1 files changed, 83 insertions, 0 deletions
diff --git a/arch/arm/mach-imx/cpuidle-imx6q.c b/arch/arm/mach-imx/cpuidle-imx6q.c
new file mode 100644
index 000000000..094337dc1
--- /dev/null
+++ b/arch/arm/mach-imx/cpuidle-imx6q.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/module.h>
+#include <asm/cpuidle.h>
+
+#include <soc/imx/cpuidle.h>
+
+#include "common.h"
+#include "cpuidle.h"
+#include "hardware.h"
+
+static int num_idle_cpus = 0;
+static DEFINE_RAW_SPINLOCK(cpuidle_lock);
+
+static int imx6q_enter_wait(struct cpuidle_device *dev,
+			    struct cpuidle_driver *drv, int index)
+{
+	raw_spin_lock(&cpuidle_lock);
+	if (++num_idle_cpus == num_online_cpus())
+		imx6_set_lpm(WAIT_UNCLOCKED);
+	raw_spin_unlock(&cpuidle_lock);
+
+	rcu_idle_enter();
+	cpu_do_idle();
+	rcu_idle_exit();
+
+	raw_spin_lock(&cpuidle_lock);
+	if (num_idle_cpus-- == num_online_cpus())
+		imx6_set_lpm(WAIT_CLOCKED);
+	raw_spin_unlock(&cpuidle_lock);
+
+	return index;
+}
+
+static struct cpuidle_driver imx6q_cpuidle_driver = {
+	.name = "imx6q_cpuidle",
+	.owner = THIS_MODULE,
+	.states = {
+		/* WFI */
+		ARM_CPUIDLE_WFI_STATE,
+		/* WAIT */
+		{
+			.exit_latency = 50,
+			.target_residency = 75,
+			.flags = CPUIDLE_FLAG_TIMER_STOP | CPUIDLE_FLAG_RCU_IDLE,
+			.enter = imx6q_enter_wait,
+			.name = "WAIT",
+			.desc = "Clock off",
+		},
+	},
+	.state_count = 2,
+	.safe_state_index = 0,
+};
+
+/*
+ * i.MX6 Q/DL has an erratum (ERR006687) that prevents the FEC from waking the
+ * CPUs when they are in wait(unclocked) state. As the hardware workaround isn't
+ * applicable to all boards, disable the deeper idle state when the workaround
+ * isn't present and the FEC is in use.
+ */
+void imx6q_cpuidle_fec_irqs_used(void)
+{
+	cpuidle_driver_state_disabled(&imx6q_cpuidle_driver, 1, true);
+}
+EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_used);
+
+void imx6q_cpuidle_fec_irqs_unused(void)
+{
+	cpuidle_driver_state_disabled(&imx6q_cpuidle_driver, 1, false);
+}
+EXPORT_SYMBOL_GPL(imx6q_cpuidle_fec_irqs_unused);
+
+int __init imx6q_cpuidle_init(void)
+{
+	/* Set INT_MEM_CLK_LPM bit to get a reliable WAIT mode support */
+	imx6_set_int_mem_clk_lpm(true);
+
+	return cpuidle_register(&imx6q_cpuidle_driver, NULL);
+}