/*      $NetBSD: if_iee_sbdio.c,v 1.13 2020/07/22 01:24:40 msaitoh Exp $        */

/*
 * Copyright (c) 2003 Jochen Kunz.
 * 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.
 * 3. The name of Jochen Kunz may not be used to endorse or promote
 *    products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY JOCHEN KUNZ
 * ``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 JOCHEN KUNZ
 * 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: if_iee_sbdio.c,v 1.13 2020/07/22 01:24:40 msaitoh Exp $");

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/intr.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/systm.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_ether.h>

#include <mips/cache.h>
#include <mips/locore.h>
#include <machine/sbdvar.h>     /* for ether_addr() */
#include <machine/sbdiovar.h>

#include <dev/ic/i82596reg.h>
#include <dev/ic/i82596var.h>

int iee_sbdio_match(device_t, cfdata_t, void *);
void iee_sbdio_attach(device_t, device_t, void *);
int iee_sbdio_cmd(struct iee_softc *, uint32_t);
int iee_sbdio_reset(struct iee_softc *);

static void iee_sbdio_channel_attention(void *);
static void iee_sbdio_chip_reset(void *);
static void iee_sbdio_set_scp(void *, uint32_t);

struct iee_sbdio_softc {
        struct iee_softc sc_iee;
        volatile uint32_t *sc_port;     /* CPU <-> i82596 interface */
};

CFATTACH_DECL_NEW(iee_sbdio, sizeof(struct iee_sbdio_softc),
    iee_sbdio_match, iee_sbdio_attach, NULL, NULL);

int
iee_sbdio_match(device_t parent, cfdata_t cf, void *aux)
{
        struct sbdio_attach_args *sa = aux;

        return strcmp(sa->sa_name, "iee") ? 0 : 1;
}

void
iee_sbdio_attach(device_t parent, device_t self, void *aux)
{
        struct iee_sbdio_softc *sc_ssc = device_private(self);
        struct iee_softc *sc = &sc_ssc->sc_iee;
        struct sbdio_attach_args *sa = aux;
        uint8_t eaddr[ETHER_ADDR_LEN];
        int media[2];

        sc->sc_dev = self;
        sc_ssc->sc_port =
            (volatile uint32_t *)MIPS_PHYS_TO_KSEG1(sa->sa_addr1);
        sc->sc_type = I82596_CA;
        sc->sc_flags = IEE_NEED_SWAP;

        /* bus_dma round the dma size to page size. */
        sc->sc_cl_align = 1;

        sc->sc_dmat = sa->sa_dmat;

        /* Setup SYSBUS byte. TR2 specific? -uch */
        sc->sc_sysbus = IEE_SYSBUS_BE | IEE_SYSBUS_INT |
            IEE_SYSBUS_LIEAR | IEE_SYSBUS_STD;

        sc->sc_iee_reset = iee_sbdio_reset;
        sc->sc_iee_cmd = iee_sbdio_cmd;
        sc->sc_mediachange = NULL;
        sc->sc_mediastatus = NULL;

        media[0] = IFM_ETHER | IFM_MANUAL;
        media[1] = IFM_ETHER | IFM_10_5;

        intr_establish(sa->sa_irq, iee_intr, sc);
        (*platform.ether_addr)(eaddr);
        iee_attach(sc, eaddr, media, 2, IFM_ETHER | IFM_10_5);
}

int
iee_sbdio_cmd(struct iee_softc *sc, uint32_t cmd)
{
        int retry = 8;
        int n;
        uint32_t ack;

        SC_SCB(sc)->scb_cmd = cmd;
        IEE_SCBSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

        iee_sbdio_channel_attention(sc);

        /* Wait for the cmd to finish */
        for (n = 0 ; n < retry; n++) {
                IEE_SCBSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                ack = SC_SCB(sc)->scb_cmd;
                IEE_SCBSYNC(sc, BUS_DMASYNC_PREREAD);
                if (ack == 0)
                        break;
                delay(1);
        }
        if (n < retry)
                return 0;

        printf("%s: command timeout. retry=%d\n",
            device_xname(sc->sc_dev), retry);

        return -1;
}

int
iee_sbdio_reset(struct iee_softc *sc)
{
#define IEE_ISCP_BUSY 0x1
        int n, retry = 8;
        uint32_t cmd, ack;

        /* Make sure the busy byte is set and the cache is flushed. */
        SC_ISCP(sc)->iscp_busy = IEE_ISCP_BUSY;
        IEE_ISCPSYNC(sc, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

        /* Setup the PORT Command with pointer to SCP. */
        cmd = IEE_PORT_SCP | IEE_PHYS_SHMEM(sc->sc_scp_off);

        /* Initiate a Hardware reset. */
        printf("%s: resetting chip... ", device_xname(sc->sc_dev));
        iee_sbdio_chip_reset(sc);

        /* Set SCP address to CU */
        iee_sbdio_set_scp(sc, cmd);

        /* Wait for the chip to initialize and read SCP and ISCP. */
        for (n = 0 ; n < retry; n++) {
                IEE_ISCPSYNC(sc, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
                ack = SC_ISCP(sc)->iscp_busy;
                IEE_ISCPSYNC(sc, BUS_DMASYNC_PREREAD);
                if (ack != IEE_ISCP_BUSY) {
                        break;
                }
                delay(100);
        }

        if (n < retry) {
                /* ACK interrupts we may have caused */
                sc->sc_iee_cmd(sc, IEE_SCB_ACK);
                printf("done.\n");

                return 0;
        }
        printf("time out.\n");

        return -1;
}

static void
iee_sbdio_channel_attention(void *cookie)
{
        struct iee_sbdio_softc *sc = cookie;
        uint32_t dummy;

        /* Issue a Channel Attention */
        dummy = *sc->sc_port;
        dummy = *sc->sc_port;
        __USE(dummy);
}

static void
iee_sbdio_chip_reset(void *cookie)
{
        struct iee_sbdio_softc *sc = cookie;

        *sc->sc_port = 0;
        *sc->sc_port = 0;
        delay(10);
}

static void
iee_sbdio_set_scp(void *cookie, uint32_t cmd)
{
        struct iee_sbdio_softc *sc = cookie;
        cmd = (cmd << 16) | (cmd >> 16);

        *sc->sc_port = cmd;
        *sc->sc_port = cmd;

        /* Issue a Channel Attention to read SCP */
        iee_sbdio_channel_attention(cookie);
}