/*      $OpenBSD: viapm.c,v 1.23 2024/05/24 06:02:58 jsg Exp $  */

/*
 * Copyright (c) 2005 Mark Kettenis <kettenis@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*      $NetBSD: viaenv.c,v 1.9 2002/10/02 16:51:59 thorpej Exp $       */

/*
 * Copyright (c) 2000 Johan Danielsson
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of author nor the names of any contributors may
 *    be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Driver for the SMBus controller and power management timer
 * in the VIA VT82C596[B], VT82C686A, VT8231, VT8233[A], VT8235, VT8237[A,S],
 * VT8251, CX700, VX800, VX855 and VX900 South Bridges.
 * Also for the hardware monitoring part of the VIA VT82C686A and VT8231.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/rwlock.h>
#include <sys/sensors.h>
#include <sys/timeout.h>
#include <sys/timetc.h>

#include <machine/bus.h>

#include <dev/pci/pcidevs.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>

#include <dev/i2c/i2cvar.h>

/*
 * Register definitions.
 */

/* PCI configuration registers */
#define VIAPM_PM_CFG1           0x40    /* general configuration */
#define VIAPM_PM_CFG2           0x80
#define VIAPM_PM_CFG_TMR32      (1 << 11)       /* 32-bit PM timer */
#define VIAPM_PM_CFG_PMEN       (1 << 15)       /* enable PM I/O space */
#define VIAPM_PM_BASE1          0x48    /* power management I/O base address */
#define VIAPM_PM_BASE2          0x88
#define VIAPM_PM_BASE_MASK      0xff80

#define VIAPM_HWMON_BASE        0x70    /* HWMon I/O base address */
#define VIAPM_HWMON_BASE_MASK   0xff80
#define VIAPM_HWMON_CFG         0x74    /* HWMon control register */
#define VIAPM_HWMON_CFG_HWEN    (1 << 0)        /* enable HWMon I/O space */

#define VIAPM_SMB_BASE1         0x90    /* SMBus I/O base address */
#define VIAPM_SMB_BASE2         0x80
#define VIAPM_SMB_BASE3         0xd0
#define VIAPM_SMB_BASE_MASK     0xfff0
#define VIAPM_SMB_CFG1          0xd2    /* host configuration */
#define VIAPM_SMB_CFG2          0x84
#define VIAPM_SMB_CFG_HSTEN     (1 << 0)        /* enable SMBus I/O space */
#define VIAPM_SMB_CFG_INTEN     (1 << 1)        /* enable SCI/SMI */
#define VIAPM_SMB_CFG_SCIEN     (1 << 3)        /* interrupt type (SCI/SMI) */

#define VIAPM_PM_SIZE           256     /* Power management I/O space size */
#define VIAPM_HWMON_SIZE        128     /* HWMon I/O space size */
#define VIAPM_SMB_SIZE          16      /* SMBus I/O space size */

/* HWMon I/O registers */
#define VIAPM_HWMON_TSENS3      0x1f
#define VIAPM_HWMON_TSENS1      0x20
#define VIAPM_HWMON_TSENS2      0x21
#define VIAPM_HWMON_VSENS1      0x22
#define VIAPM_HWMON_VSENS2      0x23
#define VIAPM_HWMON_VCORE       0x24
#define VIAPM_HWMON_VSENS3      0x25
#define VIAPM_HWMON_VSENS4      0x26
#define VIAPM_HWMON_FAN1        0x29
#define VIAPM_HWMON_FAN2        0x2a
#define VIAPM_HWMON_FANCONF     0x47    /* fan configuration */
#define VIAPM_HWMON_TLOW        0x49    /* temperature low order value */
#define VIAPM_HWMON_TIRQ        0x4b    /* temperature interrupt configuration */

/* ACPI I/O registers */
#define VIAPM_PM_TMR            0x08    /* PM timer */

/* SMBus I/O registers */
#define VIAPM_SMB_HS            0x00    /* host status */
#define VIAPM_SMB_HS_BUSY       (1 << 0)        /* running a command */
#define VIAPM_SMB_HS_INTR       (1 << 1)        /* command completed */
#define VIAPM_SMB_HS_DEVERR     (1 << 2)        /* command error */
#define VIAPM_SMB_HS_BUSERR     (1 << 3)        /* transaction collision */
#define VIAPM_SMB_HS_FAILED     (1 << 4)        /* failed bus transaction */
#define VIAPM_SMB_HS_INUSE      (1 << 6)        /* bus semaphore */
#define VIAPM_SMB_HS_BITS       \
  "\020\001BUSY\002INTR\003DEVERR\004BUSERR\005FAILED\007INUSE"
#define VIAPM_SMB_HC            0x02    /* host control */
#define VIAPM_SMB_HC_INTREN     (1 << 0)        /* enable interrupts */
#define VIAPM_SMB_HC_KILL       (1 << 1)        /* kill current transaction */
#define VIAPM_SMB_HC_CMD_QUICK  (0 << 2)        /* QUICK command */
#define VIAPM_SMB_HC_CMD_BYTE   (1 << 2)        /* BYTE command */
#define VIAPM_SMB_HC_CMD_BDATA  (2 << 2)        /* BYTE DATA command */
#define VIAPM_SMB_HC_CMD_WDATA  (3 << 2)        /* WORD DATA command */
#define VIAPM_SMB_HC_CMD_PCALL  (4 << 2)        /* PROCESS CALL command */
#define VIAPM_SMB_HC_CMD_BLOCK  (5 << 2)        /* BLOCK command */
#define VIAPM_SMB_HC_START      (1 << 6)        /* start transaction */
#define VIAPM_SMB_HCMD          0x03    /* host command */
#define VIAPM_SMB_TXSLVA        0x04    /* transmit slave address */
#define VIAPM_SMB_TXSLVA_READ   (1 << 0)        /* read direction */
#define VIAPM_SMB_TXSLVA_ADDR(x) (((x) & 0x7f) << 1) /* 7-bit address */
#define VIAPM_SMB_HD0           0x05    /* host data 0 */
#define VIAPM_SMB_HD1           0x06    /* host data 1 */
#define VIAPM_SMB_HBDB          0x07    /* host block data byte */

#ifdef VIAPM_DEBUG
#define DPRINTF(x...) printf(x)
#else
#define DPRINTF(x...)
#endif

#define DEVNAME(sc) ((sc)->sc_dev.dv_xname)

#define VIAPM_SMBUS_DELAY       100
#define VIAPM_SMBUS_TIMEOUT     1

#define VIAPM_NUM_SENSORS       10      /* three temp, two fan, five voltage */

u_int   viapm_get_timecount(struct timecounter *tc);

#ifndef VIAPM_FREQUENCY
#define VIAPM_FREQUENCY 3579545
#endif

static struct timecounter viapm_timecounter = {
        .tc_get_timecount = viapm_get_timecount,
        .tc_counter_mask = 0xffffff,
        .tc_frequency = VIAPM_FREQUENCY,
        .tc_name = "VIAPM",
        .tc_quality = 1000,
        .tc_priv = NULL,
        .tc_user = 0,
};

struct timeout viapm_timeout;

struct viapm_softc {
        struct device           sc_dev;

        bus_space_tag_t         sc_iot;
        bus_space_handle_t      sc_pm_ioh;
        bus_space_handle_t      sc_smbus_ioh;
        bus_space_handle_t      sc_hwmon_ioh;
        void *                  sc_ih;
        int                     sc_poll;

        int                     sc_fan_div[2];  /* fan RPM divisor */

        struct ksensor          sc_data[VIAPM_NUM_SENSORS];
        struct ksensordev       sc_sensordev;

        struct i2c_controller   sc_i2c_tag;
        struct rwlock           sc_i2c_lock;
        struct {
                i2c_op_t     op;
                void *       buf;
                size_t       len;
                int          flags;
                volatile int error;
        }                       sc_i2c_xfer;
};

int     viapm_match(struct device *, void *, void *);
void    viapm_attach(struct device *, struct device *, void *);

int     viapm_i2c_acquire_bus(void *, int);
void    viapm_i2c_release_bus(void *, int);
int     viapm_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
            void *, size_t, int);

int     viapm_intr(void *);

int     val_to_uK(unsigned int);
int     val_to_rpm(unsigned int, int);
long    val_to_uV(unsigned int, int);
void    viapm_refresh_sensor_data(struct viapm_softc *);
void    viapm_refresh(void *);

const struct cfattach viapm_ca = {
        sizeof(struct viapm_softc), viapm_match, viapm_attach
};

struct cfdriver viapm_cd = {
        NULL, "viapm", DV_DULL
};

const struct pci_matchid viapm_ids[] = {
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT82C596 },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT82C596B_PM },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT82C686A_SMB },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8231_PWR },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8233_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8233A_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8235_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8237_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8237A_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8237S_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VT8251_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_CX700_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VX800_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VX855_ISA },
        { PCI_VENDOR_VIATECH, PCI_PRODUCT_VIATECH_VX900_ISA }
};

/*
 * XXX there doesn't seem to exist much hard documentation on how to
 * convert the raw values to usable units, this code is more or less
 * stolen from the Linux driver, but changed to suit our conditions
 */

/*
 * lookup-table to translate raw values to uK, this is the same table
 * used by the Linux driver (modulo units); there is a fifth degree
 * polynomial that supposedly been used to generate this table, but I
 * haven't been able to figure out how -- it doesn't give the same values
 */

static const long val_to_temp[] = {
        20225, 20435, 20645, 20855, 21045, 21245, 21425, 21615, 21785, 21955,
        22125, 22285, 22445, 22605, 22755, 22895, 23035, 23175, 23315, 23445,
        23565, 23695, 23815, 23925, 24045, 24155, 24265, 24365, 24465, 24565,
        24665, 24765, 24855, 24945, 25025, 25115, 25195, 25275, 25355, 25435,
        25515, 25585, 25655, 25725, 25795, 25865, 25925, 25995, 26055, 26115,
        26175, 26235, 26295, 26355, 26405, 26465, 26515, 26575, 26625, 26675,
        26725, 26775, 26825, 26875, 26925, 26975, 27025, 27065, 27115, 27165,
        27205, 27255, 27295, 27345, 27385, 27435, 27475, 27515, 27565, 27605,
        27645, 27685, 27735, 27775, 27815, 27855, 27905, 27945, 27985, 28025,
        28065, 28105, 28155, 28195, 28235, 28275, 28315, 28355, 28405, 28445,
        28485, 28525, 28565, 28615, 28655, 28695, 28735, 28775, 28825, 28865,
        28905, 28945, 28995, 29035, 29075, 29125, 29165, 29205, 29245, 29295,
        29335, 29375, 29425, 29465, 29505, 29555, 29595, 29635, 29685, 29725,
        29765, 29815, 29855, 29905, 29945, 29985, 30035, 30075, 30125, 30165,
        30215, 30255, 30305, 30345, 30385, 30435, 30475, 30525, 30565, 30615,
        30655, 30705, 30755, 30795, 30845, 30885, 30935, 30975, 31025, 31075,
        31115, 31165, 31215, 31265, 31305, 31355, 31405, 31455, 31505, 31545,
        31595, 31645, 31695, 31745, 31805, 31855, 31905, 31955, 32005, 32065,
        32115, 32175, 32225, 32285, 32335, 32395, 32455, 32515, 32575, 32635,
        32695, 32755, 32825, 32885, 32955, 33025, 33095, 33155, 33235, 33305,
        33375, 33455, 33525, 33605, 33685, 33765, 33855, 33935, 34025, 34115,
        34205, 34295, 34395, 34495, 34595, 34695, 34805, 34905, 35015, 35135,
        35245, 35365, 35495, 35615, 35745, 35875, 36015, 36145, 36295, 36435,
        36585, 36745, 36895, 37065, 37225, 37395, 37575, 37755, 37935, 38125,
        38325, 38525, 38725, 38935, 39155, 39375, 39605, 39835, 40075, 40325,
        40575, 40835, 41095, 41375, 41655, 41935,
};

int
viapm_match(struct device *parent, void *match, void *aux)
{
        return (pci_matchbyid(aux, viapm_ids, nitems(viapm_ids)));
}

void
viapm_attach(struct device *parent, struct device *self, void *aux)
{
        struct viapm_softc *sc = (struct viapm_softc *)self;
        struct pci_attach_args *pa = aux;
        struct i2cbus_attach_args iba;
        pcireg_t conf, iobase;
        pci_intr_handle_t ih;
        const char *intrstr = NULL;
        int basereg, cfgreg;
        int i, v;

        sc->sc_iot = pa->pa_iot;

        /* SMBus */
        switch (PCI_PRODUCT(pa->pa_id)) {
        case PCI_PRODUCT_VIATECH_VT82C596:
        case PCI_PRODUCT_VIATECH_VT82C596B_PM:
        case PCI_PRODUCT_VIATECH_VT82C686A_SMB:
        case PCI_PRODUCT_VIATECH_VT8231_PWR:
                basereg = VIAPM_SMB_BASE1;
                break;
        default:
                basereg = VIAPM_SMB_BASE3;
        }

        cfgreg = (VIAPM_SMB_CFG1 & (~0x03));    /* XXX 4-byte aligned */

        /* Check 2nd address for VT82C596 */
        iobase = pci_conf_read(pa->pa_pc, pa->pa_tag, basereg);
        if ((PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_VIATECH_VT82C596) &&
            ((iobase & 0x0001) == 0)) {
                iobase = pci_conf_read(pa->pa_pc, pa->pa_tag, VIAPM_SMB_BASE2);
                cfgreg = VIAPM_SMB_CFG2;
        }

        /* Check if SMBus I/O space is enabled */
        conf = pci_conf_read(pa->pa_pc, pa->pa_tag, cfgreg);
        if (cfgreg != VIAPM_SMB_CFG2)
                conf >>= 16;
        DPRINTF(": conf 0x%02x", conf & 0xff);

        if ((conf & VIAPM_SMB_CFG_HSTEN) == 0) {
                printf(": SMBus disabled\n");
                goto nosmb;
        }

        /* Map SMBus I/O space */
        iobase &= VIAPM_SMB_BASE_MASK;
        if (iobase == 0 || bus_space_map(sc->sc_iot, iobase,
            VIAPM_SMB_SIZE, 0, &sc->sc_smbus_ioh)) {
                printf(": can't map SMBus i/o space\n");
                goto nosmb;
        }

        sc->sc_poll = 1;
        if ((conf & VIAPM_SMB_CFG_SCIEN) == 0) {
                /* No PCI IRQ */
                printf(": SMI");
        } else {
                /* Install interrupt handler */
                if (pci_intr_map(pa, &ih) == 0) {
                        intrstr = pci_intr_string(pa->pa_pc, ih);
                        sc->sc_ih = pci_intr_establish(pa->pa_pc, ih, IPL_BIO,
                            viapm_intr, sc, DEVNAME(sc));
                        if (sc->sc_ih != NULL) {
                                printf(": %s", intrstr);
                                sc->sc_poll = 0;
                        }
                }
                if (sc->sc_poll)
                        printf(": polling");
        }

        printf("\n");

        /* Attach I2C bus */
        rw_init(&sc->sc_i2c_lock, "iiclk");
        sc->sc_i2c_tag.ic_cookie = sc;
        sc->sc_i2c_tag.ic_acquire_bus = viapm_i2c_acquire_bus;
        sc->sc_i2c_tag.ic_release_bus = viapm_i2c_release_bus;
        sc->sc_i2c_tag.ic_exec = viapm_i2c_exec;

        bzero(&iba, sizeof iba);
        iba.iba_name = "iic";
        iba.iba_tag = &sc->sc_i2c_tag;
        config_found(self, &iba, iicbus_print);

nosmb:

        /* Power management */
        switch (PCI_PRODUCT(pa->pa_id)) {
        case PCI_PRODUCT_VIATECH_VT82C596:
        case PCI_PRODUCT_VIATECH_VT82C596B_PM:
        case PCI_PRODUCT_VIATECH_VT82C686A_SMB:
        case PCI_PRODUCT_VIATECH_VT8231_PWR:
                basereg = VIAPM_PM_BASE1;
                cfgreg = VIAPM_PM_CFG1;
                break;
        default:
                basereg = VIAPM_PM_BASE2;
                cfgreg = VIAPM_PM_CFG2;
        }

        /* Check if power management I/O space is enabled */
        conf = pci_conf_read(pa->pa_pc, pa->pa_tag, cfgreg);
        if ((conf & VIAPM_PM_CFG_PMEN) == 0) {
                printf("%s: PM disabled\n", DEVNAME(sc));
                goto nopm;
        }

        /* Map power management I/O space */
        iobase = pci_conf_read(pa->pa_pc, pa->pa_tag, basereg);
        iobase &= VIAPM_PM_BASE_MASK;
        if (iobase == 0 || bus_space_map(sc->sc_iot, iobase,
            VIAPM_PM_SIZE, 0, &sc->sc_pm_ioh)) {
                /* XXX can't map PM i/o space if ACPI mode */
                DPRINTF("%s: can't map PM i/o space\n", DEVNAME(sc));
                goto nopm;
        }

        /* Check for 32-bit PM timer */
        if (conf & VIAPM_PM_CFG_TMR32)
                viapm_timecounter.tc_counter_mask = 0xffffffff;

        /* Register new timecounter */
        viapm_timecounter.tc_priv = sc;
        tc_init(&viapm_timecounter);

        printf("%s: %s-bit timer at %lluHz\n", DEVNAME(sc),
            (viapm_timecounter.tc_counter_mask == 0xffffffff ? "32" : "24"),
            (unsigned long long)viapm_timecounter.tc_frequency);

nopm:

        /* HWMon */
        switch (PCI_PRODUCT(pa->pa_id)) {
        case PCI_PRODUCT_VIATECH_VT82C686A_SMB:
        case PCI_PRODUCT_VIATECH_VT8231_PWR:
                break;
        default:
                return;
        }

        /* Check if HWMon I/O space is enabled */
        conf = pci_conf_read(pa->pa_pc, pa->pa_tag, VIAPM_HWMON_CFG);
        if ((conf & VIAPM_HWMON_CFG_HWEN) == 0) {
                printf("%s: HWM disabled\n", DEVNAME(sc));
                return;
        }

        /* Map HWMon I/O space */
        iobase = pci_conf_read(pa->pa_pc, pa->pa_tag, VIAPM_HWMON_BASE);
        iobase &= VIAPM_HWMON_BASE_MASK;
        if (iobase == 0 || bus_space_map(sc->sc_iot, iobase,
            VIAPM_HWMON_SIZE, 0, &sc->sc_hwmon_ioh)) {
                printf("%s: can't map HWM i/o space\n", DEVNAME(sc));
                return;
        }

        v = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh, VIAPM_HWMON_FANCONF);

        sc->sc_fan_div[0] = 1 << ((v >> 4) & 0x3);
        sc->sc_fan_div[1] = 1 << ((v >> 6) & 0x3);

        for (i = 0; i <= 2; i++)
                sc->sc_data[i].type = SENSOR_TEMP;
        for (i = 3; i <= 4; i++)
                sc->sc_data[i].type = SENSOR_FANRPM;
        for (i = 5; i <= 9; ++i)
                sc->sc_data[i].type = SENSOR_VOLTS_DC;

        strlcpy(sc->sc_data[5].desc, "VSENS1",
            sizeof(sc->sc_data[5].desc));       /* CPU core (2V) */
        strlcpy(sc->sc_data[6].desc, "VSENS2",
            sizeof(sc->sc_data[6].desc));       /* NB core? (2.5V) */
        strlcpy(sc->sc_data[7].desc, "Vcore",
            sizeof(sc->sc_data[7].desc));       /* Vcore (3.3V) */
        strlcpy(sc->sc_data[8].desc, "VSENS3",
            sizeof(sc->sc_data[8].desc));       /* VSENS3 (5V) */
        strlcpy(sc->sc_data[9].desc, "VSENS4",
            sizeof(sc->sc_data[9].desc));       /* VSENS4 (12V) */

        /* Get initial set of sensor values. */
        viapm_refresh_sensor_data(sc);

        /* Register sensors with sysctl */
        strlcpy(sc->sc_sensordev.xname, DEVNAME(sc),
            sizeof(sc->sc_sensordev.xname));
        for (i = 0; i < VIAPM_NUM_SENSORS; ++i)
                sensor_attach(&sc->sc_sensordev, &sc->sc_data[i]);
        sensordev_install(&sc->sc_sensordev);

        /* Refresh sensors data every 1.5 seconds */
        timeout_set(&viapm_timeout, viapm_refresh, sc);
        timeout_add_msec(&viapm_timeout, 1500);
}

int
viapm_i2c_acquire_bus(void *cookie, int flags)
{
        struct viapm_softc *sc = cookie;

        if (cold || sc->sc_poll || (flags & I2C_F_POLL))
                return (0);

        return (rw_enter(&sc->sc_i2c_lock, RW_WRITE | RW_INTR));
}

void
viapm_i2c_release_bus(void *cookie, int flags)
{
        struct viapm_softc *sc = cookie;

        if (cold || sc->sc_poll || (flags & I2C_F_POLL))
                return;

        rw_exit(&sc->sc_i2c_lock);
}

int
viapm_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr,
    const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags)
{
        struct viapm_softc *sc = cookie;
        u_int8_t *b;
        u_int8_t ctl, st;
        int retries;

        /* Check if there's a transfer already running */
        st = bus_space_read_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HS);
        DPRINTF("%s: exec op %d, addr 0x%x, cmdlen %d, len %d, "
            "flags 0x%x, status 0x%b\n", DEVNAME(sc), op, addr,
            cmdlen, len, flags, st, VIAPM_SMB_HS_BITS);
        if (st & VIAPM_SMB_HS_BUSY)
                return (1);

        if (cold || sc->sc_poll)
                flags |= I2C_F_POLL;

        if (!I2C_OP_STOP_P(op) || cmdlen > 1 || len > 2)
                return (1);

        /* Setup transfer */
        sc->sc_i2c_xfer.op = op;
        sc->sc_i2c_xfer.buf = buf;
        sc->sc_i2c_xfer.len = len;
        sc->sc_i2c_xfer.flags = flags;
        sc->sc_i2c_xfer.error = 0;

        /* Set slave address and transfer direction */
        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_TXSLVA,
            VIAPM_SMB_TXSLVA_ADDR(addr) |
            (I2C_OP_READ_P(op) ? VIAPM_SMB_TXSLVA_READ : 0));

        b = (void *)cmdbuf;
        if (cmdlen > 0)
                /* Set command byte */
                bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh,
                    VIAPM_SMB_HCMD, b[0]);

        if (I2C_OP_WRITE_P(op)) {
                /* Write data */
                b = buf;
                if (len > 0)
                        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh,
                            VIAPM_SMB_HD0, b[0]);
                if (len > 1)
                        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh,
                            VIAPM_SMB_HD1, b[1]);
        }

        /* Set SMBus command */
        if (len == 0)
                ctl = VIAPM_SMB_HC_CMD_BYTE;
        else if (len == 1)
                ctl = VIAPM_SMB_HC_CMD_BDATA;
        else if (len == 2)
                ctl = VIAPM_SMB_HC_CMD_WDATA;
        else
                panic("%s: unexpected len %zd", __func__, len);

        if ((flags & I2C_F_POLL) == 0)
                ctl |= VIAPM_SMB_HC_INTREN;

        /* Start transaction */
        ctl |= VIAPM_SMB_HC_START;
        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HC, ctl);

        if (flags & I2C_F_POLL) {
                /* Poll for completion */
                DELAY(VIAPM_SMBUS_DELAY);
                for (retries = 1000; retries > 0; retries--) {
                        st = bus_space_read_1(sc->sc_iot, sc->sc_smbus_ioh,
                            VIAPM_SMB_HS);
                        if ((st & VIAPM_SMB_HS_BUSY) == 0)
                                break;
                        DELAY(VIAPM_SMBUS_DELAY);
                }
                if (st & VIAPM_SMB_HS_BUSY)
                        goto timeout;
                viapm_intr(sc);
        } else {
                /* Wait for interrupt */
                if (tsleep_nsec(sc, PRIBIO, "iicexec",
                    SEC_TO_NSEC(VIAPM_SMBUS_TIMEOUT)))
                        goto timeout;
        }

        if (sc->sc_i2c_xfer.error)
                return (1);

        return (0);

timeout:
        /*
         * Transfer timeout. Kill the transaction and clear status bits.
         */
        printf("%s: timeout, status 0x%b\n", DEVNAME(sc), st,
            VIAPM_SMB_HS_BITS);
        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HC,
            VIAPM_SMB_HC_KILL);
        DELAY(VIAPM_SMBUS_DELAY);
        st = bus_space_read_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HS);
        if ((st & VIAPM_SMB_HS_FAILED) == 0)
                printf("%s: transaction abort failed, status 0x%b\n",
                    DEVNAME(sc), st, VIAPM_SMB_HS_BITS);
        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HS, st);
        return (1);
}

int
viapm_intr(void *arg)
{
        struct viapm_softc *sc = arg;
        u_int8_t st;
        u_int8_t *b;
        size_t len;

        /* Read status */
        st = bus_space_read_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HS);
        if ((st & VIAPM_SMB_HS_BUSY) != 0 || (st & (VIAPM_SMB_HS_INTR |
            VIAPM_SMB_HS_DEVERR | VIAPM_SMB_HS_BUSERR |
            VIAPM_SMB_HS_FAILED)) == 0)
                /* Interrupt was not for us */
                return (0);

        DPRINTF("%s: intr st 0x%b\n", DEVNAME(sc), st, VIAPM_SMB_HS_BITS);

        /* Clear status bits */
        bus_space_write_1(sc->sc_iot, sc->sc_smbus_ioh, VIAPM_SMB_HS, st);

        /* Check for errors */
        if (st & (VIAPM_SMB_HS_DEVERR | VIAPM_SMB_HS_BUSERR |
            VIAPM_SMB_HS_FAILED)) {
                sc->sc_i2c_xfer.error = 1;
                goto done;
        }

        if (st & VIAPM_SMB_HS_INTR) {
                if (I2C_OP_WRITE_P(sc->sc_i2c_xfer.op))
                        goto done;

                /* Read data */
                b = sc->sc_i2c_xfer.buf;
                len = sc->sc_i2c_xfer.len;
                if (len > 0)
                        b[0] = bus_space_read_1(sc->sc_iot, sc->sc_smbus_ioh,
                            VIAPM_SMB_HD0);
                if (len > 1)
                        b[1] = bus_space_read_1(sc->sc_iot, sc->sc_smbus_ioh,
                            VIAPM_SMB_HD1);
        }

done:
        if ((sc->sc_i2c_xfer.flags & I2C_F_POLL) == 0)
                wakeup(sc);
        return (1);
}

int
val_to_uK(unsigned int val)
{
        int i = val / 4;
        int j = val % 4;

        KASSERT(i >= 0 && i <= 255);

        if (j == 0 || i == 255)
                return val_to_temp[i] * 10000;

        /* is linear interpolation ok? */
        return (val_to_temp[i] * (4 - j) +
            val_to_temp[i + 1] * j) * 2500 /* really: / 4 * 10000 */ ;
}

int
val_to_rpm(unsigned int val, int div)
{
        if (val == 0)
                return 0;

        return 1350000 / val / div;
}

long
val_to_uV(unsigned int val, int index)
{
        static const long mult[] =
            {1250000, 1250000, 1670000, 2600000, 6300000};

        KASSERT(index >= 0 && index <= 4);

        return (25LL * val + 133) * mult[index] / 2628;
}

void
viapm_refresh_sensor_data(struct viapm_softc *sc)
{
        int i;
        u_int8_t v, v2;

        /* temperature */
        v = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh, VIAPM_HWMON_TIRQ);
        v2 = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh, VIAPM_HWMON_TSENS1);
        DPRINTF("%s: TSENS1 = %d\n", DEVNAME(sc), (v2 << 2) | (v >> 6));
        sc->sc_data[0].value = val_to_uK((v2 << 2) | (v >> 6));

        v = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh, VIAPM_HWMON_TLOW);
        v2 = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh, VIAPM_HWMON_TSENS2);
        DPRINTF("%s: TSENS2 = %d\n", DEVNAME(sc), (v2 << 2) | ((v >> 4) & 0x3));
        sc->sc_data[1].value = val_to_uK((v2 << 2) | ((v >> 4) & 0x3));

        v2 = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh, VIAPM_HWMON_TSENS3);
        DPRINTF("%s: TSENS3 = %d\n", DEVNAME(sc), (v2 << 2) | (v >> 6));
        sc->sc_data[2].value = val_to_uK((v2 << 2) | (v >> 6));

        /* fan */
        for (i = 3; i <= 4; i++) {
                v = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh,
                    VIAPM_HWMON_FAN1 + i - 3);
                DPRINTF("%s: FAN%d = %d / %d\n", DEVNAME(sc), i - 3, v,
                    sc->sc_fan_div[i - 3]);
                sc->sc_data[i].value = val_to_rpm(v, sc->sc_fan_div[i - 3]);
        }

        /* voltage */
        for (i = 5; i <= 9; i++) {
                v = bus_space_read_1(sc->sc_iot, sc->sc_hwmon_ioh,
                    VIAPM_HWMON_VSENS1 + i - 5);
                DPRINTF("%s: V%d = %d\n", DEVNAME(sc), i - 5, v);
                sc->sc_data[i].value = val_to_uV(v, i - 5);
        }
}

void
viapm_refresh(void *arg)
{
        struct viapm_softc *sc = (struct viapm_softc *)arg;

        viapm_refresh_sensor_data(sc);
        timeout_add_msec(&viapm_timeout, 1500);
}

u_int
viapm_get_timecount(struct timecounter *tc)
{
        struct viapm_softc *sc = tc->tc_priv;
        u_int u1, u2, u3;

        u2 = bus_space_read_4(sc->sc_iot, sc->sc_pm_ioh, VIAPM_PM_TMR);
        u3 = bus_space_read_4(sc->sc_iot, sc->sc_pm_ioh, VIAPM_PM_TMR);
        do {
                u1 = u2;
                u2 = u3;
                u3 = bus_space_read_4(sc->sc_iot, sc->sc_pm_ioh, VIAPM_PM_TMR);
        } while (u1 > u2 || u2 > u3);

        return (u2);
}