/*
 * (MPSAFE)
 *
 * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 *
 * 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 The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
 * COPYRIGHT HOLDERS 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.
 */
/*
 * Primary device and CAM interface to OpenBSD SILI driver, for DragonFly
 */

#include "sili.h"

u_int32_t SiliForceGen1 = 0;
u_int32_t SiliNoFeatures = 0;

/*
 * Device bus methods
 */

static int      sili_probe (device_t dev);
static int      sili_attach (device_t dev);
static int      sili_detach (device_t dev);
#if 0
static int      sili_shutdown (device_t dev);
static int      sili_suspend (device_t dev);
static int      sili_resume (device_t dev);
#endif

static void     sili_port_thread(void *arg);

static device_method_t sili_methods[] = {
        DEVMETHOD(device_probe,         sili_probe),
        DEVMETHOD(device_attach,        sili_attach),
        DEVMETHOD(device_detach,        sili_detach),
#if 0
        DEVMETHOD(device_shutdown,      sili_shutdown),
        DEVMETHOD(device_suspend,       sili_suspend),
        DEVMETHOD(device_resume,        sili_resume),
#endif

        DEVMETHOD(bus_print_child,      bus_generic_print_child),
        DEVMETHOD(bus_driver_added,     bus_generic_driver_added),
        DEVMETHOD_END
};

static devclass_t       sili_devclass;

static driver_t sili_driver = {
        "sili",
        sili_methods,
        sizeof(struct sili_softc)
};

MODULE_DEPEND(sili, cam, 1, 1, 1);
DRIVER_MODULE(sili, pci, sili_driver, sili_devclass, NULL, NULL);

/*
 * Device bus method procedures
 */
static int
sili_probe (device_t dev)
{
        const struct sili_device *ad;

        if (kgetenv("hint.sili.disabled"))
                return(ENXIO);
        if (kgetenv("hint.sili.force150"))
                SiliForceGen1 = -1;
        if (kgetenv("hint.sili.nofeatures"))
                SiliNoFeatures = -1;

        ad = sili_lookup_device(dev);
        if (ad) {
                device_set_desc(dev, ad->name);
                return(-5);     /* higher priority the NATA */
        }
        return(ENXIO);
}

static int
sili_attach (device_t dev)
{
        struct sili_softc *sc = device_get_softc(dev);
        int error;

        sc->sc_ad = sili_lookup_device(dev);
        if (sc->sc_ad == NULL)
                return(ENXIO);
        error = sc->sc_ad->ad_attach(dev);
        return (error);
}

static int
sili_detach (device_t dev)
{
        struct sili_softc *sc = device_get_softc(dev);
        int error = 0;

        if (sc->sc_ad) {
                error = sc->sc_ad->ad_detach(dev);
                sc->sc_ad = NULL;
        }
        return(error);
}

#if 0

static int
sili_shutdown (device_t dev)
{
        return (0);
}

static int
sili_suspend (device_t dev)
{
        return (0);
}

static int
sili_resume (device_t dev)
{
        return (0);
}

#endif

/*
 * Sleep (ms) milliseconds, error on the side of caution.
 */
void
sili_os_sleep(int ms)
{
        int ticks;

        ticks = hz * ms / 1000 + 1;
        tsleep(&ticks, 0, "ahslp", ticks);
}

/*
 * Sleep for a minimum interval and return the number of milliseconds
 * that was.  The minimum value returned is 1
 */
int
sili_os_softsleep(void)
{
        if (hz >= 1000) {
                tsleep(&ticks, 0, "ahslp", hz / 1000);
                return(1);
        } else {
                tsleep(&ticks, 0, "ahslp", 1);
                return(1000 / hz);
        }
}

void
sili_os_hardsleep(int us)
{
        DELAY(us);
}

/*
 * Create the OS-specific port helper thread and per-port lock.
 */
void
sili_os_start_port(struct sili_port *ap)
{
        atomic_set_int(&ap->ap_signal, AP_SIGF_INIT);
        lockinit(&ap->ap_lock, "silipo", 0, LK_CANRECURSE);
        lockinit(&ap->ap_sim_lock, "silicam", 0, LK_CANRECURSE);
        lockinit(&ap->ap_sig_lock, "siport", 0, 0);
        kthread_create(sili_port_thread, ap, &ap->ap_thread,
                       "%s", PORTNAME(ap));
}

/*
 * Stop the OS-specific port helper thread and kill the per-port lock.
 */
void
sili_os_stop_port(struct sili_port *ap)
{
        if (ap->ap_thread) {
                sili_os_signal_port_thread(ap, AP_SIGF_STOP);
                sili_os_sleep(10);
                if (ap->ap_thread) {
                        kprintf("%s: Waiting for thread to terminate\n",
                                PORTNAME(ap));
                        while (ap->ap_thread)
                                sili_os_sleep(100);
                        kprintf("%s: thread terminated\n",
                                PORTNAME(ap));
                }
        }
        lockuninit(&ap->ap_lock);
}

/*
 * Add (mask) to the set of bits being sent to the per-port thread helper
 * and wake the helper up if necessary.
 */
void
sili_os_signal_port_thread(struct sili_port *ap, int mask)
{
        lockmgr(&ap->ap_sig_lock, LK_EXCLUSIVE);
        atomic_set_int(&ap->ap_signal, mask);
        wakeup(&ap->ap_thread);
        lockmgr(&ap->ap_sig_lock, LK_RELEASE);
}

/*
 * Unconditionally lock the port structure for access.
 */
void
sili_os_lock_port(struct sili_port *ap)
{
        lockmgr(&ap->ap_lock, LK_EXCLUSIVE);
}

/*
 * Conditionally lock the port structure for access.
 *
 * Returns 0 on success, non-zero on failure.
 */
int
sili_os_lock_port_nb(struct sili_port *ap)
{
        return (lockmgr(&ap->ap_lock, LK_EXCLUSIVE | LK_NOWAIT));
}

/*
 * Unlock a previously locked port.
 */
void
sili_os_unlock_port(struct sili_port *ap)
{
        lockmgr(&ap->ap_lock, LK_RELEASE);
}

/*
 * Per-port thread helper.  This helper thread is responsible for
 * atomically retrieving and clearing the signal mask and calling
 * the machine-independant driver core.
 *
 * MPSAFE
 */
static
void
sili_port_thread(void *arg)
{
        struct sili_port *ap = arg;
        int mask;

        /*
         * The helper thread is responsible for the initial port init,
         * so all the ports can be inited in parallel.
         *
         * We also run the state machine which should do all probes.
         * Since CAM is not attached yet we will not get out-of-order
         * SCSI attachments.
         */
        sili_os_lock_port(ap);
        sili_port_init(ap);
        sili_port_state_machine(ap, 1);
        sili_os_unlock_port(ap);
        atomic_clear_int(&ap->ap_signal, AP_SIGF_INIT);
        wakeup(&ap->ap_signal);

        /*
         * Then loop on the helper core.
         */
        mask = ap->ap_signal;
        while ((mask & AP_SIGF_STOP) == 0) {
                atomic_clear_int(&ap->ap_signal, mask);
                sili_port_thread_core(ap, mask);
                lockmgr(&ap->ap_sig_lock, LK_EXCLUSIVE);
                if (ap->ap_signal == 0) {
                        lksleep(&ap->ap_thread, &ap->ap_sig_lock, 0,
                                "siport", 0);
                }
                lockmgr(&ap->ap_sig_lock, LK_RELEASE);
                mask = ap->ap_signal;
        }
        ap->ap_thread = NULL;
}