/*      $NetBSD: if_elmc_mca.c,v 1.33 2022/07/12 02:06:07 thorpej Exp $ */

/*-
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Rafal K. Boni and Jaromir Dolecek.
 *
 * 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.
 */

/*
 * 3Com 3c523 EtherLink/MC Ethernet card driver (uses i82586 Ethernet chip).
 *
 * The 3c523-specific hooks were derived from Linux driver (file
 * drivers/net/3c523.[ch]).
 *
 * This driver uses generic i82586 stuff. See also ai(4), ef(4), ix(4).
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_elmc_mca.c,v 1.33 2022/07/12 02:06:07 thorpej Exp $");

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

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

#include <sys/bus.h>

#include <dev/ic/i82586reg.h>
#include <dev/ic/i82586var.h>
#include <dev/mca/mcadevs.h>
#include <dev/mca/mcavar.h>

#include <dev/mca/3c523reg.h>

struct elmc_mca_softc {
        struct ie_softc sc_ie;

        bus_space_tag_t sc_regt;        /* space tag for registers */
        bus_space_handle_t sc_regh;     /* space handle for registers */

        void            *sc_ih;         /* interrupt handle */
};

int     elmc_mca_match(device_t, cfdata_t, void *);
void    elmc_mca_attach(device_t, device_t, void *);

static void     elmc_mca_copyin(struct ie_softc *, void *, int, size_t);
static void     elmc_mca_copyout(struct ie_softc *, const void *, int, size_t);
static u_int16_t elmc_mca_read_16(struct ie_softc *, int);
static void     elmc_mca_write_16(struct ie_softc *, int, u_int16_t);
static void     elmc_mca_write_24(struct ie_softc *, int, int);
static void     elmc_mca_attn(struct ie_softc *, int);
static void     elmc_mca_hwreset(struct ie_softc *, int);
static int      elmc_mca_intrhook(struct ie_softc *, int);

int
elmc_mca_match(device_t parent, cfdata_t cf,
    void *aux)
{
        struct mca_attach_args *ma = aux;

        switch (ma->ma_id) {
        case MCA_PRODUCT_3C523:
                return 1;
        }

        return 0;
}

void
elmc_mca_attach(device_t parent, device_t self, void *aux)
{
        struct elmc_mca_softc *asc = device_private(self);
        struct ie_softc *sc = &asc->sc_ie;
        struct mca_attach_args *ma = aux;
        int pos2, pos3, i, revision;
        int iobase, irq, pbram_addr;
        bus_space_handle_t ioh, memh;
        u_int8_t myaddr[ETHER_ADDR_LEN];

        pos2 = mca_conf_read(ma->ma_mc, ma->ma_slot, 2);
        pos3 = mca_conf_read(ma->ma_mc, ma->ma_slot, 3);

        /*
         * POS register 2: (adf pos0)
         *
         * 7 6 5 4 3 2 1 0
         *     \ \_/ \_/ \__ enable: 0=adapter disabled, 1=adapter enabled
         *      \  \   \____ I/O Address Range: 00=300-307, 01=1300-1307,
         *       \  \                           10=2300-2307, 11=3300-3307
         *        \  \______ Packet Buffer RAM Address Range:
         *         \            00=0x0c0000-0x0c5fff 01=0x0c8000-0x0cdfff
         *          \           10=0x0d0000-0x0d5fff 11=0x0d8000-0x0ddfff
         *           \______ Transceiver Type: 0=onboard(BNC) 1=ext(DIX)
         *
         * POS register 3: (adf pos1)
         *
         * 7 6 5 4 3 2 1 0
         *          \____/
         *               \__ Interrupt level: 0100=3, 0010=7, 1000=9, 0001=12
         */

        iobase = ELMC_IOADDR_BASE + (0x1000 * ((pos2 & 0x6) >> 1));

        /* get irq */
        switch (pos3 & 0x1f) {
        case 4: irq = 3; break;
        case 2: irq = 7; break;
        case 8: irq = 9; break;
        case 1: irq = 12; break;
        default:
                aprint_error(": cannot determine irq\n");
                return;
        }

        sc->sc_dev = self;
        pbram_addr = ELMC_MADDR_BASE + (((pos2 & 0x18) >> 3) * 0x8000);

        aprint_normal(" slot %d irq %d: 3Com EtherLink/MC Ethernet Adapter "
            "(3C523)\n", ma->ma_slot + 1, irq);

        /* map the pio registers */
        if (bus_space_map(ma->ma_iot, iobase, ELMC_IOADDR_SIZE, 0, &ioh)) {
                aprint_error_dev(self, "unable to map i/o space\n");
                return;
        }

        /*
         * 3c523 has a 24K memory. The first 16K is the shared memory, while
         * the last 8K is for the EtherStart BIOS ROM, which we don't care
         * about. Just use the first 16K.
         */
        if (bus_space_map(ma->ma_memt, pbram_addr, ELMC_MADDR_SIZE, 0, &memh)) {
                aprint_error_dev(self, "unable to map memory space\n");
                if (pbram_addr == 0xc0000) {
                        aprint_error_dev(self,
                            "memory space 0xc0000 may conflict with vga\n");
                }

                bus_space_unmap(ma->ma_iot, ioh, ELMC_IOADDR_SIZE);
                return;
        }

        asc->sc_regt = ma->ma_iot;
        asc->sc_regh = ioh;

        sc->hwinit = NULL;
        sc->intrhook = elmc_mca_intrhook;
        sc->hwreset = elmc_mca_hwreset;
        sc->chan_attn = elmc_mca_attn;

        sc->ie_bus_barrier = NULL;

        sc->memcopyin = elmc_mca_copyin;
        sc->memcopyout = elmc_mca_copyout;
        sc->ie_bus_read16 = elmc_mca_read_16;
        sc->ie_bus_write16 = elmc_mca_write_16;
        sc->ie_bus_write24 = elmc_mca_write_24;

        sc->do_xmitnopchain = 0;

        sc->sc_mediachange = NULL;
        sc->sc_mediastatus = NULL;

        sc->bt = ma->ma_memt;
        sc->bh = memh;

        /* Map i/o space. */
        sc->sc_msize = ELMC_MADDR_SIZE;
        sc->sc_maddr = (void *)memh;
        sc->sc_iobase = (char *)sc->sc_maddr + sc->sc_msize - (1 << 24);

        /* set up pointers to important on-card control structures */
        sc->iscp = 0;
        sc->scb = IE_ISCP_SZ;
        sc->scp = sc->sc_msize + IE_SCP_ADDR - (1 << 24);

        sc->buf_area = sc->scb + IE_SCB_SZ;
        sc->buf_area_sz = sc->sc_msize - IE_ISCP_SZ - IE_SCB_SZ - IE_SCP_SZ;

        /*
         * According to docs, we might need to read the interrupt number and
         * write it back to the IRQ select register, since the POST might not
         * configure the IRQ properly.
         */
        (void) mca_conf_write(ma->ma_mc, ma->ma_slot, 3, pos3 & 0x1f);

        /* reset the card first */
        elmc_mca_hwreset(sc, CARD_RESET);
        delay(1000000 / ( 1<< 5));

        /* zero card memory */
        bus_space_set_region_1(sc->bt, sc->bh, 0, 0, sc->sc_msize);

        /* set card to 16-bit bus mode */
        bus_space_write_1(sc->bt, sc->bh, IE_SCP_BUS_USE((u_long)sc->scp),
                          IE_SYSBUS_16BIT);

        /* set up pointers to key structures */
        elmc_mca_write_24(sc, IE_SCP_ISCP((u_long)sc->scp), (u_long) sc->iscp);
        elmc_mca_write_16(sc, IE_ISCP_SCB((u_long)sc->iscp), (u_long) sc->scb);
        elmc_mca_write_24(sc, IE_ISCP_BASE((u_long)sc->iscp),
            (u_long) sc->iscp);

        /* flush setup of pointers, check if chip answers */
        if (!i82586_proberam(sc)) {
                aprint_error_dev(self, "can't talk to i82586!\n");

                bus_space_unmap(asc->sc_regt, asc->sc_regh, ELMC_IOADDR_SIZE);
                bus_space_unmap(sc->bt, sc->bh, ELMC_MADDR_SIZE);
                return;
        }

        /* revision is stored in the first 4 bits of the revision register */
        revision = (int) bus_space_read_1(asc->sc_regt, asc->sc_regh,
                                ELMC_REVISION) & ELMC_REVISION_MASK;

        /* dump known info */
        aprint_normal("%s: rev %d, i/o %#04x-%#04x, mem %#06x-%#06x, "
            "%sternal xcvr\n",
            device_xname(self), revision,
            iobase, iobase + ELMC_IOADDR_SIZE - 1,
            pbram_addr, pbram_addr + ELMC_MADDR_SIZE - 1,
            (pos2 & 0x20) ? "ex" : "in");

        /*
         * Hardware ethernet address is stored in the first six bytes
         * of the IO space.
         */
        for(i=0; i < MIN(6, ETHER_ADDR_LEN); i++)
                myaddr[i] = bus_space_read_1(asc->sc_regt, asc->sc_regh, i);

        printf("%s:", device_xname(self));
        i82586_attach(sc, "3C523", myaddr, NULL, 0, 0);

        /* establish interrupt handler */
        asc->sc_ih = mca_intr_establish(ma->ma_mc, irq, IPL_NET, i82586_intr,
                        sc);
        if (asc->sc_ih == NULL) {
                aprint_error_dev(self,
                    "couldn't establish interrupt handler\n");
                return;
        }
}

static void
elmc_mca_copyin (struct ie_softc *sc, void *dst, int offset, size_t size)
{
        int dribble;
        u_int8_t* bptr = dst;

        if (offset % 2) {
                *bptr = bus_space_read_1(sc->bt, sc->bh, offset);
                offset++; bptr++; size--;
        }

        dribble = size % 2;
        bus_space_read_region_2(sc->bt, sc->bh, offset, (u_int16_t *) bptr,
                                size >> 1);

        if (dribble) {
                bptr += size - 1;
                offset += size - 1;
                *bptr = bus_space_read_1(sc->bt, sc->bh, offset);
        }
}

static void
elmc_mca_copyout (struct ie_softc *sc, const void *src, int offset,
    size_t size)
{
        int dribble;
        const u_int8_t* bptr = src;

        if (offset % 2) {
                bus_space_write_1(sc->bt, sc->bh, offset, *bptr);
                offset++; bptr++; size--;
        }

        dribble = size % 2;
        bus_space_write_region_2(sc->bt, sc->bh, offset,
            (const u_int16_t *)bptr, size >> 1);
        if (dribble) {
                bptr += size - 1;
                offset += size - 1;
                bus_space_write_1(sc->bt, sc->bh, offset, *bptr);
        }
}

static u_int16_t
elmc_mca_read_16 (struct ie_softc *sc, int offset)
{
        return bus_space_read_2(sc->bt, sc->bh, offset);
}

static void
elmc_mca_write_16 (struct ie_softc *sc, int offset, u_int16_t value)
{
        bus_space_write_2(sc->bt, sc->bh, offset, value);
}

static void
elmc_mca_write_24 (struct ie_softc *sc, int offset, int addr)
{
        bus_space_write_4(sc->bt, sc->bh, offset, addr +
            (u_long) sc->sc_maddr - (u_long) sc->sc_iobase);
}

/*
 * Channel attention hook.
 */
static void
elmc_mca_attn(struct ie_softc *sc, int why)
{
        struct elmc_mca_softc* asc = (struct elmc_mca_softc *) sc;
        int intr = 0;

        switch (why) {
        case CHIP_PROBE:
                intr = 0;
                break;
        case CARD_RESET:
                intr = ELMC_CTRL_INT;
                break;
        }

        bus_space_write_1(asc->sc_regt, asc->sc_regh, ELMC_CTRL,
            ELMC_CTRL_RST | ELMC_CTRL_BS3 | ELMC_CTRL_CHA | intr);
        delay(1);       /* should be > 500 ns */
        bus_space_write_1(asc->sc_regt, asc->sc_regh, ELMC_CTRL,
            ELMC_CTRL_RST | ELMC_CTRL_BS3 | intr);
}

/*
 * Do full card hardware reset.
 */
static void
elmc_mca_hwreset(struct ie_softc *sc, int why)
{
        struct elmc_mca_softc* asc = (struct elmc_mca_softc *) sc;

        /* toggle the RST bit low then high */
        bus_space_write_1(asc->sc_regt, asc->sc_regh, ELMC_CTRL,
            ELMC_CTRL_BS3 | ELMC_CTRL_LOOP);
        delay(1);       /* should be > 500 ns */
        bus_space_write_1(asc->sc_regt, asc->sc_regh, ELMC_CTRL,
            ELMC_CTRL_BS3 | ELMC_CTRL_LOOP | ELMC_CTRL_RST);

        elmc_mca_attn(sc, why);
}

/*
 * Interrupt hook.
 */
static int
elmc_mca_intrhook(struct ie_softc *sc, int why)
{
        switch (why) {
        case INTR_ACK:
                elmc_mca_attn(sc, CHIP_PROBE);
                break;
        default:
                /* do nothing */
                break;
        }

        return (0);
}

CFATTACH_DECL_NEW(elmc_mca, sizeof(struct elmc_mca_softc),
    elmc_mca_match, elmc_mca_attach, NULL, NULL);