--- zzzz-none-000/linux-3.10.107/drivers/cpufreq/arm_big_little.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/cpufreq/arm_big_little.c 2021-02-04 17:41:59.000000000 +0000 @@ -24,8 +24,10 @@ #include #include #include +#include +#include #include -#include +#include #include #include #include @@ -33,103 +35,329 @@ #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 +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 cpufreq_arm_bL_ops *arm_bL_ops; static struct clk *clk[MAX_CLUSTERS]; -static struct cpufreq_frequency_table *freq_table[MAX_CLUSTERS]; -static atomic_t cluster_usage[MAX_CLUSTERS] = {ATOMIC_INIT(0), ATOMIC_INIT(0)}; +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 unsigned int bL_cpufreq_get(unsigned int cpu) +static inline int raw_cpu_to_cluster(int cpu) { - u32 cur_cluster = cpu_to_cluster(cpu); + return topology_physical_package_id(cpu); +} - return clk_get_rate(clk[cur_cluster]) / 1000; +static inline int cpu_to_cluster(int cpu) +{ + return is_bL_switching_enabled() ? + MAX_CLUSTERS : raw_cpu_to_cluster(cpu); } -/* Validate policy frequency range */ -static int bL_cpufreq_verify_policy(struct cpufreq_policy *policy) +static unsigned int find_cluster_maxfreq(int cluster) { - u32 cur_cluster = cpu_to_cluster(policy->cpu); + 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; + } - return cpufreq_frequency_table_verify(policy, freq_table[cur_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 target_freq, unsigned int relation) + unsigned int index) { - struct cpufreq_freqs freqs; - u32 cpu = policy->cpu, freq_tab_idx, cur_cluster; - int ret = 0; + u32 cpu = policy->cpu, cur_cluster, new_cluster, actual_cluster; + unsigned int freqs_new; - cur_cluster = cpu_to_cluster(policy->cpu); + cur_cluster = cpu_to_cluster(cpu); + new_cluster = actual_cluster = per_cpu(physical_cluster, cpu); - freqs.old = bL_cpufreq_get(policy->cpu); + freqs_new = freq_table[cur_cluster][index].frequency; - /* Determine valid target frequency using freq_table */ - cpufreq_frequency_table_target(policy, freq_table[cur_cluster], - target_freq, relation, &freq_tab_idx); - freqs.new = freq_table[cur_cluster][freq_tab_idx].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; + } + } - pr_debug("%s: cpu: %d, cluster: %d, oldfreq: %d, target freq: %d, new freq: %d\n", - __func__, cpu, cur_cluster, freqs.old, target_freq, - freqs.new); + return bL_cpufreq_set_rate(cpu, actual_cluster, new_cluster, freqs_new); +} - if (freqs.old == freqs.new) - return 0; +static inline u32 get_table_count(struct cpufreq_frequency_table *table) +{ + int count; - cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE); + for (count = 0; table[count].frequency != CPUFREQ_TABLE_END; count++) + ; - ret = clk_set_rate(clk[cur_cluster], freqs.new * 1000); - if (ret) { - pr_err("clk_set_rate failed: %d\n", ret); - return ret; + 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 = kzalloc(sizeof(*table) * count, 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++; + } } - policy->cur = freqs.new; + table[k].driver_data = k; + table[k].frequency = CPUFREQ_TABLE_END; - cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE); + pr_debug("%s: End, table: %p, count: %d\n", __func__, table, k); - return ret; + return 0; +} + +static void _put_cluster_clk_and_freq_table(struct device *cpu_dev) +{ + 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(cpu_dev); + dev_dbg(cpu_dev, "%s: cluster: %d\n", __func__, cluster); } static void put_cluster_clk_and_freq_table(struct device *cpu_dev) { u32 cluster = cpu_to_cluster(cpu_dev->id); + int i; + + if (atomic_dec_return(&cluster_usage[cluster])) + return; - if (!atomic_dec_return(&cluster_usage[cluster])) { - clk_put(clk[cluster]); - opp_free_cpufreq_table(cpu_dev, &freq_table[cluster]); - dev_dbg(cpu_dev, "%s: cluster: %d\n", __func__, cluster); + if (cluster < MAX_CLUSTERS) + return _put_cluster_clk_and_freq_table(cpu_dev); + + 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); } + + /* free virtual table */ + kfree(freq_table[cluster]); } -static int get_cluster_clk_and_freq_table(struct device *cpu_dev) +static int _get_cluster_clk_and_freq_table(struct device *cpu_dev) { - u32 cluster = cpu_to_cluster(cpu_dev->id); - char name[14] = "cpu-cluster."; + u32 cluster = raw_cpu_to_cluster(cpu_dev->id); int ret; - if (atomic_inc_return(&cluster_usage[cluster]) != 1) + if (freq_table[cluster]) return 0; ret = arm_bL_ops->init_opp_table(cpu_dev); if (ret) { dev_err(cpu_dev, "%s: init_opp_table failed, cpu: %d, err: %d\n", __func__, cpu_dev->id, ret); - goto atomic_dec; + goto out; } - ret = opp_init_cpufreq_table(cpu_dev, &freq_table[cluster]); + 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 atomic_dec; + goto free_opp_table; } - name[12] = cluster + '0'; - clk[cluster] = clk_get_sys(name, NULL); + 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], @@ -140,15 +368,77 @@ 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]); - opp_free_cpufreq_table(cpu_dev, &freq_table[cluster]); + dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table[cluster]); -atomic_dec: - atomic_dec(&cluster_usage[cluster]); +free_opp_table: + if (arm_bL_ops->free_opp_table) + arm_bL_ops->free_opp_table(cpu_dev); +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) +{ + 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); + 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); + 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); + } + + atomic_dec(&cluster_usage[cluster]); + + return ret; +} + /* Per-CPU initialization */ static int bL_cpufreq_init(struct cpufreq_policy *policy) { @@ -167,7 +457,7 @@ if (ret) return ret; - ret = cpufreq_frequency_table_cpuinfo(policy, freq_table[cur_cluster]); + ret = cpufreq_table_validate_and_show(policy, freq_table[cur_cluster]); if (ret) { dev_err(cpu_dev, "CPU %d, cluster: %d invalid freq table\n", policy->cpu, cur_cluster); @@ -175,7 +465,17 @@ return ret; } - cpufreq_frequency_table_get_attr(freq_table[cur_cluster], policy->cpu); + 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; + } if (arm_bL_ops->get_transition_latency) policy->cpuinfo.transition_latency = @@ -183,9 +483,8 @@ else policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL; - policy->cur = bL_cpufreq_get(policy->cpu); - - cpumask_copy(policy->cpus, topology_core_cpumask(policy->cpu)); + 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; @@ -208,27 +507,69 @@ return 0; } -/* Export freq_table to sysfs */ -static struct freq_attr *bL_cpufreq_attr[] = { - &cpufreq_freq_attr_scaling_available_freqs, - NULL, -}; - static struct cpufreq_driver bL_cpufreq_driver = { .name = "arm-big-little", - .flags = CPUFREQ_STICKY, - .verify = bL_cpufreq_verify_policy, - .target = bL_cpufreq_set_target, - .get = bL_cpufreq_get, + .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, - .have_governor_per_policy = true, - .attr = bL_cpufreq_attr, + .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(struct cpufreq_arm_bL_ops *ops) { - int ret; + int ret, i; if (arm_bL_ops) { pr_debug("%s: Already registered: %s, exiting\n", __func__, @@ -243,16 +584,28 @@ 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 { - pr_info("%s: Registered platform driver: %s\n", __func__, - ops->name); + 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); @@ -265,9 +618,16 @@ 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 "); +MODULE_DESCRIPTION("Generic ARM big LITTLE cpufreq driver"); +MODULE_LICENSE("GPL v2");