MIPS: JZ4740: Add power-management and system reset support

Add support for suspend/resume and poweroff/reboot on a JZ4740 SoC.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1398/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/jz4740/pm.c

+/*
+ *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ *	JZ4740 SoC power management support
+ *
+ *  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.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+#include <linux/suspend.h>
+
+#include <asm/mach-jz4740/clock.h>
+
+#include "clock.h"
+#include "irq.h"
+
+static int jz4740_pm_enter(suspend_state_t state)
+{
+	jz4740_intc_suspend();
+	jz4740_clock_suspend();
+
+	jz4740_clock_set_wait_mode(JZ4740_WAIT_MODE_SLEEP);
+
+	__asm__(".set\tmips3\n\t"
+		"wait\n\t"
+		".set\tmips0");
+
+	jz4740_clock_set_wait_mode(JZ4740_WAIT_MODE_IDLE);
+
+	jz4740_clock_resume();
+	jz4740_intc_resume();
+
+	return 0;
+}
+
+static struct platform_suspend_ops jz4740_pm_ops = {
+	.valid		= suspend_valid_only_mem,
+	.enter		= jz4740_pm_enter,
+};
+
+static int __init jz4740_pm_init(void)
+{
+	suspend_set_ops(&jz4740_pm_ops);
+	return 0;
+
+}
+late_initcall(jz4740_pm_init);

arch/mips/jz4740/reset.c

+/*
+ *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ *
+ *  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.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/pm.h>
+
+#include <asm/reboot.h>
+
+#include <asm/mach-jz4740/base.h>
+#include <asm/mach-jz4740/timer.h>
+
+static void jz4740_halt(void)
+{
+	while (1) {
+		__asm__(".set push;\n"
+			".set mips3;\n"
+			"wait;\n"
+			".set pop;\n"
+		);
+	}
+}
+
+#define JZ_REG_WDT_DATA 0x00
+#define JZ_REG_WDT_COUNTER_ENABLE 0x04
+#define JZ_REG_WDT_COUNTER 0x08
+#define JZ_REG_WDT_CTRL 0x0c
+
+static void jz4740_restart(char *command)
+{
+	void __iomem *wdt_base = ioremap(JZ4740_WDT_BASE_ADDR, 0x0f);
+
+	jz4740_timer_enable_watchdog();
+
+	writeb(0, wdt_base + JZ_REG_WDT_COUNTER_ENABLE);
+
+	writew(0, wdt_base + JZ_REG_WDT_COUNTER);
+	writew(0, wdt_base + JZ_REG_WDT_DATA);
+	writew(BIT(2), wdt_base + JZ_REG_WDT_CTRL);
+
+	writeb(1, wdt_base + JZ_REG_WDT_COUNTER_ENABLE);
+	jz4740_halt();
+}
+
+#define JZ_REG_RTC_CTRL		0x00
+#define JZ_REG_RTC_HIBERNATE	0x20
+
+#define JZ_RTC_CTRL_WRDY	BIT(7)
+
+static void jz4740_power_off(void)
+{
+	void __iomem *rtc_base = ioremap(JZ4740_RTC_BASE_ADDR, 0x24);
+	uint32_t ctrl;
+
+	do {
+		ctrl = readl(rtc_base + JZ_REG_RTC_CTRL);
+	} while (!(ctrl & JZ_RTC_CTRL_WRDY));
+
+	writel(1, rtc_base + JZ_REG_RTC_HIBERNATE);
+	jz4740_halt();
+}
+
+void jz4740_reset_init(void)
+{
+	_machine_restart = jz4740_restart;
+	_machine_halt = jz4740_halt;
+	pm_power_off = jz4740_power_off;
+}

arch/mips/jz4740/reset.h

+#ifndef __MIPS_JZ4740_RESET_H__
+#define __MIPS_JZ4740_RESET_H__
+
+extern void jz4740_reset_init(void);
+
+#endif