diff --git a/target/linux/bcm53xx/image/Makefile b/target/linux/bcm53xx/image/Makefile
index b299f38949..4b61e1330b 100644
--- a/target/linux/bcm53xx/image/Makefile
+++ b/target/linux/bcm53xx/image/Makefile
@@ -95,10 +95,16 @@ define Device/netgear-r8000
   BOARD_ID := U12H315T00_NETGEAR
 endef
 
+define Device/smartrg-sr400ac
+  IMAGES := trx
+  IMAGE/trx := trx-serial
+endef
+
 TARGET_DEVICES += \
 	asus-rt-ac56u asus-rt-ac68u asus-rt-ac87u asus-rt-n18u \
-	netgear-r6250 netgear-r6300-v2 netgear-r8000 \
 	buffalo-wzr-1750dhp buffalo-wzr-600dhp2 buffalo-wzr-900dhp \
-	buffalo-wxr-1900dhp
+	buffalo-wxr-1900dhp \
+	netgear-r6250 netgear-r6300-v2 netgear-r8000 \
+	smartrg-sr400ac
 
 $(eval $(call BuildImage))
diff --git a/target/linux/bcm53xx/patches-3.18/303-ARM-BCM5310X-Enable-earlyprintk-on-tested-devices.patch b/target/linux/bcm53xx/patches-3.18/303-ARM-BCM5310X-Enable-earlyprintk-on-tested-devices.patch
index 2153452dd4..5a0e008cbb 100644
--- a/target/linux/bcm53xx/patches-3.18/303-ARM-BCM5310X-Enable-earlyprintk-on-tested-devices.patch
+++ b/target/linux/bcm53xx/patches-3.18/303-ARM-BCM5310X-Enable-earlyprintk-on-tested-devices.patch
@@ -123,4 +123,15 @@ Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
 +		bootargs = "console=ttyS0,115200 earlyprintk";
  	};
  
+ 	memory {
+--- a/arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
++++ b/arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
+@@ -16,7 +16,7 @@
+ 	model = "SmartRG SR400ac";
+ 
+ 	chosen {
+-		bootargs = "console=ttyS0,115200";
++		bootargs = "console=ttyS0,115200 earlyprintk";
+ 	};
+ 
  	memory {
diff --git a/target/linux/bcm53xx/patches-3.18/306-ARM-BCM5301X-Specify-RAM-on-devices-by-including-HIG.patch b/target/linux/bcm53xx/patches-3.18/306-ARM-BCM5301X-Specify-RAM-on-devices-by-including-HIG.patch
index f7bdf65563..af6c27d022 100644
--- a/target/linux/bcm53xx/patches-3.18/306-ARM-BCM5301X-Specify-RAM-on-devices-by-including-HIG.patch
+++ b/target/linux/bcm53xx/patches-3.18/306-ARM-BCM5301X-Specify-RAM-on-devices-by-including-HIG.patch
@@ -134,4 +134,16 @@ Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
 +		       0x88000000 0x18000000>;
  	};
  
+ 	leds {
+--- a/arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
++++ b/arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
+@@ -20,7 +20,8 @@
+ 	};
+ 
+ 	memory {
+-		reg = <0x00000000 0x08000000>;
++		reg = <0x00000000 0x08000000
++		       0x88000000 0x08000000>;
+ 	};
+ 
  	leds {
diff --git a/target/linux/bcm53xx/patches-3.18/351-ARM-BCM5301X-Enable-ChipCommon-UART-serial-console.patch b/target/linux/bcm53xx/patches-3.18/351-ARM-BCM5301X-Enable-ChipCommon-UART-serial-console.patch
index b50b5ac1a6..00e64097f9 100644
--- a/target/linux/bcm53xx/patches-3.18/351-ARM-BCM5301X-Enable-ChipCommon-UART-serial-console.patch
+++ b/target/linux/bcm53xx/patches-3.18/351-ARM-BCM5301X-Enable-ChipCommon-UART-serial-console.patch
@@ -208,3 +208,22 @@ Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  	clocks {
  		clk_periph: periph {
  			clock-frequency = <500000000>;
+--- a/arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
++++ b/arch/arm/boot/dts/bcm4708-smartrg-sr400ac.dts
+@@ -24,6 +24,16 @@
+ 		       0x88000000 0x08000000>;
+ 	};
+ 
++	chipcommonA {
++		uart0: serial@0300 {
++			status = "okay";
++		};
++
++		uart1: serial@0400 {
++			status = "okay";
++		};
++	};
++
+ 	leds {
+ 		compatible = "gpio-leds";
+