MIPS: Attach ranchu machine reset and power-off routines

If "reboot" or "reboot -p" are requested from the emulator, these
routines will be triggered which in return should reset or power-off the
machine.

In order to enable this power management device, appropriate device tree node
"goldfish_reset" is expected in the device tree to acquire device memory map
location.

This simple device contains only one register, which holds commands to be performed.
    GORESET: 0x42 command for reboot
    GOPOWEROFF: 0x43 command for shutdown

Change-Id: I151b518a3982cb6c871dedf566846fa07c9304c6
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>

arch/mips/goldfish/Makefile

@@ -10,6 +10,7 @@ obj-$(CONFIG_GOLDFISH)	+= goldfish-platform.o
 obj-$(CONFIG_GOLDFISH)	+= goldfish-interrupt.o
 obj-$(CONFIG_GOLDFISH)	+= goldfish-time.o
 obj-$(CONFIG_GOLDFISH)	+= pm.o
+obj-$(CONFIG_GOLDFISH)	+= goldfish-reset.o
 
 obj-$(CONFIG_MIPS_GOLDFISH_SWITCH)	+= switch.o
 

arch/mips/goldfish/goldfish-reset.c

+/* arch/mips/goldfish/goldfish-reset.c
+ *
+ * Goldfish Machine Reset Routines
+ *
+ * Copyright (C) 2007 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/pm.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+#include <asm/idle.h>
+#include <asm/reboot.h>
+#include <asm/mips-boards/generic.h>
+
+#define GORESET           0x42
+#define GOSHUTDOWN        0x43
+
+static struct device_node *dn;
+static uint32_t base;
+static unsigned int __iomem *softres_reg;
+
+static void mips_machine_restart(char *command)
+{
+	writel(GORESET, softres_reg);
+}
+
+static void mips_machine_halt(void)
+{
+	writel(GOSHUTDOWN, softres_reg);
+}
+
+static int __init mips_reboot_setup(void)
+{
+	if ((dn = of_find_node_by_name(NULL, "goldfish_reset")) == NULL) {
+		printk(KERN_WARNING "mips_reboot_setup() failed to "
+			"fetch device node \'goldfish_reset\'!\n");
+		return -1;
+	}
+
+	if (of_property_read_u32(dn, "reg", &base) < 0) {
+		printk(KERN_WARNING "mips_reboot_setup() failed to "
+			"fetch device base address property \'reg\'! %x\n", base);
+		return -1;
+	}
+
+	softres_reg = ioremap(base, sizeof(unsigned int));
+
+	_machine_restart = mips_machine_restart;
+	_machine_halt = mips_machine_halt;
+	pm_power_off = mips_machine_halt;
+
+	return 0;
+}
+
+arch_initcall(mips_reboot_setup);