xref: /netbsd-src/sys/dev/pci/if_pcn.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: if_pcn.c,v 1.41 2007/10/19 12:00:47 ad Exp $	*/
2 
3 /*
4  * Copyright (c) 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed for the NetBSD Project by
20  *	Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*
39  * Device driver for the AMD PCnet-PCI series of Ethernet
40  * chips:
41  *
42  *	* Am79c970 PCnet-PCI Single-Chip Ethernet Controller for PCI
43  *	  Local Bus
44  *
45  *	* Am79c970A PCnet-PCI II Single-Chip Full-Duplex Ethernet Controller
46  *	  for PCI Local Bus
47  *
48  *	* Am79c971 PCnet-FAST Single-Chip Full-Duplex 10/100Mbps
49  *	  Ethernet Controller for PCI Local Bus
50  *
51  *	* Am79c972 PCnet-FAST+ Enhanced 10/100Mbps PCI Ethernet Controller
52  *	  with OnNow Support
53  *
54  *	* Am79c973/Am79c975 PCnet-FAST III Single-Chip 10/100Mbps PCI
55  *	  Ethernet Controller with Integrated PHY
56  *
57  * This also supports the virtual PCnet-PCI Ethernet interface found
58  * in VMware.
59  *
60  * TODO:
61  *
62  *	* Split this into bus-specific and bus-independent portions.
63  *	  The core could also be used for the ILACC (Am79900) 32-bit
64  *	  Ethernet chip (XXX only if we use an ILACC-compatible SWSTYLE).
65  */
66 
67 #include <sys/cdefs.h>
68 __KERNEL_RCSID(0, "$NetBSD: if_pcn.c,v 1.41 2007/10/19 12:00:47 ad Exp $");
69 
70 #include "bpfilter.h"
71 #include "rnd.h"
72 
73 #include <sys/param.h>
74 #include <sys/systm.h>
75 #include <sys/callout.h>
76 #include <sys/mbuf.h>
77 #include <sys/malloc.h>
78 #include <sys/kernel.h>
79 #include <sys/socket.h>
80 #include <sys/ioctl.h>
81 #include <sys/errno.h>
82 #include <sys/device.h>
83 #include <sys/queue.h>
84 
85 #if NRND > 0
86 #include <sys/rnd.h>
87 #endif
88 
89 #include <uvm/uvm_extern.h>		/* for PAGE_SIZE */
90 
91 #include <net/if.h>
92 #include <net/if_dl.h>
93 #include <net/if_media.h>
94 #include <net/if_ether.h>
95 
96 #if NBPFILTER > 0
97 #include <net/bpf.h>
98 #endif
99 
100 #include <sys/bus.h>
101 #include <sys/intr.h>
102 #include <machine/endian.h>
103 
104 #include <dev/mii/mii.h>
105 #include <dev/mii/miivar.h>
106 
107 #include <dev/ic/am79900reg.h>
108 #include <dev/ic/lancereg.h>
109 
110 #include <dev/pci/pcireg.h>
111 #include <dev/pci/pcivar.h>
112 #include <dev/pci/pcidevs.h>
113 
114 #include <dev/pci/if_pcnreg.h>
115 
116 /*
117  * Transmit descriptor list size.  This is arbitrary, but allocate
118  * enough descriptors for 128 pending transmissions, and 4 segments
119  * per packet.  This MUST work out to a power of 2.
120  *
121  * NOTE: We can't have any more than 512 Tx descriptors, SO BE CAREFUL!
122  *
123  * So we play a little trick here.  We give each packet up to 16
124  * DMA segments, but only allocate the max of 512 descriptors.  The
125  * transmit logic can deal with this, we just are hoping to sneak by.
126  */
127 #define	PCN_NTXSEGS		16
128 #define	PCN_NTXSEGS_VMWARE	8	/* bug in VMware's emulation */
129 
130 #define	PCN_TXQUEUELEN		128
131 #define	PCN_TXQUEUELEN_MASK	(PCN_TXQUEUELEN - 1)
132 #define	PCN_NTXDESC		512
133 #define	PCN_NTXDESC_MASK	(PCN_NTXDESC - 1)
134 #define	PCN_NEXTTX(x)		(((x) + 1) & PCN_NTXDESC_MASK)
135 #define	PCN_NEXTTXS(x)		(((x) + 1) & PCN_TXQUEUELEN_MASK)
136 
137 /* Tx interrupt every N + 1 packets. */
138 #define	PCN_TXINTR_MASK		7
139 
140 /*
141  * Receive descriptor list size.  We have one Rx buffer per incoming
142  * packet, so this logic is a little simpler.
143  */
144 #define	PCN_NRXDESC		128
145 #define	PCN_NRXDESC_MASK	(PCN_NRXDESC - 1)
146 #define	PCN_NEXTRX(x)		(((x) + 1) & PCN_NRXDESC_MASK)
147 
148 /*
149  * Control structures are DMA'd to the PCnet chip.  We allocate them in
150  * a single clump that maps to a single DMA segment to make several things
151  * easier.
152  */
153 struct pcn_control_data {
154 	/* The transmit descriptors. */
155 	struct letmd pcd_txdescs[PCN_NTXDESC];
156 
157 	/* The receive descriptors. */
158 	struct lermd pcd_rxdescs[PCN_NRXDESC];
159 
160 	/* The init block. */
161 	struct leinit pcd_initblock;
162 };
163 
164 #define	PCN_CDOFF(x)	offsetof(struct pcn_control_data, x)
165 #define	PCN_CDTXOFF(x)	PCN_CDOFF(pcd_txdescs[(x)])
166 #define	PCN_CDRXOFF(x)	PCN_CDOFF(pcd_rxdescs[(x)])
167 #define	PCN_CDINITOFF	PCN_CDOFF(pcd_initblock)
168 
169 /*
170  * Software state for transmit jobs.
171  */
172 struct pcn_txsoft {
173 	struct mbuf *txs_mbuf;		/* head of our mbuf chain */
174 	bus_dmamap_t txs_dmamap;	/* our DMA map */
175 	int txs_firstdesc;		/* first descriptor in packet */
176 	int txs_lastdesc;		/* last descriptor in packet */
177 };
178 
179 /*
180  * Software state for receive jobs.
181  */
182 struct pcn_rxsoft {
183 	struct mbuf *rxs_mbuf;		/* head of our mbuf chain */
184 	bus_dmamap_t rxs_dmamap;	/* our DMA map */
185 };
186 
187 /*
188  * Description of Rx FIFO watermarks for various revisions.
189  */
190 static const char * const pcn_79c970_rcvfw[] = {
191 	"16 bytes",
192 	"64 bytes",
193 	"128 bytes",
194 	NULL,
195 };
196 
197 static const char * const pcn_79c971_rcvfw[] = {
198 	"16 bytes",
199 	"64 bytes",
200 	"112 bytes",
201 	NULL,
202 };
203 
204 /*
205  * Description of Tx start points for various revisions.
206  */
207 static const char * const pcn_79c970_xmtsp[] = {
208 	"8 bytes",
209 	"64 bytes",
210 	"128 bytes",
211 	"248 bytes",
212 };
213 
214 static const char * const pcn_79c971_xmtsp[] = {
215 	"20 bytes",
216 	"64 bytes",
217 	"128 bytes",
218 	"248 bytes",
219 };
220 
221 static const char * const pcn_79c971_xmtsp_sram[] = {
222 	"44 bytes",
223 	"64 bytes",
224 	"128 bytes",
225 	"store-and-forward",
226 };
227 
228 /*
229  * Description of Tx FIFO watermarks for various revisions.
230  */
231 static const char * const pcn_79c970_xmtfw[] = {
232 	"16 bytes",
233 	"64 bytes",
234 	"128 bytes",
235 	NULL,
236 };
237 
238 static const char * const pcn_79c971_xmtfw[] = {
239 	"16 bytes",
240 	"64 bytes",
241 	"108 bytes",
242 	NULL,
243 };
244 
245 /*
246  * Software state per device.
247  */
248 struct pcn_softc {
249 	struct device sc_dev;		/* generic device information */
250 	bus_space_tag_t sc_st;		/* bus space tag */
251 	bus_space_handle_t sc_sh;	/* bus space handle */
252 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
253 	struct ethercom sc_ethercom;	/* Ethernet common data */
254 	void *sc_sdhook;		/* shutdown hook */
255 
256 	/* Points to our media routines, etc. */
257 	const struct pcn_variant *sc_variant;
258 
259 	void *sc_ih;			/* interrupt cookie */
260 
261 	struct mii_data sc_mii;		/* MII/media information */
262 
263 	callout_t sc_tick_ch;		/* tick callout */
264 
265 	bus_dmamap_t sc_cddmamap;	/* control data DMA map */
266 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
267 
268 	/* Software state for transmit and receive descriptors. */
269 	struct pcn_txsoft sc_txsoft[PCN_TXQUEUELEN];
270 	struct pcn_rxsoft sc_rxsoft[PCN_NRXDESC];
271 
272 	/* Control data structures */
273 	struct pcn_control_data *sc_control_data;
274 #define	sc_txdescs	sc_control_data->pcd_txdescs
275 #define	sc_rxdescs	sc_control_data->pcd_rxdescs
276 #define	sc_initblock	sc_control_data->pcd_initblock
277 
278 #ifdef PCN_EVENT_COUNTERS
279 	/* Event counters. */
280 	struct evcnt sc_ev_txsstall;	/* Tx stalled due to no txs */
281 	struct evcnt sc_ev_txdstall;	/* Tx stalled due to no txd */
282 	struct evcnt sc_ev_txintr;	/* Tx interrupts */
283 	struct evcnt sc_ev_rxintr;	/* Rx interrupts */
284 	struct evcnt sc_ev_babl;	/* BABL in pcn_intr() */
285 	struct evcnt sc_ev_miss;	/* MISS in pcn_intr() */
286 	struct evcnt sc_ev_merr;	/* MERR in pcn_intr() */
287 
288 	struct evcnt sc_ev_txseg1;	/* Tx packets w/ 1 segment */
289 	struct evcnt sc_ev_txseg2;	/* Tx packets w/ 2 segments */
290 	struct evcnt sc_ev_txseg3;	/* Tx packets w/ 3 segments */
291 	struct evcnt sc_ev_txseg4;	/* Tx packets w/ 4 segments */
292 	struct evcnt sc_ev_txseg5;	/* Tx packets w/ 5 segments */
293 	struct evcnt sc_ev_txsegmore;	/* Tx packets w/ more than 5 segments */
294 	struct evcnt sc_ev_txcopy;	/* Tx copies required */
295 #endif /* PCN_EVENT_COUNTERS */
296 
297 	const char * const *sc_rcvfw_desc;	/* Rx FIFO watermark info */
298 	int sc_rcvfw;
299 
300 	const char * const *sc_xmtsp_desc;	/* Tx start point info */
301 	int sc_xmtsp;
302 
303 	const char * const *sc_xmtfw_desc;	/* Tx FIFO watermark info */
304 	int sc_xmtfw;
305 
306 	int sc_flags;			/* misc. flags; see below */
307 	int sc_swstyle;			/* the software style in use */
308 
309 	int sc_txfree;			/* number of free Tx descriptors */
310 	int sc_txnext;			/* next ready Tx descriptor */
311 
312 	int sc_txsfree;			/* number of free Tx jobs */
313 	int sc_txsnext;			/* next free Tx job */
314 	int sc_txsdirty;		/* dirty Tx jobs */
315 
316 	int sc_rxptr;			/* next ready Rx descriptor/job */
317 
318 	uint32_t sc_csr5;		/* prototype CSR5 register */
319 	uint32_t sc_mode;		/* prototype MODE register */
320 
321 #if NRND > 0
322 	rndsource_element_t rnd_source;	/* random source */
323 #endif
324 };
325 
326 /* sc_flags */
327 #define	PCN_F_HAS_MII		0x0001	/* has MII */
328 
329 #ifdef PCN_EVENT_COUNTERS
330 #define	PCN_EVCNT_INCR(ev)	(ev)->ev_count++
331 #else
332 #define	PCN_EVCNT_INCR(ev)	/* nothing */
333 #endif
334 
335 #define	PCN_CDTXADDR(sc, x)	((sc)->sc_cddma + PCN_CDTXOFF((x)))
336 #define	PCN_CDRXADDR(sc, x)	((sc)->sc_cddma + PCN_CDRXOFF((x)))
337 #define	PCN_CDINITADDR(sc)	((sc)->sc_cddma + PCN_CDINITOFF)
338 
339 #define	PCN_CDTXSYNC(sc, x, n, ops)					\
340 do {									\
341 	int __x, __n;							\
342 									\
343 	__x = (x);							\
344 	__n = (n);							\
345 									\
346 	/* If it will wrap around, sync to the end of the ring. */	\
347 	if ((__x + __n) > PCN_NTXDESC) {				\
348 		bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,	\
349 		    PCN_CDTXOFF(__x), sizeof(struct letmd) *		\
350 		    (PCN_NTXDESC - __x), (ops));			\
351 		__n -= (PCN_NTXDESC - __x);				\
352 		__x = 0;						\
353 	}								\
354 									\
355 	/* Now sync whatever is left. */				\
356 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
357 	    PCN_CDTXOFF(__x), sizeof(struct letmd) * __n, (ops));	\
358 } while (/*CONSTCOND*/0)
359 
360 #define	PCN_CDRXSYNC(sc, x, ops)					\
361 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
362 	    PCN_CDRXOFF((x)), sizeof(struct lermd), (ops))
363 
364 #define	PCN_CDINITSYNC(sc, ops)						\
365 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
366 	    PCN_CDINITOFF, sizeof(struct leinit), (ops))
367 
368 #define	PCN_INIT_RXDESC(sc, x)						\
369 do {									\
370 	struct pcn_rxsoft *__rxs = &(sc)->sc_rxsoft[(x)];		\
371 	struct lermd *__rmd = &(sc)->sc_rxdescs[(x)];			\
372 	struct mbuf *__m = __rxs->rxs_mbuf;				\
373 									\
374 	/*								\
375 	 * Note: We scoot the packet forward 2 bytes in the buffer	\
376 	 * so that the payload after the Ethernet header is aligned	\
377 	 * to a 4-byte boundary.					\
378 	 */								\
379 	__m->m_data = __m->m_ext.ext_buf + 2;				\
380 									\
381 	if ((sc)->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3) {		\
382 		__rmd->rmd2 =						\
383 		    htole32(__rxs->rxs_dmamap->dm_segs[0].ds_addr + 2);	\
384 		__rmd->rmd0 = 0;					\
385 	} else {							\
386 		__rmd->rmd2 = 0;					\
387 		__rmd->rmd0 =						\
388 		    htole32(__rxs->rxs_dmamap->dm_segs[0].ds_addr + 2);	\
389 	}								\
390 	__rmd->rmd1 = htole32(LE_R1_OWN|LE_R1_ONES| 			\
391 	    (LE_BCNT(MCLBYTES - 2) & LE_R1_BCNT_MASK));			\
392 	PCN_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);\
393 } while(/*CONSTCOND*/0)
394 
395 static void	pcn_start(struct ifnet *);
396 static void	pcn_watchdog(struct ifnet *);
397 static int	pcn_ioctl(struct ifnet *, u_long, void *);
398 static int	pcn_init(struct ifnet *);
399 static void	pcn_stop(struct ifnet *, int);
400 
401 static void	pcn_shutdown(void *);
402 
403 static void	pcn_reset(struct pcn_softc *);
404 static void	pcn_rxdrain(struct pcn_softc *);
405 static int	pcn_add_rxbuf(struct pcn_softc *, int);
406 static void	pcn_tick(void *);
407 
408 static void	pcn_spnd(struct pcn_softc *);
409 
410 static void	pcn_set_filter(struct pcn_softc *);
411 
412 static int	pcn_intr(void *);
413 static void	pcn_txintr(struct pcn_softc *);
414 static int	pcn_rxintr(struct pcn_softc *);
415 
416 static int	pcn_mii_readreg(struct device *, int, int);
417 static void	pcn_mii_writereg(struct device *, int, int, int);
418 static void	pcn_mii_statchg(struct device *);
419 
420 static void	pcn_79c970_mediainit(struct pcn_softc *);
421 static int	pcn_79c970_mediachange(struct ifnet *);
422 static void	pcn_79c970_mediastatus(struct ifnet *, struct ifmediareq *);
423 
424 static void	pcn_79c971_mediainit(struct pcn_softc *);
425 static int	pcn_79c971_mediachange(struct ifnet *);
426 static void	pcn_79c971_mediastatus(struct ifnet *, struct ifmediareq *);
427 
428 /*
429  * Description of a PCnet-PCI variant.  Used to select media access
430  * method, mostly, and to print a nice description of the chip.
431  */
432 static const struct pcn_variant {
433 	const char *pcv_desc;
434 	void (*pcv_mediainit)(struct pcn_softc *);
435 	uint16_t pcv_chipid;
436 } pcn_variants[] = {
437 	{ "Am79c970 PCnet-PCI",
438 	  pcn_79c970_mediainit,
439 	  PARTID_Am79c970 },
440 
441 	{ "Am79c970A PCnet-PCI II",
442 	  pcn_79c970_mediainit,
443 	  PARTID_Am79c970A },
444 
445 	{ "Am79c971 PCnet-FAST",
446 	  pcn_79c971_mediainit,
447 	  PARTID_Am79c971 },
448 
449 	{ "Am79c972 PCnet-FAST+",
450 	  pcn_79c971_mediainit,
451 	  PARTID_Am79c972 },
452 
453 	{ "Am79c973 PCnet-FAST III",
454 	  pcn_79c971_mediainit,
455 	  PARTID_Am79c973 },
456 
457 	{ "Am79c975 PCnet-FAST III",
458 	  pcn_79c971_mediainit,
459 	  PARTID_Am79c975 },
460 
461 	{ "Unknown PCnet-PCI variant",
462 	  pcn_79c971_mediainit,
463 	  0 },
464 };
465 
466 int	pcn_copy_small = 0;
467 
468 static int	pcn_match(struct device *, struct cfdata *, void *);
469 static void	pcn_attach(struct device *, struct device *, void *);
470 
471 CFATTACH_DECL(pcn, sizeof(struct pcn_softc),
472     pcn_match, pcn_attach, NULL, NULL);
473 
474 /*
475  * Routines to read and write the PCnet-PCI CSR/BCR space.
476  */
477 
478 static inline uint32_t
479 pcn_csr_read(struct pcn_softc *sc, int reg)
480 {
481 
482 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
483 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_RDP));
484 }
485 
486 static inline void
487 pcn_csr_write(struct pcn_softc *sc, int reg, uint32_t val)
488 {
489 
490 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
491 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RDP, val);
492 }
493 
494 static inline uint32_t
495 pcn_bcr_read(struct pcn_softc *sc, int reg)
496 {
497 
498 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
499 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_BDP));
500 }
501 
502 static inline void
503 pcn_bcr_write(struct pcn_softc *sc, int reg, uint32_t val)
504 {
505 
506 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
507 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_BDP, val);
508 }
509 
510 static bool
511 pcn_is_vmware(const char *enaddr)
512 {
513 
514 	/*
515 	 * VMware uses the OUI 00:0c:29 for auto-generated MAC
516 	 * addresses.
517 	 */
518 	if (enaddr[0] == 0x00 && enaddr[1] == 0x0c && enaddr[2] == 0x29)
519 		return (TRUE);
520 
521 	/*
522 	 * VMware uses the OUI 00:50:56 for manually-set MAC
523 	 * addresses (and some auto-generated ones).
524 	 */
525 	if (enaddr[0] == 0x00 && enaddr[1] == 0x50 && enaddr[2] == 0x56)
526 		return (TRUE);
527 
528 	return (FALSE);
529 }
530 
531 static const struct pcn_variant *
532 pcn_lookup_variant(uint16_t chipid)
533 {
534 	const struct pcn_variant *pcv;
535 
536 	for (pcv = pcn_variants; pcv->pcv_chipid != 0; pcv++) {
537 		if (chipid == pcv->pcv_chipid)
538 			return (pcv);
539 	}
540 
541 	/*
542 	 * This covers unknown chips, which we simply treat like
543 	 * a generic PCnet-FAST.
544 	 */
545 	return (pcv);
546 }
547 
548 static int
549 pcn_match(struct device *parent, struct cfdata *cf, void *aux)
550 {
551 	struct pci_attach_args *pa = aux;
552 
553 	/*
554 	 * IBM Makes a PCI variant of this card which shows up as a
555 	 * Trident Microsystems 4DWAVE DX (ethernet network, revision 0x25)
556 	 * this card is truly a pcn card, so we have a special case match for
557 	 * it
558 	 */
559 
560 	if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_TRIDENT &&
561 	    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_TRIDENT_4DWAVE_DX &&
562 	    PCI_CLASS(pa->pa_class) == PCI_CLASS_NETWORK)
563 		return(1);
564 
565 	if (PCI_VENDOR(pa->pa_id) != PCI_VENDOR_AMD)
566 		return (0);
567 
568 	switch (PCI_PRODUCT(pa->pa_id)) {
569 	case PCI_PRODUCT_AMD_PCNET_PCI:
570 		/* Beat if_le_pci.c */
571 		return (10);
572 	}
573 
574 	return (0);
575 }
576 
577 static void
578 pcn_attach(struct device *parent, struct device *self, void *aux)
579 {
580 	struct pcn_softc *sc = (struct pcn_softc *) self;
581 	struct pci_attach_args *pa = aux;
582 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
583 	pci_chipset_tag_t pc = pa->pa_pc;
584 	pci_intr_handle_t ih;
585 	const char *intrstr = NULL;
586 	bus_space_tag_t iot, memt;
587 	bus_space_handle_t ioh, memh;
588 	bus_dma_segment_t seg;
589 	int ioh_valid, memh_valid;
590 	int ntxsegs, i, rseg, error;
591 	uint32_t chipid, reg;
592 	uint8_t enaddr[ETHER_ADDR_LEN];
593 	prop_object_t obj;
594 	bool is_vmware;
595 
596 	callout_init(&sc->sc_tick_ch, 0);
597 
598 	printf(": AMD PCnet-PCI Ethernet\n");
599 
600 	/*
601 	 * Map the device.
602 	 */
603 	ioh_valid = (pci_mapreg_map(pa, PCN_PCI_CBIO, PCI_MAPREG_TYPE_IO, 0,
604 	    &iot, &ioh, NULL, NULL) == 0);
605 	memh_valid = (pci_mapreg_map(pa, PCN_PCI_CBMEM,
606 	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
607 	    &memt, &memh, NULL, NULL) == 0);
608 
609 	if (memh_valid) {
610 		sc->sc_st = memt;
611 		sc->sc_sh = memh;
612 	} else if (ioh_valid) {
613 		sc->sc_st = iot;
614 		sc->sc_sh = ioh;
615 	} else {
616 		printf("%s: unable to map device registers\n",
617 		    sc->sc_dev.dv_xname);
618 		return;
619 	}
620 
621 	sc->sc_dmat = pa->pa_dmat;
622 
623 	/* Make sure bus mastering is enabled. */
624 	pci_conf_write(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
625 	    pci_conf_read(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG) |
626 	    PCI_COMMAND_MASTER_ENABLE);
627 
628 	/* power up chip */
629 	if ((error = pci_activate(pa->pa_pc, pa->pa_tag, sc,
630 	    NULL)) && error != EOPNOTSUPP) {
631 		aprint_error("%s: cannot activate %d\n", sc->sc_dev.dv_xname,
632 		    error);
633 		return;
634 	}
635 
636 	/*
637 	 * Reset the chip to a known state.  This also puts the
638 	 * chip into 32-bit mode.
639 	 */
640 	pcn_reset(sc);
641 
642 	/*
643 	 * On some systems with the chip is an on-board device, the
644 	 * EEPROM is not used.  Handle this by reading the MAC address
645 	 * from the CSRs (assuming that boot firmware has written
646 	 * it there).
647 	 */
648 	obj = prop_dictionary_get(device_properties(&sc->sc_dev),
649 				  "am79c970-no-eeprom");
650 	if (prop_bool_true(obj)) {
651 	        for (i = 0; i < 3; i++) {
652 			uint32_t val;
653 			val = pcn_csr_read(sc, LE_CSR12 + i);
654 			enaddr[2*i] = val & 0x0ff;
655 			enaddr[2*i+1] = (val >> 8) & 0x0ff;
656 		}
657 	} else {
658 		for (i = 0; i < ETHER_ADDR_LEN; i++) {
659 			enaddr[i] = bus_space_read_1(sc->sc_st, sc->sc_sh,
660 			    PCN32_APROM + i);
661 		}
662 	}
663 
664 	/* Check to see if this is a VMware emulated network interface. */
665 	is_vmware = pcn_is_vmware(enaddr);
666 
667 	/*
668 	 * Now that the device is mapped, attempt to figure out what
669 	 * kind of chip we have.  Note that IDL has all 32 bits of
670 	 * the chip ID when we're in 32-bit mode.
671 	 */
672 	chipid = pcn_csr_read(sc, LE_CSR88);
673 	sc->sc_variant = pcn_lookup_variant(CHIPID_PARTID(chipid));
674 
675 	printf("%s: %s rev %d, Ethernet address %s\n",
676 	    sc->sc_dev.dv_xname, sc->sc_variant->pcv_desc, CHIPID_VER(chipid),
677 	    ether_sprintf(enaddr));
678 
679 	/*
680 	 * VMware has a bug in its network interface emulation; we must
681 	 * limit the number of Tx segments.
682 	 */
683 	if (is_vmware) {
684 		ntxsegs = PCN_NTXSEGS_VMWARE;
685 		prop_dictionary_set_bool(device_properties(&sc->sc_dev),
686 					 "am79c970-vmware-tx-bug", TRUE);
687 		aprint_verbose("%s: VMware Tx segment count bug detected\n",
688 			       sc->sc_dev.dv_xname);
689 	} else {
690 		ntxsegs = PCN_NTXSEGS;
691 	}
692 
693 	/*
694 	 * Map and establish our interrupt.
695 	 */
696 	if (pci_intr_map(pa, &ih)) {
697 		printf("%s: unable to map interrupt\n", sc->sc_dev.dv_xname);
698 		return;
699 	}
700 	intrstr = pci_intr_string(pc, ih);
701 	sc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, pcn_intr, sc);
702 	if (sc->sc_ih == NULL) {
703 		printf("%s: unable to establish interrupt",
704 		    sc->sc_dev.dv_xname);
705 		if (intrstr != NULL)
706 			printf(" at %s", intrstr);
707 		printf("\n");
708 		return;
709 	}
710 	printf("%s: interrupting at %s\n", sc->sc_dev.dv_xname, intrstr);
711 
712 	/*
713 	 * Allocate the control data structures, and create and load the
714 	 * DMA map for it.
715 	 */
716 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
717 	     sizeof(struct pcn_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
718 	     0)) != 0) {
719 		printf("%s: unable to allocate control data, error = %d\n",
720 		    sc->sc_dev.dv_xname, error);
721 		goto fail_0;
722 	}
723 
724 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
725 	     sizeof(struct pcn_control_data), (void **)&sc->sc_control_data,
726 	     BUS_DMA_COHERENT)) != 0) {
727 		printf("%s: unable to map control data, error = %d\n",
728 		    sc->sc_dev.dv_xname, error);
729 		goto fail_1;
730 	}
731 
732 	if ((error = bus_dmamap_create(sc->sc_dmat,
733 	     sizeof(struct pcn_control_data), 1,
734 	     sizeof(struct pcn_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
735 		printf("%s: unable to create control data DMA map, "
736 		    "error = %d\n", sc->sc_dev.dv_xname, error);
737 		goto fail_2;
738 	}
739 
740 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
741 	     sc->sc_control_data, sizeof(struct pcn_control_data), NULL,
742 	     0)) != 0) {
743 		printf("%s: unable to load control data DMA map, error = %d\n",
744 		    sc->sc_dev.dv_xname, error);
745 		goto fail_3;
746 	}
747 
748 	/* Create the transmit buffer DMA maps. */
749 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
750 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
751 		     ntxsegs, MCLBYTES, 0, 0,
752 		     &sc->sc_txsoft[i].txs_dmamap)) != 0) {
753 			printf("%s: unable to create tx DMA map %d, "
754 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
755 			goto fail_4;
756 		}
757 	}
758 
759 	/* Create the receive buffer DMA maps. */
760 	for (i = 0; i < PCN_NRXDESC; i++) {
761 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
762 		     MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
763 			printf("%s: unable to create rx DMA map %d, "
764 			    "error = %d\n", sc->sc_dev.dv_xname, i, error);
765 			goto fail_5;
766 		}
767 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
768 	}
769 
770 	/* Initialize our media structures. */
771 	(*sc->sc_variant->pcv_mediainit)(sc);
772 
773 	/*
774 	 * Initialize FIFO watermark info.
775 	 */
776 	switch (sc->sc_variant->pcv_chipid) {
777 	case PARTID_Am79c970:
778 	case PARTID_Am79c970A:
779 		sc->sc_rcvfw_desc = pcn_79c970_rcvfw;
780 		sc->sc_xmtsp_desc = pcn_79c970_xmtsp;
781 		sc->sc_xmtfw_desc = pcn_79c970_xmtfw;
782 		break;
783 
784 	default:
785 		sc->sc_rcvfw_desc = pcn_79c971_rcvfw;
786 		/*
787 		 * Read BCR25 to determine how much SRAM is
788 		 * on the board.  If > 0, then we the chip
789 		 * uses different Start Point thresholds.
790 		 *
791 		 * Note BCR25 and BCR26 are loaded from the
792 		 * EEPROM on RST, and unaffected by S_RESET,
793 		 * so we don't really have to worry about
794 		 * them except for this.
795 		 */
796 		reg = pcn_bcr_read(sc, LE_BCR25) & 0x00ff;
797 		if (reg != 0)
798 			sc->sc_xmtsp_desc = pcn_79c971_xmtsp_sram;
799 		else
800 			sc->sc_xmtsp_desc = pcn_79c971_xmtsp;
801 		sc->sc_xmtfw_desc = pcn_79c971_xmtfw;
802 		break;
803 	}
804 
805 	/*
806 	 * Set up defaults -- see the tables above for what these
807 	 * values mean.
808 	 *
809 	 * XXX How should we tune RCVFW and XMTFW?
810 	 */
811 	sc->sc_rcvfw = 1;	/* minimum for full-duplex */
812 	sc->sc_xmtsp = 1;
813 	sc->sc_xmtfw = 0;
814 
815 	ifp = &sc->sc_ethercom.ec_if;
816 	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
817 	ifp->if_softc = sc;
818 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
819 	ifp->if_ioctl = pcn_ioctl;
820 	ifp->if_start = pcn_start;
821 	ifp->if_watchdog = pcn_watchdog;
822 	ifp->if_init = pcn_init;
823 	ifp->if_stop = pcn_stop;
824 	IFQ_SET_READY(&ifp->if_snd);
825 
826 	/* Attach the interface. */
827 	if_attach(ifp);
828 	ether_ifattach(ifp, enaddr);
829 #if NRND > 0
830 	rnd_attach_source(&sc->rnd_source, sc->sc_dev.dv_xname,
831 	    RND_TYPE_NET, 0);
832 #endif
833 
834 #ifdef PCN_EVENT_COUNTERS
835 	/* Attach event counters. */
836 	evcnt_attach_dynamic(&sc->sc_ev_txsstall, EVCNT_TYPE_MISC,
837 	    NULL, sc->sc_dev.dv_xname, "txsstall");
838 	evcnt_attach_dynamic(&sc->sc_ev_txdstall, EVCNT_TYPE_MISC,
839 	    NULL, sc->sc_dev.dv_xname, "txdstall");
840 	evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_INTR,
841 	    NULL, sc->sc_dev.dv_xname, "txintr");
842 	evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_INTR,
843 	    NULL, sc->sc_dev.dv_xname, "rxintr");
844 	evcnt_attach_dynamic(&sc->sc_ev_babl, EVCNT_TYPE_MISC,
845 	    NULL, sc->sc_dev.dv_xname, "babl");
846 	evcnt_attach_dynamic(&sc->sc_ev_miss, EVCNT_TYPE_MISC,
847 	    NULL, sc->sc_dev.dv_xname, "miss");
848 	evcnt_attach_dynamic(&sc->sc_ev_merr, EVCNT_TYPE_MISC,
849 	    NULL, sc->sc_dev.dv_xname, "merr");
850 
851 	evcnt_attach_dynamic(&sc->sc_ev_txseg1, EVCNT_TYPE_MISC,
852 	    NULL, sc->sc_dev.dv_xname, "txseg1");
853 	evcnt_attach_dynamic(&sc->sc_ev_txseg2, EVCNT_TYPE_MISC,
854 	    NULL, sc->sc_dev.dv_xname, "txseg2");
855 	evcnt_attach_dynamic(&sc->sc_ev_txseg3, EVCNT_TYPE_MISC,
856 	    NULL, sc->sc_dev.dv_xname, "txseg3");
857 	evcnt_attach_dynamic(&sc->sc_ev_txseg4, EVCNT_TYPE_MISC,
858 	    NULL, sc->sc_dev.dv_xname, "txseg4");
859 	evcnt_attach_dynamic(&sc->sc_ev_txseg5, EVCNT_TYPE_MISC,
860 	    NULL, sc->sc_dev.dv_xname, "txseg5");
861 	evcnt_attach_dynamic(&sc->sc_ev_txsegmore, EVCNT_TYPE_MISC,
862 	    NULL, sc->sc_dev.dv_xname, "txsegmore");
863 	evcnt_attach_dynamic(&sc->sc_ev_txcopy, EVCNT_TYPE_MISC,
864 	    NULL, sc->sc_dev.dv_xname, "txcopy");
865 #endif /* PCN_EVENT_COUNTERS */
866 
867 	/* Make sure the interface is shutdown during reboot. */
868 	sc->sc_sdhook = shutdownhook_establish(pcn_shutdown, sc);
869 	if (sc->sc_sdhook == NULL)
870 		printf("%s: WARNING: unable to establish shutdown hook\n",
871 		    sc->sc_dev.dv_xname);
872 	return;
873 
874 	/*
875 	 * Free any resources we've allocated during the failed attach
876 	 * attempt.  Do this in reverse order and fall through.
877 	 */
878  fail_5:
879 	for (i = 0; i < PCN_NRXDESC; i++) {
880 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
881 			bus_dmamap_destroy(sc->sc_dmat,
882 			    sc->sc_rxsoft[i].rxs_dmamap);
883 	}
884  fail_4:
885 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
886 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
887 			bus_dmamap_destroy(sc->sc_dmat,
888 			    sc->sc_txsoft[i].txs_dmamap);
889 	}
890 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
891  fail_3:
892 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
893  fail_2:
894 	bus_dmamem_unmap(sc->sc_dmat, (void *)sc->sc_control_data,
895 	    sizeof(struct pcn_control_data));
896  fail_1:
897 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
898  fail_0:
899 	return;
900 }
901 
902 /*
903  * pcn_shutdown:
904  *
905  *	Make sure the interface is stopped at reboot time.
906  */
907 static void
908 pcn_shutdown(void *arg)
909 {
910 	struct pcn_softc *sc = arg;
911 
912 	pcn_stop(&sc->sc_ethercom.ec_if, 1);
913 	/* explicitly reset the chip for some onboard one with lazy firmware */
914 	pcn_reset(sc);
915 }
916 
917 /*
918  * pcn_start:		[ifnet interface function]
919  *
920  *	Start packet transmission on the interface.
921  */
922 static void
923 pcn_start(struct ifnet *ifp)
924 {
925 	struct pcn_softc *sc = ifp->if_softc;
926 	struct mbuf *m0, *m;
927 	struct pcn_txsoft *txs;
928 	bus_dmamap_t dmamap;
929 	int error, nexttx, lasttx = -1, ofree, seg;
930 
931 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
932 		return;
933 
934 	/*
935 	 * Remember the previous number of free descriptors and
936 	 * the first descriptor we'll use.
937 	 */
938 	ofree = sc->sc_txfree;
939 
940 	/*
941 	 * Loop through the send queue, setting up transmit descriptors
942 	 * until we drain the queue, or use up all available transmit
943 	 * descriptors.
944 	 */
945 	for (;;) {
946 		/* Grab a packet off the queue. */
947 		IFQ_POLL(&ifp->if_snd, m0);
948 		if (m0 == NULL)
949 			break;
950 		m = NULL;
951 
952 		/* Get a work queue entry. */
953 		if (sc->sc_txsfree == 0) {
954 			PCN_EVCNT_INCR(&sc->sc_ev_txsstall);
955 			break;
956 		}
957 
958 		txs = &sc->sc_txsoft[sc->sc_txsnext];
959 		dmamap = txs->txs_dmamap;
960 
961 		/*
962 		 * Load the DMA map.  If this fails, the packet either
963 		 * didn't fit in the alloted number of segments, or we
964 		 * were short on resources.  In this case, we'll copy
965 		 * and try again.
966 		 */
967 		if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
968 		    BUS_DMA_WRITE|BUS_DMA_NOWAIT) != 0) {
969 			PCN_EVCNT_INCR(&sc->sc_ev_txcopy);
970 			MGETHDR(m, M_DONTWAIT, MT_DATA);
971 			if (m == NULL) {
972 				printf("%s: unable to allocate Tx mbuf\n",
973 				    sc->sc_dev.dv_xname);
974 				break;
975 			}
976 			if (m0->m_pkthdr.len > MHLEN) {
977 				MCLGET(m, M_DONTWAIT);
978 				if ((m->m_flags & M_EXT) == 0) {
979 					printf("%s: unable to allocate Tx "
980 					    "cluster\n", sc->sc_dev.dv_xname);
981 					m_freem(m);
982 					break;
983 				}
984 			}
985 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, void *));
986 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
987 			error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
988 			    m, BUS_DMA_WRITE|BUS_DMA_NOWAIT);
989 			if (error) {
990 				printf("%s: unable to load Tx buffer, "
991 				    "error = %d\n", sc->sc_dev.dv_xname, error);
992 				break;
993 			}
994 		}
995 
996 		/*
997 		 * Ensure we have enough descriptors free to describe
998 		 * the packet.  Note, we always reserve one descriptor
999 		 * at the end of the ring as a termination point, to
1000 		 * prevent wrap-around.
1001 		 */
1002 		if (dmamap->dm_nsegs > (sc->sc_txfree - 1)) {
1003 			/*
1004 			 * Not enough free descriptors to transmit this
1005 			 * packet.  We haven't committed anything yet,
1006 			 * so just unload the DMA map, put the packet
1007 			 * back on the queue, and punt.  Notify the upper
1008 			 * layer that there are not more slots left.
1009 			 *
1010 			 * XXX We could allocate an mbuf and copy, but
1011 			 * XXX is it worth it?
1012 			 */
1013 			ifp->if_flags |= IFF_OACTIVE;
1014 			bus_dmamap_unload(sc->sc_dmat, dmamap);
1015 			if (m != NULL)
1016 				m_freem(m);
1017 			PCN_EVCNT_INCR(&sc->sc_ev_txdstall);
1018 			break;
1019 		}
1020 
1021 		IFQ_DEQUEUE(&ifp->if_snd, m0);
1022 		if (m != NULL) {
1023 			m_freem(m0);
1024 			m0 = m;
1025 		}
1026 
1027 		/*
1028 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
1029 		 */
1030 
1031 		/* Sync the DMA map. */
1032 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
1033 		    BUS_DMASYNC_PREWRITE);
1034 
1035 #ifdef PCN_EVENT_COUNTERS
1036 		switch (dmamap->dm_nsegs) {
1037 		case 1:
1038 			PCN_EVCNT_INCR(&sc->sc_ev_txseg1);
1039 			break;
1040 		case 2:
1041 			PCN_EVCNT_INCR(&sc->sc_ev_txseg2);
1042 			break;
1043 		case 3:
1044 			PCN_EVCNT_INCR(&sc->sc_ev_txseg3);
1045 			break;
1046 		case 4:
1047 			PCN_EVCNT_INCR(&sc->sc_ev_txseg4);
1048 			break;
1049 		case 5:
1050 			PCN_EVCNT_INCR(&sc->sc_ev_txseg5);
1051 			break;
1052 		default:
1053 			PCN_EVCNT_INCR(&sc->sc_ev_txsegmore);
1054 			break;
1055 		}
1056 #endif /* PCN_EVENT_COUNTERS */
1057 
1058 		/*
1059 		 * Initialize the transmit descriptors.
1060 		 */
1061 		if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3) {
1062 			for (nexttx = sc->sc_txnext, seg = 0;
1063 			     seg < dmamap->dm_nsegs;
1064 			     seg++, nexttx = PCN_NEXTTX(nexttx)) {
1065 				/*
1066 				 * If this is the first descriptor we're
1067 				 * enqueueing, don't set the OWN bit just
1068 				 * yet.  That could cause a race condition.
1069 				 * We'll do it below.
1070 				 */
1071 				sc->sc_txdescs[nexttx].tmd0 = 0;
1072 				sc->sc_txdescs[nexttx].tmd2 =
1073 				    htole32(dmamap->dm_segs[seg].ds_addr);
1074 				sc->sc_txdescs[nexttx].tmd1 =
1075 				    htole32(LE_T1_ONES |
1076 				    (nexttx == sc->sc_txnext ? 0 : LE_T1_OWN) |
1077 				    (LE_BCNT(dmamap->dm_segs[seg].ds_len) &
1078 				     LE_T1_BCNT_MASK));
1079 				lasttx = nexttx;
1080 			}
1081 		} else {
1082 			for (nexttx = sc->sc_txnext, seg = 0;
1083 			     seg < dmamap->dm_nsegs;
1084 			     seg++, nexttx = PCN_NEXTTX(nexttx)) {
1085 				/*
1086 				 * If this is the first descriptor we're
1087 				 * enqueueing, don't set the OWN bit just
1088 				 * yet.  That could cause a race condition.
1089 				 * We'll do it below.
1090 				 */
1091 				sc->sc_txdescs[nexttx].tmd0 =
1092 				    htole32(dmamap->dm_segs[seg].ds_addr);
1093 				sc->sc_txdescs[nexttx].tmd2 = 0;
1094 				sc->sc_txdescs[nexttx].tmd1 =
1095 				    htole32(LE_T1_ONES |
1096 				    (nexttx == sc->sc_txnext ? 0 : LE_T1_OWN) |
1097 				    (LE_BCNT(dmamap->dm_segs[seg].ds_len) &
1098 				     LE_T1_BCNT_MASK));
1099 				lasttx = nexttx;
1100 			}
1101 		}
1102 
1103 		KASSERT(lasttx != -1);
1104 		/* Interrupt on the packet, if appropriate. */
1105 		if ((sc->sc_txsnext & PCN_TXINTR_MASK) == 0)
1106 			sc->sc_txdescs[lasttx].tmd1 |= htole32(LE_T1_LTINT);
1107 
1108 		/* Set `start of packet' and `end of packet' appropriately. */
1109 		sc->sc_txdescs[lasttx].tmd1 |= htole32(LE_T1_ENP);
1110 		sc->sc_txdescs[sc->sc_txnext].tmd1 |=
1111 		    htole32(LE_T1_OWN|LE_T1_STP);
1112 
1113 		/* Sync the descriptors we're using. */
1114 		PCN_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
1115 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1116 
1117 		/* Kick the transmitter. */
1118 		pcn_csr_write(sc, LE_CSR0, LE_C0_INEA|LE_C0_TDMD);
1119 
1120 		/*
1121 		 * Store a pointer to the packet so we can free it later,
1122 		 * and remember what txdirty will be once the packet is
1123 		 * done.
1124 		 */
1125 		txs->txs_mbuf = m0;
1126 		txs->txs_firstdesc = sc->sc_txnext;
1127 		txs->txs_lastdesc = lasttx;
1128 
1129 		/* Advance the tx pointer. */
1130 		sc->sc_txfree -= dmamap->dm_nsegs;
1131 		sc->sc_txnext = nexttx;
1132 
1133 		sc->sc_txsfree--;
1134 		sc->sc_txsnext = PCN_NEXTTXS(sc->sc_txsnext);
1135 
1136 #if NBPFILTER > 0
1137 		/* Pass the packet to any BPF listeners. */
1138 		if (ifp->if_bpf)
1139 			bpf_mtap(ifp->if_bpf, m0);
1140 #endif /* NBPFILTER > 0 */
1141 	}
1142 
1143 	if (sc->sc_txsfree == 0 || sc->sc_txfree == 0) {
1144 		/* No more slots left; notify upper layer. */
1145 		ifp->if_flags |= IFF_OACTIVE;
1146 	}
1147 
1148 	if (sc->sc_txfree != ofree) {
1149 		/* Set a watchdog timer in case the chip flakes out. */
1150 		ifp->if_timer = 5;
1151 	}
1152 }
1153 
1154 /*
1155  * pcn_watchdog:	[ifnet interface function]
1156  *
1157  *	Watchdog timer handler.
1158  */
1159 static void
1160 pcn_watchdog(struct ifnet *ifp)
1161 {
1162 	struct pcn_softc *sc = ifp->if_softc;
1163 
1164 	/*
1165 	 * Since we're not interrupting every packet, sweep
1166 	 * up before we report an error.
1167 	 */
1168 	pcn_txintr(sc);
1169 
1170 	if (sc->sc_txfree != PCN_NTXDESC) {
1171 		printf("%s: device timeout (txfree %d txsfree %d)\n",
1172 		    sc->sc_dev.dv_xname, sc->sc_txfree, sc->sc_txsfree);
1173 		ifp->if_oerrors++;
1174 
1175 		/* Reset the interface. */
1176 		(void) pcn_init(ifp);
1177 	}
1178 
1179 	/* Try to get more packets going. */
1180 	pcn_start(ifp);
1181 }
1182 
1183 /*
1184  * pcn_ioctl:		[ifnet interface function]
1185  *
1186  *	Handle control requests from the operator.
1187  */
1188 static int
1189 pcn_ioctl(struct ifnet *ifp, u_long cmd, void *data)
1190 {
1191 	struct pcn_softc *sc = ifp->if_softc;
1192 	struct ifreq *ifr = (struct ifreq *) data;
1193 	int s, error;
1194 
1195 	s = splnet();
1196 
1197 	switch (cmd) {
1198 	case SIOCSIFMEDIA:
1199 	case SIOCGIFMEDIA:
1200 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
1201 		break;
1202 
1203 	default:
1204 		error = ether_ioctl(ifp, cmd, data);
1205 		if (error == ENETRESET) {
1206 			/*
1207 			 * Multicast list has changed; set the hardware filter
1208 			 * accordingly.
1209 			 */
1210 			if (ifp->if_flags & IFF_RUNNING)
1211 				error = pcn_init(ifp);
1212 			else
1213 				error = 0;
1214 		}
1215 		break;
1216 	}
1217 
1218 	/* Try to get more packets going. */
1219 	pcn_start(ifp);
1220 
1221 	splx(s);
1222 	return (error);
1223 }
1224 
1225 /*
1226  * pcn_intr:
1227  *
1228  *	Interrupt service routine.
1229  */
1230 static int
1231 pcn_intr(void *arg)
1232 {
1233 	struct pcn_softc *sc = arg;
1234 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1235 	uint32_t csr0;
1236 	int wantinit, handled = 0;
1237 
1238 	for (wantinit = 0; wantinit == 0;) {
1239 		csr0 = pcn_csr_read(sc, LE_CSR0);
1240 		if ((csr0 & LE_C0_INTR) == 0)
1241 			break;
1242 
1243 #if NRND > 0
1244 		if (RND_ENABLED(&sc->rnd_source))
1245 			rnd_add_uint32(&sc->rnd_source, csr0);
1246 #endif
1247 
1248 		/* ACK the bits and re-enable interrupts. */
1249 		pcn_csr_write(sc, LE_CSR0, csr0 &
1250 		    (LE_C0_INEA|LE_C0_BABL|LE_C0_MISS|LE_C0_MERR|LE_C0_RINT|
1251 		     LE_C0_TINT|LE_C0_IDON));
1252 
1253 		handled = 1;
1254 
1255 		if (csr0 & LE_C0_RINT) {
1256 			PCN_EVCNT_INCR(&sc->sc_ev_rxintr);
1257 			wantinit = pcn_rxintr(sc);
1258 		}
1259 
1260 		if (csr0 & LE_C0_TINT) {
1261 			PCN_EVCNT_INCR(&sc->sc_ev_txintr);
1262 			pcn_txintr(sc);
1263 		}
1264 
1265 		if (csr0 & LE_C0_ERR) {
1266 			if (csr0 & LE_C0_BABL) {
1267 				PCN_EVCNT_INCR(&sc->sc_ev_babl);
1268 				ifp->if_oerrors++;
1269 			}
1270 			if (csr0 & LE_C0_MISS) {
1271 				PCN_EVCNT_INCR(&sc->sc_ev_miss);
1272 				ifp->if_ierrors++;
1273 			}
1274 			if (csr0 & LE_C0_MERR) {
1275 				PCN_EVCNT_INCR(&sc->sc_ev_merr);
1276 				printf("%s: memory error\n",
1277 				    sc->sc_dev.dv_xname);
1278 				wantinit = 1;
1279 				break;
1280 			}
1281 		}
1282 
1283 		if ((csr0 & LE_C0_RXON) == 0) {
1284 			printf("%s: receiver disabled\n",
1285 			    sc->sc_dev.dv_xname);
1286 			ifp->if_ierrors++;
1287 			wantinit = 1;
1288 		}
1289 
1290 		if ((csr0 & LE_C0_TXON) == 0) {
1291 			printf("%s: transmitter disabled\n",
1292 			    sc->sc_dev.dv_xname);
1293 			ifp->if_oerrors++;
1294 			wantinit = 1;
1295 		}
1296 	}
1297 
1298 	if (handled) {
1299 		if (wantinit)
1300 			pcn_init(ifp);
1301 
1302 		/* Try to get more packets going. */
1303 		pcn_start(ifp);
1304 	}
1305 
1306 	return (handled);
1307 }
1308 
1309 /*
1310  * pcn_spnd:
1311  *
1312  *	Suspend the chip.
1313  */
1314 static void
1315 pcn_spnd(struct pcn_softc *sc)
1316 {
1317 	int i;
1318 
1319 	pcn_csr_write(sc, LE_CSR5, sc->sc_csr5 | LE_C5_SPND);
1320 
1321 	for (i = 0; i < 10000; i++) {
1322 		if (pcn_csr_read(sc, LE_CSR5) & LE_C5_SPND)
1323 			return;
1324 		delay(5);
1325 	}
1326 
1327 	printf("%s: WARNING: chip failed to enter suspended state\n",
1328 	    sc->sc_dev.dv_xname);
1329 }
1330 
1331 /*
1332  * pcn_txintr:
1333  *
1334  *	Helper; handle transmit interrupts.
1335  */
1336 static void
1337 pcn_txintr(struct pcn_softc *sc)
1338 {
1339 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1340 	struct pcn_txsoft *txs;
1341 	uint32_t tmd1, tmd2, tmd;
1342 	int i, j;
1343 
1344 	ifp->if_flags &= ~IFF_OACTIVE;
1345 
1346 	/*
1347 	 * Go through our Tx list and free mbufs for those
1348 	 * frames which have been transmitted.
1349 	 */
1350 	for (i = sc->sc_txsdirty; sc->sc_txsfree != PCN_TXQUEUELEN;
1351 	     i = PCN_NEXTTXS(i), sc->sc_txsfree++) {
1352 		txs = &sc->sc_txsoft[i];
1353 
1354 		PCN_CDTXSYNC(sc, txs->txs_firstdesc, txs->txs_dmamap->dm_nsegs,
1355 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1356 
1357 		tmd1 = le32toh(sc->sc_txdescs[txs->txs_lastdesc].tmd1);
1358 		if (tmd1 & LE_T1_OWN)
1359 			break;
1360 
1361 		/*
1362 		 * Slightly annoying -- we have to loop through the
1363 		 * descriptors we've used looking for ERR, since it
1364 		 * can appear on any descriptor in the chain.
1365 		 */
1366 		for (j = txs->txs_firstdesc;; j = PCN_NEXTTX(j)) {
1367 			tmd = le32toh(sc->sc_txdescs[j].tmd1);
1368 			if (tmd & LE_T1_ERR) {
1369 				ifp->if_oerrors++;
1370 				if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3)
1371 					tmd2 = le32toh(sc->sc_txdescs[j].tmd0);
1372 				else
1373 					tmd2 = le32toh(sc->sc_txdescs[j].tmd2);
1374 				if (tmd2 & LE_T2_UFLO) {
1375 					if (sc->sc_xmtsp < LE_C80_XMTSP_MAX) {
1376 						sc->sc_xmtsp++;
1377 						printf("%s: transmit "
1378 						    "underrun; new threshold: "
1379 						    "%s\n",
1380 						    sc->sc_dev.dv_xname,
1381 						    sc->sc_xmtsp_desc[
1382 						    sc->sc_xmtsp]);
1383 						pcn_spnd(sc);
1384 						pcn_csr_write(sc, LE_CSR80,
1385 						    LE_C80_RCVFW(sc->sc_rcvfw) |
1386 						    LE_C80_XMTSP(sc->sc_xmtsp) |
1387 						    LE_C80_XMTFW(sc->sc_xmtfw));
1388 						pcn_csr_write(sc, LE_CSR5,
1389 						    sc->sc_csr5);
1390 					} else {
1391 						printf("%s: transmit "
1392 						    "underrun\n",
1393 						    sc->sc_dev.dv_xname);
1394 					}
1395 				} else if (tmd2 & LE_T2_BUFF) {
1396 					printf("%s: transmit buffer error\n",
1397 					    sc->sc_dev.dv_xname);
1398 				}
1399 				if (tmd2 & LE_T2_LCOL)
1400 					ifp->if_collisions++;
1401 				if (tmd2 & LE_T2_RTRY)
1402 					ifp->if_collisions += 16;
1403 				goto next_packet;
1404 			}
1405 			if (j == txs->txs_lastdesc)
1406 				break;
1407 		}
1408 		if (tmd1 & LE_T1_ONE)
1409 			ifp->if_collisions++;
1410 		else if (tmd & LE_T1_MORE) {
1411 			/* Real number is unknown. */
1412 			ifp->if_collisions += 2;
1413 		}
1414 		ifp->if_opackets++;
1415  next_packet:
1416 		sc->sc_txfree += txs->txs_dmamap->dm_nsegs;
1417 		bus_dmamap_sync(sc->sc_dmat, txs->txs_dmamap,
1418 		    0, txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
1419 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1420 		m_freem(txs->txs_mbuf);
1421 		txs->txs_mbuf = NULL;
1422 	}
1423 
1424 	/* Update the dirty transmit buffer pointer. */
1425 	sc->sc_txsdirty = i;
1426 
1427 	/*
1428 	 * If there are no more pending transmissions, cancel the watchdog
1429 	 * timer.
1430 	 */
1431 	if (sc->sc_txsfree == PCN_TXQUEUELEN)
1432 		ifp->if_timer = 0;
1433 }
1434 
1435 /*
1436  * pcn_rxintr:
1437  *
1438  *	Helper; handle receive interrupts.
1439  */
1440 static int
1441 pcn_rxintr(struct pcn_softc *sc)
1442 {
1443 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1444 	struct pcn_rxsoft *rxs;
1445 	struct mbuf *m;
1446 	uint32_t rmd1;
1447 	int i, len;
1448 
1449 	for (i = sc->sc_rxptr;; i = PCN_NEXTRX(i)) {
1450 		rxs = &sc->sc_rxsoft[i];
1451 
1452 		PCN_CDRXSYNC(sc, i, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1453 
1454 		rmd1 = le32toh(sc->sc_rxdescs[i].rmd1);
1455 
1456 		if (rmd1 & LE_R1_OWN)
1457 			break;
1458 
1459 		/*
1460 		 * Check for errors and make sure the packet fit into
1461 		 * a single buffer.  We have structured this block of
1462 		 * code the way it is in order to compress it into
1463 		 * one test in the common case (no error).
1464 		 */
1465 		if (__predict_false((rmd1 & (LE_R1_STP|LE_R1_ENP|LE_R1_ERR)) !=
1466 		    (LE_R1_STP|LE_R1_ENP))) {
1467 			/* Make sure the packet is in a single buffer. */
1468 			if ((rmd1 & (LE_R1_STP|LE_R1_ENP)) !=
1469 			    (LE_R1_STP|LE_R1_ENP)) {
1470 				printf("%s: packet spilled into next buffer\n",
1471 				    sc->sc_dev.dv_xname);
1472 				return (1);	/* pcn_intr() will re-init */
1473 			}
1474 
1475 			/*
1476 			 * If the packet had an error, simple recycle the
1477 			 * buffer.
1478 			 */
1479 			if (rmd1 & LE_R1_ERR) {
1480 				ifp->if_ierrors++;
1481 				/*
1482 				 * If we got an overflow error, chances
1483 				 * are there will be a CRC error.  In
1484 				 * this case, just print the overflow
1485 				 * error, and skip the others.
1486 				 */
1487 				if (rmd1 & LE_R1_OFLO)
1488 					printf("%s: overflow error\n",
1489 					    sc->sc_dev.dv_xname);
1490 				else {
1491 #define	PRINTIT(x, str)							\
1492 					if (rmd1 & (x))			\
1493 						printf("%s: %s\n",	\
1494 						    sc->sc_dev.dv_xname, str);
1495 					PRINTIT(LE_R1_FRAM, "framing error");
1496 					PRINTIT(LE_R1_CRC, "CRC error");
1497 					PRINTIT(LE_R1_BUFF, "buffer error");
1498 				}
1499 #undef PRINTIT
1500 				PCN_INIT_RXDESC(sc, i);
1501 				continue;
1502 			}
1503 		}
1504 
1505 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1506 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1507 
1508 		/*
1509 		 * No errors; receive the packet.
1510 		 */
1511 		if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3)
1512 			len = le32toh(sc->sc_rxdescs[i].rmd0) & LE_R1_BCNT_MASK;
1513 		else
1514 			len = le32toh(sc->sc_rxdescs[i].rmd2) & LE_R1_BCNT_MASK;
1515 
1516 		/*
1517 		 * The LANCE family includes the CRC with every packet;
1518 		 * trim it off here.
1519 		 */
1520 		len -= ETHER_CRC_LEN;
1521 
1522 		/*
1523 		 * If the packet is small enough to fit in a
1524 		 * single header mbuf, allocate one and copy
1525 		 * the data into it.  This greatly reduces
1526 		 * memory consumption when we receive lots
1527 		 * of small packets.
1528 		 *
1529 		 * Otherwise, we add a new buffer to the receive
1530 		 * chain.  If this fails, we drop the packet and
1531 		 * recycle the old buffer.
1532 		 */
1533 		if (pcn_copy_small != 0 && len <= (MHLEN - 2)) {
1534 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1535 			if (m == NULL)
1536 				goto dropit;
1537 			m->m_data += 2;
1538 			memcpy(mtod(m, void *),
1539 			    mtod(rxs->rxs_mbuf, void *), len);
1540 			PCN_INIT_RXDESC(sc, i);
1541 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1542 			    rxs->rxs_dmamap->dm_mapsize,
1543 			    BUS_DMASYNC_PREREAD);
1544 		} else {
1545 			m = rxs->rxs_mbuf;
1546 			if (pcn_add_rxbuf(sc, i) != 0) {
1547  dropit:
1548 				ifp->if_ierrors++;
1549 				PCN_INIT_RXDESC(sc, i);
1550 				bus_dmamap_sync(sc->sc_dmat,
1551 				    rxs->rxs_dmamap, 0,
1552 				    rxs->rxs_dmamap->dm_mapsize,
1553 				    BUS_DMASYNC_PREREAD);
1554 				continue;
1555 			}
1556 		}
1557 
1558 		m->m_pkthdr.rcvif = ifp;
1559 		m->m_pkthdr.len = m->m_len = len;
1560 
1561 #if NBPFILTER > 0
1562 		/* Pass this up to any BPF listeners. */
1563 		if (ifp->if_bpf)
1564 			bpf_mtap(ifp->if_bpf, m);
1565 #endif /* NBPFILTER > 0 */
1566 
1567 		/* Pass it on. */
1568 		(*ifp->if_input)(ifp, m);
1569 		ifp->if_ipackets++;
1570 	}
1571 
1572 	/* Update the receive pointer. */
1573 	sc->sc_rxptr = i;
1574 	return (0);
1575 }
1576 
1577 /*
1578  * pcn_tick:
1579  *
1580  *	One second timer, used to tick the MII.
1581  */
1582 static void
1583 pcn_tick(void *arg)
1584 {
1585 	struct pcn_softc *sc = arg;
1586 	int s;
1587 
1588 	s = splnet();
1589 	mii_tick(&sc->sc_mii);
1590 	splx(s);
1591 
1592 	callout_reset(&sc->sc_tick_ch, hz, pcn_tick, sc);
1593 }
1594 
1595 /*
1596  * pcn_reset:
1597  *
1598  *	Perform a soft reset on the PCnet-PCI.
1599  */
1600 static void
1601 pcn_reset(struct pcn_softc *sc)
1602 {
1603 
1604 	/*
1605 	 * The PCnet-PCI chip is reset by reading from the
1606 	 * RESET register.  Note that while the NE2100 LANCE
1607 	 * boards require a write after the read, the PCnet-PCI
1608 	 * chips do not require this.
1609 	 *
1610 	 * Since we don't know if we're in 16-bit or 32-bit
1611 	 * mode right now, issue both (it's safe) in the
1612 	 * hopes that one will succeed.
1613 	 */
1614 	(void) bus_space_read_2(sc->sc_st, sc->sc_sh, PCN16_RESET);
1615 	(void) bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_RESET);
1616 
1617 	/* Wait 1ms for it to finish. */
1618 	delay(1000);
1619 
1620 	/*
1621 	 * Select 32-bit I/O mode by issuing a 32-bit write to the
1622 	 * RDP.  Since the RAP is 0 after a reset, writing a 0
1623 	 * to RDP is safe (since it simply clears CSR0).
1624 	 */
1625 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RDP, 0);
1626 }
1627 
1628 /*
1629  * pcn_init:		[ifnet interface function]
1630  *
1631  *	Initialize the interface.  Must be called at splnet().
1632  */
1633 static int
1634 pcn_init(struct ifnet *ifp)
1635 {
1636 	struct pcn_softc *sc = ifp->if_softc;
1637 	struct pcn_rxsoft *rxs;
1638 	const uint8_t *enaddr = CLLADDR(ifp->if_sadl);
1639 	int i, error = 0;
1640 	uint32_t reg;
1641 
1642 	/* Cancel any pending I/O. */
1643 	pcn_stop(ifp, 0);
1644 
1645 	/* Reset the chip to a known state. */
1646 	pcn_reset(sc);
1647 
1648 	/*
1649 	 * On the Am79c970, select SSTYLE 2, and SSTYLE 3 on everything
1650 	 * else.
1651 	 *
1652 	 * XXX It'd be really nice to use SSTYLE 2 on all the chips,
1653 	 * because the structure layout is compatible with ILACC,
1654 	 * but the burst mode is only available in SSTYLE 3, and
1655 	 * burst mode should provide some performance enhancement.
1656 	 */
1657 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970)
1658 		sc->sc_swstyle = LE_B20_SSTYLE_PCNETPCI2;
1659 	else
1660 		sc->sc_swstyle = LE_B20_SSTYLE_PCNETPCI3;
1661 	pcn_bcr_write(sc, LE_BCR20, sc->sc_swstyle);
1662 
1663 	/* Initialize the transmit descriptor ring. */
1664 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
1665 	PCN_CDTXSYNC(sc, 0, PCN_NTXDESC,
1666 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1667 	sc->sc_txfree = PCN_NTXDESC;
1668 	sc->sc_txnext = 0;
1669 
1670 	/* Initialize the transmit job descriptors. */
1671 	for (i = 0; i < PCN_TXQUEUELEN; i++)
1672 		sc->sc_txsoft[i].txs_mbuf = NULL;
1673 	sc->sc_txsfree = PCN_TXQUEUELEN;
1674 	sc->sc_txsnext = 0;
1675 	sc->sc_txsdirty = 0;
1676 
1677 	/*
1678 	 * Initialize the receive descriptor and receive job
1679 	 * descriptor rings.
1680 	 */
1681 	for (i = 0; i < PCN_NRXDESC; i++) {
1682 		rxs = &sc->sc_rxsoft[i];
1683 		if (rxs->rxs_mbuf == NULL) {
1684 			if ((error = pcn_add_rxbuf(sc, i)) != 0) {
1685 				printf("%s: unable to allocate or map rx "
1686 				    "buffer %d, error = %d\n",
1687 				    sc->sc_dev.dv_xname, i, error);
1688 				/*
1689 				 * XXX Should attempt to run with fewer receive
1690 				 * XXX buffers instead of just failing.
1691 				 */
1692 				pcn_rxdrain(sc);
1693 				goto out;
1694 			}
1695 		} else
1696 			PCN_INIT_RXDESC(sc, i);
1697 	}
1698 	sc->sc_rxptr = 0;
1699 
1700 	/* Initialize MODE for the initialization block. */
1701 	sc->sc_mode = 0;
1702 	if (ifp->if_flags & IFF_PROMISC)
1703 		sc->sc_mode |= LE_C15_PROM;
1704 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
1705 		sc->sc_mode |= LE_C15_DRCVBC;
1706 
1707 	/*
1708 	 * If we have MII, simply select MII in the MODE register,
1709 	 * and clear ASEL.  Otherwise, let ASEL stand (for now),
1710 	 * and leave PORTSEL alone (it is ignored with ASEL is set).
1711 	 */
1712 	if (sc->sc_flags & PCN_F_HAS_MII) {
1713 		pcn_bcr_write(sc, LE_BCR2,
1714 		    pcn_bcr_read(sc, LE_BCR2) & ~LE_B2_ASEL);
1715 		sc->sc_mode |= LE_C15_PORTSEL(PORTSEL_MII);
1716 
1717 		/*
1718 		 * Disable MII auto-negotiation.  We handle that in
1719 		 * our own MII layer.
1720 		 */
1721 		pcn_bcr_write(sc, LE_BCR32,
1722 		    pcn_bcr_read(sc, LE_BCR32) | LE_B32_DANAS);
1723 	}
1724 
1725 	/*
1726 	 * Set the Tx and Rx descriptor ring addresses in the init
1727 	 * block, the TLEN and RLEN other fields of the init block
1728 	 * MODE register.
1729 	 */
1730 	sc->sc_initblock.init_rdra = htole32(PCN_CDRXADDR(sc, 0));
1731 	sc->sc_initblock.init_tdra = htole32(PCN_CDTXADDR(sc, 0));
1732 	sc->sc_initblock.init_mode = htole32(sc->sc_mode |
1733 	    ((ffs(PCN_NTXDESC) - 1) << 28) |
1734 	    ((ffs(PCN_NRXDESC) - 1) << 20));
1735 
1736 	/* Set the station address in the init block. */
1737 	sc->sc_initblock.init_padr[0] = htole32(enaddr[0] |
1738 	    (enaddr[1] << 8) | (enaddr[2] << 16) | (enaddr[3] << 24));
1739 	sc->sc_initblock.init_padr[1] = htole32(enaddr[4] |
1740 	    (enaddr[5] << 8));
1741 
1742 	/* Set the multicast filter in the init block. */
1743 	pcn_set_filter(sc);
1744 
1745 	/* Initialize CSR3. */
1746 	pcn_csr_write(sc, LE_CSR3, LE_C3_MISSM|LE_C3_IDONM|LE_C3_DXSUFLO);
1747 
1748 	/* Initialize CSR4. */
1749 	pcn_csr_write(sc, LE_CSR4, LE_C4_DMAPLUS|LE_C4_APAD_XMT|
1750 	    LE_C4_MFCOM|LE_C4_RCVCCOM|LE_C4_TXSTRTM);
1751 
1752 	/* Initialize CSR5. */
1753 	sc->sc_csr5 = LE_C5_LTINTEN|LE_C5_SINTE;
1754 	pcn_csr_write(sc, LE_CSR5, sc->sc_csr5);
1755 
1756 	/*
1757 	 * If we have an Am79c971 or greater, initialize CSR7.
1758 	 *
1759 	 * XXX Might be nice to use the MII auto-poll interrupt someday.
1760 	 */
1761 	switch (sc->sc_variant->pcv_chipid) {
1762 	case PARTID_Am79c970:
1763 	case PARTID_Am79c970A:
1764 		/* Not available on these chips. */
1765 		break;
1766 
1767 	default:
1768 		pcn_csr_write(sc, LE_CSR7, LE_C7_FASTSPNDE);
1769 		break;
1770 	}
1771 
1772 	/*
1773 	 * On the Am79c970A and greater, initialize BCR18 to
1774 	 * enable burst mode.
1775 	 *
1776 	 * Also enable the "no underflow" option on the Am79c971 and
1777 	 * higher, which prevents the chip from generating transmit
1778 	 * underflows, yet sill provides decent performance.  Note if
1779 	 * chip is not connected to external SRAM, then we still have
1780 	 * to handle underflow errors (the NOUFLO bit is ignored in
1781 	 * that case).
1782 	 */
1783 	reg = pcn_bcr_read(sc, LE_BCR18);
1784 	switch (sc->sc_variant->pcv_chipid) {
1785 	case PARTID_Am79c970:
1786 		break;
1787 
1788 	case PARTID_Am79c970A:
1789 		reg |= LE_B18_BREADE|LE_B18_BWRITE;
1790 		break;
1791 
1792 	default:
1793 		reg |= LE_B18_BREADE|LE_B18_BWRITE|LE_B18_NOUFLO;
1794 		break;
1795 	}
1796 	pcn_bcr_write(sc, LE_BCR18, reg);
1797 
1798 	/*
1799 	 * Initialize CSR80 (FIFO thresholds for Tx and Rx).
1800 	 */
1801 	pcn_csr_write(sc, LE_CSR80, LE_C80_RCVFW(sc->sc_rcvfw) |
1802 	    LE_C80_XMTSP(sc->sc_xmtsp) | LE_C80_XMTFW(sc->sc_xmtfw));
1803 
1804 	/*
1805 	 * Send the init block to the chip, and wait for it
1806 	 * to be processed.
1807 	 */
1808 	PCN_CDINITSYNC(sc, BUS_DMASYNC_PREWRITE);
1809 	pcn_csr_write(sc, LE_CSR1, PCN_CDINITADDR(sc) & 0xffff);
1810 	pcn_csr_write(sc, LE_CSR2, (PCN_CDINITADDR(sc) >> 16) & 0xffff);
1811 	pcn_csr_write(sc, LE_CSR0, LE_C0_INIT);
1812 	delay(100);
1813 	for (i = 0; i < 10000; i++) {
1814 		if (pcn_csr_read(sc, LE_CSR0) & LE_C0_IDON)
1815 			break;
1816 		delay(10);
1817 	}
1818 	PCN_CDINITSYNC(sc, BUS_DMASYNC_POSTWRITE);
1819 	if (i == 10000) {
1820 		printf("%s: timeout processing init block\n",
1821 		    sc->sc_dev.dv_xname);
1822 		error = EIO;
1823 		goto out;
1824 	}
1825 
1826 	/* Set the media. */
1827 	(void) (*sc->sc_mii.mii_media.ifm_change)(ifp);
1828 
1829 	/* Enable interrupts and external activity (and ACK IDON). */
1830 	pcn_csr_write(sc, LE_CSR0, LE_C0_INEA|LE_C0_STRT|LE_C0_IDON);
1831 
1832 	if (sc->sc_flags & PCN_F_HAS_MII) {
1833 		/* Start the one second MII clock. */
1834 		callout_reset(&sc->sc_tick_ch, hz, pcn_tick, sc);
1835 	}
1836 
1837 	/* ...all done! */
1838 	ifp->if_flags |= IFF_RUNNING;
1839 	ifp->if_flags &= ~IFF_OACTIVE;
1840 
1841  out:
1842 	if (error)
1843 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
1844 	return (error);
1845 }
1846 
1847 /*
1848  * pcn_rxdrain:
1849  *
1850  *	Drain the receive queue.
1851  */
1852 static void
1853 pcn_rxdrain(struct pcn_softc *sc)
1854 {
1855 	struct pcn_rxsoft *rxs;
1856 	int i;
1857 
1858 	for (i = 0; i < PCN_NRXDESC; i++) {
1859 		rxs = &sc->sc_rxsoft[i];
1860 		if (rxs->rxs_mbuf != NULL) {
1861 			bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1862 			m_freem(rxs->rxs_mbuf);
1863 			rxs->rxs_mbuf = NULL;
1864 		}
1865 	}
1866 }
1867 
1868 /*
1869  * pcn_stop:		[ifnet interface function]
1870  *
1871  *	Stop transmission on the interface.
1872  */
1873 static void
1874 pcn_stop(struct ifnet *ifp, int disable)
1875 {
1876 	struct pcn_softc *sc = ifp->if_softc;
1877 	struct pcn_txsoft *txs;
1878 	int i;
1879 
1880 	if (sc->sc_flags & PCN_F_HAS_MII) {
1881 		/* Stop the one second clock. */
1882 		callout_stop(&sc->sc_tick_ch);
1883 
1884 		/* Down the MII. */
1885 		mii_down(&sc->sc_mii);
1886 	}
1887 
1888 	/* Stop the chip. */
1889 	pcn_csr_write(sc, LE_CSR0, LE_C0_STOP);
1890 
1891 	/* Release any queued transmit buffers. */
1892 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
1893 		txs = &sc->sc_txsoft[i];
1894 		if (txs->txs_mbuf != NULL) {
1895 			bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1896 			m_freem(txs->txs_mbuf);
1897 			txs->txs_mbuf = NULL;
1898 		}
1899 	}
1900 
1901 	if (disable)
1902 		pcn_rxdrain(sc);
1903 
1904 	/* Mark the interface as down and cancel the watchdog timer. */
1905 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1906 	ifp->if_timer = 0;
1907 }
1908 
1909 /*
1910  * pcn_add_rxbuf:
1911  *
1912  *	Add a receive buffer to the indicated descriptor.
1913  */
1914 static int
1915 pcn_add_rxbuf(struct pcn_softc *sc, int idx)
1916 {
1917 	struct pcn_rxsoft *rxs = &sc->sc_rxsoft[idx];
1918 	struct mbuf *m;
1919 	int error;
1920 
1921 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1922 	if (m == NULL)
1923 		return (ENOBUFS);
1924 
1925 	MCLGET(m, M_DONTWAIT);
1926 	if ((m->m_flags & M_EXT) == 0) {
1927 		m_freem(m);
1928 		return (ENOBUFS);
1929 	}
1930 
1931 	if (rxs->rxs_mbuf != NULL)
1932 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1933 
1934 	rxs->rxs_mbuf = m;
1935 
1936 	error = bus_dmamap_load(sc->sc_dmat, rxs->rxs_dmamap,
1937 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1938 	    BUS_DMA_READ|BUS_DMA_NOWAIT);
1939 	if (error) {
1940 		printf("%s: can't load rx DMA map %d, error = %d\n",
1941 		    sc->sc_dev.dv_xname, idx, error);
1942 		panic("pcn_add_rxbuf");
1943 	}
1944 
1945 	bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1946 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1947 
1948 	PCN_INIT_RXDESC(sc, idx);
1949 
1950 	return (0);
1951 }
1952 
1953 /*
1954  * pcn_set_filter:
1955  *
1956  *	Set up the receive filter.
1957  */
1958 static void
1959 pcn_set_filter(struct pcn_softc *sc)
1960 {
1961 	struct ethercom *ec = &sc->sc_ethercom;
1962 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1963 	struct ether_multi *enm;
1964 	struct ether_multistep step;
1965 	uint32_t crc;
1966 
1967 	/*
1968 	 * Set up the multicast address filter by passing all multicast
1969 	 * addresses through a CRC generator, and then using the high
1970 	 * order 6 bits as an index into the 64-bit logical address
1971 	 * filter.  The high order bits select the word, while the rest
1972 	 * of the bits select the bit within the word.
1973 	 */
1974 
1975 	if (ifp->if_flags & IFF_PROMISC)
1976 		goto allmulti;
1977 
1978 	sc->sc_initblock.init_ladrf[0] =
1979 	    sc->sc_initblock.init_ladrf[1] =
1980 	    sc->sc_initblock.init_ladrf[2] =
1981 	    sc->sc_initblock.init_ladrf[3] = 0;
1982 
1983 	ETHER_FIRST_MULTI(step, ec, enm);
1984 	while (enm != NULL) {
1985 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
1986 			/*
1987 			 * We must listen to a range of multicast addresses.
1988 			 * For now, just accept all multicasts, rather than
1989 			 * trying to set only those filter bits needed to match
1990 			 * the range.  (At this time, the only use of address
1991 			 * ranges is for IP multicast routing, for which the
1992 			 * range is big enough to require all bits set.)
1993 			 */
1994 			goto allmulti;
1995 		}
1996 
1997 		crc = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN);
1998 
1999 		/* Just want the 6 most significant bits. */
2000 		crc >>= 26;
2001 
2002 		/* Set the corresponding bit in the filter. */
2003 		sc->sc_initblock.init_ladrf[crc >> 4] |=
2004 		    htole16(1 << (crc & 0xf));
2005 
2006 		ETHER_NEXT_MULTI(step, enm);
2007 	}
2008 
2009 	ifp->if_flags &= ~IFF_ALLMULTI;
2010 	return;
2011 
2012  allmulti:
2013 	ifp->if_flags |= IFF_ALLMULTI;
2014 	sc->sc_initblock.init_ladrf[0] =
2015 	    sc->sc_initblock.init_ladrf[1] =
2016 	    sc->sc_initblock.init_ladrf[2] =
2017 	    sc->sc_initblock.init_ladrf[3] = 0xffff;
2018 }
2019 
2020 /*
2021  * pcn_79c970_mediainit:
2022  *
2023  *	Initialize media for the Am79c970.
2024  */
2025 static void
2026 pcn_79c970_mediainit(struct pcn_softc *sc)
2027 {
2028 	const char *sep = "";
2029 
2030 	ifmedia_init(&sc->sc_mii.mii_media, IFM_IMASK, pcn_79c970_mediachange,
2031 	    pcn_79c970_mediastatus);
2032 
2033 #define	ADD(str, m, d)							\
2034 do {									\
2035 	printf("%s%s", sep, str);					\
2036 	ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|(m), (d), NULL);	\
2037 	sep = ", ";							\
2038 } while (/*CONSTCOND*/0)
2039 
2040 	printf("%s: ", sc->sc_dev.dv_xname);
2041 	ADD("10base5", IFM_10_5, PORTSEL_AUI);
2042 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
2043 		ADD("10base5-FDX", IFM_10_5|IFM_FDX, PORTSEL_AUI);
2044 	ADD("10baseT", IFM_10_T, PORTSEL_10T);
2045 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
2046 		ADD("10baseT-FDX", IFM_10_T|IFM_FDX, PORTSEL_10T);
2047 	ADD("auto", IFM_AUTO, 0);
2048 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
2049 		ADD("auto-FDX", IFM_AUTO|IFM_FDX, 0);
2050 	printf("\n");
2051 
2052 	ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
2053 }
2054 
2055 /*
2056  * pcn_79c970_mediastatus:	[ifmedia interface function]
2057  *
2058  *	Get the current interface media status (Am79c970 version).
2059  */
2060 static void
2061 pcn_79c970_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2062 {
2063 	struct pcn_softc *sc = ifp->if_softc;
2064 
2065 	/*
2066 	 * The currently selected media is always the active media.
2067 	 * Note: We have no way to determine what media the AUTO
2068 	 * process picked.
2069 	 */
2070 	ifmr->ifm_active = sc->sc_mii.mii_media.ifm_media;
2071 }
2072 
2073 /*
2074  * pcn_79c970_mediachange:	[ifmedia interface function]
2075  *
2076  *	Set hardware to newly-selected media (Am79c970 version).
2077  */
2078 static int
2079 pcn_79c970_mediachange(struct ifnet *ifp)
2080 {
2081 	struct pcn_softc *sc = ifp->if_softc;
2082 	uint32_t reg;
2083 
2084 	if (IFM_SUBTYPE(sc->sc_mii.mii_media.ifm_media) == IFM_AUTO) {
2085 		/*
2086 		 * CSR15:PORTSEL doesn't matter.  Just set BCR2:ASEL.
2087 		 */
2088 		reg = pcn_bcr_read(sc, LE_BCR2);
2089 		reg |= LE_B2_ASEL;
2090 		pcn_bcr_write(sc, LE_BCR2, reg);
2091 	} else {
2092 		/*
2093 		 * Clear BCR2:ASEL and set the new CSR15:PORTSEL value.
2094 		 */
2095 		reg = pcn_bcr_read(sc, LE_BCR2);
2096 		reg &= ~LE_B2_ASEL;
2097 		pcn_bcr_write(sc, LE_BCR2, reg);
2098 
2099 		reg = pcn_csr_read(sc, LE_CSR15);
2100 		reg = (reg & ~LE_C15_PORTSEL(PORTSEL_MASK)) |
2101 		    LE_C15_PORTSEL(sc->sc_mii.mii_media.ifm_cur->ifm_data);
2102 		pcn_csr_write(sc, LE_CSR15, reg);
2103 	}
2104 
2105 	if ((sc->sc_mii.mii_media.ifm_media & IFM_FDX) != 0) {
2106 		reg = LE_B9_FDEN;
2107 		if (IFM_SUBTYPE(sc->sc_mii.mii_media.ifm_media) == IFM_10_5)
2108 			reg |= LE_B9_AUIFD;
2109 		pcn_bcr_write(sc, LE_BCR9, reg);
2110 	} else
2111 		pcn_bcr_write(sc, LE_BCR9, 0);
2112 
2113 	return (0);
2114 }
2115 
2116 /*
2117  * pcn_79c971_mediainit:
2118  *
2119  *	Initialize media for the Am79c971.
2120  */
2121 static void
2122 pcn_79c971_mediainit(struct pcn_softc *sc)
2123 {
2124 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
2125 
2126 	/* We have MII. */
2127 	sc->sc_flags |= PCN_F_HAS_MII;
2128 
2129 	/*
2130 	 * The built-in 10BASE-T interface is mapped to the MII
2131 	 * on the PCNet-FAST.  Unfortunately, there's no EEPROM
2132 	 * word that tells us which PHY to use.
2133 	 * This driver used to ignore all but the first PHY to
2134 	 * answer, but this code was removed to support multiple
2135 	 * external PHYs. As the default instance will be the first
2136 	 * one to answer, no harm is done by letting the possibly
2137 	 * non-connected internal PHY show up.
2138 	 */
2139 
2140 	/* Initialize our media structures and probe the MII. */
2141 	sc->sc_mii.mii_ifp = ifp;
2142 	sc->sc_mii.mii_readreg = pcn_mii_readreg;
2143 	sc->sc_mii.mii_writereg = pcn_mii_writereg;
2144 	sc->sc_mii.mii_statchg = pcn_mii_statchg;
2145 	ifmedia_init(&sc->sc_mii.mii_media, 0, pcn_79c971_mediachange,
2146 	    pcn_79c971_mediastatus);
2147 
2148 	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
2149 	    MII_OFFSET_ANY, 0);
2150 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
2151 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
2152 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
2153 	} else
2154 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
2155 }
2156 
2157 /*
2158  * pcn_79c971_mediastatus:	[ifmedia interface function]
2159  *
2160  *	Get the current interface media status (Am79c971 version).
2161  */
2162 static void
2163 pcn_79c971_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2164 {
2165 	struct pcn_softc *sc = ifp->if_softc;
2166 
2167 	mii_pollstat(&sc->sc_mii);
2168 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
2169 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
2170 }
2171 
2172 /*
2173  * pcn_79c971_mediachange:	[ifmedia interface function]
2174  *
2175  *	Set hardware to newly-selected media (Am79c971 version).
2176  */
2177 static int
2178 pcn_79c971_mediachange(struct ifnet *ifp)
2179 {
2180 	struct pcn_softc *sc = ifp->if_softc;
2181 
2182 	if (ifp->if_flags & IFF_UP)
2183 		mii_mediachg(&sc->sc_mii);
2184 	return (0);
2185 }
2186 
2187 /*
2188  * pcn_mii_readreg:	[mii interface function]
2189  *
2190  *	Read a PHY register on the MII.
2191  */
2192 static int
2193 pcn_mii_readreg(struct device *self, int phy, int reg)
2194 {
2195 	struct pcn_softc *sc = (void *) self;
2196 	uint32_t rv;
2197 
2198 	pcn_bcr_write(sc, LE_BCR33, reg | (phy << PHYAD_SHIFT));
2199 	rv = pcn_bcr_read(sc, LE_BCR34) & LE_B34_MIIMD;
2200 	if (rv == 0xffff)
2201 		return (0);
2202 
2203 	return (rv);
2204 }
2205 
2206 /*
2207  * pcn_mii_writereg:	[mii interface function]
2208  *
2209  *	Write a PHY register on the MII.
2210  */
2211 static void
2212 pcn_mii_writereg(struct device *self, int phy, int reg, int val)
2213 {
2214 	struct pcn_softc *sc = (void *) self;
2215 
2216 	pcn_bcr_write(sc, LE_BCR33, reg | (phy << PHYAD_SHIFT));
2217 	pcn_bcr_write(sc, LE_BCR34, val);
2218 }
2219 
2220 /*
2221  * pcn_mii_statchg:	[mii interface function]
2222  *
2223  *	Callback from MII layer when media changes.
2224  */
2225 static void
2226 pcn_mii_statchg(struct device *self)
2227 {
2228 	struct pcn_softc *sc = (void *) self;
2229 
2230 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0)
2231 		pcn_bcr_write(sc, LE_BCR9, LE_B9_FDEN);
2232 	else
2233 		pcn_bcr_write(sc, LE_BCR9, 0);
2234 }
2235