diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 44f47195993241284fd2010f9a80a9bf574959d3..b713727663e26e7469484b6027d198500a11e3f6 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -1178,8 +1178,9 @@ int pnv_npu2_init(struct pci_controller *hose)
 
 	npu->nmmu_flush = of_property_read_bool(hose->dn, "ibm,nmmu-flush");
 
-	for (i = 0; !of_property_read_u64_index(hose->dn, "ibm,mmio-atsd",
-							i, &mmio_atsd); i++)
+	for (i = 0; i < ARRAY_SIZE(npu->mmio_atsd_regs) &&
+			!of_property_read_u64_index(hose->dn, "ibm,mmio-atsd",
+				i, &mmio_atsd); i++)
 		npu->mmio_atsd_regs[i] = ioremap(mmio_atsd, 32);
 
 	pr_info("NPU%d: Found %d MMIO ATSD registers", hose->global_number, i);