board: Add new Broadcom Northstar board

This adds a simple Northstar "BRCMNS" board to be used with
the BCM4708x and BCM5301x chips.

The main intention is to use this with the D-Link DIR-890L
and DIR-885L routers for loading the kernel into RAM from
NAND memory using the BCH-1 ECC and using the separately
submitted SEAMA load command, so we are currently not adding
support for things such as networking.

The DTS file is a multiplatform NorthStar board, designed to
be usable with several NorthStar designs by avoiding any
particulars not related to the operation of U-Boot.

If other board need other ECC for example, they need to
create a separate DTS file and augment the code, but I don't
know if any other users will turn up.

Cc: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 60ac7d4..fdb24d6 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -2285,6 +2285,7 @@
 source "board/armltd/vexpress/Kconfig"
 source "board/armltd/vexpress64/Kconfig"
 source "board/cortina/presidio-asic/Kconfig"
+source "board/broadcom/bcmns/Kconfig"
 source "board/broadcom/bcmns3/Kconfig"
 source "board/cavium/thunderx/Kconfig"
 source "board/eets/pdu001/Kconfig"
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index 3385948..ca03a96 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -1200,6 +1200,8 @@
 	bcm2837-rpi-cm3-io3.dtb \
 	bcm2711-rpi-4-b.dtb
 
+dtb-$(CONFIG_TARGET_BCMNS) += ns-board.dtb
+
 dtb-$(CONFIG_TARGET_BCMNS3) += ns3-board.dtb
 
 dtb-$(CONFIG_ARCH_BCMSTB) += bcm7xxx.dtb
diff --git a/arch/arm/dts/ns-board.dts b/arch/arm/dts/ns-board.dts
new file mode 100644
index 0000000..bc2a0dd
--- /dev/null
+++ b/arch/arm/dts/ns-board.dts
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier:      GPL-2.0+
+
+/dts-v1/;
+
+#include "bcm5301x.dtsi"
+
+/ {
+	/*
+	 * The Northstar does not have a proper fallback compatible, but
+	 * these basic chips will suffice.
+	 */
+	model = "Northstar model";
+	compatible = "brcm,bcm47094", "brcm,bcm4708";
+	#address-cells = <1>;
+	#size-cells = <1>;
+	interrupt-parent = <&gic>;
+
+	memory {
+		device_type = "memory";
+		reg = <0x00000000 0x08000000>,
+		      <0x88000000 0x08000000>;
+	};
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	nand-controller@18028000 {
+		nandcs: nand@0 {
+			compatible = "brcm,nandcs";
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <1>;
+
+			/*
+			 * Same as using the bcm5301x-nand-cs0-bch1.dtsi
+			 * include from the Linux kernel.
+			 */
+			nand-ecc-algo = "bch";
+			nand-ecc-strength = <1>;
+			nand-ecc-step-size = <512>;
+
+			partitions {
+				compatible = "brcm,bcm947xx-cfe-partitions";
+			};
+		};
+	};
+};
+
+&uart0 {
+	clock-frequency = <125000000>;
+	status = "okay";
+};