diff --git a/arch/c6x/kernel/setup.c b/arch/c6x/kernel/setup.c
index 731db4b9014d..757128868d43 100644
--- a/arch/c6x/kernel/setup.c
+++ b/arch/c6x/kernel/setup.c
@@ -265,8 +265,8 @@ int __init c6x_add_memory(phys_addr_t start, unsigned long size)
  */
 notrace void __init machine_init(unsigned long dt_ptr)
 {
-	struct boot_param_header *dtb = __va(dt_ptr);
-	struct boot_param_header *fdt = (struct boot_param_header *)_fdt_start;
+	const void *dtb = __va(dt_ptr);
+	const void *fdt = _fdt_start;
 
 	/* interrupts must be masked */
 	set_creg(IER, 2);