mips: Add LinkIt Smart 7688 support

The LinkIt Smart 7688 modules have a MT7688 SoC with 128 MiB of RAM
and 32 MiB of flash (SPI NOR).

This patch also includes 2 targets. One is the target that can be
programmed into the SPI NOR flash and a 2nd target "xxx-ram" is
added to support loading and booting via an already running U-Boot
version. This allows easy development and testing without the
need to flash the image each time.

Signed-off-by: Stefan Roese <sr@denx.de>
[fixed and regenerated defconfig files]
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/arch/mips/dts/linkit-smart-7688.dts b/arch/mips/dts/linkit-smart-7688.dts
new file mode 100644
index 00000000000..df4bf907c6b
--- /dev/null
+++ b/arch/mips/dts/linkit-smart-7688.dts
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Stefan Roese <sr@denx.de>
+ */
+
+/dts-v1/;
+
+#include "mt7628a.dtsi"
+
+/ {
+	compatible = "seeed,linkit-smart-7688", "ralink,mt7628a-soc";
+	model = "LinkIt-Smart-7688";
+
+	aliases {
+		serial0 = &uart2;
+		spi0 = &spi0;
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x0 0x08000000>;
+	};
+
+	chosen {
+		bootargs = "console=ttyS0,57600";
+		stdout-path = &uart2;
+	};
+};
+
+&uart2 {
+	status = "okay";
+	clock-frequency = <40000000>;
+};
+
+&spi0 {
+	status = "okay";
+	num-cs = <2>;
+
+	spi-flash@0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "spi-flash", "jedec,spi-nor";
+		spi-max-frequency = <25000000>;
+		reg = <0>;
+	};
+};