/*
 * EHCI HCD (Host Controller Driver) PCI Bus Glue.
 *
 * Copyright (c) 2000-2004 by David Brownell
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef CONFIG_PCI
#error "This file is PCI bus glue.  CONFIG_PCI must be defined."
#endif

/* defined here to avoid adding to pci_ids.h for single instance use */
#define PCI_DEVICE_ID_INTEL_CE4100_USB  0x2e70

/*-------------------------------------------------------------------------*/

/* called after powerup, by probe or system-pm "wakeup" */
static int ehci_pci_reinit(struct ehci_hcd *ehci, struct pci_dev *pdev)
{
        int                     retval;

        /* we expect static quirk code to handle the "extended capabilities"
         * (currently just BIOS handoff) allowed starting with EHCI 0.96
         */

        /* PCI Memory-Write-Invalidate cycle support is optional (uncommon) */
        retval = pci_set_mwi(pdev);
        if (!retval)
                ehci_dbg(ehci, "MWI active\n");

        return 0;
}

/* called during probe() after chip reset completes */
static int ehci_pci_setup(struct usb_hcd *hcd)
{
        struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
        struct pci_dev          *pdev = to_pci_dev(hcd->self.controller);
        struct pci_dev          *p_smbus;
        u8                      rev;
        u32                     temp;
        int                     retval;

        switch (pdev->vendor) {
        case PCI_VENDOR_ID_TOSHIBA_2:
                /* celleb's companion chip */
                if (pdev->device == 0x01b5) {
#ifdef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
                        ehci->big_endian_mmio = 1;
#else
                        ehci_warn(ehci,
                                  "unsupported big endian Toshiba quirk\n");
#endif
                }
                break;
        }

        ehci->caps = hcd->regs;
        ehci->regs = hcd->regs +
                HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));

        dbg_hcs_params(ehci, "reset");
        dbg_hcc_params(ehci, "reset");

        /* ehci_init() causes memory for DMA transfers to be
         * allocated.  Thus, any vendor-specific workarounds based on
         * limiting the type of memory used for DMA transfers must
         * happen before ehci_init() is called. */
        switch (pdev->vendor) {
        case PCI_VENDOR_ID_NVIDIA:
                /* NVidia reports that certain chips don't handle
                 * QH, ITD, or SITD addresses above 2GB.  (But TD,
                 * data buffer, and periodic schedule are normal.)
                 */
                switch (pdev->device) {
                case 0x003c:    /* MCP04 */
                case 0x005b:    /* CK804 */
                case 0x00d8:    /* CK8 */
                case 0x00e8:    /* CK8S */
                        if (pci_set_consistent_dma_mask(pdev,
                                                DMA_BIT_MASK(31)) < 0)
                                ehci_warn(ehci, "can't enable NVidia "
                                        "workaround for >2GB RAM\n");
                        break;
                }
                break;
        }

        /* cache this readonly data; minimize chip reads */
        ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);

        retval = ehci_halt(ehci);
        if (retval)
                return retval;

        if ((pdev->vendor == PCI_VENDOR_ID_AMD && pdev->device == 0x7808) ||
            (pdev->vendor == PCI_VENDOR_ID_ATI && pdev->device == 0x4396)) {
                /* EHCI controller on AMD SB700/SB800/Hudson-2/3 platforms may
                 * read/write memory space which does not belong to it when
                 * there is NULL pointer with T-bit set to 1 in the frame list
                 * table. To avoid the issue, the frame list link pointer
                 * should always contain a valid pointer to a inactive qh.
                 */
                ehci->use_dummy_qh = 1;
                ehci_info(ehci, "applying AMD SB700/SB800/Hudson-2/3 EHCI "
                                "dummy qh workaround\n");
        }

        /* data structure init */
        retval = ehci_init(hcd);
        if (retval)
                return retval;

        switch (pdev->vendor) {
        case PCI_VENDOR_ID_NEC:
                ehci->need_io_watchdog = 0;
                break;
        case PCI_VENDOR_ID_INTEL:
                ehci->need_io_watchdog = 0;
                ehci->fs_i_thresh = 1;
                if (pdev->device == 0x27cc) {
                        ehci->broken_periodic = 1;
                        ehci_info(ehci, "using broken periodic workaround\n");
                }
                if (pdev->device == 0x0806 || pdev->device == 0x0811
                                || pdev->device == 0x0829) {
                        ehci_info(ehci, "disable lpm for langwell/penwell\n");
                        ehci->has_lpm = 0;
                }
                if (pdev->device == PCI_DEVICE_ID_INTEL_CE4100_USB) {
                        hcd->has_tt = 1;
                        tdi_reset(ehci);
                }
                break;
        case PCI_VENDOR_ID_TDI:
                if (pdev->device == PCI_DEVICE_ID_TDI_EHCI) {
                        hcd->has_tt = 1;
                        tdi_reset(ehci);
                }
                break;
        case PCI_VENDOR_ID_AMD:
                /* AMD PLL quirk */
                if (usb_amd_find_chipset_info())
                        ehci->amd_pll_fix = 1;
                /* AMD8111 EHCI doesn't work, according to AMD errata */
                if (pdev->device == 0x7463) {
                        ehci_info(ehci, "ignoring AMD8111 (errata)\n");
                        retval = -EIO;
                        goto done;
                }
                break;
        case PCI_VENDOR_ID_NVIDIA:
                switch (pdev->device) {
                /* Some NForce2 chips have problems with selective suspend;
                 * fixed in newer silicon.
                 */
                case 0x0068:
                        if (pdev->revision < 0xa4)
                                ehci->no_selective_suspend = 1;
                        break;

                /* MCP89 chips on the MacBookAir3,1 give EPROTO when
                 * fetching device descriptors unless LPM is disabled.
                 * There are also intermittent problems enumerating
                 * devices with PPCD enabled.
                 */
                case 0x0d9d:
                        ehci_info(ehci, "disable lpm/ppcd for nvidia mcp89");
                        ehci->has_lpm = 0;
                        ehci->has_ppcd = 0;
                        ehci->command &= ~CMD_PPCEE;
                        break;
                }
                break;
        case PCI_VENDOR_ID_VIA:
                if (pdev->device == 0x3104 && (pdev->revision & 0xf0) == 0x60) {
                        u8 tmp;

                        /* The VT6212 defaults to a 1 usec EHCI sleep time which
                         * hogs the PCI bus *badly*. Setting bit 5 of 0x4B makes
                         * that sleep time use the conventional 10 usec.
                         */
                        pci_read_config_byte(pdev, 0x4b, &tmp);
                        if (tmp & 0x20)
                                break;
                        pci_write_config_byte(pdev, 0x4b, tmp | 0x20);
                }
                break;
        case PCI_VENDOR_ID_ATI:
                /* AMD PLL quirk */
                if (usb_amd_find_chipset_info())
                        ehci->amd_pll_fix = 1;
                /* SB600 and old version of SB700 have a bug in EHCI controller,
                 * which causes usb devices lose response in some cases.
                 */
                if ((pdev->device == 0x4386) || (pdev->device == 0x4396)) {
                        p_smbus = pci_get_device(PCI_VENDOR_ID_ATI,
                                                 PCI_DEVICE_ID_ATI_SBX00_SMBUS,
                                                 NULL);
                        if (!p_smbus)
                                break;
                        rev = p_smbus->revision;
                        if ((pdev->device == 0x4386) || (rev == 0x3a)
                            || (rev == 0x3b)) {
                                u8 tmp;
                                ehci_info(ehci, "applying AMD SB600/SB700 USB "
                                        "freeze workaround\n");
                                pci_read_config_byte(pdev, 0x53, &tmp);
                                pci_write_config_byte(pdev, 0x53, tmp | (1<<3));
                        }
                        pci_dev_put(p_smbus);
                }
                break;
        }

        /* optional debug port, normally in the first BAR */
        temp = pci_find_capability(pdev, 0x0a);
        if (temp) {
                pci_read_config_dword(pdev, temp, &temp);
                temp >>= 16;
                if ((temp & (3 << 13)) == (1 << 13)) {
                        temp &= 0x1fff;
                        ehci->debug = ehci_to_hcd(ehci)->regs + temp;
                        temp = ehci_readl(ehci, &ehci->debug->control);
                        ehci_info(ehci, "debug port %d%s\n",
                                HCS_DEBUG_PORT(ehci->hcs_params),
                                (temp & DBGP_ENABLED)
                                        ? " IN USE"
                                        : "");
                        if (!(temp & DBGP_ENABLED))
                                ehci->debug = NULL;
                }
        }

        ehci_reset(ehci);

        /* at least the Genesys GL880S needs fixup here */
        temp = HCS_N_CC(ehci->hcs_params) * HCS_N_PCC(ehci->hcs_params);
        temp &= 0x0f;
        if (temp && HCS_N_PORTS(ehci->hcs_params) > temp) {
                ehci_dbg(ehci, "bogus port configuration: "
                        "cc=%d x pcc=%d < ports=%d\n",
                        HCS_N_CC(ehci->hcs_params),
                        HCS_N_PCC(ehci->hcs_params),
                        HCS_N_PORTS(ehci->hcs_params));

                switch (pdev->vendor) {
                case 0x17a0:            /* GENESYS */
                        /* GL880S: should be PORTS=2 */
                        temp |= (ehci->hcs_params & ~0xf);
                        ehci->hcs_params = temp;
                        break;
                case PCI_VENDOR_ID_NVIDIA:
                        /* NF4: should be PCC=10 */
                        break;
                }
        }

        /* Serial Bus Release Number is at PCI 0x60 offset */
        pci_read_config_byte(pdev, 0x60, &ehci->sbrn);

        /* Keep this around for a while just in case some EHCI
         * implementation uses legacy PCI PM support.  This test
         * can be removed on 17 Dec 2009 if the dev_warn() hasn't
         * been triggered by then.
         */
        if (!device_can_wakeup(&pdev->dev)) {
                u16     port_wake;

                pci_read_config_word(pdev, 0x62, &port_wake);
                if (port_wake & 0x0001) {
                        dev_warn(&pdev->dev, "Enabling legacy PCI PM\n");
                        device_set_wakeup_capable(&pdev->dev, 1);
                }
        }

#ifdef  CONFIG_USB_SUSPEND
        /* REVISIT: the controller works fine for wakeup iff the root hub
         * itself is "globally" suspended, but usbcore currently doesn't
         * understand such things.
         *
         * System suspend currently expects to be able to suspend the entire
         * device tree, device-at-a-time.  If we failed selective suspend
         * reports, system suspend would fail; so the root hub code must claim
         * success.  That's lying to usbcore, and it matters for runtime
         * PM scenarios with selective suspend and remote wakeup...
         */
        if (ehci->no_selective_suspend && device_can_wakeup(&pdev->dev))
                ehci_warn(ehci, "selective suspend/wakeup unavailable\n");
#endif

        ehci_port_power(ehci, 1);
        retval = ehci_pci_reinit(ehci, pdev);
done:
        return retval;
}

/*-------------------------------------------------------------------------*/

#ifdef  CONFIG_PM

/* suspend/resume, section 4.3 */

/* These routines rely on the PCI bus glue
 * to handle powerdown and wakeup, and currently also on
 * transceivers that don't need any software attention to set up
 * the right sort of wakeup.
 * Also they depend on separate root hub suspend/resume.
 */

static int ehci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
{
        struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
        unsigned long           flags;
        int                     rc = 0;

        if (time_before(jiffies, ehci->next_statechange))
                msleep(10);

        /* Root hub was already suspended. Disable irq emission and
         * mark HW unaccessible.  The PM and USB cores make sure that
         * the root hub is either suspended or stopped.
         */
        ehci_prepare_ports_for_controller_suspend(ehci, do_wakeup);
        spin_lock_irqsave (&ehci->lock, flags);
        ehci_writel(ehci, 0, &ehci->regs->intr_enable);
        (void)ehci_readl(ehci, &ehci->regs->intr_enable);

        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
        spin_unlock_irqrestore (&ehci->lock, flags);

        // could save FLADJ in case of Vaux power loss
        // ... we'd only use it to handle clock skew

        return rc;
}

static bool usb_is_intel_switchable_ehci(struct pci_dev *pdev)
{
        return pdev->class == PCI_CLASS_SERIAL_USB_EHCI &&
                pdev->vendor == PCI_VENDOR_ID_INTEL &&
                pdev->device == 0x1E26;
}

static void ehci_enable_xhci_companion(void)
{
        struct pci_dev          *companion = NULL;

        /* The xHCI and EHCI controllers are not on the same PCI slot */
        for_each_pci_dev(companion) {
                if (!usb_is_intel_switchable_xhci(companion))
                        continue;
                usb_enable_xhci_ports(companion);
                return;
        }
}

static int ehci_pci_resume(struct usb_hcd *hcd, bool hibernated)
{
        struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
        struct pci_dev          *pdev = to_pci_dev(hcd->self.controller);

        /* The BIOS on systems with the Intel Panther Point chipset may or may
         * not support xHCI natively.  That means that during system resume, it
         * may switch the ports back to EHCI so that users can use their
         * keyboard to select a kernel from GRUB after resume from hibernate.
         *
         * The BIOS is supposed to remember whether the OS had xHCI ports
         * enabled before resume, and switch the ports back to xHCI when the
         * BIOS/OS semaphore is written, but we all know we can't trust BIOS
         * writers.
         *
         * Unconditionally switch the ports back to xHCI after a system resume.
         * We can't tell whether the EHCI or xHCI controller will be resumed
         * first, so we have to do the port switchover in both drivers.  Writing
         * a '1' to the port switchover registers should have no effect if the
         * port was already switched over.
         */
        if (usb_is_intel_switchable_ehci(pdev))
                ehci_enable_xhci_companion();

        // maybe restore FLADJ

        if (time_before(jiffies, ehci->next_statechange))
                msleep(100);

        /* Mark hardware accessible again as we are out of D3 state by now */
        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);

        /* If CF is still set and we aren't resuming from hibernation
         * then we maintained PCI Vaux power.
         * Just undo the effect of ehci_pci_suspend().
         */
        if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF &&
                                !hibernated) {
                int     mask = INTR_MASK;

                ehci_prepare_ports_for_controller_resume(ehci);
                if (!hcd->self.root_hub->do_remote_wakeup)
                        mask &= ~STS_PCD;
                ehci_writel(ehci, mask, &ehci->regs->intr_enable);
                ehci_readl(ehci, &ehci->regs->intr_enable);
                return 0;
        }

        usb_root_hub_lost_power(hcd->self.root_hub);

        /* Else reset, to cope with power loss or flush-to-storage
         * style "resume" having let BIOS kick in during reboot.
         */
        (void) ehci_halt(ehci);
        (void) ehci_reset(ehci);
        (void) ehci_pci_reinit(ehci, pdev);

        /* emptying the schedule aborts any urbs */
        spin_lock_irq(&ehci->lock);
        if (ehci->reclaim)
                end_unlink_async(ehci);
        ehci_work(ehci);
        spin_unlock_irq(&ehci->lock);

        ehci_writel(ehci, ehci->command, &ehci->regs->command);
        ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
        ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */

        /* here we "know" root ports should always stay powered */
        ehci_port_power(ehci, 1);

        hcd->state = HC_STATE_SUSPENDED;
        return 0;
}
#endif

static int ehci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
{
        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
        int rc = 0;

        if (!udev->parent) /* udev is root hub itself, impossible */
                rc = -1;
        /* we only support lpm device connected to root hub yet */
        if (ehci->has_lpm && !udev->parent->parent) {
                rc = ehci_lpm_set_da(ehci, udev->devnum, udev->portnum);
                if (!rc)
                        rc = ehci_lpm_check(ehci, udev->portnum);
        }
        return rc;
}

static const struct hc_driver ehci_pci_hc_driver = {
        .description =          hcd_name,
        .product_desc =         "EHCI Host Controller",
        .hcd_priv_size =        sizeof(struct ehci_hcd),

        /*
         * generic hardware linkage
         */
        .irq =                  ehci_irq,
        .flags =                HCD_MEMORY | HCD_USB2,

        /*
         * basic lifecycle operations
         */
        .reset =                ehci_pci_setup,
        .start =                ehci_run,
#ifdef  CONFIG_PM
        .pci_suspend =          ehci_pci_suspend,
        .pci_resume =           ehci_pci_resume,
#endif
        .stop =                 ehci_stop,
        .shutdown =             ehci_shutdown,

        /*
         * managing i/o requests and associated device resources
         */
        .urb_enqueue =          ehci_urb_enqueue,
        .urb_dequeue =          ehci_urb_dequeue,
        .endpoint_disable =     ehci_endpoint_disable,
        .endpoint_reset =       ehci_endpoint_reset,

        /*
         * scheduling support
         */
        .get_frame_number =     ehci_get_frame,

        /*
         * root hub support
         */
        .hub_status_data =      ehci_hub_status_data,
        .hub_control =          ehci_hub_control,
        .bus_suspend =          ehci_bus_suspend,
        .bus_resume =           ehci_bus_resume,
        .relinquish_port =      ehci_relinquish_port,
        .port_handed_over =     ehci_port_handed_over,

        /*
         * call back when device connected and addressed
         */
        .update_device =        ehci_update_device,

        .clear_tt_buffer_complete       = ehci_clear_tt_buffer_complete,
};

/*-------------------------------------------------------------------------*/

/* PCI driver selection metadata; PCI hotplugging uses this */
static const struct pci_device_id pci_ids [] = { {
        /* handle any USB 2.0 EHCI controller */
        PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_EHCI, ~0),
        .driver_data =  (unsigned long) &ehci_pci_hc_driver,
        },
        { /* end: all zeroes */ }
};
MODULE_DEVICE_TABLE(pci, pci_ids);

/* pci driver glue; this is a "new style" PCI driver module */
static struct pci_driver ehci_pci_driver = {
        .name =         (char *) hcd_name,
        .id_table =     pci_ids,

        .probe =        usb_hcd_pci_probe,
        .remove =       usb_hcd_pci_remove,
        .shutdown =     usb_hcd_pci_shutdown,

#ifdef CONFIG_PM_SLEEP
        .driver =       {
                .pm =   &usb_hcd_pci_pm_ops
        },
#endif
};