xref: /openbsd/sys/dev/pci/if_pcn.c (revision fc61954a)
1 /*	$OpenBSD: if_pcn.c,v 1.41 2016/04/13 10:34:32 mpi Exp $	*/
2 /*	$NetBSD: if_pcn.c,v 1.26 2005/05/07 09:15:44 is Exp $	*/
3 
4 /*
5  * Copyright (c) 2001 Wasabi Systems, Inc.
6  * All rights reserved.
7  *
8  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed for the NetBSD Project by
21  *	Wasabi Systems, Inc.
22  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
23  *    or promote products derived from this software without specific prior
24  *    written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Device driver for the AMD PCnet-PCI series of Ethernet
41  * chips:
42  *
43  *	* Am79c970 PCnet-PCI Single-Chip Ethernet Controller for PCI
44  *	  Local Bus
45  *
46  *	* Am79c970A PCnet-PCI II Single-Chip Full-Duplex Ethernet Controller
47  *	  for PCI Local Bus
48  *
49  *	* Am79c971 PCnet-FAST Single-Chip Full-Duplex 10/100Mbps
50  *	  Ethernet Controller for PCI Local Bus
51  *
52  *	* Am79c972 PCnet-FAST+ Enhanced 10/100Mbps PCI Ethernet Controller
53  *	  with OnNow Support
54  *
55  *	* Am79c973/Am79c975 PCnet-FAST III Single-Chip 10/100Mbps PCI
56  *	  Ethernet Controller with Integrated PHY
57  *
58  * This also supports the virtual PCnet-PCI Ethernet interface found
59  * in VMware.
60  *
61  * TODO:
62  *
63  *	* Split this into bus-specific and bus-independent portions.
64  *	  The core could also be used for the ILACC (Am79900) 32-bit
65  *	  Ethernet chip (XXX only if we use an ILACC-compatible SWSTYLE).
66  */
67 
68 #include "bpfilter.h"
69 
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/timeout.h>
73 #include <sys/mbuf.h>
74 #include <sys/malloc.h>
75 #include <sys/kernel.h>
76 #include <sys/socket.h>
77 #include <sys/ioctl.h>
78 #include <sys/errno.h>
79 #include <sys/device.h>
80 #include <sys/queue.h>
81 #include <sys/endian.h>
82 
83 #include <net/if.h>
84 #include <net/if_dl.h>
85 
86 #include <netinet/in.h>
87 #include <netinet/if_ether.h>
88 
89 #include <net/if_media.h>
90 
91 #if NBPFILTER > 0
92 #include <net/bpf.h>
93 #endif
94 
95 #include <machine/bus.h>
96 #include <machine/intr.h>
97 
98 #include <dev/mii/miivar.h>
99 
100 #include <dev/ic/am79900reg.h>
101 #include <dev/ic/lancereg.h>
102 
103 #include <dev/pci/pcireg.h>
104 #include <dev/pci/pcivar.h>
105 #include <dev/pci/pcidevs.h>
106 
107 /*
108  * Register definitions for the AMD PCnet-PCI series of Ethernet
109  * chips.
110  *
111  * These are only the registers that we access directly from PCI
112  * space.  Everything else (accessed via the RAP + RDP/BDP) is
113  * defined in <dev/ic/lancereg.h>.
114  */
115 
116 /*
117  * PCI configuration space.
118  */
119 
120 #define	PCN_PCI_CBIO	(PCI_MAPREG_START + 0x00)
121 #define	PCN_PCI_CBMEM	(PCI_MAPREG_START + 0x04)
122 
123 /*
124  * I/O map in Word I/O mode.
125  */
126 
127 #define	PCN16_APROM	0x00
128 #define	PCN16_RDP	0x10
129 #define	PCN16_RAP	0x12
130 #define	PCN16_RESET	0x14
131 #define	PCN16_BDP	0x16
132 
133 /*
134  * I/O map in DWord I/O mode.
135  */
136 
137 #define	PCN32_APROM	0x00
138 #define	PCN32_RDP	0x10
139 #define	PCN32_RAP	0x14
140 #define	PCN32_RESET	0x18
141 #define	PCN32_BDP	0x1c
142 
143 /*
144  * Transmit descriptor list size.  This is arbitrary, but allocate
145  * enough descriptors for 128 pending transmissions, and 4 segments
146  * per packet.  This MUST work out to a power of 2.
147  *
148  * NOTE: We can't have any more than 512 Tx descriptors, SO BE CAREFUL!
149  *
150  * So we play a little trick here.  We give each packet up to 16
151  * DMA segments, but only allocate the max of 512 descriptors.  The
152  * transmit logic can deal with this, we just are hoping to sneak by.
153  */
154 #define	PCN_NTXSEGS		16
155 
156 #define	PCN_TXQUEUELEN		128
157 #define	PCN_TXQUEUELEN_MASK	(PCN_TXQUEUELEN - 1)
158 #define	PCN_NTXDESC		512
159 #define	PCN_NTXDESC_MASK	(PCN_NTXDESC - 1)
160 #define	PCN_NEXTTX(x)		(((x) + 1) & PCN_NTXDESC_MASK)
161 #define	PCN_NEXTTXS(x)		(((x) + 1) & PCN_TXQUEUELEN_MASK)
162 
163 /* Tx interrupt every N + 1 packets. */
164 #define	PCN_TXINTR_MASK		7
165 
166 /*
167  * Receive descriptor list size.  We have one Rx buffer per incoming
168  * packet, so this logic is a little simpler.
169  */
170 #define	PCN_NRXDESC		128
171 #define	PCN_NRXDESC_MASK	(PCN_NRXDESC - 1)
172 #define	PCN_NEXTRX(x)		(((x) + 1) & PCN_NRXDESC_MASK)
173 
174 /*
175  * Control structures are DMA'd to the PCnet chip.  We allocate them in
176  * a single clump that maps to a single DMA segment to make several things
177  * easier.
178  */
179 struct pcn_control_data {
180 	/* The transmit descriptors. */
181 	struct letmd pcd_txdescs[PCN_NTXDESC];
182 
183 	/* The receive descriptors. */
184 	struct lermd pcd_rxdescs[PCN_NRXDESC];
185 
186 	/* The init block. */
187 	struct leinit pcd_initblock;
188 };
189 
190 #define	PCN_CDOFF(x)	offsetof(struct pcn_control_data, x)
191 #define	PCN_CDTXOFF(x)	PCN_CDOFF(pcd_txdescs[(x)])
192 #define	PCN_CDRXOFF(x)	PCN_CDOFF(pcd_rxdescs[(x)])
193 #define	PCN_CDINITOFF	PCN_CDOFF(pcd_initblock)
194 
195 /*
196  * Software state for transmit jobs.
197  */
198 struct pcn_txsoft {
199 	struct mbuf *txs_mbuf;		/* head of our mbuf chain */
200 	bus_dmamap_t txs_dmamap;	/* our DMA map */
201 	int txs_firstdesc;		/* first descriptor in packet */
202 	int txs_lastdesc;		/* last descriptor in packet */
203 };
204 
205 /*
206  * Software state for receive jobs.
207  */
208 struct pcn_rxsoft {
209 	struct mbuf *rxs_mbuf;		/* head of our mbuf chain */
210 	bus_dmamap_t rxs_dmamap;	/* our DMA map */
211 };
212 
213 /*
214  * Description of Rx FIFO watermarks for various revisions.
215  */
216 static const char * const pcn_79c970_rcvfw[] = {
217 	"16 bytes",
218 	"64 bytes",
219 	"128 bytes",
220 	NULL,
221 };
222 
223 static const char * const pcn_79c971_rcvfw[] = {
224 	"16 bytes",
225 	"64 bytes",
226 	"112 bytes",
227 	NULL,
228 };
229 
230 /*
231  * Description of Tx start points for various revisions.
232  */
233 static const char * const pcn_79c970_xmtsp[] = {
234 	"8 bytes",
235 	"64 bytes",
236 	"128 bytes",
237 	"248 bytes",
238 };
239 
240 static const char * const pcn_79c971_xmtsp[] = {
241 	"20 bytes",
242 	"64 bytes",
243 	"128 bytes",
244 	"248 bytes",
245 };
246 
247 static const char * const pcn_79c971_xmtsp_sram[] = {
248 	"44 bytes",
249 	"64 bytes",
250 	"128 bytes",
251 	"store-and-forward",
252 };
253 
254 /*
255  * Description of Tx FIFO watermarks for various revisions.
256  */
257 static const char * const pcn_79c970_xmtfw[] = {
258 	"16 bytes",
259 	"64 bytes",
260 	"128 bytes",
261 	NULL,
262 };
263 
264 static const char * const pcn_79c971_xmtfw[] = {
265 	"16 bytes",
266 	"64 bytes",
267 	"108 bytes",
268 	NULL,
269 };
270 
271 /*
272  * Software state per device.
273  */
274 struct pcn_softc {
275 	struct device sc_dev;		/* generic device information */
276 	bus_space_tag_t sc_st;		/* bus space tag */
277 	bus_space_handle_t sc_sh;	/* bus space handle */
278 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
279 	struct arpcom sc_arpcom;	/* Ethernet common data */
280 
281 	/* Points to our media routines, etc. */
282 	const struct pcn_variant *sc_variant;
283 
284 	void *sc_ih;			/* interrupt cookie */
285 
286 	struct mii_data sc_mii;		/* MII/media information */
287 
288 	struct timeout sc_tick_timeout;	/* tick timeout */
289 
290 	bus_dmamap_t sc_cddmamap;	/* control data DMA map */
291 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
292 
293 	/* Software state for transmit and receive descriptors. */
294 	struct pcn_txsoft sc_txsoft[PCN_TXQUEUELEN];
295 	struct pcn_rxsoft sc_rxsoft[PCN_NRXDESC];
296 
297 	/* Control data structures */
298 	struct pcn_control_data *sc_control_data;
299 #define	sc_txdescs	sc_control_data->pcd_txdescs
300 #define	sc_rxdescs	sc_control_data->pcd_rxdescs
301 #define	sc_initblock	sc_control_data->pcd_initblock
302 
303 	const char * const *sc_rcvfw_desc;	/* Rx FIFO watermark info */
304 	int sc_rcvfw;
305 
306 	const char * const *sc_xmtsp_desc;	/* Tx start point info */
307 	int sc_xmtsp;
308 
309 	const char * const *sc_xmtfw_desc;	/* Tx FIFO watermark info */
310 	int sc_xmtfw;
311 
312 	int sc_flags;			/* misc. flags; see below */
313 	int sc_swstyle;			/* the software style in use */
314 
315 	int sc_txfree;			/* number of free Tx descriptors */
316 	int sc_txnext;			/* next ready Tx descriptor */
317 
318 	int sc_txsfree;			/* number of free Tx jobs */
319 	int sc_txsnext;			/* next free Tx job */
320 	int sc_txsdirty;		/* dirty Tx jobs */
321 
322 	int sc_rxptr;			/* next ready Rx descriptor/job */
323 
324 	uint32_t sc_csr5;		/* prototype CSR5 register */
325 	uint32_t sc_mode;		/* prototype MODE register */
326 };
327 
328 /* sc_flags */
329 #define	PCN_F_HAS_MII		0x0001	/* has MII */
330 
331 #define	PCN_CDTXADDR(sc, x)	((sc)->sc_cddma + PCN_CDTXOFF((x)))
332 #define	PCN_CDRXADDR(sc, x)	((sc)->sc_cddma + PCN_CDRXOFF((x)))
333 #define	PCN_CDINITADDR(sc)	((sc)->sc_cddma + PCN_CDINITOFF)
334 
335 #define	PCN_CDTXSYNC(sc, x, n, ops)					\
336 do {									\
337 	int __x, __n;							\
338 									\
339 	__x = (x);							\
340 	__n = (n);							\
341 									\
342 	/* If it will wrap around, sync to the end of the ring. */	\
343 	if ((__x + __n) > PCN_NTXDESC) {				\
344 		bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,	\
345 		    PCN_CDTXOFF(__x), sizeof(struct letmd) *		\
346 		    (PCN_NTXDESC - __x), (ops));			\
347 		__n -= (PCN_NTXDESC - __x);				\
348 		__x = 0;						\
349 	}								\
350 									\
351 	/* Now sync whatever is left. */				\
352 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
353 	    PCN_CDTXOFF(__x), sizeof(struct letmd) * __n, (ops));	\
354 } while (/*CONSTCOND*/0)
355 
356 #define	PCN_CDRXSYNC(sc, x, ops)					\
357 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
358 	    PCN_CDRXOFF((x)), sizeof(struct lermd), (ops))
359 
360 #define	PCN_CDINITSYNC(sc, ops)						\
361 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
362 	    PCN_CDINITOFF, sizeof(struct leinit), (ops))
363 
364 #define	PCN_INIT_RXDESC(sc, x)						\
365 do {									\
366 	struct pcn_rxsoft *__rxs = &(sc)->sc_rxsoft[(x)];		\
367 	struct lermd *__rmd = &(sc)->sc_rxdescs[(x)];			\
368 	struct mbuf *__m = __rxs->rxs_mbuf;				\
369 									\
370 	/*								\
371 	 * Note: We scoot the packet forward 2 bytes in the buffer	\
372 	 * so that the payload after the Ethernet header is aligned	\
373 	 * to a 4-byte boundary.					\
374 	 */								\
375 	__m->m_data = __m->m_ext.ext_buf + 2;				\
376 									\
377 	if ((sc)->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3) {		\
378 		__rmd->rmd2 =						\
379 		    htole32(__rxs->rxs_dmamap->dm_segs[0].ds_addr + 2);	\
380 		__rmd->rmd0 = 0;					\
381 	} else {							\
382 		__rmd->rmd2 = 0;					\
383 		__rmd->rmd0 =						\
384 		    htole32(__rxs->rxs_dmamap->dm_segs[0].ds_addr + 2);	\
385 	}								\
386 	__rmd->rmd1 = htole32(LE_R1_OWN|LE_R1_ONES| 			\
387 	    (LE_BCNT(MCLBYTES - 2) & LE_R1_BCNT_MASK));			\
388 	PCN_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);\
389 } while(/*CONSTCOND*/0)
390 
391 void	pcn_start(struct ifnet *);
392 void	pcn_watchdog(struct ifnet *);
393 int	pcn_ioctl(struct ifnet *, u_long, caddr_t);
394 int	pcn_init(struct ifnet *);
395 void	pcn_stop(struct ifnet *, int);
396 
397 void	pcn_reset(struct pcn_softc *);
398 void	pcn_rxdrain(struct pcn_softc *);
399 int	pcn_add_rxbuf(struct pcn_softc *, int);
400 void	pcn_tick(void *);
401 
402 void	pcn_spnd(struct pcn_softc *);
403 
404 void	pcn_set_filter(struct pcn_softc *);
405 
406 int	pcn_intr(void *);
407 void	pcn_txintr(struct pcn_softc *);
408 int	pcn_rxintr(struct pcn_softc *);
409 
410 int	pcn_mii_readreg(struct device *, int, int);
411 void	pcn_mii_writereg(struct device *, int, int, int);
412 void	pcn_mii_statchg(struct device *);
413 
414 void	pcn_79c970_mediainit(struct pcn_softc *);
415 int	pcn_79c970_mediachange(struct ifnet *);
416 void	pcn_79c970_mediastatus(struct ifnet *, struct ifmediareq *);
417 
418 void	pcn_79c971_mediainit(struct pcn_softc *);
419 int	pcn_79c971_mediachange(struct ifnet *);
420 void	pcn_79c971_mediastatus(struct ifnet *, struct ifmediareq *);
421 
422 /*
423  * Description of a PCnet-PCI variant.  Used to select media access
424  * method, mostly, and to print a nice description of the chip.
425  */
426 static const struct pcn_variant {
427 	const char *pcv_desc;
428 	void (*pcv_mediainit)(struct pcn_softc *);
429 	uint16_t pcv_chipid;
430 } pcn_variants[] = {
431 	{ "Am79c970",
432 	  pcn_79c970_mediainit,
433 	  PARTID_Am79c970 },
434 
435 	{ "Am79c970A",
436 	  pcn_79c970_mediainit,
437 	  PARTID_Am79c970A },
438 
439 	{ "Am79c971",
440 	  pcn_79c971_mediainit,
441 	  PARTID_Am79c971 },
442 
443 	{ "Am79c972",
444 	  pcn_79c971_mediainit,
445 	  PARTID_Am79c972 },
446 
447 	{ "Am79c973",
448 	  pcn_79c971_mediainit,
449 	  PARTID_Am79c973 },
450 
451 	{ "Am79c975",
452 	  pcn_79c971_mediainit,
453 	  PARTID_Am79c975 },
454 
455 	{ "Am79c976",
456 	  pcn_79c971_mediainit,
457 	  PARTID_Am79c976 },
458 
459 	{ "Am79c978",
460 	  pcn_79c971_mediainit,
461 	  PARTID_Am79c978 },
462 
463 	{ "Unknown",
464 	  pcn_79c971_mediainit,
465 	  0 },
466 };
467 
468 int	pcn_copy_small = 0;
469 
470 int	pcn_match(struct device *, void *, void *);
471 void	pcn_attach(struct device *, struct device *, void *);
472 
473 struct cfattach pcn_ca = {
474 	sizeof(struct pcn_softc), pcn_match, pcn_attach,
475 };
476 
477 const struct pci_matchid pcn_devices[] = {
478 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_PCNET_PCI },
479 	{ PCI_VENDOR_AMD, PCI_PRODUCT_AMD_PCHOME_PCI }
480 };
481 
482 struct cfdriver pcn_cd = {
483 	NULL, "pcn", DV_IFNET
484 };
485 
486 /*
487  * Routines to read and write the PCnet-PCI CSR/BCR space.
488  */
489 
490 static __inline uint32_t
491 pcn_csr_read(struct pcn_softc *sc, int reg)
492 {
493 
494 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
495 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_RDP));
496 }
497 
498 static __inline void
499 pcn_csr_write(struct pcn_softc *sc, int reg, uint32_t val)
500 {
501 
502 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
503 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RDP, val);
504 }
505 
506 static __inline uint32_t
507 pcn_bcr_read(struct pcn_softc *sc, int reg)
508 {
509 
510 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
511 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_BDP));
512 }
513 
514 static __inline void
515 pcn_bcr_write(struct pcn_softc *sc, int reg, uint32_t val)
516 {
517 
518 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
519 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_BDP, val);
520 }
521 
522 static const struct pcn_variant *
523 pcn_lookup_variant(uint16_t chipid)
524 {
525 	const struct pcn_variant *pcv;
526 
527 	for (pcv = pcn_variants; pcv->pcv_chipid != 0; pcv++) {
528 		if (chipid == pcv->pcv_chipid)
529 			return (pcv);
530 	}
531 
532 	/*
533 	 * This covers unknown chips, which we simply treat like
534 	 * a generic PCnet-FAST.
535 	 */
536 	return (pcv);
537 }
538 
539 int
540 pcn_match(struct device *parent, void *match, void *aux)
541 {
542 	struct pci_attach_args *pa = aux;
543 
544 	/*
545 	 * IBM makes a PCI variant of this card which shows up as a
546 	 * Trident Microsystems 4DWAVE DX (ethernet network, revision 0x25)
547 	 * this card is truly a pcn card, so we have a special case match for
548 	 * it.
549 	 */
550 	if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_TRIDENT &&
551 	    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_TRIDENT_4DWAVE_DX &&
552 	    PCI_CLASS(pa->pa_class) == PCI_CLASS_NETWORK)
553 		return(1);
554 
555 	return (pci_matchbyid((struct pci_attach_args *)aux, pcn_devices,
556 	    nitems(pcn_devices)));
557 }
558 
559 void
560 pcn_attach(struct device *parent, struct device *self, void *aux)
561 {
562 	struct pcn_softc *sc = (struct pcn_softc *) self;
563 	struct pci_attach_args *pa = aux;
564 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
565 	pci_chipset_tag_t pc = pa->pa_pc;
566 	pci_intr_handle_t ih;
567 	const char *intrstr = NULL;
568 	bus_space_tag_t iot, memt;
569 	bus_space_handle_t ioh, memh;
570 	bus_dma_segment_t seg;
571 	int ioh_valid, memh_valid;
572 	int i, rseg, error;
573 	uint32_t chipid, reg;
574 	uint8_t enaddr[ETHER_ADDR_LEN];
575 
576 	timeout_set(&sc->sc_tick_timeout, pcn_tick, sc);
577 
578 	/*
579 	 * Map the device.
580 	 */
581 	ioh_valid = (pci_mapreg_map(pa, PCN_PCI_CBIO, PCI_MAPREG_TYPE_IO, 0,
582 	    &iot, &ioh, NULL, NULL, 0) == 0);
583 	memh_valid = (pci_mapreg_map(pa, PCN_PCI_CBMEM,
584 	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
585 	    &memt, &memh, NULL, NULL, 0) == 0);
586 
587 	if (memh_valid) {
588 		sc->sc_st = memt;
589 		sc->sc_sh = memh;
590 	} else if (ioh_valid) {
591 		sc->sc_st = iot;
592 		sc->sc_sh = ioh;
593 	} else {
594 		printf(": unable to map device registers\n");
595 		return;
596 	}
597 
598 	sc->sc_dmat = pa->pa_dmat;
599 
600 	/* Get it out of power save mode, if needed. */
601 	pci_set_powerstate(pc, pa->pa_tag, PCI_PMCSR_STATE_D0);
602 
603 	/*
604 	 * Reset the chip to a known state.  This also puts the
605 	 * chip into 32-bit mode.
606 	 */
607 	pcn_reset(sc);
608 
609 #if !defined(PCN_NO_PROM)
610 
611 	/*
612 	 * Read the Ethernet address from the EEPROM.
613 	 */
614 	for (i = 0; i < ETHER_ADDR_LEN; i++)
615 		enaddr[i] = bus_space_read_1(sc->sc_st, sc->sc_sh,
616 		    PCN32_APROM + i);
617 #else
618 	/*
619 	 * The PROM is not used; instead we assume that the MAC address
620 	 * has been programmed into the device's physical address
621 	 * registers by the boot firmware
622 	 */
623 
624         for (i=0; i < 3; i++) {
625 		uint32_t val;
626 		val = pcn_csr_read(sc, LE_CSR12 + i);
627 		enaddr[2*i] = val & 0x0ff;
628 		enaddr[2*i+1] = (val >> 8) & 0x0ff;
629 	}
630 #endif
631 
632 	/*
633 	 * Now that the device is mapped, attempt to figure out what
634 	 * kind of chip we have.  Note that IDL has all 32 bits of
635 	 * the chip ID when we're in 32-bit mode.
636 	 */
637 	chipid = pcn_csr_read(sc, LE_CSR88);
638 	sc->sc_variant = pcn_lookup_variant(CHIPID_PARTID(chipid));
639 
640 	/*
641 	 * Map and establish our interrupt.
642 	 */
643 	if (pci_intr_map(pa, &ih)) {
644 		printf(": unable to map interrupt\n");
645 		return;
646 	}
647 	intrstr = pci_intr_string(pc, ih);
648 	sc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, pcn_intr, sc,
649 	    self->dv_xname);
650 	if (sc->sc_ih == NULL) {
651 		printf(": unable to establish interrupt");
652 		if (intrstr != NULL)
653 			printf(" at %s", intrstr);
654 		printf("\n");
655 		return;
656 	}
657 
658 	/*
659 	 * Allocate the control data structures, and create and load the
660 	 * DMA map for it.
661 	 */
662 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
663 	     sizeof(struct pcn_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
664 	     0)) != 0) {
665 		printf(": unable to allocate control data, error = %d\n",
666 		    error);
667 		return;
668 	}
669 
670 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
671 	     sizeof(struct pcn_control_data), (caddr_t *)&sc->sc_control_data,
672 	     BUS_DMA_COHERENT)) != 0) {
673 		printf(": unable to map control data, error = %d\n",
674 		    error);
675 		goto fail_1;
676 	}
677 
678 	if ((error = bus_dmamap_create(sc->sc_dmat,
679 	     sizeof(struct pcn_control_data), 1,
680 	     sizeof(struct pcn_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
681 		printf(": unable to create control data DMA map, "
682 		    "error = %d\n", error);
683 		goto fail_2;
684 	}
685 
686 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
687 	     sc->sc_control_data, sizeof(struct pcn_control_data), NULL,
688 	     0)) != 0) {
689 		printf(": unable to load control data DMA map, error = %d\n",
690 		    error);
691 		goto fail_3;
692 	}
693 
694 	/* Create the transmit buffer DMA maps. */
695 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
696 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
697 		     PCN_NTXSEGS, MCLBYTES, 0, 0,
698 		     &sc->sc_txsoft[i].txs_dmamap)) != 0) {
699 			printf(": unable to create tx DMA map %d, "
700 			    "error = %d\n", i, error);
701 			goto fail_4;
702 		}
703 	}
704 
705 	/* Create the receive buffer DMA maps. */
706 	for (i = 0; i < PCN_NRXDESC; i++) {
707 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
708 		     MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
709 			printf(": unable to create rx DMA map %d, "
710 			    "error = %d\n", i, error);
711 			goto fail_5;
712 		}
713 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
714 	}
715 
716 	printf(", %s, rev %d: %s, address %s\n", sc->sc_variant->pcv_desc,
717 	    CHIPID_VER(chipid), intrstr, ether_sprintf(enaddr));
718 
719 	/* Initialize our media structures. */
720 	(*sc->sc_variant->pcv_mediainit)(sc);
721 
722 	/*
723 	 * Initialize FIFO watermark info.
724 	 */
725 	switch (sc->sc_variant->pcv_chipid) {
726 	case PARTID_Am79c970:
727 	case PARTID_Am79c970A:
728 		sc->sc_rcvfw_desc = pcn_79c970_rcvfw;
729 		sc->sc_xmtsp_desc = pcn_79c970_xmtsp;
730 		sc->sc_xmtfw_desc = pcn_79c970_xmtfw;
731 		break;
732 
733 	default:
734 		sc->sc_rcvfw_desc = pcn_79c971_rcvfw;
735 		/*
736 		 * Read BCR25 to determine how much SRAM is
737 		 * on the board.  If > 0, then we the chip
738 		 * uses different Start Point thresholds.
739 		 *
740 		 * Note BCR25 and BCR26 are loaded from the
741 		 * EEPROM on RST, and unaffected by S_RESET,
742 		 * so we don't really have to worry about
743 		 * them except for this.
744 		 */
745 		reg = pcn_bcr_read(sc, LE_BCR25) & 0x00ff;
746 		if (reg != 0)
747 			sc->sc_xmtsp_desc = pcn_79c971_xmtsp_sram;
748 		else
749 			sc->sc_xmtsp_desc = pcn_79c971_xmtsp;
750 		sc->sc_xmtfw_desc = pcn_79c971_xmtfw;
751 		break;
752 	}
753 
754 	/*
755 	 * Set up defaults -- see the tables above for what these
756 	 * values mean.
757 	 *
758 	 * XXX How should we tune RCVFW and XMTFW?
759 	 */
760 	sc->sc_rcvfw = 1;	/* minimum for full-duplex */
761 	sc->sc_xmtsp = 1;
762 	sc->sc_xmtfw = 0;
763 
764 	ifp = &sc->sc_arpcom.ac_if;
765 	bcopy(enaddr, sc->sc_arpcom.ac_enaddr, ETHER_ADDR_LEN);
766 	bcopy(sc->sc_dev.dv_xname, ifp->if_xname, IFNAMSIZ);
767 	ifp->if_softc = sc;
768 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
769 	ifp->if_ioctl = pcn_ioctl;
770 	ifp->if_start = pcn_start;
771 	ifp->if_watchdog = pcn_watchdog;
772 	IFQ_SET_MAXLEN(&ifp->if_snd, PCN_NTXDESC -1);
773 
774 	/* Attach the interface. */
775 	if_attach(ifp);
776 	ether_ifattach(ifp);
777 	return;
778 
779 	/*
780 	 * Free any resources we've allocated during the failed attach
781 	 * attempt.  Do this in reverse order and fall through.
782 	 */
783  fail_5:
784 	for (i = 0; i < PCN_NRXDESC; i++) {
785 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
786 			bus_dmamap_destroy(sc->sc_dmat,
787 			    sc->sc_rxsoft[i].rxs_dmamap);
788 	}
789  fail_4:
790 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
791 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
792 			bus_dmamap_destroy(sc->sc_dmat,
793 			    sc->sc_txsoft[i].txs_dmamap);
794 	}
795 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
796  fail_3:
797 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
798  fail_2:
799 	bus_dmamem_unmap(sc->sc_dmat, (caddr_t)sc->sc_control_data,
800 	    sizeof(struct pcn_control_data));
801  fail_1:
802 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
803 }
804 
805 /*
806  * pcn_start:		[ifnet interface function]
807  *
808  *	Start packet transmission on the interface.
809  */
810 void
811 pcn_start(struct ifnet *ifp)
812 {
813 	struct pcn_softc *sc = ifp->if_softc;
814 	struct mbuf *m0, *m;
815 	struct pcn_txsoft *txs;
816 	bus_dmamap_t dmamap;
817 	int error, nexttx, lasttx = -1, ofree, seg;
818 
819 	if (!(ifp->if_flags & IFF_RUNNING) || ifq_is_oactive(&ifp->if_snd))
820 		return;
821 
822 	/*
823 	 * Remember the previous number of free descriptors and
824 	 * the first descriptor we'll use.
825 	 */
826 	ofree = sc->sc_txfree;
827 
828 	/*
829 	 * Loop through the send queue, setting up transmit descriptors
830 	 * until we drain the queue, or use up all available transmit
831 	 * descriptors.
832 	 */
833 	for (;;) {
834 		/* Grab a packet off the queue. */
835 		m0 = ifq_deq_begin(&ifp->if_snd);
836 		if (m0 == NULL)
837 			break;
838 		m = NULL;
839 
840 		/* Get a work queue entry. */
841 		if (sc->sc_txsfree == 0) {
842 			ifq_deq_rollback(&ifp->if_snd, m0);
843 			break;
844 		}
845 
846 		txs = &sc->sc_txsoft[sc->sc_txsnext];
847 		dmamap = txs->txs_dmamap;
848 
849 		/*
850 		 * Load the DMA map.  If this fails, the packet either
851 		 * didn't fit in the alloted number of segments, or we
852 		 * were short on resources.  In this case, we'll copy
853 		 * and try again.
854 		 */
855 		if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
856 		    BUS_DMA_WRITE|BUS_DMA_NOWAIT) != 0) {
857 			MGETHDR(m, M_DONTWAIT, MT_DATA);
858 			if (m == NULL) {
859 				ifq_deq_rollback(&ifp->if_snd, m0);
860 				break;
861 			}
862 			if (m0->m_pkthdr.len > MHLEN) {
863 				MCLGET(m, M_DONTWAIT);
864 				if ((m->m_flags & M_EXT) == 0) {
865 					ifq_deq_rollback(&ifp->if_snd, m0);
866 					m_freem(m);
867 					break;
868 				}
869 			}
870 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, caddr_t));
871 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
872 			error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
873 			    m, BUS_DMA_WRITE|BUS_DMA_NOWAIT);
874 			if (error) {
875 				ifq_deq_rollback(&ifp->if_snd, m0);
876 				break;
877 			}
878 		}
879 
880 		/*
881 		 * Ensure we have enough descriptors free to describe
882 		 * the packet.  Note, we always reserve one descriptor
883 		 * at the end of the ring as a termination point, to
884 		 * prevent wrap-around.
885 		 */
886 		if (dmamap->dm_nsegs > (sc->sc_txfree - 1)) {
887 			/*
888 			 * Not enough free descriptors to transmit this
889 			 * packet.  We haven't committed anything yet,
890 			 * so just unload the DMA map, put the packet
891 			 * back on the queue, and punt.  Notify the upper
892 			 * layer that there are not more slots left.
893 			 *
894 			 * XXX We could allocate an mbuf and copy, but
895 			 * XXX is it worth it?
896 			 */
897 			ifq_set_oactive(&ifp->if_snd);
898 			bus_dmamap_unload(sc->sc_dmat, dmamap);
899 			if (m != NULL)
900 				m_freem(m);
901 			ifq_deq_rollback(&ifp->if_snd, m0);
902 			break;
903 		}
904 
905 		ifq_deq_commit(&ifp->if_snd, m0);
906 		if (m != NULL) {
907 			m_freem(m0);
908 			m0 = m;
909 		}
910 
911 		/*
912 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
913 		 */
914 
915 		/* Sync the DMA map. */
916 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
917 		    BUS_DMASYNC_PREWRITE);
918 
919 		/*
920 		 * Initialize the transmit descriptors.
921 		 */
922 		if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3) {
923 			for (nexttx = sc->sc_txnext, seg = 0;
924 			     seg < dmamap->dm_nsegs;
925 			     seg++, nexttx = PCN_NEXTTX(nexttx)) {
926 				/*
927 				 * If this is the first descriptor we're
928 				 * enqueueing, don't set the OWN bit just
929 				 * yet.  That could cause a race condition.
930 				 * We'll do it below.
931 				 */
932 				sc->sc_txdescs[nexttx].tmd0 = 0;
933 				sc->sc_txdescs[nexttx].tmd2 =
934 				    htole32(dmamap->dm_segs[seg].ds_addr);
935 				sc->sc_txdescs[nexttx].tmd1 =
936 				    htole32(LE_T1_ONES |
937 				    (nexttx == sc->sc_txnext ? 0 : LE_T1_OWN) |
938 				    (LE_BCNT(dmamap->dm_segs[seg].ds_len) &
939 				     LE_T1_BCNT_MASK));
940 				lasttx = nexttx;
941 			}
942 		} else {
943 			for (nexttx = sc->sc_txnext, seg = 0;
944 			     seg < dmamap->dm_nsegs;
945 			     seg++, nexttx = PCN_NEXTTX(nexttx)) {
946 				/*
947 				 * If this is the first descriptor we're
948 				 * enqueueing, don't set the OWN bit just
949 				 * yet.  That could cause a race condition.
950 				 * We'll do it below.
951 				 */
952 				sc->sc_txdescs[nexttx].tmd0 =
953 				    htole32(dmamap->dm_segs[seg].ds_addr);
954 				sc->sc_txdescs[nexttx].tmd2 = 0;
955 				sc->sc_txdescs[nexttx].tmd1 =
956 				    htole32(LE_T1_ONES |
957 				    (nexttx == sc->sc_txnext ? 0 : LE_T1_OWN) |
958 				    (LE_BCNT(dmamap->dm_segs[seg].ds_len) &
959 				     LE_T1_BCNT_MASK));
960 				lasttx = nexttx;
961 			}
962 		}
963 
964 		KASSERT(lasttx != -1);
965 		/* Interrupt on the packet, if appropriate. */
966 		if ((sc->sc_txsnext & PCN_TXINTR_MASK) == 0)
967 			sc->sc_txdescs[lasttx].tmd1 |= htole32(LE_T1_LTINT);
968 
969 		/* Set `start of packet' and `end of packet' appropriately. */
970 		sc->sc_txdescs[lasttx].tmd1 |= htole32(LE_T1_ENP);
971 		sc->sc_txdescs[sc->sc_txnext].tmd1 |=
972 		    htole32(LE_T1_OWN|LE_T1_STP);
973 
974 		/* Sync the descriptors we're using. */
975 		PCN_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
976 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
977 
978 		/* Kick the transmitter. */
979 		pcn_csr_write(sc, LE_CSR0, LE_C0_INEA|LE_C0_TDMD);
980 
981 		/*
982 		 * Store a pointer to the packet so we can free it later,
983 		 * and remember what txdirty will be once the packet is
984 		 * done.
985 		 */
986 		txs->txs_mbuf = m0;
987 		txs->txs_firstdesc = sc->sc_txnext;
988 		txs->txs_lastdesc = lasttx;
989 
990 		/* Advance the tx pointer. */
991 		sc->sc_txfree -= dmamap->dm_nsegs;
992 		sc->sc_txnext = nexttx;
993 
994 		sc->sc_txsfree--;
995 		sc->sc_txsnext = PCN_NEXTTXS(sc->sc_txsnext);
996 
997 #if NBPFILTER > 0
998 		/* Pass the packet to any BPF listeners. */
999 		if (ifp->if_bpf)
1000 			bpf_mtap(ifp->if_bpf, m0, BPF_DIRECTION_OUT);
1001 #endif /* NBPFILTER > 0 */
1002 	}
1003 
1004 	if (sc->sc_txsfree == 0 || sc->sc_txfree == 0) {
1005 		/* No more slots left; notify upper layer. */
1006 		ifq_set_oactive(&ifp->if_snd);
1007 	}
1008 
1009 	if (sc->sc_txfree != ofree) {
1010 		/* Set a watchdog timer in case the chip flakes out. */
1011 		ifp->if_timer = 5;
1012 	}
1013 }
1014 
1015 /*
1016  * pcn_watchdog:	[ifnet interface function]
1017  *
1018  *	Watchdog timer handler.
1019  */
1020 void
1021 pcn_watchdog(struct ifnet *ifp)
1022 {
1023 	struct pcn_softc *sc = ifp->if_softc;
1024 
1025 	/*
1026 	 * Since we're not interrupting every packet, sweep
1027 	 * up before we report an error.
1028 	 */
1029 	pcn_txintr(sc);
1030 
1031 	if (sc->sc_txfree != PCN_NTXDESC) {
1032 		printf("%s: device timeout (txfree %d txsfree %d)\n",
1033 		    sc->sc_dev.dv_xname, sc->sc_txfree, sc->sc_txsfree);
1034 		ifp->if_oerrors++;
1035 
1036 		/* Reset the interface. */
1037 		(void) pcn_init(ifp);
1038 	}
1039 
1040 	/* Try to get more packets going. */
1041 	pcn_start(ifp);
1042 }
1043 
1044 /*
1045  * pcn_ioctl:		[ifnet interface function]
1046  *
1047  *	Handle control requests from the operator.
1048  */
1049 int
1050 pcn_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
1051 {
1052 	struct pcn_softc *sc = ifp->if_softc;
1053 	struct ifreq *ifr = (struct ifreq *) data;
1054 	int s, error = 0;
1055 
1056 	s = splnet();
1057 
1058 	switch (cmd) {
1059 	case SIOCSIFADDR:
1060 		ifp->if_flags |= IFF_UP;
1061 		if (!(ifp->if_flags & IFF_RUNNING))
1062 			pcn_init(ifp);
1063 		break;
1064 
1065 	case SIOCSIFFLAGS:
1066 		if (ifp->if_flags & IFF_UP) {
1067 			if (ifp->if_flags & IFF_RUNNING)
1068 				error = ENETRESET;
1069 			else
1070 				pcn_init(ifp);
1071 		} else {
1072 			if (ifp->if_flags & IFF_RUNNING)
1073 				pcn_stop(ifp, 1);
1074 		}
1075 		break;
1076 
1077 	case SIOCSIFMEDIA:
1078 	case SIOCGIFMEDIA:
1079 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
1080 		break;
1081 
1082 	default:
1083 		error = ether_ioctl(ifp, &sc->sc_arpcom, cmd, data);
1084 	}
1085 
1086 	if (error == ENETRESET) {
1087 		if (ifp->if_flags & IFF_RUNNING)
1088 			error = pcn_init(ifp);
1089 		else
1090 			error = 0;
1091 	}
1092 
1093 	splx(s);
1094 	return (error);
1095 }
1096 
1097 /*
1098  * pcn_intr:
1099  *
1100  *	Interrupt service routine.
1101  */
1102 int
1103 pcn_intr(void *arg)
1104 {
1105 	struct pcn_softc *sc = arg;
1106 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1107 	uint32_t csr0;
1108 	int wantinit, handled = 0;
1109 
1110 	for (wantinit = 0; wantinit == 0;) {
1111 		csr0 = pcn_csr_read(sc, LE_CSR0);
1112 		if ((csr0 & LE_C0_INTR) == 0)
1113 			break;
1114 
1115 		/* ACK the bits and re-enable interrupts. */
1116 		pcn_csr_write(sc, LE_CSR0, csr0 &
1117 		    (LE_C0_INEA|LE_C0_BABL|LE_C0_MISS|LE_C0_MERR|LE_C0_RINT|
1118 		     LE_C0_TINT|LE_C0_IDON));
1119 
1120 		handled = 1;
1121 
1122 		if (csr0 & LE_C0_RINT)
1123 			wantinit = pcn_rxintr(sc);
1124 
1125 		if (csr0 & LE_C0_TINT)
1126 			pcn_txintr(sc);
1127 
1128 		if (csr0 & LE_C0_ERR) {
1129 			if (csr0 & LE_C0_BABL)
1130 				ifp->if_oerrors++;
1131 			if (csr0 & LE_C0_MISS)
1132 				ifp->if_ierrors++;
1133 			if (csr0 & LE_C0_MERR) {
1134 				printf("%s: memory error\n",
1135 				    sc->sc_dev.dv_xname);
1136 				wantinit = 1;
1137 				break;
1138 			}
1139 		}
1140 
1141 		if ((csr0 & LE_C0_RXON) == 0) {
1142 			printf("%s: receiver disabled\n",
1143 			    sc->sc_dev.dv_xname);
1144 			ifp->if_ierrors++;
1145 			wantinit = 1;
1146 		}
1147 
1148 		if ((csr0 & LE_C0_TXON) == 0) {
1149 			printf("%s: transmitter disabled\n",
1150 			    sc->sc_dev.dv_xname);
1151 			ifp->if_oerrors++;
1152 			wantinit = 1;
1153 		}
1154 	}
1155 
1156 	if (handled) {
1157 		if (wantinit)
1158 			pcn_init(ifp);
1159 
1160 		/* Try to get more packets going. */
1161 		pcn_start(ifp);
1162 	}
1163 
1164 	return (handled);
1165 }
1166 
1167 /*
1168  * pcn_spnd:
1169  *
1170  *	Suspend the chip.
1171  */
1172 void
1173 pcn_spnd(struct pcn_softc *sc)
1174 {
1175 	int i;
1176 
1177 	pcn_csr_write(sc, LE_CSR5, sc->sc_csr5 | LE_C5_SPND);
1178 
1179 	for (i = 0; i < 10000; i++) {
1180 		if (pcn_csr_read(sc, LE_CSR5) & LE_C5_SPND)
1181 			return;
1182 		delay(5);
1183 	}
1184 
1185 	printf("%s: WARNING: chip failed to enter suspended state\n",
1186 	    sc->sc_dev.dv_xname);
1187 }
1188 
1189 /*
1190  * pcn_txintr:
1191  *
1192  *	Helper; handle transmit interrupts.
1193  */
1194 void
1195 pcn_txintr(struct pcn_softc *sc)
1196 {
1197 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1198 	struct pcn_txsoft *txs;
1199 	uint32_t tmd1, tmd2, tmd;
1200 	int i, j;
1201 
1202 	ifq_clr_oactive(&ifp->if_snd);
1203 
1204 	/*
1205 	 * Go through our Tx list and free mbufs for those
1206 	 * frames which have been transmitted.
1207 	 */
1208 	for (i = sc->sc_txsdirty; sc->sc_txsfree != PCN_TXQUEUELEN;
1209 	     i = PCN_NEXTTXS(i), sc->sc_txsfree++) {
1210 		txs = &sc->sc_txsoft[i];
1211 
1212 		PCN_CDTXSYNC(sc, txs->txs_firstdesc, txs->txs_dmamap->dm_nsegs,
1213 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1214 
1215 		tmd1 = letoh32(sc->sc_txdescs[txs->txs_lastdesc].tmd1);
1216 		if (tmd1 & LE_T1_OWN)
1217 			break;
1218 
1219 		/*
1220 		 * Slightly annoying -- we have to loop through the
1221 		 * descriptors we've used looking for ERR, since it
1222 		 * can appear on any descriptor in the chain.
1223 		 */
1224 		for (j = txs->txs_firstdesc;; j = PCN_NEXTTX(j)) {
1225 			tmd = letoh32(sc->sc_txdescs[j].tmd1);
1226 			if (tmd & LE_T1_ERR) {
1227 				ifp->if_oerrors++;
1228 				if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3)
1229 					tmd2 = letoh32(sc->sc_txdescs[j].tmd0);
1230 				else
1231 					tmd2 = letoh32(sc->sc_txdescs[j].tmd2);
1232 				if (tmd2 & LE_T2_UFLO) {
1233 					if (sc->sc_xmtsp < LE_C80_XMTSP_MAX) {
1234 						sc->sc_xmtsp++;
1235 						printf("%s: transmit "
1236 						    "underrun; new threshold: "
1237 						    "%s\n",
1238 						    sc->sc_dev.dv_xname,
1239 						    sc->sc_xmtsp_desc[
1240 						    sc->sc_xmtsp]);
1241 						pcn_spnd(sc);
1242 						pcn_csr_write(sc, LE_CSR80,
1243 						    LE_C80_RCVFW(sc->sc_rcvfw) |
1244 						    LE_C80_XMTSP(sc->sc_xmtsp) |
1245 						    LE_C80_XMTFW(sc->sc_xmtfw));
1246 						pcn_csr_write(sc, LE_CSR5,
1247 						    sc->sc_csr5);
1248 					} else {
1249 						printf("%s: transmit "
1250 						    "underrun\n",
1251 						    sc->sc_dev.dv_xname);
1252 					}
1253 				} else if (tmd2 & LE_T2_BUFF) {
1254 					printf("%s: transmit buffer error\n",
1255 					    sc->sc_dev.dv_xname);
1256 				}
1257 				if (tmd2 & LE_T2_LCOL)
1258 					ifp->if_collisions++;
1259 				if (tmd2 & LE_T2_RTRY)
1260 					ifp->if_collisions += 16;
1261 				goto next_packet;
1262 			}
1263 			if (j == txs->txs_lastdesc)
1264 				break;
1265 		}
1266 		if (tmd1 & LE_T1_ONE)
1267 			ifp->if_collisions++;
1268 		else if (tmd & LE_T1_MORE) {
1269 			/* Real number is unknown. */
1270 			ifp->if_collisions += 2;
1271 		}
1272 		ifp->if_opackets++;
1273  next_packet:
1274 		sc->sc_txfree += txs->txs_dmamap->dm_nsegs;
1275 		bus_dmamap_sync(sc->sc_dmat, txs->txs_dmamap,
1276 		    0, txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
1277 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1278 		m_freem(txs->txs_mbuf);
1279 		txs->txs_mbuf = NULL;
1280 	}
1281 
1282 	/* Update the dirty transmit buffer pointer. */
1283 	sc->sc_txsdirty = i;
1284 
1285 	/*
1286 	 * If there are no more pending transmissions, cancel the watchdog
1287 	 * timer.
1288 	 */
1289 	if (sc->sc_txsfree == PCN_TXQUEUELEN)
1290 		ifp->if_timer = 0;
1291 }
1292 
1293 /*
1294  * pcn_rxintr:
1295  *
1296  *	Helper; handle receive interrupts.
1297  */
1298 int
1299 pcn_rxintr(struct pcn_softc *sc)
1300 {
1301 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1302 	struct pcn_rxsoft *rxs;
1303 	struct mbuf *m;
1304 	struct mbuf_list ml = MBUF_LIST_INITIALIZER();
1305 	uint32_t rmd1;
1306 	int i, len;
1307 	int rv = 0;
1308 
1309 	for (i = sc->sc_rxptr;; i = PCN_NEXTRX(i)) {
1310 		rxs = &sc->sc_rxsoft[i];
1311 
1312 		PCN_CDRXSYNC(sc, i, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1313 
1314 		rmd1 = letoh32(sc->sc_rxdescs[i].rmd1);
1315 
1316 		if (rmd1 & LE_R1_OWN)
1317 			break;
1318 
1319 		/*
1320 		 * Check for errors and make sure the packet fit into
1321 		 * a single buffer.  We have structured this block of
1322 		 * code the way it is in order to compress it into
1323 		 * one test in the common case (no error).
1324 		 */
1325 		if (__predict_false((rmd1 & (LE_R1_STP|LE_R1_ENP|LE_R1_ERR)) !=
1326 		    (LE_R1_STP|LE_R1_ENP))) {
1327 			/* Make sure the packet is in a single buffer. */
1328 			if ((rmd1 & (LE_R1_STP|LE_R1_ENP)) !=
1329 			    (LE_R1_STP|LE_R1_ENP)) {
1330 				printf("%s: packet spilled into next buffer\n",
1331 				    sc->sc_dev.dv_xname);
1332 				rv = 1; /* pcn_intr() will re-init */
1333 				goto done;
1334 			}
1335 
1336 			/*
1337 			 * If the packet had an error, simple recycle the
1338 			 * buffer.
1339 			 */
1340 			if (rmd1 & LE_R1_ERR) {
1341 				ifp->if_ierrors++;
1342 				/*
1343 				 * If we got an overflow error, chances
1344 				 * are there will be a CRC error.  In
1345 				 * this case, just print the overflow
1346 				 * error, and skip the others.
1347 				 */
1348 				if (rmd1 & LE_R1_OFLO)
1349 					printf("%s: overflow error\n",
1350 					    sc->sc_dev.dv_xname);
1351 				else {
1352 #define	PRINTIT(x, str)							\
1353 					if (rmd1 & (x))			\
1354 						printf("%s: %s\n",	\
1355 						    sc->sc_dev.dv_xname, str);
1356 					PRINTIT(LE_R1_FRAM, "framing error");
1357 					PRINTIT(LE_R1_CRC, "CRC error");
1358 					PRINTIT(LE_R1_BUFF, "buffer error");
1359 				}
1360 #undef PRINTIT
1361 				PCN_INIT_RXDESC(sc, i);
1362 				continue;
1363 			}
1364 		}
1365 
1366 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1367 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1368 
1369 		/*
1370 		 * No errors; receive the packet.
1371 		 */
1372 		if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3)
1373 			len = letoh32(sc->sc_rxdescs[i].rmd0) & LE_R1_BCNT_MASK;
1374 		else
1375 			len = letoh32(sc->sc_rxdescs[i].rmd2) & LE_R1_BCNT_MASK;
1376 
1377 		/*
1378 		 * The LANCE family includes the CRC with every packet;
1379 		 * trim it off here.
1380 		 */
1381 		len -= ETHER_CRC_LEN;
1382 
1383 		/*
1384 		 * If the packet is small enough to fit in a
1385 		 * single header mbuf, allocate one and copy
1386 		 * the data into it.  This greatly reduces
1387 		 * memory consumption when we receive lots
1388 		 * of small packets.
1389 		 *
1390 		 * Otherwise, we add a new buffer to the receive
1391 		 * chain.  If this fails, we drop the packet and
1392 		 * recycle the old buffer.
1393 		 */
1394 		if (pcn_copy_small != 0 && len <= (MHLEN - 2)) {
1395 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1396 			if (m == NULL)
1397 				goto dropit;
1398 			m->m_data += 2;
1399 			memcpy(mtod(m, caddr_t),
1400 			    mtod(rxs->rxs_mbuf, caddr_t), len);
1401 			PCN_INIT_RXDESC(sc, i);
1402 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1403 			    rxs->rxs_dmamap->dm_mapsize,
1404 			    BUS_DMASYNC_PREREAD);
1405 		} else {
1406 			m = rxs->rxs_mbuf;
1407 			if (pcn_add_rxbuf(sc, i) != 0) {
1408  dropit:
1409 				ifp->if_ierrors++;
1410 				PCN_INIT_RXDESC(sc, i);
1411 				bus_dmamap_sync(sc->sc_dmat,
1412 				    rxs->rxs_dmamap, 0,
1413 				    rxs->rxs_dmamap->dm_mapsize,
1414 				    BUS_DMASYNC_PREREAD);
1415 				continue;
1416 			}
1417 		}
1418 
1419 		m->m_pkthdr.len = m->m_len = len;
1420 
1421 		ml_enqueue(&ml, m);
1422 	}
1423 
1424 	/* Update the receive pointer. */
1425 	sc->sc_rxptr = i;
1426 done:
1427 	if_input(ifp, &ml);
1428 	return (rv);
1429 }
1430 
1431 /*
1432  * pcn_tick:
1433  *
1434  *	One second timer, used to tick the MII.
1435  */
1436 void
1437 pcn_tick(void *arg)
1438 {
1439 	struct pcn_softc *sc = arg;
1440 	int s;
1441 
1442 	s = splnet();
1443 	mii_tick(&sc->sc_mii);
1444 	splx(s);
1445 
1446 	timeout_add_sec(&sc->sc_tick_timeout, 1);
1447 }
1448 
1449 /*
1450  * pcn_reset:
1451  *
1452  *	Perform a soft reset on the PCnet-PCI.
1453  */
1454 void
1455 pcn_reset(struct pcn_softc *sc)
1456 {
1457 
1458 	/*
1459 	 * The PCnet-PCI chip is reset by reading from the
1460 	 * RESET register.  Note that while the NE2100 LANCE
1461 	 * boards require a write after the read, the PCnet-PCI
1462 	 * chips do not require this.
1463 	 *
1464 	 * Since we don't know if we're in 16-bit or 32-bit
1465 	 * mode right now, issue both (it's safe) in the
1466 	 * hopes that one will succeed.
1467 	 */
1468 	(void) bus_space_read_2(sc->sc_st, sc->sc_sh, PCN16_RESET);
1469 	(void) bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_RESET);
1470 
1471 	/* Wait 1ms for it to finish. */
1472 	delay(1000);
1473 
1474 	/*
1475 	 * Select 32-bit I/O mode by issuing a 32-bit write to the
1476 	 * RDP.  Since the RAP is 0 after a reset, writing a 0
1477 	 * to RDP is safe (since it simply clears CSR0).
1478 	 */
1479 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RDP, 0);
1480 }
1481 
1482 /*
1483  * pcn_init:		[ifnet interface function]
1484  *
1485  *	Initialize the interface.  Must be called at splnet().
1486  */
1487 int
1488 pcn_init(struct ifnet *ifp)
1489 {
1490 	struct pcn_softc *sc = ifp->if_softc;
1491 	struct pcn_rxsoft *rxs;
1492 	uint8_t *enaddr = LLADDR(ifp->if_sadl);
1493 	int i, error = 0;
1494 	uint32_t reg;
1495 
1496 	/* Cancel any pending I/O. */
1497 	pcn_stop(ifp, 0);
1498 
1499 	/* Reset the chip to a known state. */
1500 	pcn_reset(sc);
1501 
1502 	/*
1503 	 * On the Am79c970, select SSTYLE 2, and SSTYLE 3 on everything
1504 	 * else.
1505 	 *
1506 	 * XXX It'd be really nice to use SSTYLE 2 on all the chips,
1507 	 * because the structure layout is compatible with ILACC,
1508 	 * but the burst mode is only available in SSTYLE 3, and
1509 	 * burst mode should provide some performance enhancement.
1510 	 */
1511 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970)
1512 		sc->sc_swstyle = LE_B20_SSTYLE_PCNETPCI2;
1513 	else
1514 		sc->sc_swstyle = LE_B20_SSTYLE_PCNETPCI3;
1515 	pcn_bcr_write(sc, LE_BCR20, sc->sc_swstyle);
1516 
1517 	/* Initialize the transmit descriptor ring. */
1518 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
1519 	PCN_CDTXSYNC(sc, 0, PCN_NTXDESC,
1520 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1521 	sc->sc_txfree = PCN_NTXDESC;
1522 	sc->sc_txnext = 0;
1523 
1524 	/* Initialize the transmit job descriptors. */
1525 	for (i = 0; i < PCN_TXQUEUELEN; i++)
1526 		sc->sc_txsoft[i].txs_mbuf = NULL;
1527 	sc->sc_txsfree = PCN_TXQUEUELEN;
1528 	sc->sc_txsnext = 0;
1529 	sc->sc_txsdirty = 0;
1530 
1531 	/*
1532 	 * Initialize the receive descriptor and receive job
1533 	 * descriptor rings.
1534 	 */
1535 	for (i = 0; i < PCN_NRXDESC; i++) {
1536 		rxs = &sc->sc_rxsoft[i];
1537 		if (rxs->rxs_mbuf == NULL) {
1538 			if ((error = pcn_add_rxbuf(sc, i)) != 0) {
1539 				printf("%s: unable to allocate or map rx "
1540 				    "buffer %d, error = %d\n",
1541 				    sc->sc_dev.dv_xname, i, error);
1542 				/*
1543 				 * XXX Should attempt to run with fewer receive
1544 				 * XXX buffers instead of just failing.
1545 				 */
1546 				pcn_rxdrain(sc);
1547 				goto out;
1548 			}
1549 		} else
1550 			PCN_INIT_RXDESC(sc, i);
1551 	}
1552 	sc->sc_rxptr = 0;
1553 
1554 	/* Initialize MODE for the initialization block. */
1555 	sc->sc_mode = 0;
1556 
1557 	/*
1558 	 * If we have MII, simply select MII in the MODE register,
1559 	 * and clear ASEL.  Otherwise, let ASEL stand (for now),
1560 	 * and leave PORTSEL alone (it is ignored with ASEL is set).
1561 	 */
1562 	if (sc->sc_flags & PCN_F_HAS_MII) {
1563 		pcn_bcr_write(sc, LE_BCR2,
1564 		    pcn_bcr_read(sc, LE_BCR2) & ~LE_B2_ASEL);
1565 		sc->sc_mode |= LE_C15_PORTSEL(PORTSEL_MII);
1566 
1567 		/*
1568 		 * Disable MII auto-negotiation.  We handle that in
1569 		 * our own MII layer.
1570 		 */
1571 		pcn_bcr_write(sc, LE_BCR32,
1572 		    pcn_bcr_read(sc, LE_BCR32) | LE_B32_DANAS);
1573 	}
1574 
1575 	/* Set the multicast filter in the init block. */
1576 	pcn_set_filter(sc);
1577 
1578 	/*
1579 	 * Set the Tx and Rx descriptor ring addresses in the init
1580 	 * block, the TLEN and RLEN other fields of the init block
1581 	 * MODE register.
1582 	 */
1583 	sc->sc_initblock.init_rdra = htole32(PCN_CDRXADDR(sc, 0));
1584 	sc->sc_initblock.init_tdra = htole32(PCN_CDTXADDR(sc, 0));
1585 	sc->sc_initblock.init_mode = htole32(sc->sc_mode |
1586 	    ((ffs(PCN_NTXDESC) - 1) << 28) |
1587 	    ((ffs(PCN_NRXDESC) - 1) << 20));
1588 
1589 	/* Set the station address in the init block. */
1590 	sc->sc_initblock.init_padr[0] = htole32(enaddr[0] |
1591 	    (enaddr[1] << 8) | (enaddr[2] << 16) | (enaddr[3] << 24));
1592 	sc->sc_initblock.init_padr[1] = htole32(enaddr[4] |
1593 	    (enaddr[5] << 8));
1594 
1595 	/* Initialize CSR3. */
1596 	pcn_csr_write(sc, LE_CSR3, LE_C3_MISSM|LE_C3_IDONM|LE_C3_DXSUFLO);
1597 
1598 	/* Initialize CSR4. */
1599 	pcn_csr_write(sc, LE_CSR4, LE_C4_DMAPLUS|LE_C4_APAD_XMT|
1600 	    LE_C4_MFCOM|LE_C4_RCVCCOM|LE_C4_TXSTRTM);
1601 
1602 	/* Initialize CSR5. */
1603 	sc->sc_csr5 = LE_C5_LTINTEN|LE_C5_SINTE;
1604 	pcn_csr_write(sc, LE_CSR5, sc->sc_csr5);
1605 
1606 	/*
1607 	 * If we have an Am79c971 or greater, initialize CSR7.
1608 	 *
1609 	 * XXX Might be nice to use the MII auto-poll interrupt someday.
1610 	 */
1611 	switch (sc->sc_variant->pcv_chipid) {
1612 	case PARTID_Am79c970:
1613 	case PARTID_Am79c970A:
1614 		/* Not available on these chips. */
1615 		break;
1616 
1617 	default:
1618 		pcn_csr_write(sc, LE_CSR7, LE_C7_FASTSPNDE);
1619 		break;
1620 	}
1621 
1622 	/*
1623 	 * On the Am79c970A and greater, initialize BCR18 to
1624 	 * enable burst mode.
1625 	 *
1626 	 * Also enable the "no underflow" option on the Am79c971 and
1627 	 * higher, which prevents the chip from generating transmit
1628 	 * underflows, yet sill provides decent performance.  Note if
1629 	 * chip is not connected to external SRAM, then we still have
1630 	 * to handle underflow errors (the NOUFLO bit is ignored in
1631 	 * that case).
1632 	 */
1633 	reg = pcn_bcr_read(sc, LE_BCR18);
1634 	switch (sc->sc_variant->pcv_chipid) {
1635 	case PARTID_Am79c970:
1636 		break;
1637 
1638 	case PARTID_Am79c970A:
1639 		reg |= LE_B18_BREADE|LE_B18_BWRITE;
1640 		break;
1641 
1642 	default:
1643 		reg |= LE_B18_BREADE|LE_B18_BWRITE|LE_B18_NOUFLO;
1644 		break;
1645 	}
1646 	pcn_bcr_write(sc, LE_BCR18, reg);
1647 
1648 	/*
1649 	 * Initialize CSR80 (FIFO thresholds for Tx and Rx).
1650 	 */
1651 	pcn_csr_write(sc, LE_CSR80, LE_C80_RCVFW(sc->sc_rcvfw) |
1652 	    LE_C80_XMTSP(sc->sc_xmtsp) | LE_C80_XMTFW(sc->sc_xmtfw));
1653 
1654 	/*
1655 	 * Send the init block to the chip, and wait for it
1656 	 * to be processed.
1657 	 */
1658 	PCN_CDINITSYNC(sc, BUS_DMASYNC_PREWRITE);
1659 	pcn_csr_write(sc, LE_CSR1, PCN_CDINITADDR(sc) & 0xffff);
1660 	pcn_csr_write(sc, LE_CSR2, (PCN_CDINITADDR(sc) >> 16) & 0xffff);
1661 	pcn_csr_write(sc, LE_CSR0, LE_C0_INIT);
1662 	delay(100);
1663 	for (i = 0; i < 10000; i++) {
1664 		if (pcn_csr_read(sc, LE_CSR0) & LE_C0_IDON)
1665 			break;
1666 		delay(10);
1667 	}
1668 	PCN_CDINITSYNC(sc, BUS_DMASYNC_POSTWRITE);
1669 	if (i == 10000) {
1670 		printf("%s: timeout processing init block\n",
1671 		    sc->sc_dev.dv_xname);
1672 		error = EIO;
1673 		goto out;
1674 	}
1675 
1676 	/* Set the media. */
1677 	(void) (*sc->sc_mii.mii_media.ifm_change)(ifp);
1678 
1679 	/* Enable interrupts and external activity (and ACK IDON). */
1680 	pcn_csr_write(sc, LE_CSR0, LE_C0_INEA|LE_C0_STRT|LE_C0_IDON);
1681 
1682 	if (sc->sc_flags & PCN_F_HAS_MII) {
1683 		/* Start the one second MII clock. */
1684 		timeout_add_sec(&sc->sc_tick_timeout, 1);
1685 	}
1686 
1687 	/* ...all done! */
1688 	ifp->if_flags |= IFF_RUNNING;
1689 	ifq_clr_oactive(&ifp->if_snd);
1690 
1691  out:
1692 	if (error)
1693 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
1694 	return (error);
1695 }
1696 
1697 /*
1698  * pcn_rxdrain:
1699  *
1700  *	Drain the receive queue.
1701  */
1702 void
1703 pcn_rxdrain(struct pcn_softc *sc)
1704 {
1705 	struct pcn_rxsoft *rxs;
1706 	int i;
1707 
1708 	for (i = 0; i < PCN_NRXDESC; i++) {
1709 		rxs = &sc->sc_rxsoft[i];
1710 		if (rxs->rxs_mbuf != NULL) {
1711 			bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1712 			m_freem(rxs->rxs_mbuf);
1713 			rxs->rxs_mbuf = NULL;
1714 		}
1715 	}
1716 }
1717 
1718 /*
1719  * pcn_stop:		[ifnet interface function]
1720  *
1721  *	Stop transmission on the interface.
1722  */
1723 void
1724 pcn_stop(struct ifnet *ifp, int disable)
1725 {
1726 	struct pcn_softc *sc = ifp->if_softc;
1727 	struct pcn_txsoft *txs;
1728 	int i;
1729 
1730 	if (sc->sc_flags & PCN_F_HAS_MII) {
1731 		/* Stop the one second clock. */
1732 		timeout_del(&sc->sc_tick_timeout);
1733 
1734 		/* Down the MII. */
1735 		mii_down(&sc->sc_mii);
1736 	}
1737 
1738 	/* Mark the interface as down and cancel the watchdog timer. */
1739 	ifp->if_flags &= ~IFF_RUNNING;
1740 	ifq_clr_oactive(&ifp->if_snd);
1741 	ifp->if_timer = 0;
1742 
1743 	/* Stop the chip. */
1744 	pcn_csr_write(sc, LE_CSR0, LE_C0_STOP);
1745 
1746 	/* Release any queued transmit buffers. */
1747 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
1748 		txs = &sc->sc_txsoft[i];
1749 		if (txs->txs_mbuf != NULL) {
1750 			bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1751 			m_freem(txs->txs_mbuf);
1752 			txs->txs_mbuf = NULL;
1753 		}
1754 	}
1755 
1756 	if (disable)
1757 		pcn_rxdrain(sc);
1758 }
1759 
1760 /*
1761  * pcn_add_rxbuf:
1762  *
1763  *	Add a receive buffer to the indicated descriptor.
1764  */
1765 int
1766 pcn_add_rxbuf(struct pcn_softc *sc, int idx)
1767 {
1768 	struct pcn_rxsoft *rxs = &sc->sc_rxsoft[idx];
1769 	struct mbuf *m;
1770 	int error;
1771 
1772 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1773 	if (m == NULL)
1774 		return (ENOBUFS);
1775 
1776 	MCLGET(m, M_DONTWAIT);
1777 	if ((m->m_flags & M_EXT) == 0) {
1778 		m_freem(m);
1779 		return (ENOBUFS);
1780 	}
1781 
1782 	if (rxs->rxs_mbuf != NULL)
1783 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1784 
1785 	rxs->rxs_mbuf = m;
1786 
1787 	error = bus_dmamap_load(sc->sc_dmat, rxs->rxs_dmamap,
1788 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1789 	    BUS_DMA_READ|BUS_DMA_NOWAIT);
1790 	if (error) {
1791 		printf("%s: can't load rx DMA map %d, error = %d\n",
1792 		    sc->sc_dev.dv_xname, idx, error);
1793 		panic("pcn_add_rxbuf");
1794 	}
1795 
1796 	bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1797 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1798 
1799 	PCN_INIT_RXDESC(sc, idx);
1800 
1801 	return (0);
1802 }
1803 
1804 /*
1805  * pcn_set_filter:
1806  *
1807  *	Set up the receive filter.
1808  */
1809 void
1810 pcn_set_filter(struct pcn_softc *sc)
1811 {
1812 	struct arpcom *ac = &sc->sc_arpcom;
1813 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1814 	struct ether_multi *enm;
1815 	struct ether_multistep step;
1816 	uint32_t crc;
1817 
1818 	ifp->if_flags &= ~IFF_ALLMULTI;
1819 
1820 	if (ifp->if_flags & IFF_PROMISC || ac->ac_multirangecnt > 0) {
1821 		ifp->if_flags |= IFF_ALLMULTI;
1822 		if (ifp->if_flags & IFF_PROMISC)
1823 			sc->sc_mode |= LE_C15_PROM;
1824 		sc->sc_initblock.init_ladrf[0] =
1825 		    sc->sc_initblock.init_ladrf[1] =
1826 		    sc->sc_initblock.init_ladrf[2] =
1827 		    sc->sc_initblock.init_ladrf[3] = 0xffff;
1828 	} else {
1829 		sc->sc_initblock.init_ladrf[0] =
1830 		    sc->sc_initblock.init_ladrf[1] =
1831 		    sc->sc_initblock.init_ladrf[2] =
1832 		    sc->sc_initblock.init_ladrf[3] = 0;
1833 
1834 		/*
1835 		 * Set up the multicast address filter by passing all multicast
1836 		 * addresses through a CRC generator, and then using the high
1837 		 * order 6 bits as an index into the 64-bit logical address
1838 		 * filter.  The high order bits select the word, while the rest
1839 		 * of the bits select the bit within the word.
1840 		 */
1841 		ETHER_FIRST_MULTI(step, ac, enm);
1842 		while (enm != NULL) {
1843 			crc = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN);
1844 
1845 			/* Just want the 6 most significant bits. */
1846 			crc >>= 26;
1847 
1848 			/* Set the corresponding bit in the filter. */
1849 			sc->sc_initblock.init_ladrf[crc >> 4] |=
1850 			    htole16(1 << (crc & 0xf));
1851 
1852 			ETHER_NEXT_MULTI(step, enm);
1853 		}
1854 	}
1855 }
1856 
1857 /*
1858  * pcn_79c970_mediainit:
1859  *
1860  *	Initialize media for the Am79c970.
1861  */
1862 void
1863 pcn_79c970_mediainit(struct pcn_softc *sc)
1864 {
1865 	ifmedia_init(&sc->sc_mii.mii_media, IFM_IMASK, pcn_79c970_mediachange,
1866 	    pcn_79c970_mediastatus);
1867 
1868 	ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_10_5,
1869 	    PORTSEL_AUI, NULL);
1870 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
1871 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_10_5|IFM_FDX,
1872 		    PORTSEL_AUI, NULL);
1873 
1874 	ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_10_T,
1875 	    PORTSEL_10T, NULL);
1876 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
1877 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_10_T|IFM_FDX,
1878 		    PORTSEL_10T, NULL);
1879 
1880 	ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO,
1881 	    0, NULL);
1882 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
1883 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO|IFM_FDX,
1884 		    0, NULL);
1885 
1886 	ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
1887 }
1888 
1889 /*
1890  * pcn_79c970_mediastatus:	[ifmedia interface function]
1891  *
1892  *	Get the current interface media status (Am79c970 version).
1893  */
1894 void
1895 pcn_79c970_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
1896 {
1897 	struct pcn_softc *sc = ifp->if_softc;
1898 
1899 	/*
1900 	 * The currently selected media is always the active media.
1901 	 * Note: We have no way to determine what media the AUTO
1902 	 * process picked.
1903 	 */
1904 	ifmr->ifm_active = sc->sc_mii.mii_media.ifm_media;
1905 }
1906 
1907 /*
1908  * pcn_79c970_mediachange:	[ifmedia interface function]
1909  *
1910  *	Set hardware to newly-selected media (Am79c970 version).
1911  */
1912 int
1913 pcn_79c970_mediachange(struct ifnet *ifp)
1914 {
1915 	struct pcn_softc *sc = ifp->if_softc;
1916 	uint32_t reg;
1917 
1918 	if (IFM_SUBTYPE(sc->sc_mii.mii_media.ifm_media) == IFM_AUTO) {
1919 		/*
1920 		 * CSR15:PORTSEL doesn't matter.  Just set BCR2:ASEL.
1921 		 */
1922 		reg = pcn_bcr_read(sc, LE_BCR2);
1923 		reg |= LE_B2_ASEL;
1924 		pcn_bcr_write(sc, LE_BCR2, reg);
1925 	} else {
1926 		/*
1927 		 * Clear BCR2:ASEL and set the new CSR15:PORTSEL value.
1928 		 */
1929 		reg = pcn_bcr_read(sc, LE_BCR2);
1930 		reg &= ~LE_B2_ASEL;
1931 		pcn_bcr_write(sc, LE_BCR2, reg);
1932 
1933 		reg = pcn_csr_read(sc, LE_CSR15);
1934 		reg = (reg & ~LE_C15_PORTSEL(PORTSEL_MASK)) |
1935 		    LE_C15_PORTSEL(sc->sc_mii.mii_media.ifm_cur->ifm_data);
1936 		pcn_csr_write(sc, LE_CSR15, reg);
1937 	}
1938 
1939 	if ((sc->sc_mii.mii_media.ifm_media & IFM_FDX) != 0) {
1940 		reg = LE_B9_FDEN;
1941 		if (IFM_SUBTYPE(sc->sc_mii.mii_media.ifm_media) == IFM_10_5)
1942 			reg |= LE_B9_AUIFD;
1943 		pcn_bcr_write(sc, LE_BCR9, reg);
1944 	} else
1945 		pcn_bcr_write(sc, LE_BCR9, 0);
1946 
1947 	return (0);
1948 }
1949 
1950 /*
1951  * pcn_79c971_mediainit:
1952  *
1953  *	Initialize media for the Am79c971.
1954  */
1955 void
1956 pcn_79c971_mediainit(struct pcn_softc *sc)
1957 {
1958 	struct ifnet *ifp = &sc->sc_arpcom.ac_if;
1959 
1960 	/* We have MII. */
1961 	sc->sc_flags |= PCN_F_HAS_MII;
1962 
1963 	/*
1964 	 * The built-in 10BASE-T interface is mapped to the MII
1965 	 * on the PCNet-FAST.  Unfortunately, there's no EEPROM
1966 	 * word that tells us which PHY to use.
1967 	 * This driver used to ignore all but the first PHY to
1968 	 * answer, but this code was removed to support multiple
1969 	 * external PHYs. As the default instance will be the first
1970 	 * one to answer, no harm is done by letting the possibly
1971 	 * non-connected internal PHY show up.
1972 	 */
1973 
1974 	/* Initialize our media structures and probe the MII. */
1975 	sc->sc_mii.mii_ifp = ifp;
1976 	sc->sc_mii.mii_readreg = pcn_mii_readreg;
1977 	sc->sc_mii.mii_writereg = pcn_mii_writereg;
1978 	sc->sc_mii.mii_statchg = pcn_mii_statchg;
1979 	ifmedia_init(&sc->sc_mii.mii_media, 0, pcn_79c971_mediachange,
1980 	    pcn_79c971_mediastatus);
1981 
1982 	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
1983 	    MII_OFFSET_ANY, 0);
1984 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
1985 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
1986 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
1987 	} else
1988 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
1989 }
1990 
1991 /*
1992  * pcn_79c971_mediastatus:	[ifmedia interface function]
1993  *
1994  *	Get the current interface media status (Am79c971 version).
1995  */
1996 void
1997 pcn_79c971_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
1998 {
1999 	struct pcn_softc *sc = ifp->if_softc;
2000 
2001 	mii_pollstat(&sc->sc_mii);
2002 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
2003 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
2004 }
2005 
2006 /*
2007  * pcn_79c971_mediachange:	[ifmedia interface function]
2008  *
2009  *	Set hardware to newly-selected media (Am79c971 version).
2010  */
2011 int
2012 pcn_79c971_mediachange(struct ifnet *ifp)
2013 {
2014 	struct pcn_softc *sc = ifp->if_softc;
2015 
2016 	if (ifp->if_flags & IFF_UP)
2017 		mii_mediachg(&sc->sc_mii);
2018 	return (0);
2019 }
2020 
2021 /*
2022  * pcn_mii_readreg:	[mii interface function]
2023  *
2024  *	Read a PHY register on the MII.
2025  */
2026 int
2027 pcn_mii_readreg(struct device *self, int phy, int reg)
2028 {
2029 	struct pcn_softc *sc = (void *) self;
2030 	uint32_t rv;
2031 
2032 	pcn_bcr_write(sc, LE_BCR33, reg | (phy << PHYAD_SHIFT));
2033 	rv = pcn_bcr_read(sc, LE_BCR34) & LE_B34_MIIMD;
2034 	if (rv == 0xffff)
2035 		return (0);
2036 
2037 	return (rv);
2038 }
2039 
2040 /*
2041  * pcn_mii_writereg:	[mii interface function]
2042  *
2043  *	Write a PHY register on the MII.
2044  */
2045 void
2046 pcn_mii_writereg(struct device *self, int phy, int reg, int val)
2047 {
2048 	struct pcn_softc *sc = (void *) self;
2049 
2050 	pcn_bcr_write(sc, LE_BCR33, reg | (phy << PHYAD_SHIFT));
2051 	pcn_bcr_write(sc, LE_BCR34, val);
2052 }
2053 
2054 /*
2055  * pcn_mii_statchg:	[mii interface function]
2056  *
2057  *	Callback from MII layer when media changes.
2058  */
2059 void
2060 pcn_mii_statchg(struct device *self)
2061 {
2062 	struct pcn_softc *sc = (void *) self;
2063 
2064 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0)
2065 		pcn_bcr_write(sc, LE_BCR9, LE_B9_FDEN);
2066 	else
2067 		pcn_bcr_write(sc, LE_BCR9, 0);
2068 }
2069