diff --git a/include/ec_commands.h b/include/ec_commands.h
index 392c1f1a43..444ba61e59 100644
--- a/include/ec_commands.h
+++ b/include/ec_commands.h
@@ -71,6 +71,10 @@
 #define EC_LPC_CMDR_SCI		(1 << 5)  /* SCI event is pending */
 #define EC_LPC_CMDR_SMI		(1 << 6)  /* SMI event is pending */
 
+/* MEC uses 0x800/0x804 as register/index pair, thus an 8-byte resource */
+#define MEC_EMI_BASE		0x800
+#define MEC_EMI_SIZE		8
+
 #define EC_LPC_ADDR_MEMMAP       0x900
 #define EC_MEMMAP_SIZE         255 /* ACPI IO buffer max is 255 bytes */
 #define EC_MEMMAP_TEXT_MAX     8   /* Size of a string in the memory map */