Adding upstream version 4.19.249.upstream/4.19.249

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

1 files changed, 388 insertions, 0 deletions

diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
new file mode 100644
index 000000000..e58bfcb11
--- /dev/null
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -0,0 +1,388 @@
+/*
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ *
+ * Copyright (C) 2014 Linaro.
+ * Viresh Kumar <viresh.kumar@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/cpu_cooling.h>
+#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#include "cpufreq-dt.h"
+
+struct private_data {
+	struct opp_table *opp_table;
+	struct device *cpu_dev;
+	struct thermal_cooling_device *cdev;
+	const char *reg_name;
+	bool have_static_opps;
+};
+
+static struct freq_attr *cpufreq_dt_attr[] = {
+	&cpufreq_freq_attr_scaling_available_freqs,
+	NULL,   /* Extra space for boost-attr if required */
+	NULL,
+};
+
+static int set_target(struct cpufreq_policy *policy, unsigned int index)
+{
+	struct private_data *priv = policy->driver_data;
+	unsigned long freq = policy->freq_table[index].frequency;
+	int ret;
+
+	ret = dev_pm_opp_set_rate(priv->cpu_dev, freq * 1000);
+
+	if (!ret) {
+		arch_set_freq_scale(policy->related_cpus, freq,
+				    policy->cpuinfo.max_freq);
+	}
+
+	return ret;
+}
+
+/*
+ * An earlier version of opp-v1 bindings used to name the regulator
+ * "cpu0-supply", we still need to handle that for backwards compatibility.
+ */
+static const char *find_supply_name(struct device *dev)
+{
+	struct device_node *np;
+	struct property *pp;
+	int cpu = dev->id;
+	const char *name = NULL;
+
+	np = of_node_get(dev->of_node);
+
+	/* This must be valid for sure */
+	if (WARN_ON(!np))
+		return NULL;
+
+	/* Try "cpu0" for older DTs */
+	if (!cpu) {
+		pp = of_find_property(np, "cpu0-supply", NULL);
+		if (pp) {
+			name = "cpu0";
+			goto node_put;
+		}
+	}
+
+	pp = of_find_property(np, "cpu-supply", NULL);
+	if (pp) {
+		name = "cpu";
+		goto node_put;
+	}
+
+	dev_dbg(dev, "no regulator for cpu%d\n", cpu);
+node_put:
+	of_node_put(np);
+	return name;
+}
+
+static int resources_available(void)
+{
+	struct device *cpu_dev;
+	struct regulator *cpu_reg;
+	struct clk *cpu_clk;
+	int ret = 0;
+	const char *name;
+
+	cpu_dev = get_cpu_device(0);
+	if (!cpu_dev) {
+		pr_err("failed to get cpu0 device\n");
+		return -ENODEV;
+	}
+
+	cpu_clk = clk_get(cpu_dev, NULL);
+	ret = PTR_ERR_OR_ZERO(cpu_clk);
+	if (ret) {
+		/*
+		 * If cpu's clk node is present, but clock is not yet
+		 * registered, we should try defering probe.
+		 */
+		if (ret == -EPROBE_DEFER)
+			dev_dbg(cpu_dev, "clock not ready, retry\n");
+		else
+			dev_err(cpu_dev, "failed to get clock: %d\n", ret);
+
+		return ret;
+	}
+
+	clk_put(cpu_clk);
+
+	name = find_supply_name(cpu_dev);
+	/* Platform doesn't require regulator */
+	if (!name)
+		return 0;
+
+	cpu_reg = regulator_get_optional(cpu_dev, name);
+	ret = PTR_ERR_OR_ZERO(cpu_reg);
+	if (ret) {
+		/*
+		 * If cpu's regulator supply node is present, but regulator is
+		 * not yet registered, we should try defering probe.
+		 */
+		if (ret == -EPROBE_DEFER)
+			dev_dbg(cpu_dev, "cpu0 regulator not ready, retry\n");
+		else
+			dev_dbg(cpu_dev, "no regulator for cpu0: %d\n", ret);
+
+		return ret;
+	}
+
+	regulator_put(cpu_reg);
+	return 0;
+}
+
+static int cpufreq_init(struct cpufreq_policy *policy)
+{
+	struct cpufreq_frequency_table *freq_table;
+	struct opp_table *opp_table = NULL;
+	struct private_data *priv;
+	struct device *cpu_dev;
+	struct clk *cpu_clk;
+	unsigned int transition_latency;
+	bool fallback = false;
+	const char *name;
+	int ret;
+
+	cpu_dev = get_cpu_device(policy->cpu);
+	if (!cpu_dev) {
+		pr_err("failed to get cpu%d device\n", policy->cpu);
+		return -ENODEV;
+	}
+
+	cpu_clk = clk_get(cpu_dev, NULL);
+	if (IS_ERR(cpu_clk)) {
+		ret = PTR_ERR(cpu_clk);
+		dev_err(cpu_dev, "%s: failed to get clk: %d\n", __func__, ret);
+		return ret;
+	}
+
+	/* Get OPP-sharing information from "operating-points-v2" bindings */
+	ret = dev_pm_opp_of_get_sharing_cpus(cpu_dev, policy->cpus);
+	if (ret) {
+		if (ret != -ENOENT)
+			goto out_put_clk;
+
+		/*
+		 * operating-points-v2 not supported, fallback to old method of
+		 * finding shared-OPPs for backward compatibility if the
+		 * platform hasn't set sharing CPUs.
+		 */
+		if (dev_pm_opp_get_sharing_cpus(cpu_dev, policy->cpus))
+			fallback = true;
+	}
+
+	/*
+	 * OPP layer will be taking care of regulators now, but it needs to know
+	 * the name of the regulator first.
+	 */
+	name = find_supply_name(cpu_dev);
+	if (name) {
+		opp_table = dev_pm_opp_set_regulators(cpu_dev, &name, 1);
+		if (IS_ERR(opp_table)) {
+			ret = PTR_ERR(opp_table);
+			dev_err(cpu_dev, "Failed to set regulator for cpu%d: %d\n",
+				policy->cpu, ret);
+			goto out_put_clk;
+		}
+	}
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		ret = -ENOMEM;
+		goto out_put_regulator;
+	}
+
+	priv->reg_name = name;
+	priv->opp_table = opp_table;
+
+	/*
+	 * Initialize OPP tables for all policy->cpus. They will be shared by
+	 * all CPUs which have marked their CPUs shared with OPP bindings.
+	 *
+	 * For platforms not using operating-points-v2 bindings, we do this
+	 * before updating policy->cpus. Otherwise, we will end up creating
+	 * duplicate OPPs for policy->cpus.
+	 *
+	 * OPPs might be populated at runtime, don't check for error here
+	 */
+	if (!dev_pm_opp_of_cpumask_add_table(policy->cpus))
+		priv->have_static_opps = true;
+
+	/*
+	 * But we need OPP table to function so if it is not there let's
+	 * give platform code chance to provide it for us.
+	 */
+	ret = dev_pm_opp_get_opp_count(cpu_dev);
+	if (ret <= 0) {
+		dev_dbg(cpu_dev, "OPP table is not ready, deferring probe\n");
+		ret = -EPROBE_DEFER;
+		goto out_free_opp;
+	}
+
+	if (fallback) {
+		cpumask_setall(policy->cpus);
+
+		/*
+		 * OPP tables are initialized only for policy->cpu, do it for
+		 * others as well.
+		 */
+		ret = dev_pm_opp_set_sharing_cpus(cpu_dev, policy->cpus);
+		if (ret)
+			dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
+				__func__, ret);
+	}
+
+	ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
+	if (ret) {
+		dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret);
+		goto out_free_opp;
+	}
+
+	priv->cpu_dev = cpu_dev;
+	policy->driver_data = priv;
+	policy->clk = cpu_clk;
+	policy->freq_table = freq_table;
+
+	policy->suspend_freq = dev_pm_opp_get_suspend_opp_freq(cpu_dev) / 1000;
+
+	/* Support turbo/boost mode */
+	if (policy_has_boost_freq(policy)) {
+		/* This gets disabled by core on driver unregister */
+		ret = cpufreq_enable_boost_support();
+		if (ret)
+			goto out_free_cpufreq_table;
+		cpufreq_dt_attr[1] = &cpufreq_freq_attr_scaling_boost_freqs;
+	}
+
+	transition_latency = dev_pm_opp_get_max_transition_latency(cpu_dev);
+	if (!transition_latency)
+		transition_latency = CPUFREQ_ETERNAL;
+
+	policy->cpuinfo.transition_latency = transition_latency;
+	policy->dvfs_possible_from_any_cpu = true;
+
+	return 0;
+
+out_free_cpufreq_table:
+	dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
+out_free_opp:
+	if (priv->have_static_opps)
+		dev_pm_opp_of_cpumask_remove_table(policy->cpus);
+	kfree(priv);
+out_put_regulator:
+	if (name)
+		dev_pm_opp_put_regulators(opp_table);
+out_put_clk:
+	clk_put(cpu_clk);
+
+	return ret;
+}
+
+static int cpufreq_exit(struct cpufreq_policy *policy)
+{
+	struct private_data *priv = policy->driver_data;
+
+	cpufreq_cooling_unregister(priv->cdev);
+	dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
+	if (priv->have_static_opps)
+		dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
+	if (priv->reg_name)
+		dev_pm_opp_put_regulators(priv->opp_table);
+
+	clk_put(policy->clk);
+	kfree(priv);
+
+	return 0;
+}
+
+static void cpufreq_ready(struct cpufreq_policy *policy)
+{
+	struct private_data *priv = policy->driver_data;
+
+	priv->cdev = of_cpufreq_cooling_register(policy);
+}
+
+static struct cpufreq_driver dt_cpufreq_driver = {
+	.flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
+	.verify = cpufreq_generic_frequency_table_verify,
+	.target_index = set_target,
+	.get = cpufreq_generic_get,
+	.init = cpufreq_init,
+	.exit = cpufreq_exit,
+	.ready = cpufreq_ready,
+	.name = "cpufreq-dt",
+	.attr = cpufreq_dt_attr,
+	.suspend = cpufreq_generic_suspend,
+};
+
+static int dt_cpufreq_probe(struct platform_device *pdev)
+{
+	struct cpufreq_dt_platform_data *data = dev_get_platdata(&pdev->dev);
+	int ret;
+
+	/*
+	 * All per-cluster (CPUs sharing clock/voltages) initialization is done
+	 * from ->init(). In probe(), we just need to make sure that clk and
+	 * regulators are available. Else defer probe and retry.
+	 *
+	 * FIXME: Is checking this only for CPU0 sufficient ?
+	 */
+	ret = resources_available();
+	if (ret)
+		return ret;
+
+	if (data) {
+		if (data->have_governor_per_policy)
+			dt_cpufreq_driver.flags |= CPUFREQ_HAVE_GOVERNOR_PER_POLICY;
+
+		dt_cpufreq_driver.resume = data->resume;
+		if (data->suspend)
+			dt_cpufreq_driver.suspend = data->suspend;
+	}
+
+	ret = cpufreq_register_driver(&dt_cpufreq_driver);
+	if (ret)
+		dev_err(&pdev->dev, "failed register driver: %d\n", ret);
+
+	return ret;
+}
+
+static int dt_cpufreq_remove(struct platform_device *pdev)
+{
+	cpufreq_unregister_driver(&dt_cpufreq_driver);
+	return 0;
+}
+
+static struct platform_driver dt_cpufreq_platdrv = {
+	.driver = {
+		.name	= "cpufreq-dt",
+	},
+	.probe		= dt_cpufreq_probe,
+	.remove		= dt_cpufreq_remove,
+};
+module_platform_driver(dt_cpufreq_platdrv);
+
+MODULE_ALIAS("platform:cpufreq-dt");
+MODULE_AUTHOR("Viresh Kumar <viresh.kumar@linaro.org>");
+MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
+MODULE_DESCRIPTION("Generic cpufreq driver");
+MODULE_LICENSE("GPL");