diff --git a/src/mainboard/siemens/mc_bdx1/mainboard.c b/src/mainboard/siemens/mc_bdx1/mainboard.c
index 8a5226b09f..fe35fe1c14 100644
--- a/src/mainboard/siemens/mc_bdx1/mainboard.c
+++ b/src/mainboard/siemens/mc_bdx1/mainboard.c
@@ -33,6 +33,7 @@
 #include <i210.h>
 #include <soc/pci_devs.h>
 #include <soc/irq.h>
+#include <soc/lpc.h>
 
 #define MAX_PATH_DEPTH		12
 #define MAX_NUM_MAPPINGS	10
@@ -102,6 +103,10 @@ static void mainboard_init(void *chip_info)
 	actl &= ~SCIS_MASK;
 	actl |= SCIS_IRQ10;
 	pci_write_config8(dev, ACPI_CNTL_OFFSET, actl);
+
+	/* Enable additional I/O decoding ranges on LPC for COM 3 and COM 4 */
+	pci_write_config32(dev, LPC_GEN1_DEC, 0x1C02E9);
+	pci_write_config32(dev, LPC_GEN2_DEC, 0x1C03E9);
 }
 
 static void mainboard_final(void *chip_info)
diff --git a/src/soc/intel/fsp_broadwell_de/include/soc/lpc.h b/src/soc/intel/fsp_broadwell_de/include/soc/lpc.h
index 30cb5764f2..60cdc89f51 100644
--- a/src/soc/intel/fsp_broadwell_de/include/soc/lpc.h
+++ b/src/soc/intel/fsp_broadwell_de/include/soc/lpc.h
@@ -25,6 +25,10 @@
 #define PIRQ_RCR2		0x68
 #define LPC_IO_DEC		0x80
 #define LPC_EN			0x82
+#define LPC_GEN1_DEC		0x84
+#define LPC_GEN2_DEC		0x88
+#define LPC_GEN3_DEC		0x8c
+#define LPC_GEN4_DEC		0x90
 #define GEN_PMCON_1		0xA0
 #define GEN_PMCON_2		0xA2
 #define GEN_PMCON_3		0xA4