diff options
Diffstat (limited to 'libdde-linux26/contrib/drivers/base/cpu.c')
-rw-r--r-- | libdde-linux26/contrib/drivers/base/cpu.c | 250 |
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; +} |