/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright (c) 2011 Bayard G. Bell. All rights reserved.
 */


#include <sys/types.h>
#include <sys/conf.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/ddi_impldefs.h>
#include <sys/obpdefs.h>
#include <sys/cmn_err.h>
#include <sys/errno.h>
#include <sys/kmem.h>
#include <sys/debug.h>
#include <sys/sysmacros.h>
#include <sys/ivintr.h>
#include <sys/intr.h>
#include <sys/intreg.h>
#include <sys/autoconf.h>
#include <sys/modctl.h>
#include <sys/spl.h>

#include <sys/fhc.h>
#include <sys/simmstat.h>

/* Useful debugging Stuff */
#include <sys/nexusdebug.h>

/*
 * Function prototypes
 */

static int simmstat_attach(dev_info_t *, ddi_attach_cmd_t);

static int simmstat_detach(dev_info_t *, ddi_detach_cmd_t);

static void simmstat_add_kstats(struct simmstat_soft_state *);

static int simmstat_kstat_update(kstat_t *, int);

/*
 * Configuration data structures
 */
static struct cb_ops simmstat_cb_ops = {
        nulldev,                        /* open */
        nulldev,                        /* close */
        nulldev,                        /* strategy */
        nulldev,                        /* print */
        nodev,                          /* dump */
        nulldev,                        /* read */
        nulldev,                        /* write */
        nulldev,                        /* ioctl */
        nodev,                          /* devmap */
        nodev,                          /* mmap */
        nodev,                          /* segmap */
        nochpoll,                       /* poll */
        ddi_prop_op,                    /* cb_prop_op */
        0,                              /* streamtab */
        D_MP | D_NEW | D_HOTPLUG,       /* Driver compatibility flag */
        CB_REV,                         /* rev */
        nodev,                          /* cb_aread */
        nodev                           /* cb_awrite */
};

static struct dev_ops simmstat_ops = {
        DEVO_REV,                       /* rev */
        0,                              /* refcnt  */
        ddi_no_info,                    /* getinfo */
        nulldev,                        /* identify */
        nulldev,                        /* probe */
        simmstat_attach,                /* attach */
        simmstat_detach,                /* detach */
        nulldev,                        /* reset */
        &simmstat_cb_ops,               /* cb_ops */
        (struct bus_ops *)0,            /* bus_ops */
        nulldev,                        /* power */
        ddi_quiesce_not_needed,                 /* quiesce */
};

static uint_t simmstat_reg_read_delay_us = 10;

/*
 * Driver globals
 */
void *simmstatp;

extern struct mod_ops mod_driverops;

static struct modldrv modldrv = {
        &mod_driverops,                 /* module type, this one is a driver */
        "SIMM-status Leaf",             /* module name */
        &simmstat_ops,                  /* driver ops */
};

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

/*
 * These are the module initialization routines.
 */

int
_init(void)
{
        int error;

        if ((error = ddi_soft_state_init(&simmstatp,
            sizeof (struct simmstat_soft_state), 1)) != 0)
                return (error);

        return (mod_install(&modlinkage));
}

int
_fini(void)
{
        int error;

        if ((error = mod_remove(&modlinkage)) != 0)
                return (error);

        ddi_soft_state_fini(&simmstatp);
        return (0);
}

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

static int
simmstat_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
{
        struct simmstat_soft_state *softsp;
        int instance;

        switch (cmd) {
        case DDI_ATTACH:
                break;

        case DDI_RESUME:
                return (DDI_SUCCESS);

        default:
                return (DDI_FAILURE);
        }

        instance = ddi_get_instance(devi);

        if (ddi_soft_state_zalloc(simmstatp, instance) != DDI_SUCCESS)
                return (DDI_FAILURE);

        softsp = ddi_get_soft_state(simmstatp, instance);

        /* Set the dip in the soft state */
        softsp->dip = devi;

        /* Get the board number from this nodes parent device. */
        softsp->pdip = ddi_get_parent(softsp->dip);
        if ((softsp->board = (int)ddi_getprop(DDI_DEV_T_ANY, softsp->pdip,
            DDI_PROP_DONTPASS, OBP_BOARDNUM, -1)) == -1) {
                cmn_err(CE_WARN, "simmstat%d: unable to retrieve %s property",
                    instance, OBP_BOARDNUM);
                goto bad;
        }

        DPRINTF(SIMMSTAT_ATTACH_DEBUG, ("simmstat%d: devi= 0x%p\n, "
            " softsp=0x%p\n", instance, (void *)devi, (void *)softsp));

        /* map in the registers for this device. */
        if (ddi_map_regs(softsp->dip, 0,
            (caddr_t *)&softsp->simmstat_base, 0, 0)) {
                cmn_err(CE_WARN, "simmstat%d: unable to map registers",
                    instance);
                goto bad;
        }

        /* nothing to suspend/resume here */
        (void) ddi_prop_update_string(DDI_DEV_T_NONE, devi,
            "pm-hardware-state", "no-suspend-resume");

        /* create the kstats for this device */
        simmstat_add_kstats(softsp);

        ddi_report_dev(devi);

        return (DDI_SUCCESS);

bad:
        ddi_soft_state_free(simmstatp, instance);
        return (DDI_FAILURE);
}

/* ARGSUSED */
static int
simmstat_detach(dev_info_t *devi, ddi_detach_cmd_t cmd)
{
        int instance;
        struct simmstat_soft_state *softsp;

        /* get the instance of this devi */
        instance = ddi_get_instance(devi);

        /* get the soft state pointer for this device node */
        softsp = ddi_get_soft_state(simmstatp, instance);

        switch (cmd) {
        case DDI_SUSPEND:
                return (DDI_SUCCESS);

        case DDI_DETACH:
                (void) fhc_bdlist_lock(softsp->board);
                if (fhc_bd_detachable(softsp->board))
                        break;
                else
                        fhc_bdlist_unlock();
                /* FALLTHROUGH */

        default:
                return (DDI_FAILURE);
        }

        fhc_bdlist_unlock();

        /* remove the kstat for this board */
        kstat_delete(softsp->simmstat_ksp);

        /* unmap the registers */
        ddi_unmap_regs(softsp->dip, 0,
            (caddr_t *)&softsp->simmstat_base, 0, 0);

        /* free up the soft state */
        ddi_soft_state_free(simmstatp, instance);
        ddi_prop_remove_all(devi);

        return (DDI_SUCCESS);
}

static void
simmstat_add_kstats(struct simmstat_soft_state *softsp)
{
        struct kstat *simmstat_ksp;

        if ((simmstat_ksp = kstat_create("unix", softsp->board,
            SIMMSTAT_KSTAT_NAME, "misc", KSTAT_TYPE_RAW,
            SIMM_COUNT, KSTAT_FLAG_PERSISTENT)) == NULL) {
                cmn_err(CE_WARN, "simmstat%d: kstat_create failed",
                    ddi_get_instance(softsp->dip));
        }

        simmstat_ksp->ks_update = simmstat_kstat_update;
        simmstat_ksp->ks_private = (void *)softsp;
        softsp->simmstat_ksp = simmstat_ksp;
        kstat_install(simmstat_ksp);
}

/*
 * Kstats only need ks_update functions when they change dynamically
 * at run time.
 * In the case of the simmstat registers, they contain battery
 * information for NVSIMMs. These need to be updated whenever a
 * kstat_read asks for the data. There is currently no plan to
 * ship NVSIMMs on this platform, but this support must be present.
 */

static int
simmstat_kstat_update(kstat_t *ksp, int rw)
{
        struct simmstat_soft_state *softsp;
        volatile char *statp;   /* pointer to hardware register */
        char *kstatp;           /* pointer to kstat data buffer */
        int i;

        kstatp = (char *)ksp->ks_data;
        softsp = (struct simmstat_soft_state *)ksp->ks_private;

        statp = (char *)softsp->simmstat_base;

        /* this is a read-only kstat. Bail out on a write */
        if (rw == KSTAT_WRITE) {
                return (EACCES);
        } else {

                /*
                 * copy current status of hardware into the kstat
                 * structure.
                 */
                for (i = 0; i < SIMM_COUNT; i++, statp++, kstatp++) {
                        *kstatp = *statp;
                        DELAY(simmstat_reg_read_delay_us);
                }
        }
        return (0);
}