/* $NetBSD: rk_usb.c,v 1.13 2021/08/07 16:18:45 thorpej Exp $ */

/*-
 * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/cdefs.h>

__KERNEL_RCSID(0, "$NetBSD: rk_usb.c,v 1.13 2021/08/07 16:18:45 thorpej Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kmem.h>

#include <dev/clk/clk_backend.h>

#include <dev/fdt/fdtvar.h>
#include <dev/fdt/syscon.h>

static int rk_usb_match(device_t, cfdata_t, void *);
static void rk_usb_attach(device_t, device_t, void *);

#define RK3328_CON0_REG                 0x100
#define RK3328_CON1_REG                 0x104
#define RK3328_CON2_REG                 0x108
#define  RK3328_USBPHY_COMMONONN        __BIT(4)

#define RK3399_GRF_USB20_PHY0_CON0_REG  0x0e450
#define RK3399_GRF_USB20_PHY1_CON0_REG  0x0e460
#define  RK3399_USBPHY_COMMONONN        __BIT(4)
#define RK3399_GRF_USB20_PHY0_CON1_REG  0x0e454
#define RK3399_GRF_USB20_PHY1_CON1_REG  0x0e464
#define RK3399_GRF_USB20_PHY0_CON2_REG  0x0e458
#define RK3399_GRF_USB20_PHY1_CON2_REG  0x0e468
#define  RK3399_USBPHY_SUSPEND_N        __BIT(1)
#define  RK3399_USBPHY_UTMI_SEL         __BIT(0)

#define RK3399_PHY_NO(_sc)      ((_sc)->sc_reg == 0xe450 ? 0 : 1)

enum rk_usb_type {
        USB_RK3328 = 1,
        USB_RK3399,
};

static const struct device_compatible_entry compat_data[] = {
        { .compat = "rockchip,rk3328-usb2phy",  .value = USB_RK3328 },
        { .compat = "rockchip,rk3399-usb2phy",  .value = USB_RK3399 },
        DEVICE_COMPAT_EOL
};

struct rk_usb_clk {
        struct clk              base;
};

struct rk_usb_softc {
        device_t                sc_dev;
        struct syscon           *sc_syscon;
        enum rk_usb_type        sc_type;

        struct clk_domain       sc_clkdom;
        struct rk_usb_clk       sc_usbclk;

        bus_addr_t              sc_reg;
};

CFATTACH_DECL_NEW(rk_usb, sizeof(struct rk_usb_softc),
        rk_usb_match, rk_usb_attach, NULL, NULL);

static struct clk *
rk_usb_clk_get(void *priv, const char *name)
{
        struct rk_usb_softc * const sc = priv;

        if (strcmp(name, sc->sc_usbclk.base.name) != 0)
                return NULL;

        return &sc->sc_usbclk.base;
}

static void
rk_usb_clk_put(void *priv, struct clk *clk)
{
}

static u_int
rk_usb_clk_get_rate(void *priv, struct clk *clk)
{
        return 480000000;
}

static int
rk_usb_clk_enable(void *priv, struct clk *clk)
{
        struct rk_usb_softc * const sc = priv;
        uint32_t reg, write_mask, write_val;

        switch (sc->sc_type) {
        case USB_RK3328:
                reg = RK3328_CON2_REG;
                write_mask = RK3328_USBPHY_COMMONONN << 16;
                write_val = 0;
                break;
        case USB_RK3399:
                reg = RK3399_PHY_NO(sc) == 0 ?
                    RK3399_GRF_USB20_PHY0_CON0_REG :
                    RK3399_GRF_USB20_PHY1_CON0_REG;
                write_mask = RK3399_USBPHY_COMMONONN << 16;
                write_val = 0;
                break;
        default:
                return ENXIO;
        }

        syscon_lock(sc->sc_syscon);
        syscon_write_4(sc->sc_syscon, reg, write_mask | write_val);
        syscon_unlock(sc->sc_syscon);

        return 0;
}

static int
rk_usb_clk_disable(void *priv, struct clk *clk)
{
        struct rk_usb_softc * const sc = priv;
        uint32_t reg, write_mask, write_val;

        switch (sc->sc_type) {
        case USB_RK3328:
                reg = RK3328_CON2_REG;
                write_mask = RK3328_USBPHY_COMMONONN << 16;
                write_val = RK3328_USBPHY_COMMONONN;
                break;
        case USB_RK3399:
                reg = RK3399_PHY_NO(sc) == 0 ?
                    RK3399_GRF_USB20_PHY0_CON0_REG :
                    RK3399_GRF_USB20_PHY1_CON0_REG;
                write_mask = RK3399_USBPHY_COMMONONN << 16;
                write_val = RK3399_USBPHY_COMMONONN;
                break;
        default:
                return ENXIO;
        }

        syscon_lock(sc->sc_syscon);
        syscon_write_4(sc->sc_syscon, reg, write_mask | write_val);
        syscon_unlock(sc->sc_syscon);

        return 0;
}

static const struct clk_funcs rk_usb_clk_funcs = {
        .get = rk_usb_clk_get,
        .put = rk_usb_clk_put,
        .get_rate = rk_usb_clk_get_rate,
        .enable = rk_usb_clk_enable,
        .disable = rk_usb_clk_disable,
};

static struct clk *
rk_usb_fdt_decode(device_t dev, int cc_phandle, const void *data, size_t len)
{
        struct rk_usb_softc * const sc = device_private(dev);

        if (len != 0)
                return NULL;

        return &sc->sc_usbclk.base;
}

static const struct fdtbus_clock_controller_func rk_usb_fdt_funcs = {
        .decode = rk_usb_fdt_decode
};

static int
rk_usb_match(device_t parent, cfdata_t cf, void *aux)
{
        struct fdt_attach_args * const faa = aux;

        return of_compatible_match(faa->faa_phandle, compat_data);
}

static void
rk_usb_attach(device_t parent, device_t self, void *aux)
{
        struct rk_usb_softc * const sc = device_private(self);
        struct fdt_attach_args * const faa = aux;
        const int phandle = faa->faa_phandle;
        struct clk *clk;
        int child;

        /* Cache the base address of this PHY so we know which instance we are */
        if (fdtbus_get_reg(phandle, 0, &sc->sc_reg, NULL) != 0) {
                aprint_error(": couldn't get registers\n");
                return;
        }

        clk = fdtbus_clock_get(phandle, "phyclk");
        if (clk && clk_enable(clk) != 0) {
                aprint_error(": couldn't enable phy clock\n");
                return;
        }

        sc->sc_dev = self;
        sc->sc_type = of_compatible_lookup(phandle, compat_data)->value;
        sc->sc_syscon = fdtbus_syscon_lookup(OF_parent(phandle));
        if (sc->sc_syscon == NULL) {
                aprint_error(": couldn't get grf syscon\n");
                return;
        }

        const char *clkname = fdtbus_get_string(phandle, "clock-output-names");
        if (clkname == NULL)
                clkname = faa->faa_name;

        sc->sc_clkdom.name = device_xname(self);
        sc->sc_clkdom.funcs = &rk_usb_clk_funcs;
        sc->sc_clkdom.priv = sc;
        sc->sc_usbclk.base.domain = &sc->sc_clkdom;
        sc->sc_usbclk.base.name = kmem_asprintf("%s", clkname);
        clk_attach(&sc->sc_usbclk.base);

        aprint_naive("\n");
        aprint_normal(": USB2 PHY\n");

        fdtbus_register_clock_controller(self, phandle, &rk_usb_fdt_funcs);

        for (child = OF_child(phandle); child; child = OF_peer(child)) {
                if (!fdtbus_status_okay(child))
                        continue;

                struct fdt_attach_args cfaa = *faa;
                cfaa.faa_phandle = child;
                cfaa.faa_name = fdtbus_get_string(child, "name");
                cfaa.faa_quiet = false;

                config_found(self, &cfaa, NULL, CFARGS_NONE);
        }
}

/*
 * USB PHY
 */

static int rk_usbphy_match(device_t, cfdata_t, void *);
static void rk_usbphy_attach(device_t, device_t, void *);

struct rk_usbphy_softc {
        device_t        sc_dev;
        int             sc_phandle;
        struct fdtbus_regulator *sc_supply;
};

CFATTACH_DECL_NEW(rk_usbphy, sizeof(struct rk_usbphy_softc),
        rk_usbphy_match, rk_usbphy_attach, NULL, NULL);

static void *
rk_usbphy_acquire(device_t dev, const void *data, size_t len)
{
        struct rk_usbphy_softc * const sc = device_private(dev);

        if (len != 0)
                return NULL;

        return sc;
}

static void
rk_usbphy_release(device_t dev, void *priv)
{
}

static int
rk_usbphy_otg_enable(device_t dev, void *priv, bool enable)
{
        struct rk_usbphy_softc * const sc = device_private(dev);
        struct rk_usb_softc * const usb_sc = device_private(device_parent(dev));
        uint32_t reg, write_mask, write_val;
        int error;

        switch (usb_sc->sc_type) {
        case USB_RK3328:
                reg = RK3328_CON0_REG;
                write_mask = 0x1ffU << 16;
                write_val = enable ? 0 : 0x1d1;
                break;
        case USB_RK3399:
                reg = RK3399_PHY_NO(usb_sc) == 0 ?
                    RK3399_GRF_USB20_PHY0_CON1_REG :
                    RK3399_GRF_USB20_PHY1_CON1_REG;
                write_mask = (RK3399_USBPHY_SUSPEND_N|RK3399_USBPHY_UTMI_SEL) << 16;
                write_val = enable ? 0 : RK3399_USBPHY_UTMI_SEL;
                break;
        default:
                return ENXIO;
        }

        if (sc->sc_supply) {
                error = enable ? fdtbus_regulator_enable(sc->sc_supply) :
                                 fdtbus_regulator_disable(sc->sc_supply);
                if (error != 0)
                        return error;
        }

        syscon_lock(usb_sc->sc_syscon);
        syscon_write_4(usb_sc->sc_syscon, reg, write_mask | write_val);
        syscon_unlock(usb_sc->sc_syscon);

        return 0;
}

static int
rk_usbphy_host_enable(device_t dev, void *priv, bool enable)
{
        struct rk_usbphy_softc * const sc = device_private(dev);
        struct rk_usb_softc * const usb_sc = device_private(device_parent(dev));
        uint32_t reg, write_mask, write_val;
        int error;

        switch (usb_sc->sc_type) {
        case USB_RK3328:
                reg = RK3328_CON1_REG;
                write_mask = 0x1ffU << 16;
                write_val = enable ? 0 : 0x1d1;
                break;
        case USB_RK3399:
                reg = RK3399_PHY_NO(usb_sc) == 0 ?
                    RK3399_GRF_USB20_PHY0_CON2_REG :
                    RK3399_GRF_USB20_PHY1_CON2_REG;
                write_mask = (RK3399_USBPHY_SUSPEND_N|RK3399_USBPHY_UTMI_SEL) << 16;
                write_val = enable ? 0 : RK3399_USBPHY_UTMI_SEL;
                break;
        default:
                return ENXIO;
        }

        if (sc->sc_supply) {
                error = enable ? fdtbus_regulator_enable(sc->sc_supply) :
                                 fdtbus_regulator_disable(sc->sc_supply);
                if (error != 0)
                        return error;
        }

        syscon_lock(usb_sc->sc_syscon);
        syscon_write_4(usb_sc->sc_syscon, reg, write_mask | write_val);
        syscon_unlock(usb_sc->sc_syscon);

        return 0;
}

const struct fdtbus_phy_controller_func rk_usbphy_otg_funcs = {
        .acquire = rk_usbphy_acquire,
        .release = rk_usbphy_release,
        .enable = rk_usbphy_otg_enable,
};

const struct fdtbus_phy_controller_func rk_usbphy_host_funcs = {
        .acquire = rk_usbphy_acquire,
        .release = rk_usbphy_release,
        .enable = rk_usbphy_host_enable,
};

static int
rk_usbphy_match(device_t parent, cfdata_t cf, void *aux)
{
        struct fdt_attach_args * const faa = aux;
        const int phandle = faa->faa_phandle;
        const char *name = fdtbus_get_string(phandle, "name");

        if (strcmp(name, "otg-port") == 0 || strcmp(name, "host-port") == 0)
                return 1;

        return 0;
}

static void
rk_usbphy_attach(device_t parent, device_t self, void *aux)
{
        struct rk_usbphy_softc * const sc = device_private(self);
        struct fdt_attach_args * const faa = aux;
        const int phandle = faa->faa_phandle;
        const char *name = fdtbus_get_string(phandle, "name");

        sc->sc_dev = self;
        sc->sc_phandle = phandle;
        if (of_hasprop(phandle, "phy-supply")) {
                sc->sc_supply = fdtbus_regulator_acquire(phandle, "phy-supply");
                if (sc->sc_supply == NULL) {
                        aprint_error(": couldn't acquire regulator\n");
                        return;
                }
        }

        aprint_naive("\n");

        if (strcmp(name, "otg-port") == 0) {
                aprint_normal(": USB2 OTG port\n");
                fdtbus_register_phy_controller(self, phandle, &rk_usbphy_otg_funcs);
        } else if (strcmp(name, "host-port") == 0) {
                aprint_normal(": USB2 host port\n");
                fdtbus_register_phy_controller(self, phandle, &rk_usbphy_host_funcs);
        }
}