source: mainline/uspace/drv/bus/pci/pciintel/pci.c

/*
 * Copyright (c) 2025 Jiri Svoboda
 * Copyright (c) 2010 Lenka Trochtova
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * 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.
 */

/**
 * @addtogroup pciintel
 * @{
 */

/** @file
 */

#include <assert.h>
#include <byteorder.h>
#include <stdio.h>
#include <errno.h>
#include <stdbool.h>
#include <fibril_synch.h>
#include <str.h>
#include <ctype.h>
#include <macros.h>
#include <str_error.h>

#include <ddf/driver.h>
#include <ddf/log.h>
#include <ipc/dev_iface.h>
#include <irc.h>
#include <ops/hw_res.h>
#include <device/hw_res.h>
#include <ops/pio_window.h>
#include <device/pio_window.h>
#include <ddi.h>
#include <pci_dev_iface.h>

#include "ctl.h"
#include "pci.h"
#include "pci_regs.h"

#define NAME "pciintel"

#define CONF_ADDR_ENABLE        (((unsigned)1) << 31)
#define CONF_ADDR(bus, dev, fn, reg) \
        ((bus << 16) | (dev << 11) | (fn << 8) | (reg & ~3))

/** Obtain PCI function soft-state from DDF function node */
static pci_fun_t *pci_fun(ddf_fun_t *fnode)
{
        return ddf_fun_data_get(fnode);
}

/** Obtain PCI bus soft-state from DDF device node */
pci_bus_t *pci_bus(ddf_dev_t *dnode)
{
        return ddf_dev_data_get(dnode);
}

/** Obtain PCI bus soft-state from function soft-state */
static pci_bus_t *pci_bus_from_fun(pci_fun_t *fun)
{
        return fun->busptr;
}

/** Max is 47, align to something nice. */
#define ID_MAX_STR_LEN 50

static hw_resource_list_t *pciintel_get_resources(ddf_fun_t *fnode)
{
        pci_fun_t *fun = pci_fun(fnode);

        if (fun == NULL)
                return NULL;
        return &fun->hw_resources;
}

static bool pciintel_fun_owns_interrupt(pci_fun_t *fun, int irq)
{
        size_t i;
        hw_resource_list_t *res = &fun->hw_resources;

        for (i = 0; i < res->count; i++) {
                if (res->resources[i].type == INTERRUPT &&
                    res->resources[i].res.interrupt.irq == irq) {
                        return true;
                }
        }

        return false;
}

static errno_t pciintel_enable_interrupt(ddf_fun_t *fnode, int irq)
{
        pci_fun_t *fun = pci_fun(fnode);

        if (!pciintel_fun_owns_interrupt(fun, irq))
                return EINVAL;

        return irc_enable_interrupt(irq);
}

static errno_t pciintel_disable_interrupt(ddf_fun_t *fnode, int irq)
{
        pci_fun_t *fun = pci_fun(fnode);

        if (!pciintel_fun_owns_interrupt(fun, irq))
                return EINVAL;

        return irc_disable_interrupt(irq);
}

static errno_t pciintel_clear_interrupt(ddf_fun_t *fnode, int irq)
{
        pci_fun_t *fun = pci_fun(fnode);

        if (!pciintel_fun_owns_interrupt(fun, irq))
                return EINVAL;

        return irc_clear_interrupt(irq);
}

/** Handle legacy IO availability query from function.
 *
 * @param fnode Function performing the query
 * @param rclaims Place to store the legacy IO claims bitmask
 * @return EOK on success or an error code
 */
static errno_t pciintel_query_legacy_io(ddf_fun_t *fnode,
    hw_res_claims_t *rclaims)
{
        pci_fun_t *fun = pci_fun(fnode);
        pci_bus_t *bus = fun->busptr;
        pci_fun_t *f;
        hw_res_claims_t claims;

        /*
         * We need to wait for enumeration to complete so that we give
         * the PCI IDE driver a chance to claim the legacy ISA IDE
         * ranges.
         */
        ddf_msg(LVL_DEBUG, "pciintel_query_legacy_io");

        fun->querying = true;

        fibril_mutex_lock(&bus->enum_done_lock);
        while (!bus->enum_done)
                fibril_condvar_wait(&bus->enum_done_cv, &bus->enum_done_lock);
        fibril_mutex_unlock(&bus->enum_done_lock);

        ddf_msg(LVL_DEBUG, "Wait for PCI devices to stabilize");

        f = pci_fun_first(bus);
        while (f != NULL) {
                if (!f->querying)
                        ddf_fun_wait_stable(f->fnode);
                f = pci_fun_next(f);
        }

        /* Devices are stable. Now we can determine if ISA IDE was claimed. */

        claims = 0;

        ddf_msg(LVL_DEBUG, "PCI devices stabilized, leg_ide_claimed=%d\n",
            (int)bus->leg_ide_claimed);
        if (bus->leg_ide_claimed != false) {
                ddf_msg(LVL_NOTE, "Legacy IDE I/O ports claimed by PCI driver.");
                claims |= hwc_isa_ide;
        }

        fun->querying = false;
        *rclaims = claims;
        return EOK;
}

/** Handle legacy IO claim from function.
 *
 * @param fnode Function claiming the legacy I/O ports
 * @param claims Bitmask of claimed I/O
 * @return EOK on success or an error code
 */
static errno_t pciintel_claim_legacy_io(ddf_fun_t *fnode,
    hw_res_claims_t claims)
{
        pci_fun_t *fun = pci_fun(fnode);
        pci_bus_t *bus = fun->busptr;

        ddf_msg(LVL_DEBUG, "pciintel_claim_legacy_io() claims=%x", claims);
        if ((claims & hwc_isa_ide) != 0)
                bus->leg_ide_claimed = true;

        return EOK;
}

static pio_window_t *pciintel_get_pio_window(ddf_fun_t *fnode)
{
        pci_fun_t *fun = pci_fun(fnode);

        if (fun == NULL)
                return NULL;
        return &fun->pio_window;
}

static errno_t config_space_write_32(ddf_fun_t *fun, uint32_t address,
    uint32_t data)
{
        if (address > 252)
                return EINVAL;
        pci_conf_write_32(pci_fun(fun), address, data);
        return EOK;
}

static errno_t config_space_write_16(
    ddf_fun_t *fun, uint32_t address, uint16_t data)
{
        if (address > 254)
                return EINVAL;
        pci_conf_write_16(pci_fun(fun), address, data);
        return EOK;
}

static errno_t config_space_write_8(
    ddf_fun_t *fun, uint32_t address, uint8_t data)
{
        if (address > 255)
                return EINVAL;
        pci_conf_write_8(pci_fun(fun), address, data);
        return EOK;
}

static errno_t config_space_read_32(
    ddf_fun_t *fun, uint32_t address, uint32_t *data)
{
        if (address > 252)
                return EINVAL;
        *data = pci_conf_read_32(pci_fun(fun), address);
        return EOK;
}

static errno_t config_space_read_16(
    ddf_fun_t *fun, uint32_t address, uint16_t *data)
{
        if (address > 254)
                return EINVAL;
        *data = pci_conf_read_16(pci_fun(fun), address);
        return EOK;
}

static errno_t config_space_read_8(
    ddf_fun_t *fun, uint32_t address, uint8_t *data)
{
        if (address > 255)
                return EINVAL;
        *data = pci_conf_read_8(pci_fun(fun), address);
        return EOK;
}

static hw_res_ops_t pciintel_hw_res_ops = {
        .get_resource_list = &pciintel_get_resources,
        .enable_interrupt = &pciintel_enable_interrupt,
        .disable_interrupt = &pciintel_disable_interrupt,
        .clear_interrupt = &pciintel_clear_interrupt,
        .query_legacy_io = &pciintel_query_legacy_io,
        .claim_legacy_io = &pciintel_claim_legacy_io
};

static pio_window_ops_t pciintel_pio_window_ops = {
        .get_pio_window = &pciintel_get_pio_window
};

static pci_dev_iface_t pci_dev_ops = {
        .config_space_read_8 = &config_space_read_8,
        .config_space_read_16 = &config_space_read_16,
        .config_space_read_32 = &config_space_read_32,
        .config_space_write_8 = &config_space_write_8,
        .config_space_write_16 = &config_space_write_16,
        .config_space_write_32 = &config_space_write_32
};

static ddf_dev_ops_t pci_fun_ops = {
        .interfaces[HW_RES_DEV_IFACE] = &pciintel_hw_res_ops,
        .interfaces[PIO_WINDOW_DEV_IFACE] = &pciintel_pio_window_ops,
        .interfaces[PCI_DEV_IFACE] = &pci_dev_ops
};

static errno_t pci_dev_add(ddf_dev_t *);
static errno_t pci_fun_online(ddf_fun_t *);
static errno_t pci_fun_offline(ddf_fun_t *);

/** PCI bus driver standard operations */
static driver_ops_t pci_ops = {
        .dev_add = &pci_dev_add,
        .fun_online = &pci_fun_online,
        .fun_offline = &pci_fun_offline,
};

/** PCI bus driver structure */
static driver_t pci_driver = {
        .name = NAME,
        .driver_ops = &pci_ops
};

static void pci_conf_read(pci_fun_t *fun, int reg, uint8_t *buf, size_t len)
{
        const uint32_t conf_addr = CONF_ADDR(fun->bus, fun->dev, fun->fn, reg);
        pci_bus_t *bus = pci_bus_from_fun(fun);
        uint32_t val;

        fibril_mutex_lock(&bus->conf_mutex);

        if (bus->conf_addr_reg) {
                pio_write_32(bus->conf_addr_reg,
                    host2uint32_t_le(CONF_ADDR_ENABLE | conf_addr));
                /*
                 * Always read full 32-bits from the PCI conf_data_port
                 * register and get the desired portion of it afterwards. Some
                 * architectures do not support shorter PIO reads offset from
                 * this register.
                 */
                val = uint32_t_le2host(pio_read_32(bus->conf_data_reg));
        } else {
                val = uint32_t_le2host(pio_read_32(
                    &bus->conf_space[conf_addr / sizeof(ioport32_t)]));
        }

        switch (len) {
        case 1:
                *buf = (uint8_t) (val >> ((reg & 3) * 8));
                break;
        case 2:
                *((uint16_t *) buf) = (uint16_t) (val >> ((reg & 3)) * 8);
                break;
        case 4:
                *((uint32_t *) buf) = (uint32_t) val;
                break;
        }

        fibril_mutex_unlock(&bus->conf_mutex);
}

static void pci_conf_write(pci_fun_t *fun, int reg, uint8_t *buf, size_t len)
{
        const uint32_t conf_addr = CONF_ADDR(fun->bus, fun->dev, fun->fn, reg);
        pci_bus_t *bus = pci_bus_from_fun(fun);
        uint32_t val = 0;

        fibril_mutex_lock(&bus->conf_mutex);

        /*
         * Prepare to write full 32-bits to the PCI conf_data_port register.
         * Some architectures do not support shorter PIO writes offset from this
         * register.
         */

        if (len < 4) {
                /*
                 * We have fewer than full 32-bits, so we need to read the
                 * missing bits first.
                 */
                if (bus->conf_addr_reg) {
                        pio_write_32(bus->conf_addr_reg,
                            host2uint32_t_le(CONF_ADDR_ENABLE | conf_addr));
                        val = uint32_t_le2host(pio_read_32(bus->conf_data_reg));
                } else {
                        val = uint32_t_le2host(pio_read_32(
                            &bus->conf_space[conf_addr / sizeof(ioport32_t)]));
                }
        }

        switch (len) {
        case 1:
                val &= ~(0xffU << ((reg & 3) * 8));
                val |= *buf << ((reg & 3) * 8);
                break;
        case 2:
                val &= ~(0xffffU << ((reg & 3) * 8));
                val |= *((uint16_t *) buf) << ((reg & 3) * 8);
                break;
        case 4:
                val = *((uint32_t *) buf);
                break;
        }

        if (bus->conf_addr_reg) {
                pio_write_32(bus->conf_addr_reg,
                    host2uint32_t_le(CONF_ADDR_ENABLE | conf_addr));
                pio_write_32(bus->conf_data_reg, host2uint32_t_le(val));
        } else {
                pio_write_32(&bus->conf_space[conf_addr / sizeof(ioport32_t)],
                    host2uint32_t_le(val));
        }

        fibril_mutex_unlock(&bus->conf_mutex);
}

uint8_t pci_conf_read_8(pci_fun_t *fun, int reg)
{
        uint8_t res;
        pci_conf_read(fun, reg, &res, 1);
        return res;
}

uint16_t pci_conf_read_16(pci_fun_t *fun, int reg)
{
        uint16_t res;
        pci_conf_read(fun, reg, (uint8_t *) &res, 2);
        return res;
}

uint32_t pci_conf_read_32(pci_fun_t *fun, int reg)
{
        uint32_t res;
        pci_conf_read(fun, reg, (uint8_t *) &res, 4);
        return res;
}

void pci_conf_write_8(pci_fun_t *fun, int reg, uint8_t val)
{
        pci_conf_write(fun, reg, (uint8_t *) &val, 1);
}

void pci_conf_write_16(pci_fun_t *fun, int reg, uint16_t val)
{
        pci_conf_write(fun, reg, (uint8_t *) &val, 2);
}

void pci_conf_write_32(pci_fun_t *fun, int reg, uint32_t val)
{
        pci_conf_write(fun, reg, (uint8_t *) &val, 4);
}

void pci_fun_create_match_ids(pci_fun_t *fun)
{
        errno_t rc;
        int ret;
        char match_id_str[ID_MAX_STR_LEN];

        /* Vendor ID & Device ID, length(incl \0) 22 */
        ret = snprintf(match_id_str, ID_MAX_STR_LEN, "pci/ven=%04"
            PRIx16 "&dev=%04" PRIx16, fun->vendor_id, fun->device_id);
        if (ret < 0) {
                ddf_msg(LVL_ERROR, "Failed creating match ID str");
        }

        rc = ddf_fun_add_match_id(fun->fnode, match_id_str, 90);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed adding match ID: %s", str_error(rc));
        }

        /* Class, subclass, prog IF, revision, length(incl \0) 47 */
        ret = snprintf(match_id_str, ID_MAX_STR_LEN,
            "pci/class=%02x&subclass=%02x&progif=%02x&revision=%02x",
            fun->class_code, fun->subclass_code, fun->prog_if, fun->revision);
        if (ret < 0) {
                ddf_msg(LVL_ERROR, "Failed creating match ID str");
        }

        rc = ddf_fun_add_match_id(fun->fnode, match_id_str, 70);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed adding match ID: %s", str_error(rc));
        }

        /* Class, subclass, prog IF, length(incl \0) 35 */
        ret = snprintf(match_id_str, ID_MAX_STR_LEN,
            "pci/class=%02x&subclass=%02x&progif=%02x",
            fun->class_code, fun->subclass_code, fun->prog_if);
        if (ret < 0) {
                ddf_msg(LVL_ERROR, "Failed creating match ID str");
        }

        rc = ddf_fun_add_match_id(fun->fnode, match_id_str, 60);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed adding match ID: %s", str_error(rc));
        }

        /* Class, subclass, length(incl \0) 25 */
        ret = snprintf(match_id_str, ID_MAX_STR_LEN,
            "pci/class=%02x&subclass=%02x",
            fun->class_code, fun->subclass_code);
        if (ret < 0) {
                ddf_msg(LVL_ERROR, "Failed creating match ID str");
        }

        rc = ddf_fun_add_match_id(fun->fnode, match_id_str, 50);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed adding match ID: %s", str_error(rc));
        }

        /* Class, length(incl \0) 13 */
        ret = snprintf(match_id_str, ID_MAX_STR_LEN, "pci/class=%02x",
            fun->class_code);
        if (ret < 0) {
                ddf_msg(LVL_ERROR, "Failed creating match ID str");
        }

        rc = ddf_fun_add_match_id(fun->fnode, match_id_str, 40);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed adding match ID: %s", str_error(rc));
        }

        /* TODO add subsys ids, but those exist only in header type 0 */
}

/** Get first PCI function.
 *
 * @param bus PCI bus
 * @return First PCI function on @a bus or @c NULL if there is none
 */
pci_fun_t *pci_fun_first(pci_bus_t *bus)
{
        link_t *link;

        link = list_first(&bus->funs);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, pci_fun_t, lfuns);
}

/** Get next PCI function.
 *
 * @param cur Current function
 * @return Next PCI function on the same bus or @c NULL if there is none
 */
pci_fun_t *pci_fun_next(pci_fun_t *cur)
{
        link_t *link;

        link = list_next(&cur->lfuns, &cur->busptr->funs);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, pci_fun_t, lfuns);
}

void pci_add_range(pci_fun_t *fun, uint64_t range_addr, size_t range_size,
    bool io)
{
        hw_resource_list_t *hw_res_list = &fun->hw_resources;
        hw_resource_t *hw_resources =  hw_res_list->resources;
        size_t count = hw_res_list->count;

        assert(hw_resources != NULL);
        assert(count < PCI_MAX_HW_RES);

        if (io) {
                hw_resources[count].type = IO_RANGE;
                hw_resources[count].res.io_range.address = range_addr;
                hw_resources[count].res.io_range.size = range_size;
                hw_resources[count].res.io_range.relative = true;
                hw_resources[count].res.io_range.endianness = LITTLE_ENDIAN;
        } else {
                hw_resources[count].type = MEM_RANGE;
                hw_resources[count].res.mem_range.address = range_addr;
                hw_resources[count].res.mem_range.size = range_size;
                hw_resources[count].res.mem_range.relative = false;
                hw_resources[count].res.mem_range.endianness = LITTLE_ENDIAN;
        }

        hw_res_list->count++;
}

/** Read the base address register (BAR) of the device and if it contains valid
 * address add it to the devices hw resource list.
 *
 * @param fun   PCI function
 * @param addr  The address of the BAR in the PCI configuration address space of
 *              the device
 * @return      The addr the address of the BAR which should be read next
 */
int pci_read_bar(pci_fun_t *fun, int addr)
{
        /* Value of the BAR */
        uint32_t val;
        uint32_t bar;
        uint32_t mask;

        /* IO space address */
        bool io;
        /* 64-bit wide address */
        bool addrw64;

        /* Size of the io or memory range specified by the BAR */
        size_t range_size;
        /* Beginning of the io or memory range specified by the BAR */
        uint64_t range_addr;

        /* Get the value of the BAR. */
        val = pci_conf_read_32(fun, addr);

#define IO_MASK  (~0x3)
#define MEM_MASK (~0xf)

        io = (val & 1) != 0;
        if (io) {
                addrw64 = false;
                mask = IO_MASK;
        } else {
                mask = MEM_MASK;
                switch ((val >> 1) & 3) {
                case 0:
                        addrw64 = false;
                        break;
                case 2:
                        addrw64 = true;
                        break;
                default:
                        /* reserved, go to the next BAR */
                        return addr + 4;
                }
        }

        /* Get the address mask. */
        pci_conf_write_32(fun, addr, 0xffffffff);
        bar = pci_conf_read_32(fun, addr);

        /*
         * Unimplemented BARs read back as all 0's.
         */
        if (!bar)
                return addr + (addrw64 ? 8 : 4);

        mask &= bar;

        /* Restore the original value. */
        pci_conf_write_32(fun, addr, val);
        val = pci_conf_read_32(fun, addr);

        range_size = pci_bar_mask_to_size(mask);

        if (addrw64) {
                range_addr = ((uint64_t)pci_conf_read_32(fun, addr + 4) << 32) |
                    (val & 0xfffffff0);
        } else {
                range_addr = (val & 0xfffffff0);
        }

        if (range_addr != 0) {
                ddf_msg(LVL_DEBUG, "Function %s : address = %" PRIx64
                    ", size = %x", ddf_fun_get_name(fun->fnode), range_addr,
                    (unsigned int) range_size);
        }

        pci_add_range(fun, range_addr, range_size, io);

        if (addrw64)
                return addr + 8;

        return addr + 4;
}

void pci_add_interrupt(pci_fun_t *fun, int irq)
{
        hw_resource_list_t *hw_res_list = &fun->hw_resources;
        hw_resource_t *hw_resources = hw_res_list->resources;
        size_t count = hw_res_list->count;

        assert(NULL != hw_resources);
        assert(count < PCI_MAX_HW_RES);

        hw_resources[count].type = INTERRUPT;
        hw_resources[count].res.interrupt.irq = irq;

        hw_res_list->count++;

        ddf_msg(LVL_NOTE, "Function %s uses irq %x.", ddf_fun_get_name(fun->fnode), irq);
}

void pci_read_interrupt(pci_fun_t *fun)
{
        uint8_t irq = pci_conf_read_8(fun, PCI_BRIDGE_INT_LINE);
        uint8_t pin = pci_conf_read_8(fun, PCI_BRIDGE_INT_PIN);

        if (pin != 0 && irq != 0xff)
                pci_add_interrupt(fun, irq);
}

/** Enumerate (recursively) and register the devices connected to a pci bus.
 *
 * @param bus           Host-to-PCI bridge
 * @param bus_num       Bus number
 *
 * @return EOK on success, ENOENT if no PCI devices found, ENOMEM if out of
 *         memory, EIO on other I/O error
 */
errno_t pci_bus_scan(pci_bus_t *bus, int bus_num)
{
        pci_fun_t *fun;
        errno_t rc;

        int child_bus = 0;
        int dnum, fnum;
        bool multi;
        uint8_t header_type;
        bool device_found;

        device_found = false;

        for (dnum = 0; dnum < 32; dnum++) {
                multi = true;
                for (fnum = 0; multi && fnum < 8; fnum++) {
                        fun = pci_fun_new(bus);

                        pci_fun_init(fun, bus_num, dnum, fnum);
                        if (fun->vendor_id == 0xffff) {
                                pci_fun_delete(fun);
                                /*
                                 * The device is not present, go on scanning the
                                 * bus.
                                 */
                                if (fnum == 0)
                                        break;
                                else
                                        continue;
                        }

                        device_found = true;

                        header_type = pci_conf_read_8(fun, PCI_HEADER_TYPE);
                        if (fnum == 0) {
                                /* Is the device multifunction? */
                                multi = header_type >> 7;
                        }
                        /* Clear the multifunction bit. */
                        header_type = header_type & 0x7F;

                        char *fun_name = pci_fun_create_name(fun);
                        if (fun_name == NULL) {
                                ddf_msg(LVL_ERROR, "Out of memory.");
                                pci_fun_delete(fun);
                                return ENOMEM;
                        }

                        rc = ddf_fun_set_name(fun->fnode, fun_name);
                        free(fun_name);
                        if (rc != EOK) {
                                ddf_msg(LVL_ERROR, "Failed setting function name.");
                                pci_fun_delete(fun);
                                return EIO;
                        }

                        pci_alloc_resource_list(fun);
                        pci_read_bars(fun);
                        pci_read_interrupt(fun);

                        /* Propagate the PIO window to the function. */
                        fun->pio_window = bus->pio_win;

                        ddf_fun_set_ops(fun->fnode, &pci_fun_ops);

                        ddf_msg(LVL_DEBUG, "Adding new function %s.",
                            ddf_fun_get_name(fun->fnode));

                        pci_fun_create_match_ids(fun);

                        if (header_type == PCI_HEADER_TYPE_BRIDGE ||
                            header_type == PCI_HEADER_TYPE_CARDBUS) {
                                child_bus = pci_conf_read_8(fun,
                                    PCI_BRIDGE_SEC_BUS_NUM);
                                ddf_msg(LVL_DEBUG, "Device is pci-to-pci "
                                    "bridge, secondary bus number = %d.",
                                    bus_num);
                                if (child_bus > bus_num) {
                                        rc = pci_bus_scan(bus, child_bus);
                                        if (rc != EOK && rc != ENOENT) {
                                                pci_fun_delete(fun);
                                                return rc;
                                        }
                                }
                        }

                        if (ddf_fun_bind(fun->fnode) != EOK) {
                                pci_clean_resource_list(fun);
                                pci_fun_delete(fun);
                                continue;
                        }

                        list_append(&fun->lfuns, &bus->funs);
                }
        }

        /* Fail bus scan if no devices are found. */
        if (!device_found)
                return ENOENT;

        return EOK;
}

static errno_t pci_dev_add(ddf_dev_t *dnode)
{
        hw_resource_list_t hw_resources;
        pci_bus_t *bus = NULL;
        ddf_fun_t *ctl = NULL;
        bool got_res = false;
        async_sess_t *sess;
        errno_t rc;

        ddf_msg(LVL_DEBUG, "pci_dev_add");

        bus = ddf_dev_data_alloc(dnode, sizeof(pci_bus_t));
        if (bus == NULL) {
                ddf_msg(LVL_ERROR, "pci_dev_add allocation failed.");
                rc = ENOMEM;
                goto fail;
        }

        list_initialize(&bus->funs);
        fibril_mutex_initialize(&bus->conf_mutex);
        fibril_mutex_initialize(&bus->enum_done_lock);
        fibril_condvar_initialize(&bus->enum_done_cv);

        bus->dnode = dnode;

        sess = ddf_dev_parent_sess_get(dnode);
        if (sess == NULL) {
                ddf_msg(LVL_ERROR, "pci_dev_add failed to connect to the "
                    "parent driver.");
                rc = ENOENT;
                goto fail;
        }

        rc = pio_window_get(sess, &bus->pio_win);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "pci_dev_add failed to get PIO window "
                    "for the device.");
                goto fail;
        }

        rc = hw_res_get_resource_list(sess, &hw_resources);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "pci_dev_add failed to get hw resources "
                    "for the device.");
                goto fail;
        }
        got_res = true;

        assert(hw_resources.count >= 1);

        if (hw_resources.count == 1) {
                assert(hw_resources.resources[0].type == MEM_RANGE);

                ddf_msg(LVL_DEBUG, "conf_addr_space = %" PRIx64 ".",
                    hw_resources.resources[0].res.mem_range.address);

                if (pio_enable_resource(&bus->pio_win,
                    &hw_resources.resources[0], (void **) &bus->conf_space,
                    NULL, NULL)) {
                        ddf_msg(LVL_ERROR,
                            "Failed to map configuration space.");
                        rc = EADDRNOTAVAIL;
                        goto fail;
                }

        } else {
                assert(hw_resources.resources[0].type == IO_RANGE);
                assert(hw_resources.resources[0].res.io_range.size >= 4);

                assert(hw_resources.resources[1].type == IO_RANGE);
                assert(hw_resources.resources[1].res.io_range.size >= 4);

                ddf_msg(LVL_DEBUG, "conf_addr = %" PRIx64 ".",
                    hw_resources.resources[0].res.io_range.address);
                ddf_msg(LVL_DEBUG, "data_addr = %" PRIx64 ".",
                    hw_resources.resources[1].res.io_range.address);

                if (pio_enable_resource(&bus->pio_win,
                    &hw_resources.resources[0], (void **) &bus->conf_addr_reg,
                    NULL, NULL)) {
                        ddf_msg(LVL_ERROR,
                            "Failed to enable configuration ports.");
                        rc = EADDRNOTAVAIL;
                        goto fail;
                }
                if (pio_enable_resource(&bus->pio_win,
                    &hw_resources.resources[1], (void **) &bus->conf_data_reg,
                    NULL, NULL)) {
                        ddf_msg(LVL_ERROR,
                            "Failed to enable configuration ports.");
                        rc = EADDRNOTAVAIL;
                        goto fail;
                }
        }

        /* Make the bus device more visible. It has no use yet. */
        ddf_msg(LVL_DEBUG, "Adding a 'ctl' function");

        ctl = ddf_fun_create(bus->dnode, fun_exposed, "ctl");
        if (ctl == NULL) {
                ddf_msg(LVL_ERROR, "Failed creating control function.");
                rc = ENOMEM;
                goto fail;
        }

        ddf_fun_set_conn_handler(ctl, pci_ctl_connection);

        /* Enumerate functions. */
        ddf_msg(LVL_DEBUG, "Enumerating the bus");
        rc = pci_bus_scan(bus, 0);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Bus enumeration failed.");
                goto fail;
        }

        rc = ddf_fun_bind(ctl);
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed binding control function.");
                goto fail;
        }

        rc = ddf_fun_add_to_category(ctl, "pci");
        if (rc != EOK) {
                ddf_msg(LVL_ERROR, "Failed adding control function to category "
                    "'pci'.");
                goto fail;
        }

        hw_res_clean_resource_list(&hw_resources);

        ddf_msg(LVL_DEBUG, "Bus enumeration done.");

        fibril_mutex_lock(&bus->enum_done_lock);
        bus->enum_done = true;
        fibril_mutex_unlock(&bus->enum_done_lock);
        fibril_condvar_broadcast(&bus->enum_done_cv);

        return EOK;
fail:
        if (got_res)
                hw_res_clean_resource_list(&hw_resources);

        if (ctl != NULL)
                ddf_fun_destroy(ctl);

        return rc;
}

static errno_t pci_fun_online(ddf_fun_t *fun)
{
        ddf_msg(LVL_DEBUG, "pci_fun_online()");
        return ddf_fun_online(fun);
}

static errno_t pci_fun_offline(ddf_fun_t *fun)
{
        ddf_msg(LVL_DEBUG, "pci_fun_offline()");
        return ddf_fun_offline(fun);
}

static void pciintel_init(void)
{
        ddf_log_init(NAME);
}

pci_fun_t *pci_fun_new(pci_bus_t *bus)
{
        pci_fun_t *fun;
        ddf_fun_t *fnode;

        fnode = ddf_fun_create(bus->dnode, fun_inner, NULL);
        if (fnode == NULL)
                return NULL;

        fun = ddf_fun_data_alloc(fnode, sizeof(pci_fun_t));
        if (fun == NULL)
                return NULL;

        fun->busptr = bus;
        fun->fnode = fnode;
        return fun;
}

void pci_fun_init(pci_fun_t *fun, int bus, int dev, int fn)
{
        fun->bus = bus;
        fun->dev = dev;
        fun->fn = fn;
        fun->vendor_id = pci_conf_read_16(fun, PCI_VENDOR_ID);
        fun->device_id = pci_conf_read_16(fun, PCI_DEVICE_ID);

        /* Explicitly enable PCI bus mastering */
        fun->command = pci_conf_read_16(fun, PCI_COMMAND) |
            PCI_COMMAND_MASTER;
        pci_conf_write_16(fun, PCI_COMMAND, fun->command);

        fun->class_code = pci_conf_read_8(fun, PCI_BASE_CLASS);
        fun->subclass_code = pci_conf_read_8(fun, PCI_SUB_CLASS);
        fun->prog_if = pci_conf_read_8(fun, PCI_PROG_IF);
        fun->revision = pci_conf_read_8(fun, PCI_REVISION_ID);
}

void pci_fun_delete(pci_fun_t *fun)
{
        hw_res_clean_resource_list(&fun->hw_resources);
        if (fun->fnode != NULL)
                ddf_fun_destroy(fun->fnode);
}

char *pci_fun_create_name(pci_fun_t *fun)
{
        char *name = NULL;

        asprintf(&name, "%02x:%02x.%01x", fun->bus, fun->dev,
            fun->fn);
        return name;
}

bool pci_alloc_resource_list(pci_fun_t *fun)
{
        fun->hw_resources.resources = fun->resources;
        return true;
}

void pci_clean_resource_list(pci_fun_t *fun)
{
        fun->hw_resources.resources = NULL;
}

/** Read the base address registers (BARs) of the function and add the addresses
 * to its HW resource list.
 *
 * @param fun   PCI function
 */
void pci_read_bars(pci_fun_t *fun)
{
        /*
         * Position of the BAR in the PCI configuration address space of the
         * device.
         */
        int addr = PCI_BASE_ADDR_0;

        while (addr <= PCI_BASE_ADDR_5)
                addr = pci_read_bar(fun, addr);
}

size_t pci_bar_mask_to_size(uint32_t mask)
{
        size_t size = mask & ~(mask - 1);
        return size;
}

int main(int argc, char *argv[])
{
        printf(NAME ": HelenOS PCI bus driver (Intel method 1).\n");
        pciintel_init();
        return ddf_driver_main(&pci_driver);
}

/**
 * @}
 */