xref: /netbsd-src/sys/arch/mips/alchemy/dev/if_aumac.c (revision 6a493d6bc668897c91594964a732d38505b70cbb)
1 /* $NetBSD: if_aumac.c,v 1.37 2012/07/22 14:32:51 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 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 1.37 2012/07/22 14:32:51 matt Exp $");
50 
51 
52 
53 #include <sys/param.h>
54 #include <sys/bus.h>
55 #include <sys/callout.h>
56 #include <sys/device.h>
57 #include <sys/endian.h>
58 #include <sys/errno.h>
59 #include <sys/intr.h>
60 #include <sys/ioctl.h>
61 #include <sys/kernel.h>
62 #include <sys/mbuf.h>
63 #include <sys/malloc.h>
64 #include <sys/socket.h>
65 
66 #include <uvm/uvm.h>		/* for PAGE_SIZE */
67 
68 #include <net/if.h>
69 #include <net/if_dl.h>
70 #include <net/if_media.h>
71 #include <net/if_ether.h>
72 
73 #include <net/bpf.h>
74 #include <sys/rnd.h>
75 
76 #include <dev/mii/mii.h>
77 #include <dev/mii/miivar.h>
78 
79 #include <mips/alchemy/include/aureg.h>
80 #include <mips/alchemy/include/auvar.h>
81 #include <mips/alchemy/include/aubusvar.h>
82 #include <mips/alchemy/dev/if_aumacreg.h>
83 
84 /*
85  * The Au1X00 MAC has 4 transmit and receive descriptors.  Each buffer
86  * must consist of a single DMA segment, and must be aligned to a 2K
87  * boundary.  Therefore, this driver does not perform DMA directly
88  * to/from mbufs.  Instead, we copy the data to/from buffers allocated
89  * at device attach time.
90  *
91  * We also skip the bus_dma dance.  The MAC is built in to the CPU, so
92  * there's little point in not making assumptions based on the CPU type.
93  * We also program the Au1X00 cache to be DMA coherent, so the buffers
94  * are accessed via KSEG0 addresses.
95  */
96 #define	AUMAC_NTXDESC		4
97 #define	AUMAC_NTXDESC_MASK	(AUMAC_NTXDESC - 1)
98 
99 #define	AUMAC_NRXDESC		4
100 #define	AUMAC_NRXDESC_MASK	(AUMAC_NRXDESC - 1)
101 
102 #define	AUMAC_NEXTTX(x)		(((x) + 1) & AUMAC_NTXDESC_MASK)
103 #define	AUMAC_NEXTRX(x)		(((x) + 1) & AUMAC_NRXDESC_MASK)
104 
105 #define	AUMAC_TXBUF_OFFSET	0
106 #define	AUMAC_RXBUF_OFFSET	(MAC_BUFLEN * AUMAC_NTXDESC)
107 #define	AUMAC_BUFSIZE		(MAC_BUFLEN * (AUMAC_NTXDESC + AUMAC_NRXDESC))
108 
109 struct aumac_buf {
110 	vaddr_t buf_vaddr;		/* virtual address of buffer */
111 	bus_addr_t buf_paddr;		/* DMA address of buffer */
112 };
113 
114 /*
115  * Software state per device.
116  */
117 struct aumac_softc {
118 	device_t sc_dev;		/* generic device information */
119 	bus_space_tag_t sc_st;		/* bus space tag */
120 	bus_space_handle_t sc_mac_sh;	/* MAC space handle */
121 	bus_space_handle_t sc_macen_sh;	/* MAC enable space handle */
122 	bus_space_handle_t sc_dma_sh;	/* DMA space handle */
123 	struct ethercom sc_ethercom;	/* Ethernet common data */
124 	void *sc_sdhook;		/* shutdown hook */
125 
126 	int sc_irq;
127 	void *sc_ih;			/* interrupt cookie */
128 
129 	struct mii_data sc_mii;		/* MII/media information */
130 
131 	struct callout sc_tick_ch;	/* tick callout */
132 
133 	/* Transmit and receive buffers */
134 	struct aumac_buf sc_txbufs[AUMAC_NTXDESC];
135 	struct aumac_buf sc_rxbufs[AUMAC_NRXDESC];
136 	void *sc_bufaddr;
137 
138 	int sc_txfree;			/* number of free Tx descriptors */
139 	int sc_txnext;			/* next Tx descriptor to use */
140 	int sc_txdirty;			/* first dirty Tx descriptor */
141 
142 	int sc_rxptr;			/* next ready Rx descriptor */
143 
144 	krndsource_t rnd_source;
145 
146 #ifdef AUMAC_EVENT_COUNTERS
147 	struct evcnt sc_ev_txstall;	/* Tx stalled */
148 	struct evcnt sc_ev_rxstall;	/* Rx stalled */
149 	struct evcnt sc_ev_txintr;	/* Tx interrupts */
150 	struct evcnt sc_ev_rxintr;	/* Rx interrupts */
151 #endif
152 
153 	uint32_t sc_control;		/* MAC_CONTROL contents */
154 	uint32_t sc_flowctrl;		/* MAC_FLOWCTRL contents */
155 };
156 
157 #ifdef AUMAC_EVENT_COUNTERS
158 #define	AUMAC_EVCNT_INCR(ev)	(ev)->ev_count++
159 #else
160 #define	AUMAC_EVCNT_INCR(ev)	/* nothing */
161 #endif
162 
163 #define	AUMAC_INIT_RXDESC(sc, x)					\
164 do {									\
165 	bus_space_write_4((sc)->sc_st, (sc)->sc_dma_sh,			\
166 	    MACDMA_RX_STAT((x)), 0);					\
167 	bus_space_write_4((sc)->sc_st, (sc)->sc_dma_sh,			\
168 	    MACDMA_RX_ADDR((x)),					\
169 	    (sc)->sc_rxbufs[(x)].buf_paddr | RX_ADDR_EN);		\
170 } while (/*CONSTCOND*/0)
171 
172 static void	aumac_start(struct ifnet *);
173 static void	aumac_watchdog(struct ifnet *);
174 static int	aumac_ioctl(struct ifnet *, u_long, void *);
175 static int	aumac_init(struct ifnet *);
176 static void	aumac_stop(struct ifnet *, int);
177 
178 static void	aumac_shutdown(void *);
179 
180 static void	aumac_tick(void *);
181 
182 static void	aumac_set_filter(struct aumac_softc *);
183 
184 static void	aumac_powerup(struct aumac_softc *);
185 static void	aumac_powerdown(struct aumac_softc *);
186 
187 static int	aumac_intr(void *);
188 static int	aumac_txintr(struct aumac_softc *);
189 static int	aumac_rxintr(struct aumac_softc *);
190 
191 static int	aumac_mii_readreg(device_t, int, int);
192 static void	aumac_mii_writereg(device_t, int, int, int);
193 static void	aumac_mii_statchg(struct ifnet *);
194 static int	aumac_mii_wait(struct aumac_softc *, const char *);
195 
196 static int	aumac_match(device_t, struct cfdata *, void *);
197 static void	aumac_attach(device_t, device_t, void *);
198 
199 int	aumac_copy_small = 0;
200 
201 CFATTACH_DECL_NEW(aumac, sizeof(struct aumac_softc),
202     aumac_match, aumac_attach, NULL, NULL);
203 
204 static int
205 aumac_match(device_t parent, struct cfdata *cf, void *aux)
206 {
207 	struct aubus_attach_args *aa = aux;
208 
209 	if (strcmp(aa->aa_name, cf->cf_name) == 0)
210 		return (1);
211 
212 	return (0);
213 }
214 
215 static void
216 aumac_attach(device_t parent, device_t self, void *aux)
217 {
218 	const uint8_t *enaddr;
219 	prop_data_t ea;
220 	struct aumac_softc *sc = device_private(self);
221 	struct aubus_attach_args *aa = aux;
222 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
223 	struct pglist pglist;
224 	paddr_t bufaddr;
225 	vaddr_t vbufaddr;
226 	int i;
227 
228 	callout_init(&sc->sc_tick_ch, 0);
229 
230 	aprint_normal(": Au1X00 10/100 Ethernet\n");
231 	aprint_naive("\n");
232 
233 	sc->sc_dev = self;
234 	sc->sc_st = aa->aa_st;
235 
236 	/* Get the MAC address. */
237 	ea = prop_dictionary_get(device_properties(self), "mac-address");
238 	if (ea == NULL) {
239 		aprint_error_dev(self, "unable to get mac-addr property\n");
240 		return;
241 	}
242 	KASSERT(prop_object_type(ea) == PROP_TYPE_DATA);
243 	KASSERT(prop_data_size(ea) == ETHER_ADDR_LEN);
244 	enaddr = prop_data_data_nocopy(ea);
245 
246 	aprint_normal_dev(self, "Ethernet address %s\n", 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 		aprint_error_dev(self, "unable to map MAC registers\n");
252 		return;
253 	}
254 	if (bus_space_map(sc->sc_st, aa->aa_addrs[AA_MAC_ENABLE],
255 	    MACENx_SIZE, 0, &sc->sc_macen_sh) != 0) {
256 		aprint_error_dev(self, "unable to map MACEN registers\n");
257 		return;
258 	}
259 	if (bus_space_map(sc->sc_st, aa->aa_addrs[AA_MAC_DMA_BASE],
260 	    MACx_DMA_SIZE, 0, &sc->sc_dma_sh) != 0) {
261 		aprint_error_dev(self, "unable to map MACDMA registers\n");
262 		return;
263 	}
264 
265 	/* Make sure the MAC is powered off. */
266 	aumac_powerdown(sc);
267 
268 	/* Hook up the interrupt handler. */
269 	sc->sc_ih = au_intr_establish(aa->aa_irq[0], 1, IPL_NET, IST_LEVEL,
270 	    aumac_intr, sc);
271 	if (sc->sc_ih == NULL) {
272 		aprint_error_dev(self,
273 		    "unable to register interrupt handler\n");
274 		return;
275 	}
276 	sc->sc_irq = aa->aa_irq[0];
277 	au_intr_disable(sc->sc_irq);
278 
279 	/*
280 	 * Allocate space for the transmit and receive buffers.
281 	 */
282 	if (uvm_pglistalloc(AUMAC_BUFSIZE, 0, ctob(physmem), PAGE_SIZE, 0,
283 	    &pglist, 1, 0))
284 		return;
285 
286 	bufaddr = VM_PAGE_TO_PHYS(TAILQ_FIRST(&pglist));
287 	vbufaddr = MIPS_PHYS_TO_KSEG0(bufaddr);
288 
289 	for (i = 0; i < AUMAC_NTXDESC; i++) {
290 		int offset = AUMAC_TXBUF_OFFSET + (i * MAC_BUFLEN);
291 
292 		sc->sc_txbufs[i].buf_vaddr = vbufaddr + offset;
293 		sc->sc_txbufs[i].buf_paddr = bufaddr + offset;
294 	}
295 
296 	for (i = 0; i < AUMAC_NRXDESC; i++) {
297 		int offset = AUMAC_RXBUF_OFFSET + (i * MAC_BUFLEN);
298 
299 		sc->sc_rxbufs[i].buf_vaddr = vbufaddr + offset;
300 		sc->sc_rxbufs[i].buf_paddr = bufaddr + offset;
301 	}
302 
303 	/*
304 	 * Power up the MAC before accessing any MAC registers (including
305 	 * MII configuration.
306 	 */
307 	aumac_powerup(sc);
308 
309 	/*
310 	 * Initialize the media structures and probe the MII.
311 	 */
312 	sc->sc_mii.mii_ifp = ifp;
313 	sc->sc_mii.mii_readreg = aumac_mii_readreg;
314 	sc->sc_mii.mii_writereg = aumac_mii_writereg;
315 	sc->sc_mii.mii_statchg = aumac_mii_statchg;
316 	sc->sc_ethercom.ec_mii = &sc->sc_mii;
317 	ifmedia_init(&sc->sc_mii.mii_media, 0, ether_mediachange,
318 	    ether_mediastatus);
319 
320 	mii_attach(self, &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, device_xname(self));
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 	rnd_attach_source(&sc->rnd_source, device_xname(self),
344 	    RND_TYPE_NET, 0);
345 
346 #ifdef AUMAC_EVENT_COUNTERS
347 	evcnt_attach_dynamic(&sc->sc_ev_txstall, EVCNT_TYPE_MISC,
348 	    NULL, device_xname(self), "txstall");
349 	evcnt_attach_dynamic(&sc->sc_ev_rxstall, EVCNT_TYPE_MISC,
350 	    NULL, device_xname(self), "rxstall");
351 	evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_MISC,
352 	    NULL, device_xname(self), "txintr");
353 	evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_MISC,
354 	    NULL, device_xname(self), "rxintr");
355 #endif
356 
357 	/* Make sure the interface is shutdown during reboot. */
358 	sc->sc_sdhook = shutdownhook_establish(aumac_shutdown, sc);
359 	if (sc->sc_sdhook == NULL)
360 		aprint_error_dev(self,
361 		    "WARNING: unable to establish shutdown hook\n");
362 	return;
363 }
364 
365 /*
366  * aumac_shutdown:
367  *
368  *	Make sure the interface is stopped at reboot time.
369  */
370 static void
371 aumac_shutdown(void *arg)
372 {
373 	struct aumac_softc *sc = arg;
374 
375 	aumac_stop(&sc->sc_ethercom.ec_if, 1);
376 
377 	/*
378 	 * XXX aumac_stop leaves device powered up at the moment
379 	 * XXX but this still isn't enough to keep yamon happy... :-(
380 	 */
381 	bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0, 0);
382 }
383 
384 /*
385  * aumac_start:		[ifnet interface function]
386  *
387  *	Start packet transmission on the interface.
388  */
389 static void
390 aumac_start(struct ifnet *ifp)
391 {
392 	struct aumac_softc *sc = ifp->if_softc;
393 	struct mbuf *m;
394 	int nexttx;
395 
396 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
397 		return;
398 
399 	/*
400 	 * Loop through the send queue, setting up transmit descriptors
401 	 * unitl we drain the queue, or use up all available transmit
402 	 * descriptors.
403 	 */
404 	for (;;) {
405 		/* Grab a packet off the queue. */
406 		IFQ_POLL(&ifp->if_snd, m);
407 		if (m == NULL)
408 			return;
409 
410 		/* Get a spare descriptor. */
411 		if (sc->sc_txfree == 0) {
412 			/* No more slots left; notify upper layer. */
413 			ifp->if_flags |= IFF_OACTIVE;
414 			AUMAC_EVCNT_INCR(&sc->sc_ev_txstall);
415 			return;
416 		}
417 		nexttx = sc->sc_txnext;
418 
419 		IFQ_DEQUEUE(&ifp->if_snd, m);
420 
421 		/*
422 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
423 		 */
424 
425 		m_copydata(m, 0, m->m_pkthdr.len,
426 		    (void *)sc->sc_txbufs[nexttx].buf_vaddr);
427 
428 		/* Zero out the remainder of any short packets. */
429 		if (m->m_pkthdr.len < (ETHER_MIN_LEN - ETHER_CRC_LEN))
430 			memset((char *)sc->sc_txbufs[nexttx].buf_vaddr +
431 			    m->m_pkthdr.len, 0,
432 			    ETHER_MIN_LEN - ETHER_CRC_LEN - m->m_pkthdr.len);
433 
434 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
435 		    MACDMA_TX_STAT(nexttx), 0);
436 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
437 		    MACDMA_TX_LEN(nexttx),
438 		    m->m_pkthdr.len < (ETHER_MIN_LEN - ETHER_CRC_LEN) ?
439 		    ETHER_MIN_LEN - ETHER_CRC_LEN : m->m_pkthdr.len);
440 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
441 		    MACDMA_TX_ADDR(nexttx),
442 		    sc->sc_txbufs[nexttx].buf_paddr | TX_ADDR_EN);
443 		/* XXX - needed??  we should be coherent */
444 		bus_space_barrier(sc->sc_st, sc->sc_dma_sh, 0 /* XXX */,
445 		    0 /* XXX */, BUS_SPACE_BARRIER_WRITE);
446 
447 		/* Advance the Tx pointer. */
448 		sc->sc_txfree--;
449 		sc->sc_txnext = AUMAC_NEXTTX(nexttx);
450 
451 		/* Pass the packet to any BPF listeners. */
452 		bpf_mtap(ifp, m);
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", device_xname(sc->sc_dev));
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, void *data)
486 {
487 	struct aumac_softc *sc = ifp->if_softc;
488 	int s, error;
489 
490 	s = splnet();
491 
492 	error = ether_ioctl(ifp, cmd, data);
493 	if (error == ENETRESET) {
494 		/*
495 		 * Multicast list has changed; set the hardware filter
496 		 * accordingly.
497 		 */
498 		if (ifp->if_flags & IFF_RUNNING)
499 			aumac_set_filter(sc);
500 		error = 0;
501 	}
502 
503 	/* Try to get more packets going. */
504 	aumac_start(ifp);
505 
506 	splx(s);
507 	return (error);
508 }
509 
510 /*
511  * aumac_intr:
512  *
513  *	Interrupt service routine.
514  */
515 static int
516 aumac_intr(void *arg)
517 {
518 	struct aumac_softc *sc = arg;
519 	int status;
520 
521 	/*
522 	 * There aren't really any interrupt status bits on the
523 	 * Au1X00 MAC, and each MAC has a dedicated interrupt
524 	 * in the CPU's built-in interrupt controller.  Just
525 	 * check for new incoming packets, and then Tx completions
526 	 * (for status updating).
527 	 */
528 	if ((sc->sc_ethercom.ec_if.if_flags & IFF_RUNNING) == 0)
529 		return (0);
530 
531 	status = aumac_rxintr(sc);
532 	status += aumac_txintr(sc);
533 
534 	rnd_add_uint32(&sc->rnd_source, status);
535 
536 	return status;
537 }
538 
539 /*
540  * aumac_txintr:
541  *
542  *	Helper; handle transmit interrupts.
543  */
544 static int
545 aumac_txintr(struct aumac_softc *sc)
546 {
547 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
548 	uint32_t stat;
549 	int i;
550 	int pkts = 0;
551 
552 	for (i = sc->sc_txdirty; sc->sc_txfree != AUMAC_NTXDESC;
553 	     i = AUMAC_NEXTTX(i)) {
554 		if ((bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
555 		     MACDMA_TX_ADDR(i)) & TX_ADDR_DN) == 0)
556 			break;
557 		pkts++;
558 
559 		/* ACK interrupt. */
560 		bus_space_write_4(sc->sc_st, sc->sc_dma_sh,
561 		    MACDMA_TX_ADDR(i), 0);
562 
563 		stat = bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
564 		    MACDMA_TX_STAT(i));
565 
566 		if (stat & TX_STAT_FA) {
567 			/* XXX STATS */
568 			ifp->if_oerrors++;
569 		} else
570 			ifp->if_opackets++;
571 
572 		if (stat & TX_STAT_EC)
573 			ifp->if_collisions += 16;
574 		else
575 			ifp->if_collisions += TX_STAT_CC(stat);
576 
577 		sc->sc_txfree++;
578 		ifp->if_flags &= ~IFF_OACTIVE;
579 
580 		/* Try to queue more packets. */
581 		aumac_start(ifp);
582 	}
583 
584 	if (pkts)
585 		AUMAC_EVCNT_INCR(&sc->sc_ev_txintr);
586 
587 	/* Update the dirty descriptor pointer. */
588 	sc->sc_txdirty = i;
589 
590 	/*
591 	 * If there are no more pending transmissions, cancel the watchdog
592 	 * timer.
593 	 */
594 	if (sc->sc_txfree == AUMAC_NTXDESC)
595 		ifp->if_timer = 0;
596 
597 	return pkts;
598 }
599 
600 /*
601  * aumac_rxintr:
602  *
603  *	Helper; handle receive interrupts.
604  */
605 static int
606 aumac_rxintr(struct aumac_softc *sc)
607 {
608 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
609 	struct mbuf *m;
610 	uint32_t stat;
611 	int i, len;
612 	int pkts = 0;
613 
614 	for (i = sc->sc_rxptr;; i = AUMAC_NEXTRX(i)) {
615 		if ((bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
616 		     MACDMA_RX_ADDR(i)) & RX_ADDR_DN) == 0)
617 			break;
618 		pkts++;
619 
620 		stat = bus_space_read_4(sc->sc_st, sc->sc_dma_sh,
621 		    MACDMA_RX_STAT(i));
622 
623 #define PRINTERR(str)							\
624 	do {								\
625 		error++;						\
626 		printf("%s: %s\n", device_xname(sc->sc_dev), str);	\
627 	} while (0)
628 
629 		if (stat & RX_STAT_ERRS) {
630 			int error = 0;
631 
632 #if 0	/*
633 	 * Missed frames are a semi-frequent occurence with this hardware,
634 	 * and reporting of them just makes everything run slower and fills
635 	 * the system log.  Be silent.
636 	 *
637 	 * Additionally, this missed bit indicates an error with the previous
638 	 * packet, and not with this one!  So PRINTERR is definitely wrong
639 	 * here.
640 	 *
641 	 * These should probably all be converted to evcnt counters anyway.
642 	 */
643 			if (stat & RX_STAT_MI)
644 				PRINTERR("missed frame");
645 #endif
646 			if (stat & RX_STAT_UC)
647 				PRINTERR("unknown control frame");
648 			if (stat & RX_STAT_LE)
649 				PRINTERR("short frame");
650 			if (stat & RX_STAT_CR)
651 				PRINTERR("CRC error");
652 			if (stat & RX_STAT_ME)
653 				PRINTERR("medium error");
654 			if (stat & RX_STAT_CS)
655 				PRINTERR("late collision");
656 			if (stat & RX_STAT_FL)
657 				PRINTERR("frame too big");
658 			if (stat & RX_STAT_RF)
659 				PRINTERR("runt frame (collision)");
660 			if (stat & RX_STAT_WT)
661 				PRINTERR("watch dog");
662 			if (stat & RX_STAT_DB) {
663 				if (stat & (RX_STAT_CS | RX_STAT_RF |
664 				    RX_STAT_CR)) {
665 					if (!error)
666 						goto pktok;
667 				} else
668 					PRINTERR("dribbling bit");
669 			}
670 #undef PRINTERR
671 			ifp->if_ierrors++;
672 
673  dropit:
674 			/* reuse the current descriptor */
675 			AUMAC_INIT_RXDESC(sc, i);
676 			continue;
677 		}
678  pktok:
679 		len = RX_STAT_L(stat);
680 
681 		/*
682 		 * The Au1X00 MAC includes the CRC with every packet;
683 		 * trim it off here.
684 		 */
685 		len -= ETHER_CRC_LEN;
686 
687 		/*
688 		 * Truncate the packet if it's too big to fit in
689 		 * a single mbuf cluster.
690 		 */
691 		if (len > MCLBYTES - 2)
692 			len = MCLBYTES - 2;
693 
694 		MGETHDR(m, M_DONTWAIT, MT_DATA);
695 		if (m == NULL) {
696 			printf("%s: unable to allocate Rx mbuf\n",
697 			    device_xname(sc->sc_dev));
698 			goto dropit;
699 		}
700 		if (len > MHLEN - 2) {
701 			MCLGET(m, M_DONTWAIT);
702 			if ((m->m_flags & M_EXT) == 0) {
703 				printf("%s: unable to allocate Rx cluster\n",
704 				    device_xname(sc->sc_dev));
705 				m_freem(m);
706 				goto dropit;
707 			}
708 		}
709 
710 		m->m_data += 2;		/* align payload */
711 		memcpy(mtod(m, void *),
712 		    (void *)sc->sc_rxbufs[i].buf_vaddr, len);
713 		AUMAC_INIT_RXDESC(sc, i);
714 
715 		m->m_pkthdr.rcvif = ifp;
716 		m->m_pkthdr.len = m->m_len = len;
717 
718 		/* Pass this up to any BPF listeners. */
719 		bpf_mtap(ifp, m);
720 
721 		/* Pass it on. */
722 		(*ifp->if_input)(ifp, m);
723 		ifp->if_ipackets++;
724 	}
725 	if (pkts)
726 		AUMAC_EVCNT_INCR(&sc->sc_ev_rxintr);
727 	if (pkts == AUMAC_NRXDESC)
728 		AUMAC_EVCNT_INCR(&sc->sc_ev_rxstall);
729 
730 	/* Update the receive pointer. */
731 	sc->sc_rxptr = i;
732 
733 	return pkts;
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 	if ((error = ether_mediachange(ifp)) != 0)
800 		goto out;
801 
802 	/*
803 	 * Set the receive filter.  This will actually start the transmit
804 	 * and receive processes.
805 	 */
806 	aumac_set_filter(sc);
807 
808 	/* Start the one second clock. */
809 	callout_reset(&sc->sc_tick_ch, hz, aumac_tick, sc);
810 
811 	/* ...all done! */
812 	ifp->if_flags |= IFF_RUNNING;
813 	ifp->if_flags &= ~IFF_OACTIVE;
814 
815 	au_intr_enable(sc->sc_irq);
816 out:
817 	if (error)
818 		printf("%s: interface not running\n", device_xname(sc->sc_dev));
819 	return (error);
820 }
821 
822 /*
823  * aumac_stop:		[ifnet interface function]
824  *
825  *	Stop transmission on the interface.
826  */
827 static void
828 aumac_stop(struct ifnet *ifp, int disable)
829 {
830 	struct aumac_softc *sc = ifp->if_softc;
831 
832 	/* Stop the one-second clock. */
833 	callout_stop(&sc->sc_tick_ch);
834 
835 	/* Down the MII. */
836 	mii_down(&sc->sc_mii);
837 
838 	/* Stop the transmit and receive processes. */
839 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL, 0);
840 
841 	/* Power down/reset the MAC. */
842 	aumac_powerdown(sc);
843 
844 	au_intr_disable(sc->sc_irq);
845 
846 	/* Mark the interface as down and cancel the watchdog timer. */
847 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
848 	ifp->if_timer = 0;
849 }
850 
851 /*
852  * aumac_powerdown:
853  *
854  *	Power down the MAC.
855  */
856 static void
857 aumac_powerdown(struct aumac_softc *sc)
858 {
859 
860 	/* Disable the MAC clocks, and place the device in reset. */
861 	// bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0, MACEN_JP);
862 
863 	// delay(10000);
864 }
865 
866 /*
867  * aumac_powerup:
868  *
869  *	Bring the device out of reset.
870  */
871 static void
872 aumac_powerup(struct aumac_softc *sc)
873 {
874 
875 	/* Enable clocks to the MAC. */
876 	bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0, MACEN_JP|MACEN_CE);
877 
878 	/* Enable MAC, coherent transactions, pass only valid frames. */
879 	bus_space_write_4(sc->sc_st, sc->sc_macen_sh, 0,
880 	    MACEN_E2|MACEN_E1|MACEN_E0|MACEN_CE);
881 
882 	delay(20000);
883 }
884 
885 /*
886  * aumac_set_filter:
887  *
888  *	Set up the receive filter.
889  */
890 static void
891 aumac_set_filter(struct aumac_softc *sc)
892 {
893 	struct ethercom *ec = &sc->sc_ethercom;
894 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
895 	struct ether_multi *enm;
896 	struct ether_multistep step;
897 	const uint8_t *enaddr = CLLADDR(ifp->if_sadl);
898 	uint32_t mchash[2], crc;
899 
900 	sc->sc_control &= ~(CONTROL_PM | CONTROL_PR);
901 
902 	/* Stop the receiver. */
903 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
904 	    sc->sc_control & ~CONTROL_RE);
905 
906 	if (ifp->if_flags & IFF_PROMISC) {
907 		sc->sc_control |= CONTROL_PR;
908 		goto allmulti;
909 	}
910 
911 	/* Set the station address. */
912 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_ADDRHIGH,
913 	    enaddr[4] | (enaddr[5] << 8));
914 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_ADDRLOW,
915 	    enaddr[0] | (enaddr[1] << 8) | (enaddr[2] << 16) |
916 	    (enaddr[3] << 24));
917 
918 	sc->sc_control |= CONTROL_HP;
919 
920 	mchash[0] = mchash[1] = 0;
921 
922 	/*
923 	 * Set up the multicast address filter by passing all multicast
924 	 * addresses through a CRC generator, and then using the high
925 	 * order 6 bits as an index into the 64-bit multicast hash table.
926 	 * The high order bits select the word, while the rest of the bits
927 	 * select the bit within the word.
928 	 */
929 	ETHER_FIRST_MULTI(step, ec, enm);
930 	while (enm != NULL) {
931 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
932 			/*
933 			 * We must listen to a range of multicast addresses.
934 			 * For now, just accept all multicasts, rather than
935 			 * trying to set only those filter bits needed to match
936 			 * the range.  (At this time, the only use of address
937 			 * ranges is for IP multicast routing, for which the
938 			 * range is large enough to require all bits set.)
939 			 */
940 			goto allmulti;
941 		}
942 
943 		crc = ether_crc32_be(enm->enm_addrlo, ETHER_ADDR_LEN);
944 
945 		/* Just want the 6 most significant bits. */
946 		crc >>= 26;
947 
948 		/* Set the corresponding bit in the filter. */
949 		mchash[crc >> 5] |= 1U << (crc & 0x1f);
950 
951 		ETHER_NEXT_MULTI(step, enm);
952 	}
953 
954 	ifp->if_flags &= ~IFF_ALLMULTI;
955 
956 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_HASHHIGH,
957 	    mchash[1]);
958 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_HASHLOW,
959 	    mchash[0]);
960 
961 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
962 	    sc->sc_control);
963 	return;
964 
965  allmulti:
966 	sc->sc_control |= CONTROL_PM;
967 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
968 	    sc->sc_control);
969 }
970 
971 /*
972  * aumac_mii_wait:
973  *
974  *	Wait for the MII interface to not be busy.
975  */
976 static int
977 aumac_mii_wait(struct aumac_softc *sc, const char *msg)
978 {
979 	int i;
980 
981 	for (i = 0; i < 10000; i++) {
982 		if ((bus_space_read_4(sc->sc_st, sc->sc_mac_sh,
983 		     MAC_MIICTRL) & MIICTRL_MB) == 0)
984 			return (0);
985 		delay(10);
986 	}
987 
988 	printf("%s: MII failed to %s\n", device_xname(sc->sc_dev), msg);
989 	return (1);
990 }
991 
992 /*
993  * aumac_mii_readreg:	[mii interface function]
994  *
995  *	Read a PHY register on the MII.
996  */
997 static int
998 aumac_mii_readreg(device_t self, int phy, int reg)
999 {
1000 	struct aumac_softc *sc = device_private(self);
1001 
1002 	if (aumac_mii_wait(sc, "become ready"))
1003 		return (0);
1004 
1005 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_MIICTRL,
1006 	    MIICTRL_PHYADDR(phy) | MIICTRL_MIIREG(reg));
1007 
1008 	if (aumac_mii_wait(sc, "complete"))
1009 		return (0);
1010 
1011 	return (bus_space_read_4(sc->sc_st, sc->sc_mac_sh, MAC_MIIDATA) &
1012 	    MIIDATA_MASK);
1013 }
1014 
1015 /*
1016  * aumac_mii_writereg:	[mii interface function]
1017  *
1018  *	Write a PHY register on the MII.
1019  */
1020 static void
1021 aumac_mii_writereg(device_t self, int phy, int reg, int val)
1022 {
1023 	struct aumac_softc *sc = device_private(self);
1024 
1025 	if (aumac_mii_wait(sc, "become ready"))
1026 		return;
1027 
1028 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_MIIDATA, val);
1029 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_MIICTRL,
1030 	    MIICTRL_PHYADDR(phy) | MIICTRL_MIIREG(reg) | MIICTRL_MW);
1031 
1032 	(void) aumac_mii_wait(sc, "complete");
1033 }
1034 
1035 /*
1036  * aumac_mii_statchg:	[mii interface function]
1037  *
1038  *	Callback from MII layer when media changes.
1039  */
1040 static void
1041 aumac_mii_statchg(struct ifnet *ifp)
1042 {
1043 	struct aumac_softc *sc = ifp->if_softc;
1044 
1045 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0)
1046 		sc->sc_control |= CONTROL_F;
1047 	else
1048 		sc->sc_control &= ~CONTROL_F;
1049 
1050 	bus_space_write_4(sc->sc_st, sc->sc_mac_sh, MAC_CONTROL,
1051 	    sc->sc_control);
1052 }
1053