[mirror_ubuntu-zesty-kernel.git] / arch / arm64 / kernel / topology.c

/*
 * arch/arm64/kernel/topology.c
 *
 * Copyright (C) 2011,2013,2014 Linaro Limited.
 *
 * Based on the arm32 version written by Vincent Guittot in turn based on
 * arch/sh/kernel/topology.c
 *
 * 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.
 */

#include <linux/acpi.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/percpu.h>
#include <linux/node.h>
#include <linux/nodemask.h>
#include <linux/of.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/cpufreq.h>

#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/topology.h>

static DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
static DEFINE_MUTEX(cpu_scale_mutex);

unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
{
	return per_cpu(cpu_scale, cpu);
}

static void set_capacity_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",
			arch_scale_cpu_capacity(NULL, cpu->dev.id));
}

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, i;
	unsigned long new_capacity;
	ssize_t ret;

	if (count) {
		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)
			set_capacity_scale(i, new_capacity);
		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;
static bool cap_parsing_failed;

static void __init parse_cpu_capacity(struct device_node *cpu_node, int cpu)
{
	int ret;
	u32 cpu_capacity;

	if (cap_parsing_failed)
		return;

	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) {
				pr_err("cpu_capacity: failed to allocate memory for raw capacities\n");
				cap_parsing_failed = true;
				return;
			}
		}
		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);
	}
}

static void normalize_cpu_capacity(void)
{
	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;
		set_capacity_scale(cpu, capacity);
		pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
			cpu, arch_scale_cpu_capacity(NULL, cpu));
	}
	mutex_unlock(&cpu_scale_mutex);
}

#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;

	switch (val) {
	case CPUFREQ_NOTIFY:
		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] = arch_scale_cpu_capacity(NULL, cpu) *
					    policy->cpuinfo.max_freq / 1000UL;
			capacity_scale = max(raw_capacity[cpu], capacity_scale);
		}
		if (cpumask_empty(cpus_to_visit)) {
			normalize_cpu_capacity();
			kfree(raw_capacity);
			pr_debug("cpu_capacity: parsing done\n");
			cap_parsing_done = true;
			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)
{
	/*
	 * 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 || cap_parsing_failed)
		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

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;

	for_each_possible_cpu(cpu) {
		if (of_get_cpu_node(cpu, NULL) == cpu_node) {
			parse_cpu_capacity(cpu_node, cpu);
			of_node_put(cpu_node);
			return cpu;
		}
	}

	pr_crit("Unable to find CPU node for %s\n", cpu_node->full_name);

	of_node_put(cpu_node);
	return -1;
}

static int __init parse_core(struct device_node *core, int cluster_id,
			     int core_id)
{
	char name[10];
	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].cluster_id = cluster_id;
				cpu_topology[cpu].core_id = core_id;
				cpu_topology[cpu].thread_id = i;
			} else {
				pr_err("%s: Can't get CPU for thread\n",
				       t->full_name);
				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("%s: Core has both threads and CPU\n",
			       core->full_name);
			return -EINVAL;
		}

		cpu_topology[cpu].cluster_id = cluster_id;
		cpu_topology[cpu].core_id = core_id;
	} else if (leaf) {
		pr_err("%s: Can't get CPU for leaf core\n", core->full_name);
		return -EINVAL;
	}

	return 0;
}

static int __init parse_cluster(struct device_node *cluster, int depth)
{
	char name[10];
	bool leaf = true;
	bool has_cores = false;
	struct device_node *c;
	static int cluster_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("%s: cpu-map children should be clusters\n",
				       c->full_name);
				of_node_put(c);
				return -EINVAL;
			}

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

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

	if (leaf && !has_cores)
		pr_warn("%s: empty cluster\n", cluster->full_name);

	if (leaf)
		cluster_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) {
		cap_parsing_failed = true;
		goto out;
	}

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

	normalize_cpu_capacity();

	/*
	 * 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].cluster_id == -1)
			ret = -EINVAL;

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

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

const struct cpumask *cpu_coregroup_mask(int cpu)
{
	return &cpu_topology[cpu].core_sibling;
}

static 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_possible_cpu(cpu) {
		cpu_topo = &cpu_topology[cpu];

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

		cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
		if (cpu != cpuid)
			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);
		if (cpu != cpuid)
			cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
	}
}

void store_cpu_topology(unsigned int cpuid)
{
	struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
	u64 mpidr;

	if (cpuid_topo->cluster_id != -1)
		goto topology_populated;

	mpidr = read_cpuid_mpidr();

	/* Uniprocessor systems can rely on default topology values */
	if (mpidr & MPIDR_UP_BITMASK)
		return;

	/* Create cpu topology mapping based on MPIDR. */
	if (mpidr & MPIDR_MT_BITMASK) {
		/* Multiprocessor system : Multi-threads per core */
		cpuid_topo->thread_id  = MPIDR_AFFINITY_LEVEL(mpidr, 0);
		cpuid_topo->core_id    = MPIDR_AFFINITY_LEVEL(mpidr, 1);
		cpuid_topo->cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 2) |
					 MPIDR_AFFINITY_LEVEL(mpidr, 3) << 8;
	} else {
		/* Multiprocessor system : Single-thread per core */
		cpuid_topo->thread_id  = -1;
		cpuid_topo->core_id    = MPIDR_AFFINITY_LEVEL(mpidr, 0);
		cpuid_topo->cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 1) |
					 MPIDR_AFFINITY_LEVEL(mpidr, 2) << 8 |
					 MPIDR_AFFINITY_LEVEL(mpidr, 3) << 16;
	}

	pr_debug("CPU%u: cluster %d core %d thread %d mpidr %#016llx\n",
		 cpuid, cpuid_topo->cluster_id, cpuid_topo->core_id,
		 cpuid_topo->thread_id, mpidr);

topology_populated:
	update_siblings_masks(cpuid);
}

static 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 = 0;
		cpu_topo->cluster_id = -1;

		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 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 (of_have_populated_dt() && parse_dt_topology())
		reset_cpu_topology();
}
Commit	Line	Data
f6e763b9 MB	1	/*
	2	* arch/arm64/kernel/topology.c
	3	*
	4	* Copyright (C) 2011,2013,2014 Linaro Limited.
	5	*
	6	* Based on the arm32 version written by Vincent Guittot in turn based on
	7	* arch/sh/kernel/topology.c
	8	*
	9	* This file is subject to the terms and conditions of the GNU General Public
	10	* License. See the file "COPYING" in the main directory of this archive
	11	* for more details.
	12	*/
	13
606f4226	14	#include <linux/acpi.h>
f6e763b9 MB	15	#include <linux/cpu.h>
	16	#include <linux/cpumask.h>
	17	#include <linux/init.h>
	18	#include <linux/percpu.h>
	19	#include <linux/node.h>
	20	#include <linux/nodemask.h>
ebdc9447	21	#include <linux/of.h>
f6e763b9	22	#include <linux/sched.h>
7202bde8	23	#include <linux/slab.h>
be8f185d	24	#include <linux/string.h>
7202bde8	25	#include <linux/cpufreq.h>
f6e763b9	26
be8f185d	27	#include <asm/cpu.h>
4e6f7084	28	#include <asm/cputype.h>
f6e763b9 MB	29	#include <asm/topology.h>
f6e763b9 MB	30
7202bde8	31	static DEFINE_PER_CPU(unsigned long, cpu_scale) = SCHED_CAPACITY_SCALE;
be8f185d	32	static DEFINE_MUTEX(cpu_scale_mutex);
7202bde8 JL	33
	34	unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
	35	{
	36	return per_cpu(cpu_scale, cpu);
	37	}
	38
	39	static void set_capacity_scale(unsigned int cpu, unsigned long capacity)
	40	{
	41	per_cpu(cpu_scale, cpu) = capacity;
	42	}
	43
be8f185d JL	44	static ssize_t cpu_capacity_show(struct device *dev,
	45	struct device_attribute *attr,
	46	char *buf)
	47	{
	48	struct cpu *cpu = container_of(dev, struct cpu, dev);
	49
	50	return sprintf(buf, "%lu\n",
	51	arch_scale_cpu_capacity(NULL, cpu->dev.id));
	52	}
	53
	54	static ssize_t cpu_capacity_store(struct device *dev,
	55	struct device_attribute *attr,
	56	const char *buf,
	57	size_t count)
	58	{
	59	struct cpu *cpu = container_of(dev, struct cpu, dev);
	60	int this_cpu = cpu->dev.id, i;
	61	unsigned long new_capacity;
	62	ssize_t ret;
	63
	64	if (count) {
	65	ret = kstrtoul(buf, 0, &new_capacity);
	66	if (ret)
	67	return ret;
	68	if (new_capacity > SCHED_CAPACITY_SCALE)
	69	return -EINVAL;
	70
	71	mutex_lock(&cpu_scale_mutex);
	72	for_each_cpu(i, &cpu_topology[this_cpu].core_sibling)
	73	set_capacity_scale(i, new_capacity);
	74	mutex_unlock(&cpu_scale_mutex);
	75	}
	76
	77	return count;
	78	}
	79
	80	static DEVICE_ATTR_RW(cpu_capacity);
	81
	82	static int register_cpu_capacity_sysctl(void)
	83	{
	84	int i;
	85	struct device *cpu;
	86
	87	for_each_possible_cpu(i) {
	88	cpu = get_cpu_device(i);
	89	if (!cpu) {
	90	pr_err("%s: too early to get CPU%d device!\n",
	91	__func__, i);
	92	continue;
	93	}
	94	device_create_file(cpu, &dev_attr_cpu_capacity);
	95	}
	96
	97	return 0;
	98	}
	99	subsys_initcall(register_cpu_capacity_sysctl);
be8f185d	100
7202bde8 JL	101	static u32 capacity_scale;
	102	static u32 *raw_capacity;
	103	static bool cap_parsing_failed;
	104
	105	static void __init parse_cpu_capacity(struct device_node *cpu_node, int cpu)
	106	{
	107	int ret;
	108	u32 cpu_capacity;
	109
	110	if (cap_parsing_failed)
	111	return;
	112
	113	ret = of_property_read_u32(cpu_node,
	114	"capacity-dmips-mhz",
	115	&cpu_capacity);
	116	if (!ret) {
	117	if (!raw_capacity) {
	118	raw_capacity = kcalloc(num_possible_cpus(),
	119	sizeof(*raw_capacity),
	120	GFP_KERNEL);
	121	if (!raw_capacity) {
	122	pr_err("cpu_capacity: failed to allocate memory for raw capacities\n");
	123	cap_parsing_failed = true;
	124	return;
	125	}
	126	}
	127	capacity_scale = max(cpu_capacity, capacity_scale);
	128	raw_capacity[cpu] = cpu_capacity;
	129	pr_debug("cpu_capacity: %s cpu_capacity=%u (raw)\n",
	130	cpu_node->full_name, raw_capacity[cpu]);
	131	} else {
	132	if (raw_capacity) {
	133	pr_err("cpu_capacity: missing %s raw capacity\n",
	134	cpu_node->full_name);
	135	pr_err("cpu_capacity: partial information: fallback to 1024 for all CPUs\n");
	136	}
	137	cap_parsing_failed = true;
	138	kfree(raw_capacity);
	139	}
	140	}
	141
	142	static void normalize_cpu_capacity(void)
	143	{
	144	u64 capacity;
	145	int cpu;
	146
	147	if (!raw_capacity \|\| cap_parsing_failed)
	148	return;
	149
	150	pr_debug("cpu_capacity: capacity_scale=%u\n", capacity_scale);
be8f185d	151	mutex_lock(&cpu_scale_mutex);
7202bde8 JL	152	for_each_possible_cpu(cpu) {
	153	pr_debug("cpu_capacity: cpu=%d raw_capacity=%u\n",
	154	cpu, raw_capacity[cpu]);
	155	capacity = (raw_capacity[cpu] << SCHED_CAPACITY_SHIFT)
	156	/ capacity_scale;
	157	set_capacity_scale(cpu, capacity);
	158	pr_debug("cpu_capacity: CPU%d cpu_capacity=%lu\n",
	159	cpu, arch_scale_cpu_capacity(NULL, cpu));
	160	}
be8f185d	161	mutex_unlock(&cpu_scale_mutex);
7202bde8 JL	162	}
	163
	164	#ifdef CONFIG_CPU_FREQ
	165	static cpumask_var_t cpus_to_visit;
	166	static bool cap_parsing_done;
	167	static void parsing_done_workfn(struct work_struct *work);
	168	static DECLARE_WORK(parsing_done_work, parsing_done_workfn);
	169
	170	static int
	171	init_cpu_capacity_callback(struct notifier_block *nb,
	172	unsigned long val,
	173	void *data)
	174	{
	175	struct cpufreq_policy *policy = data;
	176	int cpu;
	177
	178	if (cap_parsing_failed \|\| cap_parsing_done)
	179	return 0;
	180
	181	switch (val) {
	182	case CPUFREQ_NOTIFY:
	183	pr_debug("cpu_capacity: init cpu capacity for CPUs [%pbl] (to_visit=%pbl)\n",
	184	cpumask_pr_args(policy->related_cpus),
	185	cpumask_pr_args(cpus_to_visit));
	186	cpumask_andnot(cpus_to_visit,
	187	cpus_to_visit,
	188	policy->related_cpus);
	189	for_each_cpu(cpu, policy->related_cpus) {
	190	raw_capacity[cpu] = arch_scale_cpu_capacity(NULL, cpu) *
	191	policy->cpuinfo.max_freq / 1000UL;
	192	capacity_scale = max(raw_capacity[cpu], capacity_scale);
	193	}
	194	if (cpumask_empty(cpus_to_visit)) {
	195	normalize_cpu_capacity();
	196	kfree(raw_capacity);
	197	pr_debug("cpu_capacity: parsing done\n");
	198	cap_parsing_done = true;
	199	schedule_work(&parsing_done_work);
	200	}
	201	}
	202	return 0;
	203	}
	204
	205	static struct notifier_block init_cpu_capacity_notifier = {
	206	.notifier_call = init_cpu_capacity_callback,
	207	};
	208
	209	static int __init register_cpufreq_notifier(void)
	210	{
606f4226 PP	211	/*
	212	* on ACPI-based systems we need to use the default cpu capacity
	213	* until we have the necessary code to parse the cpu capacity, so
	214	* skip registering cpufreq notifier.
	215	*/
	216	if (!acpi_disabled \|\| cap_parsing_failed)
7202bde8 JL	217	return -EINVAL;
	218
	219	if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL)) {
	220	pr_err("cpu_capacity: failed to allocate memory for cpus_to_visit\n");
	221	return -ENOMEM;
	222	}
	223	cpumask_copy(cpus_to_visit, cpu_possible_mask);
	224
	225	return cpufreq_register_notifier(&init_cpu_capacity_notifier,
	226	CPUFREQ_POLICY_NOTIFIER);
	227	}
	228	core_initcall(register_cpufreq_notifier);
	229
	230	static void parsing_done_workfn(struct work_struct *work)
	231	{
	232	cpufreq_unregister_notifier(&init_cpu_capacity_notifier,
	233	CPUFREQ_POLICY_NOTIFIER);
	234	}
	235
	236	#else
	237	static int __init free_raw_capacity(void)
	238	{
	239	kfree(raw_capacity);
	240
	241	return 0;
	242	}
	243	core_initcall(free_raw_capacity);
	244	#endif
	245
ebdc9447 MB	246	static int __init get_cpu_for_node(struct device_node *node)
	247	{
	248	struct device_node *cpu_node;
	249	int cpu;
	250
	251	cpu_node = of_parse_phandle(node, "cpu", 0);
	252	if (!cpu_node)
	253	return -1;
	254
	255	for_each_possible_cpu(cpu) {
	256	if (of_get_cpu_node(cpu, NULL) == cpu_node) {
7202bde8	257	parse_cpu_capacity(cpu_node, cpu);
ebdc9447 MB	258	of_node_put(cpu_node);
	259	return cpu;
	260	}
	261	}
	262
	263	pr_crit("Unable to find CPU node for %s\n", cpu_node->full_name);
	264
	265	of_node_put(cpu_node);
	266	return -1;
	267	}
	268
	269	static int __init parse_core(struct device_node *core, int cluster_id,
	270	int core_id)
	271	{
	272	char name[10];
	273	bool leaf = true;
	274	int i = 0;
	275	int cpu;
	276	struct device_node *t;
	277
	278	do {
	279	snprintf(name, sizeof(name), "thread%d", i);
	280	t = of_get_child_by_name(core, name);
	281	if (t) {
	282	leaf = false;
	283	cpu = get_cpu_for_node(t);
	284	if (cpu >= 0) {
	285	cpu_topology[cpu].cluster_id = cluster_id;
	286	cpu_topology[cpu].core_id = core_id;
	287	cpu_topology[cpu].thread_id = i;
	288	} else {
	289	pr_err("%s: Can't get CPU for thread\n",
	290	t->full_name);
	291	of_node_put(t);
	292	return -EINVAL;
	293	}
	294	of_node_put(t);
	295	}
	296	i++;
	297	} while (t);
	298
	299	cpu = get_cpu_for_node(core);
	300	if (cpu >= 0) {
	301	if (!leaf) {
	302	pr_err("%s: Core has both threads and CPU\n",
	303	core->full_name);
	304	return -EINVAL;
	305	}
	306
	307	cpu_topology[cpu].cluster_id = cluster_id;
	308	cpu_topology[cpu].core_id = core_id;
	309	} else if (leaf) {
	310	pr_err("%s: Can't get CPU for leaf core\n", core->full_name);
	311	return -EINVAL;
	312	}
	313
	314	return 0;
	315	}
	316
	317	static int __init parse_cluster(struct device_node *cluster, int depth)
	318	{
	319	char name[10];
	320	bool leaf = true;
	321	bool has_cores = false;
322	struct device_node *c;
323	static int cluster_id __initdata;
324	int core_id = 0;
325	int i, ret;
326
327	/*
328	* First check for child clusters; we currently ignore any
329	* information about the nesting of clusters and present the
330	* scheduler with a flat list of them.
331	*/
332	i = 0;
333	do {
334	snprintf(name, sizeof(name), "cluster%d", i);
335	c = of_get_child_by_name(cluster, name);
336	if (c) {
337	leaf = false;
338	ret = parse_cluster(c, depth + 1);
339	of_node_put(c);
340	if (ret != 0)
341	return ret;
342	}
343	i++;
344	} while (c);
345
346	/* Now check for cores */
347	i = 0;
348	do {
349	snprintf(name, sizeof(name), "core%d", i);
350	c = of_get_child_by_name(cluster, name);
351	if (c) {
352	has_cores = true;
353
354	if (depth == 0) {
355	pr_err("%s: cpu-map children should be clusters\n",
356	c->full_name);
357	of_node_put(c);
358	return -EINVAL;
359	}
360
361	if (leaf) {
362	ret = parse_core(c, cluster_id, core_id++);
363	} else {
364	pr_err("%s: Non-leaf cluster with core %s\n",
365	cluster->full_name, name);
366	ret = -EINVAL;
367	}
368
369	of_node_put(c);
370	if (ret != 0)
371	return ret;
372	}
373	i++;
374	} while (c);
375
376	if (leaf && !has_cores)
377	pr_warn("%s: empty cluster\n", cluster->full_name);
378
379	if (leaf)
380	cluster_id++;
381
382	return 0;
383	}
384
385	static int __init parse_dt_topology(void)
386	{
387	struct device_node cn, map;
388	int ret = 0;
389	int cpu;
390
391	cn = of_find_node_by_path("/cpus");
392	if (!cn) {
393	pr_err("No CPU information found in DT\n");
394	return 0;
395	}
396
397	/*
398	* When topology is provided cpu-map is essentially a root
399	* cluster with restricted subnodes.
400	*/
401	map = of_get_child_by_name(cn, "cpu-map");
7202bde8 JL	402	if (!map) {
7202bde8 JL	403	cap_parsing_failed = true;
ebdc9447	404	goto out;
7202bde8	405	}
ebdc9447 MB	406
	407	ret = parse_cluster(map, 0);
	408	if (ret != 0)
	409	goto out_map;
	410
7202bde8 JL	411	normalize_cpu_capacity();
7202bde8 JL	412
ebdc9447 MB	413	/*
	414	* Check that all cores are in the topology; the SMP code will
	415	* only mark cores described in the DT as possible.
	416	*/
4e6f7084 ZSL	417	for_each_possible_cpu(cpu)
4e6f7084 ZSL	418	if (cpu_topology[cpu].cluster_id == -1)
ebdc9447	419	ret = -EINVAL;
ebdc9447 MB	420
	421	out_map:
	422	of_node_put(map);
	423	out:
	424	of_node_put(cn);
	425	return ret;
	426	}
	427
f6e763b9 MB	428	/*
	429	* cpu topology table
	430	*/
	431	struct cpu_topology cpu_topology[NR_CPUS];
	432	EXPORT_SYMBOL_GPL(cpu_topology);
	433
	434	const struct cpumask *cpu_coregroup_mask(int cpu)
	435	{
	436	return &cpu_topology[cpu].core_sibling;
	437	}
	438
	439	static void update_siblings_masks(unsigned int cpuid)
	440	{
	441	struct cpu_topology cpu_topo, cpuid_topo = &cpu_topology[cpuid];
	442	int cpu;
	443
f6e763b9 MB	444	/* update core and thread sibling masks */
	445	for_each_possible_cpu(cpu) {
	446	cpu_topo = &cpu_topology[cpu];
	447
	448	if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
	449	continue;
	450
	451	cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
	452	if (cpu != cpuid)
	453	cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
	454
	455	if (cpuid_topo->core_id != cpu_topo->core_id)
	456	continue;
	457
	458	cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
	459	if (cpu != cpuid)
	460	cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
	461	}
	462	}
	463
	464	void store_cpu_topology(unsigned int cpuid)
	465	{
4e6f7084 ZSL	466	struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
	467	u64 mpidr;
	468
	469	if (cpuid_topo->cluster_id != -1)
	470	goto topology_populated;
	471
	472	mpidr = read_cpuid_mpidr();
	473
	474	/* Uniprocessor systems can rely on default topology values */
	475	if (mpidr & MPIDR_UP_BITMASK)
	476	return;
	477
	478	/* Create cpu topology mapping based on MPIDR. */
	479	if (mpidr & MPIDR_MT_BITMASK) {
	480	/* Multiprocessor system : Multi-threads per core */
	481	cpuid_topo->thread_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
	482	cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
1cefdaea MB	483	cpuid_topo->cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 2) \|
1cefdaea MB	484	MPIDR_AFFINITY_LEVEL(mpidr, 3) << 8;
4e6f7084 ZSL	485	} else {
	486	/* Multiprocessor system : Single-thread per core */
	487	cpuid_topo->thread_id = -1;
	488	cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
1cefdaea MB	489	cpuid_topo->cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 1) \|
	490	MPIDR_AFFINITY_LEVEL(mpidr, 2) << 8 \|
	491	MPIDR_AFFINITY_LEVEL(mpidr, 3) << 16;
4e6f7084 ZSL	492	}
	493
	494	pr_debug("CPU%u: cluster %d core %d thread %d mpidr %#016llx\n",
	495	cpuid, cpuid_topo->cluster_id, cpuid_topo->core_id,
	496	cpuid_topo->thread_id, mpidr);
	497
	498	topology_populated:
f6e763b9 MB	499	update_siblings_masks(cpuid);
	500	}
	501
ebdc9447	502	static void __init reset_cpu_topology(void)
f6e763b9 MB	503	{
	504	unsigned int cpu;
	505
f6e763b9 MB	506	for_each_possible_cpu(cpu) {
	507	struct cpu_topology *cpu_topo = &cpu_topology[cpu];
	508
	509	cpu_topo->thread_id = -1;
c31bf048	510	cpu_topo->core_id = 0;
f6e763b9	511	cpu_topo->cluster_id = -1;
c31bf048	512
f6e763b9	513	cpumask_clear(&cpu_topo->core_sibling);
c31bf048	514	cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
f6e763b9	515	cpumask_clear(&cpu_topo->thread_sibling);
c31bf048	516	cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
f6e763b9 MB	517	}
f6e763b9 MB	518	}
ebdc9447 MB	519
	520	void __init init_cpu_topology(void)
	521	{
	522	reset_cpu_topology();
	523
	524	/*
	525	* Discard anything that was parsed if we hit an error so we
	526	* don't use partial information.
	527	*/
e094d445	528	if (of_have_populated_dt() && parse_dt_topology())
ebdc9447 MB	529	reset_cpu_topology();
ebdc9447 MB	530	}