/* $NetBSD: aupsc.c,v 1.9 2021/08/07 16:18:58 thorpej Exp $ */

/*-
 * Copyright (c) 2006 Shigeyuki Fukushima.
 * All rights reserved.
 *
 * Written by Shigeyuki Fukushima.
 *
 * 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.
 * 3. 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.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: aupsc.c,v 1.9 2021/08/07 16:18:58 thorpej Exp $");

#include "locators.h"

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

#include <sys/bus.h>
#include <machine/cpu.h>

#include <mips/alchemy/include/aubusvar.h>
#include <mips/alchemy/include/aureg.h>
#include <mips/alchemy/dev/aupscreg.h>
#include <mips/alchemy/dev/aupscvar.h>
#include <mips/alchemy/dev/ausmbus_pscreg.h>

struct aupsc_softc {
        device_t                sc_dev;
        bus_space_tag_t         sc_bust;
        bus_space_handle_t      sc_bush;
        int                     sc_pscsel;
};

const struct aupsc_proto {
        const char *name;
        int protocol;
} aupsc_protos [] = {
        { "ausmbus", AUPSC_SEL_SMBUS },
        { "auspi", AUPSC_SEL_SPI },
#if 0
        { "auaudio" },
        { "aui2s" },
#endif
        { NULL, AUPSC_SEL_DISABLE }
};

static int      aupsc_match(device_t, struct cfdata *, void *);
static void     aupsc_attach(device_t, device_t, void *);
static int      aupsc_submatch(device_t, struct cfdata *, const int *, void *);
static int      aupsc_print(void *, const char *);

static void     aupsc_enable(void *, int);
static void     aupsc_disable(void *);
static void     aupsc_suspend(void *);


CFATTACH_DECL_NEW(aupsc, sizeof(struct aupsc_softc),
        aupsc_match, aupsc_attach, NULL, NULL);

static int
aupsc_match(device_t parent, struct cfdata *cf, void *aux)
{
        struct aubus_attach_args *aa = (struct aubus_attach_args *)aux;

        if (strcmp(aa->aa_name, cf->cf_name) != 0)
                return 0;

        return 1;
}

static void
aupsc_attach(device_t parent, device_t self, void *aux)
{
        int i;
        uint32_t rv;
        struct aupsc_softc *sc = device_private(self);
        struct aubus_attach_args *aa = (struct aubus_attach_args *)aux;
        struct aupsc_attach_args pa;
        struct aupsc_controller ctrl;

        sc->sc_dev = self;
        sc->sc_bust = aa->aa_st;
        if (bus_space_map(sc->sc_bust, aa->aa_addr,
                        AUPSC_SIZE, 0, &sc->sc_bush) != 0) {
                aprint_error(": unable to map device registers\n");
                return;
        }

        /* Initialize PSC_SEL register */
        sc->sc_pscsel = AUPSC_SEL_DISABLE;
        rv = bus_space_read_4(sc->sc_bust, sc->sc_bush, AUPSC_SEL);
        bus_space_write_4(sc->sc_bust, sc->sc_bush,
                AUPSC_SEL, (rv & AUPSC_SEL_PS(AUPSC_SEL_DISABLE)));
        bus_space_write_4(sc->sc_bust, sc->sc_bush,
                AUPSC_CTRL, AUPSC_CTRL_ENA(AUPSC_CTRL_DISABLE));

        aprint_normal(": Alchemy PSC\n");
        aprint_naive("\n");

        ctrl.psc_bust = sc->sc_bust;
        ctrl.psc_bush = sc->sc_bush;
        ctrl.psc_sel = &(sc->sc_pscsel);
        ctrl.psc_enable = aupsc_enable;
        ctrl.psc_disable = aupsc_disable;
        ctrl.psc_suspend = aupsc_suspend;
        pa.aupsc_ctrl = ctrl;
        pa.aupsc_addr = aa->aa_addr;
        pa.aupsc_irq = aa->aa_irq[0];

        for (i = 0 ; aupsc_protos[i].name != NULL ; i++) {
                struct aupsc_protocol_device p;
                uint32_t s;

                pa.aupsc_name = aupsc_protos[i].name;

                p.sc_dev = sc->sc_dev;
                p.sc_ctrl = ctrl;

                aupsc_enable(&p, aupsc_protos[i].protocol);
                s = bus_space_read_4(sc->sc_bust, sc->sc_bush, AUPSC_STAT);
                aupsc_disable(&p);

                if (s & AUPSC_STAT_SR) {
                        config_found(self, &pa, aupsc_print,
                            CFARGS(.submatch = aupsc_submatch));
                }
        }
}

static int
aupsc_submatch(device_t parent, struct cfdata *cf, const int *ldesc, void *aux)
{

        return config_match(parent, cf, aux);
}

static int
aupsc_print(void *aux, const char *pnp)
{
        /*
         * By default we don't want to print anything, because
         * otherwise we see complaints about protocols that aren't
         * configured on every port.  (E.g. each PSC can support 4
         * protocols, but on a typical design, only one protocol can
         * be configured per board.)
         *
         * Basically, this whole thing should be replaced with an
         * indirect configuration mechanism.  Direct configuration
         * doesn't make sense when we absolutely require kernel
         * configuration to operate.
         *
         * Alternatively, a board-specific configuration mechanism
         * could determine this, and provide direct configuration as
         * we do for PCMCIA.
         */

        return QUIET;
}

static void
aupsc_enable(void *arg, int proto)
{
        struct aupsc_protocol_device *sc = arg;
        int i;

        /* XXX: (TODO) setting clock AUPSC_SEL_CLK */
        switch (proto) {
        case AUPSC_SEL_SPI:
        case AUPSC_SEL_I2S:
        case AUPSC_SEL_AC97:
        case AUPSC_SEL_SMBUS:
                break;
        case AUPSC_SEL_DISABLE:
                aupsc_disable(arg);
                break;
        default:
                printf("%s: aupsc_enable: unsupported protocol.\n",
                        device_xname(sc->sc_dev));
                return;
        }

        if (*(sc->sc_ctrl.psc_sel) != AUPSC_SEL_DISABLE) {
                printf("%s: aupsc_enable: please disable first.\n",
                        device_xname(sc->sc_dev));
                return;
        }

        bus_space_write_4(sc->sc_ctrl.psc_bust, sc->sc_ctrl.psc_bush,
                        AUPSC_SEL, AUPSC_SEL_PS(proto));
        bus_space_write_4(sc->sc_ctrl.psc_bust, sc->sc_ctrl.psc_bush,
                        AUPSC_CTRL, AUPSC_CTRL_ENA(AUPSC_CTRL_ENABLE));

        /* wait up to a whole second, but test every 10us */
        for (i = 1000000; i; i -= 10) {
                if (bus_space_read_4(sc->sc_ctrl.psc_bust,
                        sc->sc_ctrl.psc_bush, AUPSC_STAT) & AUPSC_STAT_SR)
                        return;
                delay(10);
        }
}

static void
aupsc_disable(void *arg)
{
        struct aupsc_protocol_device *sc = arg;

        bus_space_write_4(sc->sc_ctrl.psc_bust, sc->sc_ctrl.psc_bush,
                        AUPSC_SEL, AUPSC_SEL_PS(AUPSC_SEL_DISABLE));
        bus_space_write_4(sc->sc_ctrl.psc_bust, sc->sc_ctrl.psc_bush,
                        AUPSC_CTRL, AUPSC_CTRL_ENA(AUPSC_CTRL_DISABLE));
        delay(1);
}

static void
aupsc_suspend(void *arg)
{
        struct aupsc_protocol_device *sc = arg;

        bus_space_write_4(sc->sc_ctrl.psc_bust, sc->sc_ctrl.psc_bush,
                        AUPSC_CTRL, AUPSC_CTRL_ENA(AUPSC_CTRL_SUSPEND));
        delay(1);
}