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mx98905.c revision 1.15.64.1
      1  1.15.64.1  christos /*	$NetBSD: mx98905.c,v 1.15.64.1 2019/06/10 22:07:11 christos Exp $	*/
      2        1.1     bjh21 
      3        1.1     bjh21 /*-
      4        1.1     bjh21  * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
      5        1.1     bjh21  * All rights reserved.
      6        1.1     bjh21  *
      7        1.1     bjh21  * This code is derived from software contributed to The NetBSD Foundation
      8        1.1     bjh21  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9        1.1     bjh21  * NASA Ames Research Center.
     10        1.1     bjh21  *
     11        1.1     bjh21  * Redistribution and use in source and binary forms, with or without
     12        1.1     bjh21  * modification, are permitted provided that the following conditions
     13        1.1     bjh21  * are met:
     14        1.1     bjh21  * 1. Redistributions of source code must retain the above copyright
     15        1.1     bjh21  *    notice, this list of conditions and the following disclaimer.
     16        1.1     bjh21  * 2. Redistributions in binary form must reproduce the above copyright
     17        1.1     bjh21  *    notice, this list of conditions and the following disclaimer in the
     18        1.1     bjh21  *    documentation and/or other materials provided with the distribution.
     19        1.1     bjh21  *
     20        1.1     bjh21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21        1.1     bjh21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22        1.1     bjh21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23        1.1     bjh21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24        1.1     bjh21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25        1.1     bjh21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26        1.1     bjh21  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27        1.1     bjh21  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28        1.1     bjh21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29        1.1     bjh21  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30        1.1     bjh21  * POSSIBILITY OF SUCH DAMAGE.
     31        1.1     bjh21  */
     32        1.1     bjh21 
     33        1.1     bjh21 /*
     34        1.1     bjh21  * Device driver for National Semiconductor DS8390/WD83C690 based ethernet
     35        1.1     bjh21  * adapters.
     36        1.1     bjh21  *
     37        1.1     bjh21  * Copyright (c) 1994, 1995 Charles M. Hannum.  All rights reserved.
     38        1.1     bjh21  *
     39        1.1     bjh21  * Copyright (C) 1993, David Greenman.  This software may be used, modified,
     40        1.1     bjh21  * copied, distributed, and sold, in both source and binary form provided that
     41        1.1     bjh21  * the above copyright and these terms are retained.  Under no circumstances is
     42        1.1     bjh21  * the author responsible for the proper functioning of this software, nor does
     43        1.1     bjh21  * the author assume any responsibility for damages incurred with its use.
     44        1.1     bjh21  */
     45        1.1     bjh21 
     46        1.1     bjh21 /*
     47        1.1     bjh21  * Special routines for the Macronix MX 98905.  For use with the "ne" driver.
     48        1.1     bjh21  */
     49        1.1     bjh21 
     50        1.1     bjh21 /*
     51        1.5    keihan  * <URL:http://mail-index.NetBSD.org/port-arm32/1996/06/23/0005.html>:
     52        1.1     bjh21  * There are 2 types of etherh card.  One uses the macronics chipset MX98905
     53        1.4       wiz  * and that chipset has a bug in it, in that it the MSB remote DMA
     54        1.1     bjh21  * register does not work.  There is a workaround for this which
     55        1.1     bjh21  * should be around soon.  In fact, I think only the buffer ram test
     56        1.4       wiz  * ever transfers more than 256 bytes across the DMA channel, so diabling
     57        1.1     bjh21  * it will make the mx stuff work.
     58        1.1     bjh21  */
     59        1.1     bjh21 
     60        1.1     bjh21 #include <sys/param.h>
     61        1.1     bjh21 
     62  1.15.64.1  christos __KERNEL_RCSID(0, "$NetBSD: mx98905.c,v 1.15.64.1 2019/06/10 22:07:11 christos Exp $");
     63        1.1     bjh21 
     64        1.1     bjh21 #include <sys/device.h>
     65        1.1     bjh21 #include <sys/mbuf.h>
     66        1.1     bjh21 #include <sys/socket.h>
     67        1.1     bjh21 #include <sys/syslog.h>
     68        1.1     bjh21 #include <sys/systm.h>
     69        1.1     bjh21 
     70        1.1     bjh21 #include <net/if.h>
     71        1.1     bjh21 #include <net/if_ether.h>
     72        1.1     bjh21 #include <net/if_media.h>
     73        1.1     bjh21 
     74       1.10        ad #include <sys/bus.h>
     75        1.1     bjh21 
     76        1.1     bjh21 #include <dev/ic/dp8390reg.h>
     77        1.1     bjh21 #include <dev/ic/dp8390var.h>
     78        1.1     bjh21 #include <dev/ic/ne2000reg.h>
     79        1.1     bjh21 #include <dev/ic/ne2000var.h>
     80        1.1     bjh21 #include <dev/ic/mx98905var.h>
     81        1.1     bjh21 
     82        1.1     bjh21 #ifndef __BUS_SPACE_HAS_STREAM_METHODS
     83        1.1     bjh21 #define	bus_space_write_stream_2	bus_space_write_2
     84        1.1     bjh21 #define	bus_space_write_multi_stream_2	bus_space_write_multi_2
     85        1.1     bjh21 #define	bus_space_read_multi_stream_2	bus_space_read_multi_2
     86        1.1     bjh21 #endif /* __BUS_SPACE_HAS_STREAM_METHODS */
     87        1.2     bjh21 
     88        1.8     perry static inline void mx98905_write_setup(struct dp8390_softc *, int, int);
     89        1.8     perry static inline void mx98905_write_wait(struct dp8390_softc *);
     90        1.1     bjh21 
     91        1.1     bjh21 void
     92        1.1     bjh21 mx98905_attach(struct dp8390_softc *sc)
     93        1.1     bjh21 {
     94        1.1     bjh21 
     95        1.1     bjh21 	sc->ring_copy = mx98905_ring_copy;
     96        1.1     bjh21 	sc->write_mbuf = mx98905_write_mbuf;
     97        1.1     bjh21 	sc->read_hdr = mx98905_read_hdr;
     98        1.1     bjh21 }
     99        1.1     bjh21 
    100        1.8     perry static inline void
    101       1.15       dsl mx98905_write_setup(struct dp8390_softc *sc, int len, int buf)
    102        1.1     bjh21 {
    103        1.1     bjh21 	bus_space_tag_t nict = sc->sc_regt;
    104        1.1     bjh21 	bus_space_handle_t nich = sc->sc_regh;
    105        1.1     bjh21 
    106        1.1     bjh21 	/* Select page 0 registers. */
    107        1.1     bjh21 	NIC_BARRIER(nict, nich);
    108        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_CR,
    109        1.1     bjh21 	    ED_CR_RD2 | ED_CR_PAGE_0 | ED_CR_STA);
    110        1.1     bjh21 	NIC_BARRIER(nict, nich);
    111        1.1     bjh21 
    112        1.1     bjh21 	/* Reset remote DMA complete flag. */
    113        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_ISR, ED_ISR_RDC);
    114        1.1     bjh21 	NIC_BARRIER(nict, nich);
    115        1.1     bjh21 
    116        1.1     bjh21 	/* Set up DMA byte count. */
    117        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RBCR0, len);
    118        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RBCR1, len >> 8);
    119        1.1     bjh21 
    120        1.1     bjh21 	/* Set up destination address in NIC mem. */
    121        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RSAR0, buf);
    122        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RSAR1, buf >> 8);
    123        1.1     bjh21 
    124        1.1     bjh21 	/* Set remote DMA write. */
    125        1.1     bjh21 	NIC_BARRIER(nict, nich);
    126        1.1     bjh21 	bus_space_write_1(nict, nich,
    127        1.1     bjh21 	    ED_P0_CR, ED_CR_RD1 | ED_CR_PAGE_0 | ED_CR_STA);
    128        1.1     bjh21 	NIC_BARRIER(nict, nich);
    129        1.1     bjh21 }
    130        1.1     bjh21 
    131        1.1     bjh21 
    132        1.8     perry static inline void
    133       1.14       dsl mx98905_write_wait(struct dp8390_softc *sc)
    134        1.1     bjh21 {
    135        1.1     bjh21 	int maxwait = 100;	/* about 120us */
    136        1.1     bjh21 	bus_space_tag_t nict = sc->sc_regt;
    137        1.1     bjh21 	bus_space_handle_t nich = sc->sc_regh;
    138        1.1     bjh21 
    139        1.1     bjh21 	/*
    140        1.1     bjh21 	 * Wait for remote DMA to complete.  This is necessary because on the
    141        1.1     bjh21 	 * transmit side, data is handled internally by the NIC in bursts, and
    142        1.1     bjh21 	 * we can't start another remote DMA until this one completes.  Not
    143        1.1     bjh21 	 * waiting causes really bad things to happen - like the NIC wedging
    144        1.1     bjh21 	 * the bus.
    145        1.1     bjh21 	 */
    146        1.1     bjh21 	while (((bus_space_read_1(nict, nich, ED_P0_ISR) & ED_ISR_RDC) !=
    147        1.1     bjh21 	    ED_ISR_RDC) && --maxwait) {
    148        1.1     bjh21 		bus_space_read_1(nict, nich, ED_P0_CRDA1);
    149        1.1     bjh21 		bus_space_read_1(nict, nich, ED_P0_CRDA0);
    150        1.1     bjh21 		NIC_BARRIER(nict, nich);
    151        1.1     bjh21 		DELAY(1);
    152        1.1     bjh21 	}
    153        1.1     bjh21 
    154        1.1     bjh21 	if (maxwait == 0) {
    155        1.1     bjh21 		log(LOG_WARNING,
    156        1.1     bjh21 		    "%s: remote transmit DMA failed to complete\n",
    157       1.12      cube 		    device_xname(sc->sc_dev));
    158        1.1     bjh21 		dp8390_reset(sc);
    159        1.1     bjh21 	}
    160        1.1     bjh21 }
    161        1.1     bjh21 
    162        1.1     bjh21 /*
    163        1.1     bjh21  * Write an mbuf chain to the destination NIC memory address using programmed
    164        1.1     bjh21  * I/O.
    165        1.1     bjh21  */
    166        1.1     bjh21 int
    167       1.14       dsl mx98905_write_mbuf(struct dp8390_softc *sc, struct mbuf *m, int buf)
    168        1.1     bjh21 {
    169        1.1     bjh21 	struct ne2000_softc *nsc = (struct ne2000_softc *)sc;
    170        1.1     bjh21 	bus_space_tag_t nict = sc->sc_regt;
    171        1.1     bjh21 	bus_space_handle_t nich = sc->sc_regh;
    172        1.1     bjh21 	bus_space_tag_t asict = nsc->sc_asict;
    173        1.1     bjh21 	bus_space_handle_t asich = nsc->sc_asich;
    174        1.1     bjh21 	int savelen, dmalen, resid, len;
    175        1.1     bjh21 	u_int8_t *data, savebyte[2];
    176        1.1     bjh21 	int l, leftover;
    177        1.1     bjh21 #ifdef DIAGNOSTIC
    178        1.1     bjh21 	u_int8_t *lim;
    179        1.1     bjh21 #endif
    180        1.3    bouyer 	int i;
    181        1.1     bjh21 
    182        1.1     bjh21 	resid = savelen = m->m_pkthdr.len;
    183        1.1     bjh21 
    184  1.15.64.1  christos 	dmalen = uimin(resid, 254);
    185        1.1     bjh21 
    186        1.1     bjh21 	mx98905_write_setup(sc, dmalen, buf);
    187        1.1     bjh21 
    188        1.1     bjh21 	buf += dmalen;
    189        1.1     bjh21 	resid -= dmalen;
    190        1.1     bjh21 
    191        1.1     bjh21 	/*
    192        1.1     bjh21 	 * Transfer the mbuf chain to the NIC memory.  NE2000 cards
    193        1.1     bjh21 	 * require that data be transferred as words, and only words,
    194        1.1     bjh21 	 * so that case requires some extra code to patch over odd-length
    195        1.1     bjh21 	 * mbufs.
    196        1.1     bjh21 	 */
    197        1.1     bjh21 	/* NE2000s are a bit trickier. */
    198        1.1     bjh21 	/* Start out with no leftover data. */
    199        1.1     bjh21 	leftover = 0;
    200        1.1     bjh21 	savebyte[0] = savebyte[1] = 0;
    201        1.1     bjh21 
    202        1.1     bjh21 	for (; m != 0; m = m->m_next) {
    203        1.1     bjh21 		l = m->m_len;
    204        1.1     bjh21 		if (l == 0)
    205        1.1     bjh21 			continue;
    206        1.1     bjh21 		data = mtod(m, u_int8_t *);
    207        1.1     bjh21 #ifdef DIAGNOSTIC
    208        1.1     bjh21 		lim = data + l;
    209        1.1     bjh21 #endif
    210        1.1     bjh21 		while (l > 0) {
    211        1.1     bjh21 			if (leftover) {
    212        1.1     bjh21 				/*
    213        1.1     bjh21 				 * Data left over (from mbuf or
    214        1.1     bjh21 				 * realignment).  Buffer the next
    215        1.1     bjh21 				 * byte, and write it and the leftover
    216        1.1     bjh21 				 * data out.
    217        1.1     bjh21 				 */
    218        1.1     bjh21 				savebyte[1] = *data++;
    219        1.1     bjh21 				l--;
    220        1.1     bjh21 				bus_space_write_stream_2(asict, asich,
    221        1.1     bjh21 				    NE2000_ASIC_DATA, *(u_int16_t *)savebyte);
    222        1.1     bjh21 				dmalen -= 2;
    223        1.1     bjh21 				leftover = 0;
    224        1.1     bjh21 			} else if (BUS_SPACE_ALIGNED_POINTER(data,
    225        1.1     bjh21 			    u_int16_t) == 0) {
    226        1.1     bjh21 				/* Unaligned data; buffer the next byte. */
    227        1.1     bjh21 				savebyte[0] = *data++;
    228        1.1     bjh21 				l--;
    229        1.1     bjh21 				leftover = 1;
    230        1.1     bjh21 			} else {
    231        1.1     bjh21 				/*
    232        1.1     bjh21 				 * Aligned data; output contiguous
    233        1.1     bjh21 				 * words as much as we can, then
    234        1.1     bjh21 				 * buffer the remaining byte, if any.
    235        1.1     bjh21 				 */
    236  1.15.64.1  christos 				len = uimin(l, dmalen);
    237        1.1     bjh21 				leftover = len & 1;
    238        1.1     bjh21 				len &= ~1;
    239        1.1     bjh21 				bus_space_write_multi_stream_2(asict,
    240        1.1     bjh21 				    asich, NE2000_ASIC_DATA,
    241        1.1     bjh21 				    (u_int16_t *)data, len >> 1);
    242        1.1     bjh21 				dmalen -= len;
    243        1.1     bjh21 				data += len;
    244        1.1     bjh21 				if (leftover)
    245        1.1     bjh21 					savebyte[0] = *data++;
    246        1.1     bjh21 				l -= len + leftover;
    247        1.1     bjh21 			}
    248        1.1     bjh21 			if (dmalen == 0 && resid > 0) {
    249        1.1     bjh21 				mx98905_write_wait(sc);
    250  1.15.64.1  christos 				dmalen = uimin(resid, 254);
    251        1.1     bjh21 
    252        1.1     bjh21 				mx98905_write_setup(sc, dmalen, buf);
    253        1.1     bjh21 
    254        1.1     bjh21 				buf += dmalen;
    255        1.1     bjh21 				resid -= dmalen;
    256        1.1     bjh21 			}
    257        1.1     bjh21 		}
    258        1.1     bjh21 		if (l < 0)
    259        1.1     bjh21 			panic("mx98905_write_mbuf: negative len");
    260        1.1     bjh21 #ifdef DIAGNOSTIC
    261        1.1     bjh21 		if (data != lim)
    262        1.1     bjh21 			panic("mx98905_write_mbuf: data != lim");
    263        1.1     bjh21 #endif
    264        1.1     bjh21 	}
    265        1.1     bjh21 	if (leftover) {
    266        1.1     bjh21 		savebyte[1] = 0;
    267        1.1     bjh21 		bus_space_write_stream_2(asict, asich, NE2000_ASIC_DATA,
    268        1.1     bjh21 		    *(u_int16_t *)savebyte);
    269        1.3    bouyer 	}
    270        1.3    bouyer 	if (savelen < ETHER_MIN_LEN - ETHER_CRC_LEN) {
    271        1.3    bouyer 		for(i = 0; i < (ETHER_MIN_LEN - ETHER_CRC_LEN - savelen) >> 1;
    272        1.3    bouyer 		    i++)
    273        1.3    bouyer 			bus_space_write_stream_2(asict, asich,
    274        1.3    bouyer 			    NE2000_ASIC_DATA, 0);
    275        1.3    bouyer 		savelen = ETHER_MIN_LEN - ETHER_CRC_LEN;
    276        1.1     bjh21 	}
    277        1.1     bjh21 	NIC_BARRIER(nict, nich);
    278        1.1     bjh21 
    279        1.1     bjh21 	mx98905_write_wait(sc);
    280        1.1     bjh21 
    281        1.1     bjh21 	return (savelen);
    282        1.1     bjh21 }
    283        1.1     bjh21 
    284        1.1     bjh21 /*
    285        1.1     bjh21  * Given a source and destination address, copy 'amout' of a packet from
    286        1.1     bjh21  * the ring buffer into a linear destination buffer.  Takes into account
    287        1.1     bjh21  * ring-wrap.
    288        1.1     bjh21  */
    289        1.1     bjh21 int
    290       1.14       dsl mx98905_ring_copy(struct dp8390_softc *sc, int src, void *vdst, u_short amount)
    291        1.1     bjh21 {
    292        1.1     bjh21 	struct ne2000_softc *nsc = (struct ne2000_softc *)sc;
    293       1.11      matt 	uint8_t *dst = vdst;
    294        1.1     bjh21 	bus_space_tag_t nict = sc->sc_regt;
    295        1.1     bjh21 	bus_space_handle_t nich = sc->sc_regh;
    296        1.1     bjh21 	bus_space_tag_t asict = nsc->sc_asict;
    297        1.1     bjh21 	bus_space_handle_t asich = nsc->sc_asich;
    298        1.1     bjh21 	u_short tmp_amount;
    299        1.6        he 	int useword = nsc->sc_useword;
    300        1.1     bjh21 
    301        1.1     bjh21 	/* Does copy wrap to lower addr in ring buffer? */
    302        1.1     bjh21 	if (src + amount > sc->mem_end) {
    303        1.1     bjh21 		tmp_amount = sc->mem_end - src;
    304        1.1     bjh21 
    305        1.1     bjh21 		/* Copy amount up to end of NIC memory. */
    306        1.1     bjh21 		mx98905_readmem(nict, nich, asict, asich, src,
    307        1.1     bjh21 		    (u_int8_t *)dst, tmp_amount, useword);
    308        1.1     bjh21 
    309        1.1     bjh21 		amount -= tmp_amount;
    310        1.1     bjh21 		src = sc->mem_ring;
    311        1.1     bjh21 		dst += tmp_amount;
    312        1.1     bjh21 	}
    313        1.1     bjh21 
    314       1.11      matt 	mx98905_readmem(nict, nich, asict, asich, src, dst, amount, useword);
    315        1.1     bjh21 
    316        1.1     bjh21 	return (src + amount);
    317        1.1     bjh21 }
    318        1.1     bjh21 
    319        1.1     bjh21 void
    320       1.14       dsl mx98905_read_hdr(struct dp8390_softc *sc, int buf, struct dp8390_ring *hdr)
    321        1.1     bjh21 {
    322        1.1     bjh21 	struct ne2000_softc *nsc = (struct ne2000_softc *)sc;
    323        1.1     bjh21 
    324        1.1     bjh21 	mx98905_readmem(sc->sc_regt, sc->sc_regh, nsc->sc_asict, nsc->sc_asich,
    325        1.1     bjh21 	    buf, (u_int8_t *)hdr, sizeof(struct dp8390_ring),
    326        1.6        he 	    nsc->sc_useword);
    327        1.1     bjh21 #if BYTE_ORDER == BIG_ENDIAN
    328        1.1     bjh21 	hdr->count = bswap16(hdr->count);
    329        1.1     bjh21 #endif
    330        1.1     bjh21 }
    331        1.1     bjh21 
    332        1.8     perry static inline void
    333        1.1     bjh21 mx98905_read_setup(bus_space_tag_t nict, bus_space_handle_t nich,
    334        1.1     bjh21     int len, int buf)
    335        1.1     bjh21 {
    336        1.1     bjh21 
    337        1.1     bjh21 	/* Select page 0 registers. */
    338        1.1     bjh21 	NIC_BARRIER(nict, nich);
    339        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_CR,
    340        1.1     bjh21 	    ED_CR_RD2 | ED_CR_PAGE_0 | ED_CR_STA);
    341        1.1     bjh21 	NIC_BARRIER(nict, nich);
    342        1.1     bjh21 
    343        1.1     bjh21 	/* Set up DMA byte count. */
    344        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RBCR0, len);
    345        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RBCR1, len >> 8);
    346        1.1     bjh21 
    347        1.1     bjh21 	/* Set up source address in NIC mem. */
    348        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RSAR0, buf);
    349        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_RSAR1, buf >> 8);
    350        1.1     bjh21 
    351        1.1     bjh21 	NIC_BARRIER(nict, nich);
    352        1.1     bjh21 	bus_space_write_1(nict, nich, ED_P0_CR,
    353        1.1     bjh21 	    ED_CR_RD0 | ED_CR_PAGE_0 | ED_CR_STA);
    354        1.1     bjh21 
    355        1.1     bjh21 	bus_space_barrier(nict, nich, 0, NE2000_NPORTS,
    356        1.1     bjh21 			  BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
    357        1.1     bjh21 }
    358        1.1     bjh21 
    359        1.1     bjh21 /*
    360        1.1     bjh21  * Given a NIC memory source address and a host memory destination address,
    361        1.1     bjh21  * copy 'amount' from NIC to host using programmed i/o.  The 'amount' is
    362        1.1     bjh21  * rounded up to a word - ok as long as mbufs are word sized.
    363        1.1     bjh21  */
    364        1.1     bjh21 void
    365       1.14       dsl mx98905_readmem(bus_space_tag_t nict, bus_space_handle_t nich, bus_space_tag_t asict, bus_space_handle_t asich, int src, u_int8_t *dst, size_t amount, int useword)
    366        1.1     bjh21 {
    367        1.1     bjh21 	int len, resid;
    368        1.1     bjh21 
    369        1.1     bjh21 	resid = amount;
    370        1.1     bjh21 	/* Round up to a word. */
    371        1.1     bjh21 	if (resid & 1)
    372        1.1     bjh21 		++resid;
    373        1.1     bjh21 
    374        1.1     bjh21 	while (resid > 0) {
    375  1.15.64.1  christos 		len = uimin(resid, 254);
    376        1.1     bjh21 		mx98905_read_setup(nict, nich, len, src);
    377        1.1     bjh21 		if (useword)
    378        1.1     bjh21 			bus_space_read_multi_stream_2(asict, asich,
    379        1.1     bjh21 			    NE2000_ASIC_DATA, (u_int16_t *)dst, len >> 1);
    380        1.1     bjh21 		else
    381        1.1     bjh21 			bus_space_read_multi_1(asict, asich, NE2000_ASIC_DATA,
    382        1.1     bjh21 			    dst, len);
    383        1.1     bjh21 		resid -= len;
    384        1.1     bjh21 		src += len;
    385        1.1     bjh21 		dst += len;
    386        1.1     bjh21 	}
    387        1.1     bjh21 }
    388