_intg_test extends core_ibex_base_test;