/*-
 * Copyright (c) 2015-2016 Mellanox Technologies, Ltd.
 * All rights reserved.
 * Copyright (c) 2020-2025 The FreeBSD Foundation
 *
 * Portions of this software were developed by Björn Zeeb
 * under sponsorship from the FreeBSD Foundation.
 *
 * 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.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/filio.h>
#include <sys/pciio.h>
#include <sys/pctrie.h>
#include <sys/rman.h>
#include <sys/rwlock.h>
#include <sys/stdarg.h>

#include <vm/vm.h>
#include <vm/pmap.h>

#include <machine/bus.h>
#include <machine/resource.h>

#include <dev/pci/pcivar.h>
#include <dev/pci/pci_private.h>
#include <dev/pci/pci_iov.h>
#include <dev/backlight/backlight.h>

#include <linux/kernel.h>
#include <linux/kobject.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/cdev.h>
#include <linux/file.h>
#include <linux/sysfs.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/vmalloc.h>
#define WANT_NATIVE_PCI_GET_SLOT
#include <linux/pci.h>
#include <linux/compat.h>

#include <linux/backlight.h>

#include "backlight_if.h"
#include "pcib_if.h"

/* Undef the linux function macro defined in linux/pci.h */
#undef pci_get_class

extern int linuxkpi_debug;

SYSCTL_DECL(_compat_linuxkpi);

static counter_u64_t lkpi_pci_nseg1_fail;
SYSCTL_COUNTER_U64(_compat_linuxkpi, OID_AUTO, lkpi_pci_nseg1_fail, CTLFLAG_RD,
    &lkpi_pci_nseg1_fail, "Count of busdma mapping failures of single-segment");

static device_probe_t linux_pci_probe;
static device_attach_t linux_pci_attach;
static device_detach_t linux_pci_detach;
static device_suspend_t linux_pci_suspend;
static device_resume_t linux_pci_resume;
static device_shutdown_t linux_pci_shutdown;
static pci_iov_init_t linux_pci_iov_init;
static pci_iov_uninit_t linux_pci_iov_uninit;
static pci_iov_add_vf_t linux_pci_iov_add_vf;
static int linux_backlight_get_status(device_t dev, struct backlight_props *props);
static int linux_backlight_update_status(device_t dev, struct backlight_props *props);
static int linux_backlight_get_info(device_t dev, struct backlight_info *info);
static void lkpi_pcim_iomap_table_release(struct device *, void *);

static device_method_t pci_methods[] = {
        DEVMETHOD(device_probe, linux_pci_probe),
        DEVMETHOD(device_attach, linux_pci_attach),
        DEVMETHOD(device_detach, linux_pci_detach),
        DEVMETHOD(device_suspend, linux_pci_suspend),
        DEVMETHOD(device_resume, linux_pci_resume),
        DEVMETHOD(device_shutdown, linux_pci_shutdown),
        DEVMETHOD(pci_iov_init, linux_pci_iov_init),
        DEVMETHOD(pci_iov_uninit, linux_pci_iov_uninit),
        DEVMETHOD(pci_iov_add_vf, linux_pci_iov_add_vf),

        /* Bus interface. */
        DEVMETHOD(bus_add_child, bus_generic_add_child),

        /* backlight interface */
        DEVMETHOD(backlight_update_status, linux_backlight_update_status),
        DEVMETHOD(backlight_get_status, linux_backlight_get_status),
        DEVMETHOD(backlight_get_info, linux_backlight_get_info),
        DEVMETHOD_END
};

const char *pci_power_names[] = {
        "UNKNOWN", "D0", "D1", "D2", "D3hot", "D3cold"
};

/* We need some meta-struct to keep track of these for devres. */
struct pci_devres {
        bool            enable_io;
        /* PCIR_MAX_BAR_0 + 1 = 6 => BIT(0..5). */
        uint8_t         region_mask;
        struct resource *region_table[PCIR_MAX_BAR_0 + 1]; /* Not needed. */
};
struct pcim_iomap_devres {
        void            *mmio_table[PCIR_MAX_BAR_0 + 1];
        struct resource *res_table[PCIR_MAX_BAR_0 + 1];
};

struct linux_dma_priv {
        uint64_t        dma_mask;
        bus_dma_tag_t   dmat;
        uint64_t        dma_coherent_mask;
        bus_dma_tag_t   dmat_coherent;
        struct mtx      lock;
        struct pctrie   ptree;
};
#define DMA_PRIV_LOCK(priv) mtx_lock(&(priv)->lock)
#define DMA_PRIV_UNLOCK(priv) mtx_unlock(&(priv)->lock)

static void
lkpi_set_pcim_iomap_devres(struct pcim_iomap_devres *dr, int bar,
    void *res)
{
        dr->mmio_table[bar] = (void *)rman_get_bushandle(res);
        dr->res_table[bar] = res;
}

static bool
lkpi_pci_bar_id_valid(int bar)
{
        if (bar < 0 || bar > PCIR_MAX_BAR_0)
                return (false);

        return (true);
}

static int
linux_pdev_dma_uninit(struct pci_dev *pdev)
{
        struct linux_dma_priv *priv;

        priv = pdev->dev.dma_priv;
        if (priv->dmat)
                bus_dma_tag_destroy(priv->dmat);
        if (priv->dmat_coherent)
                bus_dma_tag_destroy(priv->dmat_coherent);
        mtx_destroy(&priv->lock);
        pdev->dev.dma_priv = NULL;
        free(priv, M_DEVBUF);
        return (0);
}

static int
linux_pdev_dma_init(struct pci_dev *pdev)
{
        struct linux_dma_priv *priv;
        int error;

        priv = malloc(sizeof(*priv), M_DEVBUF, M_WAITOK | M_ZERO);

        mtx_init(&priv->lock, "lkpi-priv-dma", NULL, MTX_DEF);
        pctrie_init(&priv->ptree);

        pdev->dev.dma_priv = priv;

        /* Create a default DMA tags. */
        error = linux_dma_tag_init(&pdev->dev, DMA_BIT_MASK(64));
        if (error != 0)
                goto err;
        /* Coherent is lower 32bit only by default in Linux. */
        error = linux_dma_tag_init_coherent(&pdev->dev, DMA_BIT_MASK(32));
        if (error != 0)
                goto err;

        return (error);

err:
        linux_pdev_dma_uninit(pdev);
        return (error);
}

int
linux_dma_tag_init(struct device *dev, u64 dma_mask)
{
        struct linux_dma_priv *priv;
        int error;

        priv = dev->dma_priv;

        if (priv->dmat) {
                if (priv->dma_mask == dma_mask)
                        return (0);

                bus_dma_tag_destroy(priv->dmat);
        }

        priv->dma_mask = dma_mask;

        error = bus_dma_tag_create(bus_get_dma_tag(dev->bsddev),
            1, 0,                       /* alignment, boundary */
            dma_mask,                   /* lowaddr */
            BUS_SPACE_MAXADDR,          /* highaddr */
            NULL, NULL,                 /* filtfunc, filtfuncarg */
            BUS_SPACE_MAXSIZE,          /* maxsize */
            1,                          /* nsegments */
            BUS_SPACE_MAXSIZE,          /* maxsegsz */
            0,                          /* flags */
            NULL, NULL,                 /* lockfunc, lockfuncarg */
            &priv->dmat);
        return (-error);
}

int
linux_dma_tag_init_coherent(struct device *dev, u64 dma_mask)
{
        struct linux_dma_priv *priv;
        int error;

        priv = dev->dma_priv;

        if (priv->dmat_coherent) {
                if (priv->dma_coherent_mask == dma_mask)
                        return (0);

                bus_dma_tag_destroy(priv->dmat_coherent);
        }

        priv->dma_coherent_mask = dma_mask;

        error = bus_dma_tag_create(bus_get_dma_tag(dev->bsddev),
            1, 0,                       /* alignment, boundary */
            dma_mask,                   /* lowaddr */
            BUS_SPACE_MAXADDR,          /* highaddr */
            NULL, NULL,                 /* filtfunc, filtfuncarg */
            BUS_SPACE_MAXSIZE,          /* maxsize */
            1,                          /* nsegments */
            BUS_SPACE_MAXSIZE,          /* maxsegsz */
            0,                          /* flags */
            NULL, NULL,                 /* lockfunc, lockfuncarg */
            &priv->dmat_coherent);
        return (-error);
}

static struct pci_driver *
linux_pci_find(device_t dev, const struct pci_device_id **idp)
{
        const struct pci_device_id *id;
        struct pci_driver *pdrv;
        uint16_t vendor;
        uint16_t device;
        uint16_t subvendor;
        uint16_t subdevice;

        vendor = pci_get_vendor(dev);
        device = pci_get_device(dev);
        subvendor = pci_get_subvendor(dev);
        subdevice = pci_get_subdevice(dev);

        spin_lock(&pci_lock);
        list_for_each_entry(pdrv, &pci_drivers, node) {
                for (id = pdrv->id_table; id->vendor != 0; id++) {
                        if (vendor == id->vendor &&
                            (PCI_ANY_ID == id->device || device == id->device) &&
                            (PCI_ANY_ID == id->subvendor || subvendor == id->subvendor) &&
                            (PCI_ANY_ID == id->subdevice || subdevice == id->subdevice)) {
                                *idp = id;
                                spin_unlock(&pci_lock);
                                return (pdrv);
                        }
                }
        }
        spin_unlock(&pci_lock);
        return (NULL);
}

struct pci_dev *
lkpi_pci_get_device(uint32_t vendor, uint32_t device, struct pci_dev *odev)
{
        struct pci_dev *pdev, *found;

        found = NULL;
        spin_lock(&pci_lock);
        list_for_each_entry(pdev, &pci_devices, links) {
                /* Walk until we find odev. */
                if (odev != NULL) {
                        if (pdev == odev)
                                odev = NULL;
                        continue;
                }

                if ((pdev->vendor == vendor || vendor == PCI_ANY_ID) &&
                    (pdev->device == device || device == PCI_ANY_ID)) {
                        found = pdev;
                        break;
                }
        }
        pci_dev_get(found);
        spin_unlock(&pci_lock);

        return (found);
}

static void
lkpi_pci_dev_release(struct device *dev)
{

        lkpi_devres_release_free_list(dev);
        spin_lock_destroy(&dev->devres_lock);
}

static int
lkpifill_pci_dev(device_t dev, struct pci_dev *pdev)
{
        struct pci_devinfo *dinfo;
        int error;

        error = kobject_init_and_add(&pdev->dev.kobj, &linux_dev_ktype,
            &linux_root_device.kobj, device_get_nameunit(dev));
        if (error != 0) {
                printf("%s:%d: kobject_init_and_add returned %d\n",
                    __func__, __LINE__, error);
                return (error);
        }

        pdev->devfn = PCI_DEVFN(pci_get_slot(dev), pci_get_function(dev));
        pdev->vendor = pci_get_vendor(dev);
        pdev->device = pci_get_device(dev);
        pdev->subsystem_vendor = pci_get_subvendor(dev);
        pdev->subsystem_device = pci_get_subdevice(dev);
        pdev->class = pci_get_class(dev);
        pdev->revision = pci_get_revid(dev);
        pdev->path_name = kasprintf(GFP_KERNEL, "%04d:%02d:%02d.%d",
            pci_get_domain(dev), pci_get_bus(dev), pci_get_slot(dev),
            pci_get_function(dev));

        pdev->bus = malloc(sizeof(*pdev->bus), M_DEVBUF, M_WAITOK | M_ZERO);
        pdev->bus->number = pci_get_bus(dev);
        pdev->bus->domain = pci_get_domain(dev);

        /* Check if we have reached the root to satisfy pci_is_root_bus() */
        dinfo = device_get_ivars(dev);
        if (dinfo->cfg.pcie.pcie_location != 0 &&
            dinfo->cfg.pcie.pcie_type == PCIEM_TYPE_ROOT_PORT) {
                pdev->bus->self = NULL;
        } else {
                /*
                 * This should be the upstream bridge; pci_upstream_bridge()
                 * handles that case on demand as otherwise we'll shadow the
                 * entire PCI hierarchy.
                 */
                pdev->bus->self = pdev;
        }
        pdev->dev.bsddev = dev;
        pdev->dev.parent = &linux_root_device;
        pdev->dev.release = lkpi_pci_dev_release;

        if (pci_msi_count(dev) > 0)
                pdev->msi_desc = malloc(pci_msi_count(dev) *
                    sizeof(*pdev->msi_desc), M_DEVBUF, M_WAITOK | M_ZERO);

        TAILQ_INIT(&pdev->mmio);
        spin_lock_init(&pdev->pcie_cap_lock);
        spin_lock_init(&pdev->dev.devres_lock);
        INIT_LIST_HEAD(&pdev->dev.devres_head);
        INIT_LIST_HEAD(&pdev->dev.irqents);

        return (0);
}

static void
lkpinew_pci_dev_release(struct device *dev)
{
        struct pci_dev *pdev;
        int i;

        pdev = to_pci_dev(dev);
        if (pdev->root != NULL)
                pci_dev_put(pdev->root);
        if (pdev->bus->self != pdev && pdev->bus->self != NULL)
                pci_dev_put(pdev->bus->self);
        free(pdev->bus, M_DEVBUF);
        if (pdev->msi_desc != NULL) {
                for (i = pci_msi_count(pdev->dev.bsddev) - 1; i >= 0; i--)
                        free(pdev->msi_desc[i], M_DEVBUF);
                free(pdev->msi_desc, M_DEVBUF);
        }
        kfree(pdev->path_name);
        free(pdev, M_DEVBUF);
}

struct pci_dev *
lkpinew_pci_dev(device_t dev)
{
        struct pci_dev *pdev;
        int error;

        pdev = malloc(sizeof(*pdev), M_DEVBUF, M_WAITOK|M_ZERO);
        error = lkpifill_pci_dev(dev, pdev);
        if (error != 0) {
                free(pdev, M_DEVBUF);
                return (NULL);
        }
        pdev->dev.release = lkpinew_pci_dev_release;

        return (pdev);
}

struct pci_dev *
lkpi_pci_get_class(unsigned int class, struct pci_dev *from)
{
        device_t dev;
        device_t devfrom = NULL;
        struct pci_dev *pdev;

        if (from != NULL)
                devfrom = from->dev.bsddev;

        dev = pci_find_class_from(class >> 16, (class >> 8) & 0xFF, devfrom);
        if (dev == NULL)
                return (NULL);

        pdev = lkpinew_pci_dev(dev);
        return (pdev);
}

struct pci_dev *
lkpi_pci_get_base_class(unsigned int baseclass, struct pci_dev *from)
{
        device_t dev;
        device_t devfrom = NULL;
        struct pci_dev *pdev;

        if (from != NULL)
                devfrom = from->dev.bsddev;

        dev = pci_find_base_class_from(baseclass, devfrom);
        if (dev == NULL)
                return (NULL);

        pdev = lkpinew_pci_dev(dev);
        return (pdev);
}

struct pci_dev *
lkpi_pci_get_domain_bus_and_slot(int domain, unsigned int bus,
    unsigned int devfn)
{
        device_t dev;
        struct pci_dev *pdev;

        dev = pci_find_dbsf(domain, bus, PCI_SLOT(devfn), PCI_FUNC(devfn));
        if (dev == NULL)
                return (NULL);

        pdev = lkpinew_pci_dev(dev);
        return (pdev);
}

struct pci_dev *
lkpi_pci_get_slot(struct pci_bus *pbus, unsigned int devfn)
{
        device_t dev;
        struct pci_dev *pdev;

        dev = pci_find_bsf(pbus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
        if (dev == NULL)
                return (NULL);

        pdev = lkpinew_pci_dev(dev);
        return (pdev);
}

static int
linux_pci_probe(device_t dev)
{
        const struct pci_device_id *id;
        struct pci_driver *pdrv;

        if ((pdrv = linux_pci_find(dev, &id)) == NULL)
                return (ENXIO);
        if (device_get_driver(dev) != &pdrv->bsddriver)
                return (ENXIO);
        device_set_desc(dev, pdrv->name);

        /* Assume BSS initialized (should never return BUS_PROBE_SPECIFIC). */
        if (pdrv->bsd_probe_return == 0)
                return (BUS_PROBE_DEFAULT);
        else
                return (pdrv->bsd_probe_return);
}

static int
linux_pci_attach(device_t dev)
{
        const struct pci_device_id *id;
        struct pci_driver *pdrv;
        struct pci_dev *pdev;

        pdrv = linux_pci_find(dev, &id);
        pdev = device_get_softc(dev);

        MPASS(pdrv != NULL);
        MPASS(pdev != NULL);

        return (linux_pci_attach_device(dev, pdrv, id, pdev));
}

static struct resource_list_entry *
linux_pci_reserve_bar(struct pci_dev *pdev, struct resource_list *rl,
    int type, int rid)
{
        device_t dev;
        struct resource *res;

        KASSERT(type == SYS_RES_IOPORT || type == SYS_RES_MEMORY,
            ("trying to reserve non-BAR type %d", type));

        dev = pdev->pdrv != NULL && pdev->pdrv->isdrm ?
            device_get_parent(pdev->dev.bsddev) : pdev->dev.bsddev;
        res = pci_reserve_map(device_get_parent(dev), dev, type, rid, 0, ~0,
            1, 1, 0);
        if (res == NULL)
                return (NULL);
        return (resource_list_find(rl, type, rid));
}

static struct resource_list_entry *
linux_pci_get_rle(struct pci_dev *pdev, int type, int rid, bool reserve_bar)
{
        struct pci_devinfo *dinfo;
        struct resource_list *rl;
        struct resource_list_entry *rle;

        dinfo = device_get_ivars(pdev->dev.bsddev);
        rl = &dinfo->resources;
        rle = resource_list_find(rl, type, rid);
        /* Reserve resources for this BAR if needed. */
        if (rle == NULL && reserve_bar)
                rle = linux_pci_reserve_bar(pdev, rl, type, rid);
        return (rle);
}

int
linux_pci_attach_device(device_t dev, struct pci_driver *pdrv,
    const struct pci_device_id *id, struct pci_dev *pdev)
{
        struct resource_list_entry *rle;
        device_t parent;
        struct pci_dev *pbus, *ppbus;
        uintptr_t rid;
        int error;
        bool isdrm;

        linux_set_current(curthread);

        parent = device_get_parent(dev);
        isdrm = pdrv != NULL && pdrv->isdrm;

        if (isdrm) {
                struct pci_devinfo *dinfo;

                dinfo = device_get_ivars(parent);
                device_set_ivars(dev, dinfo);
        }

        error = lkpifill_pci_dev(dev, pdev);
        if (error != 0)
                return (error);

        if (isdrm)
                PCI_GET_ID(device_get_parent(parent), parent, PCI_ID_RID, &rid);
        else
                PCI_GET_ID(parent, dev, PCI_ID_RID, &rid);
        pdev->devfn = rid;
        pdev->pdrv = pdrv;
        rle = linux_pci_get_rle(pdev, SYS_RES_IRQ, 0, false);
        if (rle != NULL)
                pdev->dev.irq = rle->start;
        else
                pdev->dev.irq = LINUX_IRQ_INVALID;
        pdev->irq = pdev->dev.irq;
        error = linux_pdev_dma_init(pdev);
        if (error)
                goto out_dma_init;

        spin_lock(&pci_lock);
        list_add(&pdev->links, &pci_devices);
        spin_unlock(&pci_lock);

        /*
         * Create the hierarchy now as we cannot on demand later.
         * Take special care of DRM as there is a non-PCI device in the chain.
         */
        pbus = pdev;
        if (isdrm) {
                pbus = lkpinew_pci_dev(parent);
                if (pbus == NULL) {
                        error = ENXIO;
                        goto out_dma_init;
                }
        }
        pcie_find_root_port(pbus);
        if (isdrm)
                pdev->root = pbus->root;
        ppbus = pci_upstream_bridge(pbus);
        while (ppbus != NULL && ppbus != pbus) {
                pbus = ppbus;
                ppbus = pci_upstream_bridge(pbus);
        }

        if (pdrv != NULL) {
                error = pdrv->probe(pdev, id);
                if (error)
                        goto out_probe;
        }
        return (0);

/* XXX the cleanup does not match the allocation up there. */
out_probe:
        free(pdev->bus, M_DEVBUF);
        spin_lock_destroy(&pdev->pcie_cap_lock);
        linux_pdev_dma_uninit(pdev);
out_dma_init:
        spin_lock(&pci_lock);
        list_del(&pdev->links);
        spin_unlock(&pci_lock);
        put_device(&pdev->dev);
        return (-error);
}

static int
linux_pci_detach(device_t dev)
{
        struct pci_dev *pdev;

        pdev = device_get_softc(dev);

        MPASS(pdev != NULL);

        device_set_desc(dev, NULL);

        return (linux_pci_detach_device(pdev));
}

int
linux_pci_detach_device(struct pci_dev *pdev)
{

        linux_set_current(curthread);

        if (pdev->pdrv != NULL)
                pdev->pdrv->remove(pdev);

        if (pdev->root != NULL)
                pci_dev_put(pdev->root);
        free(pdev->bus, M_DEVBUF);
        linux_pdev_dma_uninit(pdev);

        spin_lock(&pci_lock);
        list_del(&pdev->links);
        spin_unlock(&pci_lock);
        spin_lock_destroy(&pdev->pcie_cap_lock);
        put_device(&pdev->dev);

        return (0);
}

static int
lkpi_pci_disable_dev(struct device *dev)
{

        (void) pci_disable_io(dev->bsddev, SYS_RES_MEMORY);
        (void) pci_disable_io(dev->bsddev, SYS_RES_IOPORT);
        return (0);
}

static struct pci_devres *
lkpi_pci_devres_get_alloc(struct pci_dev *pdev)
{
        struct pci_devres *dr;

        dr = lkpi_devres_find(&pdev->dev, lkpi_pci_devres_release, NULL, NULL);
        if (dr == NULL) {
                dr = lkpi_devres_alloc(lkpi_pci_devres_release, sizeof(*dr),
                    GFP_KERNEL | __GFP_ZERO);
                if (dr != NULL)
                        lkpi_devres_add(&pdev->dev, dr);
        }

        return (dr);
}

static struct pci_devres *
lkpi_pci_devres_find(struct pci_dev *pdev)
{
        if (!pdev->managed)
                return (NULL);

        return (lkpi_pci_devres_get_alloc(pdev));
}

void
lkpi_pci_devres_release(struct device *dev, void *p)
{
        struct pci_devres *dr;
        struct pci_dev *pdev;
        int bar;

        pdev = to_pci_dev(dev);
        dr = p;

        if (pdev->msix_enabled)
                lkpi_pci_disable_msix(pdev);
        if (pdev->msi_enabled)
                lkpi_pci_disable_msi(pdev);

        if (dr->enable_io && lkpi_pci_disable_dev(dev) == 0)
                dr->enable_io = false;

        if (dr->region_mask == 0)
                return;
        for (bar = PCIR_MAX_BAR_0; bar >= 0; bar--) {

                if ((dr->region_mask & (1 << bar)) == 0)
                        continue;
                pci_release_region(pdev, bar);
        }
}

int
linuxkpi_pcim_enable_device(struct pci_dev *pdev)
{
        struct pci_devres *dr;
        int error;

        /* Here we cannot run through the pdev->managed check. */
        dr = lkpi_pci_devres_get_alloc(pdev);
        if (dr == NULL)
                return (-ENOMEM);

        /* If resources were enabled before do not do it again. */
        if (dr->enable_io)
                return (0);

        error = pci_enable_device(pdev);
        if (error == 0)
                dr->enable_io = true;

        /* This device is not managed. */
        pdev->managed = true;

        return (error);
}

static struct pcim_iomap_devres *
lkpi_pcim_iomap_devres_find(struct pci_dev *pdev)
{
        struct pcim_iomap_devres *dr;

        dr = lkpi_devres_find(&pdev->dev, lkpi_pcim_iomap_table_release,
            NULL, NULL);
        if (dr == NULL) {
                dr = lkpi_devres_alloc(lkpi_pcim_iomap_table_release,
                    sizeof(*dr), GFP_KERNEL | __GFP_ZERO);
                if (dr != NULL)
                        lkpi_devres_add(&pdev->dev, dr);
        }

        if (dr == NULL)
                device_printf(pdev->dev.bsddev, "%s: NULL\n", __func__);

        return (dr);
}

void __iomem **
linuxkpi_pcim_iomap_table(struct pci_dev *pdev)
{
        struct pcim_iomap_devres *dr;

        dr = lkpi_pcim_iomap_devres_find(pdev);
        if (dr == NULL)
                return (NULL);

        /*
         * If the driver has manually set a flag to be able to request the
         * resource to use bus_read/write_<n>, return the shadow table.
         */
        if (pdev->want_iomap_res)
                return ((void **)dr->res_table);

        /* This is the Linux default. */
        return (dr->mmio_table);
}

static struct resource *
_lkpi_pci_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen __unused)
{
        struct pci_mmio_region *mmio, *p;
        int type;

        if (!lkpi_pci_bar_id_valid(bar))
                return (NULL);

        type = pci_resource_type(pdev, bar);
        if (type < 0) {
                device_printf(pdev->dev.bsddev, "%s: bar %d type %d\n",
                     __func__, bar, type);
                return (NULL);
        }

        /*
         * Check for duplicate mappings.
         * This can happen if a driver calls pci_request_region() first.
         */
        TAILQ_FOREACH_SAFE(mmio, &pdev->mmio, next, p) {
                if (mmio->type == type && mmio->rid == PCIR_BAR(bar)) {
                        return (mmio->res);
                }
        }

        mmio = malloc(sizeof(*mmio), M_DEVBUF, M_WAITOK | M_ZERO);
        mmio->rid = PCIR_BAR(bar);
        mmio->type = type;
        mmio->res = bus_alloc_resource_any(pdev->dev.bsddev, mmio->type,
            &mmio->rid, RF_ACTIVE|RF_SHAREABLE);
        if (mmio->res == NULL) {
                device_printf(pdev->dev.bsddev, "%s: failed to alloc "
                    "bar %d type %d rid %d\n",
                    __func__, bar, type, PCIR_BAR(bar));
                free(mmio, M_DEVBUF);
                return (NULL);
        }
        TAILQ_INSERT_TAIL(&pdev->mmio, mmio, next);

        return (mmio->res);
}

void *
linuxkpi_pci_iomap_range(struct pci_dev *pdev, int bar,
    unsigned long off, unsigned long maxlen)
{
        struct resource *res;

        if (!lkpi_pci_bar_id_valid(bar))
                return (NULL);

        res = _lkpi_pci_iomap(pdev, bar, maxlen);
        if (res == NULL)
                return (NULL);
        /* This is a FreeBSD extension so we can use bus_*(). */
        if (pdev->want_iomap_res)
                return (res);
        MPASS(off < rman_get_size(res));
        return ((void *)(rman_get_bushandle(res) + off));
}

void *
linuxkpi_pci_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
{
        if (!lkpi_pci_bar_id_valid(bar))
                return (NULL);

        return (linuxkpi_pci_iomap_range(pdev, bar, 0, maxlen));
}

void *
linuxkpi_pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen)
{
        struct pcim_iomap_devres *dr;
        void *res;

        if (!lkpi_pci_bar_id_valid(bar))
                return (NULL);

        dr = lkpi_pcim_iomap_devres_find(pdev);
        if (dr == NULL)
                return (NULL);

        if (dr->res_table[bar] != NULL)
                return (dr->res_table[bar]);

        res = linuxkpi_pci_iomap(pdev, bar, maxlen);
        if (res == NULL) {
                /*
                 * Do not free the devres in case there were
                 * other valid mappings before already.
                 */
                return (NULL);
        }
        lkpi_set_pcim_iomap_devres(dr, bar, res);

        return (res);
}

void
linuxkpi_pci_iounmap(struct pci_dev *pdev, void *res)
{
        struct pci_mmio_region *mmio, *p;
        bus_space_handle_t bh = (bus_space_handle_t)res;

        TAILQ_FOREACH_SAFE(mmio, &pdev->mmio, next, p) {
                if (pdev->want_iomap_res) {
                        if (res != mmio->res)
                                continue;
                } else {
                        if (bh <  rman_get_bushandle(mmio->res) ||
                            bh >= rman_get_bushandle(mmio->res) +
                                  rman_get_size(mmio->res))
                                continue;
                }
                bus_release_resource(pdev->dev.bsddev,
                    mmio->type, mmio->rid, mmio->res);
                TAILQ_REMOVE(&pdev->mmio, mmio, next);
                free(mmio, M_DEVBUF);
                return;
        }
}

int
linuxkpi_pcim_iomap_regions(struct pci_dev *pdev, uint32_t mask, const char *name)
{
        struct pcim_iomap_devres *dr;
        void *res;
        uint32_t mappings;
        int bar;

        dr = lkpi_pcim_iomap_devres_find(pdev);
        if (dr == NULL)
                return (-ENOMEM);

        /* Now iomap all the requested (by "mask") ones. */
        for (bar = mappings = 0; mappings != mask; bar++) {
                if ((mask & (1 << bar)) == 0)
                        continue;

                /* Request double is not allowed. */
                if (dr->mmio_table[bar] != NULL) {
                        device_printf(pdev->dev.bsddev, "%s: bar %d %p\n",
                            __func__, bar, dr->mmio_table[bar]);
                        goto err;
                }

                res = _lkpi_pci_iomap(pdev, bar, 0);
                if (res == NULL)
                        goto err;
                lkpi_set_pcim_iomap_devres(dr, bar, res);

                mappings |= (1 << bar);
        }

        return (0);
err:
        for (bar = PCIR_MAX_BAR_0; bar >= 0; bar--) {
                if ((mappings & (1 << bar)) != 0) {
                        res = dr->mmio_table[bar];
                        if (res == NULL)
                                continue;
                        pci_iounmap(pdev, res);
                }
        }

        return (-EINVAL);
}

static void
lkpi_pcim_iomap_table_release(struct device *dev, void *p)
{
        struct pcim_iomap_devres *dr;
        struct pci_dev *pdev;
        int bar;

        dr = p;
        pdev = to_pci_dev(dev);
        for (bar = PCIR_MAX_BAR_0; bar >= 0; bar--) {

                if (dr->mmio_table[bar] == NULL)
                        continue;

                pci_iounmap(pdev, dr->mmio_table[bar]);
        }
}

static int
linux_pci_suspend(device_t dev)
{
        const struct dev_pm_ops *pmops;
        struct pm_message pm = { };
        struct pci_dev *pdev;
        int error;

        error = 0;
        linux_set_current(curthread);
        pdev = device_get_softc(dev);
        pmops = pdev->pdrv->driver.pm;

        if (pdev->pdrv->suspend != NULL)
                error = -pdev->pdrv->suspend(pdev, pm);
        else if (pmops != NULL && pmops->suspend != NULL) {
                error = -pmops->suspend(&pdev->dev);
                if (error == 0 && pmops->suspend_late != NULL)
                        error = -pmops->suspend_late(&pdev->dev);
                if (error == 0 && pmops->suspend_noirq != NULL)
                        error = -pmops->suspend_noirq(&pdev->dev);
        }
        return (error);
}

static int
linux_pci_resume(device_t dev)
{
        const struct dev_pm_ops *pmops;
        struct pci_dev *pdev;
        int error;

        error = 0;
        linux_set_current(curthread);
        pdev = device_get_softc(dev);
        pmops = pdev->pdrv->driver.pm;

        if (pdev->pdrv->resume != NULL)
                error = -pdev->pdrv->resume(pdev);
        else if (pmops != NULL && pmops->resume != NULL) {
                if (pmops->resume_early != NULL)
                        error = -pmops->resume_early(&pdev->dev);
                if (error == 0 && pmops->resume != NULL)
                        error = -pmops->resume(&pdev->dev);
        }
        return (error);
}

static int
linux_pci_shutdown(device_t dev)
{
        struct pci_dev *pdev;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);
        if (pdev->pdrv->shutdown != NULL)
                pdev->pdrv->shutdown(pdev);
        return (0);
}

static int
linux_pci_iov_init(device_t dev, uint16_t num_vfs, const nvlist_t *pf_config)
{
        struct pci_dev *pdev;
        int error;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);
        if (pdev->pdrv->bsd_iov_init != NULL)
                error = pdev->pdrv->bsd_iov_init(dev, num_vfs, pf_config);
        else
                error = EINVAL;
        return (error);
}

static void
linux_pci_iov_uninit(device_t dev)
{
        struct pci_dev *pdev;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);
        if (pdev->pdrv->bsd_iov_uninit != NULL)
                pdev->pdrv->bsd_iov_uninit(dev);
}

static int
linux_pci_iov_add_vf(device_t dev, uint16_t vfnum, const nvlist_t *vf_config)
{
        struct pci_dev *pdev;
        int error;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);
        if (pdev->pdrv->bsd_iov_add_vf != NULL)
                error = pdev->pdrv->bsd_iov_add_vf(dev, vfnum, vf_config);
        else
                error = EINVAL;
        return (error);
}

static int
_linux_pci_register_driver(struct pci_driver *pdrv, devclass_t dc)
{
        int error;

        linux_set_current(curthread);
        spin_lock(&pci_lock);
        list_add(&pdrv->node, &pci_drivers);
        spin_unlock(&pci_lock);
        if (pdrv->bsddriver.name == NULL)
                pdrv->bsddriver.name = pdrv->name;
        pdrv->bsddriver.methods = pci_methods;
        pdrv->bsddriver.size = sizeof(struct pci_dev);

        bus_topo_lock();
        error = devclass_add_driver(dc, &pdrv->bsddriver,
            BUS_PASS_DEFAULT, &pdrv->bsdclass);
        bus_topo_unlock();
        return (-error);
}

int
linux_pci_register_driver(struct pci_driver *pdrv)
{
        devclass_t dc;

        pdrv->isdrm = strcmp(pdrv->name, "drmn") == 0;
        dc = pdrv->isdrm ? devclass_create("vgapci") : devclass_find("pci");
        if (dc == NULL)
                return (-ENXIO);
        return (_linux_pci_register_driver(pdrv, dc));
}

static struct resource_list_entry *
lkpi_pci_get_bar(struct pci_dev *pdev, int bar, bool reserve)
{
        int type;

        type = pci_resource_type(pdev, bar);
        if (type < 0)
                return (NULL);
        bar = PCIR_BAR(bar);
        return (linux_pci_get_rle(pdev, type, bar, reserve));
}

struct device *
lkpi_pci_find_irq_dev(unsigned int irq)
{
        struct pci_dev *pdev;
        struct device *found;

        found = NULL;
        spin_lock(&pci_lock);
        list_for_each_entry(pdev, &pci_devices, links) {
                if (irq == pdev->dev.irq ||
                    (irq >= pdev->dev.irq_start && irq < pdev->dev.irq_end)) {
                        found = &pdev->dev;
                        break;
                }
        }
        spin_unlock(&pci_lock);
        return (found);
}

unsigned long
pci_resource_start(struct pci_dev *pdev, int bar)
{
        struct resource_list_entry *rle;
        rman_res_t newstart;
        device_t dev;
        int error;

        if ((rle = lkpi_pci_get_bar(pdev, bar, true)) == NULL)
                return (0);
        dev = pdev->pdrv != NULL && pdev->pdrv->isdrm ?
            device_get_parent(pdev->dev.bsddev) : pdev->dev.bsddev;
        error = bus_translate_resource(dev, rle->type, rle->start, &newstart);
        if (error != 0) {
                device_printf(pdev->dev.bsddev,
                    "translate of %#jx failed: %d\n",
                    (uintmax_t)rle->start, error);
                return (0);
        }
        return (newstart);
}

unsigned long
pci_resource_len(struct pci_dev *pdev, int bar)
{
        struct resource_list_entry *rle;

        if ((rle = lkpi_pci_get_bar(pdev, bar, true)) == NULL)
                return (0);
        return (rle->count);
}

static int
lkpi_pci_request_region(struct pci_dev *pdev, int bar, const char *res_name,
    bool managed)
{
        struct resource *res;
        struct pci_devres *dr;
        struct pci_mmio_region *mmio;
        int rid;
        int type;

        if (!lkpi_pci_bar_id_valid(bar))
                return (-EINVAL);

        type = pci_resource_type(pdev, bar);
        if (type < 0)
                return (0);

        rid = PCIR_BAR(bar);
        res = bus_alloc_resource_any(pdev->dev.bsddev, type, &rid,
            RF_ACTIVE|RF_SHAREABLE);
        if (res == NULL) {
                device_printf(pdev->dev.bsddev, "%s: failed to alloc "
                    "bar %d type %d rid %d\n",
                    __func__, bar, type, PCIR_BAR(bar));
                return (-EBUSY);
        }

        /*
         * It seems there is an implicit devres tracking on these if the device
         * is managed (lkpi_pci_devres_find() case); otherwise the resources are
         * not automatically freed on FreeBSD/LinuxKPI though they should be/are
         * expected to be by Linux drivers.
         * Otherwise if we are called from a pcim-function with the managed
         * argument set, we need to track devres independent of pdev->managed.
         */
        if (managed)
                dr = lkpi_pci_devres_get_alloc(pdev);
        else
                dr = lkpi_pci_devres_find(pdev);
        if (dr != NULL) {
                dr->region_mask |= (1 << bar);
                dr->region_table[bar] = res;
        }

        /* Even if the device is not managed we need to track it for iomap. */
        mmio = malloc(sizeof(*mmio), M_DEVBUF, M_WAITOK | M_ZERO);
        mmio->rid = PCIR_BAR(bar);
        mmio->type = type;
        mmio->res = res;
        TAILQ_INSERT_TAIL(&pdev->mmio, mmio, next);

        return (0);
}

int
linuxkpi_pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
{
        return (lkpi_pci_request_region(pdev, bar, res_name, false));
}

int
linuxkpi_pci_request_regions(struct pci_dev *pdev, const char *res_name)
{
        int error;
        int i;

        for (i = 0; i <= PCIR_MAX_BAR_0; i++) {
                error = pci_request_region(pdev, i, res_name);
                if (error && error != -EBUSY) {
                        pci_release_regions(pdev);
                        return (error);
                }
        }
        return (0);
}

int
linuxkpi_pcim_request_all_regions(struct pci_dev *pdev, const char *res_name)
{
        int bar, error;

        for (bar = 0; bar <= PCIR_MAX_BAR_0; bar++) {
                error = lkpi_pci_request_region(pdev, bar, res_name, true);
                if (error != 0 && error != -EBUSY) {
                        device_printf(pdev->dev.bsddev, "%s: bar %d res_name '%s': "
                            "lkpi_pci_request_region returned %d\n", __func__,
                            bar, res_name, error);
                        pci_release_regions(pdev);
                        return (error);
                }
        }
        return (0);
}

void
linuxkpi_pci_release_region(struct pci_dev *pdev, int bar)
{
        struct resource_list_entry *rle;
        struct pci_devres *dr;
        struct pci_mmio_region *mmio, *p;

        if ((rle = lkpi_pci_get_bar(pdev, bar, false)) == NULL)
                return;

        /*
         * As we implicitly track the requests we also need to clear them on
         * release.  Do clear before resource release.
         */
        dr = lkpi_pci_devres_find(pdev);
        if (dr != NULL) {
                KASSERT(dr->region_table[bar] == rle->res, ("%s: pdev %p bar %d"
                    " region_table res %p != rel->res %p\n", __func__, pdev,
                    bar, dr->region_table[bar], rle->res));
                dr->region_table[bar] = NULL;
                dr->region_mask &= ~(1 << bar);
        }

        TAILQ_FOREACH_SAFE(mmio, &pdev->mmio, next, p) {
                if (rle->res != (void *)rman_get_bushandle(mmio->res))
                        continue;
                TAILQ_REMOVE(&pdev->mmio, mmio, next);
                free(mmio, M_DEVBUF);
        }

        bus_release_resource(pdev->dev.bsddev, rle->type, rle->rid, rle->res);
}

void
linuxkpi_pci_release_regions(struct pci_dev *pdev)
{
        int i;

        for (i = 0; i <= PCIR_MAX_BAR_0; i++)
                pci_release_region(pdev, i);
}

int
linux_pci_register_drm_driver(struct pci_driver *pdrv)
{
        devclass_t dc;

        dc = devclass_create("vgapci");
        if (dc == NULL)
                return (-ENXIO);
        pdrv->isdrm = true;
        pdrv->name = "drmn";
        return (_linux_pci_register_driver(pdrv, dc));
}

void
linux_pci_unregister_driver(struct pci_driver *pdrv)
{
        devclass_t bus;

        bus = devclass_find(pdrv->isdrm ? "vgapci" : "pci");

        spin_lock(&pci_lock);
        list_del(&pdrv->node);
        spin_unlock(&pci_lock);
        bus_topo_lock();
        if (bus != NULL)
                devclass_delete_driver(bus, &pdrv->bsddriver);
        bus_topo_unlock();
}

void
linux_pci_unregister_drm_driver(struct pci_driver *pdrv)
{
        devclass_t bus;

        bus = devclass_find("vgapci");

        spin_lock(&pci_lock);
        list_del(&pdrv->node);
        spin_unlock(&pci_lock);
        bus_topo_lock();
        if (bus != NULL)
                devclass_delete_driver(bus, &pdrv->bsddriver);
        bus_topo_unlock();
}

int
linuxkpi_pci_enable_msix(struct pci_dev *pdev, struct msix_entry *entries,
    int nreq)
{
        struct resource_list_entry *rle;
        int error;
        int avail;
        int i;

        avail = pci_msix_count(pdev->dev.bsddev);
        if (avail < nreq) {
                if (avail == 0)
                        return -EINVAL;
                return avail;
        }
        avail = nreq;
        if ((error = -pci_alloc_msix(pdev->dev.bsddev, &avail)) != 0)
                return error;
        /*
        * Handle case where "pci_alloc_msix()" may allocate less
        * interrupts than available and return with no error:
        */
        if (avail < nreq) {
                pci_release_msi(pdev->dev.bsddev);
                return avail;
        }
        rle = linux_pci_get_rle(pdev, SYS_RES_IRQ, 1, false);
        pdev->dev.irq_start = rle->start;
        pdev->dev.irq_end = rle->start + avail;
        for (i = 0; i < nreq; i++)
                entries[i].vector = pdev->dev.irq_start + i;
        pdev->msix_enabled = true;
        return (0);
}

int
_lkpi_pci_enable_msi_range(struct pci_dev *pdev, int minvec, int maxvec)
{
        struct resource_list_entry *rle;
        int error;
        int nvec;

        if (maxvec < minvec)
                return (-EINVAL);

        nvec = pci_msi_count(pdev->dev.bsddev);
        if (nvec < 1 || nvec < minvec)
                return (-ENOSPC);

        nvec = min(nvec, maxvec);
        if ((error = -pci_alloc_msi(pdev->dev.bsddev, &nvec)) != 0)
                return error;

        /* Native PCI might only ever ask for 32 vectors. */
        if (nvec < minvec) {
                pci_release_msi(pdev->dev.bsddev);
                return (-ENOSPC);
        }

        rle = linux_pci_get_rle(pdev, SYS_RES_IRQ, 1, false);
        pdev->dev.irq_start = rle->start;
        pdev->dev.irq_end = rle->start + nvec;
        pdev->irq = rle->start;
        pdev->msi_enabled = true;
        return (0);
}

int
pci_alloc_irq_vectors(struct pci_dev *pdev, int minv, int maxv,
    unsigned int flags)
{
        int error;

        if (flags & PCI_IRQ_MSIX) {
                struct msix_entry *entries;
                int i;

                entries = kcalloc(maxv, sizeof(*entries), GFP_KERNEL);
                if (entries == NULL) {
                        error = -ENOMEM;
                        goto out;
                }
                for (i = 0; i < maxv; ++i)
                        entries[i].entry = i;
                error = pci_enable_msix(pdev, entries, maxv);
out:
                kfree(entries);
                if (error == 0 && pdev->msix_enabled)
                        return (pdev->dev.irq_end - pdev->dev.irq_start);
        }
        if (flags & PCI_IRQ_MSI) {
                if (pci_msi_count(pdev->dev.bsddev) < minv)
                        return (-ENOSPC);
                error = _lkpi_pci_enable_msi_range(pdev, minv, maxv);
                if (error == 0 && pdev->msi_enabled)
                        return (pdev->dev.irq_end - pdev->dev.irq_start);
        }
        if (flags & PCI_IRQ_INTX) {
                if (pdev->irq)
                        return (1);
        }

        return (-EINVAL);
}

struct msi_desc *
lkpi_pci_msi_desc_alloc(int irq)
{
        struct device *dev;
        struct pci_dev *pdev;
        struct msi_desc *desc;
        struct pci_devinfo *dinfo;
        struct pcicfg_msi *msi;
        int vec;

        dev = lkpi_pci_find_irq_dev(irq);
        if (dev == NULL)
                return (NULL);

        pdev = to_pci_dev(dev);

        if (pdev->msi_desc == NULL)
                return (NULL);

        if (irq < pdev->dev.irq_start || irq >= pdev->dev.irq_end)
                return (NULL);

        vec = pdev->dev.irq_start - irq;

        if (pdev->msi_desc[vec] != NULL)
                return (pdev->msi_desc[vec]);

        dinfo = device_get_ivars(dev->bsddev);
        msi = &dinfo->cfg.msi;

        desc = malloc(sizeof(*desc), M_DEVBUF, M_WAITOK | M_ZERO);

        desc->pci.msi_attrib.is_64 =
           (msi->msi_ctrl & PCIM_MSICTRL_64BIT) ? true : false;
        desc->msg.data = msi->msi_data;

        pdev->msi_desc[vec] = desc;

        return (desc);
}

bool
pci_device_is_present(struct pci_dev *pdev)
{
        device_t dev;

        dev = pdev->dev.bsddev;

        return (bus_child_present(dev));
}

CTASSERT(sizeof(dma_addr_t) <= sizeof(uint64_t));

struct linux_dma_obj {
        void            *vaddr;
        uint64_t        dma_addr;
        bus_dmamap_t    dmamap;
        bus_dma_tag_t   dmat;
};

static uma_zone_t linux_dma_trie_zone;
static uma_zone_t linux_dma_obj_zone;

static void
linux_dma_init(void *arg)
{

        linux_dma_trie_zone = uma_zcreate("linux_dma_pctrie",
            pctrie_node_size(), NULL, NULL, pctrie_zone_init, NULL,
            UMA_ALIGN_PTR, 0);
        linux_dma_obj_zone = uma_zcreate("linux_dma_object",
            sizeof(struct linux_dma_obj), NULL, NULL, NULL, NULL,
            UMA_ALIGN_PTR, 0);
        lkpi_pci_nseg1_fail = counter_u64_alloc(M_WAITOK);
}
SYSINIT(linux_dma, SI_SUB_DRIVERS, SI_ORDER_THIRD, linux_dma_init, NULL);

static void
linux_dma_uninit(void *arg)
{

        counter_u64_free(lkpi_pci_nseg1_fail);
        uma_zdestroy(linux_dma_obj_zone);
        uma_zdestroy(linux_dma_trie_zone);
}
SYSUNINIT(linux_dma, SI_SUB_DRIVERS, SI_ORDER_THIRD, linux_dma_uninit, NULL);

static void *
linux_dma_trie_alloc(struct pctrie *ptree)
{

        return (uma_zalloc(linux_dma_trie_zone, M_NOWAIT));
}

static void
linux_dma_trie_free(struct pctrie *ptree, void *node)
{

        uma_zfree(linux_dma_trie_zone, node);
}

PCTRIE_DEFINE(LINUX_DMA, linux_dma_obj, dma_addr, linux_dma_trie_alloc,
    linux_dma_trie_free);

#if defined(__i386__) || defined(__amd64__) || defined(__aarch64__)
static dma_addr_t
linux_dma_map_phys_common(struct device *dev, vm_paddr_t phys, size_t len,
    bus_dma_tag_t dmat)
{
        struct linux_dma_priv *priv;
        struct linux_dma_obj *obj;
        int error, nseg;
        bus_dma_segment_t seg;

        priv = dev->dma_priv;

        /*
         * If the resultant mapping will be entirely 1:1 with the
         * physical address, short-circuit the remainder of the
         * bus_dma API.  This avoids tracking collisions in the pctrie
         * with the additional benefit of reducing overhead.
         */
        if (bus_dma_id_mapped(dmat, phys, len))
                return (phys);

        obj = uma_zalloc(linux_dma_obj_zone, M_NOWAIT);
        if (obj == NULL) {
                return (0);
        }
        obj->dmat = dmat;

        DMA_PRIV_LOCK(priv);
        if (bus_dmamap_create(obj->dmat, 0, &obj->dmamap) != 0) {
                DMA_PRIV_UNLOCK(priv);
                uma_zfree(linux_dma_obj_zone, obj);
                return (0);
        }

        nseg = -1;
        error = _bus_dmamap_load_phys(obj->dmat, obj->dmamap, phys, len,
            BUS_DMA_NOWAIT, &seg, &nseg);
        if (error != 0) {
                bus_dmamap_destroy(obj->dmat, obj->dmamap);
                DMA_PRIV_UNLOCK(priv);
                uma_zfree(linux_dma_obj_zone, obj);
                counter_u64_add(lkpi_pci_nseg1_fail, 1);
                if (linuxkpi_debug) {
                        device_printf(dev->bsddev, "%s: _bus_dmamap_load_phys "
                            "error %d, phys %#018jx len %zu\n", __func__,
                            error, (uintmax_t)phys, len);
                        dump_stack();
                }
                return (0);
        }

        KASSERT(++nseg == 1, ("More than one segment (nseg=%d)", nseg));
        obj->dma_addr = seg.ds_addr;

        error = LINUX_DMA_PCTRIE_INSERT(&priv->ptree, obj);
        if (error != 0) {
                bus_dmamap_unload(obj->dmat, obj->dmamap);
                bus_dmamap_destroy(obj->dmat, obj->dmamap);
                DMA_PRIV_UNLOCK(priv);
                uma_zfree(linux_dma_obj_zone, obj);
                return (0);
        }
        DMA_PRIV_UNLOCK(priv);
        return (obj->dma_addr);
}
#else
static dma_addr_t
linux_dma_map_phys_common(struct device *dev __unused, vm_paddr_t phys,
    size_t len __unused, bus_dma_tag_t dmat __unused)
{
        return (phys);
}
#endif

dma_addr_t
lkpi_dma_map_phys(struct device *dev, vm_paddr_t phys, size_t len,
    enum dma_data_direction direction, unsigned long attrs)
{
        struct linux_dma_priv *priv;
        dma_addr_t dma;

        priv = dev->dma_priv;
        dma = linux_dma_map_phys_common(dev, phys, len, priv->dmat);
        if (dma_mapping_error(dev, dma))
                return (dma);

        if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
                dma_sync_single_for_device(dev, dma, len, direction);

        return (dma);
}

/* For backward compat only so we can MFC this. Remove before 15. */
dma_addr_t
linux_dma_map_phys(struct device *dev, vm_paddr_t phys, size_t len)
{
        return (lkpi_dma_map_phys(dev, phys, len, DMA_NONE, 0));
}

#if defined(__i386__) || defined(__amd64__) || defined(__aarch64__)
void
lkpi_dma_unmap(struct device *dev, dma_addr_t dma_addr, size_t len,
    enum dma_data_direction direction, unsigned long attrs)
{
        struct linux_dma_priv *priv;
        struct linux_dma_obj *obj;

        priv = dev->dma_priv;

        if (pctrie_is_empty(&priv->ptree))
                return;

        DMA_PRIV_LOCK(priv);
        obj = LINUX_DMA_PCTRIE_LOOKUP(&priv->ptree, dma_addr);
        if (obj == NULL) {
                DMA_PRIV_UNLOCK(priv);
                return;
        }
        LINUX_DMA_PCTRIE_REMOVE(&priv->ptree, dma_addr);

        if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) != 0)
                goto skip_sync;

        /* dma_sync_single_for_cpu() unrolled to avoid lock recursicn. */
        switch (direction) {
        case DMA_BIDIRECTIONAL:
                bus_dmamap_sync(obj->dmat, obj->dmamap, BUS_DMASYNC_POSTREAD);
                bus_dmamap_sync(obj->dmat, obj->dmamap, BUS_DMASYNC_PREREAD);
                break;
        case DMA_TO_DEVICE:
                bus_dmamap_sync(obj->dmat, obj->dmamap, BUS_DMASYNC_POSTWRITE);
                break;
        case DMA_FROM_DEVICE:
                bus_dmamap_sync(obj->dmat, obj->dmamap, BUS_DMASYNC_POSTREAD);
                break;
        default:
                break;
        }

skip_sync:
        bus_dmamap_unload(obj->dmat, obj->dmamap);
        bus_dmamap_destroy(obj->dmat, obj->dmamap);
        DMA_PRIV_UNLOCK(priv);

        uma_zfree(linux_dma_obj_zone, obj);
}
#else
void
lkpi_dma_unmap(struct device *dev, dma_addr_t dma_addr, size_t len,
    enum dma_data_direction direction, unsigned long attrs)
{
}
#endif

/* For backward compat only so we can MFC this. Remove before 15. */
void
linux_dma_unmap(struct device *dev, dma_addr_t dma_addr, size_t len)
{
        lkpi_dma_unmap(dev, dma_addr, len, DMA_NONE, 0);
}

void *
linux_dma_alloc_coherent(struct device *dev, size_t size,
    dma_addr_t *dma_handle, gfp_t flag)
{
        struct linux_dma_priv *priv;
        vm_paddr_t high;
        size_t align;
        void *mem;

        if (dev == NULL || dev->dma_priv == NULL) {
                *dma_handle = 0;
                return (NULL);
        }
        priv = dev->dma_priv;
        if (priv->dma_coherent_mask)
                high = priv->dma_coherent_mask;
        else
                /* Coherent is lower 32bit only by default in Linux. */
                high = BUS_SPACE_MAXADDR_32BIT;
        align = PAGE_SIZE << get_order(size);
        /* Always zero the allocation. */
        flag |= M_ZERO;
        mem = kmem_alloc_contig(size, flag & GFP_NATIVE_MASK, 0, high,
            align, 0, VM_MEMATTR_DEFAULT);
        if (mem != NULL) {
                *dma_handle = linux_dma_map_phys_common(dev, vtophys(mem), size,
                    priv->dmat_coherent);
                if (*dma_handle == 0) {
                        kmem_free(mem, size);
                        mem = NULL;
                }
        } else {
                *dma_handle = 0;
        }
        return (mem);
}

struct lkpi_devres_dmam_coherent {
        size_t size;
        dma_addr_t *handle;
        void *mem;
};

static void
lkpi_dmam_free_coherent(struct device *dev, void *p)
{
        struct lkpi_devres_dmam_coherent *dr;

        dr = p;
        dma_free_coherent(dev, dr->size, dr->mem, *dr->handle);
}

static int
lkpi_dmam_coherent_match(struct device *dev, void *dr, void *mp)
{
        struct lkpi_devres_dmam_coherent *a, *b;

        a = dr;
        b = mp;

        if (a->mem != b->mem)
                return (0);
        if (a->size != b->size || a->handle != b->handle)
                dev_WARN(dev, "for mem %p: size %zu != %zu || handle %#jx != %#jx\n",
                    a->mem, a->size, b->size,
                    (uintmax_t)a->handle, (uintmax_t)b->handle);
        return (1);
}

void
linuxkpi_dmam_free_coherent(struct device *dev, size_t size,
    void *addr, dma_addr_t dma_handle)
{
        struct lkpi_devres_dmam_coherent match = {
                .size           = size,
                .handle         = &dma_handle,
                .mem            = addr
        };
        int error;

        error = devres_destroy(dev, lkpi_dmam_free_coherent,
            lkpi_dmam_coherent_match, &match);
        if (error != 0)
                dev_WARN(dev, "devres_destroy returned %d, size %zu addr %p "
                    "dma_handle %#jx\n", error, size, addr, (uintmax_t)dma_handle);
        dma_free_coherent(dev, size, addr, dma_handle);
}

void *
linuxkpi_dmam_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
    gfp_t flag)
{
        struct lkpi_devres_dmam_coherent *dr;

        dr = lkpi_devres_alloc(lkpi_dmam_free_coherent,
            sizeof(*dr), GFP_KERNEL | __GFP_ZERO);

        if (dr == NULL)
                return (NULL);

        dr->size = size;
        dr->mem = linux_dma_alloc_coherent(dev, size, dma_handle, flag);
        dr->handle = dma_handle;
        if (dr->mem == NULL) {
                lkpi_devres_free(dr);
                return (NULL);
        }

        lkpi_devres_add(dev, dr);
        return (dr->mem);
}

void
linuxkpi_dma_sync(struct device *dev, dma_addr_t dma_addr, size_t size,
    bus_dmasync_op_t op)
{
        struct linux_dma_priv *priv;
        struct linux_dma_obj *obj;

        priv = dev->dma_priv;

        if (pctrie_is_empty(&priv->ptree))
                return;

        DMA_PRIV_LOCK(priv);
        obj = LINUX_DMA_PCTRIE_LOOKUP(&priv->ptree, dma_addr);
        if (obj == NULL) {
                DMA_PRIV_UNLOCK(priv);
                return;
        }

        bus_dmamap_sync(obj->dmat, obj->dmamap, op);
        DMA_PRIV_UNLOCK(priv);
}

int
linux_dma_map_sg_attrs(struct device *dev, struct scatterlist *sgl, int nents,
    enum dma_data_direction direction, unsigned long attrs)
{
        struct linux_dma_priv *priv;
        struct scatterlist *sg;
        int i, nseg;
        bus_dma_segment_t seg;

        priv = dev->dma_priv;

        DMA_PRIV_LOCK(priv);

        /* create common DMA map in the first S/G entry */
        if (bus_dmamap_create(priv->dmat, 0, &sgl->dma_map) != 0) {
                DMA_PRIV_UNLOCK(priv);
                return (0);
        }

        /* load all S/G list entries */
        for_each_sg(sgl, sg, nents, i) {
                nseg = -1;
                if (_bus_dmamap_load_phys(priv->dmat, sgl->dma_map,
                    sg_phys(sg), sg->length, BUS_DMA_NOWAIT,
                    &seg, &nseg) != 0) {
                        bus_dmamap_unload(priv->dmat, sgl->dma_map);
                        bus_dmamap_destroy(priv->dmat, sgl->dma_map);
                        DMA_PRIV_UNLOCK(priv);
                        return (0);
                }
                KASSERT(nseg == 0,
                    ("More than one segment (nseg=%d)", nseg + 1));

                sg_dma_address(sg) = seg.ds_addr;
        }

        if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) != 0)
                goto skip_sync;

        switch (direction) {
        case DMA_BIDIRECTIONAL:
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_PREWRITE);
                break;
        case DMA_TO_DEVICE:
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_PREREAD);
                break;
        case DMA_FROM_DEVICE:
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_PREWRITE);
                break;
        default:
                break;
        }
skip_sync:

        DMA_PRIV_UNLOCK(priv);

        return (nents);
}

void
linux_dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sgl,
    int nents __unused, enum dma_data_direction direction,
    unsigned long attrs)
{
        struct linux_dma_priv *priv;

        priv = dev->dma_priv;

        DMA_PRIV_LOCK(priv);

        if ((attrs & DMA_ATTR_SKIP_CPU_SYNC) != 0)
                goto skip_sync;

        switch (direction) {
        case DMA_BIDIRECTIONAL:
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_POSTREAD);
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_PREREAD);
                break;
        case DMA_TO_DEVICE:
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_POSTWRITE);
                break;
        case DMA_FROM_DEVICE:
                bus_dmamap_sync(priv->dmat, sgl->dma_map, BUS_DMASYNC_POSTREAD);
                break;
        default:
                break;
        }
skip_sync:

        bus_dmamap_unload(priv->dmat, sgl->dma_map);
        bus_dmamap_destroy(priv->dmat, sgl->dma_map);
        DMA_PRIV_UNLOCK(priv);
}

struct dma_pool {
        struct device  *pool_device;
        uma_zone_t      pool_zone;
        struct mtx      pool_lock;
        bus_dma_tag_t   pool_dmat;
        size_t          pool_entry_size;
        struct pctrie   pool_ptree;
};

#define DMA_POOL_LOCK(pool) mtx_lock(&(pool)->pool_lock)
#define DMA_POOL_UNLOCK(pool) mtx_unlock(&(pool)->pool_lock)

static inline int
dma_pool_obj_ctor(void *mem, int size, void *arg, int flags)
{
        struct linux_dma_obj *obj = mem;
        struct dma_pool *pool = arg;
        int error, nseg;
        bus_dma_segment_t seg;

        nseg = -1;
        DMA_POOL_LOCK(pool);
        error = _bus_dmamap_load_phys(pool->pool_dmat, obj->dmamap,
            vtophys(obj->vaddr), pool->pool_entry_size, BUS_DMA_NOWAIT,
            &seg, &nseg);
        DMA_POOL_UNLOCK(pool);
        if (error != 0) {
                return (error);
        }
        KASSERT(++nseg == 1, ("More than one segment (nseg=%d)", nseg));
        obj->dma_addr = seg.ds_addr;

        return (0);
}

static void
dma_pool_obj_dtor(void *mem, int size, void *arg)
{
        struct linux_dma_obj *obj = mem;
        struct dma_pool *pool = arg;

        DMA_POOL_LOCK(pool);
        bus_dmamap_unload(pool->pool_dmat, obj->dmamap);
        DMA_POOL_UNLOCK(pool);
}

static int
dma_pool_obj_import(void *arg, void **store, int count, int domain __unused,
    int flags)
{
        struct dma_pool *pool = arg;
        struct linux_dma_obj *obj;
        int error, i;

        for (i = 0; i < count; i++) {
                obj = uma_zalloc(linux_dma_obj_zone, flags);
                if (obj == NULL)
                        break;

                error = bus_dmamem_alloc(pool->pool_dmat, &obj->vaddr,
                    BUS_DMA_NOWAIT, &obj->dmamap);
                if (error!= 0) {
                        uma_zfree(linux_dma_obj_zone, obj);
                        break;
                }

                store[i] = obj;
        }

        return (i);
}

static void
dma_pool_obj_release(void *arg, void **store, int count)
{
        struct dma_pool *pool = arg;
        struct linux_dma_obj *obj;
        int i;

        for (i = 0; i < count; i++) {
                obj = store[i];
                bus_dmamem_free(pool->pool_dmat, obj->vaddr, obj->dmamap);
                uma_zfree(linux_dma_obj_zone, obj);
        }
}

struct dma_pool *
linux_dma_pool_create(char *name, struct device *dev, size_t size,
    size_t align, size_t boundary)
{
        struct linux_dma_priv *priv;
        struct dma_pool *pool;

        priv = dev->dma_priv;

        pool = kzalloc(sizeof(*pool), GFP_KERNEL);
        pool->pool_device = dev;
        pool->pool_entry_size = size;

        if (bus_dma_tag_create(bus_get_dma_tag(dev->bsddev),
            align, boundary,            /* alignment, boundary */
            priv->dma_mask,             /* lowaddr */
            BUS_SPACE_MAXADDR,          /* highaddr */
            NULL, NULL,                 /* filtfunc, filtfuncarg */
            size,                       /* maxsize */
            1,                          /* nsegments */
            size,                       /* maxsegsz */
            0,                          /* flags */
            NULL, NULL,                 /* lockfunc, lockfuncarg */
            &pool->pool_dmat)) {
                kfree(pool);
                return (NULL);
        }

        pool->pool_zone = uma_zcache_create(name, -1, dma_pool_obj_ctor,
            dma_pool_obj_dtor, NULL, NULL, dma_pool_obj_import,
            dma_pool_obj_release, pool, 0);

        mtx_init(&pool->pool_lock, "lkpi-dma-pool", NULL, MTX_DEF);
        pctrie_init(&pool->pool_ptree);

        return (pool);
}

void
linux_dma_pool_destroy(struct dma_pool *pool)
{

        uma_zdestroy(pool->pool_zone);
        bus_dma_tag_destroy(pool->pool_dmat);
        mtx_destroy(&pool->pool_lock);
        kfree(pool);
}

void
lkpi_dmam_pool_destroy(struct device *dev, void *p)
{
        struct dma_pool *pool;

        pool = *(struct dma_pool **)p;
        LINUX_DMA_PCTRIE_RECLAIM(&pool->pool_ptree);
        linux_dma_pool_destroy(pool);
}

void *
linux_dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
    dma_addr_t *handle)
{
        struct linux_dma_obj *obj;

        obj = uma_zalloc_arg(pool->pool_zone, pool, mem_flags & GFP_NATIVE_MASK);
        if (obj == NULL)
                return (NULL);

        DMA_POOL_LOCK(pool);
        if (LINUX_DMA_PCTRIE_INSERT(&pool->pool_ptree, obj) != 0) {
                DMA_POOL_UNLOCK(pool);
                uma_zfree_arg(pool->pool_zone, obj, pool);
                return (NULL);
        }
        DMA_POOL_UNLOCK(pool);

        *handle = obj->dma_addr;
        return (obj->vaddr);
}

void
linux_dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma_addr)
{
        struct linux_dma_obj *obj;

        DMA_POOL_LOCK(pool);
        obj = LINUX_DMA_PCTRIE_LOOKUP(&pool->pool_ptree, dma_addr);
        if (obj == NULL) {
                DMA_POOL_UNLOCK(pool);
                return;
        }
        LINUX_DMA_PCTRIE_REMOVE(&pool->pool_ptree, dma_addr);
        DMA_POOL_UNLOCK(pool);

        uma_zfree_arg(pool->pool_zone, obj, pool);
}

static int
linux_backlight_get_status(device_t dev, struct backlight_props *props)
{
        struct pci_dev *pdev;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);

        props->brightness = pdev->dev.bd->props.brightness;
        props->brightness = props->brightness * 100 / pdev->dev.bd->props.max_brightness;
        props->nlevels = 0;

        return (0);
}

static int
linux_backlight_get_info(device_t dev, struct backlight_info *info)
{
        struct pci_dev *pdev;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);

        info->type = BACKLIGHT_TYPE_PANEL;
        strlcpy(info->name, pdev->dev.bd->name, BACKLIGHTMAXNAMELENGTH);
        return (0);
}

static int
linux_backlight_update_status(device_t dev, struct backlight_props *props)
{
        struct pci_dev *pdev;

        linux_set_current(curthread);
        pdev = device_get_softc(dev);

        pdev->dev.bd->props.brightness = pdev->dev.bd->props.max_brightness *
                props->brightness / 100;
        pdev->dev.bd->props.power = props->brightness == 0 ?
                4/* FB_BLANK_POWERDOWN */ : 0/* FB_BLANK_UNBLANK */;
        return (pdev->dev.bd->ops->update_status(pdev->dev.bd));
}

struct backlight_device *
linux_backlight_device_register(const char *name, struct device *dev,
    void *data, const struct backlight_ops *ops, struct backlight_properties *props)
{

        dev->bd = malloc(sizeof(*dev->bd), M_DEVBUF, M_WAITOK | M_ZERO);
        dev->bd->ops = ops;
        dev->bd->props.type = props->type;
        dev->bd->props.max_brightness = props->max_brightness;
        dev->bd->props.brightness = props->brightness;
        dev->bd->props.power = props->power;
        dev->bd->data = data;
        dev->bd->dev = dev;
        dev->bd->name = strdup(name, M_DEVBUF);

        dev->backlight_dev = backlight_register(name, dev->bsddev);

        return (dev->bd);
}

void
linux_backlight_device_unregister(struct backlight_device *bd)
{

        backlight_destroy(bd->dev->backlight_dev);
        free(bd->name, M_DEVBUF);
        free(bd, M_DEVBUF);
}