grover/envd/piclenvd.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2000 by Sun Microsystems, Inc.
 * All rights reserved.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * This file contains the environmental daemon module.
 */


/*
 * Grover system contains one temperature device, MAX1617, which consists
 * of two sensors: CPU die and CPU ambient. Each sensor is represented
 * as a different minor device and the current temperature is read via an
 * I2C_GET_TEMPERATURE ioctl call to the max1617 driver. Additionally, the
 * MAX1617 device supports both a low and high temperature limit, which
 * can trigger an alert condition, causing power supply to turn off.
 *
 * The environmental daemon defines the following thresholds per sensor:
 *
 *  high_power_off      high hard shutdown
 *  high_shutdown       high soft shutdown limit
 *  high_warning        high warning limit
 *  low_warning     low warning limit
 *  low_shutdown        low soft shutdown limit
 *  low_power_off       low hard shutdown limit
 *
 * Except for the low_power_off and high_power_off limits, all other threshold
 * values can be changed via "piclenvd.conf" configuration file.
 *
 * Environmental monitoring is done by the "envthr" thread. It periodically
 * monitors both CPU die and CPU ambient temperatures and takes appropriate
 * action depending upon the current temperature and threshold values for
 * that sensor. If the temperature reaches the high_shutdown limit or the
 * low_shutdown limit, and remains there for over shutdown_interval seconds,
 * it forces a graceful system shutdown via tuneable shutdown_cmd string
 * variable. Otherwise, if the temperature reaches the high_warning limit
 * or the low_warning limit, it logs and prints a message on the console.
 * This message will be printed at most at "warning_interval" seconds
 * interval, which is also a tuneable variable.
 *
 * Grover system also contains a fan, known as system fan, which can be turned
 * ON or OFF under software control. However, its speed is automatically
 * controlled by the hardware based upon the ambient temperature. When in EStar
 * mode (i.e. lowest power state), the environmental daemon will turn off this
 * fan provided the CPU die and ambient temperature is below the high warning
 * limits.
 *
 * The power state monitoring is done by the "pmthr" thread. It uses the
 * PM_GET_STATE_CHANGE and PM_GET_STATE_CHANGE_WAIT ioctl commands to pick
 * up any power state change events. It processes all queued power state
 * change events and determines the curret lowest power state and saves it
 * in cur_lpstate variable. Whenever this state changes from the previous
 * lowest power state (saved in prev_lpstate), it wakes up the "envtrh"
 * thread.
 *
 * The "lpstate_lock" mutex and "lpstate_cond" condition variables are used
 * to communicate power state change events from the "pmthr" to the "envthr"
 * thread.  The "envthr" thread uses the pthread_cond_timedwait() interface
 * to wait for any power state change notifications. The "pmthr" uses the
 * pthread_signal() interface to wake up the "envthr" thread.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <limits.h>
#include <syslog.h>
#include <errno.h>
#include <fcntl.h>
#include <picl.h>
#include <picltree.h>
#include <pthread.h>
#include <sys/pm.h>
#include <sys/open.h>
#include <sys/time.h>
#include <sys/utsname.h>
#include <sys/systeminfo.h>
#include <sys/i2c/clients/max1617.h>
#include <sys/i2c/clients/i2c_client.h>
#include "envd.h"


/*
 * PICL plguin
 */
static void piclenvd_register(void);
static void piclenvd_init(void);
static void piclenvd_fini(void);
extern void env_picl_setup();

#pragma init(piclenvd_register)

static picld_plugin_reg_t  my_reg_info = {
    PICLD_PLUGIN_VERSION_1,
    PICLD_PLUGIN_CRITICAL,
    "SUNW_piclenvd",
    piclenvd_init,
    piclenvd_fini,
};

/*
 * tuneable variables
 */
int     env_debug;
static int  sensor_poll_interval = SENSOR_POLL_INTERVAL;
static int  warning_interval = WARNING_INTERVAL;
static int  shutdown_interval = SHUTDOWN_INTERVAL;
static char shutdown_cmd[128] = SHUTDOWN_CMD;
static int  monitor_temperature = 0;

static sensor_thresh_t cpu_die_thresh = {
    CPU_DIE_LOW_POWER_OFF, CPU_DIE_HIGH_POWER_OFF,
    CPU_DIE_LOW_SHUTDOWN, CPU_DIE_HIGH_SHUTDOWN,
    CPU_DIE_LOW_WARNING, CPU_DIE_HIGH_WARNING,
    CPU_DIE_TARGET_TEMP
};

static sensor_thresh_t cpu_amb_thresh = {
    CPU_AMB_LOW_POWER_OFF, CPU_AMB_HIGH_POWER_OFF,
    CPU_AMB_LOW_SHUTDOWN, CPU_AMB_HIGH_SHUTDOWN,
    CPU_AMB_LOW_WARNING, CPU_AMB_HIGH_WARNING,
    CPU_AMB_TARGET_TEMP
};

/*
 * Temperature sensors
 */

static env_sensor_t cpu_die_sensor =
    { SENSOR_CPU_DIE, CPU_DIE_SENSOR_DEVFS, &cpu_die_thresh};

static env_sensor_t cpu_amb_sensor =
    { SENSOR_CPU_AMB, CPU_AMB_SENSOR_DEVFS, &cpu_amb_thresh};


static env_sensor_t *envd_sensors[] = {
    &cpu_die_sensor,
    &cpu_amb_sensor,
    NULL
};

/*
 * Fan devices
 */
static env_fan_t envd_system_fan = {
    ENV_SYSTEM_FAN, ENV_SYSTEM_FAN_DEVFS,
    SYSTEM_FAN_SPEED_MIN, SYSTEM_FAN_SPEED_MAX,
};

static env_fan_t *envd_fans[] =  {
    &envd_system_fan,
    NULL
};


/*
 * Environmental thread variables
 */
static boolean_t    envd_inited = B_FALSE;
static boolean_t    system_shutdown_started;
static boolean_t    envthr_created;     /* envthr created */
static pthread_t    envthr_tid;     /* envthr thread ID */
static pthread_attr_t   thr_attr;

/*
 * Power management thread (pmthr) variables
 */
static pthread_t    pmthr_tid;      /* pmthr thread ID */
static int      pmthr_created;      /* pmthr created */
static int      pm_fd;          /* PM device file descriptor */
static int      cur_lpstate;        /* cur low power state */

static pthread_mutex_t  lpstate_lock;       /* low power state lock */
static pthread_cond_t   lpstate_cond;       /* low power state condvar */


/*
 * Tuneable variables data structure/array
 */

typedef struct {
    char    *name;      /* keyword */
    void    *addr;      /* memory (variable) address */
    int type;       /* keyword type */
    int size;       /* variable size */
} env_tuneable_t;

/* keyword types */
#define KTYPE_INT   1   /* signed int */
#define KTYPE_STRING    2   /* string in double quotes */

static env_tuneable_t env_tuneables[] = {
    {"cpu_amb_low_shutdown", &cpu_amb_thresh.low_shutdown, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_amb_low_warning", &cpu_amb_thresh.low_warning, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_amb_target_temp", &cpu_amb_thresh.target_temp, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_amb_high_shutdown", &cpu_amb_thresh.high_shutdown, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_amb_high_warning", &cpu_amb_thresh.high_warning, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_die_low_shutdown", &cpu_die_thresh.low_shutdown, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_die_low_warning", &cpu_die_thresh.low_warning, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_die_target_temp", &cpu_die_thresh.target_temp, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_die_high_shutdown", &cpu_die_thresh.high_shutdown, KTYPE_INT,
        sizeof (tempr_t)},
    {"cpu_die_high_warning", &cpu_die_thresh.high_warning, KTYPE_INT,
        sizeof (tempr_t)},
    {"sensor_poll_interval", &sensor_poll_interval, KTYPE_INT,
        sizeof (sensor_poll_interval)},
    {"monitor_temperature", &monitor_temperature, KTYPE_INT,
        sizeof (monitor_temperature)},
    {"warning_interval", &warning_interval, KTYPE_INT,
        sizeof (warning_interval)},
    {"shutdown_interval", &shutdown_interval, KTYPE_INT,
        sizeof (shutdown_interval)},
    {"shutdown_cmd", &shutdown_cmd[0], KTYPE_STRING, sizeof (shutdown_cmd)},
    {"env_debug", &env_debug, KTYPE_INT, sizeof (env_debug)},
    { NULL, NULL, 0, 0}
};

/*
 * Lookup fan and return a pointer to env_fan_t data structure.
 */
env_fan_t *
fan_lookup(char *name)
{
    int     i;
    env_fan_t   *fanp;

    for (i = 0; (fanp = envd_fans[i]) != NULL; i++) {
        if (strcmp(fanp->name, name) == 0)
            return (fanp);
    }
    return (NULL);
}

/*
 * Lookup sensor and return a pointer to env_sensor_t data structure.
 */
env_sensor_t *
sensor_lookup(char *name)
{
    int     i;
    env_sensor_t    *sensorp;

    for (i = 0; (sensorp = envd_sensors[i]) != NULL; i++) {
        if (strcmp(sensorp->name, name) == 0)
            return (sensorp);
    }
    return (NULL);
}

/*
 * Get current temperature
 * Returns -1 on error, 0 if successful
 */
int
get_temperature(env_sensor_t *sensorp, tempr_t *temp)
{
    int fd = sensorp->fd;
    int retval = 0;

    if (fd == -1)
        retval = -1;
    else if (ioctl(fd, I2C_GET_TEMPERATURE, temp) == -1) {
        retval = -1;
        if (sensorp->error == 0) {
            sensorp->error = 1;
            envd_log(LOG_WARNING, ENV_SENSOR_ACCESS_FAIL,
                sensorp->name, errno, strerror(errno));
        }
    } else if (sensorp->error != 0) {
        sensorp->error = 0;
        envd_log(LOG_WARNING, ENV_SENSOR_ACCESS_OK, sensorp->name);
    }

    return (retval);
}

/*
 * Get current fan speed
 * Returns -1 on error, 0 if successful
 */
int
get_fan_speed(env_fan_t *fanp, fanspeed_t *fanspeedp)
{
    int fan_fd;
    int retval = 0;

    fan_fd = fanp->fd;
    if (fan_fd == -1 || read(fan_fd, fanspeedp, sizeof (fanspeed_t)) !=
        sizeof (fanspeed_t))
        retval = -1;
    return (retval);
}

/*
 * Set fan speed
 * Returns -1 on error, 0 if successful
 */
static int
set_fan_speed(env_fan_t *fanp, fanspeed_t fanspeed)
{
    int fan_fd;
    int retval = 0;

    fan_fd = fanp->fd;
    if (fan_fd == -1 || write(fan_fd, &fanspeed, sizeof (fanspeed)) !=
        sizeof (fanspeed_t))
        retval = -1;
    return (retval);
}


/*
 * close all fan devices
 */
static void
envd_close_fans(void)
{
    int     i;
    env_fan_t   *fanp;

    for (i = 0; (fanp = envd_fans[i]) != NULL; i++) {
        if (fanp->fd != -1) {
            (void) close(fanp->fd);
            fanp->fd = -1;
        }
    }
}

/*
 * Close sensor devices
 */
static void
envd_close_sensors(void)
{
    int     i;
    env_sensor_t    *sensorp;

    for (i = 0; (sensorp = envd_sensors[i]) != NULL; i++) {
        if (sensorp->fd != -1) {
            (void) close(sensorp->fd);
            sensorp->fd = -1;
        }
    }
}

/*
 * Close PM device
 */
static void
envd_close_pm(void)
{
    if (pm_fd != -1) {
        (void) close(pm_fd);
        pm_fd = -1;
    }
}

/*
 * Open fan devices and initialize per fan data structure.
 * Returns #fans found.
 */
static int
envd_setup_fans(void)
{
    int     i, fd;
    fanspeed_t  speed;
    env_fan_t   *fanp;
    char        path[FILENAME_MAX];
    int     fancnt = 0;

    for (i = 0; (fanp = envd_fans[i]) != NULL; i++) {
        fanp->fd = -1;
        fanp->cur_speed = 0;
        fanp->prev_speed = 0;

        (void) strcpy(path, "/devices");
        (void) strlcat(path, fanp->devfs_path, sizeof (path));
        fd = open(path, O_RDWR);
        if (fd == -1) {
            envd_log(LOG_WARNING, ENV_FAN_OPEN_FAIL, fanp->name,
                fanp->devfs_path, errno, strerror(errno));
            fanp->present = B_FALSE;
            continue;
        }
        fanp->fd = fd;
        fanp->present = B_TRUE;
        fancnt++;

        /*
         * Set cur_speed/prev_speed to current fan speed
         */
        if (get_fan_speed(fanp, &speed) == -1) {
            /*
             * The Fan driver does not know the current fan speed.
             * Initialize it to 50% of the max speed and reread
             * to get the current speed.
             */
            speed = fanp->speed_max/2;
            (void) set_fan_speed(fanp, speed);
            if (get_fan_speed(fanp, &speed) == -1)
                continue;
        }
        fanp->cur_speed = speed;
        fanp->prev_speed = speed;
    }
    return (fancnt);
}

/*
 * Open temperature sensor devices and initialize per sensor data structure.
 * Returns #sensors found.
 */
static int
envd_setup_sensors(void)
{
    int     i;
    tempr_t     temp;
    env_sensor_t    *sensorp;
    char        path[FILENAME_MAX];
    int     sensorcnt = 0;
    sensor_thresh_t *threshp;

    for (i = 0; (sensorp = envd_sensors[i]) != NULL; i++) {
        sensorp->fd = -1;
        sensorp->shutdown_initiated = B_FALSE;
        sensorp->warning_tstamp = 0;
        sensorp->shutdown_tstamp = 0;
        threshp = sensorp->temp_thresh;
        sensorp->cur_temp = threshp->target_temp;
        sensorp->error = 0;

        (void) strcpy(path, "/devices");
        (void) strlcat(path, sensorp->devfs_path, sizeof (path));
        sensorp->fd = open(path, O_RDWR);
        if (sensorp->fd == -1) {
            envd_log(LOG_WARNING, ENV_SENSOR_OPEN_FAIL,
                sensorp->name, sensorp->devfs_path, errno,
                strerror(errno));
            sensorp->present = B_FALSE;
            continue;
        }
        sensorp->present = B_TRUE;
        sensorcnt++;

        if (monitor_temperature) {
            /*
             * Set low_power_off and high_power_off limits
             */
            (void) ioctl(sensorp->fd, MAX1617_SET_LOW_LIMIT,
                &threshp->low_power_off);
            (void) ioctl(sensorp->fd, MAX1617_SET_HIGH_LIMIT,
                &threshp->high_power_off);
        }

        /*
         * Set cur_temp field to the current temperature value
         */
        if (get_temperature(sensorp, &temp) == 0) {
            sensorp->cur_temp = temp;
        }
    }
    return (sensorcnt);
}

/*
 * Read all temperature sensors and take appropriate action based
 * upon temperature threshols associated with each sensor. Possible
 * actions are:
 *
 *  temperature > high_shutdown
 *  temperature < low_shutdown
 *      Gracefully shutdown the system and log/print a message
 *      on the system console provided the temperature has been
 *      in shutdown range for "shutdown_interval" seconds.
 *
 *  high_warning < temperature <= high_shutdown
 *  low_warning  > temperature >= low_shutdown
 *      Log/print a warning message on the system console at most
 *      once every "warning_interval" seconds.
 *
 * Note that the current temperature is recorded in the "cur_temp" field
 * within each env_sensor_t structure.
 */
static void
monitor_sensors(void)
{
    tempr_t     temp;
    int     i;
    env_sensor_t    *sensorp;
    sensor_thresh_t *threshp;
    struct timeval  ct;
    char        msgbuf[BUFSIZ];
    char        syscmd[BUFSIZ];

    for (i = 0; (sensorp = envd_sensors[i]) != NULL; i++) {
        if (get_temperature(sensorp, &temp) < 0)
            continue;

        sensorp->cur_temp = temp;

        if (env_debug)
            envd_log(LOG_INFO,
                "sensor: %-13s temp  cur:%3d  target:%3d\n",
                sensorp->name, temp,
                sensorp->temp_thresh->target_temp);

        if (!monitor_temperature)
            continue;

        /*
         * If this sensor already triggered system shutdown, don't
         * log any more shutdown/warning messages for it.
         */
        if (sensorp->shutdown_initiated)
            continue;

        /*
         * Check for the temperature in warning and shutdown range
         * and take appropriate action.
         */
        threshp = sensorp->temp_thresh;
        if (TEMP_IN_WARNING_RANGE(temp, threshp)) {
            /*
             * Log warning message at most once every
             * warning_interval seconds.
             */
            (void) gettimeofday(&ct, NULL);
            if ((ct.tv_sec - sensorp->warning_tstamp) >=
                warning_interval) {
                envd_log(LOG_WARNING, ENV_WARNING_MSG,
                    sensorp->name, temp,
                    threshp->low_warning,
                    threshp->high_warning);
                sensorp->warning_tstamp = ct.tv_sec;
            }
        }

        if (TEMP_IN_SHUTDOWN_RANGE(temp, threshp)) {
            (void) gettimeofday(&ct, NULL);
            if (sensorp->shutdown_tstamp == 0)
                sensorp->shutdown_tstamp = ct.tv_sec;

            /*
             * Shutdown the system if the temperature remains
             * in the shutdown range for over shutdown_interval
             * seconds.
             */
            if ((ct.tv_sec - sensorp->shutdown_tstamp) >=
                shutdown_interval) {
                /* log error */
                sensorp->shutdown_initiated = B_TRUE;
                (void) snprintf(msgbuf, sizeof (msgbuf),
                    ENV_SHUTDOWN_MSG, sensorp->name,
                    temp, threshp->low_shutdown,
                    threshp->high_shutdown);
                envd_log(LOG_CRIT, msgbuf);

                /* shutdown the system (only once) */
                if (system_shutdown_started == B_FALSE) {
                    (void) snprintf(syscmd, sizeof (syscmd),
                        "%s \"%s\"", shutdown_cmd, msgbuf);
                    envd_log(LOG_CRIT, syscmd);
                    system_shutdown_started = B_TRUE;
                    (void) system(syscmd);
                }
            }
        } else if (sensorp->shutdown_tstamp != 0)
            sensorp->shutdown_tstamp = 0;
    }
}


/*
 * This is the environment thread, which monitors the current temperature
 * and power managed state and controls system fan speed.  Temperature is
 * polled every sensor-poll_interval seconds duration.
 */
static void *
envthr(void *args)
{
    int     err;
    fanspeed_t  fan_speed;
    struct timeval  ct;
    struct timespec to;
    env_fan_t   *pmfanp = &envd_system_fan;
    tempr_t     cpu_amb_temp, cpu_die_temp;
    tempr_t     cpu_amb_warning, cpu_die_warning;

    (void) pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
    (void) pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);

    cpu_amb_warning = cpu_amb_sensor.temp_thresh->high_warning;
    cpu_die_warning = cpu_die_sensor.temp_thresh->high_warning;

    for (;;) {
        (void) gettimeofday(&ct, NULL);

        /*
         * Monitor current temperature for all sensors
         * (current temperature is recorded in the "cur_temp"
         * field within each sensor data structure)
         */
        monitor_sensors();

        cpu_amb_temp =  cpu_amb_sensor.cur_temp;
        cpu_die_temp =  cpu_die_sensor.cur_temp;

        /*
         * Process any PM state change events while waiting until
         * time to poll sensors again (i.e. sensor_poll_interval
         * seconds from the last time).
         */
        to.tv_sec = ct.tv_sec + sensor_poll_interval;
        to.tv_nsec = 0;
        for (;;) {
            /*
             * Turn off system fan if in lowest power state
             * and both CPU die and ambient temperatures are
             * below corresponding high warning temperatures.
             */
            fan_speed = pmfanp->speed_max;
            if (cur_lpstate && cpu_amb_temp < cpu_amb_warning &&
                cpu_die_temp < cpu_die_warning)
                fan_speed = pmfanp->speed_min;

            if (env_debug)
                envd_log(LOG_INFO,
                    "fan: %-16s speed cur:%3d  new:%3d "
                    "low-power:%d\n", pmfanp->name,
                    (uint_t)pmfanp->cur_speed,
                    (uint_t)fan_speed, cur_lpstate);

            if (fan_speed != pmfanp->cur_speed &&
                set_fan_speed(pmfanp, fan_speed) == 0)
                pmfanp->cur_speed = fan_speed;

            /* wait for power state change or time to poll */
            pthread_mutex_lock(&lpstate_lock);
            err = pthread_cond_timedwait(&lpstate_cond,
                &lpstate_lock, &to);
            pthread_mutex_unlock(&lpstate_lock);
            if (err == ETIMEDOUT)
                break;
        }
    }
    /*NOTREACHED*/
    return (NULL);
}

/*
 * This is the power management thread, which monitors all power state
 * change events and wakes up the "envthr" thread when the system enters
 * or exits the lowest power state.
 */
static void *
pmthr(void *args)
{
    pm_state_change_t   pmstate;
    char            physpath[PATH_MAX];
    int         prev_lpstate;

    (void) pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
    (void) pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);

    pmstate.physpath = physpath;
    pmstate.size = sizeof (physpath);
    cur_lpstate = 0;
    prev_lpstate = 0;

    for (;;) {
        /*
         * Get PM state change events to check if the system
         * is in lowest power state and wake up the "envthr"
         * thread when the power state changes.
         *
         * To minimize polling, we use the blocking interface
         * to get the power state change event here.
         */
        if (ioctl(pm_fd, PM_GET_STATE_CHANGE_WAIT, &pmstate) != 0) {
            if (errno != EINTR)
                break;
            continue;
        }

        /*
         * Extract the lowest power state from the last queued
         * state change events. We pick up queued state change
         * events using the non-blocking interface and wake up
         * the "envthr" thread only after consuming all the
         * state change events queued at that time.
         */
        do {
            if (env_debug > 1)  {
                envd_log(LOG_INFO,
                    "pmstate event:0x%x flags:%x comp:%d "
                    "oldval:%d newval:%d path:%s\n",
                    pmstate.event, pmstate.flags,
                    pmstate.component, pmstate.old_level,
                    pmstate.new_level, pmstate.physpath);
            }
            cur_lpstate =
                (pmstate.flags & PSC_ALL_LOWEST) ? 1 : 0;
        } while (ioctl(pm_fd, PM_GET_STATE_CHANGE, &pmstate) == 0);

        if (cur_lpstate != prev_lpstate) {
            prev_lpstate = cur_lpstate;
            pthread_mutex_lock(&lpstate_lock);
            pthread_cond_signal(&lpstate_cond);
            pthread_mutex_unlock(&lpstate_lock);
        }
    }

    /*
     * We won't be able to monitor lowest power state any longer,
     * hence reset it and wakeup the "envthr".
     */
    if (cur_lpstate != 0) {
        prev_lpstate = cur_lpstate;
        cur_lpstate = 0;
        pthread_mutex_lock(&lpstate_lock);
        pthread_cond_signal(&lpstate_cond);
        pthread_mutex_unlock(&lpstate_lock);
    }
    envd_log(LOG_ERR, PM_THREAD_EXITING, errno, strerror(errno));
    return (NULL);
}


/*
 * Parse string value (handling escaped double quotes and other characters)
 * and return string end pointer.
 */

static char *
parse_string_val(char *buf)
{
    char    *p, c;

    if (buf[0] != '"')
        return (NULL);

    for (p = buf+1; (c = *p) != '\0'; p++)
        if (c == '"' || (c == '\\' && *++p == '\0'))
            break;

    return ((*p == '"') ? p : NULL);
}


/*
 * Process configuration file
 */
static void
process_env_conf_file(void)
{
    int     line, len, val, toklen;
    char        buf[BUFSIZ];
    FILE        *fp;
    env_tuneable_t  *tunep;
    char        nmbuf[SYS_NMLN];
    char        fname[PATH_MAX];
    char        *tok, *valuep, *strend;
    char        tokdel[] = " \t\n\r";
    int     skip_line = 0;

    if (sysinfo(SI_PLATFORM, nmbuf, sizeof (nmbuf)) == -1)
        return;

    (void) snprintf(fname, sizeof (fname), PICLD_PLAT_PLUGIN_DIRF, nmbuf);
    (void) strlcat(fname, ENV_CONF_FILE, sizeof (fname));
    fp = fopen(fname, "r");
    if (fp == NULL)
        return;

    /*
     * Blank lines or lines starting with "#" or "*" in the first
     * column are ignored. All other lines are assumed to contain
     * input in the following format:
     *
     *  keyword value
     *
     * where the "value" can be a signed integer or string (in
     * double quotes) depending upon the keyword.
     */

    for (line = 1; fgets(buf, sizeof (buf), fp) != NULL; line++) {
        len = strlen(buf);
        if (len <= 0)
            continue;

        /* skip long lines */
        if (buf[len-1] != '\n') {
            skip_line = 1;
            continue;
        } else if (skip_line) {
            skip_line = 0;
            continue;
        } else
            buf[len-1] = '\0';

        /* skip comments */
        if (buf[0] == '*' || buf[0] == '#')
            continue;

        /*
         * Skip over white space to get the keyword
         */
        tok = buf + strspn(buf, tokdel);
        if (*tok == '\0')
            continue;           /* blank line */

        toklen = strcspn(tok, tokdel);
        tok[toklen] = '\0';

        /* Get possible location for value (within current line) */
        valuep = tok + toklen + 1;
        if (valuep > buf+len)
            valuep = buf + len;

        /*
         * Lookup the keyword and process value accordingly
         */
        for (tunep = &env_tuneables[0]; tunep->name != NULL; tunep++) {
            if (strcmp(tunep->name, tok) != 0)
                continue;

            switch (tunep->type) {
            case KTYPE_INT:
                errno = 0;
                val = strtol(valuep, &valuep, 0);

                /* Check for invalid value or extra tokens */
                if (errno != 0 || strtok(valuep, tokdel)) {
                    envd_log(LOG_INFO,
                        ENV_CONF_INT_EXPECTED,
                        fname, line, tok);
                    break;
                }

                /* Update only if value within range */
                if (tunep->size == sizeof (int8_t) &&
                    val == (int8_t)val)
                    *(int8_t *)tunep->addr = (int8_t)val;
                else if (tunep->size == sizeof (short) &&
                    val == (short)val)
                    *(short *)tunep->addr = (short)val;
                else if (tunep->size == sizeof (int))
                    *(int *)tunep->addr = (int)val;
                else {
                    envd_log(LOG_INFO,
                        ENV_CONF_INT_EXPECTED,
                        fname, line, tok);
                    break;
                }
                if (env_debug)
                    envd_log(LOG_INFO, "SUNW_piclenvd: "
                        "file:%s line:%d %s = %d\n",
                        fname, line, tok, val);
                break;

            case KTYPE_STRING:
                /*
                 * String value must be within double quotes.
                 * Skip over initial white spaces before
                 * looking for value.
                 */
                valuep += strspn(valuep, tokdel);
                strend = parse_string_val(valuep);

                if (strend == NULL || *valuep != '"' ||
                    strtok(strend+1, tokdel) != NULL ||
                    (strend-valuep) > tunep->size) {
                    envd_log(LOG_INFO,
                        ENV_CONF_STRING_EXPECTED,
                        fname, line, tok,
                        tunep->size);
                    break;
                }
                *strend = '\0';
                if (env_debug)
                    envd_log(LOG_INFO, "piclenvd: file:%s"
                        " line:%d %s = \"%s\"\n",
                        fname, line, tok, valuep+1);
                (void) strcpy(tunep->addr, (caddr_t)valuep+1);
                break;

            default:
                envd_log(LOG_INFO,
                    ENV_CONF_UNSUPPORTED_TYPE,
                    fname, line,
                    tunep->type, tunep->name);
            }
            break;
        }

        if (tunep->name == NULL)
            envd_log(LOG_INFO, ENV_CONF_UNSUPPORTED_KEYWORD,
                fname, line, tok);
    }
    (void) fclose(fp);
}

/*
 * Setup envrionmental daemon state and start threads to monitor
 * temperature and power management state.
 * Returns -1 on error, 0 if successful.
 */

static int
envd_setup(void)
{
    if (envd_inited == B_FALSE) {
        /*
         * Initialize global state
         */
        system_shutdown_started = B_FALSE;
        envthr_created = B_FALSE;
        pmthr_created = B_FALSE;

        if (pthread_attr_init(&thr_attr) != 0 ||
            pthread_attr_setscope(&thr_attr, PTHREAD_SCOPE_SYSTEM) != 0)
            return (-1);

        if (pthread_mutex_init(&lpstate_lock, NULL) != 0 ||
            pthread_cond_init(&lpstate_cond, NULL) != 0)
            return (-1);

        /*
         * Process tuneable parameters
         */
        process_env_conf_file();

        /*
         * Setup temperature sensors and fail if we can't open
         * at least one sensor.
         */
        if (envd_setup_sensors() <= 0)
            return (-1);

        /*
         * Setup fan device (don't fail even if we can't access
         * the fan as we can still monitor temeperature.
         */
        (void) envd_setup_fans();

        /*
         * Create a thread to monitor temperature and control fan
         * speed.
         */
        if (envthr_created == B_FALSE && pthread_create(&envthr_tid,
            &thr_attr, envthr, (void *)NULL) != 0) {
            envd_close_fans();
            envd_close_sensors();
            envd_log(LOG_CRIT, ENV_THREAD_CREATE_FAILED);
            return (-1);
        }
        envthr_created = B_TRUE;
    }
    envd_inited = B_TRUE;

    /*
     * Create a thread to monitor PM state
     */
    if (pmthr_created == B_FALSE) {
        pm_fd = open(PM_DEVICE, O_RDONLY);
        if (pm_fd == -1 || pthread_create(&pmthr_tid, &thr_attr,
            pmthr, (void *)NULL) != 0) {
            envd_close_pm();
            envd_log(LOG_CRIT, PM_THREAD_CREATE_FAILED);
        } else
            pmthr_created = B_TRUE;
    }
    return (0);
}


static void
piclenvd_register(void)
{
    picld_plugin_register(&my_reg_info);
}

static void
piclenvd_init(void)
{
    /*
     * Start environmental daemon/threads
     */
    if (envd_setup() != 0) {
        envd_log(LOG_CRIT, ENVD_PLUGIN_INIT_FAILED);
        return;
    }

    /*
     * Now setup/populate PICL tree
     */
    env_picl_setup();
}

static void
piclenvd_fini(void)
{
    void    *exitval;

    /*
     * Kill both "envthr" and "pmthr" threads.
     */
    if (envthr_created) {
        (void) pthread_cancel(envthr_tid);
        (void) pthread_join(envthr_tid, &exitval);
        envthr_created = B_FALSE;
    }

    if (pmthr_created) {
        (void) pthread_cancel(pmthr_tid);
        (void) pthread_join(pmthr_tid, &exitval);
        pmthr_created = B_FALSE;
    }

    /*
     * close all sensors, fans and the power management device
     */
    envd_close_pm();
    envd_close_fans();
    envd_close_sensors();
    envd_inited = B_FALSE;
}

/*VARARGS2*/
void
envd_log(int pri, const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    vsyslog(pri, fmt, ap);
    va_end(ap);
}