Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 110 insertions, 0 deletions

diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c
new file mode 100644
index 000000000..9fed1b829
--- /dev/null
+++ b/drivers/cpuidle/governor.c
@@ -0,0 +1,110 @@
+/*
+ * governor.c - governor support
+ *
+ * (C) 2006-2007 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
+ *               Shaohua Li <shaohua.li@intel.com>
+ *               Adam Belay <abelay@novell.com>
+ *
+ * This code is licenced under the GPL.
+ */
+
+#include <linux/cpu.h>
+#include <linux/cpuidle.h>
+#include <linux/mutex.h>
+#include <linux/pm_qos.h>
+
+#include "cpuidle.h"
+
+LIST_HEAD(cpuidle_governors);
+struct cpuidle_governor *cpuidle_curr_governor;
+
+/**
+ * __cpuidle_find_governor - finds a governor of the specified name
+ * @str: the name
+ *
+ * Must be called with cpuidle_lock acquired.
+ */
+static struct cpuidle_governor * __cpuidle_find_governor(const char *str)
+{
+	struct cpuidle_governor *gov;
+
+	list_for_each_entry(gov, &cpuidle_governors, governor_list)
+		if (!strncasecmp(str, gov->name, CPUIDLE_NAME_LEN))
+			return gov;
+
+	return NULL;
+}
+
+/**
+ * cpuidle_switch_governor - changes the governor
+ * @gov: the new target governor
+ * Must be called with cpuidle_lock acquired.
+ */
+int cpuidle_switch_governor(struct cpuidle_governor *gov)
+{
+	struct cpuidle_device *dev;
+
+	if (!gov)
+		return -EINVAL;
+
+	if (gov == cpuidle_curr_governor)
+		return 0;
+
+	cpuidle_uninstall_idle_handler();
+
+	if (cpuidle_curr_governor) {
+		list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
+			cpuidle_disable_device(dev);
+	}
+
+	cpuidle_curr_governor = gov;
+
+	if (gov) {
+		list_for_each_entry(dev, &cpuidle_detected_devices, device_list)
+			cpuidle_enable_device(dev);
+		cpuidle_install_idle_handler();
+		printk(KERN_INFO "cpuidle: using governor %s\n", gov->name);
+	}
+
+	return 0;
+}
+
+/**
+ * cpuidle_register_governor - registers a governor
+ * @gov: the governor
+ */
+int cpuidle_register_governor(struct cpuidle_governor *gov)
+{
+	int ret = -EEXIST;
+
+	if (!gov || !gov->select)
+		return -EINVAL;
+
+	if (cpuidle_disabled())
+		return -ENODEV;
+
+	mutex_lock(&cpuidle_lock);
+	if (__cpuidle_find_governor(gov->name) == NULL) {
+		ret = 0;
+		list_add_tail(&gov->governor_list, &cpuidle_governors);
+		if (!cpuidle_curr_governor ||
+		    cpuidle_curr_governor->rating < gov->rating)
+			cpuidle_switch_governor(gov);
+	}
+	mutex_unlock(&cpuidle_lock);
+
+	return ret;
+}
+
+/**
+ * cpuidle_governor_latency_req - Compute a latency constraint for CPU
+ * @cpu: Target CPU
+ */
+int cpuidle_governor_latency_req(unsigned int cpu)
+{
+	int global_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY);
+	struct device *device = get_cpu_device(cpu);
+	int device_req = dev_pm_qos_raw_read_value(device);
+
+	return device_req < global_req ? device_req : global_req;
+}