1 files changed, 618 insertions, 0 deletions

diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
new file mode 100644
index 000000000..51647926e
--- /dev/null
+++ b/drivers/base/arch_topology.c
@@ -0,0 +1,618 @@
+// 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>
+
+bool topology_scale_freq_invariant(void)
+{
+	return cpufreq_supports_freq_invariance() ||
+	       arch_freq_counters_available(cpu_online_mask);
+}
+
+__weak bool arch_freq_counters_available(const struct cpumask *cpus)
+{
+	return false;
+}
+DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE;
+
+void topology_set_freq_scale(const struct cpumask *cpus, unsigned long cur_freq,
+			     unsigned long max_freq)
+{
+	unsigned long scale;
+	int i;
+
+	if (WARN_ON_ONCE(!cur_freq || !max_freq))
+		return;
+
+	/*
+	 * 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;
+}
+
+DEFINE_PER_CPU(unsigned long, thermal_pressure);
+
+void topology_set_thermal_pressure(const struct cpumask *cpus,
+			       unsigned long th_pressure)
+{
+	int cpu;
+
+	for_each_cpu(cpu, cpus)
+		WRITE_ONCE(per_cpu(thermal_pressure, cpu), th_pressure);
+}
+
+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 sysfs_emit(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 (cpu_topo->llc_id != -1 && 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();
+}
+
+void store_cpu_topology(unsigned int cpuid)
+{
+	struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
+
+	if (cpuid_topo->package_id != -1)
+		goto topology_populated;
+
+	cpuid_topo->thread_id = -1;
+	cpuid_topo->core_id = cpuid;
+	cpuid_topo->package_id = cpu_to_node(cpuid);
+
+	pr_debug("CPU%u: package %d core %d thread %d\n",
+		 cpuid, cpuid_topo->package_id, cpuid_topo->core_id,
+		 cpuid_topo->thread_id);
+
+topology_populated:
+	update_siblings_masks(cpuid);
+}
+#endif