diff options
Diffstat (limited to 'tools/power/cpupower/lib/sysfs.c')
| -rw-r--r-- | tools/power/cpupower/lib/sysfs.c | 672 |
1 files changed, 0 insertions, 672 deletions
diff --git a/tools/power/cpupower/lib/sysfs.c b/tools/power/cpupower/lib/sysfs.c deleted file mode 100644 index 870713a75a81..000000000000 --- a/tools/power/cpupower/lib/sysfs.c +++ /dev/null @@ -1,672 +0,0 @@ -/* - * (C) 2004-2009 Dominik Brodowski <linux@dominikbrodowski.de> - * - * Licensed under the terms of the GNU GPL License version 2. - */ - -#include <stdio.h> -#include <errno.h> -#include <stdlib.h> -#include <string.h> -#include <limits.h> -#include <sys/types.h> -#include <sys/stat.h> -#include <fcntl.h> -#include <unistd.h> - -#include "cpufreq.h" - -#define PATH_TO_CPU "/sys/devices/system/cpu/" -#define MAX_LINE_LEN 4096 -#define SYSFS_PATH_MAX 255 - - -static unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen) -{ - int fd; - ssize_t numread; - - fd = open(path, O_RDONLY); - if (fd == -1) - return 0; - - numread = read(fd, buf, buflen - 1); - if (numread < 1) { - close(fd); - return 0; - } - - buf[numread] = '\0'; - close(fd); - - return (unsigned int) numread; -} - - -/* CPUFREQ sysfs access **************************************************/ - -/* helper function to read file from /sys into given buffer */ -/* fname is a relative path under "cpuX/cpufreq" dir */ -static unsigned int sysfs_cpufreq_read_file(unsigned int cpu, const char *fname, - char *buf, size_t buflen) -{ - char path[SYSFS_PATH_MAX]; - - snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/cpufreq/%s", - cpu, fname); - return sysfs_read_file(path, buf, buflen); -} - -/* helper function to write a new value to a /sys file */ -/* fname is a relative path under "cpuX/cpufreq" dir */ -static unsigned int sysfs_cpufreq_write_file(unsigned int cpu, - const char *fname, - const char *value, size_t len) -{ - char path[SYSFS_PATH_MAX]; - int fd; - ssize_t numwrite; - - snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/cpufreq/%s", - cpu, fname); - - fd = open(path, O_WRONLY); - if (fd == -1) - return 0; - - numwrite = write(fd, value, len); - if (numwrite < 1) { - close(fd); - return 0; - } - - close(fd); - - return (unsigned int) numwrite; -} - -/* read access to files which contain one numeric value */ - -enum cpufreq_value { - CPUINFO_CUR_FREQ, - CPUINFO_MIN_FREQ, - CPUINFO_MAX_FREQ, - CPUINFO_LATENCY, - SCALING_CUR_FREQ, - SCALING_MIN_FREQ, - SCALING_MAX_FREQ, - STATS_NUM_TRANSITIONS, - MAX_CPUFREQ_VALUE_READ_FILES -}; - -static const char *cpufreq_value_files[MAX_CPUFREQ_VALUE_READ_FILES] = { - [CPUINFO_CUR_FREQ] = "cpuinfo_cur_freq", - [CPUINFO_MIN_FREQ] = "cpuinfo_min_freq", - [CPUINFO_MAX_FREQ] = "cpuinfo_max_freq", - [CPUINFO_LATENCY] = "cpuinfo_transition_latency", - [SCALING_CUR_FREQ] = "scaling_cur_freq", - [SCALING_MIN_FREQ] = "scaling_min_freq", - [SCALING_MAX_FREQ] = "scaling_max_freq", - [STATS_NUM_TRANSITIONS] = "stats/total_trans" -}; - - -static unsigned long sysfs_cpufreq_get_one_value(unsigned int cpu, - enum cpufreq_value which) -{ - unsigned long value; - unsigned int len; - char linebuf[MAX_LINE_LEN]; - char *endp; - - if (which >= MAX_CPUFREQ_VALUE_READ_FILES) - return 0; - - len = sysfs_cpufreq_read_file(cpu, cpufreq_value_files[which], - linebuf, sizeof(linebuf)); - - if (len == 0) - return 0; - - value = strtoul(linebuf, &endp, 0); - - if (endp == linebuf || errno == ERANGE) - return 0; - - return value; -} - -/* read access to files which contain one string */ - -enum cpufreq_string { - SCALING_DRIVER, - SCALING_GOVERNOR, - MAX_CPUFREQ_STRING_FILES -}; - -static const char *cpufreq_string_files[MAX_CPUFREQ_STRING_FILES] = { - [SCALING_DRIVER] = "scaling_driver", - [SCALING_GOVERNOR] = "scaling_governor", -}; - - -static char *sysfs_cpufreq_get_one_string(unsigned int cpu, - enum cpufreq_string which) -{ - char linebuf[MAX_LINE_LEN]; - char *result; - unsigned int len; - - if (which >= MAX_CPUFREQ_STRING_FILES) - return NULL; - - len = sysfs_cpufreq_read_file(cpu, cpufreq_string_files[which], - linebuf, sizeof(linebuf)); - if (len == 0) - return NULL; - - result = strdup(linebuf); - if (result == NULL) - return NULL; - - if (result[strlen(result) - 1] == '\n') - result[strlen(result) - 1] = '\0'; - - return result; -} - -/* write access */ - -enum cpufreq_write { - WRITE_SCALING_MIN_FREQ, - WRITE_SCALING_MAX_FREQ, - WRITE_SCALING_GOVERNOR, - WRITE_SCALING_SET_SPEED, - MAX_CPUFREQ_WRITE_FILES -}; - -static const char *cpufreq_write_files[MAX_CPUFREQ_WRITE_FILES] = { - [WRITE_SCALING_MIN_FREQ] = "scaling_min_freq", - [WRITE_SCALING_MAX_FREQ] = "scaling_max_freq", - [WRITE_SCALING_GOVERNOR] = "scaling_governor", - [WRITE_SCALING_SET_SPEED] = "scaling_setspeed", -}; - -static int sysfs_cpufreq_write_one_value(unsigned int cpu, - enum cpufreq_write which, - const char *new_value, size_t len) -{ - if (which >= MAX_CPUFREQ_WRITE_FILES) - return 0; - - if (sysfs_cpufreq_write_file(cpu, cpufreq_write_files[which], - new_value, len) != len) - return -ENODEV; - - return 0; -}; - -unsigned long sysfs_get_freq_kernel(unsigned int cpu) -{ - return sysfs_cpufreq_get_one_value(cpu, SCALING_CUR_FREQ); -} - -unsigned long sysfs_get_freq_hardware(unsigned int cpu) -{ - return sysfs_cpufreq_get_one_value(cpu, CPUINFO_CUR_FREQ); -} - -unsigned long sysfs_get_freq_transition_latency(unsigned int cpu) -{ - return sysfs_cpufreq_get_one_value(cpu, CPUINFO_LATENCY); -} - -int sysfs_get_freq_hardware_limits(unsigned int cpu, - unsigned long *min, - unsigned long *max) -{ - if ((!min) || (!max)) - return -EINVAL; - - *min = sysfs_cpufreq_get_one_value(cpu, CPUINFO_MIN_FREQ); - if (!*min) - return -ENODEV; - - *max = sysfs_cpufreq_get_one_value(cpu, CPUINFO_MAX_FREQ); - if (!*max) - return -ENODEV; - - return 0; -} - -char *sysfs_get_freq_driver(unsigned int cpu) -{ - return sysfs_cpufreq_get_one_string(cpu, SCALING_DRIVER); -} - -struct cpufreq_policy *sysfs_get_freq_policy(unsigned int cpu) -{ - struct cpufreq_policy *policy; - - policy = malloc(sizeof(struct cpufreq_policy)); - if (!policy) - return NULL; - - policy->governor = sysfs_cpufreq_get_one_string(cpu, SCALING_GOVERNOR); - if (!policy->governor) { - free(policy); - return NULL; - } - policy->min = sysfs_cpufreq_get_one_value(cpu, SCALING_MIN_FREQ); - policy->max = sysfs_cpufreq_get_one_value(cpu, SCALING_MAX_FREQ); - if ((!policy->min) || (!policy->max)) { - free(policy->governor); - free(policy); - return NULL; - } - - return policy; -} - -struct cpufreq_available_governors * -sysfs_get_freq_available_governors(unsigned int cpu) { - struct cpufreq_available_governors *first = NULL; - struct cpufreq_available_governors *current = NULL; - char linebuf[MAX_LINE_LEN]; - unsigned int pos, i; - unsigned int len; - - len = sysfs_cpufreq_read_file(cpu, "scaling_available_governors", - linebuf, sizeof(linebuf)); - if (len == 0) - return NULL; - - pos = 0; - for (i = 0; i < len; i++) { - if (linebuf[i] == ' ' || linebuf[i] == '\n') { - if (i - pos < 2) - continue; - if (current) { - current->next = malloc(sizeof(*current)); - if (!current->next) - goto error_out; - current = current->next; - } else { - first = malloc(sizeof(*first)); - if (!first) - goto error_out; - current = first; - } - current->first = first; - current->next = NULL; - - current->governor = malloc(i - pos + 1); - if (!current->governor) - goto error_out; - - memcpy(current->governor, linebuf + pos, i - pos); - current->governor[i - pos] = '\0'; - pos = i + 1; - } - } - - return first; - - error_out: - while (first) { - current = first->next; - if (first->governor) - free(first->governor); - free(first); - first = current; - } - return NULL; -} - - -struct cpufreq_available_frequencies * -sysfs_get_available_frequencies(unsigned int cpu) { - struct cpufreq_available_frequencies *first = NULL; - struct cpufreq_available_frequencies *current = NULL; - char one_value[SYSFS_PATH_MAX]; - char linebuf[MAX_LINE_LEN]; - unsigned int pos, i; - unsigned int len; - - len = sysfs_cpufreq_read_file(cpu, "scaling_available_frequencies", - linebuf, sizeof(linebuf)); - if (len == 0) - return NULL; - - pos = 0; - for (i = 0; i < len; i++) { - if (linebuf[i] == ' ' || linebuf[i] == '\n') { - if (i - pos < 2) - continue; - if (i - pos >= SYSFS_PATH_MAX) - goto error_out; - if (current) { - current->next = malloc(sizeof(*current)); - if (!current->next) - goto error_out; - current = current->next; - } else { - first = malloc(sizeof(*first)); - if (!first) - goto error_out; - current = first; - } - current->first = first; - current->next = NULL; - - memcpy(one_value, linebuf + pos, i - pos); - one_value[i - pos] = '\0'; - if (sscanf(one_value, "%lu", ¤t->frequency) != 1) - goto error_out; - - pos = i + 1; - } - } - - return first; - - error_out: - while (first) { - current = first->next; - free(first); - first = current; - } - return NULL; -} - -static struct cpufreq_affected_cpus *sysfs_get_cpu_list(unsigned int cpu, - const char *file) -{ - struct cpufreq_affected_cpus *first = NULL; - struct cpufreq_affected_cpus *current = NULL; - char one_value[SYSFS_PATH_MAX]; - char linebuf[MAX_LINE_LEN]; - unsigned int pos, i; - unsigned int len; - - len = sysfs_cpufreq_read_file(cpu, file, linebuf, sizeof(linebuf)); - if (len == 0) - return NULL; - - pos = 0; - for (i = 0; i < len; i++) { - if (i == len || linebuf[i] == ' ' || linebuf[i] == '\n') { - if (i - pos < 1) - continue; - if (i - pos >= SYSFS_PATH_MAX) - goto error_out; - if (current) { - current->next = malloc(sizeof(*current)); - if (!current->next) - goto error_out; - current = current->next; - } else { - first = malloc(sizeof(*first)); - if (!first) - goto error_out; - current = first; - } - current->first = first; - current->next = NULL; - - memcpy(one_value, linebuf + pos, i - pos); - one_value[i - pos] = '\0'; - - if (sscanf(one_value, "%u", ¤t->cpu) != 1) - goto error_out; - - pos = i + 1; - } - } - - return first; - - error_out: - while (first) { - current = first->next; - free(first); - first = current; - } - return NULL; -} - -struct cpufreq_affected_cpus *sysfs_get_freq_affected_cpus(unsigned int cpu) -{ - return sysfs_get_cpu_list(cpu, "affected_cpus"); -} - -struct cpufreq_affected_cpus *sysfs_get_freq_related_cpus(unsigned int cpu) -{ - return sysfs_get_cpu_list(cpu, "related_cpus"); -} - -struct cpufreq_stats *sysfs_get_freq_stats(unsigned int cpu, - unsigned long long *total_time) { - struct cpufreq_stats *first = NULL; - struct cpufreq_stats *current = NULL; - char one_value[SYSFS_PATH_MAX]; - char linebuf[MAX_LINE_LEN]; - unsigned int pos, i; - unsigned int len; - - len = sysfs_cpufreq_read_file(cpu, "stats/time_in_state", - linebuf, sizeof(linebuf)); - if (len == 0) - return NULL; - - *total_time = 0; - pos = 0; - for (i = 0; i < len; i++) { - if (i == strlen(linebuf) || linebuf[i] == '\n') { - if (i - pos < 2) - continue; - if ((i - pos) >= SYSFS_PATH_MAX) - goto error_out; - if (current) { - current->next = malloc(sizeof(*current)); - if (!current->next) - goto error_out; - current = current->next; - } else { - first = malloc(sizeof(*first)); - if (!first) - goto error_out; - current = first; - } - current->first = first; - current->next = NULL; - - memcpy(one_value, linebuf + pos, i - pos); - one_value[i - pos] = '\0'; - if (sscanf(one_value, "%lu %llu", - ¤t->frequency, - ¤t->time_in_state) != 2) - goto error_out; - - *total_time = *total_time + current->time_in_state; - pos = i + 1; - } - } - - return first; - - error_out: - while (first) { - current = first->next; - free(first); - first = current; - } - return NULL; -} - -unsigned long sysfs_get_freq_transitions(unsigned int cpu) -{ - return sysfs_cpufreq_get_one_value(cpu, STATS_NUM_TRANSITIONS); -} - -static int verify_gov(char *new_gov, char *passed_gov) -{ - unsigned int i, j = 0; - - if (!passed_gov || (strlen(passed_gov) > 19)) - return -EINVAL; - - strncpy(new_gov, passed_gov, 20); - for (i = 0; i < 20; i++) { - if (j) { - new_gov[i] = '\0'; - continue; - } - if ((new_gov[i] >= 'a') && (new_gov[i] <= 'z')) - continue; - - if ((new_gov[i] >= 'A') && (new_gov[i] <= 'Z')) - continue; - - if (new_gov[i] == '-') - continue; - - if (new_gov[i] == '_') - continue; - - if (new_gov[i] == '\0') { - j = 1; - continue; - } - return -EINVAL; - } - new_gov[19] = '\0'; - return 0; -} - -int sysfs_modify_freq_policy_governor(unsigned int cpu, char *governor) -{ - char new_gov[SYSFS_PATH_MAX]; - - if (!governor) - return -EINVAL; - - if (verify_gov(new_gov, governor)) - return -EINVAL; - - return sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_GOVERNOR, - new_gov, strlen(new_gov)); -}; - -int sysfs_modify_freq_policy_max(unsigned int cpu, unsigned long max_freq) -{ - char value[SYSFS_PATH_MAX]; - - snprintf(value, SYSFS_PATH_MAX, "%lu", max_freq); - - return sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_MAX_FREQ, - value, strlen(value)); -}; - - -int sysfs_modify_freq_policy_min(unsigned int cpu, unsigned long min_freq) -{ - char value[SYSFS_PATH_MAX]; - - snprintf(value, SYSFS_PATH_MAX, "%lu", min_freq); - - return sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_MIN_FREQ, - value, strlen(value)); -}; - - -int sysfs_set_freq_policy(unsigned int cpu, struct cpufreq_policy *policy) -{ - char min[SYSFS_PATH_MAX]; - char max[SYSFS_PATH_MAX]; - char gov[SYSFS_PATH_MAX]; - int ret; - unsigned long old_min; - int write_max_first; - - if (!policy || !(policy->governor)) - return -EINVAL; - - if (policy->max < policy->min) - return -EINVAL; - - if (verify_gov(gov, policy->governor)) - return -EINVAL; - - snprintf(min, SYSFS_PATH_MAX, "%lu", policy->min); - snprintf(max, SYSFS_PATH_MAX, "%lu", policy->max); - - old_min = sysfs_cpufreq_get_one_value(cpu, SCALING_MIN_FREQ); - write_max_first = (old_min && (policy->max < old_min) ? 0 : 1); - - if (write_max_first) { - ret = sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_MAX_FREQ, - max, strlen(max)); - if (ret) - return ret; - } - - ret = sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_MIN_FREQ, min, - strlen(min)); - if (ret) - return ret; - - if (!write_max_first) { - ret = sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_MAX_FREQ, - max, strlen(max)); - if (ret) - return ret; - } - - return sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_GOVERNOR, - gov, strlen(gov)); -} - -int sysfs_set_frequency(unsigned int cpu, unsigned long target_frequency) -{ - struct cpufreq_policy *pol = sysfs_get_freq_policy(cpu); - char userspace_gov[] = "userspace"; - char freq[SYSFS_PATH_MAX]; - int ret; - - if (!pol) - return -ENODEV; - - if (strncmp(pol->governor, userspace_gov, 9) != 0) { - ret = sysfs_modify_freq_policy_governor(cpu, userspace_gov); - if (ret) { - cpufreq_put_policy(pol); - return ret; - } - } - - cpufreq_put_policy(pol); - - snprintf(freq, SYSFS_PATH_MAX, "%lu", target_frequency); - - return sysfs_cpufreq_write_one_value(cpu, WRITE_SCALING_SET_SPEED, - freq, strlen(freq)); -} - -/* CPUFREQ sysfs access **************************************************/ - -/* General sysfs access **************************************************/ -int sysfs_cpu_exists(unsigned int cpu) -{ - char file[SYSFS_PATH_MAX]; - struct stat statbuf; - - snprintf(file, SYSFS_PATH_MAX, PATH_TO_CPU "cpu%u/", cpu); - - if (stat(file, &statbuf) != 0) - return -ENOSYS; - - return S_ISDIR(statbuf.st_mode) ? 0 : -ENOSYS; -} - -/* General sysfs access **************************************************/ |