2017-05-31 16:59:28 +00:00
|
|
|
/*
|
|
|
|
* Arch specific cpu topology information
|
|
|
|
*
|
|
|
|
* Copyright (C) 2016, ARM Ltd.
|
|
|
|
* Written by: Juri Lelli, ARM Ltd.
|
|
|
|
*
|
|
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
|
|
* for more details.
|
|
|
|
*
|
|
|
|
* Released under the GPLv2 only.
|
|
|
|
* SPDX-License-Identifier: GPL-2.0
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <linux/acpi.h>
|
2017-05-31 16:59:30 +00:00
|
|
|
#include <linux/arch_topology.h>
|
2017-05-31 16:59:28 +00:00
|
|
|
#include <linux/cpu.h>
|
|
|
|
#include <linux/cpufreq.h>
|
|
|
|
#include <linux/device.h>
|
|
|
|
#include <linux/of.h>
|
|
|
|
#include <linux/slab.h>
|
|
|
|
#include <linux/string.h>
|
|
|
|
#include <linux/sched/topology.h>
|
|
|
|
|
|
|
|
static DEFINE_MUTEX(cpu_scale_mutex);
|
|
|
|
static DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
|
|
|
|
|
2017-05-31 16:59:31 +00:00
|
|
|
unsigned long topology_get_cpu_scale(struct sched_domain *sd, int cpu)
|
2017-05-31 16:59:28 +00:00
|
|
|
{
|
|
|
|
return per_cpu(cpu_scale, cpu);
|
|
|
|
}
|
|
|
|
|
2017-05-31 16:59:31 +00:00
|
|
|
void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
|
2017-05-31 16:59:28 +00:00
|
|
|
{
|
|
|
|
per_cpu(cpu_scale, cpu) = capacity;
|
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t cpu_capacity_show(struct device *dev,
|
|
|
|
struct device_attribute *attr,
|
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
struct cpu *cpu = container_of(dev, struct cpu, dev);
|
|
|
|
|
2017-06-23 09:25:30 +00:00
|
|
|
return sprintf(buf, "%lu\n", topology_get_cpu_scale(NULL, cpu->dev.id));
|
2017-05-31 16:59:28 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t cpu_capacity_store(struct device *dev,
|
|
|
|
struct device_attribute *attr,
|
|
|
|
const char *buf,
|
|
|
|
size_t count)
|
|
|
|
{
|
|
|
|
struct cpu *cpu = container_of(dev, struct cpu, dev);
|
|
|
|
int this_cpu = cpu->dev.id;
|
|
|
|
int i;
|
|
|
|
unsigned long new_capacity;
|
|
|
|
ssize_t ret;
|
|
|
|
|
|
|
|
if (!count)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
ret = kstrtoul(buf, 0, &new_capacity);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
if (new_capacity > SCHED_CAPACITY_SCALE)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
mutex_lock(&cpu_scale_mutex);
|
|
|
|
for_each_cpu(i, &cpu_topology[this_cpu].core_sibling)
|
2017-05-31 16:59:31 +00:00
|
|
|
topology_set_cpu_scale(i, new_capacity);
|
2017-05-31 16:59:28 +00:00
|
|
|
mutex_unlock(&cpu_scale_mutex);
|
|
|
|
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
static DEVICE_ATTR_RW(cpu_capacity);
|
|
|
|
|
|
|
|
static int register_cpu_capacity_sysctl(void)
|
|
|
|
{
|
|
|
|
int i;
|
|
|
|
struct device *cpu;
|
|
|
|
|
|
|
|
for_each_possible_cpu(i) {
|
|
|
|
cpu = get_cpu_device(i);
|
|
|
|
if (!cpu) {
|
|
|
|
pr_err("%s: too early to get CPU%d device!\n",
|
|
|
|
__func__, i);
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
device_create_file(cpu, &dev_attr_cpu_capacity);
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
subsys_initcall(register_cpu_capacity_sysctl);
|
|
|
|
|
|
|
|
static u32 capacity_scale;
|
|
|
|
static u32 *raw_capacity;
|
2017-05-31 16:59:29 +00:00
|
|
|
static bool cap_parsing_failed;
|
2017-05-31 16:59:28 +00:00
|
|
|
|
2017-05-31 16:59:31 +00:00
|
|
|
void topology_normalize_cpu_scale(void)
|
2017-05-31 16:59:28 +00:00
|
|
|
{
|
|
|
|
u64 capacity;
|
|
|
|
int cpu;
|
|
|
|
|
|
|
|
if (!raw_capacity || cap_parsing_failed)
|
|
|
|
return;
|
|
|
|
|
|
|
|
pr_debug("cpu_capacity: capacity_scale=%u\n", capacity_scale);
|
|
|
|
mutex_lock(&cpu_scale_mutex);
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
|
|
pr_debug("cpu_capacity: cpu=%d raw_capacity=%u\n",
|
|
|
|
cpu, raw_capacity[cpu]);
|
|
|
|
capacity = (raw_capacity[cpu] << SCHED_CAPACITY_SHIFT)
|
|
|
|
/ capacity_scale;
|
2017-05-31 16:59:31 +00:00
|
|
|
topology_set_cpu_scale(cpu, capacity);
|
2017-05-31 16:59:28 +00:00
|
|
|
pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
|
2017-05-31 16:59:31 +00:00
|
|
|
cpu, topology_get_cpu_scale(NULL, cpu));
|
2017-05-31 16:59:28 +00:00
|
|
|
}
|
|
|
|
mutex_unlock(&cpu_scale_mutex);
|
|
|
|
}
|
|
|
|
|
2017-05-31 16:59:31 +00:00
|
|
|
int __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
|
2017-05-31 16:59:28 +00:00
|
|
|
{
|
|
|
|
int ret = 1;
|
|
|
|
u32 cpu_capacity;
|
|
|
|
|
|
|
|
if (cap_parsing_failed)
|
|
|
|
return !ret;
|
|
|
|
|
2017-06-23 09:25:30 +00:00
|
|
|
ret = of_property_read_u32(cpu_node, "capacity-dmips-mhz",
|
2017-05-31 16:59:28 +00:00
|
|
|
&cpu_capacity);
|
|
|
|
if (!ret) {
|
|
|
|
if (!raw_capacity) {
|
|
|
|
raw_capacity = kcalloc(num_possible_cpus(),
|
|
|
|
sizeof(*raw_capacity),
|
|
|
|
GFP_KERNEL);
|
|
|
|
if (!raw_capacity) {
|
|
|
|
pr_err("cpu_capacity: failed to allocate memory for raw capacities\n");
|
|
|
|
cap_parsing_failed = true;
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
capacity_scale = max(cpu_capacity, capacity_scale);
|
|
|
|
raw_capacity[cpu] = cpu_capacity;
|
|
|
|
pr_debug("cpu_capacity: %s cpu_capacity=%u (raw)\n",
|
|
|
|
cpu_node->full_name, raw_capacity[cpu]);
|
|
|
|
} else {
|
|
|
|
if (raw_capacity) {
|
|
|
|
pr_err("cpu_capacity: missing %s raw capacity\n",
|
|
|
|
cpu_node->full_name);
|
|
|
|
pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
|
|
|
|
}
|
|
|
|
cap_parsing_failed = true;
|
|
|
|
kfree(raw_capacity);
|
|
|
|
}
|
|
|
|
|
|
|
|
return !ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef CONFIG_CPU_FREQ
|
|
|
|
static cpumask_var_t cpus_to_visit;
|
|
|
|
static bool cap_parsing_done;
|
|
|
|
static void parsing_done_workfn(struct work_struct *work);
|
|
|
|
static DECLARE_WORK(parsing_done_work, parsing_done_workfn);
|
|
|
|
|
|
|
|
static int
|
|
|
|
init_cpu_capacity_callback(struct notifier_block *nb,
|
|
|
|
unsigned long val,
|
|
|
|
void *data)
|
|
|
|
{
|
|
|
|
struct cpufreq_policy *policy = data;
|
|
|
|
int cpu;
|
|
|
|
|
|
|
|
if (cap_parsing_failed || cap_parsing_done)
|
|
|
|
return 0;
|
|
|
|
|
2017-06-23 09:25:31 +00:00
|
|
|
if (val != CPUFREQ_NOTIFY)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
pr_debug("cpu_capacity: init cpu capacity for CPUs [%*pbl] (to_visit=%*pbl)\n",
|
|
|
|
cpumask_pr_args(policy->related_cpus),
|
|
|
|
cpumask_pr_args(cpus_to_visit));
|
|
|
|
|
|
|
|
cpumask_andnot(cpus_to_visit, cpus_to_visit, policy->related_cpus);
|
|
|
|
|
|
|
|
for_each_cpu(cpu, policy->related_cpus) {
|
|
|
|
raw_capacity[cpu] = topology_get_cpu_scale(NULL, cpu) *
|
|
|
|
policy->cpuinfo.max_freq / 1000UL;
|
|
|
|
capacity_scale = max(raw_capacity[cpu], capacity_scale);
|
2017-05-31 16:59:28 +00:00
|
|
|
}
|
2017-06-23 09:25:31 +00:00
|
|
|
|
|
|
|
if (cpumask_empty(cpus_to_visit)) {
|
|
|
|
topology_normalize_cpu_scale();
|
|
|
|
kfree(raw_capacity);
|
|
|
|
pr_debug("cpu_capacity: parsing done\n");
|
|
|
|
cap_parsing_done = true;
|
|
|
|
schedule_work(&parsing_done_work);
|
|
|
|
}
|
|
|
|
|
2017-05-31 16:59:28 +00:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct notifier_block init_cpu_capacity_notifier = {
|
|
|
|
.notifier_call = init_cpu_capacity_callback,
|
|
|
|
};
|
|
|
|
|
|
|
|
static int __init register_cpufreq_notifier(void)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* on ACPI-based systems we need to use the default cpu capacity
|
|
|
|
* until we have the necessary code to parse the cpu capacity, so
|
|
|
|
* skip registering cpufreq notifier.
|
|
|
|
*/
|
2017-05-31 16:59:29 +00:00
|
|
|
if (!acpi_disabled || !raw_capacity)
|
2017-05-31 16:59:28 +00:00
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL)) {
|
|
|
|
pr_err("cpu_capacity: failed to allocate memory for cpus_to_visit\n");
|
|
|
|
return -ENOMEM;
|
|
|
|
}
|
|
|
|
|
|
|
|
cpumask_copy(cpus_to_visit, cpu_possible_mask);
|
|
|
|
|
|
|
|
return cpufreq_register_notifier(&init_cpu_capacity_notifier,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
|
|
|
}
|
|
|
|
core_initcall(register_cpufreq_notifier);
|
|
|
|
|
|
|
|
static void parsing_done_workfn(struct work_struct *work)
|
|
|
|
{
|
|
|
|
cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
|
|
|
}
|
|
|
|
|
|
|
|
#else
|
|
|
|
static int __init free_raw_capacity(void)
|
|
|
|
{
|
|
|
|
kfree(raw_capacity);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
core_initcall(free_raw_capacity);
|
|
|
|
#endif
|