diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 6f432d2a5cebdc388f5c7d88e1c807f4d83fc28f..97d4d04b0a80eb57346227da018b2f5cdee8ccdc 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -77,8 +77,8 @@ struct plic_handler {
 	void __iomem		*enable_base;
 	struct plic_priv	*priv;
 };
-static int plic_parent_irq;
-static bool plic_cpuhp_setup_done;
+static int plic_parent_irq __ro_after_init;
+static bool plic_cpuhp_setup_done __ro_after_init;
 static DEFINE_PER_CPU(struct plic_handler, plic_handlers);
 
 static inline void plic_toggle(struct plic_handler *handler,