diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/powercap/dtpm_cpu.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/powercap/dtpm_cpu.c')
-rw-r--r-- | drivers/powercap/dtpm_cpu.c | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/drivers/powercap/dtpm_cpu.c b/drivers/powercap/dtpm_cpu.c new file mode 100644 index 000000000..9193c3b8e --- /dev/null +++ b/drivers/powercap/dtpm_cpu.c @@ -0,0 +1,302 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2020 Linaro Limited + * + * Author: Daniel Lezcano <daniel.lezcano@linaro.org> + * + * The DTPM CPU is based on the energy model. It hooks the CPU in the + * DTPM tree which in turns update the power number by propagating the + * power number from the CPU energy model information to the parents. + * + * The association between the power and the performance state, allows + * to set the power of the CPU at the OPP granularity. + * + * The CPU hotplug is supported and the power numbers will be updated + * if a CPU is hot plugged / unplugged. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/cpumask.h> +#include <linux/cpufreq.h> +#include <linux/cpuhotplug.h> +#include <linux/dtpm.h> +#include <linux/energy_model.h> +#include <linux/of.h> +#include <linux/pm_qos.h> +#include <linux/slab.h> + +struct dtpm_cpu { + struct dtpm dtpm; + struct freq_qos_request qos_req; + int cpu; +}; + +static DEFINE_PER_CPU(struct dtpm_cpu *, dtpm_per_cpu); + +static struct dtpm_cpu *to_dtpm_cpu(struct dtpm *dtpm) +{ + return container_of(dtpm, struct dtpm_cpu, dtpm); +} + +static u64 set_pd_power_limit(struct dtpm *dtpm, u64 power_limit) +{ + struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); + struct em_perf_domain *pd = em_cpu_get(dtpm_cpu->cpu); + struct cpumask cpus; + unsigned long freq; + u64 power; + int i, nr_cpus; + + cpumask_and(&cpus, cpu_online_mask, to_cpumask(pd->cpus)); + nr_cpus = cpumask_weight(&cpus); + + for (i = 0; i < pd->nr_perf_states; i++) { + + power = pd->table[i].power * nr_cpus; + + if (power > power_limit) + break; + } + + freq = pd->table[i - 1].frequency; + + freq_qos_update_request(&dtpm_cpu->qos_req, freq); + + power_limit = pd->table[i - 1].power * nr_cpus; + + return power_limit; +} + +static u64 scale_pd_power_uw(struct cpumask *pd_mask, u64 power) +{ + unsigned long max, sum_util = 0; + int cpu; + + /* + * The capacity is the same for all CPUs belonging to + * the same perf domain. + */ + max = arch_scale_cpu_capacity(cpumask_first(pd_mask)); + + for_each_cpu_and(cpu, pd_mask, cpu_online_mask) + sum_util += sched_cpu_util(cpu); + + return (power * ((sum_util << 10) / max)) >> 10; +} + +static u64 get_pd_power_uw(struct dtpm *dtpm) +{ + struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); + struct em_perf_domain *pd; + struct cpumask *pd_mask; + unsigned long freq; + int i; + + pd = em_cpu_get(dtpm_cpu->cpu); + + pd_mask = em_span_cpus(pd); + + freq = cpufreq_quick_get(dtpm_cpu->cpu); + + for (i = 0; i < pd->nr_perf_states; i++) { + + if (pd->table[i].frequency < freq) + continue; + + return scale_pd_power_uw(pd_mask, pd->table[i].power); + } + + return 0; +} + +static int update_pd_power_uw(struct dtpm *dtpm) +{ + struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); + struct em_perf_domain *em = em_cpu_get(dtpm_cpu->cpu); + struct cpumask cpus; + int nr_cpus; + + cpumask_and(&cpus, cpu_online_mask, to_cpumask(em->cpus)); + nr_cpus = cpumask_weight(&cpus); + + dtpm->power_min = em->table[0].power; + dtpm->power_min *= nr_cpus; + + dtpm->power_max = em->table[em->nr_perf_states - 1].power; + dtpm->power_max *= nr_cpus; + + return 0; +} + +static void pd_release(struct dtpm *dtpm) +{ + struct dtpm_cpu *dtpm_cpu = to_dtpm_cpu(dtpm); + struct cpufreq_policy *policy; + + if (freq_qos_request_active(&dtpm_cpu->qos_req)) + freq_qos_remove_request(&dtpm_cpu->qos_req); + + policy = cpufreq_cpu_get(dtpm_cpu->cpu); + if (policy) { + for_each_cpu(dtpm_cpu->cpu, policy->related_cpus) + per_cpu(dtpm_per_cpu, dtpm_cpu->cpu) = NULL; + + cpufreq_cpu_put(policy); + } + + kfree(dtpm_cpu); +} + +static struct dtpm_ops dtpm_ops = { + .set_power_uw = set_pd_power_limit, + .get_power_uw = get_pd_power_uw, + .update_power_uw = update_pd_power_uw, + .release = pd_release, +}; + +static int cpuhp_dtpm_cpu_offline(unsigned int cpu) +{ + struct dtpm_cpu *dtpm_cpu; + + dtpm_cpu = per_cpu(dtpm_per_cpu, cpu); + if (dtpm_cpu) + dtpm_update_power(&dtpm_cpu->dtpm); + + return 0; +} + +static int cpuhp_dtpm_cpu_online(unsigned int cpu) +{ + struct dtpm_cpu *dtpm_cpu; + + dtpm_cpu = per_cpu(dtpm_per_cpu, cpu); + if (dtpm_cpu) + return dtpm_update_power(&dtpm_cpu->dtpm); + + return 0; +} + +static int __dtpm_cpu_setup(int cpu, struct dtpm *parent) +{ + struct dtpm_cpu *dtpm_cpu; + struct cpufreq_policy *policy; + struct em_perf_domain *pd; + char name[CPUFREQ_NAME_LEN]; + int ret = -ENOMEM; + + dtpm_cpu = per_cpu(dtpm_per_cpu, cpu); + if (dtpm_cpu) + return 0; + + policy = cpufreq_cpu_get(cpu); + if (!policy) + return 0; + + pd = em_cpu_get(cpu); + if (!pd || em_is_artificial(pd)) { + ret = -EINVAL; + goto release_policy; + } + + dtpm_cpu = kzalloc(sizeof(*dtpm_cpu), GFP_KERNEL); + if (!dtpm_cpu) { + ret = -ENOMEM; + goto release_policy; + } + + dtpm_init(&dtpm_cpu->dtpm, &dtpm_ops); + dtpm_cpu->cpu = cpu; + + for_each_cpu(cpu, policy->related_cpus) + per_cpu(dtpm_per_cpu, cpu) = dtpm_cpu; + + snprintf(name, sizeof(name), "cpu%d-cpufreq", dtpm_cpu->cpu); + + ret = dtpm_register(name, &dtpm_cpu->dtpm, parent); + if (ret) + goto out_kfree_dtpm_cpu; + + ret = freq_qos_add_request(&policy->constraints, + &dtpm_cpu->qos_req, FREQ_QOS_MAX, + pd->table[pd->nr_perf_states - 1].frequency); + if (ret) + goto out_dtpm_unregister; + + cpufreq_cpu_put(policy); + return 0; + +out_dtpm_unregister: + dtpm_unregister(&dtpm_cpu->dtpm); + dtpm_cpu = NULL; + +out_kfree_dtpm_cpu: + for_each_cpu(cpu, policy->related_cpus) + per_cpu(dtpm_per_cpu, cpu) = NULL; + kfree(dtpm_cpu); + +release_policy: + cpufreq_cpu_put(policy); + return ret; +} + +static int dtpm_cpu_setup(struct dtpm *dtpm, struct device_node *np) +{ + int cpu; + + cpu = of_cpu_node_to_id(np); + if (cpu < 0) + return 0; + + return __dtpm_cpu_setup(cpu, dtpm); +} + +static int dtpm_cpu_init(void) +{ + int ret; + + /* + * The callbacks at CPU hotplug time are calling + * dtpm_update_power() which in turns calls update_pd_power(). + * + * The function update_pd_power() uses the online mask to + * figure out the power consumption limits. + * + * At CPUHP_AP_ONLINE_DYN, the CPU is present in the CPU + * online mask when the cpuhp_dtpm_cpu_online function is + * called, but the CPU is still in the online mask for the + * tear down callback. So the power can not be updated when + * the CPU is unplugged. + * + * At CPUHP_AP_DTPM_CPU_DEAD, the situation is the opposite as + * above. The CPU online mask is not up to date when the CPU + * is plugged in. + * + * For this reason, we need to call the online and offline + * callbacks at different moments when the CPU online mask is + * consistent with the power numbers we want to update. + */ + ret = cpuhp_setup_state(CPUHP_AP_DTPM_CPU_DEAD, "dtpm_cpu:offline", + NULL, cpuhp_dtpm_cpu_offline); + if (ret < 0) + return ret; + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "dtpm_cpu:online", + cpuhp_dtpm_cpu_online, NULL); + if (ret < 0) + return ret; + + return 0; +} + +static void dtpm_cpu_exit(void) +{ + cpuhp_remove_state_nocalls(CPUHP_AP_ONLINE_DYN); + cpuhp_remove_state_nocalls(CPUHP_AP_DTPM_CPU_DEAD); +} + +struct dtpm_subsys_ops dtpm_cpu_ops = { + .name = KBUILD_MODNAME, + .init = dtpm_cpu_init, + .exit = dtpm_cpu_exit, + .setup = dtpm_cpu_setup, +}; |