/*-
 * Copyright (c) 1997, Stefan Esser <se@kfreebsd.org>
 * Copyright (c) 2000, Michael Smith <msmith@kfreebsd.org>
 * Copyright (c) 2000, BSDi
 * 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 unmodified, 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 ``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 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.
 *
 * $FreeBSD: src/sys/dev/acpica/acpi_pci.c,v 1.31.2.1.6.1 2009/04/15 03:14:26 kensmith Exp $
 */

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

#include "acpi.h"
#include "acpivar.h"

#include <sys/pciio.h>
#include <bus/pci/pcireg.h>
#include <bus/pci/pcivar.h>
#include <bus/pci/pci_private.h>

/* Hooks for the ACPICA debugging infrastructure. */
#define _COMPONENT      ACPI_BUS
ACPI_MODULE_NAME("PCI")

struct acpi_pci_devinfo {
        struct pci_devinfo      ap_dinfo;
        ACPI_HANDLE             ap_handle;
        int                     ap_flags;
};

ACPI_SERIAL_DECL(pci_powerstate, "ACPI PCI power methods");

/* Be sure that ACPI and PCI power states are equivalent. */
CTASSERT(ACPI_STATE_D0 == PCI_POWERSTATE_D0);
CTASSERT(ACPI_STATE_D1 == PCI_POWERSTATE_D1);
CTASSERT(ACPI_STATE_D2 == PCI_POWERSTATE_D2);
CTASSERT(ACPI_STATE_D3 == PCI_POWERSTATE_D3);

static int      acpi_pci_attach(device_t dev);
static int      acpi_pci_suspend(device_t dev);
static int      acpi_pci_resume(device_t dev);
static int      acpi_pci_child_location_str_method(device_t cbdev,
                    device_t child, char *buf, size_t buflen);
static int      acpi_pci_probe(device_t dev);
static int      acpi_pci_read_ivar(device_t dev, device_t child, int which,
                    uintptr_t *result);
static int      acpi_pci_write_ivar(device_t dev, device_t child, int which,
                    uintptr_t value);
static ACPI_STATUS acpi_pci_save_handle(ACPI_HANDLE handle, UINT32 level,
                    void *context, void **status);
static int      acpi_pci_set_powerstate_method(device_t dev, device_t child,
                    int state);
static void     acpi_pci_update_device(ACPI_HANDLE handle, device_t pci_child);

static device_method_t acpi_pci_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         acpi_pci_probe),
        DEVMETHOD(device_attach,        acpi_pci_attach),
        DEVMETHOD(device_suspend,       acpi_pci_suspend),
        DEVMETHOD(device_resume,        acpi_pci_resume),

        /* Bus interface */
        DEVMETHOD(bus_read_ivar,        acpi_pci_read_ivar),
        DEVMETHOD(bus_write_ivar,       acpi_pci_write_ivar),
        DEVMETHOD(bus_child_location_str, acpi_pci_child_location_str_method),

        /* PCI interface */
        DEVMETHOD(pci_set_powerstate,   acpi_pci_set_powerstate_method),

        DEVMETHOD_END
};

static devclass_t pci_devclass;

DEFINE_CLASS_1(pci, acpi_pci_driver, acpi_pci_methods, 0, pci_driver);
DRIVER_MODULE(acpi_pci, pcib, acpi_pci_driver, pci_devclass, NULL, NULL);
MODULE_DEPEND(acpi_pci, acpi, 1, 1, 1);
MODULE_DEPEND(acpi_pci, pci, 1, 1, 1);
MODULE_VERSION(acpi_pci, 1);

static int
acpi_pci_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
{
    struct acpi_pci_devinfo *dinfo;

    dinfo = device_get_ivars(child);
    switch (which) {
    case ACPI_IVAR_HANDLE:
        *result = (uintptr_t)dinfo->ap_handle;
        return (0);
    case ACPI_IVAR_FLAGS:
        *result = (uintptr_t)dinfo->ap_flags;
        return (0);
    }
    return (pci_read_ivar(dev, child, which, result));
}

static int
acpi_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
{
    struct acpi_pci_devinfo *dinfo;

    dinfo = device_get_ivars(child);
    switch (which) {
    case ACPI_IVAR_HANDLE:
        dinfo->ap_handle = (ACPI_HANDLE)value;
        return (0);
    case ACPI_IVAR_FLAGS:
        dinfo->ap_flags = (int)value;
        return (0);
    }
    return (pci_write_ivar(dev, child, which, value));
}

static int
acpi_pci_child_location_str_method(device_t cbdev, device_t child, char *buf,
    size_t buflen)
{
    struct acpi_pci_devinfo *dinfo = device_get_ivars(child);

    pci_child_location_str_method(cbdev, child, buf, buflen);

    if (dinfo->ap_handle) {
        strlcat(buf, " handle=", buflen);
        strlcat(buf, acpi_name(dinfo->ap_handle), buflen);
    }
    return (0);
}

/*
 * PCI power manangement
 */
static int
acpi_pci_set_powerstate_method(device_t dev, device_t child, int state)
{
        ACPI_HANDLE h;
        ACPI_STATUS status;
        int old_state, error;

        error = 0;
        if (state < ACPI_STATE_D0 || state > ACPI_STATE_D3)
                return (EINVAL);

        /*
         * We set the state using PCI Power Management outside of setting
         * the ACPI state.  This means that when powering down a device, we
         * first shut it down using PCI, and then using ACPI, which lets ACPI
         * try to power down any Power Resources that are now no longer used.
         * When powering up a device, we let ACPI set the state first so that
         * it can enable any needed Power Resources before changing the PCI
         * power state.
         */
        ACPI_SERIAL_BEGIN(pci_powerstate);
        old_state = pci_get_powerstate(child);
        if (old_state < state) {
                error = pci_set_powerstate_method(dev, child, state);
                if (error)
                        goto out;
        }
        h = acpi_get_handle(child);
        status = acpi_pwr_switch_consumer(h, state);
        if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
                device_printf(dev,
                    "Failed to set ACPI power state %s on %s: %s\n",
                    acpi_d_state_to_str(state), acpi_name(h),
                    AcpiFormatException(status));
        if (old_state > state)
                error = pci_set_powerstate_method(dev, child, state);

out:
        ACPI_SERIAL_END(pci_powerstate);
        return (error);
}

static void
acpi_pci_update_device(ACPI_HANDLE handle, device_t pci_child)
{
        ACPI_STATUS status;
        device_t child;

        /*
         * Lookup and remove the unused device that acpi0 creates when it walks
         * the namespace creating devices.
         */
        child = acpi_get_device(handle);
        if (child != NULL) {
                if (device_is_alive(child)) {
                        /*
                         * The TabletPC TC1000 has a second PCI-ISA bridge
                         * that has a _HID for an acpi_sysresource device.
                         * In that case, leave ACPICA's device data pointing
                         * at the ACPI-enumerated device.
                         */
                        device_printf(child,
                            "Conflicts with PCI device %d:%d:%d\n",
                            pci_get_bus(pci_child), pci_get_slot(pci_child),
                            pci_get_function(pci_child));
                        return;
                }
                KASSERT(device_get_parent(child) ==
                    devclass_get_device(devclass_find("acpi"), 0),
                    ("%s: child (%s)'s parent is not acpi0", __func__,
                    acpi_name(handle)));
                device_delete_child(device_get_parent(child), child);
        }

        /*
         * Update ACPICA to use the PCI enumerated device_t for this handle.
         */
        status = AcpiDetachData(handle, acpi_fake_objhandler);
        if (ACPI_FAILURE(status))
                kprintf("WARNING: Unable to detach object data from %s - %s\n",
                    acpi_name(handle), AcpiFormatException(status));
        status = AcpiAttachData(handle, acpi_fake_objhandler, pci_child);
        if (ACPI_FAILURE(status))
                kprintf("WARNING: Unable to attach object data to %s - %s\n",
                    acpi_name(handle), AcpiFormatException(status));
}

static ACPI_STATUS
acpi_pci_save_handle(ACPI_HANDLE handle, UINT32 level, void *context,
    void **status)
{
        struct acpi_pci_devinfo *dinfo;
        device_t *devlist;
        int devcount, i, func, slot;
        UINT32 address;

        ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);

        if (ACPI_FAILURE(acpi_GetInteger(handle, "_ADR", &address)))
                return_ACPI_STATUS (AE_OK);
        slot = ACPI_ADR_PCI_SLOT(address);
        func = ACPI_ADR_PCI_FUNC(address);
        if (device_get_children((device_t)context, &devlist, &devcount) != 0)
                return_ACPI_STATUS (AE_OK);
        for (i = 0; i < devcount; i++) {
                dinfo = device_get_ivars(devlist[i]);
                if (dinfo->ap_dinfo.cfg.func == func &&
                    dinfo->ap_dinfo.cfg.slot == slot) {
                        dinfo->ap_handle = handle;
                        acpi_pci_update_device(handle, devlist[i]);
                        break;
                }
        }
        kfree(devlist, M_TEMP);
        return_ACPI_STATUS (AE_OK);
}

static int
acpi_pci_probe(device_t dev)
{
        if (acpi_get_handle(dev) == NULL)
                return (ENXIO);
        device_set_desc(dev, "ACPI PCI bus");
        return (0);
}

static int
acpi_pci_attach(device_t dev)
{
        int busno, domain;

        /*
         * Since there can be multiple independantly numbered PCI
         * busses on systems with multiple PCI domains, we can't use
         * the unit number to decide which bus we are probing. We ask
         * the parent pcib what our domain and bus numbers are.
         */
        busno = pcib_get_bus(dev);
        domain = pcib_get_domain(dev);
        if (bootverbose) {
                device_printf(dev, "domain=%d, physical bus=%d\n",
                    domain, busno);
        }

        ACPI_SERIAL_INIT(pci_powerstate);

        /*
         * First, PCI devices are added as in the normal PCI bus driver.
         * Afterwards, the ACPI namespace under the bridge driver is
         * walked to save ACPI handles to all the devices that appear in
         * the ACPI namespace as immediate descendants of the bridge.
         *
         * XXX: Sometimes PCI devices show up in the ACPI namespace that
         * pci_add_children() doesn't find.  We currently just ignore
         * these devices.
         */
        pci_add_children(dev, domain, busno, sizeof(struct acpi_pci_devinfo));
        AcpiWalkNamespace(ACPI_TYPE_DEVICE, acpi_get_handle(dev), 1,
            acpi_pci_save_handle, NULL, dev, NULL);

        return (bus_generic_attach(dev));
}

static int
acpi_pci_suspend(device_t dev)
{
        int dstate, error, i, numdevs;
        device_t acpi_dev, child, *devlist;
        struct pci_devinfo *dinfo;

        acpi_dev = devclass_get_device(devclass_find("acpi"), 0);
        device_get_children(dev, &devlist, &numdevs);

        /*
         * Save the PCI configuration space for each child and set the
         * device in the appropriate power state for this sleep state.
         */
        for (i = 0; i < numdevs; i++) {
                child = devlist[i];
                dinfo = (struct pci_devinfo *)device_get_ivars(child);
                pci_cfg_save(child, dinfo, 0);
        }

        /*
         * Suspend devices before potentially powering them down.
         */
        error = bus_generic_suspend(dev);
        if (error) {
                kfree(devlist, M_TEMP);
                return (error);
        }

        /*
         * Always set the device to D3.  If ACPI suggests a different
         * power state, use it instead.  If ACPI is not present, the
         * firmware is responsible for managing device power.  Skip
         * children who aren't attached since they are powered down
         * separately.  Only manage type 0 devices for now.
         */
        for (i = 0; acpi_dev && i < numdevs; i++) {
                child = devlist[i];
                dinfo = (struct pci_devinfo *)device_get_ivars(child);
                if (device_is_attached(child) && dinfo->cfg.hdrtype == 0) {
                        dstate = PCI_POWERSTATE_D3;
                        ACPI_PWR_FOR_SLEEP(acpi_dev, child, &dstate);
                        pci_set_powerstate(child, dstate);
                }
        }

        kfree(devlist, M_TEMP);
        return (0);
}

static int
acpi_pci_resume(device_t dev)
{
        int i, numdevs;
        device_t acpi_dev, child, *devlist;
        struct pci_devinfo *dinfo;

        acpi_dev = devclass_get_device(devclass_find("acpi"), 0);
        device_get_children(dev, &devlist, &numdevs);

        /*
         * Set each child to D0 and restore its PCI configuration space.
         */
        for (i = 0; i < numdevs; i++) {
                /*
                 * Notify ACPI we're going to D0 but ignore the result.  If
                 * ACPI is not present, the firmware is responsible for
                 * managing device power.  Only manage type 0 devices for now.
                 */
                child = devlist[i];
                dinfo = (struct pci_devinfo *) device_get_ivars(child);
                if (acpi_dev && device_is_attached(child) &&
                    dinfo->cfg.hdrtype == 0) {
                        ACPI_PWR_FOR_SLEEP(acpi_dev, child, NULL);
                        pci_set_powerstate(child, PCI_POWERSTATE_D0);
                }

                /*
                 * Now the device is powered up, restore its config space.
                 */
                pci_cfg_restore(child, dinfo);
        }

        kfree(devlist, M_TEMP);
        return (bus_generic_resume(dev));
}