diff options
Diffstat (limited to 'drivers/cpufreq/arm_big_little.c')
| -rw-r--r-- | drivers/cpufreq/arm_big_little.c | 658 |
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"); |