diff --git a/src/soc/intel/broadwell/pch/lpc.c b/src/soc/intel/broadwell/pch/lpc.c
index 41da81e..40cc61e 100644
--- a/src/soc/intel/broadwell/pch/lpc.c
+++ b/src/soc/intel/broadwell/pch/lpc.c
@@ -25,8 +25,6 @@
 
 static void pch_enable_ioapic(struct device *dev)
 {
-	u32 reg32;
-
 	/* Assign unique bus/dev/fn for I/O APIC */
 	pci_write_config16(dev, LPC_IBDF,
 		PCH_IOAPIC_PCI_BUS << 8 | PCH_IOAPIC_PCI_SLOT << 3);
@@ -34,13 +32,8 @@
 	set_ioapic_id(VIO_APIC_VADDR, 0x02);
 
 	/* affirm full set of redirection table entries ("write once") */
-	reg32 = io_apic_read(VIO_APIC_VADDR, 0x01);
-
-	/* PCH-LP has 39 redirection entries */
-	reg32 &= ~0x00ff0000;
-	reg32 |= 0x00270000;
-
-	io_apic_write(VIO_APIC_VADDR, 0x01, reg32);
+	/* PCH-LP has 40 redirection entries */
+	ioapic_set_max_vectors(VIO_APIC_VADDR, 40);
 }
 
 static void enable_hpet(struct device *dev)