1 files changed, 494 insertions, 0 deletions

diff --git a/drivers/cpufreq/qcom-cpufreq.c b/drivers/cpufreq/qcom-cpufreq.c
new file mode 100644
index 000000000000..2aa7b783f276
--- /dev/null
+++ b/drivers/cpufreq/qcom-cpufreq.c
@@ -0,0 +1,494 @@
+/* drivers/cpufreq/qcom-cpufreq.c
+ *
+ * MSM architecture cpufreq driver
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (c) 2007-2016, The Linux Foundation. All rights reserved.
+ * Author: Mike A. Chan <mikechan@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/cpufreq.h>
+#include <linux/cpu.h>
+#include <linux/cpumask.h>
+#include <linux/suspend.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <trace/events/power.h>
+
+static DEFINE_MUTEX(l2bw_lock);
+
+static struct clk *cpu_clk[NR_CPUS];
+static struct clk *l2_clk;
+static DEFINE_PER_CPU(struct cpufreq_frequency_table *, freq_table);
+static bool hotplug_ready;
+
+struct cpufreq_suspend_t {
+	struct mutex suspend_mutex;
+	int device_suspended;
+};
+
+static DEFINE_PER_CPU(struct cpufreq_suspend_t, suspend_data);
+
+static int set_cpu_freq(struct cpufreq_policy *policy, unsigned int new_freq,
+			unsigned int index)
+{
+	int ret = 0;
+	struct cpufreq_freqs freqs;
+	unsigned long rate;
+
+	freqs.old = policy->cur;
+	freqs.new = new_freq;
+	freqs.cpu = policy->cpu;
+
+	trace_cpu_frequency_switch_start(freqs.old, freqs.new, policy->cpu);
+	cpufreq_freq_transition_begin(policy, &freqs);
+
+	rate = new_freq * 1000;
+	rate = clk_round_rate(cpu_clk[policy->cpu], rate);
+	ret = clk_set_rate(cpu_clk[policy->cpu], rate);
+	cpufreq_freq_transition_end(policy, &freqs, ret);
+	if (!ret)
+		trace_cpu_frequency_switch_end(policy->cpu);
+
+	return ret;
+}
+
+static int msm_cpufreq_target(struct cpufreq_policy *policy,
+				unsigned int target_freq,
+				unsigned int relation)
+{
+	int ret = 0;
+	int index;
+	struct cpufreq_frequency_table *table;
+
+	mutex_lock(&per_cpu(suspend_data, policy->cpu).suspend_mutex);
+
+	if (target_freq == policy->cur)
+		goto done;
+
+	if (per_cpu(suspend_data, policy->cpu).device_suspended) {
+		pr_debug("cpufreq: cpu%d scheduling frequency change "
+				"in suspend.\n", policy->cpu);
+		ret = -EFAULT;
+		goto done;
+	}
+
+	table = cpufreq_frequency_get_table(policy->cpu);
+	if (!table) {
+		pr_err("cpufreq: Failed to get frequency table for CPU%u\n",
+		       policy->cpu);
+		ret = -ENODEV;
+		goto done;
+	}
+	if (cpufreq_frequency_table_target(policy, table, target_freq, relation,
+			&index)) {
+		pr_err("cpufreq: invalid target_freq: %d\n", target_freq);
+		ret = -EINVAL;
+		goto done;
+	}
+
+	pr_debug("CPU[%d] target %d relation %d (%d-%d) selected %d\n",
+		policy->cpu, target_freq, relation,
+		policy->min, policy->max, table[index].frequency);
+
+	ret = set_cpu_freq(policy, table[index].frequency,
+			   table[index].driver_data);
+done:
+	mutex_unlock(&per_cpu(suspend_data, policy->cpu).suspend_mutex);
+	return ret;
+}
+
+static int msm_cpufreq_verify(struct cpufreq_policy *policy)
+{
+	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
+			policy->cpuinfo.max_freq);
+	return 0;
+}
+
+static unsigned int msm_cpufreq_get_freq(unsigned int cpu)
+{
+	return clk_get_rate(cpu_clk[cpu]) / 1000;
+}
+
+static int msm_cpufreq_init(struct cpufreq_policy *policy)
+{
+	int cur_freq;
+	int index;
+	int ret = 0;
+	struct cpufreq_frequency_table *table =
+			per_cpu(freq_table, policy->cpu);
+	int cpu;
+
+	/*
+	 * In some SoC, some cores are clocked by same source, and their
+	 * frequencies can not be changed independently. Find all other
+	 * CPUs that share same clock, and mark them as controlled by
+	 * same policy.
+	 */
+	for_each_possible_cpu(cpu)
+		if (cpu_clk[cpu] == cpu_clk[policy->cpu])
+			cpumask_set_cpu(cpu, policy->cpus);
+
+	ret = cpufreq_table_validate_and_show(policy, table);
+	if (ret) {
+		pr_err("cpufreq: failed to get policy min/max\n");
+		return ret;
+	}
+
+	cur_freq = clk_get_rate(cpu_clk[policy->cpu])/1000;
+
+	if (cpufreq_frequency_table_target(policy, table, cur_freq,
+	    CPUFREQ_RELATION_H, &index) &&
+	    cpufreq_frequency_table_target(policy, table, cur_freq,
+	    CPUFREQ_RELATION_L, &index)) {
+		pr_info("cpufreq: cpu%d at invalid freq: %d\n",
+				policy->cpu, cur_freq);
+		return -EINVAL;
+	}
+	/*
+	 * Call set_cpu_freq unconditionally so that when cpu is set to
+	 * online, frequency limit will always be updated.
+	 */
+	ret = set_cpu_freq(policy, table[index].frequency,
+			   table[index].driver_data);
+	if (ret)
+		return ret;
+	pr_debug("cpufreq: cpu%d init at %d switching to %d\n",
+			policy->cpu, cur_freq, table[index].frequency);
+	policy->cur = table[index].frequency;
+
+	return 0;
+}
+
+static int msm_cpufreq_cpu_callback(struct notifier_block *nfb,
+		unsigned long action, void *hcpu)
+{
+	unsigned int cpu = (unsigned long)hcpu;
+	int rc;
+
+	/* Fail hotplug until this driver can get CPU clocks */
+	if (!hotplug_ready)
+		return NOTIFY_BAD;
+
+	switch (action & ~CPU_TASKS_FROZEN) {
+
+	case CPU_DYING:
+		clk_disable(cpu_clk[cpu]);
+		clk_disable(l2_clk);
+		break;
+	/*
+	 * Scale down clock/power of CPU that is dead and scale it back up
+	 * before the CPU is brought up.
+	 */
+	case CPU_DEAD:
+		clk_unprepare(cpu_clk[cpu]);
+		clk_unprepare(l2_clk);
+		break;
+	case CPU_UP_CANCELED:
+		clk_unprepare(cpu_clk[cpu]);
+		clk_unprepare(l2_clk);
+		break;
+	case CPU_UP_PREPARE:
+		rc = clk_prepare(l2_clk);
+		if (rc < 0)
+			return NOTIFY_BAD;
+		rc = clk_prepare(cpu_clk[cpu]);
+		if (rc < 0) {
+			clk_unprepare(l2_clk);
+			return NOTIFY_BAD;
+		}
+		break;
+
+	case CPU_STARTING:
+		rc = clk_enable(l2_clk);
+		if (rc < 0)
+			return NOTIFY_BAD;
+		rc = clk_enable(cpu_clk[cpu]);
+		if (rc) {
+			clk_disable(l2_clk);
+			return NOTIFY_BAD;
+		}
+		break;
+
+	default:
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block __refdata msm_cpufreq_cpu_notifier = {
+	.notifier_call = msm_cpufreq_cpu_callback,
+};
+
+static int msm_cpufreq_suspend(void)
+{
+	int cpu;
+
+	for_each_possible_cpu(cpu) {
+		mutex_lock(&per_cpu(suspend_data, cpu).suspend_mutex);
+		per_cpu(suspend_data, cpu).device_suspended = 1;
+		mutex_unlock(&per_cpu(suspend_data, cpu).suspend_mutex);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int msm_cpufreq_resume(void)
+{
+	int cpu, ret;
+	struct cpufreq_policy policy;
+
+	for_each_possible_cpu(cpu) {
+		per_cpu(suspend_data, cpu).device_suspended = 0;
+	}
+
+	/*
+	 * Freq request might be rejected during suspend, resulting
+	 * in policy->cur violating min/max constraint.
+	 * Correct the frequency as soon as possible.
+	 */
+	get_online_cpus();
+	for_each_online_cpu(cpu) {
+		ret = cpufreq_get_policy(&policy, cpu);
+		if (ret)
+			continue;
+		if (policy.cur <= policy.max && policy.cur >= policy.min)
+			continue;
+		ret = cpufreq_update_policy(cpu);
+		if (ret)
+			pr_info("cpufreq: Current frequency violates policy min/max for CPU%d\n",
+			       cpu);
+		else
+			pr_info("cpufreq: Frequency violation fixed for CPU%d\n",
+				cpu);
+	}
+	put_online_cpus();
+
+	return NOTIFY_DONE;
+}
+
+static int msm_cpufreq_pm_event(struct notifier_block *this,
+				unsigned long event, void *ptr)
+{
+	switch (event) {
+	case PM_POST_HIBERNATION:
+	case PM_POST_SUSPEND:
+		return msm_cpufreq_resume();
+	case PM_HIBERNATION_PREPARE:
+	case PM_SUSPEND_PREPARE:
+		return msm_cpufreq_suspend();
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static struct notifier_block msm_cpufreq_pm_notifier = {
+	.notifier_call = msm_cpufreq_pm_event,
+};
+
+static struct freq_attr *msm_freq_attr[] = {
+	&cpufreq_freq_attr_scaling_available_freqs,
+	NULL,
+};
+
+static struct cpufreq_driver msm_cpufreq_driver = {
+	/* lps calculations are handled here. */
+	.flags		= CPUFREQ_STICKY | CPUFREQ_CONST_LOOPS,
+	.init		= msm_cpufreq_init,
+	.verify		= msm_cpufreq_verify,
+	.target		= msm_cpufreq_target,
+	.get		= msm_cpufreq_get_freq,
+	.name		= "msm",
+	.attr		= msm_freq_attr,
+};
+
+static struct cpufreq_frequency_table *cpufreq_parse_dt(struct device *dev,
+						char *tbl_name, int cpu)
+{
+	int ret, nf, i, j;
+	u32 *data;
+	struct cpufreq_frequency_table *ftbl;
+
+	/* Parse list of usable CPU frequencies. */
+	if (!of_find_property(dev->of_node, tbl_name, &nf))
+		return ERR_PTR(-EINVAL);
+	nf /= sizeof(*data);
+
+	if (nf == 0)
+		return ERR_PTR(-EINVAL);
+
+	data = devm_kzalloc(dev, nf * sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return ERR_PTR(-ENOMEM);
+
+	ret = of_property_read_u32_array(dev->of_node, tbl_name, data, nf);
+	if (ret)
+		return ERR_PTR(ret);
+
+	ftbl = devm_kzalloc(dev, (nf + 1) * sizeof(*ftbl), GFP_KERNEL);
+	if (!ftbl)
+		return ERR_PTR(-ENOMEM);
+
+	j = 0;
+	for (i = 0; i < nf; i++) {
+		unsigned long f;
+
+		f = clk_round_rate(cpu_clk[cpu], data[i] * 1000);
+		if (IS_ERR_VALUE(f))
+			break;
+		f /= 1000;
+
+		/*
+		 * Don't repeat frequencies if they round up to the same clock
+		 * frequency.
+		 *
+		 */
+		if (j > 0 && f <= ftbl[j - 1].frequency)
+			continue;
+
+		ftbl[j].driver_data = j;
+		ftbl[j].frequency = f;
+		j++;
+	}
+
+	ftbl[j].driver_data = j;
+	ftbl[j].frequency = CPUFREQ_TABLE_END;
+
+	devm_kfree(dev, data);
+
+	return ftbl;
+}
+
+static int __init msm_cpufreq_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	char clk_name[] = "cpu??_clk";
+	char tbl_name[] = "qcom,cpufreq-table-??";
+	struct clk *c;
+	int cpu;
+	struct cpufreq_frequency_table *ftbl;
+
+	l2_clk = devm_clk_get(dev, "l2_clk");
+	if (IS_ERR(l2_clk))
+		l2_clk = NULL;
+
+	for_each_possible_cpu(cpu) {
+		snprintf(clk_name, sizeof(clk_name), "cpu%d_clk", cpu);
+		c = devm_clk_get(dev, clk_name);
+		if (IS_ERR(c))
+			return PTR_ERR(c);
+		cpu_clk[cpu] = c;
+	}
+	hotplug_ready = true;
+
+	/* Use per-policy governor tunable for some targets */
+	if (of_property_read_bool(dev->of_node, "qcom,governor-per-policy"))
+		msm_cpufreq_driver.flags |= CPUFREQ_HAVE_GOVERNOR_PER_POLICY;
+
+	/* Parse commong cpufreq table for all CPUs */
+	ftbl = cpufreq_parse_dt(dev, "qcom,cpufreq-table", 0);
+	if (!IS_ERR(ftbl)) {
+		for_each_possible_cpu(cpu)
+			per_cpu(freq_table, cpu) = ftbl;
+		return 0;
+	}
+
+	/*
+	 * No common table. Parse individual tables for each unique
+	 * CPU clock.
+	 */
+	for_each_possible_cpu(cpu) {
+		snprintf(tbl_name, sizeof(tbl_name),
+			 "qcom,cpufreq-table-%d", cpu);
+		ftbl = cpufreq_parse_dt(dev, tbl_name, cpu);
+
+		/* CPU0 must contain freq table */
+		if (cpu == 0 && IS_ERR(ftbl)) {
+			dev_err(dev, "Failed to parse CPU0's freq table\n");
+			return PTR_ERR(ftbl);
+		}
+		if (cpu == 0) {
+			per_cpu(freq_table, cpu) = ftbl;
+			continue;
+		}
+
+		if (cpu_clk[cpu] != cpu_clk[cpu - 1] && IS_ERR(ftbl)) {
+			dev_err(dev, "Failed to parse CPU%d's freq table\n",
+				cpu);
+			return PTR_ERR(ftbl);
+		}
+
+		/* Use previous CPU's table if it shares same clock */
+		if (cpu_clk[cpu] == cpu_clk[cpu - 1]) {
+			if (!IS_ERR(ftbl)) {
+				dev_warn(dev, "Conflicting tables for CPU%d\n",
+					 cpu);
+				devm_kfree(dev, ftbl);
+			}
+			ftbl = per_cpu(freq_table, cpu - 1);
+		}
+		per_cpu(freq_table, cpu) = ftbl;
+	}
+
+	return 0;
+}
+
+static struct of_device_id match_table[] = {
+	{ .compatible = "qcom,msm-cpufreq" },
+	{}
+};
+
+static struct platform_driver msm_cpufreq_plat_driver = {
+	.driver = {
+		.name = "msm-cpufreq",
+		.of_match_table = match_table,
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init msm_cpufreq_register(void)
+{
+	int cpu, rc;
+
+	for_each_possible_cpu(cpu) {
+		mutex_init(&(per_cpu(suspend_data, cpu).suspend_mutex));
+		per_cpu(suspend_data, cpu).device_suspended = 0;
+	}
+
+	rc = platform_driver_probe(&msm_cpufreq_plat_driver,
+				   msm_cpufreq_probe);
+	if (rc < 0) {
+		/* Unblock hotplug if msm-cpufreq probe fails */
+		unregister_hotcpu_notifier(&msm_cpufreq_cpu_notifier);
+		for_each_possible_cpu(cpu)
+			mutex_destroy(&(per_cpu(suspend_data, cpu).
+					suspend_mutex));
+		return rc;
+	}
+
+	register_pm_notifier(&msm_cpufreq_pm_notifier);
+	return cpufreq_register_driver(&msm_cpufreq_driver);
+}
+
+subsys_initcall(msm_cpufreq_register);
+
+static int __init msm_cpufreq_early_register(void)
+{
+	return register_hotcpu_notifier(&msm_cpufreq_cpu_notifier);
+}
+core_initcall(msm_cpufreq_early_register);