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-rw-r--r--drivers/cpufreq/arm_big_little.c658
1 files changed, 0 insertions, 658 deletions
diff --git a/drivers/cpufreq/arm_big_little.c b/drivers/cpufreq/arm_big_little.c
deleted file mode 100644
index 7fe52fcddcf1..000000000000
--- a/drivers/cpufreq/arm_big_little.c
+++ /dev/null
@@ -1,658 +0,0 @@
-/*
- * ARM big.LITTLE Platforms CPUFreq support
- *
- * Copyright (C) 2013 ARM Ltd.
- * Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
- *
- * Copyright (C) 2013 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.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/clk.h>
-#include <linux/cpu.h>
-#include <linux/cpufreq.h>
-#include <linux/cpumask.h>
-#include <linux/cpu_cooling.h>
-#include <linux/export.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/of_platform.h>
-#include <linux/pm_opp.h>
-#include <linux/slab.h>
-#include <linux/topology.h>
-#include <linux/types.h>
-
-#include "arm_big_little.h"
-
-/* Currently we support only two clusters */
-#define A15_CLUSTER 0
-#define A7_CLUSTER 1
-#define MAX_CLUSTERS 2
-
-#ifdef CONFIG_BL_SWITCHER
-#include <asm/bL_switcher.h>
-static bool bL_switching_enabled;
-#define is_bL_switching_enabled() bL_switching_enabled
-#define set_switching_enabled(x) (bL_switching_enabled = (x))
-#else
-#define is_bL_switching_enabled() false
-#define set_switching_enabled(x) do { } while (0)
-#define bL_switch_request(...) do { } while (0)
-#define bL_switcher_put_enabled() do { } while (0)
-#define bL_switcher_get_enabled() do { } while (0)
-#endif
-
-#define ACTUAL_FREQ(cluster, freq) ((cluster == A7_CLUSTER) ? freq << 1 : freq)
-#define VIRT_FREQ(cluster, freq) ((cluster == A7_CLUSTER) ? freq >> 1 : freq)
-
-static struct thermal_cooling_device *cdev[MAX_CLUSTERS];
-static const struct cpufreq_arm_bL_ops *arm_bL_ops;
-static struct clk *clk[MAX_CLUSTERS];
-static struct cpufreq_frequency_table *freq_table[MAX_CLUSTERS + 1];
-static atomic_t cluster_usage[MAX_CLUSTERS + 1];
-
-static unsigned int clk_big_min; /* (Big) clock frequencies */
-static unsigned int clk_little_max; /* Maximum clock frequency (Little) */
-
-static DEFINE_PER_CPU(unsigned int, physical_cluster);
-static DEFINE_PER_CPU(unsigned int, cpu_last_req_freq);
-
-static struct mutex cluster_lock[MAX_CLUSTERS];
-
-static inline int raw_cpu_to_cluster(int cpu)
-{
- return topology_physical_package_id(cpu);
-}
-
-static inline int cpu_to_cluster(int cpu)
-{
- return is_bL_switching_enabled() ?
- MAX_CLUSTERS : raw_cpu_to_cluster(cpu);
-}
-
-static unsigned int find_cluster_maxfreq(int cluster)
-{
- int j;
- u32 max_freq = 0, cpu_freq;
-
- for_each_online_cpu(j) {
- cpu_freq = per_cpu(cpu_last_req_freq, j);
-
- if ((cluster == per_cpu(physical_cluster, j)) &&
- (max_freq < cpu_freq))
- max_freq = cpu_freq;
- }
-
- pr_debug("%s: cluster: %d, max freq: %d\n", __func__, cluster,
- max_freq);
-
- return max_freq;
-}
-
-static unsigned int clk_get_cpu_rate(unsigned int cpu)
-{
- u32 cur_cluster = per_cpu(physical_cluster, cpu);
- u32 rate = clk_get_rate(clk[cur_cluster]) / 1000;
-
- /* For switcher we use virtual A7 clock rates */
- if (is_bL_switching_enabled())
- rate = VIRT_FREQ(cur_cluster, rate);
-
- pr_debug("%s: cpu: %d, cluster: %d, freq: %u\n", __func__, cpu,
- cur_cluster, rate);
-
- return rate;
-}
-
-static unsigned int bL_cpufreq_get_rate(unsigned int cpu)
-{
- if (is_bL_switching_enabled()) {
- pr_debug("%s: freq: %d\n", __func__, per_cpu(cpu_last_req_freq,
- cpu));
-
- return per_cpu(cpu_last_req_freq, cpu);
- } else {
- return clk_get_cpu_rate(cpu);
- }
-}
-
-static unsigned int
-bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate)
-{
- u32 new_rate, prev_rate;
- int ret;
- bool bLs = is_bL_switching_enabled();
-
- mutex_lock(&cluster_lock[new_cluster]);
-
- if (bLs) {
- prev_rate = per_cpu(cpu_last_req_freq, cpu);
- per_cpu(cpu_last_req_freq, cpu) = rate;
- per_cpu(physical_cluster, cpu) = new_cluster;
-
- new_rate = find_cluster_maxfreq(new_cluster);
- new_rate = ACTUAL_FREQ(new_cluster, new_rate);
- } else {
- new_rate = rate;
- }
-
- pr_debug("%s: cpu: %d, old cluster: %d, new cluster: %d, freq: %d\n",
- __func__, cpu, old_cluster, new_cluster, new_rate);
-
- ret = clk_set_rate(clk[new_cluster], new_rate * 1000);
- if (!ret) {
- /*
- * FIXME: clk_set_rate hasn't returned an error here however it
- * may be that clk_change_rate failed due to hardware or
- * firmware issues and wasn't able to report that due to the
- * current design of the clk core layer. To work around this
- * problem we will read back the clock rate and check it is
- * correct. This needs to be removed once clk core is fixed.
- */
- if (clk_get_rate(clk[new_cluster]) != new_rate * 1000)
- ret = -EIO;
- }
-
- if (WARN_ON(ret)) {
- pr_err("clk_set_rate failed: %d, new cluster: %d\n", ret,
- new_cluster);
- if (bLs) {
- per_cpu(cpu_last_req_freq, cpu) = prev_rate;
- per_cpu(physical_cluster, cpu) = old_cluster;
- }
-
- mutex_unlock(&cluster_lock[new_cluster]);
-
- return ret;
- }
-
- mutex_unlock(&cluster_lock[new_cluster]);
-
- /* Recalc freq for old cluster when switching clusters */
- if (old_cluster != new_cluster) {
- pr_debug("%s: cpu: %d, old cluster: %d, new cluster: %d\n",
- __func__, cpu, old_cluster, new_cluster);
-
- /* Switch cluster */
- bL_switch_request(cpu, new_cluster);
-
- mutex_lock(&cluster_lock[old_cluster]);
-
- /* Set freq of old cluster if there are cpus left on it */
- new_rate = find_cluster_maxfreq(old_cluster);
- new_rate = ACTUAL_FREQ(old_cluster, new_rate);
-
- if (new_rate) {
- pr_debug("%s: Updating rate of old cluster: %d, to freq: %d\n",
- __func__, old_cluster, new_rate);
-
- if (clk_set_rate(clk[old_cluster], new_rate * 1000))
- pr_err("%s: clk_set_rate failed: %d, old cluster: %d\n",
- __func__, ret, old_cluster);
- }
- mutex_unlock(&cluster_lock[old_cluster]);
- }
-
- return 0;
-}
-
-/* Set clock frequency */
-static int bL_cpufreq_set_target(struct cpufreq_policy *policy,
- unsigned int index)
-{
- u32 cpu = policy->cpu, cur_cluster, new_cluster, actual_cluster;
- unsigned int freqs_new;
- int ret;
-
- cur_cluster = cpu_to_cluster(cpu);
- new_cluster = actual_cluster = per_cpu(physical_cluster, cpu);
-
- freqs_new = freq_table[cur_cluster][index].frequency;
-
- if (is_bL_switching_enabled()) {
- if ((actual_cluster == A15_CLUSTER) &&
- (freqs_new < clk_big_min)) {
- new_cluster = A7_CLUSTER;
- } else if ((actual_cluster == A7_CLUSTER) &&
- (freqs_new > clk_little_max)) {
- new_cluster = A15_CLUSTER;
- }
- }
-
- ret = bL_cpufreq_set_rate(cpu, actual_cluster, new_cluster, freqs_new);
-
- if (!ret) {
- arch_set_freq_scale(policy->related_cpus, freqs_new,
- policy->cpuinfo.max_freq);
- }
-
- return ret;
-}
-
-static inline u32 get_table_count(struct cpufreq_frequency_table *table)
-{
- int count;
-
- for (count = 0; table[count].frequency != CPUFREQ_TABLE_END; count++)
- ;
-
- return count;
-}
-
-/* get the minimum frequency in the cpufreq_frequency_table */
-static inline u32 get_table_min(struct cpufreq_frequency_table *table)
-{
- struct cpufreq_frequency_table *pos;
- uint32_t min_freq = ~0;
- cpufreq_for_each_entry(pos, table)
- if (pos->frequency < min_freq)
- min_freq = pos->frequency;
- return min_freq;
-}
-
-/* get the maximum frequency in the cpufreq_frequency_table */
-static inline u32 get_table_max(struct cpufreq_frequency_table *table)
-{
- struct cpufreq_frequency_table *pos;
- uint32_t max_freq = 0;
- cpufreq_for_each_entry(pos, table)
- if (pos->frequency > max_freq)
- max_freq = pos->frequency;
- return max_freq;
-}
-
-static int merge_cluster_tables(void)
-{
- int i, j, k = 0, count = 1;
- struct cpufreq_frequency_table *table;
-
- for (i = 0; i < MAX_CLUSTERS; i++)
- count += get_table_count(freq_table[i]);
-
- table = kcalloc(count, sizeof(*table), GFP_KERNEL);
- if (!table)
- return -ENOMEM;
-
- freq_table[MAX_CLUSTERS] = table;
-
- /* Add in reverse order to get freqs in increasing order */
- for (i = MAX_CLUSTERS - 1; i >= 0; i--) {
- for (j = 0; freq_table[i][j].frequency != CPUFREQ_TABLE_END;
- j++) {
- table[k].frequency = VIRT_FREQ(i,
- freq_table[i][j].frequency);
- pr_debug("%s: index: %d, freq: %d\n", __func__, k,
- table[k].frequency);
- k++;
- }
- }
-
- table[k].driver_data = k;
- table[k].frequency = CPUFREQ_TABLE_END;
-
- pr_debug("%s: End, table: %p, count: %d\n", __func__, table, k);
-
- return 0;
-}
-
-static void _put_cluster_clk_and_freq_table(struct device *cpu_dev,
- const struct cpumask *cpumask)
-{
- u32 cluster = raw_cpu_to_cluster(cpu_dev->id);
-
- if (!freq_table[cluster])
- return;
-
- clk_put(clk[cluster]);
- dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table[cluster]);
- if (arm_bL_ops->free_opp_table)
- arm_bL_ops->free_opp_table(cpumask);
- dev_dbg(cpu_dev, "%s: cluster: %d\n", __func__, cluster);
-}
-
-static void put_cluster_clk_and_freq_table(struct device *cpu_dev,
- const struct cpumask *cpumask)
-{
- u32 cluster = cpu_to_cluster(cpu_dev->id);
- int i;
-
- if (atomic_dec_return(&cluster_usage[cluster]))
- return;
-
- if (cluster < MAX_CLUSTERS)
- return _put_cluster_clk_and_freq_table(cpu_dev, cpumask);
-
- for_each_present_cpu(i) {
- struct device *cdev = get_cpu_device(i);
- if (!cdev) {
- pr_err("%s: failed to get cpu%d device\n", __func__, i);
- return;
- }
-
- _put_cluster_clk_and_freq_table(cdev, cpumask);
- }
-
- /* free virtual table */
- kfree(freq_table[cluster]);
-}
-
-static int _get_cluster_clk_and_freq_table(struct device *cpu_dev,
- const struct cpumask *cpumask)
-{
- u32 cluster = raw_cpu_to_cluster(cpu_dev->id);
- int ret;
-
- if (freq_table[cluster])
- return 0;
-
- ret = arm_bL_ops->init_opp_table(cpumask);
- if (ret) {
- dev_err(cpu_dev, "%s: init_opp_table failed, cpu: %d, err: %d\n",
- __func__, cpu_dev->id, ret);
- goto out;
- }
-
- ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table[cluster]);
- if (ret) {
- dev_err(cpu_dev, "%s: failed to init cpufreq table, cpu: %d, err: %d\n",
- __func__, cpu_dev->id, ret);
- goto free_opp_table;
- }
-
- clk[cluster] = clk_get(cpu_dev, NULL);
- if (!IS_ERR(clk[cluster])) {
- dev_dbg(cpu_dev, "%s: clk: %p & freq table: %p, cluster: %d\n",
- __func__, clk[cluster], freq_table[cluster],
- cluster);
- return 0;
- }
-
- dev_err(cpu_dev, "%s: Failed to get clk for cpu: %d, cluster: %d\n",
- __func__, cpu_dev->id, cluster);
- ret = PTR_ERR(clk[cluster]);
- dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table[cluster]);
-
-free_opp_table:
- if (arm_bL_ops->free_opp_table)
- arm_bL_ops->free_opp_table(cpumask);
-out:
- dev_err(cpu_dev, "%s: Failed to get data for cluster: %d\n", __func__,
- cluster);
- return ret;
-}
-
-static int get_cluster_clk_and_freq_table(struct device *cpu_dev,
- const struct cpumask *cpumask)
-{
- u32 cluster = cpu_to_cluster(cpu_dev->id);
- int i, ret;
-
- if (atomic_inc_return(&cluster_usage[cluster]) != 1)
- return 0;
-
- if (cluster < MAX_CLUSTERS) {
- ret = _get_cluster_clk_and_freq_table(cpu_dev, cpumask);
- if (ret)
- atomic_dec(&cluster_usage[cluster]);
- return ret;
- }
-
- /*
- * Get data for all clusters and fill virtual cluster with a merge of
- * both
- */
- for_each_present_cpu(i) {
- struct device *cdev = get_cpu_device(i);
- if (!cdev) {
- pr_err("%s: failed to get cpu%d device\n", __func__, i);
- return -ENODEV;
- }
-
- ret = _get_cluster_clk_and_freq_table(cdev, cpumask);
- if (ret)
- goto put_clusters;
- }
-
- ret = merge_cluster_tables();
- if (ret)
- goto put_clusters;
-
- /* Assuming 2 cluster, set clk_big_min and clk_little_max */
- clk_big_min = get_table_min(freq_table[0]);
- clk_little_max = VIRT_FREQ(1, get_table_max(freq_table[1]));
-
- pr_debug("%s: cluster: %d, clk_big_min: %d, clk_little_max: %d\n",
- __func__, cluster, clk_big_min, clk_little_max);
-
- return 0;
-
-put_clusters:
- for_each_present_cpu(i) {
- struct device *cdev = get_cpu_device(i);
- if (!cdev) {
- pr_err("%s: failed to get cpu%d device\n", __func__, i);
- return -ENODEV;
- }
-
- _put_cluster_clk_and_freq_table(cdev, cpumask);
- }
-
- atomic_dec(&cluster_usage[cluster]);
-
- return ret;
-}
-
-/* Per-CPU initialization */
-static int bL_cpufreq_init(struct cpufreq_policy *policy)
-{
- u32 cur_cluster = cpu_to_cluster(policy->cpu);
- struct device *cpu_dev;
- int ret;
-
- cpu_dev = get_cpu_device(policy->cpu);
- if (!cpu_dev) {
- pr_err("%s: failed to get cpu%d device\n", __func__,
- policy->cpu);
- return -ENODEV;
- }
-
- if (cur_cluster < MAX_CLUSTERS) {
- int cpu;
-
- cpumask_copy(policy->cpus, topology_core_cpumask(policy->cpu));
-
- for_each_cpu(cpu, policy->cpus)
- per_cpu(physical_cluster, cpu) = cur_cluster;
- } else {
- /* Assumption: during init, we are always running on A15 */
- per_cpu(physical_cluster, policy->cpu) = A15_CLUSTER;
- }
-
- ret = get_cluster_clk_and_freq_table(cpu_dev, policy->cpus);
- if (ret)
- return ret;
-
- policy->freq_table = freq_table[cur_cluster];
- policy->cpuinfo.transition_latency =
- arm_bL_ops->get_transition_latency(cpu_dev);
-
- dev_pm_opp_of_register_em(policy->cpus);
-
- if (is_bL_switching_enabled())
- per_cpu(cpu_last_req_freq, policy->cpu) = clk_get_cpu_rate(policy->cpu);
-
- dev_info(cpu_dev, "%s: CPU %d initialized\n", __func__, policy->cpu);
- return 0;
-}
-
-static int bL_cpufreq_exit(struct cpufreq_policy *policy)
-{
- struct device *cpu_dev;
- int cur_cluster = cpu_to_cluster(policy->cpu);
-
- if (cur_cluster < MAX_CLUSTERS) {
- cpufreq_cooling_unregister(cdev[cur_cluster]);
- cdev[cur_cluster] = NULL;
- }
-
- cpu_dev = get_cpu_device(policy->cpu);
- if (!cpu_dev) {
- pr_err("%s: failed to get cpu%d device\n", __func__,
- policy->cpu);
- return -ENODEV;
- }
-
- put_cluster_clk_and_freq_table(cpu_dev, policy->related_cpus);
- dev_dbg(cpu_dev, "%s: Exited, cpu: %d\n", __func__, policy->cpu);
-
- return 0;
-}
-
-static void bL_cpufreq_ready(struct cpufreq_policy *policy)
-{
- int cur_cluster = cpu_to_cluster(policy->cpu);
-
- /* Do not register a cpu_cooling device if we are in IKS mode */
- if (cur_cluster >= MAX_CLUSTERS)
- return;
-
- cdev[cur_cluster] = of_cpufreq_cooling_register(policy);
-}
-
-static struct cpufreq_driver bL_cpufreq_driver = {
- .name = "arm-big-little",
- .flags = CPUFREQ_STICKY |
- CPUFREQ_HAVE_GOVERNOR_PER_POLICY |
- CPUFREQ_NEED_INITIAL_FREQ_CHECK,
- .verify = cpufreq_generic_frequency_table_verify,
- .target_index = bL_cpufreq_set_target,
- .get = bL_cpufreq_get_rate,
- .init = bL_cpufreq_init,
- .exit = bL_cpufreq_exit,
- .ready = bL_cpufreq_ready,
- .attr = cpufreq_generic_attr,
-};
-
-#ifdef CONFIG_BL_SWITCHER
-static int bL_cpufreq_switcher_notifier(struct notifier_block *nfb,
- unsigned long action, void *_arg)
-{
- pr_debug("%s: action: %ld\n", __func__, action);
-
- switch (action) {
- case BL_NOTIFY_PRE_ENABLE:
- case BL_NOTIFY_PRE_DISABLE:
- cpufreq_unregister_driver(&bL_cpufreq_driver);
- break;
-
- case BL_NOTIFY_POST_ENABLE:
- set_switching_enabled(true);
- cpufreq_register_driver(&bL_cpufreq_driver);
- break;
-
- case BL_NOTIFY_POST_DISABLE:
- set_switching_enabled(false);
- cpufreq_register_driver(&bL_cpufreq_driver);
- break;
-
- default:
- return NOTIFY_DONE;
- }
-
- return NOTIFY_OK;
-}
-
-static struct notifier_block bL_switcher_notifier = {
- .notifier_call = bL_cpufreq_switcher_notifier,
-};
-
-static int __bLs_register_notifier(void)
-{
- return bL_switcher_register_notifier(&bL_switcher_notifier);
-}
-
-static int __bLs_unregister_notifier(void)
-{
- return bL_switcher_unregister_notifier(&bL_switcher_notifier);
-}
-#else
-static int __bLs_register_notifier(void) { return 0; }
-static int __bLs_unregister_notifier(void) { return 0; }
-#endif
-
-int bL_cpufreq_register(const struct cpufreq_arm_bL_ops *ops)
-{
- int ret, i;
-
- if (arm_bL_ops) {
- pr_debug("%s: Already registered: %s, exiting\n", __func__,
- arm_bL_ops->name);
- return -EBUSY;
- }
-
- if (!ops || !strlen(ops->name) || !ops->init_opp_table ||
- !ops->get_transition_latency) {
- pr_err("%s: Invalid arm_bL_ops, exiting\n", __func__);
- return -ENODEV;
- }
-
- arm_bL_ops = ops;
-
- set_switching_enabled(bL_switcher_get_enabled());
-
- for (i = 0; i < MAX_CLUSTERS; i++)
- mutex_init(&cluster_lock[i]);
-
- ret = cpufreq_register_driver(&bL_cpufreq_driver);
- if (ret) {
- pr_info("%s: Failed registering platform driver: %s, err: %d\n",
- __func__, ops->name, ret);
- arm_bL_ops = NULL;
- } else {
- ret = __bLs_register_notifier();
- if (ret) {
- cpufreq_unregister_driver(&bL_cpufreq_driver);
- arm_bL_ops = NULL;
- } else {
- pr_info("%s: Registered platform driver: %s\n",
- __func__, ops->name);
- }
- }
-
- bL_switcher_put_enabled();
- return ret;
-}
-EXPORT_SYMBOL_GPL(bL_cpufreq_register);
-
-void bL_cpufreq_unregister(const struct cpufreq_arm_bL_ops *ops)
-{
- if (arm_bL_ops != ops) {
- pr_err("%s: Registered with: %s, can't unregister, exiting\n",
- __func__, arm_bL_ops->name);
- return;
- }
-
- bL_switcher_get_enabled();
- __bLs_unregister_notifier();
- cpufreq_unregister_driver(&bL_cpufreq_driver);
- bL_switcher_put_enabled();
- pr_info("%s: Un-registered platform driver: %s\n", __func__,
- arm_bL_ops->name);
- arm_bL_ops = NULL;
-}
-EXPORT_SYMBOL_GPL(bL_cpufreq_unregister);
-
-MODULE_AUTHOR("Viresh Kumar <viresh.kumar@linaro.org>");
-MODULE_DESCRIPTION("Generic ARM big LITTLE cpufreq driver");
-MODULE_LICENSE("GPL v2");