diff --git a/sys/riscv/include/sbi.h b/sys/riscv/include/sbi.h
--- a/sys/riscv/include/sbi.h
+++ b/sys/riscv/include/sbi.h
@@ -166,10 +166,10 @@
 extern u_long sbi_impl_id;
 extern u_long sbi_impl_version;
 
-static __inline long
-sbi_probe_extension(long id)
+static __inline bool
+sbi_has_extension(long id)
 {
-	return (SBI_CALL1(SBI_EXT_ID_BASE, SBI_BASE_PROBE_EXTENSION, id).value);
+	return (SBI_CALL1(SBI_EXT_ID_BASE, SBI_BASE_PROBE_EXTENSION, id).value != 0);
 }
 
 /* TIME extension functions. */
diff --git a/sys/riscv/riscv/machdep.c b/sys/riscv/riscv/machdep.c
--- a/sys/riscv/riscv/machdep.c
+++ b/sys/riscv/riscv/machdep.c
@@ -201,7 +201,7 @@
 	 * simple wfi loop.
 	 */
 	intr_disable();
-	if (sbi_probe_extension(SBI_EXT_ID_HSM) != 0)
+	if (sbi_has_extension(SBI_EXT_ID_HSM))
 		sbi_hsm_hart_stop();
 	for (;;)
 		__asm __volatile("wfi");
diff --git a/sys/riscv/riscv/mp_machdep.c b/sys/riscv/riscv/mp_machdep.c
--- a/sys/riscv/riscv/mp_machdep.c
+++ b/sys/riscv/riscv/mp_machdep.c
@@ -468,7 +468,7 @@
 	 * Depending on the SBI implementation, APs are waiting either in
 	 * locore.S or to be activated explicitly, via SBI call.
 	 */
-	if (sbi_probe_extension(SBI_EXT_ID_HSM) != 0) {
+	if (sbi_has_extension(SBI_EXT_ID_HSM)) {
 		start_addr = pmap_kextract((vm_offset_t)mpentry);
 		error = sbi_hsm_hart_start(hart, start_addr, 0);
 		if (error != 0) {
diff --git a/sys/riscv/riscv/sbi.c b/sys/riscv/riscv/sbi.c
--- a/sys/riscv/riscv/sbi.c
+++ b/sys/riscv/riscv/sbi.c
@@ -283,37 +283,37 @@
 	mimpid = sbi_get_mimpid().value;
 
 	/* Probe for legacy replacement extensions. */
-	if (sbi_probe_extension(SBI_EXT_ID_TIME) != 0)
+	if (sbi_has_extension(SBI_EXT_ID_TIME))
 		has_time_extension = true;
-	if (sbi_probe_extension(SBI_EXT_ID_IPI) != 0)
+	if (sbi_has_extension(SBI_EXT_ID_IPI))
 		has_ipi_extension = true;
-	if (sbi_probe_extension(SBI_EXT_ID_RFNC) != 0)
+	if (sbi_has_extension(SBI_EXT_ID_RFNC))
 		has_rfnc_extension = true;
-	if (sbi_probe_extension(SBI_EXT_ID_SRST) != 0)
+	if (sbi_has_extension(SBI_EXT_ID_SRST))
 		has_srst_extension = true;
 
 	/*
 	 * Probe for legacy extensions. We still rely on many of them to be
 	 * implemented, but this is not guaranteed by the spec.
 	 */
-	KASSERT(has_time_extension || sbi_probe_extension(SBI_SET_TIMER) != 0,
+	KASSERT(has_time_extension || sbi_has_extension(SBI_SET_TIMER),
 	    ("SBI doesn't implement sbi_set_timer()"));
-	KASSERT(sbi_probe_extension(SBI_CONSOLE_PUTCHAR) != 0,
+	KASSERT(sbi_has_extension(SBI_CONSOLE_PUTCHAR),
 	    ("SBI doesn't implement sbi_console_putchar()"));
-	KASSERT(sbi_probe_extension(SBI_CONSOLE_GETCHAR) != 0,
+	KASSERT(sbi_has_extension(SBI_CONSOLE_GETCHAR),
 	    ("SBI doesn't implement sbi_console_getchar()"));
-	KASSERT(has_ipi_extension || sbi_probe_extension(SBI_SEND_IPI) != 0,
+	KASSERT(has_ipi_extension || sbi_has_extension(SBI_SEND_IPI),
 	    ("SBI doesn't implement sbi_send_ipi()"));
 	KASSERT(has_rfnc_extension ||
-	    sbi_probe_extension(SBI_REMOTE_FENCE_I) != 0,
+	    sbi_has_extension(SBI_REMOTE_FENCE_I),
 	    ("SBI doesn't implement sbi_remote_fence_i()"));
 	KASSERT(has_rfnc_extension ||
-	    sbi_probe_extension(SBI_REMOTE_SFENCE_VMA) != 0,
+	    sbi_has_extension(SBI_REMOTE_SFENCE_VMA),
 	    ("SBI doesn't implement sbi_remote_sfence_vma()"));
 	KASSERT(has_rfnc_extension ||
-	    sbi_probe_extension(SBI_REMOTE_SFENCE_VMA_ASID) != 0,
+	    sbi_has_extension(SBI_REMOTE_SFENCE_VMA_ASID),
 	    ("SBI doesn't implement sbi_remote_sfence_vma_asid()"));
-	KASSERT(has_srst_extension || sbi_probe_extension(SBI_SHUTDOWN) != 0,
+	KASSERT(has_srst_extension || sbi_has_extension(SBI_SHUTDOWN),
 	    ("SBI doesn't implement a shutdown or reset extension"));
 }