/*
 * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
 * 
 * This code is derived from software contributed to The DragonFly Project
 * by Sepherosa Ziehau <sepherosa@gmail.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.
 */

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/interrupt.h>
#include <sys/kernel.h>
#include <sys/machintr.h>
#include <sys/systm.h>

#include <contrib/dev/acpica/source/include/acpi.h>

#include "acpi_sdt_var.h"
#include "acpi_sci_var.h"

#define FADT_VPRINTF(fmt, arg...) \
do { \
        if (bootverbose) \
                kprintf("ACPI FADT: " fmt , ##arg); \
} while (0)

struct acpi_sci_mode {
        enum intr_trigger       sci_trig;
        enum intr_polarity      sci_pola;
};

static int                      acpi_sci_irq = -1;
static enum intr_trigger        acpi_sci_trig = INTR_TRIGGER_CONFORM;
static enum intr_polarity       acpi_sci_pola = INTR_POLARITY_CONFORM;
static const struct acpi_sci_mode *acpi_sci_mode1 = NULL;

static const struct acpi_sci_mode acpi_sci_modes[] = {
        /*
         * NOTE: Order is critical
         */
        { INTR_TRIGGER_LEVEL,   INTR_POLARITY_LOW },
        { INTR_TRIGGER_LEVEL,   INTR_POLARITY_HIGH },
        { INTR_TRIGGER_EDGE,    INTR_POLARITY_HIGH },
        { INTR_TRIGGER_EDGE,    INTR_POLARITY_LOW },

        /* Required last entry */
        { INTR_TRIGGER_CONFORM, INTR_POLARITY_CONFORM }
};

/*
 * Set to 1 to stop atkbdc from being configured early, via cninit().
 *
 * Currently set to 0 because this is causing problems for several
 * people.  Can be set to 1 with a tunable.
 */
int acpi_fadt_8042_nolegacy = 0;
TUNABLE_INT("hw.acpi.fadt_8042_nolegacy", &acpi_fadt_8042_nolegacy);

static void
fadt_probe(void)
{
        ACPI_TABLE_FADT *fadt;
        vm_paddr_t fadt_paddr;
        enum intr_trigger trig;
        enum intr_polarity pola;
        int enabled = 1;
        char *env;

        fadt_paddr = sdt_search(ACPI_SIG_FADT);
        if (fadt_paddr == 0) {
                acpi_fadt_8042_nolegacy = 0;
                kprintf("fadt_probe: can't locate FADT\n");
                return;
        }

        fadt = sdt_sdth_map(fadt_paddr);
        KKASSERT(fadt != NULL);

        /*
         * FADT in ACPI specification 1.0 - 6.0
         */
        if (fadt->Header.Revision < 1 || fadt->Header.Revision > 6) {
                kprintf("fadt_probe: unknown FADT revision %d\n",
                        fadt->Header.Revision);
        }

        if (fadt->Header.Length < ACPI_FADT_V1_SIZE) {
                acpi_fadt_8042_nolegacy = 0;
                kprintf("fadt_probe: invalid FADT length %u (< %u)\n",
                    fadt->Header.Length, ACPI_FADT_V1_SIZE);
                goto back;
        }

        if (fadt->Header.Length >= ACPI_FADT_V3_SIZE &&
            fadt->Header.Revision >= 3) {
                if ((fadt->BootFlags & ACPI_FADT_8042) != 0)
                        acpi_fadt_8042_nolegacy = 0;
        } else {
                acpi_fadt_8042_nolegacy = 0;
        }

        kgetenv_int("hw.acpi.sci.enabled", &enabled);
        if (!enabled)
                goto back;

        acpi_sci_irq = fadt->SciInterrupt;

        env = kgetenv("hw.acpi.sci.trigger");
        if (env == NULL)
                goto back;

        trig = INTR_TRIGGER_CONFORM;
        if (strcmp(env, "edge") == 0)
                trig = INTR_TRIGGER_EDGE;
        else if (strcmp(env, "level") == 0)
                trig = INTR_TRIGGER_LEVEL;

        kfreeenv(env);

        if (trig == INTR_TRIGGER_CONFORM)
                goto back;

        env = kgetenv("hw.acpi.sci.polarity");
        if (env == NULL)
                goto back;

        pola = INTR_POLARITY_CONFORM;
        if (strcmp(env, "high") == 0)
                pola = INTR_POLARITY_HIGH;
        else if (strcmp(env, "low") == 0)
                pola = INTR_POLARITY_LOW;

        kfreeenv(env);

        if (pola == INTR_POLARITY_CONFORM)
                goto back;

        acpi_sci_trig = trig;
        acpi_sci_pola = pola;
back:
        if (acpi_sci_irq >= 0) {
                FADT_VPRINTF("SCI irq %d, %s/%s\n", acpi_sci_irq,
                             intr_str_trigger(acpi_sci_trig),
                             intr_str_polarity(acpi_sci_pola));
        } else {
                FADT_VPRINTF("SCI is disabled\n");
        }
        sdt_sdth_unmap(&fadt->Header);
}
SYSINIT(fadt_probe, SI_BOOT2_PRESMP, SI_ORDER_SECOND, fadt_probe, 0);

static void
acpi_sci_dummy_intr(void *dummy __unused, void *frame __unused)
{
}

static boolean_t
acpi_sci_test(const struct acpi_sci_mode *mode)
{
        void *sci_desc;
        long last_cnt;

        FADT_VPRINTF("SCI testing %s/%s\n",
            intr_str_trigger(mode->sci_trig),
            intr_str_polarity(mode->sci_pola));

        last_cnt = get_interrupt_counter(acpi_sci_irq, 0);

        machintr_legacy_intr_config(acpi_sci_irq,
            mode->sci_trig, mode->sci_pola);

        sci_desc = register_int(acpi_sci_irq,
            acpi_sci_dummy_intr, NULL, "sci", NULL,
            INTR_EXCL | INTR_CLOCK |
            INTR_NOPOLL | INTR_MPSAFE | INTR_NOENTROPY, 0);

        DELAY(100 * 1000);

        unregister_int(sci_desc, 0);

        if (get_interrupt_counter(acpi_sci_irq, 0) - last_cnt < 20) {
                acpi_sci_trig = mode->sci_trig;
                acpi_sci_pola = mode->sci_pola;

                kprintf("ACPI FADT: SCI select %s/%s\n",
                    intr_str_trigger(acpi_sci_trig),
                    intr_str_polarity(acpi_sci_pola));
                return TRUE;
        }
        return FALSE;
}

void
acpi_sci_config(void)
{
        const struct acpi_sci_mode *mode;

        KKASSERT(mycpuid == 0);

        if (machintr_legacy_intr_find(acpi_sci_irq,
            INTR_TRIGGER_CONFORM, INTR_POLARITY_CONFORM) < 0) {
                kprintf("ACPI FADT: SCI irq %d is invalid, disable\n",
                    acpi_sci_irq);
                acpi_sci_irq = -1;
                return;
        }

        if (acpi_sci_irq < 0)
                return;

        if (acpi_sci_trig != INTR_TRIGGER_CONFORM) {
                KKASSERT(acpi_sci_pola != INTR_POLARITY_CONFORM);
                machintr_legacy_intr_config(acpi_sci_irq,
                    acpi_sci_trig, acpi_sci_pola);
                return;
        }

        kprintf("ACPI FADT: SCI testing interrupt mode ...\n");
        if (acpi_sci_mode1 != NULL) {
                if (acpi_sci_test(acpi_sci_mode1))
                        return;
        }
        for (mode = acpi_sci_modes; mode->sci_trig != INTR_TRIGGER_CONFORM;
             ++mode) {
                if (mode == acpi_sci_mode1)
                        continue;
                if (acpi_sci_test(mode))
                        return;
        }

        kprintf("ACPI FADT: no suitable interrupt mode for SCI, disable\n");
        acpi_sci_irq = -1;
}

int
acpi_sci_enabled(void)
{
        if (acpi_sci_irq >= 0)
                return 1;
        else
                return 0;
}

int
acpi_sci_pci_shareable(void)
{
        if (acpi_sci_irq >= 0 &&
            acpi_sci_trig == INTR_TRIGGER_LEVEL &&
            acpi_sci_pola == INTR_POLARITY_LOW)
                return 1;
        else
                return 0;
}

int
acpi_sci_irqno(void)
{
        return acpi_sci_irq;
}

void
acpi_sci_setmode1(enum intr_trigger trig, enum intr_polarity pola)
{
        const struct acpi_sci_mode *mode;

        for (mode = acpi_sci_modes; mode->sci_trig != INTR_TRIGGER_CONFORM;
             ++mode) {
                if (mode->sci_trig == trig && mode->sci_pola == pola) {
                        acpi_sci_mode1 = mode;
                        return;
                }
        }
}