/*
 * 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;
		}
	}
}