MIPS: Loongson 1B: Add board support

Adds basic platform devices for Loongson 1B, including serial port,
ethernet, USB, RTC and interrupt handler.

The Loongson 1B UART is compatible with NS16550A, the Loongson 1B GMAC is
built around a Synopsys IP Core.

Use normal instead of enhanced descriptors.

Thanks to Giuseppe for updating the normal descriptor in stmmac driver.
Thanks to Zhao Zhang for implementing the RTC driver.

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: wuzhangjin@gmail.com
Cc: zhzhl555@gmail.com
Cc: Kelvin Cheung <keguang.zhang@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/4133/
Patchwork: https://patchwork.linux-mips.org/patch/4134/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/loongson1/common/reset.c b/arch/mips/loongson1/common/reset.c
new file mode 100644
index 0000000..fb979a7
--- /dev/null
+++ b/arch/mips/loongson1/common/reset.c
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/io.h>
+#include <linux/pm.h>
+#include <asm/reboot.h>
+
+#include <loongson1.h>
+
+static void ls1x_restart(char *command)
+{
+	__raw_writel(0x1, LS1X_WDT_EN);
+	__raw_writel(0x5000000, LS1X_WDT_TIMER);
+	__raw_writel(0x1, LS1X_WDT_SET);
+}
+
+static void ls1x_halt(void)
+{
+	while (1) {
+		if (cpu_wait)
+			cpu_wait();
+	}
+}
+
+static void ls1x_power_off(void)
+{
+	ls1x_halt();
+}
+
+static int __init ls1x_reboot_setup(void)
+{
+	_machine_restart = ls1x_restart;
+	_machine_halt = ls1x_halt;
+	pm_power_off = ls1x_power_off;
+
+	return 0;
+}
+
+arch_initcall(ls1x_reboot_setup);