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
@@ -532,9 +532,9 @@
 void
 cpu_mp_setmaxid(void)
 {
-#ifdef FDT
 	int cores;
 
+#ifdef FDT
 	cores = ofw_cpu_early_foreach(cpu_check_mmu, true);
 	if (cores > 0) {
 		cores = MIN(cores, MAXCPU);
@@ -543,12 +543,19 @@
 		mp_ncpus = cores;
 		mp_maxid = cores - 1;
 		cpu_enum_method = CPUS_FDT;
-		return;
-	}
+	} else
 #endif
+	{
+		if (bootverbose)
+			printf("No CPU data, limiting to 1 core\n");
+		mp_ncpus = 1;
+		mp_maxid = 0;
+	}
 
-	if (bootverbose)
-		printf("No CPU data, limiting to 1 core\n");
-	mp_ncpus = 1;
-	mp_maxid = 0;
+	if (TUNABLE_INT_FETCH("hw.ncpu", &cores)) {
+		if (cores > 0 && cores < mp_ncpus) {
+			mp_ncpus = cores;
+			mp_maxid = cores - 1;
+		}
+	}
 }