xref: /netbsd-src/sys/arch/mips/alchemy/dev/if_aumac.c (revision 4b896b232495b7a9b8b94a1cf1e21873296d53b8)
1 /* $NetBSD: if_aumac.c,v 1.11 2003/07/04 01:19:58 thorpej 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 Alchemy Semiconductor Au1x00 Ethernet Media
40  * Access Controller.
41  *
42  * TODO:
43  *
44  *	Better Rx buffer management; we want to get new Rx buffers
45  *	to the chip more quickly than we currently do.
46  */
47 
48 #include <sys/cdefs.h>
49 __KERNEL_RCSID(0, "$NetBSD: if_aumac.c,v 1.11 2003/07/04 01:19:58 thorpej Exp $");
50 
51 #include "bpfilter.h"
52 
53 #include <sys/param.h>
54 #include <sys/systm.h>
55 #include <sys/callout.h>
56 #include <sys/mbuf.h>
57 #include <sys/malloc.h>
58 #include <sys/kernel.h>
59 #include <sys/socket.h>
60 #include <sys/ioctl.h>
61 #include <sys/errno.h>
62 #include <sys/device.h>
63 #include <sys/queue.h>
64 
65 #include <uvm/uvm_extern.h>		/* for PAGE_SIZE */
66 
67 #include <net/if.h>
68 #include <net/if_dl.h>
69 #include <net/if_media.h>
70 #include <net/if_ether.h>
71 
72 #if NBPFILTER > 0
73 #include <net/bpf.h>
74 #endif
75 
76 #include <machine/bus.h>
77 #include <machine/intr.h>
78 #include <machine/endian.h>
79 
80 #include <dev/mii/mii.h>
81 #include <dev/mii/miivar.h>
82 
83 #include <mips/alchemy/include/aureg.h>
84 #include <mips/alchemy/include/auvar.h>
85 #include <mips/alchemy/include/aubusvar.h>
86 #include <mips/alchemy/dev/if_aumacreg.h>
87 
88 /*
89  * The Au1X00 MAC has 4 transmit and receive descriptors.  Each buffer
90  * must consist of a single DMA segment, and must be aligned to a 2K
91  * boundary.  Therefore, this driver does not perform DMA directly
92  * to/from mbufs.  Instead, we copy the data to/from buffers allocated
93  * at device attach time.
94  *
95  * We also skip the bus_dma dance.  The MAC is built in to the CPU, so
96  * there's little point in not making assumptions based on the CPU type.
97  * We also program the Au1X00 cache to be DMA coherent, so the buffers
98  * are accessed via KSEG0 addresses.
99  */
100 #define	AUMAC_NTXDESC		4
101 #define	AUMAC_NTXDESC_MASK	(AUMAC_NTXDESC - 1)
102 
103 #define	AUMAC_NRXDESC		4
104 #define	AUMAC_NRXDESC_MASK	(AUMAC_NRXDESC - 1)
105 
106 #define	AUMAC_NEXTTX(x)		(((x) + 1) & AUMAC_NTXDESC_MASK)
107 #define	AUMAC_NEXTRX(x)		(((x) + 1) & AUMAC_NRXDESC_MASK)
108 
109 #define	AUMAC_TXBUF_OFFSET	0
110 #define	AUMAC_RXBUF_OFFSET	(MAC_BUFLEN * AUMAC_NTXDESC)
111 #define	AUMAC_BUFSIZE		(MAC_BUFLEN * (AUMAC_NTXDESC + AUMAC_NRXDESC))
112 
113 struct aumac_buf {
114 	caddr_t buf_vaddr;		/* virtual address of buffer */
115 	bus_addr_t buf_paddr;		/* DMA address of buffer */
116 };
117 
118 /*
119  * Software state per device.
120  */
121 struct aumac_softc {
122 	struct device sc_dev;		/* generic device information */
123 	bus_space_tag_t sc_st;		/* bus space tag */
124 	bus_space_handle_t sc_mac_sh;	/* MAC space handle */
125 	bus_space_handle_t sc_macen_sh;	/* MAC enable space handle */
126 	bus_space_handle_t sc_dma_sh;	/* DMA space handle */
127 	struct ethercom sc_ethercom;	/* Ethernet common data */
128 	void *sc_sdhook;		/* shutdown hook */
129 
130 	void *sc_ih;			/* interrupt cookie */
131 
132 	struct mii_data sc_mii;		/* MII/media information */
133 
134 	struct callout sc_tick_ch;	/* tick callout */
135 
136 	/* Transmit and receive buffers */
137 	struct aumac_buf sc_txbufs[AUMAC_NTXDESC];
138 	struct aumac_buf sc_rxbufs[AUMAC_NRXDESC];
139 	caddr_t sc_bufaddr;
140 
141 	int sc_txfree;			/* number of free Tx descriptors */
142 	int sc_txnext;			/* next Tx descriptor to use */
143 	int sc_txdirty;			/* first dirty Tx descriptor */
144 
145 	int sc_rxptr;			/* next ready Rx descriptor */
146 
147 #ifdef AUMAC_EVENT_COUNTERS
148 	struct evcnt sc_ev_txstall;	/* Tx stalled */
149 	struct evcnt sc_ev_rxstall;	/* Rx stalled */
150 	struct evcnt sc_ev_txintr;	/* Tx interrupts */
151 	struct evcnt sc_ev_rxintr;	/* Rx interrupts */
152 #endif
153 
154 	uint32_t sc_control;		/* MAC_CONTROL contents */
155 	uint32_t sc_flowctrl;		/* MAC_FLOWCTRL contents */
156 };
157 
158 #ifdef AUMAC_EVENT_COUNTERS
159 #define	AUMAC_EVCNT_INCR(ev)	(ev)->ev_count++
160 #else
161 #define	AUMAC_EVCNT_INCR(ev)	/* nothing */
162 #endif
163 
164 #define	AUMAC_INIT_RXDESC(sc, x)					\
165 do {									\
166 	bus_space_write_4((sc)->sc_st, (sc)->sc_dma_sh,			\
167 	    MACDMA_RX_STAT((x)), 0);					\
168 	bus_space_write_4((sc)->sc_st, (sc)->sc_dma_sh,			\
169 	    MACDMA_RX_ADDR((x)),					\
170 	    (sc)->sc_rxbufs[(x)].buf_paddr | RX_ADDR_EN);		\
171 } while (/*CONSTCOND*/0)
172 
173 static void	aumac_start(struct ifnet *);
174 static void	aumac_watchdog(struct ifnet *);
175 static int	aumac_ioctl(struct ifnet *, u_long, caddr_t);
176 static int	aumac_init(struct ifnet *);
177 static void	aumac_stop(struct ifnet *, int);
178 
179 static void	aumac_shutdown(void *);
180 
181 static void	aumac_tick(void *);
182 
183 static void	aumac_set_filter(struct aumac_softc *);
184 
185 static void	aumac_powerup(struct aumac_softc *);
186 static void	aumac_powerdown(struct aumac_softc *);
187 
188 static int	aumac_intr(void *);
189 static void	aumac_txintr(struct aumac_softc *);
190 static void	aumac_rxintr(struct aumac_softc *);
191 
192 static int	aumac_mii_readreg(struct device *, int, int);
193 static void	aumac_mii_writereg(struct device *, int, int, int);
194 static void	aumac_mii_statchg(struct device *);
195 static int	aumac_mii_wait(struct aumac_softc *, const char *);
196 
197 static int	aumac_mediachange(struct ifnet *);
198 static void	aumac_mediastatus(struct ifnet *, struct ifmediareq *);
199 
200 static int	aumac_match(struct device *, struct cfdata *, void *);
201 static void	aumac_attach(struct device *, struct device *, void *);
202 
203 int	aumac_copy_small = 0;
204 
205 CFATTACH_DECL(aumac, sizeof(struct aumac_softc),
206     aumac_match, aumac_attach, NULL, NULL);
207 
208 static int
209 aumac_match(struct device *parent, struct cfdata *cf, void *aux)
210 {
211 	struct aubus_attach_args *aa = aux;
212 
213 	if (strcmp(aa->aa_name, cf->cf_name) == 0)
214 		return (1);
215 
216 	return (0);
217 }
218 
219 static void
220 aumac_attach(struct device *parent, struct device *self, void *aux)
221 {
222 	uint8_t enaddr[ETHER_ADDR_LEN];
223 	struct aumac_softc *sc = (void *) self;
224 	struct aubus_attach_args *aa = aux;
225 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
226 	struct pglist pglist;
227 	paddr_t bufaddr;
228 	caddr_t vbufaddr;
229 	int i;
230 
231 	callout_init(&sc->sc_tick_ch);
232 
233 	printf(": Au1X00 10/100 Ethernet\n");
234 
235 	sc->sc_st = aa->aa_st;
236 
237 	/* Get the MAC address. */
238 	if (prop_get(dev_propdb, &sc->sc_dev, "mac-addr", enaddr,
239 		     sizeof(enaddr), NULL) != sizeof(enaddr)) {
240 		printf("%s: unable to get mac-addr property\n",
241 		    sc->sc_dev.dv_xname);
242 		return;
243 	}
244 
245 	printf("%s: Ethernet address %s\n", sc->sc_dev.dv_xname,
246 	    ether_sprintf(enaddr));
247 
248 	/* Map the device. */
249 	if (bus_space_map(sc->sc_st, aa->aa_addrs[AA_MAC_BASE],
250 	    MACx_SIZE, 0, &sc->sc_mac_sh) != 0) {
251 		printf("%s: unable to map MAC registers\n",
252 		    sc->sc_dev.dv_xname);
253 		return;
254 	}
255 	if (bus_space_map(sc->sc_st, aa->aa_addrs[AA_MAC_ENABLE],
256 	    MACENx_SIZE, 0, &sc->sc_macen_sh) != 0) {
257 		printf("%s: unable to map MACEN registers\n",
258 		    sc->sc_dev.dv_xname);
259 		return;
260 	}
261 	if (bus_space_map(sc->sc_st, aa->aa_addrs[AA_MAC_DMA_BASE],
262 	    MACx_DMA_SIZE, 0, &sc->sc_dma_sh) != 0) {
263 		printf("%s: unable to map MACDMA registers\n",
264 		    sc->sc_dev.dv_xname);
265 		return;
266 	}
267 
268 	/* Make sure the MAC is powered off. */
269 	aumac_powerdown(sc);
270 
271 	/* Hook up the interrupt handler. */
272 	sc->sc_ih = au_intr_establish(aa->aa_irq[0], 1, IPL_NET, IST_LEVEL,
273 	    aumac_intr, sc);
274 	if (sc->sc_ih == NULL) {
275 		printf("%s: unable to register interrupt handler\n",
276 		    sc->sc_dev.dv_xname);
277 		return;
278 	}
279 
280 	/*
281 	 * Allocate space for the transmit and receive buffers.
282 	 */
283 	if (uvm_pglistalloc(AUMAC_BUFSIZE, 0, ctob(physmem), PAGE_SIZE, 0,
284 	    &pglist, 1, 0))
285 		return;
286 
287 	bufaddr = TAILQ_FIRST(&pglist)->phys_addr;
288 	vbufaddr = (void *)MIPS_PHYS_TO_KSEG0(bufaddr);
289 
290 	for (i = 0; i < AUMAC_NTXDESC; i++) {
291 		int offset = AUMAC_TXBUF_OFFSET + (i * MAC_BUFLEN);
292 
293 		sc->sc_txbufs[i].buf_vaddr = vbufaddr + offset;
294 		sc->sc_txbufs[i].buf_paddr = bufaddr + offset;
295 	}
296 
297 	for (i = 0; i < AUMAC_NRXDESC; i++) {
298 		int offset = AUMAC_RXBUF_OFFSET + (i * MAC_BUFLEN);
299 
300 		sc->sc_rxbufs[i].buf_vaddr = vbufaddr + offset;
301 		sc->sc_rxbufs[i].buf_paddr = bufaddr + offset;
302 	}
303 
304 	/*
305 	 * Power up the MAC before accessing any MAC registers (including
306 	 * MII configuration.
307 	 */
308 	aumac_powerup(sc);
309 
310 	/*
311 	 * Initialize the media structures and probe the MII.
312 	 */
313 	sc->sc_mii.mii_ifp = ifp;
314 	sc->sc_mii.mii_readreg = aumac_mii_readreg;
315 	sc->sc_mii.mii_writereg = aumac_mii_writereg;
316 	sc->sc_mii.mii_statchg = aumac_mii_statchg;
317 	ifmedia_init(&sc->sc_mii.mii_media, 0, aumac_mediachange,
318 	    aumac_mediastatus);
319 
320 	mii_attach(&sc->sc_dev, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
321 	    MII_OFFSET_ANY, 0);
322 
323 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
324 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
325 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_NONE);
326 	} else
327 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER|IFM_AUTO);
328 
329 	strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
330 	ifp->if_softc = sc;
331 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
332 	ifp->if_ioctl = aumac_ioctl;
333 	ifp->if_start = aumac_start;
334 	ifp->if_watchdog = aumac_watchdog;
335 	ifp->if_init = aumac_init;
336 	ifp->if_stop = aumac_stop;
337 	IFQ_SET_READY(&ifp->if_snd);
338 
339 	/* Attach the interface. */
340 	if_attach(ifp);
341 	ether_ifattach(ifp, enaddr);
342 
343 #ifdef AUMAC_EVENT_COUNTERS
344 	evcnt_attach_dynamic(&sc->sc_ev_txstall, EVCNT_TYPE_MISC,
345 	    NULL, sc->sc_dev.dv_xname, "txstall");
346 	evcnt_attach_dynamic(&sc->sc_ev_rxstall, EVCNT_TYPE_MISC,
347 	    NULL, sc->sc_dev.dv_xname, "rxstall");
348 	evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_MISC,
349 	    NULL, sc->sc_dev.dv_xname, "txintr");
350 	evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_MISC,
351 	    NULL, sc->sc_dev.dv_xname, "rxintr");
352 #endif
353 
354 	/* Make sure the interface is shutdown during reboot. */
355 	sc->sc_sdhook = shutdownhook_establish(aumac_shutdown, sc);
356 	if (sc->sc_sdhook == NULL)
357 		printf("%s: WARNING: unable to establish shutdown hook\n",
358 		    sc->sc_dev.dv_xname);
359 	return;
360 }
361 
362 /*
363  * aumac_shutdown:
364  *
365  *	Make sure the interface is stopped at reboot time.
366  */
367 static void
368 aumac_shutdown(void *arg)
369 {
370 	struct aumac_softc *sc = arg;
371 
372 	aumac_stop(&sc->sc_ethercom.ec_if, 1);
373 
374 	/*
375 	 * XXX aumac_stop leaves device powered up at the moment
376 	 * XXX but this still isn't enough to keep yamon happy... :-(
377 	 */
378 	bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0, 0);
379 }
380 
381 /*
382  * aumac_start:		[ifnet interface function]
383  *
384  *	Start packet transmission on the interface.
385  */
386 static void
387 aumac_start(struct ifnet *ifp)
388 {
389 	struct aumac_softc *sc = ifp->if_softc;
390 	struct mbuf *m;
391 	int nexttx;
392 
393 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
394 		return;
395 
396 	/*
397 	 * Loop through the send queue, setting up transmit descriptors
398 	 * unitl we drain the queue, or use up all available transmit
399 	 * descriptors.
400 	 */
401 	for (;;) {
402 		/* Grab a packet off the queue. */
403 		IFQ_POLL(&ifp->if_snd, m);
404 		if (m == NULL)
405 			return;
406 
407 		/* Get a spare descriptor. */
408 		if (sc->sc_txfree == 0) {
409 			/* No more slots left; notify upper layer. */
410 			ifp->if_flags |= IFF_OACTIVE;
411 			AUMAC_EVCNT_INCR(&sc->sc_ev_txstall);
412 			return;
413 		}
414 		nexttx = sc->sc_txnext;
415 
416 		IFQ_DEQUEUE(&ifp->if_snd, m);
417 
418 		/*
419 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
420 		 */
421 
422 		m_copydata(m, 0, m->m_pkthdr.len,
423 		    sc->sc_txbufs[nexttx].buf_vaddr);
424 
425 		/* Zero out the remainder of any short packets. */
426 		if (m->m_pkthdr.len < (ETHER_MIN_LEN - ETHER_CRC_LEN))
427 			memset(sc->sc_txbufs[nexttx].buf_vaddr +
428 			    m->m_pkthdr.len, 0,
429 			    ETHER_MIN_LEN - ETHER_CRC_LEN - m->m_pkthdr.len);
430 
431 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
432 		    MACDMA_TX_STAT(nexttx), 0);
433 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
434 		    MACDMA_TX_LEN(nexttx),
435 		    m->m_pkthdr.len < (ETHER_MIN_LEN - ETHER_CRC_LEN) ?
436 		    ETHER_MIN_LEN - ETHER_CRC_LEN : m->m_pkthdr.len);
437 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
438 		    MACDMA_TX_ADDR(nexttx),
439 		    sc->sc_txbufs[nexttx].buf_paddr | TX_ADDR_EN);
440 		/* XXX - needed??  we should be coherent */
441 		bus_space_barrier(sc->sc_st, sc->sc_dma_sh, 0 /* XXX */,
442 		    0 /* XXX */, BUS_SPACE_BARRIER_WRITE);
443 
444 		/* Advance the Tx pointer. */
445 		sc->sc_txfree--;
446 		sc->sc_txnext = AUMAC_NEXTTX(nexttx);
447 
448 #if NBPFILTER > 0
449 		/* Pass the packet to any BPF listeners. */
450 		if (ifp->if_bpf)
451 			bpf_mtap(ifp->if_bpf, m);
452 #endif /* NBPFILTER */
453 
454 		m_freem(m);
455 
456 		/* Set a watchdog timer in case the chip flakes out. */
457 		ifp->if_timer = 5;
458 	}
459 	/* NOTREACHED */
460 }
461 
462 /*
463  * aumac_watchdog:	[ifnet interface function]
464  *
465  *	Watchdog timer handler.
466  */
467 static void
468 aumac_watchdog(struct ifnet *ifp)
469 {
470 	struct aumac_softc *sc = ifp->if_softc;
471 
472 	printf("%s: device timeout\n", sc->sc_dev.dv_xname);
473 	(void) aumac_init(ifp);
474 
475 	/* Try to get more packets going. */
476 	aumac_start(ifp);
477 }
478 
479 /*
480  * aumac_ioctl:		[ifnet interface function]
481  *
482  *	Handle control requests from the operator.
483  */
484 static int
485 aumac_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
486 {
487 	struct aumac_softc *sc = ifp->if_softc;
488 	struct ifreq *ifr = (struct ifreq *) data;
489 	int s, error;
490 
491 	s = splnet();
492 
493 	switch (cmd) {
494 	case SIOCSIFMEDIA:
495 	case SIOCGIFMEDIA:
496 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, cmd);
497 		break;
498 
499 	default:
500 		error = ether_ioctl(ifp, cmd, data);
501 		if (error == ENETRESET) {
502 			/*
503 			 * Multicast list has changed; set the hardware filter
504 			 * accordingly.
505 			 */
506 			aumac_set_filter(sc);
507 		}
508 		break;
509 	}
510 
511 	/* Try to get more packets going. */
512 	aumac_start(ifp);
513 
514 	splx(s);
515 	return (error);
516 }
517 
518 /*
519  * aumac_intr:
520  *
521  *	Interrupt service routine.
522  */
523 static int
524 aumac_intr(void *arg)
525 {
526 	struct aumac_softc *sc = arg;
527 
528 	/*
529 	 * There aren't really any interrupt status bits on the
530 	 * Au1X00 MAC, and each MAC has a dedicated interrupt
531 	 * in the CPU's built-in interrupt controller.  Just
532 	 * check for new incoming packets, and then Tx completions
533 	 * (for status updating).
534 	 */
535 	if ((sc->sc_ethercom.ec_if.if_flags & IFF_RUNNING) == 0)
536 		return (0);
537 
538 	aumac_rxintr(sc);
539 	aumac_txintr(sc);
540 
541 	return (1);
542 }
543 
544 /*
545  * aumac_txintr:
546  *
547  *	Helper; handle transmit interrupts.
548  */
549 static void
550 aumac_txintr(struct aumac_softc *sc)
551 {
552 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
553 	uint32_t stat;
554 	int i;
555 #ifdef AUMAC_EVENT_COUNTERS
556 	int gotone = 0;
557 #endif
558 
559 	for (i = sc->sc_txdirty; sc->sc_txfree != AUMAC_NTXDESC;
560 	     i = AUMAC_NEXTTX(i)) {
561 		if ((bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
562 		     MACDMA_TX_ADDR(i)) & TX_ADDR_DN) == 0)
563 			break;
564 #ifdef AUMAC_EVENT_COUNTERS
565 		gotone = 1;
566 #endif
567 
568 		/* ACK interrupt. */
569 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
570 		    MACDMA_TX_ADDR(i), 0);
571 
572 		stat = bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
573 		    MACDMA_TX_STAT(i));
574 
575 		if (stat & TX_STAT_FA) {
576 			/* XXX STATS */
577 			ifp->if_oerrors++;
578 		} else
579 			ifp->if_opackets++;
580 
581 		if (stat & TX_STAT_EC)
582 			ifp->if_collisions += 16;
583 		else
584 			ifp->if_collisions += TX_STAT_CC(stat);
585 
586 		sc->sc_txfree++;
587 		ifp->if_flags &= ~IFF_OACTIVE;
588 
589 		/* Try to queue more packets. */
590 		aumac_start(ifp);
591 	}
592 
593 	if (gotone)
594 		AUMAC_EVCNT_INCR(&sc->sc_ev_txintr);
595 
596 	/* Update the dirty descriptor pointer. */
597 	sc->sc_txdirty = i;
598 
599 	/*
600 	 * If there are no more pending transmissions, cancel the watchdog
601 	 * timer.
602 	 */
603 	if (sc->sc_txfree == AUMAC_NTXDESC)
604 		ifp->if_timer = 0;
605 }
606 
607 /*
608  * aumac_rxintr:
609  *
610  *	Helper; handle receive interrupts.
611  */
612 static void
613 aumac_rxintr(struct aumac_softc *sc)
614 {
615 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
616 	struct mbuf *m;
617 	uint32_t stat;
618 	int i, len;
619 #ifdef AUMAC_EVENT_COUNTERS
620 	int pkts = 0;
621 #endif
622 
623 	for (i = sc->sc_rxptr;; i = AUMAC_NEXTRX(i)) {
624 		if ((bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
625 		     MACDMA_RX_ADDR(i)) & RX_ADDR_DN) == 0)
626 			break;
627 #ifdef AUMAC_EVENT_COUNTERS
628 		pkts++;
629 #endif
630 
631 		stat = bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
632 		    MACDMA_RX_STAT(i));
633 
634 #define PRINTERR(str)							\
635 	do {								\
636 		error++;						\
637 		printf("%s: %s\n", sc->sc_dev.dv_xname, str);		\
638 	} while (0)
639 
640 		if (stat & RX_STAT_ERRS) {
641 			int error = 0;
642 
643 			if (stat & RX_STAT_MI)
644 				PRINTERR("missed frame");
645 			if (stat & RX_STAT_UC)
646 				PRINTERR("unknown control frame");
647 			if (stat & RX_STAT_LE)
648 				PRINTERR("short frame");
649 			if (stat & RX_STAT_CR)
650 				PRINTERR("CRC error");
651 			if (stat & RX_STAT_ME)
652 				PRINTERR("medium error");
653 			if (stat & RX_STAT_CS)
654 				PRINTERR("late collision");
655 			if (stat & RX_STAT_FL)
656 				PRINTERR("frame too big");
657 			if (stat & RX_STAT_RF)
658 				PRINTERR("runt frame (collision)");
659 			if (stat & RX_STAT_WT)
660 				PRINTERR("watch dog");
661 			if (stat & RX_STAT_DB) {
662 				if (stat & (RX_STAT_CS | RX_STAT_RF |
663 				    RX_STAT_CR)) {
664 					if (!error)
665 						goto pktok;
666 				} else
667 					PRINTERR("dribbling bit");
668 			}
669 #undef PRINTERR
670 			ifp->if_ierrors++;
671 
672  dropit:
673 			/* reuse the current descriptor */
674 			AUMAC_INIT_RXDESC(sc, i);
675 			continue;
676 		}
677  pktok:
678 		len = RX_STAT_L(stat);
679 
680 		/*
681 		 * The Au1X00 MAC includes the CRC with every packet;
682 		 * trim it off here.
683 		 */
684 		len -= ETHER_CRC_LEN;
685 
686 		/*
687 		 * Truncate the packet if it's too big to fit in
688 		 * a single mbuf cluster.
689 		 */
690 		if (len > MCLBYTES - 2)
691 			len = MCLBYTES - 2;
692 
693 		MGETHDR(m, M_DONTWAIT, MT_DATA);
694 		if (m == NULL) {
695 			printf("%s: unable to allocate Rx mbuf\n",
696 			    sc->sc_dev.dv_xname);
697 			goto dropit;
698 		}
699 		if (len > MHLEN - 2) {
700 			MCLGET(m, M_DONTWAIT);
701 			if ((m->m_flags & M_EXT) == 0) {
702 				printf("%s: unable to allocate Rx cluster\n",
703 				    sc->sc_dev.dv_xname);
704 				m_freem(m);
705 				goto dropit;
706 			}
707 		}
708 
709 		m->m_data += 2;		/* align payload */
710 		memcpy(mtod(m, caddr_t),
711 		    sc->sc_rxbufs[i].buf_vaddr, len);
712 		AUMAC_INIT_RXDESC(sc, i);
713 
714 		m->m_pkthdr.rcvif = ifp;
715 		m->m_pkthdr.len = m->m_len = len;
716 
717 #if NBPFILTER > 0
718 		/* Pass this up to any BPF listeners. */
719 		if (ifp->if_bpf)
720 			bpf_mtap(ifp->if_bpf, m);
721 #endif /* NBPFILTER > 0 */
722 
723 		/* Pass it on. */
724 		(*ifp->if_input)(ifp, m);
725 		ifp->if_ipackets++;
726 	}
727 	if (pkts)
728 		AUMAC_EVCNT_INCR(&sc->sc_ev_rxintr);
729 	if (pkts == AUMAC_NRXDESC)
730 		AUMAC_EVCNT_INCR(&sc->sc_ev_rxstall);
731 
732 	/* Update the receive pointer. */
733 	sc->sc_rxptr = i;
734 }
735 
736 /*
737  * aumac_tick:
738  *
739  *	One second timer, used to tick the MII.
740  */
741 static void
742 aumac_tick(void *arg)
743 {
744 	struct aumac_softc *sc = arg;
745 	int s;
746 
747 	s = splnet();
748 	mii_tick(&sc->sc_mii);
749 	splx(s);
750 
751 	callout_reset(&sc->sc_tick_ch, hz, aumac_tick, sc);
752 }
753 
754 /*
755  * aumac_init:		[ifnet interface function]
756  *
757  *	Initialize the interface.  Must be called at splnet().
758  */
759 static int
760 aumac_init(struct ifnet *ifp)
761 {
762 	struct aumac_softc *sc = ifp->if_softc;
763 	int i, error = 0;
764 
765 	/* Cancel any pending I/O, reset MAC. */
766 	aumac_stop(ifp, 0);
767 
768 	/* Set up the transmit ring. */
769 	for (i = 0; i < AUMAC_NTXDESC; i++) {
770 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
771 		    MACDMA_TX_STAT(i), 0);
772 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
773 		    MACDMA_TX_LEN(i), 0);
774 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
775 		    MACDMA_TX_ADDR(i), sc->sc_txbufs[i].buf_paddr);
776 	}
777 	sc->sc_txfree = AUMAC_NTXDESC;
778 	sc->sc_txnext = TX_ADDR_CB(bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
779 	    MACDMA_TX_ADDR(0)));
780 	sc->sc_txdirty = sc->sc_txnext;
781 
782 	/* Set up the receive ring. */
783 	for (i = 0; i < AUMAC_NRXDESC; i++)
784 			AUMAC_INIT_RXDESC(sc, i);
785 	sc->sc_rxptr = RX_ADDR_CB(bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
786 	    MACDMA_RX_ADDR(0)));
787 
788 	/*
789 	 * Power up the MAC.
790 	 */
791 	aumac_powerup(sc);
792 
793 	sc->sc_control |= CONTROL_DO | CONTROL_TE | CONTROL_RE;
794 #if _BYTE_ORDER == _BIG_ENDIAN
795 	sc->sc_control |= CONTROL_EM;
796 #endif
797 
798 	/* Set the media. */
799 	aumac_mediachange(ifp);
800 
801 	/*
802 	 * Set the receive filter.  This will actually start the transmit
803 	 * and receive processes.
804 	 */
805 	aumac_set_filter(sc);
806 
807 	/* Start the one second clock. */
808 	callout_reset(&sc->sc_tick_ch, hz, aumac_tick, sc);
809 
810 	/* ...all done! */
811 	ifp->if_flags |= IFF_RUNNING;
812 	ifp->if_flags &= ~IFF_OACTIVE;
813 
814 	if (error)
815 		printf("%s: interface not running\n", sc->sc_dev.dv_xname);
816 	return (error);
817 }
818 
819 /*
820  * aumac_stop:		[ifnet interface function]
821  *
822  *	Stop transmission on the interface.
823  */
824 static void
825 aumac_stop(struct ifnet *ifp, int disable)
826 {
827 	struct aumac_softc *sc = ifp->if_softc;
828 
829 	/* Stop the one-second clock. */
830 	callout_stop(&sc->sc_tick_ch);
831 
832 	/* Down the MII. */
833 	mii_down(&sc->sc_mii);
834 
835 	/* Stop the transmit and receive processes. */
836 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL, 0);
837 
838 	/* Power down/reset the MAC. */
839 	aumac_powerdown(sc);
840 
841 	/* Mark the interface as down and cancel the watchdog timer. */
842 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
843 	ifp->if_timer = 0;
844 }
845 
846 /*
847  * aumac_powerdown:
848  *
849  *	Power down the MAC.
850  */
851 static void
852 aumac_powerdown(struct aumac_softc *sc)
853 {
854 
855 	/* Disable the MAC clocks, and place the device in reset. */
856 	// bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0, MACEN_JP);
857 
858 	// delay(10000);
859 }
860 
861 /*
862  * aumac_powerup:
863  *
864  *	Bring the device out of reset.
865  */
866 static void
867 aumac_powerup(struct aumac_softc *sc)
868 {
869 
870 	/* Enable clocks to the MAC. */
871 	bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0, MACEN_JP|MACEN_CE);
872 
873 	/* Enable MAC, coherent transactions, pass only valid frames. */
874 	bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0,
875 	    MACEN_E2|MACEN_E1|MACEN_E0|MACEN_CE);
876 
877 	delay(20000);
878 }
879 
880 /*
881  * aumac_set_filter:
882  *
883  *	Set up the receive filter.
884  */
885 static void
886 aumac_set_filter(struct aumac_softc *sc)
887 {
888 	struct ethercom *ec = &sc->sc_ethercom;
889 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
890 	struct ether_multi *enm;
891 	struct ether_multistep step;
892 	const uint8_t *enaddr = LLADDR(ifp->if_sadl);
893 	uint32_t mchash[2], crc;
894 
895 	sc->sc_control &= ~(CONTROL_PM | CONTROL_PR);
896 
897 	/* Stop the receiver. */
898 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
899 	    sc->sc_control & ~CONTROL_RE);
900 
901 	if (ifp->if_flags & IFF_PROMISC) {
902 		sc->sc_control |= CONTROL_PR;
903 		goto allmulti;
904 	}
905 
906 	/* Set the station address. */
907 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_ADDRHIGH,
908 	    enaddr[4] | (enaddr[5] << 8));
909 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_ADDRLOW,
910 	    enaddr[0] | (enaddr[1] << 8) | (enaddr[2] << 16) |
911 	    (enaddr[3] << 24));
912 
913 	sc->sc_control |= CONTROL_HP;
914 
915 	mchash[0] = mchash[1] = 0;
916 
917 	/*
918 	 * Set up the multicast address filter by passing all multicast
919 	 * addresses through a CRC generator, and then using the high
920 	 * order 6 bits as an index into the 64-bit multicast hash table.
921 	 * The high order bits select the word, while the rest of the bits
922 	 * select the bit within the word.
923 	 */
924 	ETHER_FIRST_MULTI(step, ec, enm);
925 	while (enm != NULL) {
926 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
927 			/*
928 			 * We must listen to a range of multicast addresses.
929 			 * For now, just accept all multicasts, rather than
930 			 * trying to set only those filter bits needed to match
931 			 * the range.  (At this time, the only use of address
932 			 * ranges is for IP multicast routing, for which the
933 			 * range is large enough to require all bits set.)
934 			 */
935 			goto allmulti;
936 		}
937 
938 		crc = ether_crc32_be(enm->enm_addrlo, ETHER_ADDR_LEN);
939 
940 		/* Just want the 6 most significant bits. */
941 		crc >>= 26;
942 
943 		/* Set the corresponding bit in the filter. */
944 		mchash[crc >> 5] |= 1U << (crc & 0x1f);
945 
946 		ETHER_NEXT_MULTI(step, enm);
947 	}
948 
949 	ifp->if_flags &= ~IFF_ALLMULTI;
950 
951 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_HASHHIGH,
952 	    mchash[1]);
953 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_HASHLOW,
954 	    mchash[0]);
955 
956 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
957 	    sc->sc_control);
958 	return;
959 
960  allmulti:
961 	sc->sc_control |= CONTROL_PM;
962 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
963 	    sc->sc_control);
964 }
965 
966 /*
967  * aumac_mediastatus:	[ifmedia interface function]
968  *
969  *	Get the current interface media status.
970  */
971 static void
972 aumac_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
973 {
974 	struct aumac_softc *sc = ifp->if_softc;
975 
976 	mii_pollstat(&sc->sc_mii);
977 	ifmr->ifm_status = sc->sc_mii.mii_media_status;
978 	ifmr->ifm_active = sc->sc_mii.mii_media_active;
979 }
980 
981 /*
982  * aumac_mediachange:	[ifmedia interface function]
983  *
984  *	Set hardware to newly selected media.
985  */
986 static int
987 aumac_mediachange(struct ifnet *ifp)
988 {
989 	struct aumac_softc *sc = ifp->if_softc;
990 
991 	if (ifp->if_flags & IFF_UP)
992 		mii_mediachg(&sc->sc_mii);
993 	return (0);
994 }
995 
996 /*
997  * aumac_mii_wait:
998  *
999  *	Wait for the MII interface to not be busy.
1000  */
1001 static int
1002 aumac_mii_wait(struct aumac_softc *sc, const char *msg)
1003 {
1004 	int i;
1005 
1006 	for (i = 0; i < 10000; i++) {
1007 		if ((bus_space_read_4(sc->sc_st, sc->sc_mac_sh,
1008 		     MAC_MIICTRL) & MIICTRL_MB) == 0)
1009 			return (0);
1010 		delay(10);
1011 	}
1012 
1013 	printf("%s: MII failed to %s\n", sc->sc_dev.dv_xname, msg);
1014 	return (1);
1015 }
1016 
1017 /*
1018  * aumac_mii_readreg:	[mii interface function]
1019  *
1020  *	Read a PHY register on the MII.
1021  */
1022 static int
1023 aumac_mii_readreg(struct device *self, int phy, int reg)
1024 {
1025 	struct aumac_softc *sc = (void *) self;
1026 
1027 	if (aumac_mii_wait(sc, "become ready"))
1028 		return (0);
1029 
1030 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_MIICTRL,
1031 	    MIICTRL_PHYADDR(phy) | MIICTRL_MIIREG(reg));
1032 
1033 	if (aumac_mii_wait(sc, "complete"))
1034 		return (0);
1035 
1036 	return (bus_space_read_4(sc->sc_st, sc->sc_mac_sh, MAC_MIIDATA) &
1037 	    MIIDATA_MASK);
1038 }
1039 
1040 /*
1041  * aumac_mii_writereg:	[mii interface function]
1042  *
1043  *	Write a PHY register on the MII.
1044  */
1045 static void
1046 aumac_mii_writereg(struct device *self, int phy, int reg, int val)
1047 {
1048 	struct aumac_softc *sc = (void *) self;
1049 
1050 	if (aumac_mii_wait(sc, "become ready"))
1051 		return;
1052 
1053 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_MIIDATA, val);
1054 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_MIICTRL,
1055 	    MIICTRL_PHYADDR(phy) | MIICTRL_MIIREG(reg) | MIICTRL_MW);
1056 
1057 	(void) aumac_mii_wait(sc, "complete");
1058 }
1059 
1060 /*
1061  * aumac_mii_statchg:	[mii interface function]
1062  *
1063  *	Callback from MII layer when media changes.
1064  */
1065 static void
1066 aumac_mii_statchg(struct device *self)
1067 {
1068 	struct aumac_softc *sc = (void *) self;
1069 
1070 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0)
1071 		sc->sc_control |= CONTROL_F;
1072 	else
1073 		sc->sc_control &= ~CONTROL_F;
1074 
1075 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
1076 	    sc->sc_control);
1077 }
1078