/*
 * 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.
 */

/*
 * IO Performance Counter Driver
 */

#include <sys/types.h>
#include <sys/ddi.h>
#include <sys/modctl.h>
#include "iospc.h"

/* Debugging level. */
#ifdef DEBUG
int iospc_debug = 0;
#endif /* DEBUG */

/* State structure anchor. */
void *iospc_state_p;

static int iospc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
static int iospc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);
static int iospc_create_name_kstat(iospc_grp_t *grp);
static void iospc_delete_name_kstats(kstat_t **name_kstats_pp,
    int num_kstats);
static kstat_t *iospc_create_cntr_kstat(char *name, int dev_inst,
    int (*update)(kstat_t *, int), iospc_ksinfo_t *ksinfop, int num_pics);
static int iospc_kstat_update(kstat_t *ksp, int rw);
static kstat_t *iospc_create_picN_kstat(char *mod_name, int pic,
    uint64_t mask, int num_ev, iospc_event_t *ev_array);

iospc_grp_t **iospc_leaf_grps = NULL;
int iospc_kstat_inited = 0;
kmutex_t iospc_mutex;

static struct dev_ops iospc_ops = {
        DEVO_REV,
        0,
        nulldev,
        nulldev,
        nulldev,
        iospc_attach,
        iospc_detach,
        nodev,
        NULL,
        NULL,
        nodev
};

extern struct mod_ops mod_driverops;

static struct modldrv md = {
        &mod_driverops,
        "IO Perf Counter Driver",
        &iospc_ops,
};

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

/*
 * One-time module-wide initialization.
 */
int
_init(void)
{
        int rval;

        /* Initialize per-leaf soft state pointer. */
        if ((rval = ddi_soft_state_init(&iospc_state_p,
            sizeof (iospc_t), 1)) != DDI_SUCCESS)
                return (rval);

        /* If all checks out, install the module. */
        if ((rval = mod_install(&ml)) != DDI_SUCCESS) {
                ddi_soft_state_fini(&iospc_state_p);
                return (rval);
        }
        mutex_init(&iospc_mutex, NULL, MUTEX_DRIVER, NULL);
        return (DDI_SUCCESS);
}

/*
 * One-time module-wide cleanup, after last detach is done.
 */
int
_fini(void)
{
        int rval;

        /*
         * Remove the module first as this operation is the only thing here
         * which can fail.
         */
        rval = mod_remove(&ml);
        if (rval != DDI_SUCCESS)
                return (rval);

        if (iospc_leaf_grps != NULL) {
                iospc_kstat_fini();
                mutex_enter(&iospc_mutex);
                iospc_kstat_inited = 0;
                (void) rfios_unbind_group();
                iospc_leaf_grps = NULL;
                mutex_exit(&iospc_mutex);
        }

        mutex_destroy(&iospc_mutex);

        /* Free px soft state */
        ddi_soft_state_fini(&iospc_state_p);

        return (DDI_SUCCESS);
}

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

/*
 * Per-instance initialization.  Suspend/resume not supported.
 */
static int
iospc_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
        iospc_t *iospc_p;
        int instance = ddi_get_instance(dip);
        char *ptr;

        IOSPC_DBG2("iospc: iospc_attach: enter\n");
        switch (cmd) {
        case DDI_RESUME:
        case DDI_ATTACH:
                /* Initialize one-time kstat structures. */
                mutex_enter(&iospc_mutex);
                if (!iospc_kstat_inited) {
                        if ((ddi_prop_lookup_string(DDI_DEV_T_ANY, dip,
                            0, "compatible", &ptr)) != DDI_PROP_SUCCESS)
                                goto bad_property;

                        if ((strcmp(ptr, "SUNW,ktios-pr") == 0) ||
                            (strcmp(ptr, "SUNW,rfios-pr") == 0)) {
                                iospc_leaf_grps = rfios_bind_group();
                        } else {
                                ddi_prop_free(ptr);
                                goto bad_property;
                        }

                        ddi_prop_free(ptr);

                        if (iospc_kstat_init() != DDI_SUCCESS)
                                goto bad_kstat_init;

                        iospc_kstat_inited++;
                }
                mutex_exit(&iospc_mutex);

                if (ddi_soft_state_zalloc(iospc_state_p, instance) !=
                    DDI_SUCCESS) {
                        goto bad_softstate;
                }

                iospc_p = (iospc_t *)ddi_get_soft_state(iospc_state_p,
                    instance);

                iospc_p->iospc_dip = dip;

                /* Set up kstats. */

                if (iospc_kstat_attach(iospc_p) != DDI_SUCCESS)
                        goto bad_kstat_attach;

                IOSPC_DBG2("iospc: iospc_attach: exit SUCCESS\n");

                return (DDI_SUCCESS);

bad_kstat_attach:
                (void) ddi_soft_state_free(iospc_state_p, instance);
bad_softstate:
                iospc_kstat_fini();
bad_kstat_init:
bad_property:
                mutex_enter(&iospc_mutex);
                IOSPC_DBG2("iospc: iospc_attach: exit FAILURE\n");
                return (DDI_FAILURE);

        default:
                return (DDI_FAILURE);
        }
}

/*
 * Per-instance cleanup.  Suspend/resume not supported.
 */
static int
iospc_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
        int instance = ddi_get_instance(dip);

        IOSPC_DBG2("iospc: iospc_detach: enter\n");
        iospc_t *iospc_p = (iospc_t *)ddi_get_soft_state(
            iospc_state_p, instance);

        switch (cmd) {
        case DDI_SUSPEND:
        case DDI_DETACH:
                iospc_kstat_detach(iospc_p);
                (void) ddi_soft_state_free(iospc_state_p, instance);

                IOSPC_DBG2("iospc: iospc_detach: exit - SUCCESS\n");
                return (DDI_SUCCESS);

        default:
                IOSPC_DBG2("iospc: iospc_detach: exit - FAILURE\n");
                return (DDI_FAILURE);
        }
}

#define PIC_STR_LEN     5       /* Size of a PICx name string. */

/*
 * One-time initialization for this module.
 */
int
iospc_kstat_init()
{
        iospc_grp_t **grp_pp;
        iospc_grp_t *grp_p;

        IOSPC_DBG2("iospc: kstat_init: enter\n");

        /*
         * Initialize the name kstats for each group, drawing upon the table
         * for values.
         */
        for (grp_pp = iospc_leaf_grps; *grp_pp != NULL; grp_pp++) {

                grp_p = *grp_pp;

                IOSPC_DBG2("Setting up group for %s\n", grp_p->grp_name);

                /* Create basic pic event-type pair. */
                grp_p->name_kstats_pp = kmem_zalloc((grp_p->num_counters *
                    sizeof (kstat_t)), KM_SLEEP);
                if (iospc_create_name_kstat(grp_p) != DDI_SUCCESS) {
                        iospc_kstat_fini();
                        IOSPC_DBG1("iospc: init: failure exit\n");
                        return (DDI_FAILURE);
                }
        }

        IOSPC_DBG2("iospc: kstat_init: success exit\n");

        return (DDI_SUCCESS);
}

/*
 * Per-instance initialization for this module.
 */
int
iospc_kstat_attach(iospc_t *iospc_p)
{
        iospc_grp_t **grp_pp;
        iospc_grp_t *grp_p;
        iospc_ksinfo_t *ksinfo_p;

        int i;

        IOSPC_DBG2("iospc: kstat_attach %d: enter\n",
            ddi_get_instance(iospc_p->iospc_dip));

        /* Set up kstats for each group. */
        for (i = 0, grp_pp = iospc_leaf_grps; *grp_pp != NULL; i++, grp_pp++) {

                if (i >= IOSPC_MAX_NUM_GRPS)
                        goto err;

                grp_p = *grp_pp;

                /*
                 * ksinfo_p keeps all info needed by iospc_kstat_update,
                 * which is fired off asynchronously on demand by the kstat
                 * framework.
                 */
                ksinfo_p = (iospc_ksinfo_t *)kmem_zalloc(
                    sizeof (iospc_ksinfo_t), KM_SLEEP);

                ksinfo_p->iospc_p = iospc_p;
                ksinfo_p->grp_p  = grp_p;

                /* Also save in state structure, for later cleanup. */
                iospc_p->iospc_ksinfo_p[i] = ksinfo_p;

                /* Create counter kstats */
                ksinfo_p->cntr_ksp = iospc_create_cntr_kstat(grp_p->grp_name,
                    ddi_get_instance(iospc_p->iospc_dip),
                    iospc_kstat_update, ksinfo_p, grp_p->num_counters);

                if (ksinfo_p->cntr_ksp == NULL)
                        goto err;

                if (grp_p->access_init(iospc_p, ksinfo_p) != SUCCESS)
                        goto err;
        }

        IOSPC_DBG2("iospc: kstat_attach: success exit\n");
        return (DDI_SUCCESS);
err:
        iospc_kstat_detach(iospc_p);
        IOSPC_DBG2("iospc: kstat_attach: failure exit\n");
        return (DDI_FAILURE);
}

/*
 * Create the name kstats for each group.
 */
static int
iospc_create_name_kstat(iospc_grp_t *grp_p)
{
        int i;

        for (i = 0; i < grp_p->num_counters; i++) {
                grp_p->name_kstats_pp[i] = iospc_create_picN_kstat(
                    grp_p->grp_name, i,
                    grp_p->regsel_p->fields_p[i].event_offset,
                    grp_p->regsel_p->fields_p[i].num_events,
                    grp_p->regsel_p->fields_p[i].events_p);

                if (grp_p->name_kstats_pp[i] == NULL)
                        return (DDI_FAILURE);
        }
        return (DDI_SUCCESS);
}

/*
 * Create the picN kstat. Returns a pointer to the
 * kstat which the driver must store to allow it
 * to be deleted when necessary.
 */
static kstat_t *
iospc_create_picN_kstat(char *mod_name, int pic, uint64_t ev_offset,
    int num_ev, iospc_event_t *ev_array)
{
        int event;
        char pic_name[PIC_STR_LEN];
        kstat_t *picN_ksp = NULL;
        struct kstat_named *pic_named_data;

        (void) snprintf(pic_name, PIC_STR_LEN, "pic%1d", pic);

        if ((picN_ksp = kstat_create(mod_name, 0, pic_name,
            "bus", KSTAT_TYPE_NAMED, num_ev, 0)) == NULL) {
                return (NULL);
        }

        /* NOTE: Number of events is assumed to always be non-zero. */

        pic_named_data = (struct kstat_named *)picN_ksp->ks_data;

        /*
         * Fill up data section of the kstat
         * Write event names and their associated pcr masks.
         * num_ev - 1 is because CLEAR_PIC is added separately.
         */
        for (event = 0; event < num_ev - 1; event++) {
                pic_named_data[event].value.ui64 =
                    ev_array[event].value << ev_offset;

                kstat_named_init(&pic_named_data[event],
                    ev_array[event].name, KSTAT_DATA_UINT64);
        }

        /*
         * add the clear_pic entry
         */
        pic_named_data[event].value.ui64 =
            (uint64_t)~(ev_array[event].value << ev_offset);

        kstat_named_init(&pic_named_data[event], ev_array[event].name,
            KSTAT_DATA_UINT64);

        kstat_install(picN_ksp);

        return (picN_ksp);
}

/*
 * Create the "counters" kstat.
 */
static kstat_t *
iospc_create_cntr_kstat(char *name, int dev_inst,
    int (*update)(kstat_t *, int), iospc_ksinfo_t *ksinfop, int num_pics)
{
        int i;
        char pic_str[PIC_STR_LEN];
        struct kstat *counters_ksp;
        struct kstat_named *counters_named_data;

        IOSPC_DBG2("iospc_create_cntr_kstat: name: %s instance: %d\n",
            name, dev_inst);

        /*
         * Size of kstat is num_pics + 1. extra one for pcr.
         */

        if ((counters_ksp = kstat_create(name, dev_inst, "counters", "bus",
            KSTAT_TYPE_NAMED, num_pics + 1, KSTAT_FLAG_WRITABLE)) == NULL) {
                return (NULL);
        }

        counters_named_data = (struct kstat_named *)(counters_ksp->ks_data);
        kstat_named_init(&counters_named_data[0], "pcr", KSTAT_DATA_UINT64);

        for (i = 0; i < num_pics; i++) {
                (void) snprintf(pic_str, PIC_STR_LEN, "pic%1d", i);

                kstat_named_init(&counters_named_data[i+1], pic_str,
                    KSTAT_DATA_UINT64);
        }

        /*
         * Store the reg type and other info. in the kstat's private field
         * so that they are available to the update function.
         */
        counters_ksp->ks_private = (void *)ksinfop;
        counters_ksp->ks_update = update;

        kstat_install(counters_ksp);

        return (counters_ksp);
}

/*
 * Program a performance counter.
 *
 * reggroup is which type of counter.
 * counter is the counter number.
 * event is the event to program for that counter.
 */
static int
iospc_perfcnt_program(iospc_t *iospc_p, iospc_grp_t *grp_p,
    iospc_ksinfo_t *ksinfo_p, uint64_t new_events)
{
        uint64_t old_events;
        int rval = SUCCESS;
        uint64_t event_mask;
        int counter;

        IOSPC_DBG1(
            "iospc_perfcnt_program enter: new_events:0x%" PRIx64 "\n",
            new_events);

        if ((rval = grp_p->access(iospc_p, ksinfo_p->arg, IOSPC_REG_READ,
            grp_p->regsel_p->regoff, &old_events)) != SUCCESS)
                goto done_pgm;

        IOSPC_DBG1("  old_events:0x%" PRIx64 "\n", old_events);

        for (counter = 0; counter < grp_p->num_counters; counter++) {

                if (grp_p->counters_p[counter].zero_regoff == NO_REGISTER)
                        continue;

                event_mask = grp_p->regsel_p->fields_p[counter].event_mask <<
                    grp_p->regsel_p->fields_p[counter].event_offset;

                IOSPC_DBG1(
                    "grp:%s, counter:%d, zero_regoff:0x%lx, "
                    "event_mask:0x%" PRIx64 ", old&mask:0x%lx, "
                    "new&mask:0x%lx\n",
                    grp_p->grp_name, counter,
                    grp_p->counters_p[counter].zero_regoff,
                    event_mask, old_events & event_mask,
                    new_events & event_mask);

                if ((old_events & event_mask) ==
                    (new_events & event_mask))
                        continue;

                IOSPC_DBG1("Zeroing counter %d\n", counter);

                if ((rval = grp_p->access(iospc_p, ksinfo_p->arg,
                    IOSPC_REG_WRITE, grp_p->counters_p[counter].zero_regoff,
                    &grp_p->counters_p[counter].zero_value)) != SUCCESS)
                        goto done_pgm;
        }

        if (old_events != new_events) {

                IOSPC_DBG1("old != new, setting event reg %ld to 0x%lx\n",
                    grp_p->regsel_p->regoff, new_events);

                if ((rval = grp_p->access(iospc_p, ksinfo_p->arg,
                    IOSPC_REG_WRITE, grp_p->regsel_p->regoff, &new_events))
                    != SUCCESS) {
                        IOSPC_DBG1(
                            "Write of new event data failed, "
                            "select reg offset: %ld\n",
                            grp_p->regsel_p->regoff);
                        goto done_pgm;
                }
        }
done_pgm:
        IOSPC_DBG1("iospc_perfcnt_program: returning status %d.\n", rval);
        return (rval);
}

/*
 * kstat update function. Handles reads/writes
 * from/to kstat.
 */
static int
iospc_kstat_update(kstat_t *ksp, int rw)
{
        struct kstat_named *data_p;
        int counter;
        iospc_ksinfo_t *ksinfop = ksp->ks_private;
        iospc_grp_t *grp_p = ksinfop->grp_p;
        iospc_t *iospc_p = ksinfop->iospc_p;

        data_p = (struct kstat_named *)ksp->ks_data;

        if (rw == KSTAT_WRITE) {

                IOSPC_DBG2("iospc_kstat_update: wr %ld\n",
                    data_p[0].value.ui64);

                /*
                 * Fields without programmable events won't be zeroed as
                 * iospc_perfcnt_program is what zeros them.
                 */

                /* This group has programmable events. */
                if (grp_p->regsel_p->regoff != NO_REGISTER) {

                        IOSPC_DBG2("write: regoff has valid register\n");
                        if (iospc_perfcnt_program(iospc_p, grp_p, ksinfop,
                            data_p[0].value.ui64) != SUCCESS)
                                return (EIO);
                }

        } else {        /* Read the event register and all of the counters. */

                /* This group has programmable events. */
                if (grp_p->regsel_p->regoff != NO_REGISTER) {

                        IOSPC_DBG2("read: regoff has valid register\n");

                        if (grp_p->access(iospc_p, ksinfop->arg, IOSPC_REG_READ,
                            grp_p->regsel_p->regoff, &data_p[0].value.ui64)
                            != SUCCESS)
                                return (EIO);
                } else
                        data_p[0].value.ui64 = 0ull;

                IOSPC_DBG2("iospc_kstat_update: rd event %lx\n",
                    data_p[0].value.ui64);

                for (counter = 0; counter < grp_p->num_counters; counter++) {

                        if (grp_p->access(iospc_p, ksinfop->arg, IOSPC_REG_READ,
                            grp_p->counters_p[counter].regoff,
                            &data_p[counter + 1].value.ui64) != SUCCESS)
                                return (EIO);

                        IOSPC_DBG2("cntr%d, off:0x%lx, val:0x%lx\n", counter,
                            grp_p->counters_p[counter].regoff,
                            data_p[counter + 1].value.ui64);
                }
        }
        return (SUCCESS);
}

void
iospc_kstat_fini()
{
        iospc_grp_t **grp_pp;
        iospc_grp_t *grp_p;
        int j;

        IOSPC_DBG2("iospc_kstat_fini called\n");

        for (j = 0, grp_pp = iospc_leaf_grps; *grp_pp != NULL; j++, grp_pp++) {
                grp_p = *grp_pp;
                if (grp_p->name_kstats_pp != NULL) {
                        iospc_delete_name_kstats(grp_p->name_kstats_pp,
                            grp_p->num_counters);
                        kmem_free(grp_p->name_kstats_pp,
                            grp_p->num_counters * sizeof (kstat_t));
                        grp_p->name_kstats_pp = NULL;
                }
        }
}

static void
iospc_delete_name_kstats(kstat_t **name_kstats_pp, int num_kstats)
{
        int i;

        if (name_kstats_pp != NULL) {
                for (i = 0; i < num_kstats; i++) {
                        if (name_kstats_pp[i] != NULL)
                                kstat_delete(name_kstats_pp[i]);
                }
        }
}

void
iospc_kstat_detach(iospc_t *iospc_p)
{
        iospc_grp_t **grp_pp;
        iospc_grp_t *grp_p;
        int i;

        IOSPC_DBG2("iospc_kstat_detach called\n");

        for (i = 0, grp_pp = iospc_leaf_grps; *grp_pp != NULL; i++, grp_pp++) {

                if (i >= IOSPC_MAX_NUM_GRPS)
                        return;

                grp_p = *grp_pp;
                if (iospc_p->iospc_ksinfo_p[i] != NULL) {

                        grp_p->access_fini(iospc_p, iospc_p->iospc_ksinfo_p[i]);

                        if (iospc_p->iospc_ksinfo_p[i]->cntr_ksp != NULL)
                                kstat_delete(
                                    iospc_p->iospc_ksinfo_p[i]->cntr_ksp);
                        kmem_free(iospc_p->iospc_ksinfo_p[i],
                            sizeof (iospc_ksinfo_t));
                }

        }
}