diff --git a/include/grub/cs5536.h b/include/grub/cs5536.h
index de0d6df7e..90a39df44 100644
--- a/include/grub/cs5536.h
+++ b/include/grub/cs5536.h
@@ -80,6 +80,8 @@
 #define GRUB_CS5536_DIVIL_LPC_INTERRUPTS 0x1002
 #define GRUB_CS5536_MSR_DIVIL_LPC_SERIAL_IRQ_CONTROL 0x8000004e
 #define GRUB_CS5536_MSR_DIVIL_LPC_SERIAL_IRQ_CONTROL_ENABLE 0x80
+#define GRUB_CS5536_MSR_DIVIL_UART1_CONF 0x8000003a
+#define GRUB_CS5536_MSR_DIVIL_UART2_CONF 0x8000003e
 
 #define GRUB_CS5536_MSR_USB_OHCI_BASE 0x40000008
 #define GRUB_CS5536_MSR_USB_EHCI_BASE 0x40000009