tools/thermal: Introduce tmon, a tool for thermal subsystem

Increasingly, Linux is running on thermally constrained devices. The simple
thermal relationship between processor and fan has become past for modern
computers.

As hardware vendors cope with the thermal constraints on their products,
more sensors are added, new cooling capabilities are introduced. The
complexity of the thermal relationship can grow exponentially among cooling
devices, zones, sensors, and trip points. They can also change dynamically.

To expose such relationship to the userspace, Linux generic thermal layer
introduced sysfs entry at /sys/class/thermal with a matrix of symbolic
links, trip point bindings, and device instances. To traverse such
matrix by hand is not a trivial task. Testing is also difficult in that
thermal conditions are often exception cases that hard to reach in
normal operations.

TMON is conceived as a tool to help visualize, tune, and test the
complex thermal subsystem.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

1 files changed, 596 insertions, 0 deletions

diff --git a/tools/thermal/tmon/sysfs.c b/tools/thermal/tmon/sysfs.c
new file mode 100644
index 000000000000..dfe454855cd2
--- /dev/null
+++ b/tools/thermal/tmon/sysfs.c
@@ -0,0 +1,596 @@
+/*
+ * sysfs.c sysfs ABI access functions for TMON program
+ *
+ * Copyright (C) 2013 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 or later as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Author: Jacob Pan <jacob.jun.pan@linux.intel.com>
+ *
+ */
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <dirent.h>
+#include <libintl.h>
+#include <ctype.h>
+#include <time.h>
+#include <syslog.h>
+#include <sys/time.h>
+#include <errno.h>
+
+#include "tmon.h"
+
+struct tmon_platform_data ptdata;
+const char *trip_type_name[] = {
+	"critical",
+	"hot",
+	"passive",
+	"active",
+};
+
+int sysfs_set_ulong(char *path, char *filename, unsigned long val)
+{
+	FILE *fd;
+	int ret = -1;
+	char filepath[256];
+
+	snprintf(filepath, 256, "%s/%s", path, filename);
+
+	fd = fopen(filepath, "w");
+	if (!fd) {
+		syslog(LOG_ERR, "Err: open %s: %s\n", __func__, filepath);
+		return ret;
+	}
+	ret = fprintf(fd, "%lu", val);
+	fclose(fd);
+
+	return 0;
+}
+
+/* history of thermal data, used for control algo */
+#define NR_THERMAL_RECORDS 3
+struct thermal_data_record trec[NR_THERMAL_RECORDS];
+int cur_thermal_record; /* index to the trec array */
+
+static int sysfs_get_ulong(char *path, char *filename, unsigned long *p_ulong)
+{
+	FILE *fd;
+	int ret = -1;
+	char filepath[256];
+
+	snprintf(filepath, 256, "%s/%s", path, filename);
+
+	fd = fopen(filepath, "r");
+	if (!fd) {
+		syslog(LOG_ERR, "Err: open %s: %s\n", __func__, filepath);
+		return ret;
+	}
+	ret = fscanf(fd, "%lu", p_ulong);
+	fclose(fd);
+
+	return 0;
+}
+
+static int sysfs_get_string(char *path, char *filename, char *str)
+{
+	FILE *fd;
+	int ret = -1;
+	char filepath[256];
+
+	snprintf(filepath, 256, "%s/%s", path, filename);
+
+	fd = fopen(filepath, "r");
+	if (!fd) {
+		syslog(LOG_ERR, "Err: open %s: %s\n", __func__, filepath);
+		return ret;
+	}
+	ret = fscanf(fd, "%256s", str);
+	fclose(fd);
+
+	return ret;
+}
+
+/* get states of the cooling device instance */
+static int probe_cdev(struct cdev_info *cdi, char *path)
+{
+	sysfs_get_string(path, "type", cdi->type);
+	sysfs_get_ulong(path, "max_state",  &cdi->max_state);
+	sysfs_get_ulong(path, "cur_state", &cdi->cur_state);
+
+	syslog(LOG_INFO, "%s: %s: type %s, max %lu, curr %lu inst %d\n",
+		__func__, path,
+		cdi->type, cdi->max_state, cdi->cur_state, cdi->instance);
+
+	return 0;
+}
+
+static int str_to_trip_type(char *name)
+{
+	int i;
+
+	for (i = 0; i < NR_THERMAL_TRIP_TYPE; i++) {
+		if (!strcmp(name, trip_type_name[i]))
+			return i;
+	}
+
+	return -ENOENT;
+}
+
+/* scan and fill in trip point info for a thermal zone and trip point id */
+static int get_trip_point_data(char *tz_path, int tzid, int tpid)
+{
+	char filename[256];
+	char temp_str[256];
+	int trip_type;
+
+	if (tpid >= MAX_NR_TRIP)
+		return -EINVAL;
+	/* check trip point type */
+	snprintf(filename, sizeof(filename), "trip_point_%d_type", tpid);
+	sysfs_get_string(tz_path, filename, temp_str);
+	trip_type = str_to_trip_type(temp_str);
+	if (trip_type < 0) {
+		syslog(LOG_ERR, "%s:%s no matching type\n", __func__, temp_str);
+		return -ENOENT;
+	}
+	ptdata.tzi[tzid].tp[tpid].type = trip_type;
+	syslog(LOG_INFO, "%s:tz:%d tp:%d:type:%s type id %d\n", __func__, tzid,
+		tpid, temp_str, trip_type);
+
+	/* TODO: check attribute */
+
+	return 0;
+}
+
+/* return instance id for file format such as trip_point_4_temp */
+static int get_instance_id(char *name, int pos, int skip)
+{
+	char *ch;
+	int i = 0;
+
+	ch = strtok(name, "_");
+	while (ch != NULL) {
+		++i;
+		syslog(LOG_INFO, "%s:%s:%s:%d", __func__, name, ch, i);
+		ch = strtok(NULL, "_");
+		if (pos == i)
+			return atol(ch + skip);
+	}
+
+	return -1;
+}
+
+/* Find trip point info of a thermal zone */
+static int find_tzone_tp(char *tz_name, char *d_name, struct tz_info *tzi,
+			int tz_id)
+{
+	int tp_id;
+	unsigned long temp_ulong;
+
+	if (strstr(d_name, "trip_point") &&
+		strstr(d_name, "temp")) {
+		/* check if trip point temp is non-zero
+		 * ignore 0/invalid trip points
+		 */
+		sysfs_get_ulong(tz_name, d_name, &temp_ulong);
+		if (temp_ulong < MAX_TEMP_KC) {
+			tzi->nr_trip_pts++;
+			/* found a valid trip point */
+			tp_id = get_instance_id(d_name, 2, 0);
+			syslog(LOG_DEBUG, "tzone %s trip %d temp %lu tpnode %s",
+				tz_name, tp_id, temp_ulong, d_name);
+			if (tp_id < 0 || tp_id >= MAX_NR_TRIP) {
+				syslog(LOG_ERR, "Failed to find TP inst %s\n",
+					d_name);
+				return -1;
+			}
+			get_trip_point_data(tz_name, tz_id, tp_id);
+			tzi->tp[tp_id].temp = temp_ulong;
+		}
+	}
+
+	return 0;
+}
+
+/* check cooling devices for binding info. */
+static int find_tzone_cdev(struct dirent *nl, char *tz_name,
+			struct tz_info *tzi, int tz_id, int cid)
+{
+	unsigned long trip_instance = 0;
+	char cdev_name_linked[256];
+	char cdev_name[256];
+	char cdev_trip_name[256];
+	int cdev_id;
+
+	if (nl->d_type == DT_LNK) {
+		syslog(LOG_DEBUG, "TZ%d: cdev: %s cid %d\n", tz_id, nl->d_name,
+			cid);
+		tzi->nr_cdev++;
+		if (tzi->nr_cdev > ptdata.nr_cooling_dev) {
+			syslog(LOG_ERR, "Err: Too many cdev? %d\n",
+				tzi->nr_cdev);
+			return -EINVAL;
+		}
+		/* find the link to real cooling device record binding */
+		snprintf(cdev_name, 256, "%s/%s", tz_name, nl->d_name);
+		memset(cdev_name_linked, 0, sizeof(cdev_name_linked));
+		if (readlink(cdev_name, cdev_name_linked,
+				sizeof(cdev_name_linked) - 1) != -1) {
+			cdev_id = get_instance_id(cdev_name_linked, 1,
+						sizeof("device") - 1);
+			syslog(LOG_DEBUG, "cdev %s linked to %s : %d\n",
+				cdev_name, cdev_name_linked, cdev_id);
+			tzi->cdev_binding |= (1 << cdev_id);
+
+			/* find the trip point in which the cdev is binded to
+			 * in this tzone
+			 */
+			snprintf(cdev_trip_name, 256, "%s%s", nl->d_name,
+				"_trip_point");
+			sysfs_get_ulong(tz_name, cdev_trip_name,
+					&trip_instance);
+			/* validate trip point range, e.g. trip could return -1
+			 * when passive is enabled
+			 */
+			if (trip_instance > MAX_NR_TRIP)
+				trip_instance = 0;
+			tzi->trip_binding[cdev_id] |= 1 << trip_instance;
+			syslog(LOG_DEBUG, "cdev %s -> trip:%lu: 0x%lx %d\n",
+				cdev_name, trip_instance,
+				tzi->trip_binding[cdev_id],
+				cdev_id);
+
+
+		}
+		return 0;
+	}
+
+	return -ENODEV;
+}
+
+
+
+/*****************************************************************************
+ * Before calling scan_tzones, thermal sysfs must be probed to determine
+ * the number of thermal zones and cooling devices.
+ * We loop through each thermal zone and fill in tz_info struct, i.e.
+ * ptdata.tzi[]
+root@jacob-chiefriver:~# tree -d /sys/class/thermal/thermal_zone0
+/sys/class/thermal/thermal_zone0
+|-- cdev0 -> ../cooling_device4
+|-- cdev1 -> ../cooling_device3
+|-- cdev10 -> ../cooling_device7
+|-- cdev11 -> ../cooling_device6
+|-- cdev12 -> ../cooling_device5
+|-- cdev2 -> ../cooling_device2
+|-- cdev3 -> ../cooling_device1
+|-- cdev4 -> ../cooling_device0
+|-- cdev5 -> ../cooling_device12
+|-- cdev6 -> ../cooling_device11
+|-- cdev7 -> ../cooling_device10
+|-- cdev8 -> ../cooling_device9
+|-- cdev9 -> ../cooling_device8
+|-- device -> ../../../LNXSYSTM:00/device:62/LNXTHERM:00
+|-- power
+`-- subsystem -> ../../../../class/thermal
+*****************************************************************************/
+static int scan_tzones(void)
+{
+	DIR *dir;
+	struct dirent **namelist;
+	char tz_name[256];
+	int i, j, n, k = 0;
+
+	if (!ptdata.nr_tz_sensor)
+		return -1;
+
+	for (i = 0; i <= ptdata.max_tz_instance; i++) {
+		memset(tz_name, 0, sizeof(tz_name));
+		snprintf(tz_name, 256, "%s/%s%d", THERMAL_SYSFS, TZONE, i);
+
+		dir = opendir(tz_name);
+		if (!dir) {
+			syslog(LOG_INFO, "Thermal zone %s skipped\n", tz_name);
+			continue;
+		}
+		/* keep track of valid tzones */
+		n = scandir(tz_name, &namelist, 0, alphasort);
+		if (n < 0)
+			syslog(LOG_ERR, "scandir failed in %s",  tz_name);
+		else {
+			sysfs_get_string(tz_name, "type", ptdata.tzi[k].type);
+			ptdata.tzi[k].instance = i;
+			/* detect trip points and cdev attached to this tzone */
+			j = 0; /* index for cdev */
+			ptdata.tzi[k].nr_cdev = 0;
+			ptdata.tzi[k].nr_trip_pts = 0;
+			while (n--) {
+				char *temp_str;
+
+				if (find_tzone_tp(tz_name, namelist[n]->d_name,
+							&ptdata.tzi[k], k))
+					break;
+				temp_str = strstr(namelist[n]->d_name, "cdev");
+				if (!temp_str) {
+					free(namelist[n]);
+					continue;
+				}
+				if (!find_tzone_cdev(namelist[n], tz_name,
+							&ptdata.tzi[k], i, j))
+					j++; /* increment cdev index */
+				free(namelist[n]);
+			}
+			free(namelist);
+		}
+		/*TODO: reverse trip points */
+		closedir(dir);
+		syslog(LOG_INFO, "TZ %d has %d cdev\n",	i,
+			ptdata.tzi[k].nr_cdev);
+		k++;
+	}
+
+	return 0;
+}
+
+static int scan_cdevs(void)
+{
+	DIR *dir;
+	struct dirent **namelist;
+	char cdev_name[256];
+	int i, n, k = 0;
+
+	if (!ptdata.nr_cooling_dev) {
+		fprintf(stderr, "No cooling devices found\n");
+		return 0;
+	}
+	for (i = 0; i <= ptdata.max_cdev_instance; i++) {
+		memset(cdev_name, 0, sizeof(cdev_name));
+		snprintf(cdev_name, 256, "%s/%s%d", THERMAL_SYSFS, CDEV, i);
+
+		dir = opendir(cdev_name);
+		if (!dir) {
+			syslog(LOG_INFO, "Cooling dev %s skipped\n", cdev_name);
+			/* there is a gap in cooling device id, check again
+			 * for the same index.
+			 */
+			continue;
+		}
+
+		n = scandir(cdev_name, &namelist, 0, alphasort);
+		if (n < 0)
+			syslog(LOG_ERR, "scandir failed in %s",  cdev_name);
+		else {
+			sysfs_get_string(cdev_name, "type", ptdata.cdi[k].type);
+			ptdata.cdi[k].instance = i;
+			if (strstr(ptdata.cdi[k].type, ctrl_cdev)) {
+				ptdata.cdi[k].flag |= CDEV_FLAG_IN_CONTROL;
+				syslog(LOG_DEBUG, "control cdev id %d\n", i);
+			}
+			while (n--)
+				free(namelist[n]);
+			free(namelist);
+		}
+		closedir(dir);
+		k++;
+	}
+	return 0;
+}
+
+
+int probe_thermal_sysfs(void)
+{
+	DIR *dir;
+	struct dirent **namelist;
+	int n;
+
+	dir = opendir(THERMAL_SYSFS);
+	if (!dir) {
+		fprintf(stderr, "\nNo thermal sysfs, exit\n");
+		return -1;
+	}
+	n = scandir(THERMAL_SYSFS, &namelist, 0, alphasort);
+	if (n < 0)
+		syslog(LOG_ERR, "scandir failed in thermal sysfs");
+	else {
+		/* detect number of thermal zones and cooling devices */
+		while (n--) {
+			int inst;
+
+			if (strstr(namelist[n]->d_name, CDEV)) {
+				inst = get_instance_id(namelist[n]->d_name, 1,
+						sizeof("device") - 1);
+				/* keep track of the max cooling device since
+				 * there may be gaps.
+				 */
+				if (inst > ptdata.max_cdev_instance)
+					ptdata.max_cdev_instance = inst;
+
+				syslog(LOG_DEBUG, "found cdev: %s %d %d\n",
+					namelist[n]->d_name,
+					ptdata.nr_cooling_dev,
+					ptdata.max_cdev_instance);
+				ptdata.nr_cooling_dev++;
+			} else if (strstr(namelist[n]->d_name, TZONE)) {
+				inst = get_instance_id(namelist[n]->d_name, 1,
+						sizeof("zone") - 1);
+				if (inst > ptdata.max_tz_instance)
+					ptdata.max_tz_instance = inst;
+
+				syslog(LOG_DEBUG, "found tzone: %s %d %d\n",
+					namelist[n]->d_name,
+					ptdata.nr_tz_sensor,
+					ptdata.max_tz_instance);
+				ptdata.nr_tz_sensor++;
+			}
+			free(namelist[n]);
+		}
+		free(namelist);
+	}
+	syslog(LOG_INFO, "found %d tzone(s), %d cdev(s), target zone %d\n",
+		ptdata.nr_tz_sensor, ptdata.nr_cooling_dev,
+		target_thermal_zone);
+	closedir(dir);
+
+	if (!ptdata.nr_tz_sensor) {
+		fprintf(stderr, "\nNo thermal zones found, exit\n\n");
+		return -1;
+	}
+
+	ptdata.tzi = calloc(sizeof(struct tz_info), ptdata.max_tz_instance+1);
+	if (!ptdata.tzi) {
+		fprintf(stderr, "Err: allocate tz_info\n");
+		return -1;
+	}
+
+	/* we still show thermal zone information if there is no cdev */
+	if (ptdata.nr_cooling_dev) {
+		ptdata.cdi = calloc(sizeof(struct cdev_info),
+				ptdata.max_cdev_instance + 1);
+		if (!ptdata.cdi) {
+			free(ptdata.tzi);
+			fprintf(stderr, "Err: allocate cdev_info\n");
+			return -1;
+		}
+	}
+
+	/* now probe tzones */
+	if (scan_tzones())
+		return -1;
+	if (scan_cdevs())
+		return -1;
+	return 0;
+}
+
+/* convert sysfs zone instance to zone array index */
+int zone_instance_to_index(int zone_inst)
+{
+	int i;
+
+	for (i = 0; i < ptdata.nr_tz_sensor; i++)
+		if (ptdata.tzi[i].instance == zone_inst)
+			return i;
+	return -ENOENT;
+}
+
+/* read temperature of all thermal zones */
+int update_thermal_data()
+{
+	int i;
+	char tz_name[256];
+	static unsigned long samples;
+
+	if (!ptdata.nr_tz_sensor) {
+		syslog(LOG_ERR, "No thermal zones found!\n");
+		return -1;
+	}
+
+	/* circular buffer for keeping historic data */
+	if (cur_thermal_record >= NR_THERMAL_RECORDS)
+		cur_thermal_record = 0;
+	gettimeofday(&trec[cur_thermal_record].tv, NULL);
+	if (tmon_log) {
+		fprintf(tmon_log, "%lu ", ++samples);
+		fprintf(tmon_log, "%3.1f ", p_param.t_target);
+	}
+	for (i = 0; i < ptdata.nr_tz_sensor; i++) {
+		memset(tz_name, 0, sizeof(tz_name));
+		snprintf(tz_name, 256, "%s/%s%d", THERMAL_SYSFS, TZONE,
+			ptdata.tzi[i].instance);
+		sysfs_get_ulong(tz_name, "temp",
+				&trec[cur_thermal_record].temp[i]);
+		if (tmon_log)
+			fprintf(tmon_log, "%lu ",
+				trec[cur_thermal_record].temp[i]/1000);
+	}
+	for (i = 0; i < ptdata.nr_cooling_dev; i++) {
+		char cdev_name[256];
+		unsigned long val;
+
+		snprintf(cdev_name, 256, "%s/%s%d", THERMAL_SYSFS, CDEV,
+			ptdata.cdi[i].instance);
+		probe_cdev(&ptdata.cdi[i], cdev_name);
+		val = ptdata.cdi[i].cur_state;
+		if (val > 1000000)
+			val = 0;
+		if (tmon_log)
+			fprintf(tmon_log, "%lu ", val);
+	}
+
+	if (tmon_log) {
+		fprintf(tmon_log, "\n");
+		fflush(tmon_log);
+	}
+
+	return 0;
+}
+
+void set_ctrl_state(unsigned long state)
+{
+	char ctrl_cdev_path[256];
+	int i;
+	unsigned long cdev_state;
+
+	if (no_control)
+		return;
+	/* set all ctrl cdev to the same state */
+	for (i = 0; i < ptdata.nr_cooling_dev; i++) {
+		if (ptdata.cdi[i].flag & CDEV_FLAG_IN_CONTROL) {
+			if (ptdata.cdi[i].max_state < 10) {
+				strcpy(ctrl_cdev, "None.");
+				return;
+			}
+			/* scale to percentage of max_state */
+			cdev_state = state * ptdata.cdi[i].max_state/100;
+			syslog(LOG_DEBUG,
+				"ctrl cdev %d set state %lu scaled to %lu\n",
+				ptdata.cdi[i].instance, state, cdev_state);
+			snprintf(ctrl_cdev_path, 256, "%s/%s%d", THERMAL_SYSFS,
+				CDEV, ptdata.cdi[i].instance);
+			syslog(LOG_DEBUG, "ctrl cdev path %s", ctrl_cdev_path);
+			sysfs_set_ulong(ctrl_cdev_path, "cur_state",
+					cdev_state);
+		}
+	}
+}
+
+void get_ctrl_state(unsigned long *state)
+{
+	char ctrl_cdev_path[256];
+	int ctrl_cdev_id = -1;
+	int i;
+
+	/* TODO: take average of all ctrl types. also consider change based on
+	 * uevent. Take the first reading for now.
+	 */
+	for (i = 0; i < ptdata.nr_cooling_dev; i++) {
+		if (ptdata.cdi[i].flag & CDEV_FLAG_IN_CONTROL) {
+			ctrl_cdev_id = ptdata.cdi[i].instance;
+			syslog(LOG_INFO, "ctrl cdev %d get state\n",
+				ptdata.cdi[i].instance);
+			break;
+		}
+	}
+	if (ctrl_cdev_id == -1) {
+		*state = 0;
+		return;
+	}
+	snprintf(ctrl_cdev_path, 256, "%s/%s%d", THERMAL_SYSFS,
+		CDEV, ctrl_cdev_id);
+	sysfs_get_ulong(ctrl_cdev_path, "cur_state", state);
+}
+
+void free_thermal_data(void)
+{
+	free(ptdata.tzi);
+	free(ptdata.cdi);
+}