sun4u/io/pmugpio.c

	pmugpio.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * 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 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

#include <sys/types.h>
#include <sys/conf.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/modctl.h>
#include <sys/ddi_impldefs.h>
#include <sys/kmem.h>
#include <sys/devops.h>

/*
 * Time periods, in nanoseconds
 */
#define PMUGPIO_TWO_SEC     2000000000LL

static  dev_info_t  *pmugpio_dip;

typedef struct pmugpio_state {
    uint8_t         *pmugpio_reset_reg;
    ddi_acc_handle_t    pmugpio_reset_reg_handle;
    uint8_t         *pmugpio_watchdog_reg;
    ddi_acc_handle_t    pmugpio_watchdog_reg_handle;
    hrtime_t        hw_last_pat;
} pmugpio_state_t;

static void *pmugpio_statep;

static int pmugpio_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
static int pmugpio_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);
static int pmugpio_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
        void **result);
static int pmugpio_map_regs(dev_info_t *, pmugpio_state_t *);

struct cb_ops pmugpio_cb_ops = {
    nulldev,    /* open  */
    nulldev,    /* close */
    nulldev,    /* strategy */
    nulldev,    /* print */
    nulldev,    /* dump */
    nulldev,    /* read */
    nulldev,    /* write */
    nulldev,    /* ioctl */
    nulldev,    /* devmap */
    nulldev,    /* mmap */
    nulldev,    /* segmap */
    nochpoll,   /* poll */
    ddi_prop_op,    /* cb_prop_op */
    NULL,       /* streamtab  */
    D_MP | D_NEW
};

static struct dev_ops pmugpio_ops = {
    DEVO_REV,       /* Devo_rev */
    0,          /* Refcnt */
    pmugpio_info,       /* Info */
    nulldev,        /* Identify */
    nulldev,        /* Probe */
    pmugpio_attach,     /* Attach */
    pmugpio_detach,     /* Detach */
    nodev,          /* Reset */
    &pmugpio_cb_ops,        /* Driver operations */
    0,          /* Bus operations */
    NULL            /* Power */
};

static struct modldrv modldrv = {
    &mod_driverops,         /* This one is a driver */
    "Pmugpio Driver %I%",       /* Name of the module. */
    &pmugpio_ops,           /* Driver ops */
};

static struct modlinkage modlinkage = {
    MODREV_1, (void *)&modldrv, NULL
};

int
_init(void)
{
    int error;

    /* Initialize the soft state structures */
    if ((error = ddi_soft_state_init(&pmugpio_statep,
        sizeof (pmugpio_state_t), 1)) != 0) {
        return (error);
    }

    /* Install the loadable module */
    if ((error = mod_install(&modlinkage)) != 0) {
        ddi_soft_state_fini(&pmugpio_statep);
    }
    return (error);
}

int
_info(struct modinfo *modinfop)
{
    return (mod_info(&modlinkage, modinfop));
}

int
_fini(void)
{
    int error;

    error = mod_remove(&modlinkage);
    if (error == 0) {
        /* Release per module resources */
        ddi_soft_state_fini(&pmugpio_statep);
    }
    return (error);
}

static int
pmugpio_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
    int     instance;
    pmugpio_state_t *pmugpio_ptr = NULL;

    switch (cmd) {
    case DDI_ATTACH:
        break;
    case DDI_RESUME:
        return (DDI_SUCCESS);
    default:
        return (DDI_FAILURE);
    }

    /* Get the instance and create soft state */
    instance = ddi_get_instance(dip);
    if (ddi_soft_state_zalloc(pmugpio_statep, instance) != 0) {
        return (DDI_FAILURE);
    }
    pmugpio_ptr = ddi_get_soft_state(pmugpio_statep, instance);
    if (pmugpio_ptr == NULL) {
        return (DDI_FAILURE);
    }

    if (pmugpio_map_regs(dip, pmugpio_ptr) != DDI_SUCCESS) {
        ddi_soft_state_free(pmugpio_statep, instance);
        return (DDI_FAILURE);
    }

    /* Display information in the banner */
    ddi_report_dev(dip);

    /* Save the dip */
    pmugpio_dip = dip;

    return (DDI_SUCCESS);
}

/* ARGSUSED */
static int
pmugpio_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
    /* Pointer to soft state */
    switch (cmd) {
    case DDI_SUSPEND:
        return (DDI_SUCCESS);
    default:
        return (DDI_FAILURE);
    }
}

/* ARGSUSED */
static int
pmugpio_info(dev_info_t *dip, ddi_info_cmd_t infocmd,
        void *arg, void **result)
{
    dev_t dev;
    int instance, error;

    switch (infocmd) {
    case DDI_INFO_DEVT2DEVINFO:
        *result = (void *)pmugpio_dip;
        error = DDI_SUCCESS;
        break;
    case DDI_INFO_DEVT2INSTANCE:
        dev = (dev_t)arg;
        instance = getminor(dev);
        *result = (void *)(uintptr_t)instance;
        error = DDI_SUCCESS;
        break;
    default:
        error = DDI_FAILURE;
    }
    return (error);
}

void
pmugpio_watchdog_pat(void)
{
    dev_info_t *dip = pmugpio_dip;
    int instance;
    pmugpio_state_t *pmugpio_ptr;
    hrtime_t now;
    uint8_t value;

    if (dip == NULL) {
        return;
    }
    instance = ddi_get_instance(dip);
    pmugpio_ptr = ddi_get_soft_state(pmugpio_statep, instance);
    if (pmugpio_ptr == NULL) {
        return;
    }
    /*
     * The RMC can read interrupts either high to low OR low to high. As
     * a result all that needs to happen is that when we hit the time to
     * send an signal we simply need to change the state.
     */
    now = gethrtime();
    if ((now - pmugpio_ptr->hw_last_pat) >= PMUGPIO_TWO_SEC) {
        /*
         * fetch current reg value and invert it
         */
        value = (uint8_t)(0xff ^
            ddi_get8(pmugpio_ptr->pmugpio_watchdog_reg_handle,
            pmugpio_ptr->pmugpio_watchdog_reg));

        ddi_put8(pmugpio_ptr->pmugpio_watchdog_reg_handle,
            pmugpio_ptr->pmugpio_watchdog_reg, value);
        pmugpio_ptr->hw_last_pat = now;
    }
}

void
pmugpio_reset(void)
{
    dev_info_t *dip = pmugpio_dip;
    int instance;
    pmugpio_state_t *pmugpio_ptr;

    if (dip == NULL) {
        return;
    }
    instance = ddi_get_instance(dip);
    pmugpio_ptr = ddi_get_soft_state(pmugpio_statep, instance);
    if (pmugpio_ptr == NULL) {
        return;
    }

    /*
     * turn all bits on then off again - pmubus nexus will ensure
     * that only unmasked bit is affected
     */
    ddi_put8(pmugpio_ptr->pmugpio_reset_reg_handle,
        pmugpio_ptr->pmugpio_reset_reg, ~0);
    ddi_put8(pmugpio_ptr->pmugpio_reset_reg_handle,
        pmugpio_ptr->pmugpio_reset_reg, 0);
}

static int
pmugpio_map_regs(dev_info_t *dip, pmugpio_state_t *pmugpio_ptr)
{
    ddi_device_acc_attr_t attr;

    /* The host controller will be little endian */
    attr.devacc_attr_version = DDI_DEVICE_ATTR_V0;
    attr.devacc_attr_endian_flags  = DDI_STRUCTURE_LE_ACC;
    attr.devacc_attr_dataorder = DDI_STRICTORDER_ACC;

    if (ddi_regs_map_setup(dip, 1,
        (caddr_t *)&pmugpio_ptr->pmugpio_watchdog_reg, 0, 1, &attr,
        &pmugpio_ptr->pmugpio_watchdog_reg_handle) != DDI_SUCCESS) {
        return (DDI_FAILURE);
    }
    if (ddi_regs_map_setup(dip, 0,
        (caddr_t *)&pmugpio_ptr->pmugpio_reset_reg, 0, 1, &attr,
        &pmugpio_ptr->pmugpio_reset_reg_handle) != DDI_SUCCESS) {
        ddi_regs_map_free(&pmugpio_ptr->pmugpio_watchdog_reg_handle);
        return (DDI_FAILURE);
    }
    return (DDI_SUCCESS);
}