/* $NetBSD: tcu.c,v 1.6 2021/08/07 16:19:16 thorpej Exp $ */

/*-
 * Copyright (c) 2016, Felix Deichmann
 * 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 COPYRIGHT HOLDERS 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.
 */

/*
 * flxd TC-USB - TURBOchannel USB host option
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: tcu.c,v 1.6 2021/08/07 16:19:16 thorpej Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/gpio.h>

#include <sys/bus.h>

#include <dev/tc/tcvar.h>

#include <dev/gpio/gpiovar.h>

#include "gpio.h"
#include "slhci_tcu.h"

#define TCU_GPIO_NPINS  8

#define TCU_CPLD_OFFS   0x80
#define TCU_CPLD_SIZE   (4 * 4)

#define TCU_CFG         0x0
#define   TCU_CFG_RUN   __BIT(7)        /* write-only */
#define   TCU_CFG_S1_1  __BIT(3)        /* read-only */
#define   TCU_CFG_S1_2  __BIT(2)        /* read-only */
#define   TCU_CFG_S1_3  __BIT(1)        /* read-only */
#define   TCU_CFG_S1_4  __BIT(0)        /* read-only */
#define TCU_GPIO_DIR    0x4
#define TCU_GPIO_IN     0x8
#define TCU_GPIO_OUT    0xc

struct tcu_softc {
#if NGPIO > 0
        kmutex_t                sc_gpio_mtx;
        struct gpio_chipset_tag sc_gpio_gc;
        gpio_pin_t              sc_gpio_pins[TCU_GPIO_NPINS];
        bus_space_tag_t         sc_gpio_iot;
        bus_space_handle_t      sc_gpio_ioh;
#endif /* NGPIO > 0 */
};

static int  tcu_match(device_t, cfdata_t, void *);
static void tcu_attach(device_t, device_t, void *);

#if NSLHCI_TCU > 0
static int  tcu_print(void *, const char *);
#endif /* NSLHCI_TCU > 0 */
#if NGPIO > 0
static void tcu_gpio_attach(device_t, device_t, void *);
static int  tcu_gpio_read(void *, int);
static void tcu_gpio_write(void *, int, int);
static void tcu_gpio_ctl(void *, int, int);
#endif /* NGPIO > 0 */

CFATTACH_DECL_NEW(tcu, sizeof(struct tcu_softc),
    tcu_match, tcu_attach, NULL, NULL);

static int
tcu_match(device_t parent, cfdata_t cf, void *aux)
{
        struct tc_attach_args *ta = aux;

        if (strncmp("TC-USB  ", ta->ta_modname, TC_ROM_LLEN))
                return 0;

        return 1;
}

static void
tcu_attach(device_t parent, device_t self, void *aux)
{
        struct tc_attach_args *ta = aux;
        bus_space_tag_t iot = ta->ta_memt;
        bus_space_handle_t ioh;
        int error;
        uint8_t cfg;
        char buf[30];

        printf(": TC-USB\n");

        error = bus_space_map(iot, ta->ta_addr + TCU_CPLD_OFFS, TCU_CPLD_SIZE,
            0, &ioh);
        if (error) {
                aprint_error_dev(self, "bus_space_map() failed (%d)\n", error);
                return;
        }

        /*
         * Force reset in case system didn't. SL811 reset pulse and hold time
         * must be min. 16 clocks long (at 48 MHz clock) each.
         */
        bus_space_write_1(iot, ioh, TCU_CFG, 0);
        DELAY(1000);
        bus_space_write_1(iot, ioh, TCU_CFG, TCU_CFG_RUN);
        DELAY(1000);

        cfg = bus_space_read_1(iot, ioh, TCU_CFG);

        bus_space_unmap(iot, ioh, TCU_CPLD_SIZE);

        /* Display DIP switch configuration. */
        (void)snprintb(buf, sizeof(buf),
            "\177\020"
            "b\3S1-1\0"
            "b\2S1-2\0"
            "b\1S1-3\0"
            "b\0S1-4\0"
            "\0", cfg);
        aprint_normal_dev(self, "config %s\n", buf);

        if ((cfg & TCU_CFG_S1_1) != 0 && ta->ta_busspeed != TC_SPEED_12_5_MHZ)
                aprint_error_dev(self, "warning: switch S1-1 asserted with "
                    "clock != 12.5 MHz\n");

#if NSLHCI_TCU > 0
        /* Attach slhci. */
        (void)config_found(self, aux, tcu_print,
            CFARGS(.iattr = "tcu"));
#endif /* NSLHCI_TCU > 0 */
#if NGPIO > 0
        /* Attach gpio(bus). */
        tcu_gpio_attach(parent, self, aux);
#endif /* NGPIO > 0 */
}

#if NSLHCI_TCU > 0
static int
tcu_print(void *aux, const char *pnp)
{

        /* This function is only used for "slhci at tcu". */
        if (pnp)
                aprint_normal("slhci at %s", pnp);

        return UNCONF;
}
#endif /* NSLHCI_TCU > 0 */

#if NGPIO > 0
static void
tcu_gpio_attach(device_t parent, device_t self, void *aux)
{
        struct tcu_softc *sc = device_private(self);
        struct tc_attach_args *ta = aux;
        struct gpiobus_attach_args gba;
        bus_space_tag_t iot = ta->ta_memt;
        uint32_t v;
        int error;

        sc->sc_gpio_iot = iot;

        error = bus_space_map(iot, ta->ta_addr + TCU_CPLD_OFFS, TCU_CPLD_SIZE,
            0, &sc->sc_gpio_ioh);
        if (error) {
                aprint_error_dev(self, "bus_space_map() failed (%d)\n", error);
                return;
        }

        mutex_init(&sc->sc_gpio_mtx, MUTEX_DEFAULT, IPL_NONE);

        v = bus_space_read_4(sc->sc_gpio_iot, sc->sc_gpio_ioh, TCU_GPIO_DIR);

        for (int pin = 0; pin < TCU_GPIO_NPINS; pin++) {
                sc->sc_gpio_pins[pin].pin_num = pin;
                sc->sc_gpio_pins[pin].pin_caps = GPIO_PIN_INPUT |
                    GPIO_PIN_OUTPUT;
                sc->sc_gpio_pins[pin].pin_flags = (v & (UINT32_C(1) << pin)) ?
                    GPIO_PIN_OUTPUT : GPIO_PIN_INPUT;
                sc->sc_gpio_pins[pin].pin_state = tcu_gpio_read(sc, pin);
        }

        sc->sc_gpio_gc.gp_cookie = sc;
        sc->sc_gpio_gc.gp_pin_read = tcu_gpio_read;
        sc->sc_gpio_gc.gp_pin_write = tcu_gpio_write;
        sc->sc_gpio_gc.gp_pin_ctl = tcu_gpio_ctl;

        memset(&gba, 0, sizeof(gba));

        gba.gba_gc = &sc->sc_gpio_gc;
        gba.gba_pins = sc->sc_gpio_pins;
        gba.gba_npins = TCU_GPIO_NPINS;

        config_found(self, &gba, gpiobus_print,
            CFARGS(.iattr = "gpiobus"));
}

static int
tcu_gpio_read(void *arg, int pin)
{
        struct tcu_softc *sc = arg;
        uint32_t v;

        mutex_enter(&sc->sc_gpio_mtx);
        v = bus_space_read_4(sc->sc_gpio_iot, sc->sc_gpio_ioh, TCU_GPIO_IN);
        mutex_exit(&sc->sc_gpio_mtx);

        return (v & (UINT32_C(1) << pin)) ? GPIO_PIN_HIGH : GPIO_PIN_LOW;
}

static void
tcu_gpio_write(void *arg, int pin, int val)
{
        struct tcu_softc *sc = arg;
        uint32_t v;

        mutex_enter(&sc->sc_gpio_mtx);

        v = bus_space_read_4(sc->sc_gpio_iot, sc->sc_gpio_ioh, TCU_GPIO_OUT);

        if (val == GPIO_PIN_LOW)
                v &= ~(UINT32_C(1) << pin);
        else if (val == GPIO_PIN_HIGH)
                v |= (UINT32_C(1) << pin);

        bus_space_write_4(sc->sc_gpio_iot, sc->sc_gpio_ioh, TCU_GPIO_OUT, v);

        mutex_exit(&sc->sc_gpio_mtx);
}

static void
tcu_gpio_ctl(void *arg, int pin, int flags)
{
        struct tcu_softc *sc = arg;
        uint32_t v;

        mutex_enter(&sc->sc_gpio_mtx);

        v = bus_space_read_4(sc->sc_gpio_iot, sc->sc_gpio_ioh, TCU_GPIO_DIR);

        if (flags & GPIO_PIN_INPUT)
                v &= ~(UINT32_C(1) << pin);
        if (flags & GPIO_PIN_OUTPUT)
                v |= (UINT32_C(1) << pin);

        bus_space_write_4(sc->sc_gpio_iot, sc->sc_gpio_ioh, TCU_GPIO_DIR, v);

        mutex_exit(&sc->sc_gpio_mtx);
}
#endif /* NGPIO > 0 */