8322 nl: misleading-indentation

[unleashed/tickless.git] / usr / src / cmd / picl / plugins / sun4u / 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);
}