1 files changed, 158 insertions, 0 deletions
diff --git a/arch/mips/loongson2ef/common/pm.c b/arch/mips/loongson2ef/common/pm.c
new file mode 100644
index 000000000000..11f4cfd581fb
--- /dev/null
+++ b/arch/mips/loongson2ef/common/pm.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * loongson-specific suspend support
+ *
+ *  Copyright (C) 2009 Lemote Inc.
+ *  Author: Wu Zhangjin <wuzhangjin@gmail.com>
+ */
+#include <linux/suspend.h>
+#include <linux/interrupt.h>
+#include <linux/pm.h>
+
+#include <asm/i8259.h>
+#include <asm/mipsregs.h>
+
+#include <loongson.h>
+
+static unsigned int __maybe_unused cached_master_mask;	/* i8259A */
+static unsigned int __maybe_unused cached_slave_mask;
+static unsigned int __maybe_unused cached_bonito_irq_mask; /* bonito */
+
+void arch_suspend_disable_irqs(void)
+{
+	/* disable all mips events */
+	local_irq_disable();
+
+#ifdef CONFIG_I8259
+	/* disable all events of i8259A */
+	cached_slave_mask = inb(PIC_SLAVE_IMR);
+	cached_master_mask = inb(PIC_MASTER_IMR);
+
+	outb(0xff, PIC_SLAVE_IMR);
+	inb(PIC_SLAVE_IMR);
+	outb(0xff, PIC_MASTER_IMR);
+	inb(PIC_MASTER_IMR);
+#endif
+	/* disable all events of bonito */
+	cached_bonito_irq_mask = LOONGSON_INTEN;
+	LOONGSON_INTENCLR = 0xffff;
+	(void)LOONGSON_INTENCLR;
+}
+
+void arch_suspend_enable_irqs(void)
+{
+	/* enable all mips events */
+	local_irq_enable();
+#ifdef CONFIG_I8259
+	/* only enable the cached events of i8259A */
+	outb(cached_slave_mask, PIC_SLAVE_IMR);
+	outb(cached_master_mask, PIC_MASTER_IMR);
+#endif
+	/* enable all cached events of bonito */
+	LOONGSON_INTENSET = cached_bonito_irq_mask;
+	(void)LOONGSON_INTENSET;
+}
+
+/*
+ * Setup the board-specific events for waking up loongson from wait mode
+ */
+void __weak setup_wakeup_events(void)
+{
+}
+
+/*
+ * Check wakeup events
+ */
+int __weak wakeup_loongson(void)
+{
+	return 1;
+}
+
+/*
+ * If the events are really what we want to wakeup the CPU, wake it up
+ * otherwise put the CPU asleep again.
+ */
+static void wait_for_wakeup_events(void)
+{
+	while (!wakeup_loongson())
+		writel(readl(LOONGSON_CHIPCFG) & ~0x7, LOONGSON_CHIPCFG);
+}
+
+/*
+ * Stop all perf counters
+ *
+ * $24 is the control register of Loongson perf counter
+ */
+static inline void stop_perf_counters(void)
+{
+	__write_64bit_c0_register($24, 0, 0);
+}
+
+
+static void loongson_suspend_enter(void)
+{
+	static unsigned int cached_cpu_freq;
+
+	/* setup wakeup events via enabling the IRQs */
+	setup_wakeup_events();
+
+	stop_perf_counters();
+
+	cached_cpu_freq = readl(LOONGSON_CHIPCFG);
+
+	/* Put CPU into wait mode */
+	writel(readl(LOONGSON_CHIPCFG) & ~0x7, LOONGSON_CHIPCFG);
+
+	/* wait for the given events to wakeup cpu from wait mode */
+	wait_for_wakeup_events();
+
+	writel(cached_cpu_freq, LOONGSON_CHIPCFG);
+
+	mmiowb();
+}
+
+void __weak mach_suspend(void)
+{
+}
+
+void __weak mach_resume(void)
+{
+}
+
+static int loongson_pm_enter(suspend_state_t state)
+{
+	mach_suspend();
+
+	/* processor specific suspend */
+	loongson_suspend_enter();
+
+	mach_resume();
+
+	return 0;
+}
+
+static int loongson_pm_valid_state(suspend_state_t state)
+{
+	switch (state) {
+	case PM_SUSPEND_ON:
+	case PM_SUSPEND_STANDBY:
+	case PM_SUSPEND_MEM:
+		return 1;
+
+	default:
+		return 0;
+	}
+}
+
+static const struct platform_suspend_ops loongson_pm_ops = {
+	.valid	= loongson_pm_valid_state,
+	.enter	= loongson_pm_enter,
+};
+
+static int __init loongson_pm_init(void)
+{
+	suspend_set_ops(&loongson_pm_ops);
+
+	return 0;
+}
+arch_initcall(loongson_pm_init);