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Diffstat (limited to 'tools/power/cpupower/lib/sysfs.c')
-rw-r--r--tools/power/cpupower/lib/sysfs.c672
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", &current->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", &current->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",
- &current->frequency,
- &current->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 **************************************************/