dmake: do not set MAKEFLAGS=k

[unleashed/tickless.git] / usr / src / cmd / picl / plugins / sun4u / excalibur / 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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

/*
 * This file contains the environmental PICL plug-in module.
 */


/*
 * Excalibur system contains up to two CPU and two PCI MAX1617 temperature
 * devices, each consisting of two sensors: die and 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 monitor 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
 *
 * Above mentioned 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.
 *
 * Excalibur system contains three fans: cpu, system and power supply. The
 * cpu and system fans are under software control and their speed can be
 * set to a value in the range 0 through 63. However, the software has no
 * control over the power supply fan's speed (it's automatically controlled
 * by the hardware), but it can turn it ON or OFF. When in EStar mode (i.e.
 * the lowest power state), the environmental monitor turns off the power
 * supply fan.
 *
 * Each fan is represented as a different minor device and the fan speed
 * can be controlled by writing to the TDA8444 device driver. Note that
 * these devices are read only and the driver caches the last speed set
 * for each fan, thus allowing an interface to read the current fan speed
 * also.
 *
 * The policy to control fan speed depends upon the sensor. For CPU die
 * sensor, different policy is used depending upon whether the temperature
 * is rising, falling or steady state. In case of CPU ambient sensor, only
 * one policy (speed proportional to the current temperature) is used.
 *
 * 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.
 *
 * Once the "envthr" and "pmthr" threads have been started, they are never
 * killed. This is desirable so that we can do environmental monitoring
 * during reinit process.  The "envd_rwlock" reader/writer lock is used
 * to protect initialization of global state during reinit process against
 * the "envthr" and "pmthr" trying to reference that state.
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/sysmacros.h>
#include <limits.h>
#include <string.h>
#include <stdarg.h>
#include <alloca.h>
#include <unistd.h>
#include <sys/processor.h>
#include <syslog.h>
#include <errno.h>
#include <fcntl.h>
#include <picl.h>
#include <picltree.h>
#include <picldefs.h>
#include <pthread.h>
#include <signal.h>
#include <libdevinfo.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 <sys/xcalwd.h>
#include "envd.h"

static pthread_rwlock_t envd_rwlock = PTHREAD_RWLOCK_INITIALIZER;

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

#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,
};


/*
 * Default threshold values for CPU junction/die and ambient sensors
 */
static sensor_thresh_t cpu_die_thresh_default = {
        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,
        MAX1617_MIN_TEMP, MAX1617_MAX_TEMP,
        POLICY_TARGET_TEMP, 2,
        CPU_DIE_NORMAL_TARGET, CPU_DIE_OTHER_TARGET,
        0, 0, 0, 0
};

static sensor_thresh_t cpu_amb_thresh_default = {
        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,
        MAX1617_MIN_TEMP, MAX1617_MAX_TEMP,
        POLICY_LINEAR, 2,
        CPU_AMB_LOW_NOMINAL, CPU_AMB_HIGH_NOMINAL,
        0, 0, 0, 0
};


/*
 * Dummy sensor threshold data structure for processing threshold tuneables
 */
static sensor_thresh_t  dummy_thresh;

/*
 * Temperature related constants for fan speed adjustment
 */
#define AVG_TEMP_HYSTERESIS     0.25
#define RISING_TEMP_MARGIN      6
#define FALLING_TEMP_MARGIN     3

/*
 * tuneable variables
 */
#define FAN_SLOW_ADJUSTMENT     20              /* in percentage */
#define FAN_INCREMENT_LIMIT     6               /* absolute value */
#define FAN_DECREMENT_LIMIT     1               /* absolute value */
#define DEVFSADM_CMD            "/usr/sbin/devfsadm -i max1617"
#define FRU_DEVFSADM_CMD        "/usr/sbin/devfsadm -i seeprom"

int             env_debug;
static int      sensor_poll_interval;
static int      warning_interval;
static int      warning_duration;
static int      shutdown_interval;
static int      fan_slow_adjustment;
static int      fan_incr_limit;
static int      fan_decr_limit;
static int      disable_piclenvd;
static int      disable_warning;
static int      disable_power_off;
static int      disable_shutdown;

static char     shutdown_cmd[128];
static char     devfsadm_cmd[128];
static char     fru_devfsadm_cmd[128];
static sensor_thresh_t cpu0_die_thresh, cpu0_amb_thresh;
static sensor_thresh_t cpu1_die_thresh, cpu1_amb_thresh;

/*
 * Temperature sensors
 */

static env_sensor_t envd_sensors[] = {
        { SENSOR_CPU0_DIE, CPU0_DIE_SENSOR_DEVFS, &cpu0_die_thresh,
            CPU0_FRU_DEVFS, CPU_FRU_DIE_SENSOR,
            SFLAG_TARGET_TEMP | SFLAG_CPU_DIE_SENSOR, -1},
        { SENSOR_CPU0_AMB, CPU0_AMB_SENSOR_DEVFS, &cpu0_amb_thresh,
            CPU0_FRU_DEVFS, CPU_FRU_AMB_SENSOR, SFLAG_CPU_AMB_SENSOR, -1},
        { SENSOR_CPU1_DIE, CPU1_DIE_SENSOR_DEVFS, &cpu1_die_thresh,
            CPU1_FRU_DEVFS, CPU_FRU_DIE_SENSOR,
            SFLAG_TARGET_TEMP | SFLAG_CPU_DIE_SENSOR, -1},
        { SENSOR_CPU1_AMB, CPU1_AMB_SENSOR_DEVFS, &cpu1_amb_thresh,
            CPU1_FRU_DEVFS, CPU_FRU_AMB_SENSOR, SFLAG_CPU_AMB_SENSOR, -1},
        { NULL, NULL, NULL, NULL, 0, 0, -1}
};


/*
 * Fan devices
 */
static env_fan_t envd_system_fan = {
        ENV_SYSTEM_FAN, ENV_SYSTEM_FAN_DEVFS,
        SYSTEM_FAN_SPEED_MIN, SYSTEM_FAN_SPEED_MAX, -1, -1,
};

static env_fan_t envd_cpu_fan = {
        ENV_CPU_FAN, ENV_CPU_FAN_DEVFS,
        CPU_FAN_SPEED_MIN, CPU_FAN_SPEED_MAX, -1, -1,
};

static env_fan_t envd_psupply_fan = {
        ENV_PSUPPLY_FAN, ENV_PSUPPLY_FAN_DEVFS,
        PSUPPLY_FAN_SPEED_MIN, PSUPPLY_FAN_SPEED_MAX, -1, -1,
};

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

/*
 * Linked list of devices advertising lpm-ranges
 */
static lpm_dev_t        *lpm_devices = NULL;

/*
 * Excalibur lpm to system-fan speed
 * lpm values must be monotonically increasing (avoid divide-by-zero)
 */
static point_t  excal_lpm_system_fan_tbl[] = {
        /* {lpm, fspeed} */
        {18, 12},
        {25, 20},
        {33, 26},
        {44, 32},
        {51, 39},
        {63, 52},
        {64, 63}
};

static table_t  lpm_fspeed = {
        sizeof (excal_lpm_system_fan_tbl)/ sizeof (point_t),
        excal_lpm_system_fan_tbl
};

/*
 * Sensor to fan map
 */
typedef struct {
        char    *sensor_name;
        char    *fan_name;
} sensor_fan_map_t;

static sensor_fan_map_t sensor_fan_map[] = {
        {SENSOR_CPU0_DIE, ENV_CPU_FAN},
        {SENSOR_CPU1_DIE, ENV_CPU_FAN},
        {SENSOR_CPU0_AMB, ENV_SYSTEM_FAN},
        {SENSOR_CPU1_AMB, ENV_SYSTEM_FAN},
        {NULL, NULL}
};

/*
 * Sensor to PM device map
 */
struct sensor_pmdev {
        int             sensor_id;
        char            *sensor_name;
        char            *pmdev_name;
        char            *speed_comp_name;
        int             speed_comp;
        int             full_power;
        int             cur_power;
        env_sensor_t    *sensorp;
        sensor_pmdev_t  *next;
};

#define SPEED_COMPONENT_NAME    "CPU Speed"

static sensor_pmdev_t sensor_pmdevs[] = {
        {SENSOR_CPU0_ID, SENSOR_CPU0_DIE, NULL, SPEED_COMPONENT_NAME},
        {SENSOR_CPU1_ID, SENSOR_CPU1_DIE, NULL, SPEED_COMPONENT_NAME},
        {-1, NULL, NULL, NULL}
};

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

/*
 * Power management thread (pmthr) variables
 */
static boolean_t        pmdev_names_init = B_FALSE;
static pthread_t        pmthr_tid;              /* pmthr thread ID */
static int              pmthr_exists = B_FALSE; /* pmthr exists */
static int              pm_fd = -1;             /* PM device file descriptor */
static int              cur_lpstate;            /* cur low power state */

/*
 * Miscellaneous variables and declarations
 */
static int      fru_devfsadm_invoked = 0;
static int      devfsadm_invoked = 0;
static char     tokdel[] = " \t\n\r";
static uint_t   envd_sleep(uint_t);

/*
 * Tuneable data structure/array and processing functions
 */

typedef struct {
        char            *name;          /* keyword */
        int             (*func)(char *, char *, void *, int, char *, int);
                                        /* tuneable processing function */
        void            *arg1;          /* tuneable arg1 (memory address) */
        int             arg2;           /* tuneable arg2 (size or flags) */
} env_tuneable_t;

static int process_int_tuneable(char *keyword, char *buf, void *addr,
    int size, char *fname, int line);
static int process_string_tuneable(char *keyword, char *buf, void *addr,
    int size, char *fname, int line);
static int process_threshold_tuneable(char *keyword, char *buf, void *addr,
    int flags, char *fname, int line);
static void process_env_conf_file(void);

static env_tuneable_t env_tuneables[] = {
        {"low_power_off", process_threshold_tuneable,
            &dummy_thresh.low_power_off, 0},
        {"low_shutdown", process_threshold_tuneable,
            &dummy_thresh.low_shutdown, 0},
        {"low_warning", process_threshold_tuneable,
            &dummy_thresh.low_warning, 0},
        {"high_power_off", process_threshold_tuneable,
            &dummy_thresh.high_power_off, 0},
        {"high_shutdown", process_threshold_tuneable,
            &dummy_thresh.high_shutdown, 0},
        {"high_warning", process_threshold_tuneable,
            &dummy_thresh.high_warning, 0},
        {"force_cpu_fan", process_int_tuneable, &envd_cpu_fan.forced_speed,
            sizeof (envd_cpu_fan.forced_speed)},
        {"force_system_fan", process_int_tuneable,
            &envd_system_fan.forced_speed,
            sizeof (envd_system_fan.forced_speed)},

        {"cpu_amb_low_power_off", process_threshold_tuneable,
            &dummy_thresh.low_power_off, SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_low_shutdown", process_threshold_tuneable,
            &dummy_thresh.low_shutdown, SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_low_warning", process_threshold_tuneable,
            &dummy_thresh.low_warning, SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_low_nominal", process_threshold_tuneable,
            &dummy_thresh.policy_data[LOW_NOMINAL_LOC], SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_high_power_off", process_threshold_tuneable,
            &dummy_thresh.high_power_off, SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_high_shutdown", process_threshold_tuneable,
            &dummy_thresh.high_shutdown, SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_high_warning", process_threshold_tuneable,
            &dummy_thresh.high_warning, SFLAG_CPU_AMB_SENSOR},
        {"cpu_amb_high_nominal", process_threshold_tuneable,
            &dummy_thresh.policy_data[HIGH_NOMINAL_LOC], SFLAG_CPU_AMB_SENSOR},

        {"cpu_die_low_power_off", process_threshold_tuneable,
            &dummy_thresh.low_power_off, SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_low_shutdown", process_threshold_tuneable,
            &dummy_thresh.low_shutdown, SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_low_warning", process_threshold_tuneable,
            &dummy_thresh.low_warning, SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_normal_target", process_threshold_tuneable,
            &dummy_thresh.policy_data[0], SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_high_power_off", process_threshold_tuneable,
            &dummy_thresh.high_power_off, SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_high_shutdown", process_threshold_tuneable,
            &dummy_thresh.high_shutdown, SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_high_warning", process_threshold_tuneable,
            &dummy_thresh.high_warning, SFLAG_CPU_DIE_SENSOR},
        {"cpu_die_other_target", process_threshold_tuneable,
            &dummy_thresh.policy_data[1], SFLAG_CPU_DIE_SENSOR},

        {"sensor_poll_interval", process_int_tuneable, &sensor_poll_interval,
            sizeof (sensor_poll_interval)},
        {"warning_interval", process_int_tuneable, &warning_interval,
            sizeof (warning_interval)},
        {"warning_duration", process_int_tuneable, &warning_duration,
            sizeof (warning_duration)},
        {"disable_piclenvd", process_int_tuneable, &disable_piclenvd,
            sizeof (disable_piclenvd)},
        {"disable_power_off", process_int_tuneable, &disable_power_off,
            sizeof (disable_power_off)},
        {"disable_warning", process_int_tuneable, &disable_warning,
            sizeof (disable_warning)},
        {"disable_shutdown", process_int_tuneable, &disable_shutdown,
            sizeof (disable_shutdown)},
        {"shutdown_interval", process_int_tuneable, &shutdown_interval,
            sizeof (shutdown_interval)},
        {"shutdown_cmd", process_string_tuneable, &shutdown_cmd[0],
            sizeof (shutdown_cmd)},
        {"devfsadm_cmd", process_string_tuneable, &devfsadm_cmd[0],
            sizeof (devfsadm_cmd)},
        {"fru_devfsadm_cmd", process_string_tuneable, &fru_devfsadm_cmd[0],
            sizeof (fru_devfsadm_cmd)},
        {"fan_slow_adjustment", process_int_tuneable, &fan_slow_adjustment,
            sizeof (fan_slow_adjustment)},
        {"fan_incr_limit", process_int_tuneable, &fan_incr_limit,
            sizeof (fan_incr_limit)},
        {"fan_decr_limit", process_int_tuneable, &fan_decr_limit,
            sizeof (fan_decr_limit)},
        {"env_debug", process_int_tuneable, &env_debug, sizeof (env_debug)},
        { NULL, NULL, NULL, 0}
};

static void
fini_table(table_t *tblp)
{
        if (tblp == NULL)
                return;
        free(tblp->xymap);
        free(tblp);
}

static table_t *
init_table(int npoints)
{
        table_t         *tblp;
        point_t         *xy;

        if (npoints == 0)
                return (NULL);

        if ((tblp = malloc(sizeof (*tblp))) == NULL)
                return (NULL);

        if ((xy = malloc(sizeof (*xy) * npoints)) == NULL) {
                free(tblp);
                return (NULL);
        }

        tblp->nentries = npoints;
        tblp->xymap = xy;

        return (tblp);
}

/*
 * Temp-LPM Table format:
 * temp, lpm, temp, lpm, ...
 */
static table_t *
parse_lpm_ranges(uint32_t *bufp, size_t nbytes)
{
        int     nentries;
        table_t *tblp = NULL;
        int     i;

        if (bufp == NULL)
                return (NULL);

        /*
         * Table should have at least 2 points
         * and all points should have x and y values
         */
        if ((nbytes < (2 * sizeof (point_t))) ||
            (nbytes & (sizeof (point_t) - 1))) {
                if (env_debug)
                        envd_log(LOG_ERR, ENV_INVALID_PROPERTY_FORMAT,
                            LPM_RANGES_PROPERTY);
                return (NULL);
        }

        /* number of entries in the temp-lpm table */
        nentries = nbytes/sizeof (point_t);

        tblp = init_table(nentries);
        if (tblp == NULL)
                return (tblp);

        /* copy the tuples */
        tblp->xymap[0].x = (int)*bufp++;
        tblp->xymap[0].y = (int)*bufp++;
        for (i = 1; i < nentries; ++i) {
                tblp->xymap[i].x = (int)*bufp++;
                tblp->xymap[i].y = (int)*bufp++;
                if (tblp->xymap[i].x <= tblp->xymap[i - 1].x) {
                        fini_table(tblp);
                        if (env_debug)
                                envd_log(LOG_ERR, ENV_INVALID_PROPERTY_FORMAT,
                                    LPM_RANGES_PROPERTY);
                        return (NULL);
                }
        }

        return (tblp);
}

/*
 * function: calculates y for a given x based on a table of points
 * for monotonically increasing x values.
 * 'tbl' specifies the table to use, 'val' specifies the 'x', returns 'y'
 */
static int
y_of_x(table_t *tbl, int xval)
{
        int             i;
        int             entries;
        point_t         *xymap;
        float           newval;
        float           dy, dx, slope;

        entries = tbl->nentries;
        xymap = tbl->xymap;
        if (xval <= xymap[0].x)
                return (xymap[0].y);
        else if (xval >= xymap[entries - 1].x)
                return (xymap[entries - 1].y);

        for (i = 1; i < entries - 1; i++) {
                if (xval == xymap[i].x)
                        return (xymap[i].y);
                if (xval < xymap[i].x)
                        break;
        }

        /*
         * Use linear interpolation
         */
        dy = (float)(xymap[i].y - xymap[i-1].y);
        dx = (float)(xymap[i].x - xymap[i-1].x);
        slope = dy/dx;
        newval = xymap[i - 1].y + slope * (xval - xymap[i - 1].x);
        return ((int)(newval + (newval >= 0 ? 0.5 : -0.5)));
}

static int
get_lpm_speed(lpm_dev_t *lpmdevs, int temp)
{
        lpm_dev_t       *devp;
        int             lpm;
        int             speed;
        int             maxspeed;

        if (lpmdevs == NULL)
                return (0);
        maxspeed = 0;
        for (devp = lpmdevs; devp != NULL; devp = devp->next) {
                if (devp->temp_lpm_tbl == NULL)
                        continue;
                lpm = y_of_x(devp->temp_lpm_tbl, temp);
                if (env_debug)
                        envd_log(LOG_INFO, "ambient %d lpm %d\n", temp, lpm);
                speed = y_of_x(&lpm_fspeed, lpm);
                maxspeed = maxspeed > speed ? maxspeed : speed;
                if (env_debug)
                        envd_log(LOG_INFO, "lpm %d fanspeed %d\n", lpm, speed);
        }
        return (maxspeed);
}

/*
 * Callback function used by ptree_walk_tree_by_class
 */
static int
cb_lpm(picl_nodehdl_t nodeh, void *args)
{
        lpm_dev_t       **retp = (lpm_dev_t **)args;
        int             err;
        ptree_propinfo_t        pinfo;
        picl_prophdl_t          proph;
        size_t                  psize;
        void                    *bufp;
        table_t                 *temp_lpm_tbl;
        lpm_dev_t               *newdev;

        err = ptree_get_prop_by_name(nodeh, LPM_RANGES_PROPERTY, &proph);
        if (err != PICL_SUCCESS)
                return (PICL_WALK_CONTINUE);

        err = ptree_get_propinfo(proph, &pinfo);
        if ((err != PICL_SUCCESS) ||
            (pinfo.piclinfo.type != PICL_PTYPE_BYTEARRAY))
                return (PICL_WALK_CONTINUE);
        psize = pinfo.piclinfo.size;
        bufp = alloca(psize);

        err = ptree_get_propval(proph, bufp, psize);
        if (err != PICL_SUCCESS)
                return (PICL_WALK_CONTINUE);

        temp_lpm_tbl = parse_lpm_ranges(bufp, psize);
        if (temp_lpm_tbl == NULL) {
                return (PICL_WALK_CONTINUE);
        }

        newdev = malloc(sizeof (*newdev));
        if (newdev == NULL) {
                fini_table(temp_lpm_tbl);
                return (PICL_WALK_TERMINATE);
        }

        memset(newdev, 0, sizeof (*newdev));

        newdev->nodeh = nodeh;
        newdev->temp_lpm_tbl = temp_lpm_tbl;

        /* add newdev to the list */
        newdev->next = *retp;
        *retp = newdev;

        return (PICL_WALK_CONTINUE);
}

/*
 * Find all devices advertising "lpm-ranges" property, parse and store
 * the lpm tables for each device
 */
static int
setup_lpm_devices(lpm_dev_t **devpp)
{
        picl_nodehdl_t  plath;
        int             err;
        lpm_dev_t       *lpmp;

        err = ptree_get_node_by_path("/platform", &plath);
        if (err != PICL_SUCCESS)
                return (err);

        lpmp = NULL;
        err = ptree_walk_tree_by_class(plath, NULL, (void *)&lpmp, cb_lpm);
        if (err == PICL_SUCCESS)
                *devpp = lpmp;
        return (err);
}

/*
 * Remove all lpm_devices and their tables.
 */
static void
delete_lpm_devices(void)
{
        lpm_dev_t       *devp, *next;

        (void) pthread_rwlock_wrlock(&envd_rwlock);

        if (lpm_devices == NULL) {
                (void) pthread_rwlock_unlock(&envd_rwlock);
                return;
        }

        devp = lpm_devices;

        while (devp != NULL) {
                fini_table(devp->temp_lpm_tbl);
                next = devp->next;
                free(devp);
                devp = next;
        }

        lpm_devices = NULL;

        (void) pthread_rwlock_unlock(&envd_rwlock);
}

/*
 * Translate observed (measured) temperature into expected (correct)
 * temperature
 */
static int
xlate_obs2exp(env_sensor_t *sensorp, tempr_t temp)
{
        int             i, entries, new_temp, denominator;
        tempr_map_t     *map;
        float           ftemp;

        entries = sensorp->obs2exp_cnt;
        map = sensorp->obs2exp_map;
        if (entries < 2 || map == NULL)  {
                /* no map or can't map it */
                new_temp = temp;
        } else {
                /*
                 * Any point beyond the range specified by the map is
                 * extrapolated using either the first two or the last
                 * two entries in the map.
                 */
                for (i = 1; i < entries-1; i++)
                        if (temp < map[i].observed)
                                break;
                /*
                 * Interpolate/extrapolate the temperature using linear
                 * equation with map[i-1] and map[i] being the two ends
                 * of the line segment.
                 */
                denominator = map[i].observed - map[i-1].observed;
                if (denominator == 0) {
                        /*
                         * Infinite slope. Since the temperature reading
                         * resolution is 1C, force denominator to 1 to
                         * avoid divide by zero.
                         */
                        denominator = 1;
                }
                ftemp = map[i-1].expected +  (temp - map[i-1].observed) *
                    (float)(map[i].expected - map[i-1].expected)/denominator;
                new_temp = (int)(ftemp + (ftemp >= 0 ? 0.5 : -0.5));
        }

        return (new_temp);
}


/*
 * Translate expected (correct) temperature into observed (measured)
 * temperature
 */
static int
xlate_exp2obs(env_sensor_t *sensorp, tempr_t temp)
{
        int             i, entries, new_temp, denominator;
        tempr_map_t     *map;
        float           ftemp;
        sensor_thresh_t *threshp = sensorp->temp_thresh;

        entries = sensorp->obs2exp_cnt;
        map = sensorp->obs2exp_map;
        if (entries < 2 || map == NULL)
                /* no map or can't map it */
                new_temp = temp;
        else {
                /*
                 * Any point beyond the range specified by the map is
                 * extrapolated using either the first two or the last
                 * two entries in the map.
                 */
                for (i = 1; i < entries-1; i++)
                        if (temp < map[i].expected)
                                break;

                /*
                 * Interpolate/extrapolate the temperature using linear
                 * equation with map[i-1] and map[i] being the two ends
                 * of the line segment.
                 */
                denominator = map[i].expected - map[i-1].expected;
                if (denominator == 0) {
                        /*
                         * Infinite slope. Since the temperature reading
                         * resolution is 1C, force denominator to 1 to
                         * avoid divide by zero.
                         */
                        denominator = 1;
                }
                ftemp = map[i-1].observed + (temp - map[i-1].expected) *
                    (float)(map[i].observed - map[i-1].observed)/denominator;
                new_temp = (int)(ftemp + (ftemp >= 0 ? 0.5 : -0.5));
        }

        if (threshp) {
                if (new_temp > threshp->max_limit)
                        new_temp = threshp->max_limit;
                else if (new_temp < threshp->min_limit)
                        new_temp = threshp->min_limit;
        }

        return (new_temp);
}


/*
 * Check if the specified FRU is present.
 * Returns 1 if present; 0 otherwise.
 */
static int
fru_present(char *path)
{
        char            *p, physpath[PATH_MAX];
        di_node_t       root_node;
        int             fru_present = 0;

        /*
         * Construct FRU device path by stripping minor
         * node name from the path and use di_init() to
         * see if the node exists.
         */
        (void) strlcpy(physpath, path, sizeof (physpath));
        p = strrchr(physpath, ':');
        if (p != NULL)
                *p = '\0';
        if ((root_node = di_init(physpath, DINFOMINOR)) != DI_NODE_NIL) {
                di_fini(root_node);
                fru_present = 1;
        }
        return (fru_present);
}


/*
 * Get environmental segment from the specified FRU SEEPROM
 */
static int
get_envseg(int fd, void **envsegp, int *envseglenp)
{
        int                     i, segcnt, envseglen;
        section_layout_t        section;
        segment_layout_t        segment;
        uint8_t                 *envseg;

        if (lseek(fd, (long)SECTION_HDR_OFFSET, 0) == -1L ||
            read(fd, &section, sizeof (section)) != sizeof (section)) {
                return (EINVAL);
        }

        /*
         * Verify we have the correct section and contents are valid
         * For now, we don't verify the CRC.
         */
        if (section.header_tag != SECTION_HDR_TAG ||
            GET_UNALIGN16(&section.header_version[0]) != SECTION_HDR_VER) {
                if (env_debug)
                        envd_log(LOG_INFO,
                            "Invalid section header tag:%x  version:%x\n",
                            section.header_tag,
                            GET_UNALIGN16(&section.header_version));
                return (EINVAL);
        }

        /*
         * Locate our environmental segment
         */
        segcnt = section.segment_count;
        for (i = 0; i < segcnt; i++) {
                if (read(fd, &segment, sizeof (segment)) != sizeof (segment)) {
                        return (errno);
                }
                if (env_debug > 1)
                        envd_log(LOG_INFO,
                            "Seg name: %x  desc:%x off:%x  len:%x\n",
                            GET_UNALIGN16(&segment.name),
                            GET_UNALIGN32(&segment.descriptor[0]),
                            GET_UNALIGN16(&segment.offset),
                            GET_UNALIGN16(&segment.length));

                if (GET_UNALIGN16(&segment.name) == ENVSEG_NAME)
                        break;
        }

        if (i >= segcnt) {
                return (ENOENT);
        }

        /*
         * Allocate memory to hold the environmental segment data.
         */
        envseglen = GET_UNALIGN16(&segment.length);
        if ((envseg = malloc(envseglen)) == NULL) {
                return (ENOMEM);
        }

        if (lseek(fd, (long)GET_UNALIGN16(&segment.offset), 0) == -1L ||
            read(fd, envseg, envseglen) != envseglen) {
                (void) free(envseg);
                return (EIO);
        }

        *envsegp = envseg;
        *envseglenp = envseglen;

        if (env_debug > 1) {
                char    msgbuf[256];
                for (i = 0; i < envseglen; i++) {
                        (void) sprintf(&msgbuf[3*(i&0xf)], "%2x ", envseg[i]);
                        if ((i & 0xf) == 0xf || i == (envseglen-1))
                                envd_log(LOG_INFO, "envseg[%2x]: %s\n",
                                    (i & ~0xf), msgbuf);
                }
        }

        return (0);
}


/*
 * Get all environmental segments
 */
static fruenvseg_t *
get_fru_envsegs(void)
{
        env_sensor_t            *sensorp;
        fruenvseg_t             *frup, *fruenvsegs;
        envseg_layout_t         *envsegp;
        void                    *envsegbufp;
        int                     fd, envseglen, hdrlen;
        char                    path[PATH_MAX];

        fruenvsegs = NULL;
        for (sensorp = &envd_sensors[0]; sensorp->name != NULL; sensorp++) {
                if (sensorp->fru == NULL)
                        continue;

                for (frup = fruenvsegs; frup != NULL; frup = frup->next)
                        if (strcmp(frup->fru, sensorp->fru) == 0)
                                break;

                if (frup != NULL)
                        continue;

                frup = (fruenvseg_t *)malloc(sizeof (fruenvseg_t));
                if (frup == NULL)
                        continue;

                /* add this FRU to our list */
                frup->fru = sensorp->fru;
                frup->envsegbufp = NULL;
                frup->envseglen = 0;
                frup->next = fruenvsegs;
                fruenvsegs = frup;

                /*
                 * Now get the environmental segment from this FRU
                 */
                (void) strcpy(path, "/devices");
                (void) strlcat(path, sensorp->fru, sizeof (path));
        retry:
                errno = 0;
                fd = open(path, O_RDONLY);
                if (env_debug > 1)
                        envd_log(LOG_INFO,
                            "fru SEEPROM: %s fd: %d  errno:%d\n",
                            path, fd, errno);
                if (fd == -1 && errno == ENOENT && fru_present(frup->fru)) {
                        if (fru_devfsadm_invoked ||
                            fru_devfsadm_cmd[0] == '\0') {
                                envd_log(LOG_CRIT, ENV_FRU_OPEN_FAIL,
                                    sensorp->fru, errno, strerror(errno));
                                continue;

                        }
                        /*
                         * FRU is present but no path exists as
                         * someone rebooted the system without
                         * "-r" option. Let's invoke "devfsadm"
                         * once to create seeprom nodes and try
                         * again so that we can monitor all
                         * accessible sensors properly and prevent
                         * any CPU overheating.
                         */
                        if (env_debug)
                                envd_log(LOG_INFO,
                                    "Invoking '%s' to create FRU nodes\n",
                                    fru_devfsadm_cmd);
                        fru_devfsadm_invoked = 1;
                        (void) system(fru_devfsadm_cmd);
                        goto retry;
                }

                /*
                 * Read environmental segment from this FRU SEEPROM
                 */
                if (get_envseg(fd, &envsegbufp, &envseglen) == 0) {
                        /*
                         * Validate envseg version number and header length
                         */
                        envsegp = (envseg_layout_t *)envsegbufp;
                        hdrlen = sizeof (envseg_layout_t) -
                            sizeof (envseg_sensor_t) +
                            (envsegp->sensor_count) * sizeof (envseg_sensor_t);

                        if (envsegp->version != ENVSEG_VERSION ||
                            envseglen < hdrlen) {
                                /*
                                 * version mismatch or header not big enough
                                 */
                                envd_log(LOG_CRIT, ENV_FRU_BAD_ENVSEG,
                                    sensorp->fru, errno, strerror(errno));
                                if (envsegbufp != NULL)
                                        (void) free(envsegbufp);
                        } else {
                                frup->envseglen = envseglen;
                                frup->envsegbufp = envsegbufp;
                        }
                }
                (void) close(fd);
        }
        return (fruenvsegs);
}

/*
 * Process environmental segment for all FRUs.
 */
static void
process_fru_envseg()
{
        env_sensor_t            *sensorp;
        sensor_thresh_t         *threshp;
        envseg_layout_t         *envsegp;
        envseg_sensor_data_t    *datap;
        fruenvseg_t             *frup, *fruenvsegs;
        int                     i, envseglen, sensorcnt;
        uint_t                  offset, length, mapentries;

        /*
         * Lookup/read environmental segments from FRU SEEPROMs and
         * process it. Note that we read each SEEPROM once as it's
         * a slow device.
         */
        fruenvsegs = get_fru_envsegs();

        for (sensorp = &envd_sensors[0]; sensorp->name != NULL; sensorp++) {
                if (sensorp->fru == NULL)
                        continue;

                /*
                 * Locate our FRU environmental segment
                 */
                for (frup = fruenvsegs; frup != NULL; frup = frup->next)
                        if (strcmp(frup->fru, sensorp->fru) == 0)
                                break;
                if (frup == NULL || frup->envsegbufp == NULL)
                        continue;

                envsegp = (envseg_layout_t *)frup->envsegbufp;
                envseglen = frup->envseglen;
                sensorcnt = envsegp->sensor_count;

                /*
                 * Locate our sensor data record entry
                 */
                for (i = 0; i < sensorcnt; i++) {
                        uint32_t        id;

                        id = GET_UNALIGN32(&envsegp->sensors[i].sensor_id[0]);
                        if (env_debug > 1)
                                envd_log(LOG_INFO, " sensor[%d]: id:%x\n",
                                    i, id);
                        if (id == sensorp->fru_sensor)
                                break;
                }

                if (i >= sensorcnt)
                        continue;

                /*
                 * Validate offset/length of our sensor data record
                 */
                offset = (uint_t)GET_UNALIGN16(&envsegp->sensors[i].offset);
                datap =  (envseg_sensor_data_t *)((intptr_t)frup->envsegbufp +
                    offset);
                mapentries =  GET_UNALIGN16(&datap->obs2exp_cnt);
                length = sizeof (envseg_sensor_data_t) - sizeof (envseg_map_t) +
                    mapentries * sizeof (envseg_map_t);

                if (env_debug > 1)
                        envd_log(LOG_INFO, "Found sensor_id:%x idx:%x "
                        "off:%x #maps:%x expected length:%x\n",
                                sensorp->fru_sensor, i, offset,
                                mapentries, length);

                if (offset >= envseglen || (offset+length) > envseglen) {
                        /* corrupted sensor record */
                        envd_log(LOG_CRIT, ENV_FRU_BAD_SENSOR_ENTRY,
                            sensorp->fru_sensor, sensorp->name, sensorp->fru);
                        continue;
                }

                if (env_debug > 1) {
                        /* print threshold values */
                        envd_log(LOG_INFO,
                            "Thresholds: HPwrOff %d  HShutDn %d  HWarn %d\n",
                            datap->high_power_off, datap->high_shutdown,
                            datap->high_warning);
                        envd_log(LOG_INFO,
                            "Thresholds: LWarn %d  LShutDn %d  LPwrOff %d\n",
                            datap->low_warning, datap->low_shutdown,
                            datap->low_power_off);

                        /* print policy data */
                        envd_log(LOG_INFO,
                            " Policy type: %d #%d data: %x %x %x %x %x %x\n",
                            datap->policy_type, datap->policy_entries,
                            datap->policy_data[0], datap->policy_data[1],
                            datap->policy_data[2], datap->policy_data[3],
                            datap->policy_data[4], datap->policy_data[5]);

                        /* print map table */
                        for (i = 0; i < mapentries; i++) {
                                envd_log(LOG_INFO, " Map pair# %d: %d %d\n",
                                    i, datap->obs2exp_map[i].observed,
                                    datap->obs2exp_map[i].expected);
                        }
                }


                /*
                 * Copy threshold values
                 */
                threshp = sensorp->temp_thresh;
                threshp->high_power_off = datap->high_power_off;
                threshp->high_shutdown = datap->high_shutdown;
                threshp->high_warning = datap->high_warning;
                threshp->low_warning = datap->low_warning;
                threshp->low_shutdown = datap->low_shutdown;
                threshp->low_power_off = datap->low_power_off;

                /*
                 * Copy policy data
                 */
                threshp->policy_type = datap->policy_type;
                threshp->policy_entries = datap->policy_entries;
                for (i = 0; i < MAX_POLICY_ENTRIES; i++)
                        threshp->policy_data[i] =
                            (tempr_t)datap->policy_data[i];

                /*
                 * Copy temperature mapping info (discard duplicate entries)
                 */
                if (sensorp->obs2exp_map) {
                        (void) free(sensorp->obs2exp_map);
                        sensorp->obs2exp_map = NULL;
                        sensorp->obs2exp_cnt = 0;
                }
                if (mapentries > 0) {
                        tempr_map_t     *map;
                        int             cnt;
                        tempr_t         observed, expected;

                        map = (tempr_map_t *)malloc(mapentries *
                            sizeof (tempr_map_t));

                        if (map == NULL) {
                                envd_log(LOG_CRIT, ENV_FRU_SENSOR_MAP_NOMEM,
                                    sensorp->fru_sensor, sensorp->name,
                                    sensorp->fru);
                                continue;
                        }

                        for (i = 0, cnt = 0; i < mapentries; i++) {

                                observed = (tempr_t)
                                    datap->obs2exp_map[i].observed;
                                expected = (tempr_t)
                                    datap->obs2exp_map[i].expected;

                                /* ignore if duplicate entry */
                                if (cnt > 0 &&
                                    observed == map[cnt-1].observed &&
                                    expected == map[cnt-1].expected) {
                                        continue;
                                }
                                map[cnt].observed = observed;
                                map[cnt].expected = expected;
                                cnt++;
                        }
                        sensorp->obs2exp_cnt = cnt;
                        sensorp->obs2exp_map = map;
                }

                if (env_debug > 2 && sensorp->obs2exp_cnt > 1) {
                        char    msgbuf[256];

                        envd_log(LOG_INFO,
                            "Measured --> Correct temperature table "
                            "for sensor: %s\n", sensorp->name);
                        for (i = -128; i < 128; i++) {
                                (void) sprintf(&msgbuf[6*(i&0x7)], "%6d",
                                    xlate_obs2exp(sensorp, i));
                                if ((i &0x7) == 0x7)
                                        envd_log(LOG_INFO,
                                            "%8d: %s\n", (i & ~0x7), msgbuf);
                        }
                        if ((i & 0x7) != 0)
                                (void) printf("%8d: %s\n", (i & ~0x7), msgbuf);

                        envd_log(LOG_INFO,
                            "Correct --> Measured temperature table "
                            "for sensor: %s\n", sensorp->name);
                        for (i = -128; i < 128; i++) {
                                (void) sprintf(&msgbuf[6*(i&0x7)], "%6d",
                                    xlate_exp2obs(sensorp, i));
                                if ((i &0x7) == 0x7)
                                        envd_log(LOG_INFO,
                                            "%8d: %s\n", (i & ~0x7), msgbuf);
                        }
                        if ((i & 0x7) != 0)
                                envd_log(LOG_INFO,
                                    "%8d: %s\n", (i & ~0x7), msgbuf);
                }
        }

        /*
         * Deallocate environmental segment list
         */
        while (fruenvsegs) {
                frup = fruenvsegs;
                fruenvsegs = frup->next;
                if (frup->envsegbufp != NULL)
                        (void) free(frup->envsegbufp);
                (void) free(frup);
        }
}

/*
 * 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)
{
        env_sensor_t    *sensorp;

        for (sensorp = &envd_sensors[0]; sensorp->name != NULL; sensorp++) {
                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;
        int     expected_temp;

        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);
        } else if (sensorp->obs2exp_map != NULL) {
                expected_temp = xlate_obs2exp(sensorp, (tempr_t)*temp);
                if (env_debug > 1)
                        envd_log(LOG_INFO,
                            "sensor: %-13s temp:%d  CORRECED to %d\n",
                            sensorp->name, *temp, (tempr_t)expected_temp);
                *temp = (tempr_t)expected_temp;
        }

        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)
{
        env_sensor_t    *sensorp;

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

/*
 * Open PM device
 */
static void
envd_open_pm(void)
{
        pm_fd = open(PM_DEVICE, O_RDONLY);
        if (pm_fd != -1)
                (void) fcntl(pm_fd, F_SETFD, FD_CLOEXEC);
}

/*
 * 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[PATH_MAX];
        int             fancnt = 0;
        char            *fan_name;
        sensor_fan_map_t *sfmap;
        env_sensor_t    *sensorp;
        int             sensor_cnt;

        for (i = 0; (fanp = envd_fans[i]) != NULL; i++) {
                if (fanp->fd == -1) {
                        fanp->sensor_cnt = 0;
                        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_CRIT,
                                    ENV_FAN_OPEN_FAIL, fanp->name,
                                    fanp->devfs_path, errno, strerror(errno));
                                fanp->present = B_FALSE;
                                continue;
                        }
                        (void) fcntl(fd, F_SETFD, FD_CLOEXEC);
                        fanp->fd = fd;
                        fanp->present = B_TRUE;
                }
                fancnt++;

                /*
                 * Set initial speed and update cur_speed/prev_speed
                 */
                if (fanp->forced_speed >= 0) {
                        speed = (fanspeed_t)fanp->forced_speed;
                        if (speed > fanp->speed_max)
                                speed = fanp->speed_max;
                        if (!disable_piclenvd)
                                (void) set_fan_speed(fanp, speed);
                } else if (get_fan_speed(fanp, &speed) == -1) {
                        /*
                         * The Fan driver does not know the current fan speed.
                         * Initialize all ON/OFF fans to ON state and all
                         * variable speed fans under software control to 50%
                         * of the max speed and reread the fan to get the
                         * current speed.
                         */
                        speed = (fanp == &envd_psupply_fan) ?
                                fanp->speed_max : fanp->speed_max/2;
                        if (!disable_piclenvd) {
                                (void) set_fan_speed(fanp, speed);
                                if (get_fan_speed(fanp, &speed) == -1)
                                        continue;
                        }
                }
                fanp->cur_speed = speed;
                fanp->prev_speed = speed;

                /*
                 * Process sensor_fan_map[] table and initialize sensors[]
                 * array for this fan.
                 */
                fan_name = fanp->name;
                for (sensor_cnt = 0, sfmap = &sensor_fan_map[0];
                    sfmap->sensor_name != NULL; sfmap++) {
                        if (strcmp(sfmap->fan_name, fan_name) != 0)
                                continue;
                        sensorp = sensor_lookup(sfmap->sensor_name);
                        if (sensorp != NULL && sensor_cnt < SENSORS_PER_FAN) {
                                fanp->sensors[sensor_cnt] = sensorp;
                                sensor_cnt++;
                        }
                }
                fanp->sensor_cnt = sensor_cnt;
        }

        return (fancnt);
}


/*
 * Adjust specified sensor target temperature and fan adjustment rate
 */

static void
adjust_sensor_target(env_sensor_t *sensorp)
{
        int             target, index;
        sensor_pmdev_t  *pmdevp;
        sensor_thresh_t *threshp;
        float           rate;

        /*
         * Look at current power state of all power managed devices
         * associated with this sensor and look up the desired target
         * temperature and pick the lowest one of those values. Also,
         * calculate the rate of change based upon whether one or more
         * of the associated power managed devices are not running at
         * full power mode.
         */

        if (sensorp == NULL || (threshp = sensorp->temp_thresh) == NULL ||
            threshp->policy_type != POLICY_TARGET_TEMP)
                return;

        target = threshp->policy_data[0];
        rate = 1.0;
        for (pmdevp = sensorp->pmdevp; pmdevp != NULL; pmdevp = pmdevp->next) {
                index = pmdevp->full_power - pmdevp->cur_power;
                if (index <= 0)
                        continue;

                /* not running at full power */
                if (index >= threshp->policy_entries)
                        index = threshp->policy_entries - 1;
                if (target > threshp->policy_data[index])
                        target = threshp->policy_data[index];
                if (rate > (float)fan_slow_adjustment/100)
                        rate = (float)fan_slow_adjustment/100;
                if (env_debug > 1)
                        envd_log(LOG_INFO,
                            "pmdev: %-13s new_target:%d  cur:%d power:%d/%d\n",
                            pmdevp->pmdev_name, target, sensorp->target_temp,
                            pmdevp->cur_power, pmdevp->full_power);
        }

        if (env_debug)
                envd_log(LOG_INFO,
                    "sensor: %-13s new_target:%d  cur:%d power:%d/%d\n",
                    sensorp->name, target, sensorp->target_temp,
                    ((sensorp->pmdevp) ? sensorp->pmdevp->cur_power : -1),
                    ((sensorp->pmdevp) ? sensorp->pmdevp->full_power : -1));

        sensorp->fan_adjustment_rate = rate;
        sensorp->target_temp = target;
}

/*
 * Update current power level of all PM devices we are tracking and adjust
 * the target temperature associated with the corresponding sensor.
 *
 * Returns 1 if one or more pmdev power level was adjusted; 0 otherwise.
 */
static int
update_pmdev_power()
{
        sensor_pmdev_t  *pmdevp;
        pm_req_t        pmreq;
        int             cur_power;
        int             updated = 0;

        for (pmdevp = sensor_pmdevs; pmdevp->pmdev_name != NULL; pmdevp++) {
                pmreq.physpath = pmdevp->pmdev_name;
                pmreq.data = NULL;
                pmreq.datasize = 0;
                pmreq.component = pmdevp->speed_comp;
                cur_power = ioctl(pm_fd, PM_GET_CURRENT_POWER, &pmreq);
                if (pmdevp->cur_power != cur_power) {
                        pmdevp->cur_power = cur_power;
                        if (pmdevp->sensorp) {
                                adjust_sensor_target(pmdevp->sensorp);
                                updated = 1;
                        }
                }
        }
        return (updated);
}

/*
 * Check if the specified sensor is present.
 * Returns 1 if present; 0 otherwise.
 *
 * Note that we don't use ptree_get_node_by_path() here to detect
 * if a temperature device is present as we don't want to make
 * "devtree" a critical plugin.
 */
static int
envd_sensor_present(env_sensor_t *sensorp)
{
        char            *p, physpath[PATH_MAX];
        di_node_t       root_node;
        int             sensor_present = 0;

        /*
         * Construct temperature device path by stripping minor
         * node name from the devfs_path and use di_init() to
         * see if the node exists.
         */
        (void) strcpy(physpath, sensorp->devfs_path);
        p = strrchr(physpath, ':');
        if (p != NULL)
                *p = '\0';
        if ((root_node = di_init(physpath, DINFOMINOR)) != DI_NODE_NIL) {
                di_fini(root_node);
                sensor_present = 1;
        }
        return (sensor_present);
}

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

        for (sensorp = &envd_sensors[0]; sensorp->name != NULL; sensorp++) {
                if (sensorp->fd != -1) {
                        /* Don't reinitialize opened sensor */
                        threshp = sensorp->temp_thresh;
                        sensorp->pmdevp = NULL;
                } else {
                        /* Initialize sensor's initial state */
                        sensorp->shutdown_initiated = B_FALSE;
                        sensorp->warning_tstamp = 0;
                        sensorp->warning_start = 0;
                        sensorp->shutdown_tstamp = 0;
                        sensorp->pmdevp = NULL;
                        sensorp->fan_adjustment_rate = 1.0;

                        threshp = sensorp->temp_thresh;
                        temp = (threshp && threshp->policy_entries > 0) ?
                            threshp->policy_data[0] : 0;
                        sensorp->target_temp = temp;
                        sensorp->cur_temp = temp;
                        sensorp->avg_temp = temp;
                        sensorp->prev_avg_temp = temp;
                        sensorp->error = 0;

                        (void) strcpy(path, "/devices");
                        (void) strlcat(path, sensorp->devfs_path,
                            sizeof (path));
                retry:
                        sensorp->fd = open(path, O_RDWR);
                        if (sensorp->fd == -1) {
                                sensor_present = envd_sensor_present(sensorp);
                                if (sensor_present && !devfsadm_invoked &&
                                    devfsadm_cmd[0] != '\0') {
                                        /*
                                         * Sensor is present but no path
                                         * exists as someone rebooted the
                                         * system without "-r" option. Let's
                                         * invoke "devfsadm" once to create
                                         * max1617 sensors paths in /devices
                                         * subtree and try again so that we
                                         * can monitor all accessible sensors
                                         * and prevent any CPU overheating.
                                         *
                                         * Note that this routine is always
                                         * called in main thread context and
                                         * serialized with respect to other
                                         * plugins' initialization. Hence, it's
                                         * safe to use system(3C) call here.
                                         */
                                        devfsadm_invoked = 1;
                                        (void) system(devfsadm_cmd);
                                        goto retry;
                                }
                                if (sensor_present)
                                        envd_log(LOG_CRIT,
                                            ENV_SENSOR_OPEN_FAIL,
                                            sensorp->name,
                                            sensorp->devfs_path, errno,
                                            strerror(errno));
                                sensorp->present = B_FALSE;
                                continue;
                        }
                        (void) fcntl(sensorp->fd, F_SETFD, FD_CLOEXEC);
                        sensorp->present = B_TRUE;

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

                /*
                 * Set low_power_off and high_power_off limits
                 */
                if (threshp && !disable_power_off) {
                        temp = xlate_exp2obs(sensorp, threshp->low_power_off);
                        if (env_debug > 1)
                                envd_log(LOG_INFO, "sensor: %-13s low_power_"
                                "off set to %d (real %d)\n", sensorp->name,
                                    (int)temp, threshp->low_power_off);
                        (void) ioctl(sensorp->fd, MAX1617_SET_LOW_LIMIT, &temp);

                        temp = xlate_exp2obs(sensorp, threshp->high_power_off);
                        if (env_debug > 1)
                                envd_log(LOG_INFO, "sensor: %-13s high_power_"
                                "off set to %d (real %d)\n", sensorp->name,
                                    (int)temp, threshp->high_power_off);
                        (void) ioctl(sensorp->fd, MAX1617_SET_HIGH_LIMIT,
                            &temp);
                }
        }

        /*
         * Locate "CPU Speed" component for any PM devices associated with
         * the sensors.
         */
        for (pmdevp = sensor_pmdevs; pmdevp->sensor_name; pmdevp++) {
                int             i, ncomp;
                char            physpath[PATH_MAX];
                pm_req_t        pmreq;

                pmdevp->speed_comp = -1;
                pmdevp->full_power = -1;
                pmdevp->cur_power = -1;
                pmdevp->next = NULL;
                pmdevp->sensorp = sensorp = sensor_lookup(pmdevp->sensor_name);

                /*
                 * Lookup speed component and get full and current power
                 * level for that component.
                 */
                pmreq.physpath = pmdevp->pmdev_name;
                pmreq.data = physpath;
                pmreq.datasize = sizeof (physpath);

                ncomp = ioctl(pm_fd, PM_GET_NUM_COMPONENTS, &pmreq);
                for (i = 0; i < ncomp; i++) {
                        pmreq.component = i;
                        physpath[0] = '\0';
                        if (ioctl(pm_fd, PM_GET_COMPONENT_NAME, &pmreq) <= 0)
                                continue;
                        if (strcasecmp(pmreq.data, pmdevp->speed_comp_name))
                                continue;
                        pmdevp->speed_comp = i;


                        /*
                         * Get full power and current power level
                         */
                        pmdevp->full_power = ioctl(pm_fd, PM_GET_FULL_POWER,
                            &pmreq);

                        pmdevp->cur_power = ioctl(pm_fd, PM_GET_CURRENT_POWER,
                            &pmreq);

                        if (sensorp) {
                                pmdevp->next = sensorp->pmdevp;
                                sensorp->pmdevp = pmdevp;
                                adjust_sensor_target(sensorp);
                        }
                        break;
                }
                if (env_debug > 1)
                        envd_log(LOG_INFO,
                            "sensor:%s %p pmdev:%s comp:%s %d power:%d/%d\n",
                            pmdevp->sensor_name, pmdevp->sensorp,
                            pmdevp->pmdev_name, pmdevp->speed_comp_name,
                            pmdevp->speed_comp, pmdevp->cur_power,
                            pmdevp->full_power);
        }
        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;
        env_sensor_t    *sensorp;
        sensor_thresh_t *threshp;
        time_t          ct;
        char            msgbuf[BUFSIZ];
        char            syscmd[BUFSIZ];

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

                sensorp->prev_avg_temp = sensorp->avg_temp;
                sensorp->cur_temp = temp;
                sensorp->avg_temp = (sensorp->avg_temp + temp)/2;
                threshp = sensorp->temp_thresh;

                if (env_debug)
                        envd_log(LOG_INFO,
                        "sensor: %-13s temp  prev_avg:%6.2f  "
                        "cur:%d avg_temp:%6.2f power:%d/%d target:%d\n",
                            sensorp->name, sensorp->prev_avg_temp,
                            temp, sensorp->avg_temp, ((sensorp->pmdevp) ?
                            sensorp->pmdevp->cur_power : -1),
                            ((sensorp->pmdevp) ? sensorp->pmdevp->full_power :
                            -1), sensorp->target_temp);


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

                /*
                 * Check for the temperature in warning and shutdown range
                 * and take appropriate action.
                 */
                if (TEMP_IN_WARNING_RANGE(temp, threshp) && !disable_warning) {
                        /*
                         * Check if the temperature has been in warning
                         * range during last warning_duration interval.
                         * If so, the temperature is truly in warning
                         * range and we need to log a warning message,
                         * but no more than once every warning_interval
                         * seconds.
                         */
                        time_t  wtstamp = sensorp->warning_tstamp;

                        ct = (time_t)(gethrtime() / NANOSEC);
                        if (sensorp->warning_start == 0)
                                sensorp->warning_start = ct;
                        if (((ct - sensorp->warning_start) >=
                            warning_duration) && (wtstamp == 0 ||
                            (ct - wtstamp) >= warning_interval)) {
                                envd_log(LOG_CRIT, ENV_WARNING_MSG,
                                    sensorp->name, temp,
                                    threshp->low_warning,
                                    threshp->high_warning);
                                sensorp->warning_tstamp = ct;
                        }
                } else if (sensorp->warning_start != 0)
                        sensorp->warning_start = 0;

                if (TEMP_IN_SHUTDOWN_RANGE(temp, threshp) &&
                    !disable_shutdown) {
                        ct = (time_t)(gethrtime() / NANOSEC);
                        if (sensorp->shutdown_tstamp == 0)
                                sensorp->shutdown_tstamp = ct;

                        /*
                         * Shutdown the system if the temperature remains
                         * in the shutdown range for over shutdown_interval
                         * seconds.
                         */
                        if ((ct - 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_ALERT, 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_ALERT, syscmd);
                                        system_shutdown_started = B_TRUE;
                                        (void) system(syscmd);
                                }
                        }
                } else if (sensorp->shutdown_tstamp != 0)
                        sensorp->shutdown_tstamp = 0;
        }
}


/*
 * Adjust fan speed based upon the current temperature value of various
 * sensors affected by the specified fan.
 */
static int
adjust_fan_speed(env_fan_t *fanp, lpm_dev_t *devp)
{
        int             i;
        fanspeed_t      fanspeed;
        float           speed, cur_speed, new_speed, max_speed, min_speed;
        env_sensor_t    *sensorp;
        sensor_thresh_t *threshp;
        tempr_t         temp;
        float           avg_temp, tempdiff, targetdiff;
        int             av_ambient;
        int             amb_cnt;


        /*
         * Get current fan speed
         */
        if (get_fan_speed(fanp, &fanspeed) < 0)
                return (-1);
        cur_speed = fanp->cur_speed;
        if (fanspeed != (int)cur_speed)
                cur_speed = (float)fanspeed;

        /*
         * Calculate new fan speed for each sensor and pick the largest one.
         */
        min_speed = fanp->speed_min;
        max_speed = fanp->speed_max;
        speed = 0;
        av_ambient = 0;
        amb_cnt = 0;

        for (i = 0; i < fanp->sensor_cnt; i++) {
                sensorp = fanp->sensors[i];
                if (sensorp == NULL || sensorp->fd == -1 ||
                    sensorp->temp_thresh == NULL)
                        continue;

                temp = sensorp->cur_temp;
                avg_temp = sensorp->avg_temp;
                threshp = sensorp->temp_thresh;

                /*
                 * Note ambient temperatures to determine lpm for system fan
                 */
                if ((devp != NULL) &&
                    (sensorp->flags & SFLAG_CPU_AMB_SENSOR)) {
                        av_ambient += temp;
                        amb_cnt++;
                }

                /*
                 * If the current temperature is above the warning
                 * threshold, use max fan speed.
                 */
                if (temp >= threshp->high_warning) {
                        speed = max_speed;
                        break;
                } else if (temp <= threshp->low_warning) {
                        speed = min_speed;
                        break;
                }

                if (threshp->policy_type == POLICY_TARGET_TEMP) {
                        /*
                         * Try to achieve the desired target temperature.
                         * Calculate new fan speed based upon whether the
                         * temperature is rising, falling or steady state.
                         * Also take into consideration the current fan
                         * speed as well as the desired target temperature.
                         */
                        float   delta, speed_change;
                        float   multiplier;

                        targetdiff = avg_temp - sensorp->target_temp;
                        tempdiff = avg_temp - sensorp->prev_avg_temp;

                        if (tempdiff > AVG_TEMP_HYSTERESIS) {
                                /*
                                 * Temperature is rising. Increase fan
                                 * speed 0.5% for every 1C above the
                                 * (target - RISING_TEMP_MARGIN) limit.
                                 * Also take into consideration temperature
                                 * rising rate and the current fan speed.
                                 */
                                delta = max_speed * .005 *
                                    (RISING_TEMP_MARGIN + targetdiff);
                                if (delta <= 0)
                                        multiplier = 0;
                                else
                                        multiplier = tempdiff/4 +
                                            ((cur_speed < max_speed/2) ?
                                            2 : 1);
                        } else if (tempdiff < -AVG_TEMP_HYSTERESIS) {
                                /*
                                 * Temperature is falling. Decrease fan
                                 * speed 0.5% for every 1C below the
                                 * (target + FALLING_TEMP_MARGIN) limit.
                                 * Also take into consideration temperature
                                 * falling rate and the current fan speed.
                                 */
                                delta = -max_speed * .005 *
                                    (FALLING_TEMP_MARGIN - targetdiff);
                                if (delta >= 0)
                                        multiplier = 0;
                                else
                                        multiplier = -tempdiff/4 +
                                            ((cur_speed > max_speed/2) ?
                                            2 : 1);
                        } else {
                                /*
                                 * Temperature is changing very slowly.
                                 * Adjust fan speed by 0.4% for every 1C
                                 * below/above the target temperature.
                                 */
                                delta = max_speed * .004 * targetdiff;
                                multiplier = 1.0;
                        }


                        /*
                         * Enforece some bounds on multiplier and the
                         * speed change.
                         */
                        multiplier = MIN(multiplier, 3.0);
                        speed_change = delta * multiplier *
                            sensorp->fan_adjustment_rate;
                        speed_change = MIN(speed_change, fan_incr_limit);
                        speed_change = MAX(speed_change, -fan_decr_limit);
                        new_speed = cur_speed + speed_change;

                        if (env_debug > 1)
                                envd_log(LOG_INFO,
                                "sensor: %-8s temp/diff:%d/%3.1f  "
                                "target/diff:%d/%3.1f  change:%4.2f x "
                                "%4.2f x %4.2f speed %5.2f -> %5.2f\n",
                                    sensorp->name, temp, tempdiff,
                                    sensorp->target_temp, targetdiff, delta,
                                    multiplier, sensorp->fan_adjustment_rate,
                                    cur_speed, new_speed);
                } else if (threshp->policy_type == POLICY_LINEAR) {
                        /*
                         * Set fan speed linearly within the operating
                         * range specified by the policy_data[LOW_NOMINAL_LOC]
                         * and policy_data[HIGH_NOMINAL_LOC] threshold values.
                         * Fan speed is set to minimum value at LOW_NOMINAL
                         * and to maximum value at HIGH_NOMINAL value.
                         */
                        new_speed = min_speed + (max_speed - min_speed) *
                            (avg_temp - threshp->policy_data[LOW_NOMINAL_LOC])/
                            (threshp->policy_data[HIGH_NOMINAL_LOC] -
                            threshp->policy_data[LOW_NOMINAL_LOC]);
                        if (env_debug > 1)
                                envd_log(LOG_INFO,
                                "sensor: %-8s policy: linear, cur_speed %5.2f"\
                                " new_speed: %5.2f\n", sensorp->name, cur_speed,
                                    new_speed);
                } else {
                        new_speed = cur_speed;
                }
                speed = MAX(speed, new_speed);
        }

        /*
         * Adjust speed using lpm tables
         */
        if (amb_cnt > 0) {
                av_ambient = (av_ambient >= 0 ?
                        (int)(0.5 + (float)av_ambient/(float)amb_cnt):
                        (int)(-0.5 + (float)av_ambient/(float)amb_cnt));
                speed = MAX(speed, (fanspeed_t)get_lpm_speed(devp, av_ambient));
        }

        speed = MIN(speed, max_speed);
        speed = MAX(speed, min_speed);

        /*
         * Record and update fan speed, if different.
         */
        fanp->prev_speed = fanp->cur_speed;
        fanp->cur_speed = speed;
        if ((fanspeed_t)speed != fanspeed) {
                fanspeed = (fanspeed_t)speed;
                (void) set_fan_speed(fanp, fanspeed);
        }
        if (env_debug)
                envd_log(LOG_INFO,
                    "fan: %-16s speed cur:%6.2f  new:%6.2f\n",
                    fanp->name, fanp->prev_speed, fanp->cur_speed);

        return (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.
 */
/*ARGSUSED*/
static void *
envthr(void *args)
{
        env_sensor_t    *sensorp;
        fanspeed_t      fan_speed;
        env_fan_t       *pmfanp = &envd_psupply_fan;
        int             to;
        int             xwd = -1;

        for (sensorp = &envd_sensors[0]; sensorp->name != NULL;
            sensorp++) {
                if (sensorp->obs2exp_map)
                        (void) free(sensorp->obs2exp_map);
                sensorp->obs2exp_map = NULL;
                sensorp->obs2exp_cnt = 0;
        }

        /*
         * Process environmental segment data, if present,
         * in the FRU SEEPROM.
         */
        process_fru_envseg();

        /*
         * 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) {
                envd_close_pm();
                return (NULL);
        }

        to = 3 * sensor_poll_interval + 1;
        xwd = open(XCALWD_DEVFS, O_RDONLY);
        if (xwd < 0) {
                envd_log(LOG_CRIT, ENV_WATCHDOG_INIT_FAIL, errno,
                    strerror(errno));
        } else if (ioctl(xwd, XCALWD_STOPWATCHDOG) < 0 ||
            ioctl(xwd, XCALWD_STARTWATCHDOG, &to) < 0) {
                envd_log(LOG_CRIT, ENV_WATCHDOG_INIT_FAIL, errno,
                    strerror(errno));
                (void) close(xwd);
                xwd = -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();

        for (;;) {
                (void) pthread_rwlock_rdlock(&envd_rwlock);

                /*
                 * If no "pmthr" thread, then we need to update the
                 * current power level for all power managed deviecs
                 * so that we can determine correct target temperature.
                 */
                if (pmthr_exists == B_FALSE)
                        (void) update_pmdev_power();

                if (xwd >= 0)
                        (void) ioctl(xwd, XCALWD_KEEPALIVE);

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

                        /*
                         * Adjust CPU and system fan speed
                         */
                        if (envd_cpu_fan.forced_speed < 0)
                                (void) adjust_fan_speed(&envd_cpu_fan, NULL);
                        if (envd_system_fan.forced_speed < 0)
                                (void) adjust_fan_speed(&envd_system_fan,
                                        lpm_devices);

                        /*
                         * Turn off power supply fan if in lowest power state.
                         */
                        fan_speed = (cur_lpstate) ? pmfanp->speed_min :
                            pmfanp->speed_max;

                        if (env_debug)
                                envd_log(LOG_INFO,
                                "fan: %-16s speed cur:%6.2f  new:%6.2f "
                                "low-power:%d\n", pmfanp->name,
                                    (float)pmfanp->cur_speed,
                                    (float)fan_speed, cur_lpstate);

                        if (fan_speed != (fanspeed_t)pmfanp->cur_speed &&
                            set_fan_speed(pmfanp, fan_speed) == 0)
                                pmfanp->cur_speed = fan_speed;
                }
                (void) pthread_rwlock_unlock(&envd_rwlock);

                /*
                 * Wait for sensor_poll_interval seconds before polling
                 * again. Note that we use our own envd_sleep() routine
                 * as sleep() in POSIX thread library gets affected by
                 * the wall clock time being set back.
                 */
                (void) envd_sleep(sensor_poll_interval);
        }
        /*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.
 */
/*ARGSUSED*/
static void *
pmthr(void *args)
{
        pm_state_change_t       pmstate;
        char                    physpath[PATH_MAX];

        pmstate.physpath = physpath;
        pmstate.size = sizeof (physpath);
        cur_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);

                /*
                 * Update current PM state for the components we are
                 * tracking. In case of CPU devices, PM state change
                 * event can be generated even before the state change
                 * takes effect, hence we need to get the current state
                 * for all CPU devices every time and recalculate the
                 * target temperature. We do this once after consuming
                 * all the queued events.
                 */

                (void) pthread_rwlock_rdlock(&envd_rwlock);
                (void) update_pmdev_power();
                (void) pthread_rwlock_unlock(&envd_rwlock);
        }

        /*
         * We won't be able to monitor lowest power state any longer,
         * hence reset it.
         */
        cur_lpstate = 0;
        envd_log(LOG_ERR, PM_THREAD_EXITING, errno, strerror(errno));
        pmthr_exists = B_FALSE;
        return (NULL);
}


/*
 * Process sensor threshold related tuneables
 */
static int
process_threshold_tuneable(char *keyword, char *buf, void *dummy_thresh_addr,
    int flags, char *fname, int line)
{
        int             retval = 0;
        long            val;
        void            *addr;
        char            *endp, *sname;
        env_sensor_t    *sensorp;

        /*
         * Tuneable entry can be in one of the following formats:
         *
         *      threshold-keyword <int-value>
         *      threshold-keyword <int-value> <sensor-name> ...
         *
         * Convert threshold value into integer value and check for
         * optional sensor name. If no sensor name is specified, then
         * the tuneable applies to all sensors specified by the "flags".
         * Otherwise, it is applicable to the specified sensors.
         *
         * Note that the dummy_thresh_addr is the address of the threshold
         * to be changed and is converted into offset by subtracting the
         * base dummy_thresh address. This offset is added to the base
         * address of the threshold structure to be update to determine
         * the final memory address to be modified.
         */

        errno = 0;
        val = strtol(buf, &endp, 0);
        sname = strtok(endp, tokdel);

        if (errno != 0 || val != (tempr_t)val) {
                retval = -1;
                envd_log(LOG_INFO, ENV_CONF_INT_EXPECTED, fname, line, keyword);
        } else if (flags == 0 && sname == NULL) {
                envd_log(LOG_INFO, "SUNW_piclenvd: file:%s line:%d SKIPPED"
                    " as no sensor specified.\n", fname, line, keyword);
                retval = -1;
        } else if (sname == NULL) {
                int     cnt = 0;

                for (sensorp = &envd_sensors[0]; sensorp->name; sensorp++) {
                        if (sensorp->temp_thresh == NULL ||
                            (sensorp->flags & flags) == 0)
                                continue;

                        /*
                         * Convert dummy_thresh_addr into memory address
                         * for this sensor threshold values.
                         */
                        addr = (char *)sensorp->temp_thresh +
                            (int)((char *)dummy_thresh_addr -
                            (char *)&dummy_thresh);

                        *(tempr_t *)addr = (tempr_t)val;
                        cnt++;
                        if (env_debug)
                                envd_log(LOG_INFO, "SUNW_piclenvd: file:%s "
                                "line:%d %s = %d for sensor: '%s'\n",
                                    fname, line, keyword, val, sensorp->name);
                }
                if (cnt == 0)
                        envd_log(LOG_INFO, "SUNW_piclenvd: file:%s line:%d "
                        "%s SKIPPED as no matching sensor found.\n",
                            fname, line, keyword);
        } else {
                /* apply threshold value to the specified sensors */
                do {
                        sensorp = sensor_lookup(sname);
                        if (sensorp == NULL || sensorp->temp_thresh == NULL ||
                            (flags && (sensorp->flags & flags) == 0)) {
                                envd_log(LOG_INFO,
                                "SUNW_piclenvd: file:%s line:%d %s SKIPPED"
                                " for '%s' as not a valid sensor.\n",
                                    fname, line, keyword, sname);
                                continue;
                        }
                        /*
                         * Convert dummy_thresh_addr into memory address
                         * for this sensor threshold values.
                         */
                        addr = (char *)sensorp->temp_thresh +
                            (int)((char *)dummy_thresh_addr -
                            (char *)&dummy_thresh);

                        *(tempr_t *)addr = (tempr_t)val;
                        if (env_debug)
                                envd_log(LOG_INFO, "SUNW_piclenvd: file:%s "
                                "line:%d %s = %d for sensor: '%s'\n",
                                    fname, line, keyword, val, sensorp->name);
                } while ((sname = strtok(NULL, tokdel)) != NULL);
        }
        return (retval);
}


/*
 * Process integer tuneables
 */
static int
process_int_tuneable(char *keyword, char *buf, void *addr, int size,
    char *fname, int line)
{
        int     retval = 0;
        char    *endp;
        long    val;

        /*
         * Convert input into integer value and ensure that there is
         * no other token in the buffer.
         */
        errno = 0;
        val = strtol(buf, &endp, 0);
        if (errno != 0 || strtok(endp, tokdel) != NULL)
                retval = -1;
        else {
                switch (size) {
                case 1:
                        if (val != (int8_t)val)
                                retval = -1;
                        else
                                *(int8_t *)addr = (int8_t)val;
                        break;
                case 2:
                        if (val != (short)val)
                                retval = -1;
                        else
                                *(short *)addr = (short)val;
                        break;
                case 4:
                        *(int *)addr = (int)val;
                        break;
                default:
                        retval = -1;
                }
        }

        if (retval == -1)
                envd_log(LOG_INFO, ENV_CONF_INT_EXPECTED,
                    fname, line, keyword);
        else if (env_debug)
                envd_log(LOG_INFO, "SUNW_piclenvd: file:%s line:%d %s = %d\n",
                    fname, line, keyword, val);

        return (retval);
}


/*
 * Process string tuneables
 *
 * String value must be within double quotes.  Skip over initial white
 * spaces before looking for string value.
 */
static int
process_string_tuneable(char *keyword, char *buf, void *addr, int size,
    char *fname, int line)
{
        int     retval = 0;
        char    c, *p, *strend;

        /* Skip over white spaces */
        buf += strspn(buf, tokdel);

        /*
         * Parse srting and locate string end (handling escaped double quotes
         * and other characters)
         */
        if (buf[0] != '"')
                strend = NULL;
        else {
                for (p = buf+1; (c = *p) != '\0'; p++)
                        if (c == '"' || (c == '\\' && *++p == '\0'))
                                break;
                strend = (*p == '"') ? p : NULL;
        }

        if (strend == NULL || (strend-buf) > size ||
            strtok(strend+1, tokdel) != NULL) {
                envd_log(LOG_WARNING, ENV_CONF_STRING_EXPECTED,
                    fname, line, keyword, size);
                retval = -1;
        } else {
                *strend = '\0';
                (void) strcpy(addr, (caddr_t)buf+1);
                if (env_debug)
                        envd_log(LOG_INFO, "SUNW_piclenvd: file:%s line:%d "
                            "%s = \"%s\"\n", fname, line, keyword, buf+1);
        }

        return (retval);
}


/*
 * Process configuration file
 */
static void
process_env_conf_file(void)
{
        int             line, len, toklen;
        char            buf[BUFSIZ];
        FILE            *fp;
        env_tuneable_t  *tunep;
        char            nmbuf[SYS_NMLN];
        char            fname[PATH_MAX];
        char            *tok, *valuep;
        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 (strcasecmp(tunep->name, tok) == 0) {
                                (void) (*tunep->func)(tok, valuep,
                                    tunep->arg1, tunep->arg2, fname, line);
                                break;
                        }
                }

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

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

static int
envd_setup(void)
{
        char            *valp, *endp;
        int             val;
        int             err;

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

        if (pm_fd == -1)
                envd_open_pm();

        /*
         * Setup lpm devices
         */
        lpm_devices = NULL;
        if ((err = setup_lpm_devices(&lpm_devices)) != PICL_SUCCESS) {
                if (env_debug)
                        envd_log(LOG_ERR, "setup_lpm_devices failed err = %d\n",
                                err);
        }

        /*
         * Initialize global state to initial startup values
         */
        sensor_poll_interval = SENSOR_POLL_INTERVAL;
        fan_slow_adjustment = FAN_SLOW_ADJUSTMENT;
        fan_incr_limit = FAN_INCREMENT_LIMIT;
        fan_decr_limit = FAN_DECREMENT_LIMIT;
        warning_interval = WARNING_INTERVAL;
        warning_duration = WARNING_DURATION;
        shutdown_interval = SHUTDOWN_INTERVAL;
        disable_piclenvd = 0;
        disable_power_off = 0;
        disable_shutdown = 0;
        disable_warning = 0;

        (void) strlcpy(shutdown_cmd, SHUTDOWN_CMD, sizeof (shutdown_cmd));
        (void) strlcpy(devfsadm_cmd, DEVFSADM_CMD, sizeof (devfsadm_cmd));
        (void) strlcpy(fru_devfsadm_cmd, FRU_DEVFSADM_CMD,
            sizeof (fru_devfsadm_cmd));
        envd_cpu_fan.forced_speed = -1;
        envd_system_fan.forced_speed = -1;

        (void) memcpy(&cpu0_die_thresh, &cpu_die_thresh_default,
            sizeof (cpu_die_thresh_default));
        (void) memcpy(&cpu0_amb_thresh, &cpu_amb_thresh_default,
            sizeof (cpu_amb_thresh_default));
        (void) memcpy(&cpu1_die_thresh, &cpu_die_thresh_default,
            sizeof (cpu_die_thresh_default));
        (void) memcpy(&cpu1_amb_thresh, &cpu_amb_thresh_default,
            sizeof (cpu_amb_thresh_default));

        if ((valp = getenv("SUNW_piclenvd_debug")) != NULL) {
                val = strtol(valp, &endp, 0);
                if (strtok(endp, tokdel) == NULL)
                        env_debug = val;
        }

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

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

/*
 * Callback function used by ptree_walk_tree_by_class for the cpu class
 */
static int
cb_cpu(picl_nodehdl_t nodeh, void *args)
{
        sensor_pmdev_t          *pmdevp;
        int                     err;
        ptree_propinfo_t        pinfo;
        picl_prophdl_t          proph;
        size_t                  psize;
        int                     id;

        /* Get CPU's ID, it is an int */
        err = ptree_get_propval_by_name(nodeh, PICL_PROP_ID, &id, sizeof (int));
        if (err != PICL_SUCCESS)
                return (PICL_WALK_CONTINUE);

        /* Get the pmdevp for the CPU */
        pmdevp = sensor_pmdevs;
        while (pmdevp->sensor_id != -1) {
                if (id == pmdevp->sensor_id)
                        break;
                pmdevp++;
        }

        /* Return if didn't find the pmdevp for the cpu id */
        if (pmdevp->sensor_id == -1)
                return (PICL_WALK_CONTINUE);

        /* Get the devfs-path property */
        err = ptree_get_prop_by_name(nodeh, PICL_PROP_DEVFS_PATH, &proph);
        if (err != PICL_SUCCESS)
                return (PICL_WALK_CONTINUE);

        err = ptree_get_propinfo(proph, &pinfo);
        if ((err != PICL_SUCCESS) ||
            (pinfo.piclinfo.type != PICL_PTYPE_CHARSTRING))
                return (PICL_WALK_CONTINUE);

        psize = pinfo.piclinfo.size;
        pmdevp->pmdev_name = malloc(psize);
        if (pmdevp->pmdev_name == NULL)
                return (PICL_WALK_CONTINUE);

        err = ptree_get_propval(proph, pmdevp->pmdev_name, psize);
        if (err != PICL_SUCCESS)
                return (PICL_WALK_CONTINUE);

        return (PICL_WALK_CONTINUE);
}

/*
 * Find the CPU's in the picl tree, set the devfs-path for pmdev_name
 */
static void
setup_pmdev_names()
{
        picl_nodehdl_t  plath;
        int             err;

        err = ptree_get_node_by_path(PLATFORM_PATH, &plath);
        if (err != PICL_SUCCESS)
                return;

        err = ptree_walk_tree_by_class(plath, PICL_CLASS_CPU, NULL, cb_cpu);
}


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

static void
piclenvd_init(void)
{
        /*
         * Setup the names for the pm sensors, we do it just the first time
         */
        if (pmdev_names_init == B_FALSE) {
                (void) setup_pmdev_names();
                pmdev_names_init = B_TRUE;
        }

        /*
         * Start environmental monitor/threads
         */
        (void) pthread_rwlock_wrlock(&envd_rwlock);
        if (envd_setup() != 0) {
                (void) pthread_rwlock_unlock(&envd_rwlock);
                envd_log(LOG_CRIT, ENVD_PLUGIN_INIT_FAILED);
                return;
        }
        (void) pthread_rwlock_unlock(&envd_rwlock);

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

static void
piclenvd_fini(void)
{
        /*
         * Delete the lpm device list. After this the lpm information
         * will not be used in determining the fan speed, till the lpm
         * device information is initialized by setup_lpm_devices called
         * by envd_setup.
         */
        delete_lpm_devices();

        /*
         * Invoke env_picl_destroy() to remove any PICL nodes/properties
         * (including volatile properties) we created. Once this call
         * returns, there can't be any more calls from the PICL framework
         * to get current temperature or fan speed.
         */
        env_picl_destroy();

        /*
         * Since this is a critical plug-in, we know that it won't be
         * unloaded and will be reinited again unless picld process is
         * going away. Therefore, it's okay to let "envthr" and "pmthr"
         * continue so that we can monitor the environment during SIGHUP
         * handling also.
         */
}

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

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


/*
 * sleep() in libpthread gets affected by time being set back, hence
 * can cause the "envthr" not to wakeup for extended duration. For
 * now, we implement our own sleep() routine below using alarm().
 * This will work only if SIGALRM is masked off in all other threads.
 * Note that SIGALRM signal is masked off in the main thread, hence
 * in all threads, including the envthr, the one calling this routine.
 *
 * Note that SIGALRM and alarm() can't be used by any other thread
 * in this manner.
 */

static unsigned int
envd_sleep(unsigned int sleep_tm)
{
        int             sig;
        unsigned int    unslept;
        sigset_t        alrm_mask;

        if (sleep_tm == 0)
                return (0);

        (void) sigemptyset(&alrm_mask);
        (void) sigaddset(&alrm_mask, SIGALRM);

        (void) alarm(sleep_tm);
        (void) sigwait(&alrm_mask, &sig);

        unslept = alarm(0);
        return (unslept);
}