/*      $NetBSD: if_le_vme.c,v 1.35 2023/01/06 10:28:28 tsutsui Exp $   */

/*-
* Copyright (c) 1998 maximum entropy.  All rights reserved.
* Copyright (c) 1997 Leo Weppelman.  All rights reserved.
* Copyright (c) 1992, 1993
*      The Regents of the University of California.  All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Ralph Campbell and Rick Macklem.
*
* 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. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
*      @(#)if_le.c     8.2 (Berkeley) 11/16/93
*/

/*-
* Copyright (c) 1995 Charles M. Hannum.  All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Ralph Campbell and Rick Macklem.
*
* 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. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
*      @(#)if_le.c     8.2 (Berkeley) 11/16/93
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_le_vme.c,v 1.35 2023/01/06 10:28:28 tsutsui Exp $");

#include "opt_inet.h"

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

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

#ifdef INET
#include <netinet/in.h>
#include <netinet/if_inarp.h>
#endif

#include <machine/cpu.h>
#include <sys/bus.h>
#include <machine/iomap.h>
#include <machine/scu.h>
#include <machine/intr.h>

#include <atari/atari/device.h>

#include <dev/ic/lancereg.h>
#include <dev/ic/lancevar.h>
#include <dev/ic/am7990reg.h>
#include <dev/ic/am7990var.h>

#include <atari/vme/vmevar.h>
#include <atari/vme/if_levar.h>

/*
* All cards except BVME410 have 64KB RAM. However,
*  - On the Riebl cards the area between the offsets 0xee70-0xeec0 is used
*    to store config data.
*  - On PAM and ROTHRON, mem_addr cannot be mapped if reg_addr is already
*    mapped because they are overwrapped. Just use 32KB as Linux does.
*/
static struct le_addresses {
       u_long  reg_addr;
       u_long  mem_addr;
       int     irq;
       int     reg_size;
       int     mem_size;
       int     type_hint;
} lestd[] = {
       { 0xfe00fff0, 0xfe010000, IRQUNK, 16, 64*1024,
                               LE_OLD_RIEBL|LE_NEW_RIEBL }, /* Riebl   */
       { 0xfecffff0, 0xfecf0000,      5, 16, 32*1024,
                               LE_PAM },                    /* PAM     */
       { 0xfecffff0, 0xfecf0000,      5, 16, 32*1024,
                               LE_ROTHRON },                /* Rhotron */
       { 0xfeff4100, 0xfe000000,      4,  8, VMECF_MEMSIZ_DEFAULT,
                               LE_BVME410 }                 /* BVME410 */
};

#define NLESTD  __arraycount(lestd)

/*
* Default mac for RIEBL cards without a (working) battery. The first 4 bytes
* are the manufacturer id.
*/
static const uint8_t riebl_def_mac[] = {
       0x00, 0x00, 0x36, 0x04, 0x00, 0x00
};

static int le_intr(struct le_softc *, int);
static void lepseudointr(struct le_softc *, void *);
static int le_vme_match(device_t, cfdata_t, void *);
static void le_vme_attach(device_t, device_t, void *);
static int probe_addresses(bus_space_tag_t *, bus_space_tag_t *,
                          bus_space_handle_t *, bus_space_handle_t *);
static void riebl_skip_reserved_area(struct lance_softc *);
static int nm93c06_read(bus_space_tag_t, bus_space_handle_t, int);
static int bvme410_probe(bus_space_tag_t, bus_space_handle_t);
static int bvme410_mem_size(bus_space_tag_t, u_long);
static void bvme410_copytobuf(struct lance_softc *, void *, int, int);
static void bvme410_zerobuf(struct lance_softc *, int, int);

CFATTACH_DECL_NEW(le_vme, sizeof(struct le_softc),
   le_vme_match, le_vme_attach, NULL, NULL);

#if defined(_KERNEL_OPT)
#include "opt_ddb.h"
#endif

static void lewrcsr(struct lance_softc *, uint16_t, uint16_t);
static uint16_t lerdcsr(struct lance_softc *, uint16_t);

static void
lewrcsr(struct lance_softc *sc, uint16_t port, uint16_t val)
{
       struct le_softc *lesc = (struct le_softc *)sc;
       int s;

       s = splhigh();
       bus_space_write_2(lesc->sc_iot, lesc->sc_ioh, LER_RAP, port);
       bus_space_write_2(lesc->sc_iot, lesc->sc_ioh, LER_RDP, val);
       splx(s);
}

static uint16_t
lerdcsr(struct lance_softc *sc, uint16_t port)
{
       struct le_softc *lesc = (struct le_softc *)sc;
       uint16_t val;
       int s;

       s = splhigh();
       bus_space_write_2(lesc->sc_iot, lesc->sc_ioh, LER_RAP, port);
       val = bus_space_read_2(lesc->sc_iot, lesc->sc_ioh, LER_RDP);
       splx(s);

       return val;
}

static int
le_vme_match(device_t parent, cfdata_t cfp, void *aux)
{
       struct vme_attach_args *va = aux;
       int i;
       bus_space_tag_t iot, memt;
       bus_space_handle_t ioh, memh;

       iot  = va->va_iot;
       memt = va->va_memt;

       for (i = 0; i < NLESTD; i++) {
               struct le_addresses *le_ap = &lestd[i];
               int found;

               if ((va->va_iobase != IOBASEUNK)
                    && (va->va_iobase != le_ap->reg_addr))
                       continue;

               if ((va->va_maddr != MADDRUNK)
                    && (va->va_maddr != le_ap->mem_addr))
                       continue;

               if ((le_ap->irq != IRQUNK) && (va->va_irq != le_ap->irq))
                       continue;

               if (bus_space_map(iot, le_ap->reg_addr, le_ap->reg_size, 0,
                   &ioh)) {
                       continue;
               }
               if (le_ap->mem_size == VMECF_MEMSIZ_DEFAULT) {
                       if (bvme410_probe(iot, ioh)) {
                               bus_space_write_2(iot, ioh,
                                   BVME410_BAR, 0x1); /* XXX */
                               le_ap->mem_size =
                                   bvme410_mem_size(memt, le_ap->mem_addr);
                       }
               }
               if (le_ap->mem_size == VMECF_MEMSIZ_DEFAULT) {
                       bus_space_unmap(iot, ioh, le_ap->reg_size);
                       continue;
               }

               if (bus_space_map(memt, le_ap->mem_addr, le_ap->mem_size, 0,
                   &memh)) {
                       bus_space_unmap(iot, ioh, le_ap->reg_size);
                       continue;
               }
               found = probe_addresses(&iot, &memt, &ioh, &memh);
               bus_space_unmap(iot, ioh, le_ap->reg_size);
               bus_space_unmap(memt, memh, le_ap->mem_size);

               if (found) {
                       va->va_iobase = le_ap->reg_addr;
                       va->va_iosize = le_ap->reg_size;
                       va->va_maddr  = le_ap->mem_addr;
                       va->va_msize  = le_ap->mem_size;
                       va->va_aux    = le_ap;
                       if (va->va_irq == IRQUNK)
                               va->va_irq = le_ap->irq;
                       return 1;
               }
       }
       return 0;
}

static int
probe_addresses(bus_space_tag_t *iot, bus_space_tag_t *memt,
   bus_space_handle_t *ioh, bus_space_handle_t *memh)
{

       /*
        * Test accesibility of register and memory area
        */
       if (!bus_space_peek_2(*iot, *ioh, LER_RDP))
               return 0;
       if (!bus_space_peek_1(*memt, *memh, 0))
               return 0;

       /*
        * Test for writable memory
        */
       bus_space_write_2(*memt, *memh, 0, 0xa5a5);
       if (bus_space_read_2(*memt, *memh, 0) != 0xa5a5)
               return 0;

       /*
        * Test writability of selector port.
        */
       bus_space_write_2(*iot, *ioh, LER_RAP, LE_CSR1);
       if (bus_space_read_2(*iot, *ioh, LER_RAP) != LE_CSR1)
               return 0;

       /*
        * Do a small register test
        */
       bus_space_write_2(*iot, *ioh, LER_RAP, LE_CSR0);
       bus_space_write_2(*iot, *ioh, LER_RDP, LE_C0_INIT | LE_C0_STOP);
       if (bus_space_read_2(*iot, *ioh, LER_RDP) != LE_C0_STOP)
               return 0;

       bus_space_write_2(*iot, *ioh, LER_RDP, LE_C0_STOP);
       if (bus_space_read_2(*iot, *ioh, LER_RDP) != LE_C0_STOP)
               return 0;

       return 1;
}

/*
* Interrupt mess. Because the card's interrupt is hardwired to either
* ipl5 or ipl3 (mostly on ipl5) and raising splnet to spl5() just won't do
* (it kills the serial at the least), we use a 2-level interrupt scheme. The
* card interrupt is routed to 'le_intr'. If the previous ipl was below
* splnet, just call the mi-function. If not, save the interrupt status,
* turn off card interrupts (the card is *very* persistent) and arrange
* for a softint 'callback' through 'lepseudointr'.
*/
static int
le_intr(struct le_softc *lesc, int sr)
{
       struct lance_softc *sc = &lesc->sc_am7990.lsc;
       uint16_t csr0;

       if ((sr & PSL_IPL) < (ipl2psl_table[IPL_NET] & PSL_IPL))
               am7990_intr(sc);
       else {
               sc->sc_saved_csr0 = csr0 = lerdcsr(sc, LE_CSR0);
               lewrcsr(sc, LE_CSR0, csr0 & ~LE_C0_INEA);
               add_sicallback((si_farg)lepseudointr, lesc, sc);
       }
       return 1;
}


static void
lepseudointr(struct le_softc *lesc, void *sc)
{
       int s;

       s = splx(lesc->sc_splval);
       am7990_intr(sc);
       splx(s);
}

static void
le_vme_attach(device_t parent, device_t self, void *aux)
{
       struct le_softc *lesc = device_private(self);
       struct lance_softc *sc = &lesc->sc_am7990.lsc;
       struct vme_attach_args *va = aux;
       bus_space_tag_t iot, memt;
       bus_space_handle_t ioh, memh;
       struct le_addresses *le_ap;
       int i;

       sc->sc_dev = self;
       aprint_normal("\n%s: ", device_xname(self));

       iot  = va->va_iot;
       memt = va->va_memt;
       if (bus_space_map(iot, va->va_iobase, va->va_iosize, 0, &ioh))
               panic("%s: cannot map io-area", __func__);
       if (bus_space_map(memt, va->va_maddr, va->va_msize, 0, &memh))
               panic("%s: cannot map mem-area", __func__);

       lesc->sc_iot    = iot;
       lesc->sc_ioh    = ioh;
       lesc->sc_memt   = memt;
       lesc->sc_memh   = memh;
       lesc->sc_splval = (va->va_irq << 8) | PSL_S; /* XXX */
       le_ap           = (struct le_addresses *)va->va_aux;

       /*
        * Go on to find board type
        */
       if ((le_ap->type_hint & LE_PAM) != 0 &&
           bus_space_peek_1(iot, ioh, LER_EEPROM)) {
               aprint_normal("PAM card");
               lesc->sc_type = LE_PAM;
               bus_space_read_1(iot, ioh, LER_MEME);
       } else if ((le_ap->type_hint & LE_BVME410) != 0 &&
           bvme410_probe(iot, ioh)) {
               aprint_normal("BVME410");
               lesc->sc_type = LE_BVME410;
       } else if ((le_ap->type_hint & (LE_NEW_RIEBL|LE_OLD_RIEBL)) != 0) {
               aprint_normal("Riebl card");
               if (bus_space_read_4(memt, memh, RIEBL_MAGIC_ADDR) ==
                   RIEBL_MAGIC)
                       lesc->sc_type = LE_NEW_RIEBL;
               else {
                       aprint_normal("(without battery) ");
                       lesc->sc_type = LE_OLD_RIEBL;
               }
       } else {
               aprint_error("Unsupported card!\n");
               return;
       }

       switch (lesc->sc_type) {
       case LE_BVME410:
               sc->sc_copytodesc   = bvme410_copytobuf;
               sc->sc_copyfromdesc = lance_copyfrombuf_contig;
               sc->sc_copytobuf    = bvme410_copytobuf;
               sc->sc_copyfrombuf  = lance_copyfrombuf_contig;
               sc->sc_zerobuf      = bvme410_zerobuf;
               break;
       default:
               sc->sc_copytodesc   = lance_copytobuf_contig;
               sc->sc_copyfromdesc = lance_copyfrombuf_contig;
               sc->sc_copytobuf    = lance_copytobuf_contig;
               sc->sc_copyfrombuf  = lance_copyfrombuf_contig;
               sc->sc_zerobuf      = lance_zerobuf_contig;
               break;
       }

       sc->sc_rdcsr   = lerdcsr;
       sc->sc_wrcsr   = lewrcsr;
       sc->sc_hwinit  = NULL;
       sc->sc_conf3   = LE_C3_BSWP;
       sc->sc_addr    = 0;
       sc->sc_memsize = va->va_msize;
       sc->sc_mem     = (void *)memh; /* XXX */

       /*
        * Get MAC address
        */
       switch (lesc->sc_type) {
       case LE_OLD_RIEBL:
               memcpy(sc->sc_enaddr, riebl_def_mac, sizeof(sc->sc_enaddr));
               break;
       case LE_NEW_RIEBL:
               for (i = 0; i < sizeof(sc->sc_enaddr); i++)
                       sc->sc_enaddr[i] =
                           bus_space_read_1(memt, memh, i + RIEBL_MAC_ADDR);
               break;
       case LE_PAM:
               i = bus_space_read_1(iot, ioh, LER_EEPROM);
               for (i = 0; i < sizeof(sc->sc_enaddr); i++) {
                       sc->sc_enaddr[i] =
                           (bus_space_read_2(memt, memh, 2 * i) << 4) |
                           (bus_space_read_2(memt, memh, 2 * i + 1) & 0xf);
               }
               i = bus_space_read_1(iot, ioh, LER_MEME);
               break;
       case LE_BVME410:
               for (i = 0; i < (sizeof(sc->sc_enaddr) >> 1); i++) {
                       uint16_t tmp;

                       tmp = nm93c06_read(iot, ioh, i);
                       sc->sc_enaddr[2 * i] = (tmp >> 8) & 0xff;
                       sc->sc_enaddr[2 * i + 1] = tmp & 0xff;
               }
               bus_space_write_2(iot, ioh, BVME410_BAR, 0x1); /* XXX */
       }

       am7990_config(&lesc->sc_am7990);

       if ((lesc->sc_type == LE_OLD_RIEBL) || (lesc->sc_type == LE_NEW_RIEBL))
               riebl_skip_reserved_area(sc);

       /*
        * XXX: We always use uservector 64....
        */
       if ((lesc->sc_intr = intr_establish(64, USER_VEC, 0,
           (hw_ifun_t)le_intr, lesc)) == NULL) {
               aprint_error("le_vme_attach: Can't establish interrupt\n");
               return;
       }

       /*
        * Notify the card of the vector
        */
       switch (lesc->sc_type) {
       case LE_OLD_RIEBL:
       case LE_NEW_RIEBL:
               bus_space_write_2(memt, memh, RIEBL_IVEC_ADDR, 64 + 64);
               break;
       case LE_PAM:
               bus_space_write_1(iot, ioh, LER_IVEC, 64 + 64);
               break;
       case LE_BVME410:
               bus_space_write_2(iot, ioh, BVME410_IVEC, 64 + 64);
               break;
       }

       /*
        * Unmask the VME-interrupt we're on
        */
       if ((machineid & ATARI_TT) != 0)
               SCU->vme_mask |= 1 << va->va_irq;
}

/*
* True if 'addr' containe within [start,len]
*/
#define WITHIN(start, len, addr)        \
               ((addr >= start) && ((addr) <= ((start) + (len))))
static void
riebl_skip_reserved_area(struct lance_softc *sc)
{
       int offset = 0;
       int i;

       for (i = 0; i < sc->sc_nrbuf; i++) {
               if (WITHIN(sc->sc_rbufaddr[i], LEBLEN, RIEBL_RES_START) ||
                   WITHIN(sc->sc_rbufaddr[i], LEBLEN, RIEBL_RES_END)) {
                       offset = RIEBL_RES_END - sc->sc_rbufaddr[i];
               }
               sc->sc_rbufaddr[i] += offset;
       }

       for (i = 0; i < sc->sc_ntbuf; i++) {
               if (WITHIN(sc->sc_tbufaddr[i], LEBLEN, RIEBL_RES_START) ||
                   WITHIN(sc->sc_tbufaddr[i], LEBLEN, RIEBL_RES_END)) {
                       offset = RIEBL_RES_END - sc->sc_tbufaddr[i];
               }
               sc->sc_tbufaddr[i] += offset;
       }
}

static int
nm93c06_read(bus_space_tag_t iot, bus_space_handle_t ioh, int nm93c06reg)
{
       int bar;
       int shift;
       int bits = 0x180 | (nm93c06reg & 0xf);
       int data = 0;

       bar = 1 << BVME410_CS_SHIFT;
       bus_space_write_2(iot, ioh, BVME410_BAR, bar);
       delay(1); /* tCSS = 1 us */
       for (shift = 9; shift >= 0; shift--) {
               if (((bits >> shift) & 1) == 1)
                       bar |= 1 << BVME410_DIN_SHIFT;
               else
                       bar &= ~(1 << BVME410_DIN_SHIFT);
               bus_space_write_2(iot, ioh, BVME410_BAR, bar);
               delay(1); /* tDIS = 0.4 us */
               bar |= 1 << BVME410_CLK_SHIFT;
               bus_space_write_2(iot, ioh, BVME410_BAR, bar);
               delay(2); /* tSKH = 1 us, tSKH + tSKL >= 4 us */
               bar &= ~(1 << BVME410_CLK_SHIFT);
               bus_space_write_2(iot, ioh, BVME410_BAR, bar);
               delay(2); /* tSKL = 1 us, tSKH + tSKL >= 4 us */
       }
       bar &= ~(1 << BVME410_DIN_SHIFT);
       for (shift = 15; shift >= 0; shift--) {
               delay(1); /* tDIS = 100 ns, BVM manual says 0.4 us */
               bar |= 1 << BVME410_CLK_SHIFT;
               bus_space_write_2(iot, ioh, BVME410_BAR, bar);
               delay(2); /* tSKH = 1 us, tSKH + tSKL >= 4 us */
               data |= (bus_space_read_2(iot, ioh, BVME410_BAR) & 1) << shift;
               bar &= ~(1 << BVME410_CLK_SHIFT);
               bus_space_write_2(iot, ioh, BVME410_BAR, bar);
               delay(2); /* tSKL = 1 us, tSKH + tSKL >= 4 us */
       }
       bar &= ~(1 << BVME410_CS_SHIFT);
       bus_space_write_2(iot, ioh, BVME410_BAR, bar);
       delay(1); /* tCS = 1 us */
       return data;
}

static int
bvme410_probe(bus_space_tag_t iot, bus_space_handle_t ioh)
{

       if (!bus_space_peek_2(iot, ioh, BVME410_IVEC))
               return 0;

       bus_space_write_2(iot, ioh, BVME410_IVEC, 0x0000);
       if (bus_space_read_2(iot, ioh, BVME410_IVEC) != 0xff00)
               return 0;

       bus_space_write_2(iot, ioh, BVME410_IVEC, 0xffff);
       if (bus_space_read_2(iot, ioh, BVME410_IVEC) != 0xffff)
               return 0;

       bus_space_write_2(iot, ioh, BVME410_IVEC, 0xa5a5);
       if (bus_space_read_2(iot, ioh, BVME410_IVEC) != 0xffa5)
               return 0;

       return 1;
}

static int
bvme410_mem_size(bus_space_tag_t memt, u_long mem_addr)
{
       bus_space_handle_t memh;
       int r;

       if (bus_space_map(memt, mem_addr, 256 * 1024, 0, &memh))
               return VMECF_MEMSIZ_DEFAULT;
       if (!bus_space_peek_1(memt, memh, 0)) {
               bus_space_unmap(memt, memh, 256 * 1024);
               return VMECF_MEMSIZ_DEFAULT;
       }
       bus_space_write_1(memt, memh, 0, 128);
       bus_space_write_1(memt, memh, 64 * 1024, 32);
       bus_space_write_1(memt, memh, 32 * 1024, 8);
       r = (int)(bus_space_read_1(memt, memh, 0) * 2048);
       bus_space_unmap(memt, memh, 256 * 1024);
       return r;
}

/*
* Need to be careful when writing to the bvme410 dual port memory.
* Continue writing each byte until it reads back the same.
*/

static void
bvme410_copytobuf(struct lance_softc *sc, void *from, int boff, int len)
{
       volatile uint8_t *buf = (volatile uint8_t *)sc->sc_mem;
       uint8_t *f = (uint8_t *)from;

       for (buf += boff; len != 0; buf++, f++, len--) {
               do {
                       *buf = *f;
               } while (*buf != *f);
       }
}

static void
bvme410_zerobuf(struct lance_softc *sc, int boff, int len)
{
       volatile uint8_t *buf = (volatile uint8_t *)sc->sc_mem;

       for (buf += boff; len != 0; buf++, len--) {
               do {
                       *buf = '\0';
               } while (*buf != '\0');
       }
}