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-rw-r--r--libdde-linux26/contrib/drivers/base/cpu.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/libdde-linux26/contrib/drivers/base/cpu.c b/libdde-linux26/contrib/drivers/base/cpu.c
new file mode 100644
index 00000000..719ee5c1
--- /dev/null
+++ b/libdde-linux26/contrib/drivers/base/cpu.c
@@ -0,0 +1,250 @@
+/*
+ * drivers/base/cpu.c - basic CPU class support
+ */
+
+#include <linux/sysdev.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/cpu.h>
+#include <linux/topology.h>
+#include <linux/device.h>
+#include <linux/node.h>
+
+#include "base.h"
+
+struct sysdev_class cpu_sysdev_class = {
+ .name = "cpu",
+};
+EXPORT_SYMBOL(cpu_sysdev_class);
+
+static DEFINE_PER_CPU(struct sys_device *, cpu_sys_devices);
+
+#ifdef CONFIG_HOTPLUG_CPU
+static ssize_t show_online(struct sys_device *dev, struct sysdev_attribute *attr,
+ char *buf)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+
+ return sprintf(buf, "%u\n", !!cpu_online(cpu->sysdev.id));
+}
+
+static ssize_t __ref store_online(struct sys_device *dev, struct sysdev_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+ ssize_t ret;
+
+ switch (buf[0]) {
+ case '0':
+ ret = cpu_down(cpu->sysdev.id);
+ if (!ret)
+ kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
+ break;
+ case '1':
+ ret = cpu_up(cpu->sysdev.id);
+ if (!ret)
+ kobject_uevent(&dev->kobj, KOBJ_ONLINE);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ if (ret >= 0)
+ ret = count;
+ return ret;
+}
+static SYSDEV_ATTR(online, 0644, show_online, store_online);
+
+static void __cpuinit register_cpu_control(struct cpu *cpu)
+{
+ sysdev_create_file(&cpu->sysdev, &attr_online);
+}
+void unregister_cpu(struct cpu *cpu)
+{
+ int logical_cpu = cpu->sysdev.id;
+
+ unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu));
+
+ sysdev_remove_file(&cpu->sysdev, &attr_online);
+
+ sysdev_unregister(&cpu->sysdev);
+ per_cpu(cpu_sys_devices, logical_cpu) = NULL;
+ return;
+}
+#else /* ... !CONFIG_HOTPLUG_CPU */
+static inline void register_cpu_control(struct cpu *cpu)
+{
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+#ifdef CONFIG_KEXEC
+#include <linux/kexec.h>
+
+static ssize_t show_crash_notes(struct sys_device *dev, struct sysdev_attribute *attr,
+ char *buf)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+ ssize_t rc;
+ unsigned long long addr;
+ int cpunum;
+
+ cpunum = cpu->sysdev.id;
+
+ /*
+ * Might be reading other cpu's data based on which cpu read thread
+ * has been scheduled. But cpu data (memory) is allocated once during
+ * boot up and this data does not change there after. Hence this
+ * operation should be safe. No locking required.
+ */
+ addr = __pa(per_cpu_ptr(crash_notes, cpunum));
+ rc = sprintf(buf, "%Lx\n", addr);
+ return rc;
+}
+static SYSDEV_ATTR(crash_notes, 0400, show_crash_notes, NULL);
+#endif
+
+/*
+ * Print cpu online, possible, present, and system maps
+ */
+static ssize_t print_cpus_map(char *buf, cpumask_t *map)
+{
+ int n = cpulist_scnprintf(buf, PAGE_SIZE-2, map);
+
+ buf[n++] = '\n';
+ buf[n] = '\0';
+ return n;
+}
+
+#define print_cpus_func(type) \
+static ssize_t print_cpus_##type(struct sysdev_class *class, char *buf) \
+{ \
+ return print_cpus_map(buf, &cpu_##type##_map); \
+} \
+static struct sysdev_class_attribute attr_##type##_map = \
+ _SYSDEV_CLASS_ATTR(type, 0444, print_cpus_##type, NULL)
+
+print_cpus_func(online);
+print_cpus_func(possible);
+print_cpus_func(present);
+
+/*
+ * Print values for NR_CPUS and offlined cpus
+ */
+static ssize_t print_cpus_kernel_max(struct sysdev_class *class, char *buf)
+{
+ int n = snprintf(buf, PAGE_SIZE-2, "%d\n", NR_CPUS - 1);
+ return n;
+}
+static SYSDEV_CLASS_ATTR(kernel_max, 0444, print_cpus_kernel_max, NULL);
+
+/* arch-optional setting to enable display of offline cpus >= nr_cpu_ids */
+unsigned int total_cpus;
+
+static ssize_t print_cpus_offline(struct sysdev_class *class, char *buf)
+{
+ int n = 0, len = PAGE_SIZE-2;
+ cpumask_var_t offline;
+
+ /* display offline cpus < nr_cpu_ids */
+ if (!alloc_cpumask_var(&offline, GFP_KERNEL))
+ return -ENOMEM;
+ cpumask_complement(offline, cpu_online_mask);
+ n = cpulist_scnprintf(buf, len, offline);
+ free_cpumask_var(offline);
+
+ /* display offline cpus >= nr_cpu_ids */
+ if (total_cpus && nr_cpu_ids < total_cpus) {
+ if (n && n < len)
+ buf[n++] = ',';
+
+ if (nr_cpu_ids == total_cpus-1)
+ n += snprintf(&buf[n], len - n, "%d", nr_cpu_ids);
+ else
+ n += snprintf(&buf[n], len - n, "%d-%d",
+ nr_cpu_ids, total_cpus-1);
+ }
+
+ n += snprintf(&buf[n], len - n, "\n");
+ return n;
+}
+static SYSDEV_CLASS_ATTR(offline, 0444, print_cpus_offline, NULL);
+
+static struct sysdev_class_attribute *cpu_state_attr[] = {
+ &attr_online_map,
+ &attr_possible_map,
+ &attr_present_map,
+ &attr_kernel_max,
+ &attr_offline,
+};
+
+static int cpu_states_init(void)
+{
+ int i;
+ int err = 0;
+
+ for (i = 0; i < ARRAY_SIZE(cpu_state_attr); i++) {
+ int ret;
+ ret = sysdev_class_create_file(&cpu_sysdev_class,
+ cpu_state_attr[i]);
+ if (!err)
+ err = ret;
+ }
+ return err;
+}
+
+/*
+ * register_cpu - Setup a sysfs device for a CPU.
+ * @cpu - cpu->hotpluggable field set to 1 will generate a control file in
+ * sysfs for this CPU.
+ * @num - CPU number to use when creating the device.
+ *
+ * Initialize and register the CPU device.
+ */
+int __cpuinit register_cpu(struct cpu *cpu, int num)
+{
+ int error;
+ cpu->node_id = cpu_to_node(num);
+ cpu->sysdev.id = num;
+ cpu->sysdev.cls = &cpu_sysdev_class;
+
+ error = sysdev_register(&cpu->sysdev);
+
+ if (!error && cpu->hotpluggable)
+ register_cpu_control(cpu);
+ if (!error)
+ per_cpu(cpu_sys_devices, num) = &cpu->sysdev;
+ if (!error)
+ register_cpu_under_node(num, cpu_to_node(num));
+
+#ifdef CONFIG_KEXEC
+ if (!error)
+ error = sysdev_create_file(&cpu->sysdev, &attr_crash_notes);
+#endif
+ return error;
+}
+
+struct sys_device *get_cpu_sysdev(unsigned cpu)
+{
+ if (cpu < nr_cpu_ids && cpu_possible(cpu))
+ return per_cpu(cpu_sys_devices, cpu);
+ else
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(get_cpu_sysdev);
+
+int __init cpu_dev_init(void)
+{
+ int err;
+
+ err = sysdev_class_register(&cpu_sysdev_class);
+ if (!err)
+ err = cpu_states_init();
+
+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+ if (!err)
+ err = sched_create_sysfs_power_savings_entries(&cpu_sysdev_class);
+#endif
+
+ return err;
+}