drivers/base/arch_topology.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * Arch specific cpu topology information
  *
  * Copyright (C) 2016, ARM Ltd.
  * Written by: Juri Lelli, ARM Ltd.
  */

 #include <linux/acpi.h>
 #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>
 #include <linux/cpuset.h>
 #include <linux/cpumask.h>
 #include <linux/init.h>
 #include <linux/percpu.h>
 #include <linux/sched.h>
 #include <linux/smp.h>

 __weak bool arch_freq_counters_available(struct cpumask *cpus)
 {
 	return false;
 }
 DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE;

 void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq,
 			 unsigned long max_freq)
 {
 	unsigned long scale;
 	int i;

 	/*
 	 * If the use of counters for FIE is enabled, just return as we don't
 	 * want to update the scale factor with information from CPUFREQ.
 	 * Instead the scale factor will be updated from arch_scale_freq_tick.
 	 */
 	if (arch_freq_counters_available(cpus))
 		return;

 	scale = (cur_freq << SCHED_CAPACITY_SHIFT) / max_freq;

 	for_each_cpu(i, cpus)
 		per_cpu(freq_scale, i) = scale;
 }

 DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;

 void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
 {
 	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);

 	return sprintf(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
 }

 static void update_topology_flags_workfn(struct work_struct *work);
 static DECLARE_WORK(update_topology_flags_work, update_topology_flags_workfn);

 static DEVICE_ATTR_RO(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 int update_topology;

 int topology_update_cpu_topology(void)
 {
 	return update_topology;
 }

 /*
  * Updating the sched_domains can't be done directly from cpufreq callbacks
  * due to locking, so queue the work for later.
  */
 static void update_topology_flags_workfn(struct work_struct *work)
 {
 	update_topology = 1;
 	rebuild_sched_domains();
 	pr_debug("sched_domain hierarchy rebuilt, flags updated\n");
 	update_topology = 0;
 }

 static DEFINE_PER_CPU(u32, freq_factor) = 1;
 static u32 *raw_capacity;

 static int free_raw_capacity(void)
 {
 	kfree(raw_capacity);
 	raw_capacity = NULL;

 	return 0;
 }

 void topology_normalize_cpu_scale(void)
 {
 	u64 capacity;
 	u64 capacity_scale;
 	int cpu;

 	if (!raw_capacity)
 		return;

 	capacity_scale = 1;
 	for_each_possible_cpu(cpu) {
 		capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
 		capacity_scale = max(capacity, capacity_scale);
 	}

 	pr_debug("cpu_capacity: capacity_scale=%llu\n", capacity_scale);
 	for_each_possible_cpu(cpu) {
 		capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
 		capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
 			capacity_scale);
 		topology_set_cpu_scale(cpu, capacity);
 		pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
 			cpu, topology_get_cpu_scale(cpu));
 	}
 }

 bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
 {
 	struct clk *cpu_clk;
 	static bool cap_parsing_failed;
 	int ret;
 	u32 cpu_capacity;

 	if (cap_parsing_failed)
 		return false;

 	ret = of_property_read_u32(cpu_node, "capacity-dmips-mhz",
 				   &cpu_capacity);
 	if (!ret) {
 		if (!raw_capacity) {
 			raw_capacity = kcalloc(num_possible_cpus(),
 					       sizeof(*raw_capacity),
 					       GFP_KERNEL);
 			if (!raw_capacity) {
 				cap_parsing_failed = true;
 				return false;
 			}
 		}
 		raw_capacity[cpu] = cpu_capacity;
 		pr_debug("cpu_capacity: %pOF cpu_capacity=%u (raw)\n",
 			cpu_node, raw_capacity[cpu]);

 		/*
 		 * Update freq_factor for calculating early boot cpu capacities.
 		 * For non-clk CPU DVFS mechanism, there's no way to get the
 		 * frequency value now, assuming they are running at the same
 		 * frequency (by keeping the initial freq_factor value).
 		 */
 		cpu_clk = of_clk_get(cpu_node, 0);
 		if (!PTR_ERR_OR_ZERO(cpu_clk)) {
 			per_cpu(freq_factor, cpu) =
 				clk_get_rate(cpu_clk) / 1000;
 			clk_put(cpu_clk);
 		}
 	} else {
 		if (raw_capacity) {
 			pr_err("cpu_capacity: missing %pOF raw capacity\n",
 				cpu_node);
 			pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
 		}
 		cap_parsing_failed = true;
 		free_raw_capacity();
 	}

 	return !ret;
 }

 #ifdef CONFIG_CPU_FREQ
 static cpumask_var_t cpus_to_visit;
 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 (!raw_capacity)
 		return 0;

 	if (val != CPUFREQ_CREATE_POLICY)
 		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)
 		per_cpu(freq_factor, cpu) = policy->cpuinfo.max_freq / 1000;

 	if (cpumask_empty(cpus_to_visit)) {
 		topology_normalize_cpu_scale();
 		schedule_work(&update_topology_flags_work);
 		free_raw_capacity();
 		pr_debug("cpu_capacity: parsing done\n");
 		schedule_work(&parsing_done_work);
 	}

 	return 0;
 }

 static struct notifier_block init_cpu_capacity_notifier = {
 	.notifier_call = init_cpu_capacity_callback,
 };

 static int __init register_cpufreq_notifier(void)
 {
 	int ret;

 	/*
 	 * 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.
 	 */
 	if (!acpi_disabled || !raw_capacity)
 		return -EINVAL;

 	if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL))
 		return -ENOMEM;

 	cpumask_copy(cpus_to_visit, cpu_possible_mask);

 	ret = cpufreq_register_notifier(&init_cpu_capacity_notifier,
 					CPUFREQ_POLICY_NOTIFIER);

 	if (ret)
 		free_cpumask_var(cpus_to_visit);

 	return ret;
 }
 core_initcall(register_cpufreq_notifier);

 static void parsing_done_workfn(struct work_struct *work)
 {
 	cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
 					 CPUFREQ_POLICY_NOTIFIER);
 	free_cpumask_var(cpus_to_visit);
 }

 #else
 core_initcall(free_raw_capacity);
 #endif

 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
 /*
  * This function returns the logic cpu number of the node.
  * There are basically three kinds of return values:
  * (1) logic cpu number which is > 0.
  * (2) -ENODEV when the device tree(DT) node is valid and found in the DT but
  * there is no possible logical CPU in the kernel to match. This happens
  * when CONFIG_NR_CPUS is configure to be smaller than the number of
  * CPU nodes in DT. We need to just ignore this case.
  * (3) -1 if the node does not exist in the device tree
  */
 static int __init get_cpu_for_node(struct device_node *node)
 {
 	struct device_node *cpu_node;
 	int cpu;

 	cpu_node = of_parse_phandle(node, "cpu", 0);
 	if (!cpu_node)
 		return -1;

 	cpu = of_cpu_node_to_id(cpu_node);
 	if (cpu >= 0)
 		topology_parse_cpu_capacity(cpu_node, cpu);
 	else
 		pr_info("CPU node for %pOF exist but the possible cpu range is :%*pbl\n",
 			cpu_node, cpumask_pr_args(cpu_possible_mask));

 	of_node_put(cpu_node);
 	return cpu;
 }

 static int __init parse_core(struct device_node *core, int package_id,
 			     int core_id)
 {
 	char name[20];
 	bool leaf = true;
 	int i = 0;
 	int cpu;
 	struct device_node *t;

 	do {
 		snprintf(name, sizeof(name), "thread%d", i);
 		t = of_get_child_by_name(core, name);
 		if (t) {
 			leaf = false;
 			cpu = get_cpu_for_node(t);
 			if (cpu >= 0) {
 				cpu_topology[cpu].package_id = package_id;
 				cpu_topology[cpu].core_id = core_id;
 				cpu_topology[cpu].thread_id = i;
 			} else if (cpu != -ENODEV) {
 				pr_err("%pOF: Can't get CPU for thread\n", t);
 				of_node_put(t);
 				return -EINVAL;
 			}
 			of_node_put(t);
 		}
 		i++;
 	} while (t);

 	cpu = get_cpu_for_node(core);
 	if (cpu >= 0) {
 		if (!leaf) {
 			pr_err("%pOF: Core has both threads and CPU\n",
 			       core);
 			return -EINVAL;
 		}

 		cpu_topology[cpu].package_id = package_id;
 		cpu_topology[cpu].core_id = core_id;
 	} else if (leaf && cpu != -ENODEV) {
 		pr_err("%pOF: Can't get CPU for leaf core\n", core);
 		return -EINVAL;
 	}

 	return 0;
 }

 static int __init parse_cluster(struct device_node *cluster, int depth)
 {
 	char name[20];
 	bool leaf = true;
 	bool has_cores = false;
 	struct device_node *c;
 	static int package_id __initdata;
 	int core_id = 0;
 	int i, ret;

 	/*
 	 * First check for child clusters; we currently ignore any
 	 * information about the nesting of clusters and present the
 	 * scheduler with a flat list of them.
 	 */
 	i = 0;
 	do {
 		snprintf(name, sizeof(name), "cluster%d", i);
 		c = of_get_child_by_name(cluster, name);
 		if (c) {
 			leaf = false;
 			ret = parse_cluster(c, depth + 1);
 			of_node_put(c);
 			if (ret != 0)
 				return ret;
 		}
 		i++;
 	} while (c);

 	/* Now check for cores */
 	i = 0;
 	do {
 		snprintf(name, sizeof(name), "core%d", i);
 		c = of_get_child_by_name(cluster, name);
 		if (c) {
 			has_cores = true;

 			if (depth == 0) {
 				pr_err("%pOF: cpu-map children should be clusters\n",
 				       c);
 				of_node_put(c);
 				return -EINVAL;
 			}

 			if (leaf) {
 				ret = parse_core(c, package_id, core_id++);
 			} else {
 				pr_err("%pOF: Non-leaf cluster with core %s\n",
 				       cluster, name);
 				ret = -EINVAL;
 			}

 			of_node_put(c);
 			if (ret != 0)
 				return ret;
 		}
 		i++;
 	} while (c);

 	if (leaf && !has_cores)
 		pr_warn("%pOF: empty cluster\n", cluster);

 	if (leaf)
 		package_id++;

 	return 0;
 }

 static int __init parse_dt_topology(void)
 {
 	struct device_node *cn, *map;
 	int ret = 0;
 	int cpu;

 	cn = of_find_node_by_path("/cpus");
 	if (!cn) {
 		pr_err("No CPU information found in DT\n");
 		return 0;
 	}

 	/*
 	 * When topology is provided cpu-map is essentially a root
 	 * cluster with restricted subnodes.
 	 */
 	map = of_get_child_by_name(cn, "cpu-map");
 	if (!map)
 		goto out;

 	ret = parse_cluster(map, 0);
 	if (ret != 0)
 		goto out_map;

 	topology_normalize_cpu_scale();

 	/*
 	 * Check that all cores are in the topology; the SMP code will
 	 * only mark cores described in the DT as possible.
 	 */
 	for_each_possible_cpu(cpu)
 		if (cpu_topology[cpu].package_id == -1)
 			ret = -EINVAL;

 out_map:
 	of_node_put(map);
 out:
 	of_node_put(cn);
 	return ret;
 }
 #endif

 /*
  * cpu topology table
  */
 struct cpu_topology cpu_topology[NR_CPUS];
 EXPORT_SYMBOL_GPL(cpu_topology);

 const struct cpumask *cpu_coregroup_mask(int cpu)
 {
 	const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));

 	/* Find the smaller of NUMA, core or LLC siblings */
 	if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
 		/* not numa in package, lets use the package siblings */
 		core_mask = &cpu_topology[cpu].core_sibling;
 	}
 	if (cpu_topology[cpu].llc_id != -1) {
 		if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
 			core_mask = &cpu_topology[cpu].llc_sibling;
 	}

 	return core_mask;
 }

 void update_siblings_masks(unsigned int cpuid)
 {
 	struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
 	int cpu;

 	/* update core and thread sibling masks */
 	for_each_online_cpu(cpu) {
 		cpu_topo = &cpu_topology[cpu];

 		if (cpuid_topo->llc_id == cpu_topo->llc_id) {
 			cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
 			cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
 		}

 		if (cpuid_topo->package_id != cpu_topo->package_id)
 			continue;

 		cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
 		cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);

 		if (cpuid_topo->core_id != cpu_topo->core_id)
 			continue;

 		cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
 		cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
 	}
 }

 static void clear_cpu_topology(int cpu)
 {
 	struct cpu_topology *cpu_topo = &cpu_topology[cpu];

 	cpumask_clear(&cpu_topo->llc_sibling);
 	cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);

 	cpumask_clear(&cpu_topo->core_sibling);
 	cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
 	cpumask_clear(&cpu_topo->thread_sibling);
 	cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
 }

 void __init reset_cpu_topology(void)
 {
 	unsigned int cpu;

 	for_each_possible_cpu(cpu) {
 		struct cpu_topology *cpu_topo = &cpu_topology[cpu];

 		cpu_topo->thread_id = -1;
 		cpu_topo->core_id = -1;
 		cpu_topo->package_id = -1;
 		cpu_topo->llc_id = -1;

 		clear_cpu_topology(cpu);
 	}
 }

 void remove_cpu_topology(unsigned int cpu)
 {
 	int sibling;

 	for_each_cpu(sibling, topology_core_cpumask(cpu))
 		cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
 	for_each_cpu(sibling, topology_sibling_cpumask(cpu))
 		cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
 	for_each_cpu(sibling, topology_llc_cpumask(cpu))
 		cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));

 	clear_cpu_topology(cpu);
 }

 __weak int __init parse_acpi_topology(void)
 {
 	return 0;
 }

 #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
 void __init init_cpu_topology(void)
 {
 	reset_cpu_topology();

 	/*
 	 * Discard anything that was parsed if we hit an error so we
 	 * don't use partial information.
 	 */
 	if (parse_acpi_topology())
 		reset_cpu_topology();
 	else if (of_have_populated_dt() && parse_dt_topology())
 		reset_cpu_topology();
 }
 #endif
	// SPDX-License-Identifier: GPL-2.0
	/*
	* Arch specific cpu topology information
	*
	* Copyright (C) 2016, ARM Ltd.
	* Written by: Juri Lelli, ARM Ltd.
	*/

	#include <linux/acpi.h>
	#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>
	#include <linux/cpuset.h>
	#include <linux/cpumask.h>
	#include <linux/init.h>
	#include <linux/percpu.h>
	#include <linux/sched.h>
	#include <linux/smp.h>

	__weak bool arch_freq_counters_available(struct cpumask *cpus)
	{
	return false;
	}
	DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE;

	void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq,
	unsigned long max_freq)
	{
	unsigned long scale;
	int i;

	/*
	* If the use of counters for FIE is enabled, just return as we don't
	* want to update the scale factor with information from CPUFREQ.
	* Instead the scale factor will be updated from arch_scale_freq_tick.
	*/
	if (arch_freq_counters_available(cpus))
	return;

	scale = (cur_freq << SCHED_CAPACITY_SHIFT) / max_freq;

	for_each_cpu(i, cpus)
	per_cpu(freq_scale, i) = scale;
	}

	DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;

	void topology_set_cpu_scale(unsigned int cpu, unsigned long capacity)
	{
	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);

	return sprintf(buf, "%lu\n", topology_get_cpu_scale(cpu->dev.id));
	}

	static void update_topology_flags_workfn(struct work_struct *work);
	static DECLARE_WORK(update_topology_flags_work, update_topology_flags_workfn);

	static DEVICE_ATTR_RO(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 int update_topology;

	int topology_update_cpu_topology(void)
	{
	return update_topology;
	}

	/*
	* Updating the sched_domains can't be done directly from cpufreq callbacks
	* due to locking, so queue the work for later.
	*/
	static void update_topology_flags_workfn(struct work_struct *work)
	{
	update_topology = 1;
	rebuild_sched_domains();
	pr_debug("sched_domain hierarchy rebuilt, flags updated\n");
	update_topology = 0;
	}

	static DEFINE_PER_CPU(u32, freq_factor) = 1;
	static u32 *raw_capacity;

	static int free_raw_capacity(void)
	{
	kfree(raw_capacity);
	raw_capacity = NULL;

	return 0;
	}

	void topology_normalize_cpu_scale(void)
	{
	u64 capacity;
	u64 capacity_scale;
	int cpu;

	if (!raw_capacity)
	return;

	capacity_scale = 1;
	for_each_possible_cpu(cpu) {
	capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
	capacity_scale = max(capacity, capacity_scale);
	}

	pr_debug("cpu_capacity: capacity_scale=%llu\n", capacity_scale);
	for_each_possible_cpu(cpu) {
	capacity = raw_capacity[cpu] * per_cpu(freq_factor, cpu);
	capacity = div64_u64(capacity << SCHED_CAPACITY_SHIFT,
	capacity_scale);
	topology_set_cpu_scale(cpu, capacity);
	pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
	cpu, topology_get_cpu_scale(cpu));
	}
	}

	bool __init topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu)
	{
	struct clk *cpu_clk;
	static bool cap_parsing_failed;
	int ret;
	u32 cpu_capacity;

	if (cap_parsing_failed)
	return false;

	ret = of_property_read_u32(cpu_node, "capacity-dmips-mhz",
	&cpu_capacity);
	if (!ret) {
	if (!raw_capacity) {
	raw_capacity = kcalloc(num_possible_cpus(),
	sizeof(*raw_capacity),
	GFP_KERNEL);
	if (!raw_capacity) {
	cap_parsing_failed = true;
	return false;
	}
	}
	raw_capacity[cpu] = cpu_capacity;
	pr_debug("cpu_capacity: %pOF cpu_capacity=%u (raw)\n",
	cpu_node, raw_capacity[cpu]);

	/*
	* Update freq_factor for calculating early boot cpu capacities.
	* For non-clk CPU DVFS mechanism, there's no way to get the
	* frequency value now, assuming they are running at the same
	* frequency (by keeping the initial freq_factor value).
	*/
	cpu_clk = of_clk_get(cpu_node, 0);
	if (!PTR_ERR_OR_ZERO(cpu_clk)) {
	per_cpu(freq_factor, cpu) =
	clk_get_rate(cpu_clk) / 1000;
	clk_put(cpu_clk);
	}
	} else {
	if (raw_capacity) {
	pr_err("cpu_capacity: missing %pOF raw capacity\n",
	cpu_node);
	pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
	}
	cap_parsing_failed = true;
	free_raw_capacity();
	}

	return !ret;
	}

	#ifdef CONFIG_CPU_FREQ
	static cpumask_var_t cpus_to_visit;
	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 (!raw_capacity)
	return 0;

	if (val != CPUFREQ_CREATE_POLICY)
	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)
	per_cpu(freq_factor, cpu) = policy->cpuinfo.max_freq / 1000;

	if (cpumask_empty(cpus_to_visit)) {
	topology_normalize_cpu_scale();
	schedule_work(&update_topology_flags_work);
	free_raw_capacity();
	pr_debug("cpu_capacity: parsing done\n");
	schedule_work(&parsing_done_work);
	}

	return 0;
	}

	static struct notifier_block init_cpu_capacity_notifier = {
	.notifier_call = init_cpu_capacity_callback,
	};

	static int __init register_cpufreq_notifier(void)
	{
	int ret;

	/*
	* 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.
	*/
	if (!acpi_disabled \|\| !raw_capacity)
	return -EINVAL;

	if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL))
	return -ENOMEM;

	cpumask_copy(cpus_to_visit, cpu_possible_mask);

	ret = cpufreq_register_notifier(&init_cpu_capacity_notifier,
	CPUFREQ_POLICY_NOTIFIER);

	if (ret)
	free_cpumask_var(cpus_to_visit);

	return ret;
	}
	core_initcall(register_cpufreq_notifier);

	static void parsing_done_workfn(struct work_struct *work)
	{
	cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
	CPUFREQ_POLICY_NOTIFIER);
	free_cpumask_var(cpus_to_visit);
	}

	#else
	core_initcall(free_raw_capacity);
	#endif

	#if defined(CONFIG_ARM64) \|\| defined(CONFIG_RISCV)
	/*
	* This function returns the logic cpu number of the node.
	* There are basically three kinds of return values:
	* (1) logic cpu number which is > 0.
	* (2) -ENODEV when the device tree(DT) node is valid and found in the DT but
	* there is no possible logical CPU in the kernel to match. This happens
	* when CONFIG_NR_CPUS is configure to be smaller than the number of
	* CPU nodes in DT. We need to just ignore this case.
	* (3) -1 if the node does not exist in the device tree
	*/
	static int __init get_cpu_for_node(struct device_node *node)
	{
	struct device_node *cpu_node;
	int cpu;

	cpu_node = of_parse_phandle(node, "cpu", 0);
	if (!cpu_node)
	return -1;

	cpu = of_cpu_node_to_id(cpu_node);
	if (cpu >= 0)
	topology_parse_cpu_capacity(cpu_node, cpu);
	else
	pr_info("CPU node for %pOF exist but the possible cpu range is :%*pbl\n",
	cpu_node, cpumask_pr_args(cpu_possible_mask));

	of_node_put(cpu_node);
	return cpu;
	}

	static int __init parse_core(struct device_node *core, int package_id,
	int core_id)
	{
	char name[20];
	bool leaf = true;
	int i = 0;
	int cpu;
	struct device_node *t;

	do {
	snprintf(name, sizeof(name), "thread%d", i);
	t = of_get_child_by_name(core, name);
	if (t) {
	leaf = false;
	cpu = get_cpu_for_node(t);
	if (cpu >= 0) {
	cpu_topology[cpu].package_id = package_id;
	cpu_topology[cpu].core_id = core_id;
	cpu_topology[cpu].thread_id = i;
	} else if (cpu != -ENODEV) {
	pr_err("%pOF: Can't get CPU for thread\n", t);
	of_node_put(t);
	return -EINVAL;
	}
	of_node_put(t);
	}
	i++;
	} while (t);

	cpu = get_cpu_for_node(core);
	if (cpu >= 0) {
	if (!leaf) {
	pr_err("%pOF: Core has both threads and CPU\n",
	core);
	return -EINVAL;
	}

	cpu_topology[cpu].package_id = package_id;
	cpu_topology[cpu].core_id = core_id;
	} else if (leaf && cpu != -ENODEV) {
	pr_err("%pOF: Can't get CPU for leaf core\n", core);
	return -EINVAL;
	}

	return 0;
	}

	static int __init parse_cluster(struct device_node *cluster, int depth)
	{
	char name[20];
	bool leaf = true;
	bool has_cores = false;
	struct device_node *c;
	static int package_id __initdata;
	int core_id = 0;
	int i, ret;

	/*
	* First check for child clusters; we currently ignore any
	* information about the nesting of clusters and present the
	* scheduler with a flat list of them.
	*/
	i = 0;
	do {
	snprintf(name, sizeof(name), "cluster%d", i);
	c = of_get_child_by_name(cluster, name);
	if (c) {
	leaf = false;
	ret = parse_cluster(c, depth + 1);
	of_node_put(c);
	if (ret != 0)
	return ret;
	}
	i++;
	} while (c);

	/* Now check for cores */
	i = 0;
	do {
	snprintf(name, sizeof(name), "core%d", i);
	c = of_get_child_by_name(cluster, name);
	if (c) {
	has_cores = true;

	if (depth == 0) {
	pr_err("%pOF: cpu-map children should be clusters\n",
	c);
	of_node_put(c);
	return -EINVAL;
	}

	if (leaf) {
	ret = parse_core(c, package_id, core_id++);
	} else {
	pr_err("%pOF: Non-leaf cluster with core %s\n",
	cluster, name);
	ret = -EINVAL;
	}

	of_node_put(c);
	if (ret != 0)
	return ret;
	}
	i++;
	} while (c);

	if (leaf && !has_cores)
	pr_warn("%pOF: empty cluster\n", cluster);

	if (leaf)
	package_id++;

	return 0;
	}

	static int __init parse_dt_topology(void)
	{
	struct device_node cn, map;
	int ret = 0;
	int cpu;

	cn = of_find_node_by_path("/cpus");
	if (!cn) {
	pr_err("No CPU information found in DT\n");
	return 0;
	}

	/*
	* When topology is provided cpu-map is essentially a root
	* cluster with restricted subnodes.
	*/
	map = of_get_child_by_name(cn, "cpu-map");
	if (!map)
	goto out;

	ret = parse_cluster(map, 0);
	if (ret != 0)
	goto out_map;

	topology_normalize_cpu_scale();

	/*
	* Check that all cores are in the topology; the SMP code will
	* only mark cores described in the DT as possible.
	*/
	for_each_possible_cpu(cpu)
	if (cpu_topology[cpu].package_id == -1)
	ret = -EINVAL;

	out_map:
	of_node_put(map);
	out:
	of_node_put(cn);
	return ret;
	}
	#endif

	/*
	* cpu topology table
	*/
	struct cpu_topology cpu_topology[NR_CPUS];
	EXPORT_SYMBOL_GPL(cpu_topology);

	const struct cpumask *cpu_coregroup_mask(int cpu)
	{
	const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));

	/* Find the smaller of NUMA, core or LLC siblings */
	if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
	/* not numa in package, lets use the package siblings */
	core_mask = &cpu_topology[cpu].core_sibling;
	}
	if (cpu_topology[cpu].llc_id != -1) {
	if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
	core_mask = &cpu_topology[cpu].llc_sibling;
	}

	return core_mask;
	}

	void update_siblings_masks(unsigned int cpuid)
	{
	struct cpu_topology cpu_topo, cpuid_topo = &cpu_topology[cpuid];
	int cpu;

	/* update core and thread sibling masks */
	for_each_online_cpu(cpu) {
	cpu_topo = &cpu_topology[cpu];

	if (cpuid_topo->llc_id == cpu_topo->llc_id) {
	cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
	cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
	}

	if (cpuid_topo->package_id != cpu_topo->package_id)
	continue;

	cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
	cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);

	if (cpuid_topo->core_id != cpu_topo->core_id)
	continue;

	cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
	cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
	}
	}

	static void clear_cpu_topology(int cpu)
	{
	struct cpu_topology *cpu_topo = &cpu_topology[cpu];

	cpumask_clear(&cpu_topo->llc_sibling);
	cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);

	cpumask_clear(&cpu_topo->core_sibling);
	cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
	cpumask_clear(&cpu_topo->thread_sibling);
	cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
	}

	void __init reset_cpu_topology(void)
	{
	unsigned int cpu;

	for_each_possible_cpu(cpu) {
	struct cpu_topology *cpu_topo = &cpu_topology[cpu];

	cpu_topo->thread_id = -1;
	cpu_topo->core_id = -1;
	cpu_topo->package_id = -1;
	cpu_topo->llc_id = -1;

	clear_cpu_topology(cpu);
	}
	}

	void remove_cpu_topology(unsigned int cpu)
	{
	int sibling;

	for_each_cpu(sibling, topology_core_cpumask(cpu))
	cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
	for_each_cpu(sibling, topology_sibling_cpumask(cpu))
	cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
	for_each_cpu(sibling, topology_llc_cpumask(cpu))
	cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));

	clear_cpu_topology(cpu);
	}

	__weak int __init parse_acpi_topology(void)
	{
	return 0;
	}

	#if defined(CONFIG_ARM64) \|\| defined(CONFIG_RISCV)
	void __init init_cpu_topology(void)
	{
	reset_cpu_topology();

	/*
	* Discard anything that was parsed if we hit an error so we
	* don't use partial information.
	*/
	if (parse_acpi_topology())
	reset_cpu_topology();
	else if (of_have_populated_dt() && parse_dt_topology())
	reset_cpu_topology();
	}
	#endif