/*-
 * Copyright (c) 2016-2017 Alexander Motin <mav@FreeBSD.org>
 * 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.
 *
 * 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 AUTHOR 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.
 */

#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/rmlock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/sbuf.h>
#include <sys/sysctl.h>

#include "ntb.h"

SYSCTL_NODE(_hw, OID_AUTO, ntb, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
    "NTB sysctls");

struct ntb_child {
        device_t        dev;
        int             function;
        int             enabled;
        int             mwoff;
        int             mwcnt;
        int             spadoff;
        int             spadcnt;
        int             dboff;
        int             dbcnt;
        uint64_t        dbmask;
        void            *ctx;
        const struct ntb_ctx_ops *ctx_ops;
        struct rmlock   ctx_lock;
        struct ntb_child *next;
};

int
ntb_register_device(device_t dev)
{
        struct ntb_child **cpp = device_get_softc(dev);
        struct ntb_child *nc;
        int i, mw, mwu, mwt, spad, spadu, spadt, db, dbu, dbt;
        char cfg[128] = "";
        char buf[32];
        char *n, *np, *c, *p, *name;

        mwu = 0;
        mwt = NTB_MW_COUNT(dev);
        spadu = 0;
        spadt = NTB_SPAD_COUNT(dev);
        dbu = 0;
        dbt = flsll(NTB_DB_VALID_MASK(dev));

        device_printf(dev, "%d memory windows, %d scratchpads, "
            "%d doorbells\n", mwt, spadt, dbt);

        snprintf(buf, sizeof(buf), "hint.%s.%d.config", device_get_name(dev),
            device_get_unit(dev));
        TUNABLE_STR_FETCH(buf, cfg, sizeof(cfg));
        n = cfg;
        i = 0;
        while ((c = strsep(&n, ",")) != NULL) {
                np = c;
                name = strsep(&np, ":");
                if (name != NULL && name[0] == 0)
                        name = NULL;
                p = strsep(&np, ":");
                mw = (p && p[0] != 0) ? strtol(p, NULL, 10) : mwt - mwu;
                p = strsep(&np, ":");
                spad = (p && p[0] != 0) ? strtol(p, NULL, 10) : spadt - spadu;
                db = (np && np[0] != 0) ? strtol(np, NULL, 10) : dbt - dbu;

                if (mw > mwt - mwu || spad > spadt - spadu || db > dbt - dbu) {
                        device_printf(dev, "Not enough resources for config\n");
                        break;
                }

                nc = malloc(sizeof(*nc), M_DEVBUF, M_WAITOK | M_ZERO);
                nc->function = i;
                nc->mwoff = mwu;
                nc->mwcnt = mw;
                nc->spadoff = spadu;
                nc->spadcnt = spad;
                nc->dboff = dbu;
                nc->dbcnt = db;
                nc->dbmask = (db == 0) ? 0 : (0xffffffffffffffff >> (64 - db));
                rm_init(&nc->ctx_lock, "ntb ctx");
                nc->dev = device_add_child(dev, name, DEVICE_UNIT_ANY);
                if (nc->dev == NULL) {
                        ntb_unregister_device(dev);
                        return (ENOMEM);
                }
                device_set_ivars(nc->dev, nc);
                *cpp = nc;
                cpp = &nc->next;

                if (bootverbose) {
                        device_printf(dev, "%d \"%s\":", i, name);
                        if (mw > 0) {
                                printf(" memory windows %d", mwu);
                                if (mw > 1)
                                        printf("-%d", mwu + mw - 1);
                        }
                        if (spad > 0) {
                                printf(" scratchpads %d", spadu);
                                if (spad > 1)
                                        printf("-%d", spadu + spad - 1);
                        }
                        if (db > 0) {
                                printf(" doorbells %d", dbu);
                                if (db > 1)
                                        printf("-%d", dbu + db - 1);
                        }
                        printf("\n");
                }

                mwu += mw;
                spadu += spad;
                dbu += db;
                i++;
        }

        bus_attach_children(dev);
        return (0);
}

int
ntb_unregister_device(device_t dev)
{
        struct ntb_child **cpp = device_get_softc(dev);
        struct ntb_child *nc;
        int error = 0;

        while ((nc = *cpp) != NULL) {
                *cpp = (*cpp)->next;
                error = device_delete_child(dev, nc->dev);
                if (error)
                        break;
                rm_destroy(&nc->ctx_lock);
                free(nc, M_DEVBUF);
        }
        return (error);
}

int
ntb_child_location(device_t dev, device_t child, struct sbuf *sb)
{
        struct ntb_child *nc = device_get_ivars(child);

        sbuf_printf(sb, "function=%d", nc->function);
        return (0);
}

int
ntb_print_child(device_t dev, device_t child)
{
        struct ntb_child *nc = device_get_ivars(child);
        int retval;

        retval = bus_print_child_header(dev, child);
        if (nc->mwcnt > 0) {
                printf(" mw %d", nc->mwoff);
                if (nc->mwcnt > 1)
                        printf("-%d", nc->mwoff + nc->mwcnt - 1);
        }
        if (nc->spadcnt > 0) {
                printf(" spad %d", nc->spadoff);
                if (nc->spadcnt > 1)
                        printf("-%d", nc->spadoff + nc->spadcnt - 1);
        }
        if (nc->dbcnt > 0) {
                printf(" db %d", nc->dboff);
                if (nc->dbcnt > 1)
                        printf("-%d", nc->dboff + nc->dbcnt - 1);
        }
        retval += printf(" at function %d", nc->function);
        retval += bus_print_child_domain(dev, child);
        retval += bus_print_child_footer(dev, child);

        return (retval);
}

bus_dma_tag_t
ntb_get_dma_tag(device_t bus, device_t child)
{

        return (bus_get_dma_tag(bus));
}

void
ntb_link_event(device_t dev)
{
        struct ntb_child **cpp = device_get_softc(dev);
        struct ntb_child *nc;
        struct rm_priotracker ctx_tracker;
        enum ntb_speed speed;
        enum ntb_width width;

        if (NTB_LINK_IS_UP(dev, &speed, &width)) {
                device_printf(dev, "Link is up (PCIe %d.x / x%d)\n",
                    (int)speed, (int)width);
        } else {
                device_printf(dev, "Link is down\n");
        }
        for (nc = *cpp; nc != NULL; nc = nc->next) {
                rm_rlock(&nc->ctx_lock, &ctx_tracker);
                if (nc->ctx_ops != NULL && nc->ctx_ops->link_event != NULL)
                        nc->ctx_ops->link_event(nc->ctx);
                rm_runlock(&nc->ctx_lock, &ctx_tracker);
        }
}

void
ntb_db_event(device_t dev, uint32_t vec)
{
        struct ntb_child **cpp = device_get_softc(dev);
        struct ntb_child *nc;
        struct rm_priotracker ctx_tracker;

        for (nc = *cpp; nc != NULL; nc = nc->next) {
                rm_rlock(&nc->ctx_lock, &ctx_tracker);
                if (nc->ctx_ops != NULL && nc->ctx_ops->db_event != NULL)
                        nc->ctx_ops->db_event(nc->ctx, vec);
                rm_runlock(&nc->ctx_lock, &ctx_tracker);
        }
}

int
ntb_port_number(device_t ntb)
{
        return (NTB_PORT_NUMBER(device_get_parent(ntb)));
}

int
ntb_peer_port_count(device_t ntb)
{
        return (NTB_PEER_PORT_COUNT(device_get_parent(ntb)));
}

int
ntb_peer_port_number(device_t ntb, int pidx)
{
        return (NTB_PEER_PORT_NUMBER(device_get_parent(ntb), pidx));
}

int
ntb_peer_port_idx(device_t ntb, int port)
{
        return (NTB_PEER_PORT_IDX(device_get_parent(ntb), port));
}

bool
ntb_link_is_up(device_t ntb, enum ntb_speed *speed, enum ntb_width *width)
{

        return (NTB_LINK_IS_UP(device_get_parent(ntb), speed, width));
}

int
ntb_link_enable(device_t ntb, enum ntb_speed speed, enum ntb_width width)
{
        struct ntb_child *nc = device_get_ivars(ntb);
        struct ntb_child **cpp = device_get_softc(device_get_parent(nc->dev));
        struct ntb_child *nc1;

        for (nc1 = *cpp; nc1 != NULL; nc1 = nc1->next) {
                if (nc1->enabled) {
                        nc->enabled = 1;
                        return (0);
                }
        }
        nc->enabled = 1;
        return (NTB_LINK_ENABLE(device_get_parent(ntb), speed, width));
}

int
ntb_link_disable(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);
        struct ntb_child **cpp = device_get_softc(device_get_parent(nc->dev));
        struct ntb_child *nc1;

        if (!nc->enabled)
                return (0);
        nc->enabled = 0;
        for (nc1 = *cpp; nc1 != NULL; nc1 = nc1->next) {
                if (nc1->enabled)
                        return (0);
        }
        return (NTB_LINK_DISABLE(device_get_parent(ntb)));
}

bool
ntb_link_enabled(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (nc->enabled && NTB_LINK_ENABLED(device_get_parent(ntb)));
}

int
ntb_set_ctx(device_t ntb, void *ctx, const struct ntb_ctx_ops *ctx_ops)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        if (ctx == NULL || ctx_ops == NULL)
                return (EINVAL);

        rm_wlock(&nc->ctx_lock);
        if (nc->ctx_ops != NULL) {
                rm_wunlock(&nc->ctx_lock);
                return (EINVAL);
        }
        nc->ctx = ctx;
        nc->ctx_ops = ctx_ops;

        /*
         * If applicaiton driver asks for link events, generate fake one now
         * to let it update link state without races while we hold the lock.
         */
        if (ctx_ops->link_event != NULL)
                ctx_ops->link_event(ctx);
        rm_wunlock(&nc->ctx_lock);

        return (0);
}

void *
ntb_get_ctx(device_t ntb, const struct ntb_ctx_ops **ctx_ops)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        KASSERT(nc->ctx != NULL && nc->ctx_ops != NULL, ("bogus"));
        if (ctx_ops != NULL)
                *ctx_ops = nc->ctx_ops;
        return (nc->ctx);
}

void
ntb_clear_ctx(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        rm_wlock(&nc->ctx_lock);
        nc->ctx = NULL;
        nc->ctx_ops = NULL;
        rm_wunlock(&nc->ctx_lock);
}

uint8_t
ntb_mw_count(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (nc->mwcnt);
}

int
ntb_mw_get_range(device_t ntb, unsigned mw_idx, vm_paddr_t *base,
    caddr_t *vbase, size_t *size, size_t *align, size_t *align_size,
    bus_addr_t *plimit)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_MW_GET_RANGE(device_get_parent(ntb), mw_idx + nc->mwoff,
            base, vbase, size, align, align_size, plimit));
}

int
ntb_mw_set_trans(device_t ntb, unsigned mw_idx, bus_addr_t addr, size_t size)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_MW_SET_TRANS(device_get_parent(ntb), mw_idx + nc->mwoff,
            addr, size));
}

int
ntb_mw_clear_trans(device_t ntb, unsigned mw_idx)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_MW_CLEAR_TRANS(device_get_parent(ntb), mw_idx + nc->mwoff));
}

int
ntb_mw_get_wc(device_t ntb, unsigned mw_idx, vm_memattr_t *mode)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_MW_GET_WC(device_get_parent(ntb), mw_idx + nc->mwoff, mode));
}

int
ntb_mw_set_wc(device_t ntb, unsigned mw_idx, vm_memattr_t mode)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_MW_SET_WC(device_get_parent(ntb), mw_idx + nc->mwoff, mode));
}

uint8_t
ntb_spad_count(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (nc->spadcnt);
}

void
ntb_spad_clear(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);
        unsigned i;

        for (i = 0; i < nc->spadcnt; i++)
                NTB_SPAD_WRITE(device_get_parent(ntb), i + nc->spadoff, 0);
}

int
ntb_spad_write(device_t ntb, unsigned int idx, uint32_t val)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_SPAD_WRITE(device_get_parent(ntb), idx + nc->spadoff, val));
}

int
ntb_spad_read(device_t ntb, unsigned int idx, uint32_t *val)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_SPAD_READ(device_get_parent(ntb), idx + nc->spadoff, val));
}

int
ntb_peer_spad_write(device_t ntb, unsigned int idx, uint32_t val)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_PEER_SPAD_WRITE(device_get_parent(ntb), idx + nc->spadoff,
            val));
}

int
ntb_peer_spad_read(device_t ntb, unsigned int idx, uint32_t *val)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_PEER_SPAD_READ(device_get_parent(ntb), idx + nc->spadoff,
            val));
}

uint64_t
ntb_db_valid_mask(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (nc->dbmask);
}

int
ntb_db_vector_count(device_t ntb)
{

        return (NTB_DB_VECTOR_COUNT(device_get_parent(ntb)));
}

uint64_t
ntb_db_vector_mask(device_t ntb, uint32_t vector)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return ((NTB_DB_VECTOR_MASK(device_get_parent(ntb), vector)
            >> nc->dboff) & nc->dbmask);
}

int
ntb_peer_db_addr(device_t ntb, bus_addr_t *db_addr, vm_size_t *db_size)
{

        return (NTB_PEER_DB_ADDR(device_get_parent(ntb), db_addr, db_size));
}

void
ntb_db_clear(device_t ntb, uint64_t bits)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_DB_CLEAR(device_get_parent(ntb), bits << nc->dboff));
}

void
ntb_db_clear_mask(device_t ntb, uint64_t bits)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_DB_CLEAR_MASK(device_get_parent(ntb), bits << nc->dboff));
}

uint64_t
ntb_db_read(device_t ntb)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return ((NTB_DB_READ(device_get_parent(ntb)) >> nc->dboff)
            & nc->dbmask);
}

void
ntb_db_set_mask(device_t ntb, uint64_t bits)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_DB_SET_MASK(device_get_parent(ntb), bits << nc->dboff));
}

void
ntb_peer_db_set(device_t ntb, uint64_t bits)
{
        struct ntb_child *nc = device_get_ivars(ntb);

        return (NTB_PEER_DB_SET(device_get_parent(ntb), bits << nc->dboff));
}

MODULE_VERSION(ntb, 1);