xref: /netbsd-src/sys/dev/pci/if_pcn.c (revision ba65fde2d7fefa7d39838fa5fa855e62bd606b5e)
1 /*	$NetBSD: if_pcn.c,v 1.55 2012/07/22 14:33:03 matt 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 1.55 2012/07/22 14:33:03 matt Exp $");
69 
70 #include <sys/param.h>
71 #include <sys/systm.h>
72 #include <sys/callout.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 
82 #include <sys/rnd.h>
83 
84 #include <net/if.h>
85 #include <net/if_dl.h>
86 #include <net/if_media.h>
87 #include <net/if_ether.h>
88 
89 #include <net/bpf.h>
90 
91 #include <sys/bus.h>
92 #include <sys/intr.h>
93 #include <machine/endian.h>
94 
95 #include <dev/mii/mii.h>
96 #include <dev/mii/miivar.h>
97 
98 #include <dev/ic/am79900reg.h>
99 #include <dev/ic/lancereg.h>
100 
101 #include <dev/pci/pcireg.h>
102 #include <dev/pci/pcivar.h>
103 #include <dev/pci/pcidevs.h>
104 
105 #include <dev/pci/if_pcnreg.h>
106 
107 /*
108  * Transmit descriptor list size.  This is arbitrary, but allocate
109  * enough descriptors for 128 pending transmissions, and 4 segments
110  * per packet.  This MUST work out to a power of 2.
111  *
112  * NOTE: We can't have any more than 512 Tx descriptors, SO BE CAREFUL!
113  *
114  * So we play a little trick here.  We give each packet up to 16
115  * DMA segments, but only allocate the max of 512 descriptors.  The
116  * transmit logic can deal with this, we just are hoping to sneak by.
117  */
118 #define	PCN_NTXSEGS		16
119 #define	PCN_NTXSEGS_VMWARE	8	/* bug in VMware's emulation */
120 
121 #define	PCN_TXQUEUELEN		128
122 #define	PCN_TXQUEUELEN_MASK	(PCN_TXQUEUELEN - 1)
123 #define	PCN_NTXDESC		512
124 #define	PCN_NTXDESC_MASK	(PCN_NTXDESC - 1)
125 #define	PCN_NEXTTX(x)		(((x) + 1) & PCN_NTXDESC_MASK)
126 #define	PCN_NEXTTXS(x)		(((x) + 1) & PCN_TXQUEUELEN_MASK)
127 
128 /* Tx interrupt every N + 1 packets. */
129 #define	PCN_TXINTR_MASK		7
130 
131 /*
132  * Receive descriptor list size.  We have one Rx buffer per incoming
133  * packet, so this logic is a little simpler.
134  */
135 #define	PCN_NRXDESC		128
136 #define	PCN_NRXDESC_MASK	(PCN_NRXDESC - 1)
137 #define	PCN_NEXTRX(x)		(((x) + 1) & PCN_NRXDESC_MASK)
138 
139 /*
140  * Control structures are DMA'd to the PCnet chip.  We allocate them in
141  * a single clump that maps to a single DMA segment to make several things
142  * easier.
143  */
144 struct pcn_control_data {
145 	/* The transmit descriptors. */
146 	struct letmd pcd_txdescs[PCN_NTXDESC];
147 
148 	/* The receive descriptors. */
149 	struct lermd pcd_rxdescs[PCN_NRXDESC];
150 
151 	/* The init block. */
152 	struct leinit pcd_initblock;
153 };
154 
155 #define	PCN_CDOFF(x)	offsetof(struct pcn_control_data, x)
156 #define	PCN_CDTXOFF(x)	PCN_CDOFF(pcd_txdescs[(x)])
157 #define	PCN_CDRXOFF(x)	PCN_CDOFF(pcd_rxdescs[(x)])
158 #define	PCN_CDINITOFF	PCN_CDOFF(pcd_initblock)
159 
160 /*
161  * Software state for transmit jobs.
162  */
163 struct pcn_txsoft {
164 	struct mbuf *txs_mbuf;		/* head of our mbuf chain */
165 	bus_dmamap_t txs_dmamap;	/* our DMA map */
166 	int txs_firstdesc;		/* first descriptor in packet */
167 	int txs_lastdesc;		/* last descriptor in packet */
168 };
169 
170 /*
171  * Software state for receive jobs.
172  */
173 struct pcn_rxsoft {
174 	struct mbuf *rxs_mbuf;		/* head of our mbuf chain */
175 	bus_dmamap_t rxs_dmamap;	/* our DMA map */
176 };
177 
178 /*
179  * Description of Rx FIFO watermarks for various revisions.
180  */
181 static const char * const pcn_79c970_rcvfw[] = {
182 	"16 bytes",
183 	"64 bytes",
184 	"128 bytes",
185 	NULL,
186 };
187 
188 static const char * const pcn_79c971_rcvfw[] = {
189 	"16 bytes",
190 	"64 bytes",
191 	"112 bytes",
192 	NULL,
193 };
194 
195 /*
196  * Description of Tx start points for various revisions.
197  */
198 static const char * const pcn_79c970_xmtsp[] = {
199 	"8 bytes",
200 	"64 bytes",
201 	"128 bytes",
202 	"248 bytes",
203 };
204 
205 static const char * const pcn_79c971_xmtsp[] = {
206 	"20 bytes",
207 	"64 bytes",
208 	"128 bytes",
209 	"248 bytes",
210 };
211 
212 static const char * const pcn_79c971_xmtsp_sram[] = {
213 	"44 bytes",
214 	"64 bytes",
215 	"128 bytes",
216 	"store-and-forward",
217 };
218 
219 /*
220  * Description of Tx FIFO watermarks for various revisions.
221  */
222 static const char * const pcn_79c970_xmtfw[] = {
223 	"16 bytes",
224 	"64 bytes",
225 	"128 bytes",
226 	NULL,
227 };
228 
229 static const char * const pcn_79c971_xmtfw[] = {
230 	"16 bytes",
231 	"64 bytes",
232 	"108 bytes",
233 	NULL,
234 };
235 
236 /*
237  * Software state per device.
238  */
239 struct pcn_softc {
240 	device_t sc_dev;		/* generic device information */
241 	bus_space_tag_t sc_st;		/* bus space tag */
242 	bus_space_handle_t sc_sh;	/* bus space handle */
243 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
244 	struct ethercom sc_ethercom;	/* Ethernet common data */
245 
246 	/* Points to our media routines, etc. */
247 	const struct pcn_variant *sc_variant;
248 
249 	void *sc_ih;			/* interrupt cookie */
250 
251 	struct mii_data sc_mii;		/* MII/media information */
252 
253 	callout_t sc_tick_ch;		/* tick callout */
254 
255 	bus_dmamap_t sc_cddmamap;	/* control data DMA map */
256 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
257 
258 	/* Software state for transmit and receive descriptors. */
259 	struct pcn_txsoft sc_txsoft[PCN_TXQUEUELEN];
260 	struct pcn_rxsoft sc_rxsoft[PCN_NRXDESC];
261 
262 	/* Control data structures */
263 	struct pcn_control_data *sc_control_data;
264 #define	sc_txdescs	sc_control_data->pcd_txdescs
265 #define	sc_rxdescs	sc_control_data->pcd_rxdescs
266 #define	sc_initblock	sc_control_data->pcd_initblock
267 
268 #ifdef PCN_EVENT_COUNTERS
269 	/* Event counters. */
270 	struct evcnt sc_ev_txsstall;	/* Tx stalled due to no txs */
271 	struct evcnt sc_ev_txdstall;	/* Tx stalled due to no txd */
272 	struct evcnt sc_ev_txintr;	/* Tx interrupts */
273 	struct evcnt sc_ev_rxintr;	/* Rx interrupts */
274 	struct evcnt sc_ev_babl;	/* BABL in pcn_intr() */
275 	struct evcnt sc_ev_miss;	/* MISS in pcn_intr() */
276 	struct evcnt sc_ev_merr;	/* MERR in pcn_intr() */
277 
278 	struct evcnt sc_ev_txseg1;	/* Tx packets w/ 1 segment */
279 	struct evcnt sc_ev_txseg2;	/* Tx packets w/ 2 segments */
280 	struct evcnt sc_ev_txseg3;	/* Tx packets w/ 3 segments */
281 	struct evcnt sc_ev_txseg4;	/* Tx packets w/ 4 segments */
282 	struct evcnt sc_ev_txseg5;	/* Tx packets w/ 5 segments */
283 	struct evcnt sc_ev_txsegmore;	/* Tx packets w/ more than 5 segments */
284 	struct evcnt sc_ev_txcopy;	/* Tx copies required */
285 #endif /* PCN_EVENT_COUNTERS */
286 
287 	const char * const *sc_rcvfw_desc;	/* Rx FIFO watermark info */
288 	int sc_rcvfw;
289 
290 	const char * const *sc_xmtsp_desc;	/* Tx start point info */
291 	int sc_xmtsp;
292 
293 	const char * const *sc_xmtfw_desc;	/* Tx FIFO watermark info */
294 	int sc_xmtfw;
295 
296 	int sc_flags;			/* misc. flags; see below */
297 	int sc_swstyle;			/* the software style in use */
298 
299 	int sc_txfree;			/* number of free Tx descriptors */
300 	int sc_txnext;			/* next ready Tx descriptor */
301 
302 	int sc_txsfree;			/* number of free Tx jobs */
303 	int sc_txsnext;			/* next free Tx job */
304 	int sc_txsdirty;		/* dirty Tx jobs */
305 
306 	int sc_rxptr;			/* next ready Rx descriptor/job */
307 
308 	uint32_t sc_csr5;		/* prototype CSR5 register */
309 	uint32_t sc_mode;		/* prototype MODE register */
310 
311 	krndsource_t rnd_source;	/* random source */
312 };
313 
314 /* sc_flags */
315 #define	PCN_F_HAS_MII		0x0001	/* has MII */
316 
317 #ifdef PCN_EVENT_COUNTERS
318 #define	PCN_EVCNT_INCR(ev)	(ev)->ev_count++
319 #else
320 #define	PCN_EVCNT_INCR(ev)	/* nothing */
321 #endif
322 
323 #define	PCN_CDTXADDR(sc, x)	((sc)->sc_cddma + PCN_CDTXOFF((x)))
324 #define	PCN_CDRXADDR(sc, x)	((sc)->sc_cddma + PCN_CDRXOFF((x)))
325 #define	PCN_CDINITADDR(sc)	((sc)->sc_cddma + PCN_CDINITOFF)
326 
327 #define	PCN_CDTXSYNC(sc, x, n, ops)					\
328 do {									\
329 	int __x, __n;							\
330 									\
331 	__x = (x);							\
332 	__n = (n);							\
333 									\
334 	/* If it will wrap around, sync to the end of the ring. */	\
335 	if ((__x + __n) > PCN_NTXDESC) {				\
336 		bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,	\
337 		    PCN_CDTXOFF(__x), sizeof(struct letmd) *		\
338 		    (PCN_NTXDESC - __x), (ops));			\
339 		__n -= (PCN_NTXDESC - __x);				\
340 		__x = 0;						\
341 	}								\
342 									\
343 	/* Now sync whatever is left. */				\
344 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
345 	    PCN_CDTXOFF(__x), sizeof(struct letmd) * __n, (ops));	\
346 } while (/*CONSTCOND*/0)
347 
348 #define	PCN_CDRXSYNC(sc, x, ops)					\
349 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
350 	    PCN_CDRXOFF((x)), sizeof(struct lermd), (ops))
351 
352 #define	PCN_CDINITSYNC(sc, ops)						\
353 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
354 	    PCN_CDINITOFF, sizeof(struct leinit), (ops))
355 
356 #define	PCN_INIT_RXDESC(sc, x)						\
357 do {									\
358 	struct pcn_rxsoft *__rxs = &(sc)->sc_rxsoft[(x)];		\
359 	struct lermd *__rmd = &(sc)->sc_rxdescs[(x)];			\
360 	struct mbuf *__m = __rxs->rxs_mbuf;				\
361 									\
362 	/*								\
363 	 * Note: We scoot the packet forward 2 bytes in the buffer	\
364 	 * so that the payload after the Ethernet header is aligned	\
365 	 * to a 4-byte boundary.					\
366 	 */								\
367 	__m->m_data = __m->m_ext.ext_buf + 2;				\
368 									\
369 	if ((sc)->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3) {		\
370 		__rmd->rmd2 =						\
371 		    htole32(__rxs->rxs_dmamap->dm_segs[0].ds_addr + 2);	\
372 		__rmd->rmd0 = 0;					\
373 	} else {							\
374 		__rmd->rmd2 = 0;					\
375 		__rmd->rmd0 =						\
376 		    htole32(__rxs->rxs_dmamap->dm_segs[0].ds_addr + 2);	\
377 	}								\
378 	__rmd->rmd1 = htole32(LE_R1_OWN|LE_R1_ONES| 			\
379 	    (LE_BCNT(MCLBYTES - 2) & LE_R1_BCNT_MASK));			\
380 	PCN_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);\
381 } while(/*CONSTCOND*/0)
382 
383 static void	pcn_start(struct ifnet *);
384 static void	pcn_watchdog(struct ifnet *);
385 static int	pcn_ioctl(struct ifnet *, u_long, void *);
386 static int	pcn_init(struct ifnet *);
387 static void	pcn_stop(struct ifnet *, int);
388 
389 static bool	pcn_shutdown(device_t, int);
390 
391 static void	pcn_reset(struct pcn_softc *);
392 static void	pcn_rxdrain(struct pcn_softc *);
393 static int	pcn_add_rxbuf(struct pcn_softc *, int);
394 static void	pcn_tick(void *);
395 
396 static void	pcn_spnd(struct pcn_softc *);
397 
398 static void	pcn_set_filter(struct pcn_softc *);
399 
400 static int	pcn_intr(void *);
401 static void	pcn_txintr(struct pcn_softc *);
402 static int	pcn_rxintr(struct pcn_softc *);
403 
404 static int	pcn_mii_readreg(device_t, int, int);
405 static void	pcn_mii_writereg(device_t, int, int, int);
406 static void	pcn_mii_statchg(struct ifnet *);
407 
408 static void	pcn_79c970_mediainit(struct pcn_softc *);
409 static int	pcn_79c970_mediachange(struct ifnet *);
410 static void	pcn_79c970_mediastatus(struct ifnet *, struct ifmediareq *);
411 
412 static void	pcn_79c971_mediainit(struct pcn_softc *);
413 
414 /*
415  * Description of a PCnet-PCI variant.  Used to select media access
416  * method, mostly, and to print a nice description of the chip.
417  */
418 static const struct pcn_variant {
419 	const char *pcv_desc;
420 	void (*pcv_mediainit)(struct pcn_softc *);
421 	uint16_t pcv_chipid;
422 } pcn_variants[] = {
423 	{ "Am79c970 PCnet-PCI",
424 	  pcn_79c970_mediainit,
425 	  PARTID_Am79c970 },
426 
427 	{ "Am79c970A PCnet-PCI II",
428 	  pcn_79c970_mediainit,
429 	  PARTID_Am79c970A },
430 
431 	{ "Am79c971 PCnet-FAST",
432 	  pcn_79c971_mediainit,
433 	  PARTID_Am79c971 },
434 
435 	{ "Am79c972 PCnet-FAST+",
436 	  pcn_79c971_mediainit,
437 	  PARTID_Am79c972 },
438 
439 	{ "Am79c973 PCnet-FAST III",
440 	  pcn_79c971_mediainit,
441 	  PARTID_Am79c973 },
442 
443 	{ "Am79c975 PCnet-FAST III",
444 	  pcn_79c971_mediainit,
445 	  PARTID_Am79c975 },
446 
447 	{ "Unknown PCnet-PCI variant",
448 	  pcn_79c971_mediainit,
449 	  0 },
450 };
451 
452 int	pcn_copy_small = 0;
453 
454 static int	pcn_match(device_t, cfdata_t, void *);
455 static void	pcn_attach(device_t, device_t, void *);
456 
457 CFATTACH_DECL_NEW(pcn, sizeof(struct pcn_softc),
458     pcn_match, pcn_attach, NULL, NULL);
459 
460 /*
461  * Routines to read and write the PCnet-PCI CSR/BCR space.
462  */
463 
464 static inline uint32_t
465 pcn_csr_read(struct pcn_softc *sc, int reg)
466 {
467 
468 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
469 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_RDP));
470 }
471 
472 static inline void
473 pcn_csr_write(struct pcn_softc *sc, int reg, uint32_t val)
474 {
475 
476 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
477 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RDP, val);
478 }
479 
480 static inline uint32_t
481 pcn_bcr_read(struct pcn_softc *sc, int reg)
482 {
483 
484 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
485 	return (bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_BDP));
486 }
487 
488 static inline void
489 pcn_bcr_write(struct pcn_softc *sc, int reg, uint32_t val)
490 {
491 
492 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RAP, reg);
493 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_BDP, val);
494 }
495 
496 static bool
497 pcn_is_vmware(const char *enaddr)
498 {
499 
500 	/*
501 	 * VMware uses the OUI 00:0c:29 for auto-generated MAC
502 	 * addresses.
503 	 */
504 	if (enaddr[0] == 0x00 && enaddr[1] == 0x0c && enaddr[2] == 0x29)
505 		return (TRUE);
506 
507 	/*
508 	 * VMware uses the OUI 00:50:56 for manually-set MAC
509 	 * addresses (and some auto-generated ones).
510 	 */
511 	if (enaddr[0] == 0x00 && enaddr[1] == 0x50 && enaddr[2] == 0x56)
512 		return (TRUE);
513 
514 	return (FALSE);
515 }
516 
517 static const struct pcn_variant *
518 pcn_lookup_variant(uint16_t chipid)
519 {
520 	const struct pcn_variant *pcv;
521 
522 	for (pcv = pcn_variants; pcv->pcv_chipid != 0; pcv++) {
523 		if (chipid == pcv->pcv_chipid)
524 			return (pcv);
525 	}
526 
527 	/*
528 	 * This covers unknown chips, which we simply treat like
529 	 * a generic PCnet-FAST.
530 	 */
531 	return (pcv);
532 }
533 
534 static int
535 pcn_match(device_t parent, cfdata_t cf, void *aux)
536 {
537 	struct pci_attach_args *pa = aux;
538 
539 	/*
540 	 * IBM Makes a PCI variant of this card which shows up as a
541 	 * Trident Microsystems 4DWAVE DX (ethernet network, revision 0x25)
542 	 * this card is truly a pcn card, so we have a special case match for
543 	 * it
544 	 */
545 
546 	if (PCI_VENDOR(pa->pa_id) == PCI_VENDOR_TRIDENT &&
547 	    PCI_PRODUCT(pa->pa_id) == PCI_PRODUCT_TRIDENT_4DWAVE_DX &&
548 	    PCI_CLASS(pa->pa_class) == PCI_CLASS_NETWORK)
549 		return(1);
550 
551 	if (PCI_VENDOR(pa->pa_id) != PCI_VENDOR_AMD)
552 		return (0);
553 
554 	switch (PCI_PRODUCT(pa->pa_id)) {
555 	case PCI_PRODUCT_AMD_PCNET_PCI:
556 		/* Beat if_le_pci.c */
557 		return (10);
558 	}
559 
560 	return (0);
561 }
562 
563 static void
564 pcn_attach(device_t parent, device_t self, void *aux)
565 {
566 	struct pcn_softc *sc = device_private(self);
567 	struct pci_attach_args *pa = aux;
568 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
569 	pci_chipset_tag_t pc = pa->pa_pc;
570 	pci_intr_handle_t ih;
571 	const char *intrstr = NULL;
572 	bus_space_tag_t iot, memt;
573 	bus_space_handle_t ioh, memh;
574 	bus_dma_segment_t seg;
575 	int ioh_valid, memh_valid;
576 	int ntxsegs, i, rseg, error;
577 	uint32_t chipid, reg;
578 	uint8_t enaddr[ETHER_ADDR_LEN];
579 	prop_object_t obj;
580 	bool is_vmware;
581 
582 	sc->sc_dev = self;
583 	callout_init(&sc->sc_tick_ch, 0);
584 
585 	aprint_normal(": AMD PCnet-PCI Ethernet\n");
586 
587 	/*
588 	 * Map the device.
589 	 */
590 	ioh_valid = (pci_mapreg_map(pa, PCN_PCI_CBIO, PCI_MAPREG_TYPE_IO, 0,
591 	    &iot, &ioh, NULL, NULL) == 0);
592 	memh_valid = (pci_mapreg_map(pa, PCN_PCI_CBMEM,
593 	    PCI_MAPREG_TYPE_MEM|PCI_MAPREG_MEM_TYPE_32BIT, 0,
594 	    &memt, &memh, NULL, NULL) == 0);
595 
596 	if (memh_valid) {
597 		sc->sc_st = memt;
598 		sc->sc_sh = memh;
599 	} else if (ioh_valid) {
600 		sc->sc_st = iot;
601 		sc->sc_sh = ioh;
602 	} else {
603 		aprint_error_dev(self, "unable to map device registers\n");
604 		return;
605 	}
606 
607 	sc->sc_dmat = pa->pa_dmat;
608 
609 	/* Make sure bus mastering is enabled. */
610 	pci_conf_write(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
611 	    pci_conf_read(pc, pa->pa_tag, PCI_COMMAND_STATUS_REG) |
612 	    PCI_COMMAND_MASTER_ENABLE);
613 
614 	/* power up chip */
615 	if ((error = pci_activate(pa->pa_pc, pa->pa_tag, self,
616 	    NULL)) && error != EOPNOTSUPP) {
617 		aprint_error_dev(self, "cannot activate %d\n", error);
618 		return;
619 	}
620 
621 	/*
622 	 * Reset the chip to a known state.  This also puts the
623 	 * chip into 32-bit mode.
624 	 */
625 	pcn_reset(sc);
626 
627 	/*
628 	 * On some systems with the chip is an on-board device, the
629 	 * EEPROM is not used.  Handle this by reading the MAC address
630 	 * from the CSRs (assuming that boot firmware has written
631 	 * it there).
632 	 */
633 	obj = prop_dictionary_get(device_properties(sc->sc_dev),
634 				  "am79c970-no-eeprom");
635 	if (prop_bool_true(obj)) {
636 	        for (i = 0; i < 3; i++) {
637 			uint32_t val;
638 			val = pcn_csr_read(sc, LE_CSR12 + i);
639 			enaddr[2 * i] = val & 0xff;
640 			enaddr[2 * i + 1] = (val >> 8) & 0xff;
641 		}
642 	} else {
643 		for (i = 0; i < ETHER_ADDR_LEN; i++) {
644 			enaddr[i] = bus_space_read_1(sc->sc_st, sc->sc_sh,
645 			    PCN32_APROM + i);
646 		}
647 	}
648 
649 	/* Check to see if this is a VMware emulated network interface. */
650 	is_vmware = pcn_is_vmware(enaddr);
651 
652 	/*
653 	 * Now that the device is mapped, attempt to figure out what
654 	 * kind of chip we have.  Note that IDL has all 32 bits of
655 	 * the chip ID when we're in 32-bit mode.
656 	 */
657 	chipid = pcn_csr_read(sc, LE_CSR88);
658 	sc->sc_variant = pcn_lookup_variant(CHIPID_PARTID(chipid));
659 
660 	aprint_normal_dev(self, "%s rev %d, Ethernet address %s\n",
661 	    sc->sc_variant->pcv_desc, CHIPID_VER(chipid),
662 	    ether_sprintf(enaddr));
663 
664 	/*
665 	 * VMware has a bug in its network interface emulation; we must
666 	 * limit the number of Tx segments.
667 	 */
668 	if (is_vmware) {
669 		ntxsegs = PCN_NTXSEGS_VMWARE;
670 		prop_dictionary_set_bool(device_properties(sc->sc_dev),
671 					 "am79c970-vmware-tx-bug", TRUE);
672 		aprint_verbose_dev(self,
673 		    "VMware Tx segment count bug detected\n");
674 	} else {
675 		ntxsegs = PCN_NTXSEGS;
676 	}
677 
678 	/*
679 	 * Map and establish our interrupt.
680 	 */
681 	if (pci_intr_map(pa, &ih)) {
682 		aprint_error_dev(self, "unable to map interrupt\n");
683 		return;
684 	}
685 	intrstr = pci_intr_string(pc, ih);
686 	sc->sc_ih = pci_intr_establish(pc, ih, IPL_NET, pcn_intr, sc);
687 	if (sc->sc_ih == NULL) {
688 		aprint_error_dev(self, "unable to establish interrupt");
689 		if (intrstr != NULL)
690 			aprint_error(" at %s", intrstr);
691 		aprint_error("\n");
692 		return;
693 	}
694 	aprint_normal_dev(self, "interrupting at %s\n", intrstr);
695 
696 	/*
697 	 * Allocate the control data structures, and create and load the
698 	 * DMA map for it.
699 	 */
700 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
701 	     sizeof(struct pcn_control_data), PAGE_SIZE, 0, &seg, 1, &rseg,
702 	     0)) != 0) {
703 		aprint_error_dev(self, "unable to allocate control data, "
704 		    "error = %d\n", error);
705 		goto fail_0;
706 	}
707 
708 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
709 	     sizeof(struct pcn_control_data), (void **)&sc->sc_control_data,
710 	     BUS_DMA_COHERENT)) != 0) {
711 		aprint_error_dev(self, "unable to map control data, "
712 		    "error = %d\n", error);
713 		goto fail_1;
714 	}
715 
716 	if ((error = bus_dmamap_create(sc->sc_dmat,
717 	     sizeof(struct pcn_control_data), 1,
718 	     sizeof(struct pcn_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
719 		aprint_error_dev(self, "unable to create control data DMA map, "
720 		    "error = %d\n", error);
721 		goto fail_2;
722 	}
723 
724 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
725 	     sc->sc_control_data, sizeof(struct pcn_control_data), NULL,
726 	     0)) != 0) {
727 		aprint_error_dev(self,
728 		    "unable to load control data DMA map, error = %d\n", error);
729 		goto fail_3;
730 	}
731 
732 	/* Create the transmit buffer DMA maps. */
733 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
734 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
735 		     ntxsegs, MCLBYTES, 0, 0,
736 		     &sc->sc_txsoft[i].txs_dmamap)) != 0) {
737 			aprint_error_dev(self,
738 			    "unable to create tx DMA map %d, error = %d\n",
739 			    i, error);
740 			goto fail_4;
741 		}
742 	}
743 
744 	/* Create the receive buffer DMA maps. */
745 	for (i = 0; i < PCN_NRXDESC; i++) {
746 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
747 		     MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
748 			aprint_error_dev(self,
749 			    "unable to create rx DMA map %d, error = %d\n",
750 			    i, error);
751 			goto fail_5;
752 		}
753 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
754 	}
755 
756 	/* Initialize our media structures. */
757 	(*sc->sc_variant->pcv_mediainit)(sc);
758 
759 	/*
760 	 * Initialize FIFO watermark info.
761 	 */
762 	switch (sc->sc_variant->pcv_chipid) {
763 	case PARTID_Am79c970:
764 	case PARTID_Am79c970A:
765 		sc->sc_rcvfw_desc = pcn_79c970_rcvfw;
766 		sc->sc_xmtsp_desc = pcn_79c970_xmtsp;
767 		sc->sc_xmtfw_desc = pcn_79c970_xmtfw;
768 		break;
769 
770 	default:
771 		sc->sc_rcvfw_desc = pcn_79c971_rcvfw;
772 		/*
773 		 * Read BCR25 to determine how much SRAM is
774 		 * on the board.  If > 0, then we the chip
775 		 * uses different Start Point thresholds.
776 		 *
777 		 * Note BCR25 and BCR26 are loaded from the
778 		 * EEPROM on RST, and unaffected by S_RESET,
779 		 * so we don't really have to worry about
780 		 * them except for this.
781 		 */
782 		reg = pcn_bcr_read(sc, LE_BCR25) & 0x00ff;
783 		if (reg != 0)
784 			sc->sc_xmtsp_desc = pcn_79c971_xmtsp_sram;
785 		else
786 			sc->sc_xmtsp_desc = pcn_79c971_xmtsp;
787 		sc->sc_xmtfw_desc = pcn_79c971_xmtfw;
788 		break;
789 	}
790 
791 	/*
792 	 * Set up defaults -- see the tables above for what these
793 	 * values mean.
794 	 *
795 	 * XXX How should we tune RCVFW and XMTFW?
796 	 */
797 	sc->sc_rcvfw = 1;	/* minimum for full-duplex */
798 	sc->sc_xmtsp = 1;
799 	sc->sc_xmtfw = 0;
800 
801 	ifp = &sc->sc_ethercom.ec_if;
802 	strcpy(ifp->if_xname, device_xname(self));
803 	ifp->if_softc = sc;
804 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
805 	ifp->if_ioctl = pcn_ioctl;
806 	ifp->if_start = pcn_start;
807 	ifp->if_watchdog = pcn_watchdog;
808 	ifp->if_init = pcn_init;
809 	ifp->if_stop = pcn_stop;
810 	IFQ_SET_READY(&ifp->if_snd);
811 
812 	/* Attach the interface. */
813 	if_attach(ifp);
814 	ether_ifattach(ifp, enaddr);
815 	rnd_attach_source(&sc->rnd_source, device_xname(self),
816 	    RND_TYPE_NET, 0);
817 
818 #ifdef PCN_EVENT_COUNTERS
819 	/* Attach event counters. */
820 	evcnt_attach_dynamic(&sc->sc_ev_txsstall, EVCNT_TYPE_MISC,
821 	    NULL, device_xname(self), "txsstall");
822 	evcnt_attach_dynamic(&sc->sc_ev_txdstall, EVCNT_TYPE_MISC,
823 	    NULL, device_xname(self), "txdstall");
824 	evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_INTR,
825 	    NULL, device_xname(self), "txintr");
826 	evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_INTR,
827 	    NULL, device_xname(self), "rxintr");
828 	evcnt_attach_dynamic(&sc->sc_ev_babl, EVCNT_TYPE_MISC,
829 	    NULL, device_xname(self), "babl");
830 	evcnt_attach_dynamic(&sc->sc_ev_miss, EVCNT_TYPE_MISC,
831 	    NULL, device_xname(self), "miss");
832 	evcnt_attach_dynamic(&sc->sc_ev_merr, EVCNT_TYPE_MISC,
833 	    NULL, device_xname(self), "merr");
834 
835 	evcnt_attach_dynamic(&sc->sc_ev_txseg1, EVCNT_TYPE_MISC,
836 	    NULL, device_xname(self), "txseg1");
837 	evcnt_attach_dynamic(&sc->sc_ev_txseg2, EVCNT_TYPE_MISC,
838 	    NULL, device_xname(self), "txseg2");
839 	evcnt_attach_dynamic(&sc->sc_ev_txseg3, EVCNT_TYPE_MISC,
840 	    NULL, device_xname(self), "txseg3");
841 	evcnt_attach_dynamic(&sc->sc_ev_txseg4, EVCNT_TYPE_MISC,
842 	    NULL, device_xname(self), "txseg4");
843 	evcnt_attach_dynamic(&sc->sc_ev_txseg5, EVCNT_TYPE_MISC,
844 	    NULL, device_xname(self), "txseg5");
845 	evcnt_attach_dynamic(&sc->sc_ev_txsegmore, EVCNT_TYPE_MISC,
846 	    NULL, device_xname(self), "txsegmore");
847 	evcnt_attach_dynamic(&sc->sc_ev_txcopy, EVCNT_TYPE_MISC,
848 	    NULL, device_xname(self), "txcopy");
849 #endif /* PCN_EVENT_COUNTERS */
850 
851 	/*
852 	 * Establish power handler with shutdown hook, to make sure
853 	 * the interface is shutdown during reboot.
854 	 */
855 	if (pmf_device_register1(self, NULL, NULL, pcn_shutdown))
856 		pmf_class_network_register(self, ifp);
857 	else
858 		aprint_error_dev(self, "couldn't establish power handler\n");
859 
860 	return;
861 
862 	/*
863 	 * Free any resources we've allocated during the failed attach
864 	 * attempt.  Do this in reverse order and fall through.
865 	 */
866  fail_5:
867 	for (i = 0; i < PCN_NRXDESC; i++) {
868 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
869 			bus_dmamap_destroy(sc->sc_dmat,
870 			    sc->sc_rxsoft[i].rxs_dmamap);
871 	}
872  fail_4:
873 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
874 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
875 			bus_dmamap_destroy(sc->sc_dmat,
876 			    sc->sc_txsoft[i].txs_dmamap);
877 	}
878 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
879  fail_3:
880 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
881  fail_2:
882 	bus_dmamem_unmap(sc->sc_dmat, (void *)sc->sc_control_data,
883 	    sizeof(struct pcn_control_data));
884  fail_1:
885 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
886  fail_0:
887 	return;
888 }
889 
890 /*
891  * pcn_shutdown:
892  *
893  *	Make sure the interface is stopped at reboot time.
894  */
895 static bool
896 pcn_shutdown(device_t self, int howto)
897 {
898 	struct pcn_softc *sc = device_private(self);
899 
900 	pcn_stop(&sc->sc_ethercom.ec_if, 1);
901 	/* explicitly reset the chip for some onboard one with lazy firmware */
902 	pcn_reset(sc);
903 
904 	return true;
905 }
906 
907 /*
908  * pcn_start:		[ifnet interface function]
909  *
910  *	Start packet transmission on the interface.
911  */
912 static void
913 pcn_start(struct ifnet *ifp)
914 {
915 	struct pcn_softc *sc = ifp->if_softc;
916 	struct mbuf *m0, *m;
917 	struct pcn_txsoft *txs;
918 	bus_dmamap_t dmamap;
919 	int error, nexttx, lasttx = -1, ofree, seg;
920 
921 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
922 		return;
923 
924 	/*
925 	 * Remember the previous number of free descriptors and
926 	 * the first descriptor we'll use.
927 	 */
928 	ofree = sc->sc_txfree;
929 
930 	/*
931 	 * Loop through the send queue, setting up transmit descriptors
932 	 * until we drain the queue, or use up all available transmit
933 	 * descriptors.
934 	 */
935 	for (;;) {
936 		/* Grab a packet off the queue. */
937 		IFQ_POLL(&ifp->if_snd, m0);
938 		if (m0 == NULL)
939 			break;
940 		m = NULL;
941 
942 		/* Get a work queue entry. */
943 		if (sc->sc_txsfree == 0) {
944 			PCN_EVCNT_INCR(&sc->sc_ev_txsstall);
945 			break;
946 		}
947 
948 		txs = &sc->sc_txsoft[sc->sc_txsnext];
949 		dmamap = txs->txs_dmamap;
950 
951 		/*
952 		 * Load the DMA map.  If this fails, the packet either
953 		 * didn't fit in the alloted number of segments, or we
954 		 * were short on resources.  In this case, we'll copy
955 		 * and try again.
956 		 */
957 		if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
958 		    BUS_DMA_WRITE|BUS_DMA_NOWAIT) != 0) {
959 			PCN_EVCNT_INCR(&sc->sc_ev_txcopy);
960 			MGETHDR(m, M_DONTWAIT, MT_DATA);
961 			if (m == NULL) {
962 				printf("%s: unable to allocate Tx mbuf\n",
963 				    device_xname(sc->sc_dev));
964 				break;
965 			}
966 			if (m0->m_pkthdr.len > MHLEN) {
967 				MCLGET(m, M_DONTWAIT);
968 				if ((m->m_flags & M_EXT) == 0) {
969 					printf("%s: unable to allocate Tx "
970 					    "cluster\n",
971 					    device_xname(sc->sc_dev));
972 					m_freem(m);
973 					break;
974 				}
975 			}
976 			m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, void *));
977 			m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;
978 			error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
979 			    m, BUS_DMA_WRITE|BUS_DMA_NOWAIT);
980 			if (error) {
981 				printf("%s: unable to load Tx buffer, "
982 				    "error = %d\n", device_xname(sc->sc_dev),
983 				    error);
984 				break;
985 			}
986 		}
987 
988 		/*
989 		 * Ensure we have enough descriptors free to describe
990 		 * the packet.  Note, we always reserve one descriptor
991 		 * at the end of the ring as a termination point, to
992 		 * prevent wrap-around.
993 		 */
994 		if (dmamap->dm_nsegs > (sc->sc_txfree - 1)) {
995 			/*
996 			 * Not enough free descriptors to transmit this
997 			 * packet.  We haven't committed anything yet,
998 			 * so just unload the DMA map, put the packet
999 			 * back on the queue, and punt.  Notify the upper
1000 			 * layer that there are not more slots left.
1001 			 *
1002 			 * XXX We could allocate an mbuf and copy, but
1003 			 * XXX is it worth it?
1004 			 */
1005 			ifp->if_flags |= IFF_OACTIVE;
1006 			bus_dmamap_unload(sc->sc_dmat, dmamap);
1007 			if (m != NULL)
1008 				m_freem(m);
1009 			PCN_EVCNT_INCR(&sc->sc_ev_txdstall);
1010 			break;
1011 		}
1012 
1013 		IFQ_DEQUEUE(&ifp->if_snd, m0);
1014 		if (m != NULL) {
1015 			m_freem(m0);
1016 			m0 = m;
1017 		}
1018 
1019 		/*
1020 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
1021 		 */
1022 
1023 		/* Sync the DMA map. */
1024 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
1025 		    BUS_DMASYNC_PREWRITE);
1026 
1027 #ifdef PCN_EVENT_COUNTERS
1028 		switch (dmamap->dm_nsegs) {
1029 		case 1:
1030 			PCN_EVCNT_INCR(&sc->sc_ev_txseg1);
1031 			break;
1032 		case 2:
1033 			PCN_EVCNT_INCR(&sc->sc_ev_txseg2);
1034 			break;
1035 		case 3:
1036 			PCN_EVCNT_INCR(&sc->sc_ev_txseg3);
1037 			break;
1038 		case 4:
1039 			PCN_EVCNT_INCR(&sc->sc_ev_txseg4);
1040 			break;
1041 		case 5:
1042 			PCN_EVCNT_INCR(&sc->sc_ev_txseg5);
1043 			break;
1044 		default:
1045 			PCN_EVCNT_INCR(&sc->sc_ev_txsegmore);
1046 			break;
1047 		}
1048 #endif /* PCN_EVENT_COUNTERS */
1049 
1050 		/*
1051 		 * Initialize the transmit descriptors.
1052 		 */
1053 		if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3) {
1054 			for (nexttx = sc->sc_txnext, seg = 0;
1055 			     seg < dmamap->dm_nsegs;
1056 			     seg++, nexttx = PCN_NEXTTX(nexttx)) {
1057 				/*
1058 				 * If this is the first descriptor we're
1059 				 * enqueueing, don't set the OWN bit just
1060 				 * yet.  That could cause a race condition.
1061 				 * We'll do it below.
1062 				 */
1063 				sc->sc_txdescs[nexttx].tmd0 = 0;
1064 				sc->sc_txdescs[nexttx].tmd2 =
1065 				    htole32(dmamap->dm_segs[seg].ds_addr);
1066 				sc->sc_txdescs[nexttx].tmd1 =
1067 				    htole32(LE_T1_ONES |
1068 				    (nexttx == sc->sc_txnext ? 0 : LE_T1_OWN) |
1069 				    (LE_BCNT(dmamap->dm_segs[seg].ds_len) &
1070 				     LE_T1_BCNT_MASK));
1071 				lasttx = nexttx;
1072 			}
1073 		} else {
1074 			for (nexttx = sc->sc_txnext, seg = 0;
1075 			     seg < dmamap->dm_nsegs;
1076 			     seg++, nexttx = PCN_NEXTTX(nexttx)) {
1077 				/*
1078 				 * If this is the first descriptor we're
1079 				 * enqueueing, don't set the OWN bit just
1080 				 * yet.  That could cause a race condition.
1081 				 * We'll do it below.
1082 				 */
1083 				sc->sc_txdescs[nexttx].tmd0 =
1084 				    htole32(dmamap->dm_segs[seg].ds_addr);
1085 				sc->sc_txdescs[nexttx].tmd2 = 0;
1086 				sc->sc_txdescs[nexttx].tmd1 =
1087 				    htole32(LE_T1_ONES |
1088 				    (nexttx == sc->sc_txnext ? 0 : LE_T1_OWN) |
1089 				    (LE_BCNT(dmamap->dm_segs[seg].ds_len) &
1090 				     LE_T1_BCNT_MASK));
1091 				lasttx = nexttx;
1092 			}
1093 		}
1094 
1095 		KASSERT(lasttx != -1);
1096 		/* Interrupt on the packet, if appropriate. */
1097 		if ((sc->sc_txsnext & PCN_TXINTR_MASK) == 0)
1098 			sc->sc_txdescs[lasttx].tmd1 |= htole32(LE_T1_LTINT);
1099 
1100 		/* Set `start of packet' and `end of packet' appropriately. */
1101 		sc->sc_txdescs[lasttx].tmd1 |= htole32(LE_T1_ENP);
1102 		sc->sc_txdescs[sc->sc_txnext].tmd1 |=
1103 		    htole32(LE_T1_OWN|LE_T1_STP);
1104 
1105 		/* Sync the descriptors we're using. */
1106 		PCN_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
1107 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1108 
1109 		/* Kick the transmitter. */
1110 		pcn_csr_write(sc, LE_CSR0, LE_C0_INEA|LE_C0_TDMD);
1111 
1112 		/*
1113 		 * Store a pointer to the packet so we can free it later,
1114 		 * and remember what txdirty will be once the packet is
1115 		 * done.
1116 		 */
1117 		txs->txs_mbuf = m0;
1118 		txs->txs_firstdesc = sc->sc_txnext;
1119 		txs->txs_lastdesc = lasttx;
1120 
1121 		/* Advance the tx pointer. */
1122 		sc->sc_txfree -= dmamap->dm_nsegs;
1123 		sc->sc_txnext = nexttx;
1124 
1125 		sc->sc_txsfree--;
1126 		sc->sc_txsnext = PCN_NEXTTXS(sc->sc_txsnext);
1127 
1128 		/* Pass the packet to any BPF listeners. */
1129 		bpf_mtap(ifp, m0);
1130 	}
1131 
1132 	if (sc->sc_txsfree == 0 || sc->sc_txfree == 0) {
1133 		/* No more slots left; notify upper layer. */
1134 		ifp->if_flags |= IFF_OACTIVE;
1135 	}
1136 
1137 	if (sc->sc_txfree != ofree) {
1138 		/* Set a watchdog timer in case the chip flakes out. */
1139 		ifp->if_timer = 5;
1140 	}
1141 }
1142 
1143 /*
1144  * pcn_watchdog:	[ifnet interface function]
1145  *
1146  *	Watchdog timer handler.
1147  */
1148 static void
1149 pcn_watchdog(struct ifnet *ifp)
1150 {
1151 	struct pcn_softc *sc = ifp->if_softc;
1152 
1153 	/*
1154 	 * Since we're not interrupting every packet, sweep
1155 	 * up before we report an error.
1156 	 */
1157 	pcn_txintr(sc);
1158 
1159 	if (sc->sc_txfree != PCN_NTXDESC) {
1160 		printf("%s: device timeout (txfree %d txsfree %d)\n",
1161 		    device_xname(sc->sc_dev), sc->sc_txfree, sc->sc_txsfree);
1162 		ifp->if_oerrors++;
1163 
1164 		/* Reset the interface. */
1165 		(void) pcn_init(ifp);
1166 	}
1167 
1168 	/* Try to get more packets going. */
1169 	pcn_start(ifp);
1170 }
1171 
1172 /*
1173  * pcn_ioctl:		[ifnet interface function]
1174  *
1175  *	Handle control requests from the operator.
1176  */
1177 static int
1178 pcn_ioctl(struct ifnet *ifp, u_long cmd, void *data)
1179 {
1180 	struct pcn_softc *sc = ifp->if_softc;
1181 	struct ifreq *ifr = (struct ifreq *) data;
1182 	int s, error;
1183 
1184 	s = splnet();
1185 
1186 	switch (cmd) {
1187 	case SIOCSIFMEDIA:
1188 	case SIOCGIFMEDIA:
1189 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
1190 		break;
1191 
1192 	default:
1193 		error = ether_ioctl(ifp, cmd, data);
1194 		if (error == ENETRESET) {
1195 			/*
1196 			 * Multicast list has changed; set the hardware filter
1197 			 * accordingly.
1198 			 */
1199 			if (ifp->if_flags & IFF_RUNNING)
1200 				error = pcn_init(ifp);
1201 			else
1202 				error = 0;
1203 		}
1204 		break;
1205 	}
1206 
1207 	/* Try to get more packets going. */
1208 	pcn_start(ifp);
1209 
1210 	splx(s);
1211 	return (error);
1212 }
1213 
1214 /*
1215  * pcn_intr:
1216  *
1217  *	Interrupt service routine.
1218  */
1219 static int
1220 pcn_intr(void *arg)
1221 {
1222 	struct pcn_softc *sc = arg;
1223 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1224 	uint32_t csr0;
1225 	int wantinit, handled = 0;
1226 
1227 	for (wantinit = 0; wantinit == 0;) {
1228 		csr0 = pcn_csr_read(sc, LE_CSR0);
1229 		if ((csr0 & LE_C0_INTR) == 0)
1230 			break;
1231 
1232 		rnd_add_uint32(&sc->rnd_source, csr0);
1233 
1234 		/* ACK the bits and re-enable interrupts. */
1235 		pcn_csr_write(sc, LE_CSR0, csr0 &
1236 		    (LE_C0_INEA|LE_C0_BABL|LE_C0_MISS|LE_C0_MERR|LE_C0_RINT|
1237 		     LE_C0_TINT|LE_C0_IDON));
1238 
1239 		handled = 1;
1240 
1241 		if (csr0 & LE_C0_RINT) {
1242 			PCN_EVCNT_INCR(&sc->sc_ev_rxintr);
1243 			wantinit = pcn_rxintr(sc);
1244 		}
1245 
1246 		if (csr0 & LE_C0_TINT) {
1247 			PCN_EVCNT_INCR(&sc->sc_ev_txintr);
1248 			pcn_txintr(sc);
1249 		}
1250 
1251 		if (csr0 & LE_C0_ERR) {
1252 			if (csr0 & LE_C0_BABL) {
1253 				PCN_EVCNT_INCR(&sc->sc_ev_babl);
1254 				ifp->if_oerrors++;
1255 			}
1256 			if (csr0 & LE_C0_MISS) {
1257 				PCN_EVCNT_INCR(&sc->sc_ev_miss);
1258 				ifp->if_ierrors++;
1259 			}
1260 			if (csr0 & LE_C0_MERR) {
1261 				PCN_EVCNT_INCR(&sc->sc_ev_merr);
1262 				printf("%s: memory error\n",
1263 				    device_xname(sc->sc_dev));
1264 				wantinit = 1;
1265 				break;
1266 			}
1267 		}
1268 
1269 		if ((csr0 & LE_C0_RXON) == 0) {
1270 			printf("%s: receiver disabled\n",
1271 			    device_xname(sc->sc_dev));
1272 			ifp->if_ierrors++;
1273 			wantinit = 1;
1274 		}
1275 
1276 		if ((csr0 & LE_C0_TXON) == 0) {
1277 			printf("%s: transmitter disabled\n",
1278 			    device_xname(sc->sc_dev));
1279 			ifp->if_oerrors++;
1280 			wantinit = 1;
1281 		}
1282 	}
1283 
1284 	if (handled) {
1285 		if (wantinit)
1286 			pcn_init(ifp);
1287 
1288 		/* Try to get more packets going. */
1289 		pcn_start(ifp);
1290 	}
1291 
1292 	return (handled);
1293 }
1294 
1295 /*
1296  * pcn_spnd:
1297  *
1298  *	Suspend the chip.
1299  */
1300 static void
1301 pcn_spnd(struct pcn_softc *sc)
1302 {
1303 	int i;
1304 
1305 	pcn_csr_write(sc, LE_CSR5, sc->sc_csr5 | LE_C5_SPND);
1306 
1307 	for (i = 0; i < 10000; i++) {
1308 		if (pcn_csr_read(sc, LE_CSR5) & LE_C5_SPND)
1309 			return;
1310 		delay(5);
1311 	}
1312 
1313 	printf("%s: WARNING: chip failed to enter suspended state\n",
1314 	    device_xname(sc->sc_dev));
1315 }
1316 
1317 /*
1318  * pcn_txintr:
1319  *
1320  *	Helper; handle transmit interrupts.
1321  */
1322 static void
1323 pcn_txintr(struct pcn_softc *sc)
1324 {
1325 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1326 	struct pcn_txsoft *txs;
1327 	uint32_t tmd1, tmd2, tmd;
1328 	int i, j;
1329 
1330 	ifp->if_flags &= ~IFF_OACTIVE;
1331 
1332 	/*
1333 	 * Go through our Tx list and free mbufs for those
1334 	 * frames which have been transmitted.
1335 	 */
1336 	for (i = sc->sc_txsdirty; sc->sc_txsfree != PCN_TXQUEUELEN;
1337 	     i = PCN_NEXTTXS(i), sc->sc_txsfree++) {
1338 		txs = &sc->sc_txsoft[i];
1339 
1340 		PCN_CDTXSYNC(sc, txs->txs_firstdesc, txs->txs_dmamap->dm_nsegs,
1341 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1342 
1343 		tmd1 = le32toh(sc->sc_txdescs[txs->txs_lastdesc].tmd1);
1344 		if (tmd1 & LE_T1_OWN)
1345 			break;
1346 
1347 		/*
1348 		 * Slightly annoying -- we have to loop through the
1349 		 * descriptors we've used looking for ERR, since it
1350 		 * can appear on any descriptor in the chain.
1351 		 */
1352 		for (j = txs->txs_firstdesc;; j = PCN_NEXTTX(j)) {
1353 			tmd = le32toh(sc->sc_txdescs[j].tmd1);
1354 			if (tmd & LE_T1_ERR) {
1355 				ifp->if_oerrors++;
1356 				if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3)
1357 					tmd2 = le32toh(sc->sc_txdescs[j].tmd0);
1358 				else
1359 					tmd2 = le32toh(sc->sc_txdescs[j].tmd2);
1360 				if (tmd2 & LE_T2_UFLO) {
1361 					if (sc->sc_xmtsp < LE_C80_XMTSP_MAX) {
1362 						sc->sc_xmtsp++;
1363 						printf("%s: transmit "
1364 						    "underrun; new threshold: "
1365 						    "%s\n",
1366 						    device_xname(sc->sc_dev),
1367 						    sc->sc_xmtsp_desc[
1368 						    sc->sc_xmtsp]);
1369 						pcn_spnd(sc);
1370 						pcn_csr_write(sc, LE_CSR80,
1371 						    LE_C80_RCVFW(sc->sc_rcvfw) |
1372 						    LE_C80_XMTSP(sc->sc_xmtsp) |
1373 						    LE_C80_XMTFW(sc->sc_xmtfw));
1374 						pcn_csr_write(sc, LE_CSR5,
1375 						    sc->sc_csr5);
1376 					} else {
1377 						printf("%s: transmit "
1378 						    "underrun\n",
1379 						    device_xname(sc->sc_dev));
1380 					}
1381 				} else if (tmd2 & LE_T2_BUFF) {
1382 					printf("%s: transmit buffer error\n",
1383 					    device_xname(sc->sc_dev));
1384 				}
1385 				if (tmd2 & LE_T2_LCOL)
1386 					ifp->if_collisions++;
1387 				if (tmd2 & LE_T2_RTRY)
1388 					ifp->if_collisions += 16;
1389 				goto next_packet;
1390 			}
1391 			if (j == txs->txs_lastdesc)
1392 				break;
1393 		}
1394 		if (tmd1 & LE_T1_ONE)
1395 			ifp->if_collisions++;
1396 		else if (tmd & LE_T1_MORE) {
1397 			/* Real number is unknown. */
1398 			ifp->if_collisions += 2;
1399 		}
1400 		ifp->if_opackets++;
1401  next_packet:
1402 		sc->sc_txfree += txs->txs_dmamap->dm_nsegs;
1403 		bus_dmamap_sync(sc->sc_dmat, txs->txs_dmamap,
1404 		    0, txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
1405 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1406 		m_freem(txs->txs_mbuf);
1407 		txs->txs_mbuf = NULL;
1408 	}
1409 
1410 	/* Update the dirty transmit buffer pointer. */
1411 	sc->sc_txsdirty = i;
1412 
1413 	/*
1414 	 * If there are no more pending transmissions, cancel the watchdog
1415 	 * timer.
1416 	 */
1417 	if (sc->sc_txsfree == PCN_TXQUEUELEN)
1418 		ifp->if_timer = 0;
1419 }
1420 
1421 /*
1422  * pcn_rxintr:
1423  *
1424  *	Helper; handle receive interrupts.
1425  */
1426 static int
1427 pcn_rxintr(struct pcn_softc *sc)
1428 {
1429 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1430 	struct pcn_rxsoft *rxs;
1431 	struct mbuf *m;
1432 	uint32_t rmd1;
1433 	int i, len;
1434 
1435 	for (i = sc->sc_rxptr;; i = PCN_NEXTRX(i)) {
1436 		rxs = &sc->sc_rxsoft[i];
1437 
1438 		PCN_CDRXSYNC(sc, i, BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
1439 
1440 		rmd1 = le32toh(sc->sc_rxdescs[i].rmd1);
1441 
1442 		if (rmd1 & LE_R1_OWN)
1443 			break;
1444 
1445 		/*
1446 		 * Check for errors and make sure the packet fit into
1447 		 * a single buffer.  We have structured this block of
1448 		 * code the way it is in order to compress it into
1449 		 * one test in the common case (no error).
1450 		 */
1451 		if (__predict_false((rmd1 & (LE_R1_STP|LE_R1_ENP|LE_R1_ERR)) !=
1452 		    (LE_R1_STP|LE_R1_ENP))) {
1453 			/* Make sure the packet is in a single buffer. */
1454 			if ((rmd1 & (LE_R1_STP|LE_R1_ENP)) !=
1455 			    (LE_R1_STP|LE_R1_ENP)) {
1456 				printf("%s: packet spilled into next buffer\n",
1457 				    device_xname(sc->sc_dev));
1458 				return (1);	/* pcn_intr() will re-init */
1459 			}
1460 
1461 			/*
1462 			 * If the packet had an error, simple recycle the
1463 			 * buffer.
1464 			 */
1465 			if (rmd1 & LE_R1_ERR) {
1466 				ifp->if_ierrors++;
1467 				/*
1468 				 * If we got an overflow error, chances
1469 				 * are there will be a CRC error.  In
1470 				 * this case, just print the overflow
1471 				 * error, and skip the others.
1472 				 */
1473 				if (rmd1 & LE_R1_OFLO)
1474 					printf("%s: overflow error\n",
1475 					    device_xname(sc->sc_dev));
1476 				else {
1477 #define	PRINTIT(x, str)							\
1478 					if (rmd1 & (x))			\
1479 						printf("%s: %s\n",	\
1480 						    device_xname(sc->sc_dev), \
1481 						    str);
1482 					PRINTIT(LE_R1_FRAM, "framing error");
1483 					PRINTIT(LE_R1_CRC, "CRC error");
1484 					PRINTIT(LE_R1_BUFF, "buffer error");
1485 				}
1486 #undef PRINTIT
1487 				PCN_INIT_RXDESC(sc, i);
1488 				continue;
1489 			}
1490 		}
1491 
1492 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1493 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
1494 
1495 		/*
1496 		 * No errors; receive the packet.
1497 		 */
1498 		if (sc->sc_swstyle == LE_B20_SSTYLE_PCNETPCI3)
1499 			len = le32toh(sc->sc_rxdescs[i].rmd0) & LE_R1_BCNT_MASK;
1500 		else
1501 			len = le32toh(sc->sc_rxdescs[i].rmd2) & LE_R1_BCNT_MASK;
1502 
1503 		/*
1504 		 * The LANCE family includes the CRC with every packet;
1505 		 * trim it off here.
1506 		 */
1507 		len -= ETHER_CRC_LEN;
1508 
1509 		/*
1510 		 * If the packet is small enough to fit in a
1511 		 * single header mbuf, allocate one and copy
1512 		 * the data into it.  This greatly reduces
1513 		 * memory consumption when we receive lots
1514 		 * of small packets.
1515 		 *
1516 		 * Otherwise, we add a new buffer to the receive
1517 		 * chain.  If this fails, we drop the packet and
1518 		 * recycle the old buffer.
1519 		 */
1520 		if (pcn_copy_small != 0 && len <= (MHLEN - 2)) {
1521 			MGETHDR(m, M_DONTWAIT, MT_DATA);
1522 			if (m == NULL)
1523 				goto dropit;
1524 			m->m_data += 2;
1525 			memcpy(mtod(m, void *),
1526 			    mtod(rxs->rxs_mbuf, void *), len);
1527 			PCN_INIT_RXDESC(sc, i);
1528 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1529 			    rxs->rxs_dmamap->dm_mapsize,
1530 			    BUS_DMASYNC_PREREAD);
1531 		} else {
1532 			m = rxs->rxs_mbuf;
1533 			if (pcn_add_rxbuf(sc, i) != 0) {
1534  dropit:
1535 				ifp->if_ierrors++;
1536 				PCN_INIT_RXDESC(sc, i);
1537 				bus_dmamap_sync(sc->sc_dmat,
1538 				    rxs->rxs_dmamap, 0,
1539 				    rxs->rxs_dmamap->dm_mapsize,
1540 				    BUS_DMASYNC_PREREAD);
1541 				continue;
1542 			}
1543 		}
1544 
1545 		m->m_pkthdr.rcvif = ifp;
1546 		m->m_pkthdr.len = m->m_len = len;
1547 
1548 		/* Pass this up to any BPF listeners. */
1549 		bpf_mtap(ifp, m);
1550 
1551 		/* Pass it on. */
1552 		(*ifp->if_input)(ifp, m);
1553 		ifp->if_ipackets++;
1554 	}
1555 
1556 	/* Update the receive pointer. */
1557 	sc->sc_rxptr = i;
1558 	return (0);
1559 }
1560 
1561 /*
1562  * pcn_tick:
1563  *
1564  *	One second timer, used to tick the MII.
1565  */
1566 static void
1567 pcn_tick(void *arg)
1568 {
1569 	struct pcn_softc *sc = arg;
1570 	int s;
1571 
1572 	s = splnet();
1573 	mii_tick(&sc->sc_mii);
1574 	splx(s);
1575 
1576 	callout_reset(&sc->sc_tick_ch, hz, pcn_tick, sc);
1577 }
1578 
1579 /*
1580  * pcn_reset:
1581  *
1582  *	Perform a soft reset on the PCnet-PCI.
1583  */
1584 static void
1585 pcn_reset(struct pcn_softc *sc)
1586 {
1587 
1588 	/*
1589 	 * The PCnet-PCI chip is reset by reading from the
1590 	 * RESET register.  Note that while the NE2100 LANCE
1591 	 * boards require a write after the read, the PCnet-PCI
1592 	 * chips do not require this.
1593 	 *
1594 	 * Since we don't know if we're in 16-bit or 32-bit
1595 	 * mode right now, issue both (it's safe) in the
1596 	 * hopes that one will succeed.
1597 	 */
1598 	(void) bus_space_read_2(sc->sc_st, sc->sc_sh, PCN16_RESET);
1599 	(void) bus_space_read_4(sc->sc_st, sc->sc_sh, PCN32_RESET);
1600 
1601 	/* Wait 1ms for it to finish. */
1602 	delay(1000);
1603 
1604 	/*
1605 	 * Select 32-bit I/O mode by issuing a 32-bit write to the
1606 	 * RDP.  Since the RAP is 0 after a reset, writing a 0
1607 	 * to RDP is safe (since it simply clears CSR0).
1608 	 */
1609 	bus_space_write_4(sc->sc_st, sc->sc_sh, PCN32_RDP, 0);
1610 }
1611 
1612 /*
1613  * pcn_init:		[ifnet interface function]
1614  *
1615  *	Initialize the interface.  Must be called at splnet().
1616  */
1617 static int
1618 pcn_init(struct ifnet *ifp)
1619 {
1620 	struct pcn_softc *sc = ifp->if_softc;
1621 	struct pcn_rxsoft *rxs;
1622 	const uint8_t *enaddr = CLLADDR(ifp->if_sadl);
1623 	int i, error = 0;
1624 	uint32_t reg;
1625 
1626 	/* Cancel any pending I/O. */
1627 	pcn_stop(ifp, 0);
1628 
1629 	/* Reset the chip to a known state. */
1630 	pcn_reset(sc);
1631 
1632 	/*
1633 	 * On the Am79c970, select SSTYLE 2, and SSTYLE 3 on everything
1634 	 * else.
1635 	 *
1636 	 * XXX It'd be really nice to use SSTYLE 2 on all the chips,
1637 	 * because the structure layout is compatible with ILACC,
1638 	 * but the burst mode is only available in SSTYLE 3, and
1639 	 * burst mode should provide some performance enhancement.
1640 	 */
1641 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970)
1642 		sc->sc_swstyle = LE_B20_SSTYLE_PCNETPCI2;
1643 	else
1644 		sc->sc_swstyle = LE_B20_SSTYLE_PCNETPCI3;
1645 	pcn_bcr_write(sc, LE_BCR20, sc->sc_swstyle);
1646 
1647 	/* Initialize the transmit descriptor ring. */
1648 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
1649 	PCN_CDTXSYNC(sc, 0, PCN_NTXDESC,
1650 	    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
1651 	sc->sc_txfree = PCN_NTXDESC;
1652 	sc->sc_txnext = 0;
1653 
1654 	/* Initialize the transmit job descriptors. */
1655 	for (i = 0; i < PCN_TXQUEUELEN; i++)
1656 		sc->sc_txsoft[i].txs_mbuf = NULL;
1657 	sc->sc_txsfree = PCN_TXQUEUELEN;
1658 	sc->sc_txsnext = 0;
1659 	sc->sc_txsdirty = 0;
1660 
1661 	/*
1662 	 * Initialize the receive descriptor and receive job
1663 	 * descriptor rings.
1664 	 */
1665 	for (i = 0; i < PCN_NRXDESC; i++) {
1666 		rxs = &sc->sc_rxsoft[i];
1667 		if (rxs->rxs_mbuf == NULL) {
1668 			if ((error = pcn_add_rxbuf(sc, i)) != 0) {
1669 				printf("%s: unable to allocate or map rx "
1670 				    "buffer %d, error = %d\n",
1671 				    device_xname(sc->sc_dev), i, error);
1672 				/*
1673 				 * XXX Should attempt to run with fewer receive
1674 				 * XXX buffers instead of just failing.
1675 				 */
1676 				pcn_rxdrain(sc);
1677 				goto out;
1678 			}
1679 		} else
1680 			PCN_INIT_RXDESC(sc, i);
1681 	}
1682 	sc->sc_rxptr = 0;
1683 
1684 	/* Initialize MODE for the initialization block. */
1685 	sc->sc_mode = 0;
1686 	if (ifp->if_flags & IFF_PROMISC)
1687 		sc->sc_mode |= LE_C15_PROM;
1688 	if ((ifp->if_flags & IFF_BROADCAST) == 0)
1689 		sc->sc_mode |= LE_C15_DRCVBC;
1690 
1691 	/*
1692 	 * If we have MII, simply select MII in the MODE register,
1693 	 * and clear ASEL.  Otherwise, let ASEL stand (for now),
1694 	 * and leave PORTSEL alone (it is ignored with ASEL is set).
1695 	 */
1696 	if (sc->sc_flags & PCN_F_HAS_MII) {
1697 		pcn_bcr_write(sc, LE_BCR2,
1698 		    pcn_bcr_read(sc, LE_BCR2) & ~LE_B2_ASEL);
1699 		sc->sc_mode |= LE_C15_PORTSEL(PORTSEL_MII);
1700 
1701 		/*
1702 		 * Disable MII auto-negotiation.  We handle that in
1703 		 * our own MII layer.
1704 		 */
1705 		pcn_bcr_write(sc, LE_BCR32,
1706 		    pcn_bcr_read(sc, LE_BCR32) | LE_B32_DANAS);
1707 	}
1708 
1709 	/*
1710 	 * Set the Tx and Rx descriptor ring addresses in the init
1711 	 * block, the TLEN and RLEN other fields of the init block
1712 	 * MODE register.
1713 	 */
1714 	sc->sc_initblock.init_rdra = htole32(PCN_CDRXADDR(sc, 0));
1715 	sc->sc_initblock.init_tdra = htole32(PCN_CDTXADDR(sc, 0));
1716 	sc->sc_initblock.init_mode = htole32(sc->sc_mode |
1717 	    ((ffs(PCN_NTXDESC) - 1) << 28) |
1718 	    ((ffs(PCN_NRXDESC) - 1) << 20));
1719 
1720 	/* Set the station address in the init block. */
1721 	sc->sc_initblock.init_padr[0] = htole32(enaddr[0] |
1722 	    (enaddr[1] << 8) | (enaddr[2] << 16) | (enaddr[3] << 24));
1723 	sc->sc_initblock.init_padr[1] = htole32(enaddr[4] |
1724 	    (enaddr[5] << 8));
1725 
1726 	/* Set the multicast filter in the init block. */
1727 	pcn_set_filter(sc);
1728 
1729 	/* Initialize CSR3. */
1730 	pcn_csr_write(sc, LE_CSR3, LE_C3_MISSM|LE_C3_IDONM|LE_C3_DXSUFLO);
1731 
1732 	/* Initialize CSR4. */
1733 	pcn_csr_write(sc, LE_CSR4, LE_C4_DMAPLUS|LE_C4_APAD_XMT|
1734 	    LE_C4_MFCOM|LE_C4_RCVCCOM|LE_C4_TXSTRTM);
1735 
1736 	/* Initialize CSR5. */
1737 	sc->sc_csr5 = LE_C5_LTINTEN|LE_C5_SINTE;
1738 	pcn_csr_write(sc, LE_CSR5, sc->sc_csr5);
1739 
1740 	/*
1741 	 * If we have an Am79c971 or greater, initialize CSR7.
1742 	 *
1743 	 * XXX Might be nice to use the MII auto-poll interrupt someday.
1744 	 */
1745 	switch (sc->sc_variant->pcv_chipid) {
1746 	case PARTID_Am79c970:
1747 	case PARTID_Am79c970A:
1748 		/* Not available on these chips. */
1749 		break;
1750 
1751 	default:
1752 		pcn_csr_write(sc, LE_CSR7, LE_C7_FASTSPNDE);
1753 		break;
1754 	}
1755 
1756 	/*
1757 	 * On the Am79c970A and greater, initialize BCR18 to
1758 	 * enable burst mode.
1759 	 *
1760 	 * Also enable the "no underflow" option on the Am79c971 and
1761 	 * higher, which prevents the chip from generating transmit
1762 	 * underflows, yet sill provides decent performance.  Note if
1763 	 * chip is not connected to external SRAM, then we still have
1764 	 * to handle underflow errors (the NOUFLO bit is ignored in
1765 	 * that case).
1766 	 */
1767 	reg = pcn_bcr_read(sc, LE_BCR18);
1768 	switch (sc->sc_variant->pcv_chipid) {
1769 	case PARTID_Am79c970:
1770 		break;
1771 
1772 	case PARTID_Am79c970A:
1773 		reg |= LE_B18_BREADE|LE_B18_BWRITE;
1774 		break;
1775 
1776 	default:
1777 		reg |= LE_B18_BREADE|LE_B18_BWRITE|LE_B18_NOUFLO;
1778 		break;
1779 	}
1780 	pcn_bcr_write(sc, LE_BCR18, reg);
1781 
1782 	/*
1783 	 * Initialize CSR80 (FIFO thresholds for Tx and Rx).
1784 	 */
1785 	pcn_csr_write(sc, LE_CSR80, LE_C80_RCVFW(sc->sc_rcvfw) |
1786 	    LE_C80_XMTSP(sc->sc_xmtsp) | LE_C80_XMTFW(sc->sc_xmtfw));
1787 
1788 	/*
1789 	 * Send the init block to the chip, and wait for it
1790 	 * to be processed.
1791 	 */
1792 	PCN_CDINITSYNC(sc, BUS_DMASYNC_PREWRITE);
1793 	pcn_csr_write(sc, LE_CSR1, PCN_CDINITADDR(sc) & 0xffff);
1794 	pcn_csr_write(sc, LE_CSR2, (PCN_CDINITADDR(sc) >> 16) & 0xffff);
1795 	pcn_csr_write(sc, LE_CSR0, LE_C0_INIT);
1796 	delay(100);
1797 	for (i = 0; i < 10000; i++) {
1798 		if (pcn_csr_read(sc, LE_CSR0) & LE_C0_IDON)
1799 			break;
1800 		delay(10);
1801 	}
1802 	PCN_CDINITSYNC(sc, BUS_DMASYNC_POSTWRITE);
1803 	if (i == 10000) {
1804 		printf("%s: timeout processing init block\n",
1805 		    device_xname(sc->sc_dev));
1806 		error = EIO;
1807 		goto out;
1808 	}
1809 
1810 	/* Set the media. */
1811 	if ((error = mii_ifmedia_change(&sc->sc_mii)) != 0)
1812 		goto out;
1813 
1814 	/* Enable interrupts and external activity (and ACK IDON). */
1815 	pcn_csr_write(sc, LE_CSR0, LE_C0_INEA|LE_C0_STRT|LE_C0_IDON);
1816 
1817 	if (sc->sc_flags & PCN_F_HAS_MII) {
1818 		/* Start the one second MII clock. */
1819 		callout_reset(&sc->sc_tick_ch, hz, pcn_tick, sc);
1820 	}
1821 
1822 	/* ...all done! */
1823 	ifp->if_flags |= IFF_RUNNING;
1824 	ifp->if_flags &= ~IFF_OACTIVE;
1825 
1826  out:
1827 	if (error)
1828 		printf("%s: interface not running\n", device_xname(sc->sc_dev));
1829 	return (error);
1830 }
1831 
1832 /*
1833  * pcn_rxdrain:
1834  *
1835  *	Drain the receive queue.
1836  */
1837 static void
1838 pcn_rxdrain(struct pcn_softc *sc)
1839 {
1840 	struct pcn_rxsoft *rxs;
1841 	int i;
1842 
1843 	for (i = 0; i < PCN_NRXDESC; i++) {
1844 		rxs = &sc->sc_rxsoft[i];
1845 		if (rxs->rxs_mbuf != NULL) {
1846 			bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1847 			m_freem(rxs->rxs_mbuf);
1848 			rxs->rxs_mbuf = NULL;
1849 		}
1850 	}
1851 }
1852 
1853 /*
1854  * pcn_stop:		[ifnet interface function]
1855  *
1856  *	Stop transmission on the interface.
1857  */
1858 static void
1859 pcn_stop(struct ifnet *ifp, int disable)
1860 {
1861 	struct pcn_softc *sc = ifp->if_softc;
1862 	struct pcn_txsoft *txs;
1863 	int i;
1864 
1865 	if (sc->sc_flags & PCN_F_HAS_MII) {
1866 		/* Stop the one second clock. */
1867 		callout_stop(&sc->sc_tick_ch);
1868 
1869 		/* Down the MII. */
1870 		mii_down(&sc->sc_mii);
1871 	}
1872 
1873 	/* Stop the chip. */
1874 	pcn_csr_write(sc, LE_CSR0, LE_C0_STOP);
1875 
1876 	/* Release any queued transmit buffers. */
1877 	for (i = 0; i < PCN_TXQUEUELEN; i++) {
1878 		txs = &sc->sc_txsoft[i];
1879 		if (txs->txs_mbuf != NULL) {
1880 			bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
1881 			m_freem(txs->txs_mbuf);
1882 			txs->txs_mbuf = NULL;
1883 		}
1884 	}
1885 
1886 	/* Mark the interface as down and cancel the watchdog timer. */
1887 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1888 	ifp->if_timer = 0;
1889 
1890 	if (disable)
1891 		pcn_rxdrain(sc);
1892 }
1893 
1894 /*
1895  * pcn_add_rxbuf:
1896  *
1897  *	Add a receive buffer to the indicated descriptor.
1898  */
1899 static int
1900 pcn_add_rxbuf(struct pcn_softc *sc, int idx)
1901 {
1902 	struct pcn_rxsoft *rxs = &sc->sc_rxsoft[idx];
1903 	struct mbuf *m;
1904 	int error;
1905 
1906 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1907 	if (m == NULL)
1908 		return (ENOBUFS);
1909 
1910 	MCLGET(m, M_DONTWAIT);
1911 	if ((m->m_flags & M_EXT) == 0) {
1912 		m_freem(m);
1913 		return (ENOBUFS);
1914 	}
1915 
1916 	if (rxs->rxs_mbuf != NULL)
1917 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
1918 
1919 	rxs->rxs_mbuf = m;
1920 
1921 	error = bus_dmamap_load(sc->sc_dmat, rxs->rxs_dmamap,
1922 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1923 	    BUS_DMA_READ|BUS_DMA_NOWAIT);
1924 	if (error) {
1925 		printf("%s: can't load rx DMA map %d, error = %d\n",
1926 		    device_xname(sc->sc_dev), idx, error);
1927 		panic("pcn_add_rxbuf");
1928 	}
1929 
1930 	bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
1931 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
1932 
1933 	PCN_INIT_RXDESC(sc, idx);
1934 
1935 	return (0);
1936 }
1937 
1938 /*
1939  * pcn_set_filter:
1940  *
1941  *	Set up the receive filter.
1942  */
1943 static void
1944 pcn_set_filter(struct pcn_softc *sc)
1945 {
1946 	struct ethercom *ec = &sc->sc_ethercom;
1947 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
1948 	struct ether_multi *enm;
1949 	struct ether_multistep step;
1950 	uint32_t crc;
1951 
1952 	/*
1953 	 * Set up the multicast address filter by passing all multicast
1954 	 * addresses through a CRC generator, and then using the high
1955 	 * order 6 bits as an index into the 64-bit logical address
1956 	 * filter.  The high order bits select the word, while the rest
1957 	 * of the bits select the bit within the word.
1958 	 */
1959 
1960 	if (ifp->if_flags & IFF_PROMISC)
1961 		goto allmulti;
1962 
1963 	sc->sc_initblock.init_ladrf[0] =
1964 	    sc->sc_initblock.init_ladrf[1] =
1965 	    sc->sc_initblock.init_ladrf[2] =
1966 	    sc->sc_initblock.init_ladrf[3] = 0;
1967 
1968 	ETHER_FIRST_MULTI(step, ec, enm);
1969 	while (enm != NULL) {
1970 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
1971 			/*
1972 			 * We must listen to a range of multicast addresses.
1973 			 * For now, just accept all multicasts, rather than
1974 			 * trying to set only those filter bits needed to match
1975 			 * the range.  (At this time, the only use of address
1976 			 * ranges is for IP multicast routing, for which the
1977 			 * range is big enough to require all bits set.)
1978 			 */
1979 			goto allmulti;
1980 		}
1981 
1982 		crc = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN);
1983 
1984 		/* Just want the 6 most significant bits. */
1985 		crc >>= 26;
1986 
1987 		/* Set the corresponding bit in the filter. */
1988 		sc->sc_initblock.init_ladrf[crc >> 4] |=
1989 		    htole16(1 << (crc & 0xf));
1990 
1991 		ETHER_NEXT_MULTI(step, enm);
1992 	}
1993 
1994 	ifp->if_flags &= ~IFF_ALLMULTI;
1995 	return;
1996 
1997  allmulti:
1998 	ifp->if_flags |= IFF_ALLMULTI;
1999 	sc->sc_initblock.init_ladrf[0] =
2000 	    sc->sc_initblock.init_ladrf[1] =
2001 	    sc->sc_initblock.init_ladrf[2] =
2002 	    sc->sc_initblock.init_ladrf[3] = 0xffff;
2003 }
2004 
2005 /*
2006  * pcn_79c970_mediainit:
2007  *
2008  *	Initialize media for the Am79c970.
2009  */
2010 static void
2011 pcn_79c970_mediainit(struct pcn_softc *sc)
2012 {
2013 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
2014 	const char *sep = "";
2015 
2016 	sc->sc_mii.mii_ifp = ifp;
2017 
2018 	ifmedia_init(&sc->sc_mii.mii_media, IFM_IMASK, pcn_79c970_mediachange,
2019 	    pcn_79c970_mediastatus);
2020 
2021 #define	ADD(str, m, d)							\
2022 do {									\
2023 	aprint_normal("%s%s", sep, str);					\
2024 	ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|(m), (d), NULL);	\
2025 	sep = ", ";							\
2026 } while (/*CONSTCOND*/0)
2027 
2028 	aprint_normal("%s: ", device_xname(sc->sc_dev));
2029 	ADD("10base5", IFM_10_5, PORTSEL_AUI);
2030 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
2031 		ADD("10base5-FDX", IFM_10_5|IFM_FDX, PORTSEL_AUI);
2032 	ADD("10baseT", IFM_10_T, PORTSEL_10T);
2033 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
2034 		ADD("10baseT-FDX", IFM_10_T|IFM_FDX, PORTSEL_10T);
2035 	ADD("auto", IFM_AUTO, 0);
2036 	if (sc->sc_variant->pcv_chipid == PARTID_Am79c970A)
2037 		ADD("auto-FDX", IFM_AUTO|IFM_FDX, 0);
2038 	aprint_normal("\n");
2039 
2040 	ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
2041 }
2042 
2043 /*
2044  * pcn_79c970_mediastatus:	[ifmedia interface function]
2045  *
2046  *	Get the current interface media status (Am79c970 version).
2047  */
2048 static void
2049 pcn_79c970_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
2050 {
2051 	struct pcn_softc *sc = ifp->if_softc;
2052 
2053 	/*
2054 	 * The currently selected media is always the active media.
2055 	 * Note: We have no way to determine what media the AUTO
2056 	 * process picked.
2057 	 */
2058 	ifmr->ifm_active = sc->sc_mii.mii_media.ifm_media;
2059 }
2060 
2061 /*
2062  * pcn_79c970_mediachange:	[ifmedia interface function]
2063  *
2064  *	Set hardware to newly-selected media (Am79c970 version).
2065  */
2066 static int
2067 pcn_79c970_mediachange(struct ifnet *ifp)
2068 {
2069 	struct pcn_softc *sc = ifp->if_softc;
2070 	uint32_t reg;
2071 
2072 	if (IFM_SUBTYPE(sc->sc_mii.mii_media.ifm_media) == IFM_AUTO) {
2073 		/*
2074 		 * CSR15:PORTSEL doesn't matter.  Just set BCR2:ASEL.
2075 		 */
2076 		reg = pcn_bcr_read(sc, LE_BCR2);
2077 		reg |= LE_B2_ASEL;
2078 		pcn_bcr_write(sc, LE_BCR2, reg);
2079 	} else {
2080 		/*
2081 		 * Clear BCR2:ASEL and set the new CSR15:PORTSEL value.
2082 		 */
2083 		reg = pcn_bcr_read(sc, LE_BCR2);
2084 		reg &= ~LE_B2_ASEL;
2085 		pcn_bcr_write(sc, LE_BCR2, reg);
2086 
2087 		reg = pcn_csr_read(sc, LE_CSR15);
2088 		reg = (reg & ~LE_C15_PORTSEL(PORTSEL_MASK)) |
2089 		    LE_C15_PORTSEL(sc->sc_mii.mii_media.ifm_cur->ifm_data);
2090 		pcn_csr_write(sc, LE_CSR15, reg);
2091 	}
2092 
2093 	if ((sc->sc_mii.mii_media.ifm_media & IFM_FDX) != 0) {
2094 		reg = LE_B9_FDEN;
2095 		if (IFM_SUBTYPE(sc->sc_mii.mii_media.ifm_media) == IFM_10_5)
2096 			reg |= LE_B9_AUIFD;
2097 		pcn_bcr_write(sc, LE_BCR9, reg);
2098 	} else
2099 		pcn_bcr_write(sc, LE_BCR9, 0);
2100 
2101 	return (0);
2102 }
2103 
2104 /*
2105  * pcn_79c971_mediainit:
2106  *
2107  *	Initialize media for the Am79c971.
2108  */
2109 static void
2110 pcn_79c971_mediainit(struct pcn_softc *sc)
2111 {
2112 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
2113 
2114 	/* We have MII. */
2115 	sc->sc_flags |= PCN_F_HAS_MII;
2116 
2117 	/*
2118 	 * The built-in 10BASE-T interface is mapped to the MII
2119 	 * on the PCNet-FAST.  Unfortunately, there's no EEPROM
2120 	 * word that tells us which PHY to use.
2121 	 * This driver used to ignore all but the first PHY to
2122 	 * answer, but this code was removed to support multiple
2123 	 * external PHYs. As the default instance will be the first
2124 	 * one to answer, no harm is done by letting the possibly
2125 	 * non-connected internal PHY show up.
2126 	 */
2127 
2128 	/* Initialize our media structures and probe the MII. */
2129 	sc->sc_mii.mii_ifp = ifp;
2130 	sc->sc_mii.mii_readreg = pcn_mii_readreg;
2131 	sc->sc_mii.mii_writereg = pcn_mii_writereg;
2132 	sc->sc_mii.mii_statchg = pcn_mii_statchg;
2133 
2134 	sc->sc_ethercom.ec_mii = &sc->sc_mii;
2135 	ifmedia_init(&sc->sc_mii.mii_media, 0, ether_mediachange,
2136 	    ether_mediastatus);
2137 
2138 	mii_attach(sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
2139 	    MII_OFFSET_ANY, 0);
2140 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
2141 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
2142 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
2143 	} else
2144 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
2145 }
2146 
2147 /*
2148  * pcn_mii_readreg:	[mii interface function]
2149  *
2150  *	Read a PHY register on the MII.
2151  */
2152 static int
2153 pcn_mii_readreg(device_t self, int phy, int reg)
2154 {
2155 	struct pcn_softc *sc = device_private(self);
2156 	uint32_t rv;
2157 
2158 	pcn_bcr_write(sc, LE_BCR33, reg | (phy << PHYAD_SHIFT));
2159 	rv = pcn_bcr_read(sc, LE_BCR34) & LE_B34_MIIMD;
2160 	if (rv == 0xffff)
2161 		return (0);
2162 
2163 	return (rv);
2164 }
2165 
2166 /*
2167  * pcn_mii_writereg:	[mii interface function]
2168  *
2169  *	Write a PHY register on the MII.
2170  */
2171 static void
2172 pcn_mii_writereg(device_t self, int phy, int reg, int val)
2173 {
2174 	struct pcn_softc *sc = device_private(self);
2175 
2176 	pcn_bcr_write(sc, LE_BCR33, reg | (phy << PHYAD_SHIFT));
2177 	pcn_bcr_write(sc, LE_BCR34, val);
2178 }
2179 
2180 /*
2181  * pcn_mii_statchg:	[mii interface function]
2182  *
2183  *	Callback from MII layer when media changes.
2184  */
2185 static void
2186 pcn_mii_statchg(struct ifnet *ifp)
2187 {
2188 	struct pcn_softc *sc = ifp->if_softc;
2189 
2190 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0)
2191 		pcn_bcr_write(sc, LE_BCR9, LE_B9_FDEN);
2192 	else
2193 		pcn_bcr_write(sc, LE_BCR9, 0);
2194 }
2195