diff --git a/checks/genchecks.py b/checks/genchecks.py
index b7069f1..27567ed 100644
--- a/checks/genchecks.py
+++ b/checks/genchecks.py
@@ -33,6 +33,7 @@
 dumpsmt2 = False
 sbycmd = "sby"
 config = dict()
+mode = "bmc"
 
 if len(sys.argv) > 1:
     assert len(sys.argv) == 2
@@ -83,6 +84,11 @@
             assert len(line) == 1
             dumpsmt2 = True
 
+        elif line[0] == "mode":
+            assert len(line) == 2
+            if line[1] == "prove":
+                mode = line[1]
+
         else:
             print(line)
             assert 0
@@ -119,6 +125,7 @@ def print_hfmt(f, text, **kwargs):
 hargs["xlen"] = xlen
 hargs["ilen"] = ilen
 hargs["append"] = 0
+hargs["mode"] = mode
 
 instruction_checks = set()
 consistency_checks = set()
@@ -178,7 +185,7 @@ def check_insn(insn, chanidx, csr_mode=False):
     with open("%s/%s.sby" % (cfgname, check), "w") as sby_file:
         print_hfmt(sby_file, """
                 : [options]
-                : mode bmc
+                : mode @mode@
                 : expect pass,fail
                 : append @append@
                 : tbtop wrapper.uut
@@ -231,6 +238,9 @@ def check_insn(insn, chanidx, csr_mode=False):
                 : `define RISCV_FORMAL_CHANNEL_IDX @channel@
         """, **hargs)
 
+        if mode == "prove":
+            print("`define RISCV_FORMAL_UNBOUNDED", file=sby_file)
+
         for csr in sorted(csrs):
             print("`define RISCV_FORMAL_CSR_%s" % csr.upper(), file=sby_file)
 
@@ -337,7 +347,7 @@ def check_cons(check, chanidx=None, start=None, trig=None, depth=None, csr_mode=
     with open("%s/%s.sby" % (cfgname, check), "w") as sby_file:
         print_hfmt(sby_file, """
                 : [options]
-                : mode bmc
+                : mode @mode@
                 : expect pass,fail
                 : append @append@
                 : tbtop wrapper.uut
@@ -386,6 +396,9 @@ def check_cons(check, chanidx=None, start=None, trig=None, depth=None, csr_mode=
                 : `define RISCV_FORMAL_CHECK_CYCLE @depth@
         """, **hargs)
 
+        if mode == "prove":
+            print("`define RISCV_FORMAL_UNBOUNDED", file=sby_file)
+
         for csr in sorted(csrs):
             print("`define RISCV_FORMAL_CSR_%s" % csr.upper(), file=sby_file)
 
@@ -467,4 +480,3 @@ def checks_key(check):
         print(".PHONY: %s" % check, file=mkfile)
 
 print("Generated %d checks." % (len(consistency_checks) + len(instruction_checks)))
-
diff --git a/checks/rvfi_testbench.sv b/checks/rvfi_testbench.sv
index 5f8e3d9..47bd78f 100644
--- a/checks/rvfi_testbench.sv
+++ b/checks/rvfi_testbench.sv
@@ -13,6 +13,14 @@
 // OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 module rvfi_testbench (
+	`ifdef RISCV_FORMAL_UNBOUNDED
+	`ifdef RISCV_FORMAL_TRIG_CYCLE
+		input trig,
+	`endif
+	`ifdef RISCV_FORMAL_CHECK_CYCLE
+		input check,
+	`endif
+	`endif
 	input clock, reset
 );
 	`RVFI_WIRES
@@ -32,10 +40,18 @@ module rvfi_testbench (
 		.clock  (clock),
 		.reset  (cycle < `RISCV_FORMAL_RESET_CYCLES),
 `ifdef RISCV_FORMAL_TRIG_CYCLE
+`ifdef RISCV_FORMAL_UNBOUNDED
+		.trig   (trig),
+`else
 		.trig   (cycle == `RISCV_FORMAL_TRIG_CYCLE),
 `endif
+`endif
 `ifdef RISCV_FORMAL_CHECK_CYCLE
+`ifdef RISCV_FORMAL_UNBOUNDED
+		.check   (check),
+`else
 		.check  (cycle == `RISCV_FORMAL_CHECK_CYCLE),
+`endif
 `endif
 		`RVFI_CONN
 	);