/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2010-2012 Semihalf
 * Copyright (c) 2012 The FreeBSD Foundation
 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
 * All rights reserved.
 *
 * Portions of this software were developed by Oleksandr Rybalko
 * 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, 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 AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * EHCI driver for Freescale i.MX SoCs which incorporate the USBOH3 controller.
 */

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

#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usb_busdma.h>
#include <dev/usb/usb_process.h>
#include <dev/usb/usb_controller.h>
#include <dev/usb/usb_bus.h>
#include <dev/usb/controller/ehci.h>
#include <dev/usb/controller/ehcireg.h>
#include "usbdevs.h"

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

#include <arm/freescale/imx/imx_ccmvar.h>

#include "opt_platform.h"

/*
 * Notes on the hardware and related FDT data seen in the wild.
 *
 * There are two sets of registers in the USBOH3 implementation; documentation
 * refers to them as "core" and "non-core" registers.  A set of core register
 * exists for each OTG or EHCI device.  There is a single set of non-core
 * registers per USBOH3, and they control aspects of operation not directly
 * related to the USB specs, such as whether interrupts from each of the core
 * devices are able to generate a SoC wakeup event.
 *
 * In the FreeBSD universe we might be inclined to describe the core and
 * non-core registers by using a pair of resource address/size values (two
 * entries in the reg property for each core).  However, we have to work with
 * existing FDT data (which mostly comes from the linux universe), and the way
 * they've chosen to represent this is with an entry for a "usbmisc" device
 * whose reg property describes the non-core registers. The way we handle FDT
 * data, this means that the resources (memory-mapped register range) for the
 * non-core registers belongs to a device other than the echi devices.
 *
 * Because the main ehci device cannot access registers in a range that's
 * defined in the fdt data as belonging to another device, we implement a teeny
 * little "usbmisc" driver which exists only to provide access to the usbmisc
 * control register for each of the 4 usb controller instances.  That little
 * driver is implemented here in this file, before the main driver.
 *
 * In addition to the single usbmisc device, the existing FDT data defines a
 * separate device for each of the OTG or EHCI cores within the USBOH3.  Each of
 * those devices has a set of core registers described by the reg property.
 *
 * The core registers for each of the four cores in the USBOH3 are divided into
 * two parts: a set of imx-specific registers at an offset of 0 from the
 * beginning of the register range, and the standard USB (EHCI or OTG) registers
 * at an offset of 0x100 from the beginning of the register range.  The FreeBSD
 * way of dealing with this might be to map out two ranges in the reg property,
 * but that's not what the alternate universe has done.  To work with existing
 * FDT data, we acquire the resource that maps all the core registers, then use
 * bus_space_subregion() to create another resource that maps just the standard
 * USB registers, which we provide to the standard USB code in the ehci_softc.
 *
 * The following compat strings have been seen for the OTG and EHCI cores.  The
 * FDT compat table in this driver contains all these strings, but as of this
 * writing, not all of these SoCs have been tested with the driver.  The fact
 * that imx27 is common to all of them gives some hope that the driver will work
 * on all these SoCs.
 *   - "fsl,imx23-usb", "fsl,imx27-usb";
 *   - "fsl,imx25-usb", "fsl,imx27-usb";
 *   - "fsl,imx28-usb", "fsl,imx27-usb";
 *   - "fsl,imx51-usb", "fsl,imx27-usb";
 *   - "fsl,imx53-usb", "fsl,imx27-usb";
 *   - "fsl,imx6q-usb", "fsl,imx27-usb";
 *
 * The FDT data for some SoCs contains the following properties, which we don't
 * currently do anything with:
 *   - fsl,usbmisc = <&usbmisc 0>;
 *   - fsl,usbphy = <&usbphy0>;
 *
 * Some imx SoCs have FDT data related to USB PHY, some don't.  We have separate
 * usbphy drivers where needed; this data is mentioned here just to keep all the
 * imx-FDT-usb-related info in one place.  Here are the usbphy compat strings
 * known to exist:
 *   - "nop-usbphy"
 *   - "usb-nop-xceiv";
 *   - "fsl,imx23-usbphy" 
 *   - "fsl,imx28-usbphy", "fsl,imx23-usbphy";
 *   - "fsl,imx6q-usbphy", "fsl,imx23-usbphy";
 *
 */

/*-----------------------------------------------------------------------------
 * imx_usbmisc driver
 *---------------------------------------------------------------------------*/

#define USBNC_OVER_CUR_POL        (1u << 8)
#define USBNC_OVER_CUR_DIS        (1u << 7)

struct imx_usbmisc_softc {
        device_t        dev;
        struct resource *mmio;
};

static struct ofw_compat_data usbmisc_compat_data[] = {
        {"fsl,imx6q-usbmisc",   true},
        {"fsl,imx51-usbmisc",   true},
        {"fsl,imx25-usbmisc",   true},
        {NULL,                  false},
};

static void
imx_usbmisc_set_ctrl(device_t dev, u_int index, uint32_t bits)
{
        struct imx_usbmisc_softc *sc;
        uint32_t reg;

        sc = device_get_softc(dev);
        reg = bus_read_4(sc->mmio, index * sizeof(uint32_t));
        bus_write_4(sc->mmio, index * sizeof(uint32_t), reg | bits);
}

#ifdef notyet
static void
imx_usbmisc_clr_ctrl(device_t dev, u_int index, uint32_t bits)
{
        struct imx_usbmisc_softc *sc;
        uint32_t reg;

        sc = device_get_softc(dev);
        reg = bus_read_4(sc->mmio, index * sizeof(uint32_t));
        bus_write_4(sc->mmio, index * sizeof(uint32_t), reg & ~bits);
}
#endif

static int
imx_usbmisc_probe(device_t dev)
{

        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

        if (ofw_bus_search_compatible(dev, usbmisc_compat_data)->ocd_data) {
                device_set_desc(dev, "i.MX USB Misc Control");
                return (BUS_PROBE_DEFAULT);
        }
        return (ENXIO);
}

static int
imx_usbmisc_detach(device_t dev)
{
        struct imx_usbmisc_softc *sc;

        sc = device_get_softc(dev);

        if (sc->mmio != NULL)
                bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->mmio);

        return (0);
}

static int
imx_usbmisc_attach(device_t dev)
{
        struct imx_usbmisc_softc *sc;
        int rid;

        sc = device_get_softc(dev);

        /* Allocate bus_space resources. */
        rid = 0;
        sc->mmio = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
            RF_ACTIVE);
        if (sc->mmio == NULL) {
                device_printf(dev, "Cannot allocate memory resources\n");
                return (ENXIO);
        }

        OF_device_register_xref(OF_xref_from_node(ofw_bus_get_node(dev)), dev);

        return (0);
}

static device_method_t imx_usbmisc_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,         imx_usbmisc_probe),
        DEVMETHOD(device_attach,        imx_usbmisc_attach),
        DEVMETHOD(device_detach,        imx_usbmisc_detach),

        DEVMETHOD_END
};

static driver_t imx_usbmisc_driver = {
        "imx_usbmisc",
        imx_usbmisc_methods,
        sizeof(struct imx_usbmisc_softc)
};

/*
 * This driver needs to start before the ehci driver, but later than the usual
 * "special" drivers like clocks and cpu.  Ehci starts at DEFAULT so
 * DEFAULT-1000 seems good.
 */
EARLY_DRIVER_MODULE(imx_usbmisc, simplebus, imx_usbmisc_driver,
    0, 0, BUS_PASS_DEFAULT - 1000);

/*-----------------------------------------------------------------------------
 * imx_ehci driver...
 *---------------------------------------------------------------------------*/

/*
 * Each EHCI device in the SoC has some SoC-specific per-device registers at an
 * offset of 0, then the standard EHCI registers begin at an offset of 0x100.
 */
#define IMX_EHCI_REG_OFF        0x100
#define IMX_EHCI_REG_SIZE       0x100

struct imx_ehci_softc {
        ehci_softc_t    ehci_softc;
        device_t        dev;
        struct resource *ehci_mem_res;  /* EHCI core regs. */
        struct resource *ehci_irq_res;  /* EHCI core IRQ. */ 
};

static struct ofw_compat_data compat_data[] = {
        {"fsl,imx6q-usb",       1},
        {"fsl,imx53-usb",       1},
        {"fsl,imx51-usb",       1},
        {"fsl,imx28-usb",       1},
        {"fsl,imx27-usb",       1},
        {"fsl,imx25-usb",       1},
        {"fsl,imx23-usb",       1},
        {NULL,                  0},
};

static void
imx_ehci_post_reset(struct ehci_softc *ehci_softc)
{
        uint32_t usbmode;

        /* Force HOST mode */
        usbmode = EOREAD4(ehci_softc, EHCI_USBMODE_NOLPM);
        usbmode &= ~EHCI_UM_CM;
        usbmode |= EHCI_UM_CM_HOST;
        EOWRITE4(ehci_softc, EHCI_USBMODE_NOLPM, usbmode);
}

static int
imx_ehci_probe(device_t dev)
{

        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

        if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
                device_set_desc(dev, "Freescale i.MX integrated USB controller");
                return (BUS_PROBE_DEFAULT);
        }
        return (ENXIO);
}

static int
imx_ehci_detach(device_t dev)
{
        struct imx_ehci_softc *sc;
        ehci_softc_t *esc;
        int err;

        sc = device_get_softc(dev);

        esc = &sc->ehci_softc;

        /* First detach all children; we can't detach if that fails. */
        if ((err = bus_generic_detach(dev)) != 0)
                return (err);

        if (esc->sc_flags & EHCI_SCFLG_DONEINIT)
                ehci_detach(esc);
        if (esc->sc_intr_hdl != NULL)
                bus_teardown_intr(dev, esc->sc_irq_res, 
                    esc->sc_intr_hdl);
        if (sc->ehci_irq_res != NULL)
                bus_release_resource(dev, SYS_RES_IRQ, 0, 
                    sc->ehci_irq_res);
        if (sc->ehci_mem_res != NULL)
                bus_release_resource(dev, SYS_RES_MEMORY, 0,
                    sc->ehci_mem_res);

        usb_bus_mem_free_all(&esc->sc_bus, &ehci_iterate_hw_softc);

        return (0);
}

static void
imx_ehci_disable_oc(struct imx_ehci_softc *sc)
{
        device_t usbmdev;
        pcell_t usbmprops[2];
        phandle_t node;
        ssize_t size;
        int index;

        /* Get the reference to the usbmisc driver from the fdt data */
        node = ofw_bus_get_node(sc->dev);
        size = OF_getencprop(node, "fsl,usbmisc", usbmprops,
            sizeof(usbmprops));
        if (size < sizeof(usbmprops)) {
                device_printf(sc->dev, "failed to retrieve fsl,usbmisc "
                   "property, cannot disable overcurrent protection");
                return;
        }
        /* Retrieve the device_t via the xref handle. */
        usbmdev = OF_device_from_xref(usbmprops[0]);
        if (usbmdev == NULL) {
                device_printf(sc->dev, "usbmisc device not found, "
                    "cannot disable overcurrent protection");
                return;
        }
        /* Call the device routine to set the overcurrent disable bit. */
        index = usbmprops[1];
        imx_usbmisc_set_ctrl(usbmdev, index, USBNC_OVER_CUR_DIS);
}

static int
imx_ehci_attach(device_t dev)
{
        struct imx_ehci_softc *sc;
        ehci_softc_t *esc;
        int err, rid;

        sc = device_get_softc(dev);
        sc->dev = dev;
        esc = &sc->ehci_softc;
        err = 0;

        /* Allocate bus_space resources. */
        rid = 0;
        sc->ehci_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
            RF_ACTIVE);
        if (sc->ehci_mem_res == NULL) {
                device_printf(dev, "Cannot allocate memory resources\n");
                err = ENXIO;
                goto out;
        }

        rid = 0;
        sc->ehci_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
            RF_ACTIVE);
        if (sc->ehci_irq_res == NULL) {
                device_printf(dev, "Cannot allocate IRQ resources\n");
                err = ENXIO;
                goto out;
        }

        esc->sc_io_tag = rman_get_bustag(sc->ehci_mem_res);
        esc->sc_bus.parent = dev;
        esc->sc_bus.devices = esc->sc_devices;
        esc->sc_bus.devices_max = EHCI_MAX_DEVICES;
        esc->sc_bus.dma_bits = 32;

        /* allocate all DMA memory */
        if (usb_bus_mem_alloc_all(&esc->sc_bus, USB_GET_DMA_TAG(dev),
            &ehci_iterate_hw_softc) != 0) {
                device_printf(dev, "usb_bus_mem_alloc_all() failed\n");
                err = ENOMEM;
                goto out;
        }

        /*
         * Set handle to USB related registers subregion used by
         * generic EHCI driver.
         */
        err = bus_space_subregion(esc->sc_io_tag, 
            rman_get_bushandle(sc->ehci_mem_res),
            IMX_EHCI_REG_OFF, IMX_EHCI_REG_SIZE, &esc->sc_io_hdl);
        if (err != 0) {
                device_printf(dev, "bus_space_subregion() failed\n");
                err = ENXIO;
                goto out;
        }

        /* Setup interrupt handler. */
        err = bus_setup_intr(dev, sc->ehci_irq_res, INTR_TYPE_BIO | INTR_MPSAFE,
            NULL, (driver_intr_t *)ehci_interrupt, esc, &esc->sc_intr_hdl);
        if (err != 0) {
                device_printf(dev, "Could not setup IRQ\n");
                goto out;
        }

        /* Turn on clocks. */
        imx_ccm_usb_enable(dev);

        /* Disable overcurrent detection, if configured to do so. */
        if (OF_hasprop(ofw_bus_get_node(sc->dev), "disable-over-current"))
                imx_ehci_disable_oc(sc);

        /* Add USB bus device. */
        esc->sc_bus.bdev = device_add_child(dev, "usbus", DEVICE_UNIT_ANY);
        if (esc->sc_bus.bdev == NULL) {
                device_printf(dev, "Could not add USB device\n");
                goto out;
        }
        device_set_ivars(esc->sc_bus.bdev, &esc->sc_bus);

        esc->sc_id_vendor = USB_VENDOR_FREESCALE;
        strlcpy(esc->sc_vendor, "Freescale", sizeof(esc->sc_vendor));

        /*
         * Set flags that affect ehci_init() behavior, and hook our post-reset
         * code into the standard controller code.
         */
        esc->sc_flags |= EHCI_SCFLG_NORESTERM | EHCI_SCFLG_TT;
        esc->sc_vendor_post_reset = imx_ehci_post_reset;
        esc->sc_vendor_get_port_speed = ehci_get_port_speed_portsc;

        err = ehci_init(esc);
        if (err != 0) {
                device_printf(dev, "USB init failed, usb_err_t=%d\n", 
                    err);
                goto out;
        }
        esc->sc_flags |= EHCI_SCFLG_DONEINIT;

        /* Probe the bus. */
        err = device_probe_and_attach(esc->sc_bus.bdev);
        if (err != 0) {
                device_printf(dev,
                    "device_probe_and_attach() failed\n");
                goto out;
        }

        err = 0;

out:

        if (err != 0)
                imx_ehci_detach(dev);

        return (err);
}

static device_method_t ehci_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe, imx_ehci_probe),
        DEVMETHOD(device_attach, imx_ehci_attach),
        DEVMETHOD(device_detach, imx_ehci_detach),
        DEVMETHOD(device_suspend, bus_generic_suspend),
        DEVMETHOD(device_resume, bus_generic_resume),
        DEVMETHOD(device_shutdown, bus_generic_shutdown),

        /* Bus interface */
        DEVMETHOD(bus_print_child, bus_generic_print_child),

        DEVMETHOD_END
};

static driver_t ehci_driver = {
        "ehci",
        ehci_methods,
        sizeof(struct imx_ehci_softc)
};

DRIVER_MODULE(imx_ehci, simplebus, ehci_driver, 0, 0);
MODULE_DEPEND(imx_ehci, usb, 1, 1, 1);