xref: /netbsd-src/sys/dev/pci/if_sip.c (revision 3b435a73967be44dfb4a27315acd72bfacde430c)
1 /*	$NetBSD: if_sip.c,v 1.2 1999/08/03 17:25:52 thorpej Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999 Network Computer, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of Network Computer, Inc. nor the names of its
16  *    contributors may be used to endorse or promote products derived
17  *    from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY NETWORK COMPUTER, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Device driver for the Silicon Integrated Systems SiS900 10/100 PCI
34  * Ethernet controller.
35  *
36  * Written by Jason R. Thorpe for Network Computer, Inc.
37  */
38 
39 #include "opt_inet.h"
40 #include "opt_ns.h"
41 #include "bpfilter.h"
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/mbuf.h>
46 #include <sys/malloc.h>
47 #include <sys/kernel.h>
48 #include <sys/socket.h>
49 #include <sys/ioctl.h>
50 #include <sys/errno.h>
51 #include <sys/device.h>
52 #include <sys/queue.h>
53 
54 #include <vm/vm.h>		/* for PAGE_SIZE */
55 
56 #include <net/if.h>
57 #include <net/if_dl.h>
58 #include <net/if_media.h>
59 #include <net/if_ether.h>
60 
61 #if NBPFILTER > 0
62 #include <net/bpf.h>
63 #endif
64 
65 #ifdef INET
66 #include <netinet/in.h>
67 #include <netinet/if_inarp.h>
68 #endif
69 
70 #ifdef NS
71 #include <netns/ns.h>
72 #include <netns/ns_if.h>
73 #endif
74 
75 #include <machine/bus.h>
76 #include <machine/intr.h>
77 
78 #include <dev/mii/miivar.h>
79 
80 #include <dev/pci/pcireg.h>
81 #include <dev/pci/pcivar.h>
82 #include <dev/pci/pcidevs.h>
83 
84 #include <dev/pci/if_sipreg.h>
85 
86 /*
87  * Devices supported by this driver.
88  */
89 const struct sip_product {
90 	pci_vendor_id_t		sip_vendor;
91 	pci_product_id_t	sip_product;
92 	const char		*sip_name;
93 } sip_products[] = {
94 	{ PCI_VENDOR_SIS,	PCI_PRODUCT_SIS_900,
95 	  "SiS 900 10/100 Ethernet" },
96 
97 	{ 0,			0,
98 	  NULL },
99 };
100 
101 /*
102  * Transmit descriptor list size.  This is arbitrary, but allocate
103  * enough descriptors for 64 pending transmissions, and 16 segments
104  * per packet.  This MUST work out to a power of 2.
105  */
106 #define	SIP_NTXSEGS		16
107 
108 #define	SIP_TXQUEUELEN		64
109 #define	SIP_NTXDESC		(SIP_TXQUEUELEN * SIP_NTXSEGS)
110 #define	SIP_NTXDESC_MASK	(SIP_NTXDESC - 1)
111 #define	SIP_NEXTTX(x)		(((x) + 1) & SIP_NTXDESC_MASK)
112 
113 /*
114  * Receive descriptor list size.  We have one Rx buffer per incoming
115  * packet, so this logic is a little simpler.
116  */
117 #define	SIP_NRXDESC		64
118 #define	SIP_NRXDESC_MASK	(SIP_NRXDESC - 1)
119 #define	SIP_NEXTRX(x)		(((x) + 1) & SIP_NRXDESC_MASK)
120 
121 /*
122  * Control structures are DMA'd to the SiS900 chip.  We allocate them in
123  * a single clump that maps to a single DMA segment to make several things
124  * easier.
125  */
126 struct sip_control_data {
127 	/*
128 	 * The transmit descriptors.
129 	 */
130 	struct sip_desc scd_txdescs[SIP_NTXDESC];
131 
132 	/*
133 	 * The receive descriptors.
134 	 */
135 	struct sip_desc scd_rxdescs[SIP_NRXDESC];
136 };
137 
138 #define	SIP_CDOFF(x)	offsetof(struct sip_control_data, x)
139 #define	SIP_CDTXOFF(x)	SIP_CDOFF(scd_txdescs[(x)])
140 #define	SIP_CDRXOFF(x)	SIP_CDOFF(scd_rxdescs[(x)])
141 
142 /*
143  * Software state for transmit jobs.
144  */
145 struct sip_txsoft {
146 	struct mbuf *txs_mbuf;		/* head of our mbuf chain */
147 	bus_dmamap_t txs_dmamap;	/* our DMA map */
148 	int txs_firstdesc;		/* first descriptor in packet */
149 	int txs_lastdesc;		/* last descriptor in packet */
150 	SIMPLEQ_ENTRY(sip_txsoft) txs_q;
151 };
152 
153 SIMPLEQ_HEAD(sip_txsq, sip_txsoft);
154 
155 /*
156  * Software state for receive jobs.
157  */
158 struct sip_rxsoft {
159 	struct mbuf *rxs_mbuf;		/* head of our mbuf chain */
160 	bus_dmamap_t rxs_dmamap;	/* our DMA map */
161 };
162 
163 /*
164  * Software state per device.
165  */
166 struct sip_softc {
167 	struct device sc_dev;		/* generic device information */
168 	bus_space_tag_t sc_st;		/* bus space tag */
169 	bus_space_handle_t sc_sh;	/* bus space handle */
170 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
171 	struct ethercom sc_ethercom;	/* ethernet common data */
172 	void *sc_sdhook;		/* shutdown hook */
173 
174 	void *sc_ih;			/* interrupt cookie */
175 
176 	struct mii_data sc_mii;		/* MII/media information */
177 
178 	bus_dmamap_t sc_cddmamap;	/* control data DMA map */
179 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
180 
181 	/*
182 	 * Software state for transmit and receive descriptors.
183 	 */
184 	struct sip_txsoft sc_txsoft[SIP_TXQUEUELEN];
185 	struct sip_rxsoft sc_rxsoft[SIP_NRXDESC];
186 
187 	/*
188 	 * Control data structures.
189 	 */
190 	struct sip_control_data *sc_control_data;
191 #define	sc_txdescs	sc_control_data->scd_txdescs
192 #define	sc_rxdescs	sc_control_data->scd_rxdescs
193 
194 	u_int32_t sc_txcfg;		/* prototype TXCFG register */
195 	u_int32_t sc_rxcfg;		/* prototype RXCFG register */
196 	u_int32_t sc_imr;		/* prototype IMR register */
197 	u_int32_t sc_rfcr;		/* prototype RFCR register */
198 
199 	u_int32_t sc_tx_fill_thresh;	/* transmit fill threshold */
200 	u_int32_t sc_tx_drain_thresh;	/* transmit drain threshold */
201 
202 	u_int32_t sc_rx_drain_thresh;	/* receive drain threshold */
203 
204 	int	sc_flags;		/* misc. flags; see below */
205 
206 	int	sc_txfree;		/* number of free Tx descriptors */
207 	int	sc_txnext;		/* next ready Tx descriptor */
208 
209 	struct sip_txsq sc_txfreeq;	/* free Tx descsofts */
210 	struct sip_txsq sc_txdirtyq;	/* dirty Tx descsofts */
211 
212 	int	sc_rxptr;		/* next ready Rx descriptor/descsoft */
213 };
214 
215 /* sc_flags */
216 #define	SIPF_PAUSED	0x00000001	/* paused (802.3x flow control) */
217 
218 #define	SIP_CDTXADDR(sc, x)	((sc)->sc_cddma + SIP_CDTXOFF((x)))
219 #define	SIP_CDRXADDR(sc, x)	((sc)->sc_cddma + SIP_CDRXOFF((x)))
220 
221 #define	SIP_CDTXSYNC(sc, x, n, ops)					\
222 do {									\
223 	int __x, __n;							\
224 									\
225 	__x = (x);							\
226 	__n = (n);							\
227 									\
228 	/* If it will wrap around, sync to the end of the ring. */	\
229 	if ((__x + __n) > SIP_NTXDESC) {				\
230 		bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,	\
231 		    SIP_CDTXOFF(__x), sizeof(struct sip_desc) *		\
232 		    (SIP_NTXDESC - __x), (ops));			\
233 		__n -= (SIP_NTXDESC - __x);				\
234 		__x = 0;						\
235 	}								\
236 									\
237 	/* Now sync whatever is left. */				\
238 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
239 	    SIP_CDTXOFF(__x), sizeof(struct sip_desc) * __n, (ops));	\
240 } while (0)
241 
242 #define	SIP_CDRXSYNC(sc, x, ops)					\
243 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
244 	    SIP_CDRXOFF((x)), sizeof(struct sip_desc), (ops))
245 
246 /*
247  * Note we rely on MCLBYTES being a power of two below.
248  */
249 #define	SIP_INIT_RXDESC(sc, x)						\
250 do {									\
251 	struct sip_rxsoft *__rxs = &(sc)->sc_rxsoft[(x)];		\
252 	struct sip_desc *__sipd = &(sc)->sc_rxdescs[(x)];		\
253 									\
254 	__sipd->sipd_link = SIP_CDRXADDR((sc), SIP_NEXTRX((x)));	\
255 	__sipd->sipd_bufptr = __rxs->rxs_dmamap->dm_segs[0].ds_addr;	\
256 	__sipd->sipd_cmdsts = CMDSTS_INTR |				\
257 	    ((MCLBYTES - 1) & CMDSTS_SIZE_MASK);			\
258 	SIP_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE); \
259 } while (0)
260 
261 void	sip_start __P((struct ifnet *));
262 void	sip_watchdog __P((struct ifnet *));
263 int	sip_ioctl __P((struct ifnet *, u_long, caddr_t));
264 
265 void	sip_shutdown __P((void *));
266 
267 void	sip_reset __P((struct sip_softc *));
268 int	sip_init __P((struct sip_softc *));
269 void	sip_stop __P((struct sip_softc *, int));
270 void	sip_rxdrain __P((struct sip_softc *));
271 int	sip_add_rxbuf __P((struct sip_softc *, int));
272 void	sip_read_eeprom __P((struct sip_softc *, int, int, u_int16_t *));
273 void	sip_set_filter __P((struct sip_softc *));
274 void	sip_tick __P((void *));
275 
276 int	sip_intr __P((void *));
277 void	sip_txintr __P((struct sip_softc *));
278 void	sip_rxintr __P((struct sip_softc *));
279 
280 int	sip_mii_readreg __P((struct device *, int, int));
281 void	sip_mii_writereg __P((struct device *, int, int, int));
282 void	sip_mii_statchg __P((struct device *));
283 
284 int	sip_mediachange __P((struct ifnet *));
285 void	sip_mediastatus __P((struct ifnet *, struct ifmediareq *));
286 
287 int	sip_match __P((struct device *, struct cfdata *, void *));
288 void	sip_attach __P((struct device *, struct device *, void *));
289 
290 int	sip_copy_small = 0;
291 
292 struct cfattach sip_ca = {
293 	sizeof(struct sip_softc), sip_match, sip_attach,
294 };
295 
296 const struct sip_product *sip_lookup __P((const struct pci_attach_args *));
297 
298 const struct sip_product *
299 sip_lookup(pa)
300 	const struct pci_attach_args *pa;
301 {
302 	const struct sip_product *sip;
303 
304 	for (sip = sip_products; sip->sip_name != NULL; sip++) {
305 		if (PCI_VENDOR(pa->pa_id) == sip->sip_vendor &&
306 		    PCI_PRODUCT(pa->pa_id) == sip->sip_product)
307 			return (sip);
308 	}
309 	return (NULL);
310 }
311 
312 int
313 sip_match(parent, cf, aux)
314 	struct device *parent;
315 	struct cfdata *cf;
316 	void *aux;
317 {
318 	struct pci_attach_args *pa = aux;
319 
320 	if (sip_lookup(pa) != NULL)
321 		return (1);
322 
323 	return (0);
324 }
325 
326 void
327 sip_attach(parent, self, aux)
328 	struct device *parent, *self;
329 	void *aux;
330 {
331 	struct sip_softc *sc = (struct sip_softc *) self;
332 	struct pci_attach_args *pa = aux;
333 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
334 	pci_chipset_tag_t pc = pa->pa_pc;
335 	pci_intr_handle_t ih;
336 	const char *intrstr = NULL;
337 	bus_space_tag_t iot, memt;
338 	bus_space_handle_t ioh, memh;
339 	bus_dma_segment_t seg;
340 	int ioh_valid, memh_valid;
341 	int i, rseg, error;
342 	const struct sip_product *sip;
343 	pcireg_t pmode;
344 	u_int16_t enaddr[ETHER_ADDR_LEN / 2];
345 
346 	sip = sip_lookup(pa);
347 	if (sip == NULL) {
348 		printf("\n");
349 		panic("sip_attach: impossible");
350 	}
351 
352 	printf(": %s\n", sip->sip_name);
353 
354 	/*
355 	 * Map the device.
356 	 */
357 	ioh_valid = (pci_mapreg_map(pa, SIP_PCI_CFGIOA,
358 	    PCI_MAPREG_TYPE_IO, 0,
359 	    &iot, &ioh, NULL, NULL) == 0);
360 	memh_valid = (pci_mapreg_map(pa, SIP_PCI_CFGMA,
361 	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
362 	    &memt, &memh, NULL, NULL) == 0);
363 
364 	if (memh_valid) {
365 		sc->sc_st = memt;
366 		sc->sc_sh = memh;
367 	} else if (ioh_valid) {
368 		sc->sc_st = iot;
369 		sc->sc_sh = ioh;
370 	} else {
371 		printf("%s: unable to map device registers\n",
372 		    sc->sc_dev.dv_xname);
373 		return;
374 	}
375 
376 	sc->sc_dmat = pa->pa_dmat;
377 
378 	/* Enable bus mastering. */
379 	pci_conf_write(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
380 	    pci_conf_read(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG) |
381 	    PCI_COMMAND_MASTER_ENABLE);
382 
383 	/* Get it out of power save mode if needed. */
384 	if (pci_get_capability(pc, pa->pa_tag, PCI_CAP_PWRMGMT, 0, 0)) {
385 		pmode = pci_conf_read(pc, pa->pa_tag, SIP_PCI_CFGPMCSR) & 0x3;
386 		if (pmode == 3) {
387 			/*
388 			 * The card has lost all configuration data in
389 			 * this state, so punt.
390 			 */
391 			printf("%s: unable to wake up from power state D3\n",
392 			    sc->sc_dev.dv_xname);
393 			return;
394 		}
395 		if (pmode != 0) {
396 			printf("%s: waking up from power state D%d\n",
397 			    sc->sc_dev.dv_xname, pmode);
398 			pci_conf_write(pc, pa->pa_tag, SIP_PCI_CFGPMCSR, 0);
399 		}
400 	}
401 
402 	/*
403 	 * Map and establish our interrupt.
404 	 */
405 	if (pci_intr_map(pc, pa->pa_intrtag, pa->pa_intrpin,
406 	    pa->pa_intrline, &ih)) {
407 		printf("%s: unable to map interrupt\n", sc->sc_dev.dv_xname);
408 		return;
409 	}
410 	intrstr = pci_intr_string(pc, ih);
411 	sc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, sip_intr, sc);
412 	if (sc->sc_ih == NULL) {
413 		printf("%s: unable to establish interrupt",
414 		    sc->sc_dev.dv_xname);
415 		if (intrstr != NULL)
416 			printf(" at %s", intrstr);
417 		printf("\n");
418 		return;
419 	}
420 	printf("%s: interrupting at %s\n", sc->sc_dev.dv_xname, intrstr);
421 
422 	SIMPLEQ_INIT(&sc->sc_txfreeq);
423 	SIMPLEQ_INIT(&sc->sc_txdirtyq);
424 
425 	/*
426 	 * Allocate the control data structures, and create and load the
427 	 * DMA map for it.
428 	 */
429 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
430 	    sizeof(struct sip_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
431 	    0)) != 0) {
432 		printf("%s: unable to allocate control data, error = %d\n",
433 		    sc->sc_dev.dv_xname, error);
434 		goto fail_0;
435 	}
436 
437 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
438 	    sizeof(struct sip_control_data), (caddr_t *)&sc->sc_control_data,
439 	    BUS_DMA_COHERENT)) != 0) {
440 		printf("%s: unable to map control data, error = %d\n",
441 		    sc->sc_dev.dv_xname, error);
442 		goto fail_1;
443 	}
444 
445 	if ((error = bus_dmamap_create(sc->sc_dmat,
446 	    sizeof(struct sip_control_data), 1,
447 	    sizeof(struct sip_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
448 		printf("%s: unable to create control data DMA map, "
449 		    "error = %d\n", sc->sc_dev.dv_xname, error);
450 		goto fail_2;
451 	}
452 
453 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
454 	    sc->sc_control_data, sizeof(struct sip_control_data), NULL,
455 	    0)) != 0) {
456 		printf("%s: unable to load control data DMA map, error = %d\n",
457 		    sc->sc_dev.dv_xname, error);
458 		goto fail_3;
459 	}
460 
461 	/*
462 	 * Create the transmit buffer DMA maps.
463 	 */
464 	for (i = 0; i < SIP_TXQUEUELEN; i++) {
465 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
466 		    SIP_NTXSEGS, MCLBYTES, 0, 0,
467 		    &sc->sc_txsoft[i].txs_dmamap)) != 0) {
468 			printf("%s: unable to create tx DMA map %d, "
469 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
470 			goto fail_4;
471 		}
472 	}
473 
474 	/*
475 	 * Create the receive buffer DMA maps.
476 	 */
477 	for (i = 0; i < SIP_NRXDESC; i++) {
478 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
479 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
480 			printf("%s: unable to create rx DMA map %d, "
481 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
482 			goto fail_5;
483 		}
484 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
485 	}
486 
487 	/*
488 	 * Reset the chip to a known state.
489 	 */
490 	sip_reset(sc);
491 
492 	/*
493 	 * Read the Ethernet address from the EEPROM.
494 	 */
495 	sip_read_eeprom(sc, SIP_EEPROM_ETHERNET_ID0 >> 1,
496 	    sizeof(enaddr) / sizeof(enaddr[0]), enaddr);
497 
498 	printf("%s: Ethernet address %s\n", sc->sc_dev.dv_xname,
499 	    ether_sprintf((u_int8_t *)enaddr));
500 
501 	/*
502 	 * Initialize our media structures and probe the MII.
503 	 */
504 	sc->sc_mii.mii_ifp = ifp;
505 	sc->sc_mii.mii_readreg = sip_mii_readreg;
506 	sc->sc_mii.mii_writereg = sip_mii_writereg;
507 	sc->sc_mii.mii_statchg = sip_mii_statchg;
508 	ifmedia_init(&sc->sc_mii.mii_media, 0, sip_mediachange,
509 	    sip_mediastatus);
510 	mii_phy_probe(&sc->sc_dev, &sc->sc_mii, 0xffffffff);
511 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
512 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
513 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
514 	} else
515 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
516 
517 	ifp = &sc->sc_ethercom.ec_if;
518 	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
519 	ifp->if_softc = sc;
520 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
521 	ifp->if_ioctl = sip_ioctl;
522 	ifp->if_start = sip_start;
523 	ifp->if_watchdog = sip_watchdog;
524 
525 	/*
526 	 * Attach the interface.
527 	 */
528 	if_attach(ifp);
529 	ether_ifattach(ifp, (u_int8_t *)enaddr);
530 #if NBPFILTER > 0
531 	bpfattach(&sc->sc_ethercom.ec_if.if_bpf, ifp, DLT_EN10MB,
532 	    sizeof(struct ether_header));
533 #endif
534 
535 	/*
536 	 * Make sure the interface is shutdown during reboot.
537 	 */
538 	sc->sc_sdhook = shutdownhook_establish(sip_shutdown, sc);
539 	if (sc->sc_sdhook == NULL)
540 		printf("%s: WARNING: unable to establish shutdown hook\n",
541 		    sc->sc_dev.dv_xname);
542 	return;
543 
544 	/*
545 	 * Free any resources we've allocated during the failed attach
546 	 * attempt.  Do this in reverse order and fall through.
547 	 */
548  fail_5:
549 	for (i = 0; i < SIP_NRXDESC; i++) {
550 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
551 			bus_dmamap_destroy(sc->sc_dmat,
552 			    sc->sc_rxsoft[i].rxs_dmamap);
553 	}
554  fail_4:
555 	for (i = 0; i < SIP_TXQUEUELEN; i++) {
556 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
557 			bus_dmamap_destroy(sc->sc_dmat,
558 			    sc->sc_txsoft[i].txs_dmamap);
559 	}
560 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
561  fail_3:
562 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
563  fail_2:
564 	bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_control_data,
565 	    sizeof(struct sip_control_data));
566  fail_1:
567 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
568  fail_0:
569 	return;
570 }
571 
572 /*
573  * sip_shutdown:
574  *
575  *	Make sure the interface is stopped at reboot time.
576  */
577 void
578 sip_shutdown(arg)
579 	void *arg;
580 {
581 	struct sip_softc *sc = arg;
582 
583 	sip_stop(sc, 1);
584 }
585 
586 /*
587  * sip_start:		[ifnet interface function]
588  *
589  *	Start packet transmission on the interface.
590  */
591 void
592 sip_start(ifp)
593 	struct ifnet *ifp;
594 {
595 	struct sip_softc *sc = ifp->if_softc;
596 	struct mbuf *m0, *m;
597 	struct sip_txsoft *txs;
598 	bus_dmamap_t dmamap;
599 	int error, firsttx, nexttx, lasttx, ofree, seg;
600 
601 	/*
602 	 * If we've been told to pause, don't transmit any more packets.
603 	 */
604 	if (sc->sc_flags & SIPF_PAUSED)
605 		ifp->if_flags |= IFF_OACTIVE;
606 
607 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
608 		return;
609 
610 	/*
611 	 * Remember the previous number of free descriptors and
612 	 * the first descriptor we'll use.
613 	 */
614 	ofree = sc->sc_txfree;
615 	firsttx = sc->sc_txnext;
616 
617 	/*
618 	 * Loop through the send queue, setting up transmit descriptors
619 	 * until we drain the queue, or use up all available transmit
620 	 * descriptors.
621 	 */
622 	while ((txs = SIMPLEQ_FIRST(&sc->sc_txfreeq)) != NULL &&
623 	       sc->sc_txfree != 0) {
624 		/*
625 		 * Grab a packet off the queue.
626 		 */
627 		IF_DEQUEUE(&ifp->if_snd, m0);
628 		if (m0 == NULL)
629 			break;
630 
631 		dmamap = txs->txs_dmamap;
632 
633 		/*
634 		 * Load the DMA map.  If this fails, the packet either
635 		 * didn't fit in the alloted number of segments, or we
636 		 * were short on resources.  In this case, we'll copy
637 		 * and try again.
638 		 */
639 		if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
640 		    BUS_DMA_NOWAIT) != 0) {
641 			MGETHDR(m, M_DONTWAIT, MT_DATA);
642 			if (m == NULL) {
643 				printf("%s: unable to allocate Tx mbuf\n",
644 				    sc->sc_dev.dv_xname);
645 				IF_PREPEND(&ifp->if_snd, m0);
646 				break;
647 			}
648 			if (m0->m_pkthdr.len > MHLEN) {
649 				MCLGET(m, M_DONTWAIT);
650 				if ((m->m_flags & M_EXT) == 0) {
651 					printf("%s: unable to allocate Tx "
652 					    "cluster\n", sc->sc_dev.dv_xname);
653 					m_freem(m);
654 					IF_PREPEND(&ifp->if_snd, m0);
655 					break;
656 				}
657 			}
658 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, caddr_t));
659 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
660 			m_freem(m0);
661 			m0 = m;
662 			error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
663 			    m0, BUS_DMA_NOWAIT);
664 			if (error) {
665 				printf("%s: unable to load Tx buffer, "
666 				    "error = %d\n", sc->sc_dev.dv_xname, error);
667 				IF_PREPEND(&ifp->if_snd, m0);
668 				break;
669 			}
670 		}
671 
672 		/*
673 		 * Ensure we have enough descriptors free to describe
674 		 * the packet.
675 		 */
676 		if (dmamap->dm_nsegs > sc->sc_txfree) {
677 			/*
678 			 * Not enough free descriptors to transmit this
679 			 * packet.  We haven't committed anything yet,
680 			 * so just unload the DMA map, put the packet
681 			 * back on the queue, and punt.  Notify the upper
682 			 * layer that there are not more slots left.
683 			 *
684 			 * XXX We could allocate an mbuf and copy, but
685 			 * XXX is it worth it?
686 			 */
687 			ifp->if_flags |= IFF_OACTIVE;
688 			bus_dmamap_unload(sc->sc_dmat, dmamap);
689 			IF_PREPEND(&ifp->if_snd, m0);
690 			break;
691 		}
692 
693 		/*
694 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
695 		 */
696 
697 		/* Sync the DMA map. */
698 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
699 		    BUS_DMASYNC_PREWRITE);
700 
701 		/*
702 		 * Initialize the transmit descriptors.
703 		 */
704 		for (nexttx = sc->sc_txnext, seg = 0;
705 		     seg < dmamap->dm_nsegs;
706 		     seg++, nexttx = SIP_NEXTTX(nexttx)) {
707 			/*
708 			 * If this is the first descriptor we're
709 			 * enqueueing, don't set the OWN bit just
710 			 * yet.  That could cause a race condition.
711 			 * We'll do it below.
712 			 */
713 			sc->sc_txdescs[nexttx].sipd_bufptr =
714 			    dmamap->dm_segs[seg].ds_addr;
715 			sc->sc_txdescs[nexttx].sipd_cmdsts =
716 			    (nexttx == firsttx ? 0 : CMDSTS_OWN) |
717 			    CMDSTS_MORE | dmamap->dm_segs[seg].ds_len;
718 			lasttx = nexttx;
719 		}
720 
721 		/* Clear the MORE bit on the last segment. */
722 		sc->sc_txdescs[lasttx].sipd_cmdsts &= ~CMDSTS_MORE;
723 
724 		/* Sync the descriptors we're using. */
725 		SIP_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
726 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
727 
728 		/*
729 		 * Store a pointer to the packet so we can free it later,
730 		 * and remember what txdirty will be once the packet is
731 		 * done.
732 		 */
733 		txs->txs_mbuf = m0;
734 		txs->txs_firstdesc = sc->sc_txnext;
735 		txs->txs_lastdesc = lasttx;
736 
737 		/* Advance the tx pointer. */
738 		sc->sc_txfree -= dmamap->dm_nsegs;
739 		sc->sc_txnext = nexttx;
740 
741 		SIMPLEQ_REMOVE_HEAD(&sc->sc_txfreeq, txs, txs_q);
742 		SIMPLEQ_INSERT_TAIL(&sc->sc_txdirtyq, txs, txs_q);
743 
744 #if NBPFILTER > 0
745 		/*
746 		 * Pass the packet to any BPF listeners.
747 		 */
748 		if (ifp->if_bpf)
749 			bpf_mtap(ifp->if_bpf, m0);
750 #endif /* NBPFILTER > 0 */
751 	}
752 
753 	if (txs == NULL || sc->sc_txfree == 0) {
754 		/* No more slots left; notify upper layer. */
755 		ifp->if_flags |= IFF_OACTIVE;
756 	}
757 
758 	if (sc->sc_txfree != ofree) {
759 		/*
760 		 * Cause a descriptor interrupt to happen on the
761 		 * last packet we enqueued.
762 		 */
763 		sc->sc_txdescs[lasttx].sipd_cmdsts |= CMDSTS_INTR;
764 		SIP_CDTXSYNC(sc, lasttx, 1,
765 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
766 
767 		/*
768 		 * The entire packet chain is set up.  Give the
769 		 * first descrptor to the chip now.
770 		 */
771 		sc->sc_txdescs[firsttx].sipd_cmdsts |= CMDSTS_OWN;
772 		SIP_CDTXSYNC(sc, firsttx, 1,
773 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
774 
775 		/* Start the transmit process. */
776 		if ((bus_space_read_4(sc->sc_st, sc->sc_sh, SIP_CR) &
777 		     CR_TXE) == 0) {
778 			bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_TXDP,
779 			    SIP_CDTXADDR(sc, firsttx));
780 			bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_CR, CR_TXE);
781 		}
782 
783 		/* Set a watchdog timer in case the chip flakes out. */
784 		ifp->if_timer = 5;
785 	}
786 }
787 
788 /*
789  * sip_watchdog:	[ifnet interface function]
790  *
791  *	Watchdog timer handler.
792  */
793 void
794 sip_watchdog(ifp)
795 	struct ifnet *ifp;
796 {
797 	struct sip_softc *sc = ifp->if_softc;
798 
799 	/*
800 	 * The chip seems to ignore the CMDSTS_INTR bit sometimes!
801 	 * If we get a timeout, try and sweep up transmit descriptors.
802 	 * If we manage to sweep them all up, ignore the lack of
803 	 * interrupt.
804 	 */
805 	sip_txintr(sc);
806 
807 	if (sc->sc_txfree != SIP_NTXDESC) {
808 		printf("%s: device timeout\n", sc->sc_dev.dv_xname);
809 		ifp->if_oerrors++;
810 
811 		/* Reset the interface. */
812 		(void) sip_init(sc);
813 	} else if (ifp->if_flags & IFF_DEBUG)
814 		printf("%s: recovered from device timeout\n",
815 		    sc->sc_dev.dv_xname);
816 
817 	/* Try to get more packets going. */
818 	sip_start(ifp);
819 }
820 
821 /*
822  * sip_ioctl:		[ifnet interface function]
823  *
824  *	Handle control requests from the operator.
825  */
826 int
827 sip_ioctl(ifp, cmd, data)
828 	struct ifnet *ifp;
829 	u_long cmd;
830 	caddr_t data;
831 {
832 	struct sip_softc *sc = ifp->if_softc;
833 	struct ifreq *ifr = (struct ifreq *)data;
834 	struct ifaddr *ifa = (struct ifaddr *)data;
835 	int s, error = 0;
836 
837 	s = splnet();
838 
839 	switch (cmd) {
840 	case SIOCSIFADDR:
841 		ifp->if_flags |= IFF_UP;
842 
843 		switch (ifa->ifa_addr->sa_family) {
844 #ifdef INET
845 		case AF_INET:
846 			if ((error = sip_init(sc)) != 0)
847 				break;
848 			arp_ifinit(ifp, ifa);
849 			break;
850 #endif /* INET */
851 #ifdef NS
852 		case AF_NS:
853 		    {
854 			struct ns_addr *ina = &IA_SNS(ifa)->sns_addr;
855 
856 			if (ns_nullhost(*ina))
857 				ina->x_host = *(union ns_host *)
858 				    LLADDR(ifp->if_sadl);
859 			else
860 				memcpy(LLADDR(ifp->if_sadl),
861 				    ina->x_host.c_host, ifp->if_addrlen);
862 			error = sip_init(sc);
863 			break;
864 		    }
865 #endif /* NS */
866 		default:
867 			error = sip_init(sc);
868 			break;
869 		}
870 		break;
871 
872 	case SIOCSIFMTU:
873 		if (ifr->ifr_mtu > ETHERMTU)
874 			error = EINVAL;
875 		else
876 			ifp->if_mtu = ifr->ifr_mtu;
877 		break;
878 
879 	case SIOCSIFFLAGS:
880 		if ((ifp->if_flags & IFF_UP) == 0 &&
881 		    (ifp->if_flags & IFF_RUNNING) != 0) {
882 			/*
883 			 * If interface is marked down and it is running, then
884 			 * stop it.
885 			 */
886 			sip_stop(sc, 1);
887 		} else if ((ifp->if_flags & IFF_UP) != 0 &&
888 			   (ifp->if_flags & IFF_RUNNING) == 0) {
889 			/*
890 			 * If interfase it marked up and it is stopped, then
891 			 * start it.
892 			 */
893 			error = sip_init(sc);
894 		} else if ((ifp->if_flags & IFF_UP) != 0) {
895 			/*
896 			 * Reset the interface to pick up changes in any other
897 			 * flags that affect the hardware state.
898 			 */
899 			error = sip_init(sc);
900 		}
901 		break;
902 
903 	case SIOCADDMULTI:
904 	case SIOCDELMULTI:
905 		error = (cmd == SIOCADDMULTI) ?
906 		    ether_addmulti(ifr, &sc->sc_ethercom) :
907 		    ether_delmulti(ifr, &sc->sc_ethercom);
908 
909 		if (error == ENETRESET) {
910 			/*
911 			 * Multicast list has changed; set the hardware filter
912 			 * accordingly.
913 			 */
914 			sip_set_filter(sc);
915 			error = 0;
916 		}
917 		break;
918 
919 	case SIOCSIFMEDIA:
920 	case SIOCGIFMEDIA:
921 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
922 		break;
923 
924 	default:
925 		error = EINVAL;
926 		break;
927 	}
928 
929 	/* Try to get more packets going. */
930 	sip_start(ifp);
931 
932 	splx(s);
933 	return (error);
934 }
935 
936 /*
937  * sip_intr:
938  *
939  *	Interrupt service routine.
940  */
941 int
942 sip_intr(arg)
943 	void *arg;
944 {
945 	struct sip_softc *sc = arg;
946 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
947 	u_int32_t isr;
948 	int handled = 0;
949 
950 	for (;;) {
951 		/* Reading clears interrupt. */
952 		isr = bus_space_read_4(sc->sc_st, sc->sc_sh, SIP_ISR);
953 		if ((isr & sc->sc_imr) == 0)
954 			break;
955 
956 		handled = 1;
957 
958 		if (isr & (ISR_RXORN|ISR_RXIDLE|ISR_RXDESC)) {
959 			/* Grab any new packets. */
960 			sip_rxintr(sc);
961 
962 			if (isr & ISR_RXORN) {
963 				printf("%s: receive FIFO overrun\n",
964 				    sc->sc_dev.dv_xname);
965 
966 				/* XXX adjust rx_drain_thresh? */
967 			}
968 
969 			if (isr & ISR_RXIDLE) {
970 				printf("%s: receive ring overrun\n",
971 				    sc->sc_dev.dv_xname);
972 
973 				/* Get the receive process going again. */
974 				bus_space_write_4(sc->sc_st, sc->sc_sh,
975 				    SIP_RXDP, SIP_CDRXADDR(sc, sc->sc_rxptr));
976 				bus_space_write_4(sc->sc_st, sc->sc_sh,
977 				    SIP_CR, CR_RXE);
978 			}
979 		}
980 
981 		if (isr & (ISR_TXURN|ISR_TXDESC)) {
982 			/* Sweep up transmit descriptors. */
983 			sip_txintr(sc);
984 
985 			if (isr & ISR_TXURN) {
986 				u_int32_t thresh;
987 
988 				printf("%s: transmit FIFO underrun",
989 				    sc->sc_dev.dv_xname);
990 
991 				thresh = sc->sc_tx_drain_thresh + 1;
992 				if (thresh <= TXCFG_DRTH &&
993 				    (thresh * 32) <= (SIP_TXFIFO_SIZE -
994 				     (sc->sc_tx_fill_thresh * 32))) {
995 					printf("; increasing Tx drain "
996 					    "threshold to %u bytes\n",
997 					    thresh * 32);
998 					sc->sc_tx_drain_thresh = thresh;
999 					(void) sip_init(sc);
1000 				} else {
1001 					(void) sip_init(sc);
1002 					printf("\n");
1003 				}
1004 			}
1005 		}
1006 
1007 		if (sc->sc_imr & (ISR_PAUSE_END|ISR_PAUSE_ST)) {
1008 			if (isr & ISR_PAUSE_ST) {
1009 				sc->sc_flags |= SIPF_PAUSED;
1010 				ifp->if_flags |= IFF_OACTIVE;
1011 			}
1012 			if (isr & ISR_PAUSE_END) {
1013 				sc->sc_flags &= ~SIPF_PAUSED;
1014 				ifp->if_flags &= ~IFF_OACTIVE;
1015 			}
1016 		}
1017 
1018 		if (isr & ISR_HIBERR) {
1019 #define	PRINTERR(bit, str)						\
1020 			if (isr & (bit))				\
1021 				printf("%s: %s\n", sc->sc_dev.dv_xname, str)
1022 			PRINTERR(ISR_DPERR, "parity error");
1023 			PRINTERR(ISR_SSERR, "system error");
1024 			PRINTERR(ISR_RMABT, "master abort");
1025 			PRINTERR(ISR_RTABT, "target abort");
1026 			PRINTERR(ISR_RXSOVR, "receive status FIFO overrun");
1027 			(void) sip_init(sc);
1028 #undef PRINTERR
1029 		}
1030 	}
1031 
1032 	/* Try to get more packets going. */
1033 	sip_start(ifp);
1034 
1035 	return (handled);
1036 }
1037 
1038 /*
1039  * sip_txintr:
1040  *
1041  *	Helper; handle transmit interrupts.
1042  */
1043 void
1044 sip_txintr(sc)
1045 	struct sip_softc *sc;
1046 {
1047 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1048 	struct sip_txsoft *txs;
1049 	u_int32_t cmdsts;
1050 
1051 	if ((sc->sc_flags & SIPF_PAUSED) == 0)
1052 		ifp->if_flags &= ~IFF_OACTIVE;
1053 
1054 	/*
1055 	 * Go through our Tx list and free mbufs for those
1056 	 * frames which have been transmitted.
1057 	 */
1058 	while ((txs = SIMPLEQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1059 		SIP_CDTXSYNC(sc, txs->txs_firstdesc, txs->txs_dmamap->dm_nsegs,
1060 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1061 
1062 		cmdsts = sc->sc_txdescs[txs->txs_lastdesc].sipd_cmdsts;
1063 		if (cmdsts & CMDSTS_OWN)
1064 			break;
1065 
1066 		SIMPLEQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs, txs_q);
1067 
1068 		sc->sc_txfree += txs->txs_dmamap->dm_nsegs;
1069 
1070 		bus_dmamap_sync(sc->sc_dmat, txs->txs_dmamap,
1071 		    0, txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
1072 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1073 		m_freem(txs->txs_mbuf);
1074 		txs->txs_mbuf = NULL;
1075 
1076 		SIMPLEQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1077 
1078 		/*
1079 		 * Check for errors and collisions.
1080 		 */
1081 		if (cmdsts &
1082 		    (CMDSTS_Tx_TXA|CMDSTS_Tx_TFU|CMDSTS_Tx_ED|CMDSTS_Tx_EC)) {
1083 			if (ifp->if_flags & IFF_DEBUG) {
1084 				if (CMDSTS_Tx_ED)
1085 					printf("%s: excessive deferral\n",
1086 					    sc->sc_dev.dv_xname);
1087 				if (CMDSTS_Tx_EC) {
1088 					printf("%s: excessive collisions\n",
1089 					    sc->sc_dev.dv_xname);
1090 					ifp->if_collisions += 16;
1091 				}
1092 			}
1093 		} else {
1094 			/* Packet was transmitted successfully. */
1095 			ifp->if_opackets++;
1096 			ifp->if_collisions += CMDSTS_COLLISIONS(cmdsts);
1097 		}
1098 	}
1099 
1100 	/*
1101 	 * If there are no more pending transmissions, cancel the watchdog
1102 	 * timer.
1103 	 */
1104 	if (txs == NULL)
1105 		ifp->if_timer = 0;
1106 }
1107 
1108 /*
1109  * sip_rxintr:
1110  *
1111  *	Helper; handle receive interrupts.
1112  */
1113 void
1114 sip_rxintr(sc)
1115 	struct sip_softc *sc;
1116 {
1117 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1118 	struct ether_header *eh;
1119 	struct sip_rxsoft *rxs;
1120 	struct mbuf *m;
1121 	u_int32_t cmdsts;
1122 	int i, len;
1123 
1124 	for (i = sc->sc_rxptr;; i = SIP_NEXTRX(i)) {
1125 		rxs = &sc->sc_rxsoft[i];
1126 
1127 		SIP_CDRXSYNC(sc, i, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1128 
1129 		cmdsts = sc->sc_rxdescs[i].sipd_cmdsts;
1130 
1131 		/*
1132 		 * NOTE: OWN is set if owned by _consumer_.  We're the
1133 		 * consumer of the receive ring, so if the bit is clear,
1134 		 * we have processed all of the packets.
1135 		 */
1136 		if ((cmdsts & CMDSTS_OWN) == 0) {
1137 			/*
1138 			 * We have processed all of the receive buffers.
1139 			 */
1140 			break;
1141 		}
1142 
1143 		/*
1144 		 * If any collisions were seen on the wire, count one.
1145 		 */
1146 		if (cmdsts & CMDSTS_Rx_COL)
1147 			ifp->if_collisions++;
1148 
1149 		/*
1150 		 * If an error occurred, update stats, clear the status
1151 		 * word, and leave the packet buffer in place.  It will
1152 		 * simply be reused the next time the ring comes around.
1153 		 */
1154 		if (cmdsts & (CMDSTS_Rx_RXA|CMDSTS_Rx_LONG|CMDSTS_Rx_RUNT|
1155 		    CMDSTS_Rx_ISE|CMDSTS_Rx_CRCE|CMDSTS_Rx_FAE)) {
1156 			ifp->if_ierrors++;
1157 			if ((cmdsts & CMDSTS_Rx_RXA) != 0 &&
1158 			    (cmdsts & CMDSTS_Rx_RXO) == 0) {
1159 				/* Receive overrun handled elsewhere. */
1160 				printf("%s: receive descriptor error\n",
1161 				    sc->sc_dev.dv_xname);
1162 			}
1163 #define	PRINTERR(bit, str)						\
1164 			if (cmdsts & (bit))				\
1165 				printf("%s: %s\n", sc->sc_dev.dv_xname, str)
1166 			PRINTERR(CMDSTS_Rx_LONG, "packet too long");
1167 			PRINTERR(CMDSTS_Rx_RUNT, "runt packet");
1168 			PRINTERR(CMDSTS_Rx_ISE, "invalid symbol error");
1169 			PRINTERR(CMDSTS_Rx_CRCE, "CRC error");
1170 			PRINTERR(CMDSTS_Rx_FAE, "frame alignment error");
1171 #undef PRINTERR
1172 			SIP_INIT_RXDESC(sc, i);
1173 			continue;
1174 		}
1175 
1176 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1177 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1178 
1179 		/*
1180 		 * No errors; receive the packet.  Note, the SiS 900
1181 		 * includes the CRC with every packet; trim it.
1182 		 */
1183 		len = CMDSTS_SIZE(cmdsts) - ETHER_CRC_LEN;
1184 
1185 #ifdef __NO_STRICT_ALIGNMENT
1186 		/*
1187 		 * If the packet is small enough to fit in a
1188 		 * single header mbuf, allocate one and copy
1189 		 * the data into it.  This greatly reduces
1190 		 * memory consumption when we receive lots
1191 		 * of small packets.
1192 		 *
1193 		 * Otherwise, we add a new buffer to the receive
1194 		 * chain.  If this fails, we drop the packet and
1195 		 * recycle the old buffer.
1196 		 */
1197 		if (sip_copy_small != 0 && len <= MHLEN) {
1198 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1199 			if (m == NULL)
1200 				goto dropit;
1201 			memcpy(mtod(m, caddr_t),
1202 			    mtod(rxs->rxs_mbuf, caddr_t), len);
1203 			SIP_INIT_RXDESC(sc, i);
1204 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1205 			    rxs->rxs_dmamap->dm_mapsize,
1206 			    BUS_DMASYNC_PREREAD);
1207 		} else {
1208 			m = rxs->rxs_mbuf;
1209 			if (sip_add_rxbuf(sc, i) != 0) {
1210  dropit:
1211 				ifp->if_ierrors++;
1212 				SIP_INIT_RXDESC(sc, i);
1213 				bus_dmamap_sync(sc->sc_dmat,
1214 				    rxs->rxs_dmamap, 0,
1215 				    rxs->rxs_dmamap->dm_mapsize,
1216 				    BUS_DMASYNC_PREREAD);
1217 				continue;
1218 			}
1219 		}
1220 #else
1221 		/*
1222 		 * The SiS 900's receive buffers must be 4-byte aligned.
1223 		 * But this means that the data after the Ethernet header
1224 		 * is misaligned.  We must allocate a new buffer and
1225 		 * copy the data, shifted forward 2 bytes.
1226 		 */
1227 		MGETHDR(m, M_DONTWAIT, MT_DATA);
1228 		if (m == NULL) {
1229  dropit:
1230 			ifp->if_ierrors++;
1231 			SIP_INIT_RXDESC(sc, i);
1232 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1233 			    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1234 			continue;
1235 		}
1236 		if (len > (MHLEN - 2)) {
1237 			MCLGET(m, M_DONTWAIT);
1238 			if ((m->m_flags & M_EXT) == 0) {
1239 				m_freem(m);
1240 				goto dropit;
1241 			}
1242 		}
1243 		m->m_data += 2;
1244 
1245 		/*
1246 		 * Note that we use clusters for incoming frames, so the
1247 		 * buffer is virtually contiguous.
1248 		 */
1249 		memcpy(mtod(m, caddr_t), mtod(rxs->rxs_mbuf, caddr_t), len);
1250 
1251 		/* Allow the receive descriptor to continue using its mbuf. */
1252 		SIP_INIT_RXDESC(sc, i);
1253 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1254 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1255 #endif /* __NO_STRICT_ALIGNMENT */
1256 
1257 		ifp->if_ipackets++;
1258 		eh = mtod(m, struct ether_header *);
1259 		m->m_pkthdr.rcvif = ifp;
1260 		m->m_pkthdr.len = m->m_len = len;
1261 
1262 #if NBPFILTER > 0
1263 		/*
1264 		 * Pass this up to any BPF listeners, but only
1265 		 * pass if up the stack if it's for us.
1266 		 */
1267 		if (ifp->if_bpf) {
1268 			bpf_mtap(ifp->if_bpf, m);
1269 			if ((ifp->if_flags & IFF_PROMISC) != 0 &&
1270 			    (cmdsts & CMDSTS_Rx_DEST) == CMDSTS_Rx_DEST_REJ) {
1271 				m_freem(m);
1272 				continue;
1273 			}
1274 		}
1275 #endif /* NBPFILTER > 0 */
1276 
1277 		/* Pass it on. */
1278 		(*ifp->if_input)(ifp, m);
1279 	}
1280 
1281 	/* Update the receive pointer. */
1282 	sc->sc_rxptr = i;
1283 }
1284 
1285 /*
1286  * sip_tick:
1287  *
1288  *	One second timer, used to tick the MII.
1289  */
1290 void
1291 sip_tick(arg)
1292 	void *arg;
1293 {
1294 	struct sip_softc *sc = arg;
1295 	int s;
1296 
1297 	s = splnet();
1298 	mii_tick(&sc->sc_mii);
1299 	splx(s);
1300 
1301 	timeout(sip_tick, sc, hz);
1302 }
1303 
1304 /*
1305  * sip_reset:
1306  *
1307  *	Perform a soft reset on the SiS 900.
1308  */
1309 void
1310 sip_reset(sc)
1311 	struct sip_softc *sc;
1312 {
1313 	bus_space_tag_t st = sc->sc_st;
1314 	bus_space_handle_t sh = sc->sc_sh;
1315 	int i;
1316 
1317 	bus_space_write_4(st, sh, SIP_CR, CR_RST);
1318 
1319 	for (i = 0; i < 1000; i++) {
1320 		if ((bus_space_read_4(st, sh, SIP_ISR) &
1321 		     (ISR_TXRCMP|ISR_RXRCMP)) == (ISR_TXRCMP|ISR_RXRCMP))
1322 			return;
1323 		delay(2);
1324 	}
1325 
1326 	printf("%s: reset failed to complete\n", sc->sc_dev.dv_xname);
1327 }
1328 
1329 /*
1330  * sip_init:
1331  *
1332  *	Initialize the interface.  Must be called at splnet().
1333  */
1334 int
1335 sip_init(sc)
1336 	struct sip_softc *sc;
1337 {
1338 	bus_space_tag_t st = sc->sc_st;
1339 	bus_space_handle_t sh = sc->sc_sh;
1340 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1341 	struct sip_txsoft *txs;
1342 	struct sip_rxsoft *rxs;
1343 	struct sip_desc *sipd;
1344 	u_int32_t cfg;
1345 	int i, error = 0;
1346 
1347 	/*
1348 	 * Cancel any pending I/O.
1349 	 */
1350 	sip_stop(sc, 0);
1351 
1352 	/*
1353 	 * Reset the chip to a known state.
1354 	 */
1355 	sip_reset(sc);
1356 
1357 	/*
1358 	 * Initialize the transmit descriptor ring.
1359 	 */
1360 	for (i = 0; i < SIP_NTXDESC; i++) {
1361 		sipd = &sc->sc_txdescs[i];
1362 		memset(sipd, 0, sizeof(struct sip_desc));
1363 		sipd->sipd_link = SIP_CDTXADDR(sc, SIP_NEXTTX(i));
1364 	}
1365 	SIP_CDTXSYNC(sc, 0, SIP_NTXDESC,
1366 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1367 	sc->sc_txfree = SIP_NTXDESC;
1368 	sc->sc_txnext = 0;
1369 
1370 	/*
1371 	 * Initialize the transmit job descriptors.
1372 	 */
1373 	SIMPLEQ_INIT(&sc->sc_txfreeq);
1374 	SIMPLEQ_INIT(&sc->sc_txdirtyq);
1375 	for (i = 0; i < SIP_TXQUEUELEN; i++) {
1376 		txs = &sc->sc_txsoft[i];
1377 		txs->txs_mbuf = NULL;
1378 		SIMPLEQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1379 	}
1380 
1381 	/*
1382 	 * Initialize the receive descriptor and receive job
1383 	 * descriptor rings.
1384 	 */
1385 	for (i = 0; i < SIP_NRXDESC; i++) {
1386 		rxs = &sc->sc_rxsoft[i];
1387 		if (rxs->rxs_mbuf == NULL) {
1388 			if ((error = sip_add_rxbuf(sc, i)) != 0) {
1389 				printf("%s: unable to allocate or map rx "
1390 				    "buffer %d, error = %d\n",
1391 				    sc->sc_dev.dv_xname, i, error);
1392 				/*
1393 				 * XXX Should attempt to run with fewer receive
1394 				 * XXX buffers instead of just failing.
1395 				 */
1396 				sip_rxdrain(sc);
1397 				goto out;
1398 			}
1399 		}
1400 	}
1401 	sc->sc_rxptr = 0;
1402 
1403 	/*
1404 	 * Initialize the configuration register: aggressive PCI
1405 	 * bus request algorithm, default backoff, default OW timer,
1406 	 * default parity error detection.
1407 	 */
1408 	cfg = 0;
1409 #if BYTE_ORDER == BIG_ENDIAN
1410 	/*
1411 	 * ...descriptors in big-endian mode.
1412 	 */
1413 	cfg |= CFG_BEM;
1414 #endif
1415 	bus_space_write_4(st, sh, SIP_CFG, cfg);
1416 
1417 	/*
1418 	 * Initialize the transmit fill and drain thresholds if
1419 	 * we have never done so.
1420 	 */
1421 	if (sc->sc_tx_fill_thresh == 0) {
1422 		/*
1423 		 * XXX This value should be tuned.  This is the
1424 		 * minimum (32 bytes), and we may be able to
1425 		 * improve performance by increasing it.
1426 		 */
1427 		sc->sc_tx_fill_thresh = 1;
1428 	}
1429 	if (sc->sc_tx_drain_thresh == 0) {
1430 		/*
1431 		 * Start at a drain threshold of 128 bytes.  We will
1432 		 * increase it if a DMA underrun occurs.
1433 		 *
1434 		 * XXX The minimum value of this variable should be
1435 		 * tuned.  We may be able to improve performance
1436 		 * by starting with a lower value.  That, however,
1437 		 * may trash the first few outgoing packets if the
1438 		 * PCI bus is saturated.
1439 		 */
1440 		sc->sc_tx_drain_thresh = 4;
1441 	}
1442 
1443 	/*
1444 	 * Initialize the prototype TXCFG register.
1445 	 */
1446 	sc->sc_txcfg = TXCFG_ATP | TXCFG_MXDMA_512 |
1447 	    (sc->sc_tx_fill_thresh << TXCFG_FLTH_SHIFT) |
1448 	    sc->sc_tx_drain_thresh;
1449 	bus_space_write_4(st, sh, SIP_TXCFG, sc->sc_txcfg);
1450 
1451 	/*
1452 	 * Initialize the receive drain threshold if we have never
1453 	 * done so.
1454 	 */
1455 	if (sc->sc_rx_drain_thresh == 0) {
1456 		/*
1457 		 * XXX This value should be tuned.  This is set to the
1458 		 * maximum of 248 bytes, and we may be able to improve
1459 		 * performance by decreasing it (although we should never
1460 		 * set this value lower than 2; 14 bytes are required to
1461 		 * filter the packet).
1462 		 */
1463 		sc->sc_rx_drain_thresh = RXCFG_DRTH >> RXCFG_DRTH_SHIFT;
1464 	}
1465 
1466 	/*
1467 	 * Initialize the prototype RXCFG register.
1468 	 */
1469 	sc->sc_rxcfg = RXCFG_MXDMA_512 |
1470 	    (sc->sc_rx_drain_thresh << RXCFG_DRTH_SHIFT);
1471 	bus_space_write_4(st, sh, SIP_RXCFG, sc->sc_rxcfg);
1472 
1473 	/* Set up the receive filter. */
1474 	sip_set_filter(sc);
1475 
1476 	/*
1477 	 * Give the transmit and receive rings to the chip.
1478 	 */
1479 	bus_space_write_4(st, sh, SIP_TXDP, SIP_CDTXADDR(sc, sc->sc_txnext));
1480 	bus_space_write_4(st, sh, SIP_RXDP, SIP_CDRXADDR(sc, sc->sc_rxptr));
1481 
1482 	/*
1483 	 * Initialize the interrupt mask.
1484 	 */
1485 	sc->sc_imr = ISR_DPERR|ISR_SSERR|ISR_RMABT|ISR_RTABT|ISR_RXSOVR|
1486 	    ISR_TXURN|ISR_TXDESC|ISR_RXORN|ISR_RXIDLE|ISR_RXDESC;
1487 	bus_space_write_4(st, sh, SIP_IMR, sc->sc_imr);
1488 
1489 	/*
1490 	 * Set the current media.  Do this after initializing the prototype
1491 	 * IMR, since sip_mii_statchg() modifies the IMR for 802.3x flow
1492 	 * control.
1493 	 */
1494 	mii_mediachg(&sc->sc_mii);
1495 
1496 	/*
1497 	 * Enable interrupts.
1498 	 */
1499 	bus_space_write_4(st, sh, SIP_IER, IER_IE);
1500 
1501 	/*
1502 	 * Start the transmit and receive processes.
1503 	 */
1504 	bus_space_write_4(st, sh, SIP_CR, CR_RXE | CR_TXE);
1505 
1506 	/*
1507 	 * Start the one second MII clock.
1508 	 */
1509 	timeout(sip_tick, sc, hz);
1510 
1511 	/*
1512 	 * ...all done!
1513 	 */
1514 	ifp->if_flags |= IFF_RUNNING;
1515 	ifp->if_flags &= ~IFF_OACTIVE;
1516 
1517  out:
1518 	if (error)
1519 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
1520 	return (error);
1521 }
1522 
1523 /*
1524  * sip_drain:
1525  *
1526  *	Drain the receive queue.
1527  */
1528 void
1529 sip_rxdrain(sc)
1530 	struct sip_softc *sc;
1531 {
1532 	struct sip_rxsoft *rxs;
1533 	int i;
1534 
1535 	for (i = 0; i < SIP_NRXDESC; i++) {
1536 		rxs = &sc->sc_rxsoft[i];
1537 		if (rxs->rxs_mbuf != NULL) {
1538 			bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1539 			m_freem(rxs->rxs_mbuf);
1540 			rxs->rxs_mbuf = NULL;
1541 		}
1542 	}
1543 }
1544 
1545 /*
1546  * sip_stop:
1547  *
1548  *	Stop transmission on the interface.
1549  */
1550 void
1551 sip_stop(sc, drain)
1552 	struct sip_softc *sc;
1553 {
1554 	bus_space_tag_t st = sc->sc_st;
1555 	bus_space_handle_t sh = sc->sc_sh;
1556 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1557 	struct sip_txsoft *txs;
1558 	u_int32_t cmdsts = 0;		/* DEBUG */
1559 
1560 	/*
1561 	 * Stop the one second clock.
1562 	 */
1563 	untimeout(sip_tick, sc);
1564 
1565 	/*
1566 	 * Disable interrupts.
1567 	 */
1568 	bus_space_write_4(st, sh, SIP_IER, 0);
1569 
1570 	/*
1571 	 * Stop receiver and transmitter.
1572 	 */
1573 	bus_space_write_4(st, sh, SIP_CR, CR_RXD | CR_TXD);
1574 
1575 	/*
1576 	 * Release any queued transmit buffers.
1577 	 */
1578 	while ((txs = SIMPLEQ_FIRST(&sc->sc_txdirtyq)) != NULL) {
1579 		if ((ifp->if_flags & IFF_DEBUG) != 0 &&
1580 		    SIMPLEQ_NEXT(txs, txs_q) == NULL &&
1581 		    (sc->sc_txdescs[txs->txs_lastdesc].sipd_cmdsts &
1582 		     CMDSTS_INTR) == 0)
1583 			printf("%s: sip_stop: last descriptor does not "
1584 			    "have INTR bit set\n", sc->sc_dev.dv_xname);
1585 		SIMPLEQ_REMOVE_HEAD(&sc->sc_txdirtyq, txs, txs_q);
1586 #ifdef DIAGNOSTIC
1587 		if (txs->txs_mbuf == NULL) {
1588 			printf("%s: dirty txsoft with no mbuf chain\n",
1589 			    sc->sc_dev.dv_xname);
1590 			panic("sip_stop");
1591 		}
1592 #endif
1593 		cmdsts |=		/* DEBUG */
1594 		    sc->sc_txdescs[txs->txs_lastdesc].sipd_cmdsts;
1595 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1596 		m_freem(txs->txs_mbuf);
1597 		txs->txs_mbuf = NULL;
1598 		SIMPLEQ_INSERT_TAIL(&sc->sc_txfreeq, txs, txs_q);
1599 	}
1600 
1601 	if (drain) {
1602 		/*
1603 		 * Release the receive buffers.
1604 		 */
1605 		sip_rxdrain(sc);
1606 	}
1607 
1608 	/*
1609 	 * Mark the interface down and cancel the watchdog timer.
1610 	 */
1611 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1612 	ifp->if_timer = 0;
1613 
1614 	if ((ifp->if_flags & IFF_DEBUG) != 0 &&
1615 	    (cmdsts & CMDSTS_INTR) == 0 && sc->sc_txfree != SIP_NTXDESC)
1616 		printf("%s: sip_stop: no INTR bits set in dirty tx "
1617 		    "descriptors\n", sc->sc_dev.dv_xname);
1618 }
1619 
1620 /*
1621  * sip_read_eeprom:
1622  *
1623  *	Read data from the serial EEPROM.
1624  */
1625 void
1626 sip_read_eeprom(sc, word, wordcnt, data)
1627 	struct sip_softc *sc;
1628 	int word, wordcnt;
1629 	u_int16_t *data;
1630 {
1631 	bus_space_tag_t st = sc->sc_st;
1632 	bus_space_handle_t sh = sc->sc_sh;
1633 	u_int16_t reg;
1634 	int i, x;
1635 
1636 	for (i = 0; i < wordcnt; i++) {
1637 		/* Send CHIP SELECT. */
1638 		reg = EROMAR_EECS;
1639 		bus_space_write_4(st, sh, SIP_EROMAR, reg);
1640 
1641 		/* Shift in the READ opcode. */
1642 		for (x = 3; x > 0; x--) {
1643 			if (SIP_EEPROM_OPC_READ & (1 << (x - 1)))
1644 				reg |= EROMAR_EEDI;
1645 			else
1646 				reg &= ~EROMAR_EEDI;
1647 			bus_space_write_4(st, sh, SIP_EROMAR, reg);
1648 			bus_space_write_4(st, sh, SIP_EROMAR,
1649 			    reg | EROMAR_EESK);
1650 			delay(4);
1651 			bus_space_write_4(st, sh, SIP_EROMAR, reg);
1652 			delay(4);
1653 		}
1654 
1655 		/* Shift in address. */
1656 		for (x = 6; x > 0; x--) {
1657 			if ((word + i) & (1 << (x - 1)))
1658 				reg |= EROMAR_EEDI;
1659 			else
1660 				reg &= ~EROMAR_EEDI;
1661 			bus_space_write_4(st, sh, SIP_EROMAR, reg);
1662 			bus_space_write_4(st, sh, SIP_EROMAR,
1663 			    reg | EROMAR_EESK);
1664 			delay(4);
1665 			bus_space_write_4(st, sh, SIP_EROMAR, reg);
1666 			delay(4);
1667 		}
1668 
1669 		/* Shift out data. */
1670 		reg = EROMAR_EECS;
1671 		data[i] = 0;
1672 		for (x = 16; x > 0; x--) {
1673 			bus_space_write_4(st, sh, SIP_EROMAR,
1674 			    reg | EROMAR_EESK);
1675 			delay(4);
1676 			if (bus_space_read_4(st, sh, SIP_EROMAR) & EROMAR_EEDO)
1677 				data[i] |= (1 << (x - 1));
1678 			bus_space_write_4(st, sh, SIP_EROMAR, reg);
1679 		}
1680 
1681 		/* Clear CHIP SELECT. */
1682 		bus_space_write_4(st, sh, SIP_EROMAR, 0);
1683 		delay(4);
1684 	}
1685 }
1686 
1687 /*
1688  * sip_add_rxbuf:
1689  *
1690  *	Add a receive buffer to the indicated descriptor.
1691  */
1692 int
1693 sip_add_rxbuf(sc, idx)
1694 	struct sip_softc *sc;
1695 	int idx;
1696 {
1697 	struct sip_rxsoft *rxs = &sc->sc_rxsoft[idx];
1698 	struct mbuf *m;
1699 	int error;
1700 
1701 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1702 	if (m == NULL)
1703 		return (ENOBUFS);
1704 
1705 	MCLGET(m, M_DONTWAIT);
1706 	if ((m->m_flags & M_EXT) == 0) {
1707 		m_freem(m);
1708 		return (ENOBUFS);
1709 	}
1710 
1711 	if (rxs->rxs_mbuf != NULL)
1712 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1713 
1714 	rxs->rxs_mbuf = m;
1715 
1716 	error = bus_dmamap_load(sc->sc_dmat, rxs->rxs_dmamap,
1717 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL, BUS_DMA_NOWAIT);
1718 	if (error) {
1719 		printf("%s: can't load rx DMA map %d, error = %d\n",
1720 		    sc->sc_dev.dv_xname, idx, error);
1721 		panic("sip_add_rxbuf");		/* XXX */
1722 	}
1723 
1724 	bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1725 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1726 
1727 	SIP_INIT_RXDESC(sc, idx);
1728 
1729 	return (0);
1730 }
1731 
1732 /*
1733  * sip_set_filter:
1734  *
1735  *	Set up the receive filter.
1736  */
1737 void
1738 sip_set_filter(sc)
1739 	struct sip_softc *sc;
1740 {
1741 	bus_space_tag_t st = sc->sc_st;
1742 	bus_space_handle_t sh = sc->sc_sh;
1743 	struct ethercom *ec = &sc->sc_ethercom;
1744 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1745 	struct ether_multi *enm;
1746 	struct ether_multistep step;
1747 	u_int8_t *cp;
1748 	u_int32_t crc, mchash[8];
1749 	int len;
1750 	static const u_int32_t crctab[] = {
1751 		0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
1752 		0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
1753 		0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
1754 		0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
1755 	};
1756 
1757 	/*
1758 	 * Initialize the prototype RFCR.
1759 	 */
1760 	sc->sc_rfcr = RFCR_RFEN;
1761 	if (ifp->if_flags & IFF_BROADCAST)
1762 		sc->sc_rfcr |= RFCR_AAB;
1763 	if (ifp->if_flags & IFF_PROMISC) {
1764 		sc->sc_rfcr |= RFCR_AAP;
1765 		goto allmulti;
1766 	}
1767 
1768 	/*
1769 	 * Set up the multicast address filter by passing all multicast
1770 	 * addresses through a CRC generator, and then using the high-order
1771 	 * 6 bits as an index into the 128 bit multicast hash table (only
1772 	 * the lower 16 bits of each 32 bit multicast hash register are
1773 	 * valid).  The high order bits select the register, while the
1774 	 * rest of the bits select the bit within the register.
1775 	 */
1776 
1777 	memset(mchash, 0, sizeof(mchash));
1778 
1779 	ETHER_FIRST_MULTI(step, ec, enm);
1780 	while (enm != NULL) {
1781 		if (bcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
1782 			/*
1783 			 * We must listen to a range of multicast addresses.
1784 			 * For now, just accept all multicasts, rather than
1785 			 * trying to set only those filter bits needed to match
1786 			 * the range.  (At this time, the only use of address
1787 			 * ranges is for IP multicast routing, for which the
1788 			 * range is big enough to require all bits set.)
1789 			 */
1790 			goto allmulti;
1791 		}
1792 
1793 		cp = enm->enm_addrlo;
1794 		crc = 0xffffffff;
1795 		for (len = sizeof(enm->enm_addrlo); --len >= 0;) {
1796 			crc ^= *cp++;
1797 			crc = (crc >> 4) ^ crctab[crc & 0xf];
1798 			crc = (crc >> 4) ^ crctab[crc & 0xf];
1799 		}
1800 		/* Just want the 7 most significant bits. */
1801 		crc >>= 25;
1802 
1803 		/* Set the corresponding bit in the hash table. */
1804 		mchash[crc >> 4] |= 1 << (crc & 0xf);
1805 
1806 		ETHER_NEXT_MULTI(step, enm);
1807 	}
1808 
1809 	ifp->if_flags &= ~IFF_ALLMULTI;
1810 	goto setit;
1811 
1812  allmulti:
1813 	ifp->if_flags |= IFF_ALLMULTI;
1814 	sc->sc_rfcr |= RFCR_AAM;
1815 
1816  setit:
1817 #define	FILTER_EMIT(addr, data)						\
1818 	bus_space_write_4(st, sh, SIP_RFCR, (addr));			\
1819 	bus_space_write_4(st, sh, SIP_RFDR, (data))
1820 
1821 	/*
1822 	 * Disable receive filter, and program the node address.
1823 	 */
1824 	cp = LLADDR(ifp->if_sadl);
1825 	FILTER_EMIT(RFCR_RFADDR_NODE0, (cp[1] << 8) | cp[0]);
1826 	FILTER_EMIT(RFCR_RFADDR_NODE2, (cp[3] << 8) | cp[2]);
1827 	FILTER_EMIT(RFCR_RFADDR_NODE4, (cp[5] << 8) | cp[4]);
1828 
1829 	if ((ifp->if_flags & IFF_ALLMULTI) == 0) {
1830 		/*
1831 		 * Program the multicast hash table.
1832 		 */
1833 		FILTER_EMIT(RFCR_RFADDR_MC0, mchash[0]);
1834 		FILTER_EMIT(RFCR_RFADDR_MC1, mchash[1]);
1835 		FILTER_EMIT(RFCR_RFADDR_MC2, mchash[2]);
1836 		FILTER_EMIT(RFCR_RFADDR_MC3, mchash[3]);
1837 		FILTER_EMIT(RFCR_RFADDR_MC4, mchash[4]);
1838 		FILTER_EMIT(RFCR_RFADDR_MC5, mchash[5]);
1839 		FILTER_EMIT(RFCR_RFADDR_MC6, mchash[6]);
1840 		FILTER_EMIT(RFCR_RFADDR_MC7, mchash[7]);
1841 	}
1842 #undef FILTER_EMIT
1843 
1844 	/*
1845 	 * Re-enable the receiver filter.
1846 	 */
1847 	bus_space_write_4(st, sh, SIP_RFCR, sc->sc_rfcr);
1848 }
1849 
1850 /*
1851  * sip_mii_readreg:	[mii interface function]
1852  *
1853  *	Read a PHY register on the MII.
1854  */
1855 int
1856 sip_mii_readreg(self, phy, reg)
1857 	struct device *self;
1858 	int phy, reg;
1859 {
1860 	struct sip_softc *sc = (struct sip_softc *) self;
1861 	u_int32_t enphy;
1862 
1863 	/*
1864 	 * The SiS 900 has only an internal PHY on the MII.  Only allow
1865 	 * MII address 0.
1866 	 */
1867 	if (phy != 0)
1868 		return (0);
1869 
1870 	bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_ENPHY,
1871 	    (reg << ENPHY_REGADDR_SHIFT) | ENPHY_RWCMD | ENPHY_ACCESS);
1872 	do {
1873 		enphy = bus_space_read_4(sc->sc_st, sc->sc_sh, SIP_ENPHY);
1874 	} while (enphy & ENPHY_ACCESS);
1875 	return ((enphy & ENPHY_PHYDATA) >> ENPHY_DATA_SHIFT);
1876 }
1877 
1878 /*
1879  * sip_mii_writereg:	[mii interface function]
1880  *
1881  *	Write a PHY register on the MII.
1882  */
1883 void
1884 sip_mii_writereg(self, phy, reg, val)
1885 	struct device *self;
1886 	int phy, reg, val;
1887 {
1888 	struct sip_softc *sc = (struct sip_softc *) self;
1889 	u_int32_t enphy;
1890 
1891 	/*
1892 	 * The SiS 900 has only an internal PHY on the MII.  Only allow
1893 	 * MII address 0.
1894 	 */
1895 	if (phy != 0)
1896 		return;
1897 
1898 	bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_ENPHY,
1899 	    (val << ENPHY_DATA_SHIFT) | (reg << ENPHY_REGADDR_SHIFT) |
1900 	    ENPHY_ACCESS);
1901 	do {
1902 		enphy = bus_space_read_4(sc->sc_st, sc->sc_sh, SIP_ENPHY);
1903 	} while (enphy & ENPHY_ACCESS);
1904 }
1905 
1906 /*
1907  * sip_mii_statchg:	[mii interface function]
1908  *
1909  *	Callback from MII layer when media changes.
1910  */
1911 void
1912 sip_mii_statchg(self)
1913 	struct device *self;
1914 {
1915 	struct sip_softc *sc = (struct sip_softc *) self;
1916 	u_int32_t flowctl;
1917 
1918 	/*
1919 	 * Update TXCFG for full-duplex operation.
1920 	 */
1921 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0)
1922 		sc->sc_txcfg |= (TXCFG_CSI | TXCFG_HBI);
1923 	else
1924 		sc->sc_txcfg &= ~(TXCFG_CSI | TXCFG_HBI);
1925 
1926 	/*
1927 	 * Update RXCFG for full-duplex or loopback.
1928 	 */
1929 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0 ||
1930 	    IFM_SUBTYPE(sc->sc_mii.mii_media_active) == IFM_LOOP)
1931 		sc->sc_rxcfg |= RXCFG_ATX;
1932 	else
1933 		sc->sc_rxcfg &= ~RXCFG_ATX;
1934 
1935 	/*
1936 	 * Update IMR for use of 802.3x flow control.
1937 	 */
1938 	if ((sc->sc_mii.mii_media_active & IFM_FLOW) != 0) {
1939 		sc->sc_imr |= (ISR_PAUSE_END|ISR_PAUSE_ST);
1940 		flowctl = FLOWCTL_FLOWEN;
1941 	} else {
1942 		sc->sc_imr &= ~(ISR_PAUSE_END|ISR_PAUSE_ST);
1943 		flowctl = 0;
1944 	}
1945 
1946 	bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_TXCFG, sc->sc_txcfg);
1947 	bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_RXCFG, sc->sc_rxcfg);
1948 	bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_IMR, sc->sc_imr);
1949 	bus_space_write_4(sc->sc_st, sc->sc_sh, SIP_FLOWCTL, flowctl);
1950 
1951 	/* XXX Update ifp->if_baudrate */
1952 }
1953 
1954 /*
1955  * sip_mediastatus:	[ifmedia interface function]
1956  *
1957  *	Get the current interface media status.
1958  */
1959 void
1960 sip_mediastatus(ifp, ifmr)
1961 	struct ifnet *ifp;
1962 	struct ifmediareq *ifmr;
1963 {
1964 	struct sip_softc *sc = ifp->if_softc;
1965 
1966 	mii_pollstat(&sc->sc_mii);
1967 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
1968 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
1969 }
1970 
1971 /*
1972  * sip_mediachange:	[ifmedia interface function]
1973  *
1974  *	Set hardware to newly-selected media.
1975  */
1976 int
1977 sip_mediachange(ifp)
1978 	struct ifnet *ifp;
1979 {
1980 	struct sip_softc *sc = ifp->if_softc;
1981 
1982 	if (ifp->if_flags & IFF_UP)
1983 		mii_mediachg(&sc->sc_mii);
1984 	return (0);
1985 }
1986