Index: sys/riscv/riscv/plic.c
===================================================================
--- sys/riscv/riscv/plic.c
+++ sys/riscv/riscv/plic.c
@@ -53,10 +53,17 @@
 #include "pic_if.h"
 
 #define	PLIC_MAX_IRQS		1024
+
+/* Convert a RISC-V hart to supervisor-mode context. */
+#define	HART_TO_CONTEXT_S(h)	(2 * (h) + 1)
+
 #define	PLIC_PRIORITY(n)	(0x000000 + (n) * 0x4)
-#define	PLIC_ENABLE(n, h)	(0x002000 + (h) * 0x80 + 4 * ((n) / 32))
-#define	PLIC_THRESHOLD(h)	(0x200000 + (h) * 0x1000 + 0x0)
-#define	PLIC_CLAIM(h)		(0x200000 + (h) * 0x1000 + 0x4)
+#define	PLIC_ENABLE(n, h)						\
+    (0x002000 + HART_TO_CONTEXT_S(h) * 0x80 + 4 * ((n) / 32))
+#define	PLIC_THRESHOLD(h)						\
+    (0x200000 + HART_TO_CONTEXT_S(h) * 0x1000 + 0x0)
+#define	PLIC_CLAIM(h)							\
+    (0x200000 + HART_TO_CONTEXT_S(h) * 0x1000 + 0x4)
 
 struct plic_irqsrc {
 	struct intr_irqsrc	isrc;