xref: /freebsd/sys/dev/sis/if_sis.c (revision 9a14aa017b21c292740c00ee098195cd46642730)
1 /*-
2  * Copyright (c) 2005 Poul-Henning Kamp <phk@FreeBSD.org>
3  * Copyright (c) 1997, 1998, 1999
4  *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by Bill Paul.
17  * 4. Neither the name of the author nor the names of any co-contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
31  * THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 /*
38  * SiS 900/SiS 7016 fast ethernet PCI NIC driver. Datasheets are
39  * available from http://www.sis.com.tw.
40  *
41  * This driver also supports the NatSemi DP83815. Datasheets are
42  * available from http://www.national.com.
43  *
44  * Written by Bill Paul <wpaul@ee.columbia.edu>
45  * Electrical Engineering Department
46  * Columbia University, New York City
47  */
48 /*
49  * The SiS 900 is a fairly simple chip. It uses bus master DMA with
50  * simple TX and RX descriptors of 3 longwords in size. The receiver
51  * has a single perfect filter entry for the station address and a
52  * 128-bit multicast hash table. The SiS 900 has a built-in MII-based
53  * transceiver while the 7016 requires an external transceiver chip.
54  * Both chips offer the standard bit-bang MII interface as well as
55  * an enchanced PHY interface which simplifies accessing MII registers.
56  *
57  * The only downside to this chipset is that RX descriptors must be
58  * longword aligned.
59  */
60 
61 #ifdef HAVE_KERNEL_OPTION_HEADERS
62 #include "opt_device_polling.h"
63 #endif
64 
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/bus.h>
68 #include <sys/endian.h>
69 #include <sys/kernel.h>
70 #include <sys/lock.h>
71 #include <sys/malloc.h>
72 #include <sys/mbuf.h>
73 #include <sys/module.h>
74 #include <sys/socket.h>
75 #include <sys/sockio.h>
76 #include <sys/sysctl.h>
77 
78 #include <net/if.h>
79 #include <net/if_arp.h>
80 #include <net/ethernet.h>
81 #include <net/if_dl.h>
82 #include <net/if_media.h>
83 #include <net/if_types.h>
84 #include <net/if_vlan_var.h>
85 
86 #include <net/bpf.h>
87 
88 #include <machine/bus.h>
89 #include <machine/resource.h>
90 #include <sys/rman.h>
91 
92 #include <dev/mii/mii.h>
93 #include <dev/mii/mii_bitbang.h>
94 #include <dev/mii/miivar.h>
95 
96 #include <dev/pci/pcireg.h>
97 #include <dev/pci/pcivar.h>
98 
99 #define SIS_USEIOSPACE
100 
101 #include <dev/sis/if_sisreg.h>
102 
103 MODULE_DEPEND(sis, pci, 1, 1, 1);
104 MODULE_DEPEND(sis, ether, 1, 1, 1);
105 MODULE_DEPEND(sis, miibus, 1, 1, 1);
106 
107 /* "device miibus" required.  See GENERIC if you get errors here. */
108 #include "miibus_if.h"
109 
110 #define	SIS_LOCK(_sc)		mtx_lock(&(_sc)->sis_mtx)
111 #define	SIS_UNLOCK(_sc)		mtx_unlock(&(_sc)->sis_mtx)
112 #define	SIS_LOCK_ASSERT(_sc)	mtx_assert(&(_sc)->sis_mtx, MA_OWNED)
113 
114 /*
115  * register space access macros
116  */
117 #define CSR_WRITE_4(sc, reg, val)	bus_write_4(sc->sis_res[0], reg, val)
118 
119 #define CSR_READ_4(sc, reg)		bus_read_4(sc->sis_res[0], reg)
120 
121 #define CSR_READ_2(sc, reg)		bus_read_2(sc->sis_res[0], reg)
122 
123 #define	CSR_BARRIER(sc, reg, length, flags)				\
124 	bus_barrier(sc->sis_res[0], reg, length, flags)
125 
126 /*
127  * Various supported device vendors/types and their names.
128  */
129 static const struct sis_type const sis_devs[] = {
130 	{ SIS_VENDORID, SIS_DEVICEID_900, "SiS 900 10/100BaseTX" },
131 	{ SIS_VENDORID, SIS_DEVICEID_7016, "SiS 7016 10/100BaseTX" },
132 	{ NS_VENDORID, NS_DEVICEID_DP83815, "NatSemi DP8381[56] 10/100BaseTX" },
133 	{ 0, 0, NULL }
134 };
135 
136 static int sis_detach(device_t);
137 static __inline void sis_discard_rxbuf(struct sis_rxdesc *);
138 static int sis_dma_alloc(struct sis_softc *);
139 static void sis_dma_free(struct sis_softc *);
140 static int sis_dma_ring_alloc(struct sis_softc *, bus_size_t, bus_size_t,
141     bus_dma_tag_t *, uint8_t **, bus_dmamap_t *, bus_addr_t *, const char *);
142 static void sis_dmamap_cb(void *, bus_dma_segment_t *, int, int);
143 #ifndef __NO_STRICT_ALIGNMENT
144 static __inline void sis_fixup_rx(struct mbuf *);
145 #endif
146 static void sis_ifmedia_sts(struct ifnet *, struct ifmediareq *);
147 static int sis_ifmedia_upd(struct ifnet *);
148 static void sis_init(void *);
149 static void sis_initl(struct sis_softc *);
150 static void sis_intr(void *);
151 static int sis_ioctl(struct ifnet *, u_long, caddr_t);
152 static uint32_t sis_mii_bitbang_read(device_t);
153 static void sis_mii_bitbang_write(device_t, uint32_t);
154 static int sis_newbuf(struct sis_softc *, struct sis_rxdesc *);
155 static int sis_resume(device_t);
156 static int sis_rxeof(struct sis_softc *);
157 static void sis_rxfilter(struct sis_softc *);
158 static void sis_rxfilter_ns(struct sis_softc *);
159 static void sis_rxfilter_sis(struct sis_softc *);
160 static void sis_start(struct ifnet *);
161 static void sis_startl(struct ifnet *);
162 static void sis_stop(struct sis_softc *);
163 static int sis_suspend(device_t);
164 static void sis_add_sysctls(struct sis_softc *);
165 static void sis_watchdog(struct sis_softc *);
166 static void sis_wol(struct sis_softc *);
167 
168 /*
169  * MII bit-bang glue
170  */
171 static const struct mii_bitbang_ops sis_mii_bitbang_ops = {
172 	sis_mii_bitbang_read,
173 	sis_mii_bitbang_write,
174 	{
175 		SIS_MII_DATA,		/* MII_BIT_MDO */
176 		SIS_MII_DATA,		/* MII_BIT_MDI */
177 		SIS_MII_CLK,		/* MII_BIT_MDC */
178 		SIS_MII_DIR,		/* MII_BIT_DIR_HOST_PHY */
179 		0,			/* MII_BIT_DIR_PHY_HOST */
180 	}
181 };
182 
183 static struct resource_spec sis_res_spec[] = {
184 #ifdef SIS_USEIOSPACE
185 	{ SYS_RES_IOPORT,	SIS_PCI_LOIO,	RF_ACTIVE},
186 #else
187 	{ SYS_RES_MEMORY,	SIS_PCI_LOMEM,	RF_ACTIVE},
188 #endif
189 	{ SYS_RES_IRQ,		0,		RF_ACTIVE | RF_SHAREABLE},
190 	{ -1, 0 }
191 };
192 
193 #define SIS_SETBIT(sc, reg, x)				\
194 	CSR_WRITE_4(sc, reg,				\
195 		CSR_READ_4(sc, reg) | (x))
196 
197 #define SIS_CLRBIT(sc, reg, x)				\
198 	CSR_WRITE_4(sc, reg,				\
199 		CSR_READ_4(sc, reg) & ~(x))
200 
201 #define SIO_SET(x)					\
202 	CSR_WRITE_4(sc, SIS_EECTL, CSR_READ_4(sc, SIS_EECTL) | x)
203 
204 #define SIO_CLR(x)					\
205 	CSR_WRITE_4(sc, SIS_EECTL, CSR_READ_4(sc, SIS_EECTL) & ~x)
206 
207 /*
208  * Routine to reverse the bits in a word. Stolen almost
209  * verbatim from /usr/games/fortune.
210  */
211 static uint16_t
212 sis_reverse(uint16_t n)
213 {
214 	n = ((n >>  1) & 0x5555) | ((n <<  1) & 0xaaaa);
215 	n = ((n >>  2) & 0x3333) | ((n <<  2) & 0xcccc);
216 	n = ((n >>  4) & 0x0f0f) | ((n <<  4) & 0xf0f0);
217 	n = ((n >>  8) & 0x00ff) | ((n <<  8) & 0xff00);
218 
219 	return (n);
220 }
221 
222 static void
223 sis_delay(struct sis_softc *sc)
224 {
225 	int			idx;
226 
227 	for (idx = (300 / 33) + 1; idx > 0; idx--)
228 		CSR_READ_4(sc, SIS_CSR);
229 }
230 
231 static void
232 sis_eeprom_idle(struct sis_softc *sc)
233 {
234 	int		i;
235 
236 	SIO_SET(SIS_EECTL_CSEL);
237 	sis_delay(sc);
238 	SIO_SET(SIS_EECTL_CLK);
239 	sis_delay(sc);
240 
241 	for (i = 0; i < 25; i++) {
242 		SIO_CLR(SIS_EECTL_CLK);
243 		sis_delay(sc);
244 		SIO_SET(SIS_EECTL_CLK);
245 		sis_delay(sc);
246 	}
247 
248 	SIO_CLR(SIS_EECTL_CLK);
249 	sis_delay(sc);
250 	SIO_CLR(SIS_EECTL_CSEL);
251 	sis_delay(sc);
252 	CSR_WRITE_4(sc, SIS_EECTL, 0x00000000);
253 }
254 
255 /*
256  * Send a read command and address to the EEPROM, check for ACK.
257  */
258 static void
259 sis_eeprom_putbyte(struct sis_softc *sc, int addr)
260 {
261 	int		d, i;
262 
263 	d = addr | SIS_EECMD_READ;
264 
265 	/*
266 	 * Feed in each bit and stobe the clock.
267 	 */
268 	for (i = 0x400; i; i >>= 1) {
269 		if (d & i) {
270 			SIO_SET(SIS_EECTL_DIN);
271 		} else {
272 			SIO_CLR(SIS_EECTL_DIN);
273 		}
274 		sis_delay(sc);
275 		SIO_SET(SIS_EECTL_CLK);
276 		sis_delay(sc);
277 		SIO_CLR(SIS_EECTL_CLK);
278 		sis_delay(sc);
279 	}
280 }
281 
282 /*
283  * Read a word of data stored in the EEPROM at address 'addr.'
284  */
285 static void
286 sis_eeprom_getword(struct sis_softc *sc, int addr, uint16_t *dest)
287 {
288 	int		i;
289 	uint16_t	word = 0;
290 
291 	/* Force EEPROM to idle state. */
292 	sis_eeprom_idle(sc);
293 
294 	/* Enter EEPROM access mode. */
295 	sis_delay(sc);
296 	SIO_CLR(SIS_EECTL_CLK);
297 	sis_delay(sc);
298 	SIO_SET(SIS_EECTL_CSEL);
299 	sis_delay(sc);
300 
301 	/*
302 	 * Send address of word we want to read.
303 	 */
304 	sis_eeprom_putbyte(sc, addr);
305 
306 	/*
307 	 * Start reading bits from EEPROM.
308 	 */
309 	for (i = 0x8000; i; i >>= 1) {
310 		SIO_SET(SIS_EECTL_CLK);
311 		sis_delay(sc);
312 		if (CSR_READ_4(sc, SIS_EECTL) & SIS_EECTL_DOUT)
313 			word |= i;
314 		sis_delay(sc);
315 		SIO_CLR(SIS_EECTL_CLK);
316 		sis_delay(sc);
317 	}
318 
319 	/* Turn off EEPROM access mode. */
320 	sis_eeprom_idle(sc);
321 
322 	*dest = word;
323 }
324 
325 /*
326  * Read a sequence of words from the EEPROM.
327  */
328 static void
329 sis_read_eeprom(struct sis_softc *sc, caddr_t dest, int off, int cnt, int swap)
330 {
331 	int			i;
332 	uint16_t		word = 0, *ptr;
333 
334 	for (i = 0; i < cnt; i++) {
335 		sis_eeprom_getword(sc, off + i, &word);
336 		ptr = (uint16_t *)(dest + (i * 2));
337 		if (swap)
338 			*ptr = ntohs(word);
339 		else
340 			*ptr = word;
341 	}
342 }
343 
344 #if defined(__i386__) || defined(__amd64__)
345 static device_t
346 sis_find_bridge(device_t dev)
347 {
348 	devclass_t		pci_devclass;
349 	device_t		*pci_devices;
350 	int			pci_count = 0;
351 	device_t		*pci_children;
352 	int			pci_childcount = 0;
353 	device_t		*busp, *childp;
354 	device_t		child = NULL;
355 	int			i, j;
356 
357 	if ((pci_devclass = devclass_find("pci")) == NULL)
358 		return (NULL);
359 
360 	devclass_get_devices(pci_devclass, &pci_devices, &pci_count);
361 
362 	for (i = 0, busp = pci_devices; i < pci_count; i++, busp++) {
363 		if (device_get_children(*busp, &pci_children, &pci_childcount))
364 			continue;
365 		for (j = 0, childp = pci_children;
366 		    j < pci_childcount; j++, childp++) {
367 			if (pci_get_vendor(*childp) == SIS_VENDORID &&
368 			    pci_get_device(*childp) == 0x0008) {
369 				child = *childp;
370 				free(pci_children, M_TEMP);
371 				goto done;
372 			}
373 		}
374 		free(pci_children, M_TEMP);
375 	}
376 
377 done:
378 	free(pci_devices, M_TEMP);
379 	return (child);
380 }
381 
382 static void
383 sis_read_cmos(struct sis_softc *sc, device_t dev, caddr_t dest, int off, int cnt)
384 {
385 	device_t		bridge;
386 	uint8_t			reg;
387 	int			i;
388 	bus_space_tag_t		btag;
389 
390 	bridge = sis_find_bridge(dev);
391 	if (bridge == NULL)
392 		return;
393 	reg = pci_read_config(bridge, 0x48, 1);
394 	pci_write_config(bridge, 0x48, reg|0x40, 1);
395 
396 	/* XXX */
397 #if defined(__amd64__) || defined(__i386__)
398 	btag = X86_BUS_SPACE_IO;
399 #endif
400 
401 	for (i = 0; i < cnt; i++) {
402 		bus_space_write_1(btag, 0x0, 0x70, i + off);
403 		*(dest + i) = bus_space_read_1(btag, 0x0, 0x71);
404 	}
405 
406 	pci_write_config(bridge, 0x48, reg & ~0x40, 1);
407 }
408 
409 static void
410 sis_read_mac(struct sis_softc *sc, device_t dev, caddr_t dest)
411 {
412 	uint32_t		filtsave, csrsave;
413 
414 	filtsave = CSR_READ_4(sc, SIS_RXFILT_CTL);
415 	csrsave = CSR_READ_4(sc, SIS_CSR);
416 
417 	CSR_WRITE_4(sc, SIS_CSR, SIS_CSR_RELOAD | filtsave);
418 	CSR_WRITE_4(sc, SIS_CSR, 0);
419 
420 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filtsave & ~SIS_RXFILTCTL_ENABLE);
421 
422 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR0);
423 	((uint16_t *)dest)[0] = CSR_READ_2(sc, SIS_RXFILT_DATA);
424 	CSR_WRITE_4(sc, SIS_RXFILT_CTL,SIS_FILTADDR_PAR1);
425 	((uint16_t *)dest)[1] = CSR_READ_2(sc, SIS_RXFILT_DATA);
426 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR2);
427 	((uint16_t *)dest)[2] = CSR_READ_2(sc, SIS_RXFILT_DATA);
428 
429 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filtsave);
430 	CSR_WRITE_4(sc, SIS_CSR, csrsave);
431 }
432 #endif
433 
434 /*
435  * Read the MII serial port for the MII bit-bang module.
436  */
437 static uint32_t
438 sis_mii_bitbang_read(device_t dev)
439 {
440 	struct sis_softc	*sc;
441 	uint32_t		val;
442 
443 	sc = device_get_softc(dev);
444 
445 	val = CSR_READ_4(sc, SIS_EECTL);
446 	CSR_BARRIER(sc, SIS_EECTL, 4,
447 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
448 	return (val);
449 }
450 
451 /*
452  * Write the MII serial port for the MII bit-bang module.
453  */
454 static void
455 sis_mii_bitbang_write(device_t dev, uint32_t val)
456 {
457 	struct sis_softc	*sc;
458 
459 	sc = device_get_softc(dev);
460 
461 	CSR_WRITE_4(sc, SIS_EECTL, val);
462 	CSR_BARRIER(sc, SIS_EECTL, 4,
463 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
464 }
465 
466 static int
467 sis_miibus_readreg(device_t dev, int phy, int reg)
468 {
469 	struct sis_softc	*sc;
470 
471 	sc = device_get_softc(dev);
472 
473 	if (sc->sis_type == SIS_TYPE_83815) {
474 		if (phy != 0)
475 			return (0);
476 		/*
477 		 * The NatSemi chip can take a while after
478 		 * a reset to come ready, during which the BMSR
479 		 * returns a value of 0. This is *never* supposed
480 		 * to happen: some of the BMSR bits are meant to
481 		 * be hardwired in the on position, and this can
482 		 * confuse the miibus code a bit during the probe
483 		 * and attach phase. So we make an effort to check
484 		 * for this condition and wait for it to clear.
485 		 */
486 		if (!CSR_READ_4(sc, NS_BMSR))
487 			DELAY(1000);
488 		return CSR_READ_4(sc, NS_BMCR + (reg * 4));
489 	}
490 
491 	/*
492 	 * Chipsets < SIS_635 seem not to be able to read/write
493 	 * through mdio. Use the enhanced PHY access register
494 	 * again for them.
495 	 */
496 	if (sc->sis_type == SIS_TYPE_900 &&
497 	    sc->sis_rev < SIS_REV_635) {
498 		int i, val = 0;
499 
500 		if (phy != 0)
501 			return (0);
502 
503 		CSR_WRITE_4(sc, SIS_PHYCTL,
504 		    (phy << 11) | (reg << 6) | SIS_PHYOP_READ);
505 		SIS_SETBIT(sc, SIS_PHYCTL, SIS_PHYCTL_ACCESS);
506 
507 		for (i = 0; i < SIS_TIMEOUT; i++) {
508 			if (!(CSR_READ_4(sc, SIS_PHYCTL) & SIS_PHYCTL_ACCESS))
509 				break;
510 		}
511 
512 		if (i == SIS_TIMEOUT) {
513 			device_printf(sc->sis_dev,
514 			    "PHY failed to come ready\n");
515 			return (0);
516 		}
517 
518 		val = (CSR_READ_4(sc, SIS_PHYCTL) >> 16) & 0xFFFF;
519 
520 		if (val == 0xFFFF)
521 			return (0);
522 
523 		return (val);
524 	} else
525 		return (mii_bitbang_readreg(dev, &sis_mii_bitbang_ops, phy,
526 		    reg));
527 }
528 
529 static int
530 sis_miibus_writereg(device_t dev, int phy, int reg, int data)
531 {
532 	struct sis_softc	*sc;
533 
534 	sc = device_get_softc(dev);
535 
536 	if (sc->sis_type == SIS_TYPE_83815) {
537 		if (phy != 0)
538 			return (0);
539 		CSR_WRITE_4(sc, NS_BMCR + (reg * 4), data);
540 		return (0);
541 	}
542 
543 	/*
544 	 * Chipsets < SIS_635 seem not to be able to read/write
545 	 * through mdio. Use the enhanced PHY access register
546 	 * again for them.
547 	 */
548 	if (sc->sis_type == SIS_TYPE_900 &&
549 	    sc->sis_rev < SIS_REV_635) {
550 		int i;
551 
552 		if (phy != 0)
553 			return (0);
554 
555 		CSR_WRITE_4(sc, SIS_PHYCTL, (data << 16) | (phy << 11) |
556 		    (reg << 6) | SIS_PHYOP_WRITE);
557 		SIS_SETBIT(sc, SIS_PHYCTL, SIS_PHYCTL_ACCESS);
558 
559 		for (i = 0; i < SIS_TIMEOUT; i++) {
560 			if (!(CSR_READ_4(sc, SIS_PHYCTL) & SIS_PHYCTL_ACCESS))
561 				break;
562 		}
563 
564 		if (i == SIS_TIMEOUT)
565 			device_printf(sc->sis_dev,
566 			    "PHY failed to come ready\n");
567 	} else
568 		mii_bitbang_writereg(dev, &sis_mii_bitbang_ops, phy, reg,
569 		    data);
570 	return (0);
571 }
572 
573 static void
574 sis_miibus_statchg(device_t dev)
575 {
576 	struct sis_softc	*sc;
577 	struct mii_data		*mii;
578 	struct ifnet		*ifp;
579 	uint32_t		reg;
580 
581 	sc = device_get_softc(dev);
582 	SIS_LOCK_ASSERT(sc);
583 
584 	mii = device_get_softc(sc->sis_miibus);
585 	ifp = sc->sis_ifp;
586 	if (mii == NULL || ifp == NULL ||
587 	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
588 		return;
589 
590 	sc->sis_flags &= ~SIS_FLAG_LINK;
591 	if ((mii->mii_media_status & (IFM_ACTIVE | IFM_AVALID)) ==
592 	    (IFM_ACTIVE | IFM_AVALID)) {
593 		switch (IFM_SUBTYPE(mii->mii_media_active)) {
594 		case IFM_10_T:
595 			CSR_WRITE_4(sc, SIS_TX_CFG, SIS_TXCFG_10);
596 			sc->sis_flags |= SIS_FLAG_LINK;
597 			break;
598 		case IFM_100_TX:
599 			CSR_WRITE_4(sc, SIS_TX_CFG, SIS_TXCFG_100);
600 			sc->sis_flags |= SIS_FLAG_LINK;
601 			break;
602 		default:
603 			break;
604 		}
605 	}
606 
607 	if ((sc->sis_flags & SIS_FLAG_LINK) == 0) {
608 		/*
609 		 * Stopping MACs seem to reset SIS_TX_LISTPTR and
610 		 * SIS_RX_LISTPTR which in turn requires resetting
611 		 * TX/RX buffers.  So just don't do anything for
612 		 * lost link.
613 		 */
614 		return;
615 	}
616 
617 	/* Set full/half duplex mode. */
618 	if ((IFM_OPTIONS(mii->mii_media_active) & IFM_FDX) != 0) {
619 		SIS_SETBIT(sc, SIS_TX_CFG,
620 		    (SIS_TXCFG_IGN_HBEAT | SIS_TXCFG_IGN_CARR));
621 		SIS_SETBIT(sc, SIS_RX_CFG, SIS_RXCFG_RX_TXPKTS);
622 	} else {
623 		SIS_CLRBIT(sc, SIS_TX_CFG,
624 		    (SIS_TXCFG_IGN_HBEAT | SIS_TXCFG_IGN_CARR));
625 		SIS_CLRBIT(sc, SIS_RX_CFG, SIS_RXCFG_RX_TXPKTS);
626 	}
627 
628 	if (sc->sis_type == SIS_TYPE_83816) {
629 		/*
630 		 * MPII03.D: Half Duplex Excessive Collisions.
631 		 * Also page 49 in 83816 manual
632 		 */
633 		SIS_SETBIT(sc, SIS_TX_CFG, SIS_TXCFG_MPII03D);
634 	}
635 
636 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr < NS_SRR_16A &&
637 	    IFM_SUBTYPE(mii->mii_media_active) == IFM_100_TX) {
638 		/*
639 		 * Short Cable Receive Errors (MP21.E)
640 		 */
641 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0x0001);
642 		reg = CSR_READ_4(sc, NS_PHY_DSPCFG) & 0xfff;
643 		CSR_WRITE_4(sc, NS_PHY_DSPCFG, reg | 0x1000);
644 		DELAY(100);
645 		reg = CSR_READ_4(sc, NS_PHY_TDATA) & 0xff;
646 		if ((reg & 0x0080) == 0 || (reg > 0xd8 && reg <= 0xff)) {
647 			device_printf(sc->sis_dev,
648 			    "Applying short cable fix (reg=%x)\n", reg);
649 			CSR_WRITE_4(sc, NS_PHY_TDATA, 0x00e8);
650 			SIS_SETBIT(sc, NS_PHY_DSPCFG, 0x20);
651 		}
652 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0);
653 	}
654 	/* Enable TX/RX MACs. */
655 	SIS_CLRBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE | SIS_CSR_RX_DISABLE);
656 	SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_ENABLE | SIS_CSR_RX_ENABLE);
657 }
658 
659 static uint32_t
660 sis_mchash(struct sis_softc *sc, const uint8_t *addr)
661 {
662 	uint32_t		crc;
663 
664 	/* Compute CRC for the address value. */
665 	crc = ether_crc32_be(addr, ETHER_ADDR_LEN);
666 
667 	/*
668 	 * return the filter bit position
669 	 *
670 	 * The NatSemi chip has a 512-bit filter, which is
671 	 * different than the SiS, so we special-case it.
672 	 */
673 	if (sc->sis_type == SIS_TYPE_83815)
674 		return (crc >> 23);
675 	else if (sc->sis_rev >= SIS_REV_635 ||
676 	    sc->sis_rev == SIS_REV_900B)
677 		return (crc >> 24);
678 	else
679 		return (crc >> 25);
680 }
681 
682 static void
683 sis_rxfilter(struct sis_softc *sc)
684 {
685 
686 	SIS_LOCK_ASSERT(sc);
687 
688 	if (sc->sis_type == SIS_TYPE_83815)
689 		sis_rxfilter_ns(sc);
690 	else
691 		sis_rxfilter_sis(sc);
692 }
693 
694 static void
695 sis_rxfilter_ns(struct sis_softc *sc)
696 {
697 	struct ifnet		*ifp;
698 	struct ifmultiaddr	*ifma;
699 	uint32_t		h, i, filter;
700 	int			bit, index;
701 
702 	ifp = sc->sis_ifp;
703 	filter = CSR_READ_4(sc, SIS_RXFILT_CTL);
704 	if (filter & SIS_RXFILTCTL_ENABLE) {
705 		/*
706 		 * Filter should be disabled to program other bits.
707 		 */
708 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter & ~SIS_RXFILTCTL_ENABLE);
709 		CSR_READ_4(sc, SIS_RXFILT_CTL);
710 	}
711 	filter &= ~(NS_RXFILTCTL_ARP | NS_RXFILTCTL_PERFECT |
712 	    NS_RXFILTCTL_MCHASH | SIS_RXFILTCTL_ALLPHYS | SIS_RXFILTCTL_BROAD |
713 	    SIS_RXFILTCTL_ALLMULTI);
714 
715 	if (ifp->if_flags & IFF_BROADCAST)
716 		filter |= SIS_RXFILTCTL_BROAD;
717 	/*
718 	 * For the NatSemi chip, we have to explicitly enable the
719 	 * reception of ARP frames, as well as turn on the 'perfect
720 	 * match' filter where we store the station address, otherwise
721 	 * we won't receive unicasts meant for this host.
722 	 */
723 	filter |= NS_RXFILTCTL_ARP | NS_RXFILTCTL_PERFECT;
724 
725 	if (ifp->if_flags & (IFF_ALLMULTI | IFF_PROMISC)) {
726 		filter |= SIS_RXFILTCTL_ALLMULTI;
727 		if (ifp->if_flags & IFF_PROMISC)
728 			filter |= SIS_RXFILTCTL_ALLPHYS;
729 	} else {
730 		/*
731 		 * We have to explicitly enable the multicast hash table
732 		 * on the NatSemi chip if we want to use it, which we do.
733 		 */
734 		filter |= NS_RXFILTCTL_MCHASH;
735 
736 		/* first, zot all the existing hash bits */
737 		for (i = 0; i < 32; i++) {
738 			CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_FMEM_LO +
739 			    (i * 2));
740 			CSR_WRITE_4(sc, SIS_RXFILT_DATA, 0);
741 		}
742 
743 		if_maddr_rlock(ifp);
744 		TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
745 			if (ifma->ifma_addr->sa_family != AF_LINK)
746 				continue;
747 			h = sis_mchash(sc,
748 			    LLADDR((struct sockaddr_dl *)ifma->ifma_addr));
749 			index = h >> 3;
750 			bit = h & 0x1F;
751 			CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_FMEM_LO +
752 			    index);
753 			if (bit > 0xF)
754 				bit -= 0x10;
755 			SIS_SETBIT(sc, SIS_RXFILT_DATA, (1 << bit));
756 		}
757 		if_maddr_runlock(ifp);
758 	}
759 
760 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter);
761 	CSR_READ_4(sc, SIS_RXFILT_CTL);
762 }
763 
764 static void
765 sis_rxfilter_sis(struct sis_softc *sc)
766 {
767 	struct ifnet		*ifp;
768 	struct ifmultiaddr	*ifma;
769 	uint32_t		filter, h, i, n;
770 	uint16_t		hashes[16];
771 
772 	ifp = sc->sis_ifp;
773 
774 	/* hash table size */
775 	if (sc->sis_rev >= SIS_REV_635 || sc->sis_rev == SIS_REV_900B)
776 		n = 16;
777 	else
778 		n = 8;
779 
780 	filter = CSR_READ_4(sc, SIS_RXFILT_CTL);
781 	if (filter & SIS_RXFILTCTL_ENABLE) {
782 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter & ~SIS_RXFILT_CTL);
783 		CSR_READ_4(sc, SIS_RXFILT_CTL);
784 	}
785 	filter &= ~(SIS_RXFILTCTL_ALLPHYS | SIS_RXFILTCTL_BROAD |
786 	    SIS_RXFILTCTL_ALLMULTI);
787 	if (ifp->if_flags & IFF_BROADCAST)
788 		filter |= SIS_RXFILTCTL_BROAD;
789 
790 	if (ifp->if_flags & (IFF_ALLMULTI | IFF_PROMISC)) {
791 		filter |= SIS_RXFILTCTL_ALLMULTI;
792 		if (ifp->if_flags & IFF_PROMISC)
793 			filter |= SIS_RXFILTCTL_ALLPHYS;
794 		for (i = 0; i < n; i++)
795 			hashes[i] = ~0;
796 	} else {
797 		for (i = 0; i < n; i++)
798 			hashes[i] = 0;
799 		i = 0;
800 		if_maddr_rlock(ifp);
801 		TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
802 			if (ifma->ifma_addr->sa_family != AF_LINK)
803 			continue;
804 			h = sis_mchash(sc,
805 			    LLADDR((struct sockaddr_dl *)ifma->ifma_addr));
806 			hashes[h >> 4] |= 1 << (h & 0xf);
807 			i++;
808 		}
809 		if_maddr_runlock(ifp);
810 		if (i > n) {
811 			filter |= SIS_RXFILTCTL_ALLMULTI;
812 			for (i = 0; i < n; i++)
813 				hashes[i] = ~0;
814 		}
815 	}
816 
817 	for (i = 0; i < n; i++) {
818 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, (4 + i) << 16);
819 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, hashes[i]);
820 	}
821 
822 	CSR_WRITE_4(sc, SIS_RXFILT_CTL, filter);
823 	CSR_READ_4(sc, SIS_RXFILT_CTL);
824 }
825 
826 static void
827 sis_reset(struct sis_softc *sc)
828 {
829 	int		i;
830 
831 	SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RESET);
832 
833 	for (i = 0; i < SIS_TIMEOUT; i++) {
834 		if (!(CSR_READ_4(sc, SIS_CSR) & SIS_CSR_RESET))
835 			break;
836 	}
837 
838 	if (i == SIS_TIMEOUT)
839 		device_printf(sc->sis_dev, "reset never completed\n");
840 
841 	/* Wait a little while for the chip to get its brains in order. */
842 	DELAY(1000);
843 
844 	/*
845 	 * If this is a NetSemi chip, make sure to clear
846 	 * PME mode.
847 	 */
848 	if (sc->sis_type == SIS_TYPE_83815) {
849 		CSR_WRITE_4(sc, NS_CLKRUN, NS_CLKRUN_PMESTS);
850 		CSR_WRITE_4(sc, NS_CLKRUN, 0);
851 	} else {
852 		/* Disable WOL functions. */
853 		CSR_WRITE_4(sc, SIS_PWRMAN_CTL, 0);
854 	}
855 }
856 
857 /*
858  * Probe for an SiS chip. Check the PCI vendor and device
859  * IDs against our list and return a device name if we find a match.
860  */
861 static int
862 sis_probe(device_t dev)
863 {
864 	const struct sis_type	*t;
865 
866 	t = sis_devs;
867 
868 	while (t->sis_name != NULL) {
869 		if ((pci_get_vendor(dev) == t->sis_vid) &&
870 		    (pci_get_device(dev) == t->sis_did)) {
871 			device_set_desc(dev, t->sis_name);
872 			return (BUS_PROBE_DEFAULT);
873 		}
874 		t++;
875 	}
876 
877 	return (ENXIO);
878 }
879 
880 /*
881  * Attach the interface. Allocate softc structures, do ifmedia
882  * setup and ethernet/BPF attach.
883  */
884 static int
885 sis_attach(device_t dev)
886 {
887 	u_char			eaddr[ETHER_ADDR_LEN];
888 	struct sis_softc	*sc;
889 	struct ifnet		*ifp;
890 	int			error = 0, pmc, waittime = 0;
891 
892 	waittime = 0;
893 	sc = device_get_softc(dev);
894 
895 	sc->sis_dev = dev;
896 
897 	mtx_init(&sc->sis_mtx, device_get_nameunit(dev), MTX_NETWORK_LOCK,
898 	    MTX_DEF);
899 	callout_init_mtx(&sc->sis_stat_ch, &sc->sis_mtx, 0);
900 
901 	if (pci_get_device(dev) == SIS_DEVICEID_900)
902 		sc->sis_type = SIS_TYPE_900;
903 	if (pci_get_device(dev) == SIS_DEVICEID_7016)
904 		sc->sis_type = SIS_TYPE_7016;
905 	if (pci_get_vendor(dev) == NS_VENDORID)
906 		sc->sis_type = SIS_TYPE_83815;
907 
908 	sc->sis_rev = pci_read_config(dev, PCIR_REVID, 1);
909 	/*
910 	 * Map control/status registers.
911 	 */
912 	pci_enable_busmaster(dev);
913 
914 	error = bus_alloc_resources(dev, sis_res_spec, sc->sis_res);
915 	if (error) {
916 		device_printf(dev, "couldn't allocate resources\n");
917 		goto fail;
918 	}
919 
920 	/* Reset the adapter. */
921 	sis_reset(sc);
922 
923 	if (sc->sis_type == SIS_TYPE_900 &&
924 	    (sc->sis_rev == SIS_REV_635 ||
925 	    sc->sis_rev == SIS_REV_900B)) {
926 		SIO_SET(SIS_CFG_RND_CNT);
927 		SIO_SET(SIS_CFG_PERR_DETECT);
928 	}
929 
930 	/*
931 	 * Get station address from the EEPROM.
932 	 */
933 	switch (pci_get_vendor(dev)) {
934 	case NS_VENDORID:
935 		sc->sis_srr = CSR_READ_4(sc, NS_SRR);
936 
937 		/* We can't update the device description, so spew */
938 		if (sc->sis_srr == NS_SRR_15C)
939 			device_printf(dev, "Silicon Revision: DP83815C\n");
940 		else if (sc->sis_srr == NS_SRR_15D)
941 			device_printf(dev, "Silicon Revision: DP83815D\n");
942 		else if (sc->sis_srr == NS_SRR_16A)
943 			device_printf(dev, "Silicon Revision: DP83816A\n");
944 		else
945 			device_printf(dev, "Silicon Revision %x\n", sc->sis_srr);
946 
947 		/*
948 		 * Reading the MAC address out of the EEPROM on
949 		 * the NatSemi chip takes a bit more work than
950 		 * you'd expect. The address spans 4 16-bit words,
951 		 * with the first word containing only a single bit.
952 		 * You have to shift everything over one bit to
953 		 * get it aligned properly. Also, the bits are
954 		 * stored backwards (the LSB is really the MSB,
955 		 * and so on) so you have to reverse them in order
956 		 * to get the MAC address into the form we want.
957 		 * Why? Who the hell knows.
958 		 */
959 		{
960 			uint16_t		tmp[4];
961 
962 			sis_read_eeprom(sc, (caddr_t)&tmp,
963 			    NS_EE_NODEADDR, 4, 0);
964 
965 			/* Shift everything over one bit. */
966 			tmp[3] = tmp[3] >> 1;
967 			tmp[3] |= tmp[2] << 15;
968 			tmp[2] = tmp[2] >> 1;
969 			tmp[2] |= tmp[1] << 15;
970 			tmp[1] = tmp[1] >> 1;
971 			tmp[1] |= tmp[0] << 15;
972 
973 			/* Now reverse all the bits. */
974 			tmp[3] = sis_reverse(tmp[3]);
975 			tmp[2] = sis_reverse(tmp[2]);
976 			tmp[1] = sis_reverse(tmp[1]);
977 
978 			eaddr[0] = (tmp[1] >> 0) & 0xFF;
979 			eaddr[1] = (tmp[1] >> 8) & 0xFF;
980 			eaddr[2] = (tmp[2] >> 0) & 0xFF;
981 			eaddr[3] = (tmp[2] >> 8) & 0xFF;
982 			eaddr[4] = (tmp[3] >> 0) & 0xFF;
983 			eaddr[5] = (tmp[3] >> 8) & 0xFF;
984 		}
985 		break;
986 	case SIS_VENDORID:
987 	default:
988 #if defined(__i386__) || defined(__amd64__)
989 		/*
990 		 * If this is a SiS 630E chipset with an embedded
991 		 * SiS 900 controller, we have to read the MAC address
992 		 * from the APC CMOS RAM. Our method for doing this
993 		 * is very ugly since we have to reach out and grab
994 		 * ahold of hardware for which we cannot properly
995 		 * allocate resources. This code is only compiled on
996 		 * the i386 architecture since the SiS 630E chipset
997 		 * is for x86 motherboards only. Note that there are
998 		 * a lot of magic numbers in this hack. These are
999 		 * taken from SiS's Linux driver. I'd like to replace
1000 		 * them with proper symbolic definitions, but that
1001 		 * requires some datasheets that I don't have access
1002 		 * to at the moment.
1003 		 */
1004 		if (sc->sis_rev == SIS_REV_630S ||
1005 		    sc->sis_rev == SIS_REV_630E ||
1006 		    sc->sis_rev == SIS_REV_630EA1)
1007 			sis_read_cmos(sc, dev, (caddr_t)&eaddr, 0x9, 6);
1008 
1009 		else if (sc->sis_rev == SIS_REV_635 ||
1010 			 sc->sis_rev == SIS_REV_630ET)
1011 			sis_read_mac(sc, dev, (caddr_t)&eaddr);
1012 		else if (sc->sis_rev == SIS_REV_96x) {
1013 			/* Allow to read EEPROM from LAN. It is shared
1014 			 * between a 1394 controller and the NIC and each
1015 			 * time we access it, we need to set SIS_EECMD_REQ.
1016 			 */
1017 			SIO_SET(SIS_EECMD_REQ);
1018 			for (waittime = 0; waittime < SIS_TIMEOUT;
1019 			    waittime++) {
1020 				/* Force EEPROM to idle state. */
1021 				sis_eeprom_idle(sc);
1022 				if (CSR_READ_4(sc, SIS_EECTL) & SIS_EECMD_GNT) {
1023 					sis_read_eeprom(sc, (caddr_t)&eaddr,
1024 					    SIS_EE_NODEADDR, 3, 0);
1025 					break;
1026 				}
1027 				DELAY(1);
1028 			}
1029 			/*
1030 			 * Set SIS_EECTL_CLK to high, so a other master
1031 			 * can operate on the i2c bus.
1032 			 */
1033 			SIO_SET(SIS_EECTL_CLK);
1034 			/* Refuse EEPROM access by LAN */
1035 			SIO_SET(SIS_EECMD_DONE);
1036 		} else
1037 #endif
1038 			sis_read_eeprom(sc, (caddr_t)&eaddr,
1039 			    SIS_EE_NODEADDR, 3, 0);
1040 		break;
1041 	}
1042 
1043 	sis_add_sysctls(sc);
1044 
1045 	/* Allocate DMA'able memory. */
1046 	if ((error = sis_dma_alloc(sc)) != 0)
1047 		goto fail;
1048 
1049 	ifp = sc->sis_ifp = if_alloc(IFT_ETHER);
1050 	if (ifp == NULL) {
1051 		device_printf(dev, "can not if_alloc()\n");
1052 		error = ENOSPC;
1053 		goto fail;
1054 	}
1055 	ifp->if_softc = sc;
1056 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
1057 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
1058 	ifp->if_ioctl = sis_ioctl;
1059 	ifp->if_start = sis_start;
1060 	ifp->if_init = sis_init;
1061 	IFQ_SET_MAXLEN(&ifp->if_snd, SIS_TX_LIST_CNT - 1);
1062 	ifp->if_snd.ifq_drv_maxlen = SIS_TX_LIST_CNT - 1;
1063 	IFQ_SET_READY(&ifp->if_snd);
1064 
1065 	if (pci_find_cap(sc->sis_dev, PCIY_PMG, &pmc) == 0) {
1066 		if (sc->sis_type == SIS_TYPE_83815)
1067 			ifp->if_capabilities |= IFCAP_WOL;
1068 		else
1069 			ifp->if_capabilities |= IFCAP_WOL_MAGIC;
1070 		ifp->if_capenable = ifp->if_capabilities;
1071 	}
1072 
1073 	/*
1074 	 * Do MII setup.
1075 	 */
1076 	error = mii_attach(dev, &sc->sis_miibus, ifp, sis_ifmedia_upd,
1077 	    sis_ifmedia_sts, BMSR_DEFCAPMASK, MII_PHY_ANY, MII_OFFSET_ANY, 0);
1078 	if (error != 0) {
1079 		device_printf(dev, "attaching PHYs failed\n");
1080 		goto fail;
1081 	}
1082 
1083 	/*
1084 	 * Call MI attach routine.
1085 	 */
1086 	ether_ifattach(ifp, eaddr);
1087 
1088 	/*
1089 	 * Tell the upper layer(s) we support long frames.
1090 	 */
1091 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
1092 	ifp->if_capabilities |= IFCAP_VLAN_MTU;
1093 	ifp->if_capenable = ifp->if_capabilities;
1094 #ifdef DEVICE_POLLING
1095 	ifp->if_capabilities |= IFCAP_POLLING;
1096 #endif
1097 
1098 	/* Hook interrupt last to avoid having to lock softc */
1099 	error = bus_setup_intr(dev, sc->sis_res[1], INTR_TYPE_NET | INTR_MPSAFE,
1100 	    NULL, sis_intr, sc, &sc->sis_intrhand);
1101 
1102 	if (error) {
1103 		device_printf(dev, "couldn't set up irq\n");
1104 		ether_ifdetach(ifp);
1105 		goto fail;
1106 	}
1107 
1108 fail:
1109 	if (error)
1110 		sis_detach(dev);
1111 
1112 	return (error);
1113 }
1114 
1115 /*
1116  * Shutdown hardware and free up resources. This can be called any
1117  * time after the mutex has been initialized. It is called in both
1118  * the error case in attach and the normal detach case so it needs
1119  * to be careful about only freeing resources that have actually been
1120  * allocated.
1121  */
1122 static int
1123 sis_detach(device_t dev)
1124 {
1125 	struct sis_softc	*sc;
1126 	struct ifnet		*ifp;
1127 
1128 	sc = device_get_softc(dev);
1129 	KASSERT(mtx_initialized(&sc->sis_mtx), ("sis mutex not initialized"));
1130 	ifp = sc->sis_ifp;
1131 
1132 #ifdef DEVICE_POLLING
1133 	if (ifp->if_capenable & IFCAP_POLLING)
1134 		ether_poll_deregister(ifp);
1135 #endif
1136 
1137 	/* These should only be active if attach succeeded. */
1138 	if (device_is_attached(dev)) {
1139 		SIS_LOCK(sc);
1140 		sis_stop(sc);
1141 		SIS_UNLOCK(sc);
1142 		callout_drain(&sc->sis_stat_ch);
1143 		ether_ifdetach(ifp);
1144 	}
1145 	if (sc->sis_miibus)
1146 		device_delete_child(dev, sc->sis_miibus);
1147 	bus_generic_detach(dev);
1148 
1149 	if (sc->sis_intrhand)
1150 		bus_teardown_intr(dev, sc->sis_res[1], sc->sis_intrhand);
1151 	bus_release_resources(dev, sis_res_spec, sc->sis_res);
1152 
1153 	if (ifp)
1154 		if_free(ifp);
1155 
1156 	sis_dma_free(sc);
1157 
1158 	mtx_destroy(&sc->sis_mtx);
1159 
1160 	return (0);
1161 }
1162 
1163 struct sis_dmamap_arg {
1164 	bus_addr_t	sis_busaddr;
1165 };
1166 
1167 static void
1168 sis_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
1169 {
1170 	struct sis_dmamap_arg	*ctx;
1171 
1172 	if (error != 0)
1173 		return;
1174 
1175 	KASSERT(nsegs == 1, ("%s: %d segments returned!", __func__, nsegs));
1176 
1177 	ctx = (struct sis_dmamap_arg *)arg;
1178 	ctx->sis_busaddr = segs[0].ds_addr;
1179 }
1180 
1181 static int
1182 sis_dma_ring_alloc(struct sis_softc *sc, bus_size_t alignment,
1183     bus_size_t maxsize, bus_dma_tag_t *tag, uint8_t **ring, bus_dmamap_t *map,
1184     bus_addr_t *paddr, const char *msg)
1185 {
1186 	struct sis_dmamap_arg	ctx;
1187 	int			error;
1188 
1189 	error = bus_dma_tag_create(sc->sis_parent_tag, alignment, 0,
1190 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, maxsize, 1,
1191 	    maxsize, 0, NULL, NULL, tag);
1192 	if (error != 0) {
1193 		device_printf(sc->sis_dev,
1194 		    "could not create %s dma tag\n", msg);
1195 		return (ENOMEM);
1196 	}
1197 	/* Allocate DMA'able memory for ring. */
1198 	error = bus_dmamem_alloc(*tag, (void **)ring,
1199 	    BUS_DMA_NOWAIT | BUS_DMA_ZERO | BUS_DMA_COHERENT, map);
1200 	if (error != 0) {
1201 		device_printf(sc->sis_dev,
1202 		    "could not allocate DMA'able memory for %s\n", msg);
1203 		return (ENOMEM);
1204 	}
1205 	/* Load the address of the ring. */
1206 	ctx.sis_busaddr = 0;
1207 	error = bus_dmamap_load(*tag, *map, *ring, maxsize, sis_dmamap_cb,
1208 	    &ctx, BUS_DMA_NOWAIT);
1209 	if (error != 0) {
1210 		device_printf(sc->sis_dev,
1211 		    "could not load DMA'able memory for %s\n", msg);
1212 		return (ENOMEM);
1213 	}
1214 	*paddr = ctx.sis_busaddr;
1215 	return (0);
1216 }
1217 
1218 static int
1219 sis_dma_alloc(struct sis_softc *sc)
1220 {
1221 	struct sis_rxdesc	*rxd;
1222 	struct sis_txdesc	*txd;
1223 	int			error, i;
1224 
1225 	/* Allocate the parent bus DMA tag appropriate for PCI. */
1226 	error = bus_dma_tag_create(bus_get_dma_tag(sc->sis_dev),
1227 	    1, 0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR, NULL,
1228 	    NULL, BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT,
1229 	    0, NULL, NULL, &sc->sis_parent_tag);
1230 	if (error != 0) {
1231 		device_printf(sc->sis_dev,
1232 		    "could not allocate parent dma tag\n");
1233 		return (ENOMEM);
1234 	}
1235 
1236 	/* Create RX ring. */
1237 	error = sis_dma_ring_alloc(sc, SIS_DESC_ALIGN, SIS_RX_LIST_SZ,
1238 	    &sc->sis_rx_list_tag, (uint8_t **)&sc->sis_rx_list,
1239 	    &sc->sis_rx_list_map, &sc->sis_rx_paddr, "RX ring");
1240 	if (error)
1241 		return (error);
1242 
1243 	/* Create TX ring. */
1244 	error = sis_dma_ring_alloc(sc, SIS_DESC_ALIGN, SIS_TX_LIST_SZ,
1245 	    &sc->sis_tx_list_tag, (uint8_t **)&sc->sis_tx_list,
1246 	    &sc->sis_tx_list_map, &sc->sis_tx_paddr, "TX ring");
1247 	if (error)
1248 		return (error);
1249 
1250 	/* Create tag for RX mbufs. */
1251 	error = bus_dma_tag_create(sc->sis_parent_tag, SIS_RX_BUF_ALIGN, 0,
1252 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, 1,
1253 	    MCLBYTES, 0, NULL, NULL, &sc->sis_rx_tag);
1254 	if (error) {
1255 		device_printf(sc->sis_dev, "could not allocate RX dma tag\n");
1256 		return (error);
1257 	}
1258 
1259 	/* Create tag for TX mbufs. */
1260 	error = bus_dma_tag_create(sc->sis_parent_tag, 1, 0,
1261 	    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
1262 	    MCLBYTES * SIS_MAXTXSEGS, SIS_MAXTXSEGS, MCLBYTES, 0, NULL, NULL,
1263 	    &sc->sis_tx_tag);
1264 	if (error) {
1265 		device_printf(sc->sis_dev, "could not allocate TX dma tag\n");
1266 		return (error);
1267 	}
1268 
1269 	/* Create DMA maps for RX buffers. */
1270 	error = bus_dmamap_create(sc->sis_rx_tag, 0, &sc->sis_rx_sparemap);
1271 	if (error) {
1272 		device_printf(sc->sis_dev,
1273 		    "can't create spare DMA map for RX\n");
1274 		return (error);
1275 	}
1276 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
1277 		rxd = &sc->sis_rxdesc[i];
1278 		rxd->rx_m = NULL;
1279 		error = bus_dmamap_create(sc->sis_rx_tag, 0, &rxd->rx_dmamap);
1280 		if (error) {
1281 			device_printf(sc->sis_dev,
1282 			    "can't create DMA map for RX\n");
1283 			return (error);
1284 		}
1285 	}
1286 
1287 	/* Create DMA maps for TX buffers. */
1288 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
1289 		txd = &sc->sis_txdesc[i];
1290 		txd->tx_m = NULL;
1291 		error = bus_dmamap_create(sc->sis_tx_tag, 0, &txd->tx_dmamap);
1292 		if (error) {
1293 			device_printf(sc->sis_dev,
1294 			    "can't create DMA map for TX\n");
1295 			return (error);
1296 		}
1297 	}
1298 
1299 	return (0);
1300 }
1301 
1302 static void
1303 sis_dma_free(struct sis_softc *sc)
1304 {
1305 	struct sis_rxdesc	*rxd;
1306 	struct sis_txdesc	*txd;
1307 	int			i;
1308 
1309 	/* Destroy DMA maps for RX buffers. */
1310 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
1311 		rxd = &sc->sis_rxdesc[i];
1312 		if (rxd->rx_dmamap)
1313 			bus_dmamap_destroy(sc->sis_rx_tag, rxd->rx_dmamap);
1314 	}
1315 	if (sc->sis_rx_sparemap)
1316 		bus_dmamap_destroy(sc->sis_rx_tag, sc->sis_rx_sparemap);
1317 
1318 	/* Destroy DMA maps for TX buffers. */
1319 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
1320 		txd = &sc->sis_txdesc[i];
1321 		if (txd->tx_dmamap)
1322 			bus_dmamap_destroy(sc->sis_tx_tag, txd->tx_dmamap);
1323 	}
1324 
1325 	if (sc->sis_rx_tag)
1326 		bus_dma_tag_destroy(sc->sis_rx_tag);
1327 	if (sc->sis_tx_tag)
1328 		bus_dma_tag_destroy(sc->sis_tx_tag);
1329 
1330 	/* Destroy RX ring. */
1331 	if (sc->sis_rx_list_map)
1332 		bus_dmamap_unload(sc->sis_rx_list_tag, sc->sis_rx_list_map);
1333 	if (sc->sis_rx_list_map && sc->sis_rx_list)
1334 		bus_dmamem_free(sc->sis_rx_list_tag, sc->sis_rx_list,
1335 		    sc->sis_rx_list_map);
1336 
1337 	if (sc->sis_rx_list_tag)
1338 		bus_dma_tag_destroy(sc->sis_rx_list_tag);
1339 
1340 	/* Destroy TX ring. */
1341 	if (sc->sis_tx_list_map)
1342 		bus_dmamap_unload(sc->sis_tx_list_tag, sc->sis_tx_list_map);
1343 
1344 	if (sc->sis_tx_list_map && sc->sis_tx_list)
1345 		bus_dmamem_free(sc->sis_tx_list_tag, sc->sis_tx_list,
1346 		    sc->sis_tx_list_map);
1347 
1348 	if (sc->sis_tx_list_tag)
1349 		bus_dma_tag_destroy(sc->sis_tx_list_tag);
1350 
1351 	/* Destroy the parent tag. */
1352 	if (sc->sis_parent_tag)
1353 		bus_dma_tag_destroy(sc->sis_parent_tag);
1354 }
1355 
1356 /*
1357  * Initialize the TX and RX descriptors and allocate mbufs for them. Note that
1358  * we arrange the descriptors in a closed ring, so that the last descriptor
1359  * points back to the first.
1360  */
1361 static int
1362 sis_ring_init(struct sis_softc *sc)
1363 {
1364 	struct sis_rxdesc	*rxd;
1365 	struct sis_txdesc	*txd;
1366 	bus_addr_t		next;
1367 	int			error, i;
1368 
1369 	bzero(&sc->sis_tx_list[0], SIS_TX_LIST_SZ);
1370 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
1371 		txd = &sc->sis_txdesc[i];
1372 		txd->tx_m = NULL;
1373 		if (i == SIS_TX_LIST_CNT - 1)
1374 			next = SIS_TX_RING_ADDR(sc, 0);
1375 		else
1376 			next = SIS_TX_RING_ADDR(sc, i + 1);
1377 		sc->sis_tx_list[i].sis_next = htole32(SIS_ADDR_LO(next));
1378 	}
1379 	sc->sis_tx_prod = sc->sis_tx_cons = sc->sis_tx_cnt = 0;
1380 	bus_dmamap_sync(sc->sis_tx_list_tag, sc->sis_tx_list_map,
1381 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1382 
1383 	sc->sis_rx_cons = 0;
1384 	bzero(&sc->sis_rx_list[0], SIS_RX_LIST_SZ);
1385 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
1386 		rxd = &sc->sis_rxdesc[i];
1387 		rxd->rx_desc = &sc->sis_rx_list[i];
1388 		if (i == SIS_RX_LIST_CNT - 1)
1389 			next = SIS_RX_RING_ADDR(sc, 0);
1390 		else
1391 			next = SIS_RX_RING_ADDR(sc, i + 1);
1392 		rxd->rx_desc->sis_next = htole32(SIS_ADDR_LO(next));
1393 		error = sis_newbuf(sc, rxd);
1394 		if (error)
1395 			return (error);
1396 	}
1397 	bus_dmamap_sync(sc->sis_rx_list_tag, sc->sis_rx_list_map,
1398 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1399 
1400 	return (0);
1401 }
1402 
1403 /*
1404  * Initialize an RX descriptor and attach an MBUF cluster.
1405  */
1406 static int
1407 sis_newbuf(struct sis_softc *sc, struct sis_rxdesc *rxd)
1408 {
1409 	struct mbuf		*m;
1410 	bus_dma_segment_t	segs[1];
1411 	bus_dmamap_t		map;
1412 	int nsegs;
1413 
1414 	m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
1415 	if (m == NULL)
1416 		return (ENOBUFS);
1417 	m->m_len = m->m_pkthdr.len = SIS_RXLEN;
1418 #ifndef __NO_STRICT_ALIGNMENT
1419 	m_adj(m, SIS_RX_BUF_ALIGN);
1420 #endif
1421 
1422 	if (bus_dmamap_load_mbuf_sg(sc->sis_rx_tag, sc->sis_rx_sparemap, m,
1423 	    segs, &nsegs, 0) != 0) {
1424 		m_freem(m);
1425 		return (ENOBUFS);
1426 	}
1427 	KASSERT(nsegs == 1, ("%s: %d segments returned!", __func__, nsegs));
1428 
1429 	if (rxd->rx_m != NULL) {
1430 		bus_dmamap_sync(sc->sis_rx_tag, rxd->rx_dmamap,
1431 		    BUS_DMASYNC_POSTREAD);
1432 		bus_dmamap_unload(sc->sis_rx_tag, rxd->rx_dmamap);
1433 	}
1434 	map = rxd->rx_dmamap;
1435 	rxd->rx_dmamap = sc->sis_rx_sparemap;
1436 	sc->sis_rx_sparemap = map;
1437 	bus_dmamap_sync(sc->sis_rx_tag, rxd->rx_dmamap, BUS_DMASYNC_PREREAD);
1438 	rxd->rx_m = m;
1439 	rxd->rx_desc->sis_ptr = htole32(SIS_ADDR_LO(segs[0].ds_addr));
1440 	rxd->rx_desc->sis_cmdsts = htole32(SIS_RXLEN);
1441 	return (0);
1442 }
1443 
1444 static __inline void
1445 sis_discard_rxbuf(struct sis_rxdesc *rxd)
1446 {
1447 
1448 	rxd->rx_desc->sis_cmdsts = htole32(SIS_RXLEN);
1449 }
1450 
1451 #ifndef __NO_STRICT_ALIGNMENT
1452 static __inline void
1453 sis_fixup_rx(struct mbuf *m)
1454 {
1455 	uint16_t		*src, *dst;
1456 	int			i;
1457 
1458 	src = mtod(m, uint16_t *);
1459 	dst = src - (SIS_RX_BUF_ALIGN - ETHER_ALIGN) / sizeof(*src);
1460 
1461 	for (i = 0; i < (m->m_len / sizeof(uint16_t) + 1); i++)
1462 		*dst++ = *src++;
1463 
1464 	m->m_data -= SIS_RX_BUF_ALIGN - ETHER_ALIGN;
1465 }
1466 #endif
1467 
1468 /*
1469  * A frame has been uploaded: pass the resulting mbuf chain up to
1470  * the higher level protocols.
1471  */
1472 static int
1473 sis_rxeof(struct sis_softc *sc)
1474 {
1475 	struct mbuf		*m;
1476 	struct ifnet		*ifp;
1477 	struct sis_rxdesc	*rxd;
1478 	struct sis_desc		*cur_rx;
1479 	int			prog, rx_cons, rx_npkts = 0, total_len;
1480 	uint32_t		rxstat;
1481 
1482 	SIS_LOCK_ASSERT(sc);
1483 
1484 	bus_dmamap_sync(sc->sis_rx_list_tag, sc->sis_rx_list_map,
1485 	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1486 
1487 	rx_cons = sc->sis_rx_cons;
1488 	ifp = sc->sis_ifp;
1489 
1490 	for (prog = 0; (ifp->if_drv_flags & IFF_DRV_RUNNING) != 0;
1491 	    SIS_INC(rx_cons, SIS_RX_LIST_CNT), prog++) {
1492 #ifdef DEVICE_POLLING
1493 		if (ifp->if_capenable & IFCAP_POLLING) {
1494 			if (sc->rxcycles <= 0)
1495 				break;
1496 			sc->rxcycles--;
1497 		}
1498 #endif
1499 		cur_rx = &sc->sis_rx_list[rx_cons];
1500 		rxstat = le32toh(cur_rx->sis_cmdsts);
1501 		if ((rxstat & SIS_CMDSTS_OWN) == 0)
1502 			break;
1503 		rxd = &sc->sis_rxdesc[rx_cons];
1504 
1505 		total_len = (rxstat & SIS_CMDSTS_BUFLEN) - ETHER_CRC_LEN;
1506 		if ((ifp->if_capenable & IFCAP_VLAN_MTU) != 0 &&
1507 		    total_len <= (ETHER_MAX_LEN + ETHER_VLAN_ENCAP_LEN -
1508 		    ETHER_CRC_LEN))
1509 			rxstat &= ~SIS_RXSTAT_GIANT;
1510 		if (SIS_RXSTAT_ERROR(rxstat) != 0) {
1511 			ifp->if_ierrors++;
1512 			if (rxstat & SIS_RXSTAT_COLL)
1513 				ifp->if_collisions++;
1514 			sis_discard_rxbuf(rxd);
1515 			continue;
1516 		}
1517 
1518 		/* Add a new receive buffer to the ring. */
1519 		m = rxd->rx_m;
1520 		if (sis_newbuf(sc, rxd) != 0) {
1521 			ifp->if_iqdrops++;
1522 			sis_discard_rxbuf(rxd);
1523 			continue;
1524 		}
1525 
1526 		/* No errors; receive the packet. */
1527 		m->m_pkthdr.len = m->m_len = total_len;
1528 #ifndef __NO_STRICT_ALIGNMENT
1529 		/*
1530 		 * On architectures without alignment problems we try to
1531 		 * allocate a new buffer for the receive ring, and pass up
1532 		 * the one where the packet is already, saving the expensive
1533 		 * copy operation.
1534 		 */
1535 		sis_fixup_rx(m);
1536 #endif
1537 		ifp->if_ipackets++;
1538 		m->m_pkthdr.rcvif = ifp;
1539 
1540 		SIS_UNLOCK(sc);
1541 		(*ifp->if_input)(ifp, m);
1542 		SIS_LOCK(sc);
1543 		rx_npkts++;
1544 	}
1545 
1546 	if (prog > 0) {
1547 		sc->sis_rx_cons = rx_cons;
1548 		bus_dmamap_sync(sc->sis_rx_list_tag, sc->sis_rx_list_map,
1549 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1550 	}
1551 
1552 	return (rx_npkts);
1553 }
1554 
1555 /*
1556  * A frame was downloaded to the chip. It's safe for us to clean up
1557  * the list buffers.
1558  */
1559 
1560 static void
1561 sis_txeof(struct sis_softc *sc)
1562 {
1563 	struct ifnet		*ifp;
1564 	struct sis_desc		*cur_tx;
1565 	struct sis_txdesc	*txd;
1566 	uint32_t		cons, txstat;
1567 
1568 	SIS_LOCK_ASSERT(sc);
1569 
1570 	cons = sc->sis_tx_cons;
1571 	if (cons == sc->sis_tx_prod)
1572 		return;
1573 
1574 	ifp = sc->sis_ifp;
1575 	bus_dmamap_sync(sc->sis_tx_list_tag, sc->sis_tx_list_map,
1576 	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
1577 
1578 	/*
1579 	 * Go through our tx list and free mbufs for those
1580 	 * frames that have been transmitted.
1581 	 */
1582 	for (; cons != sc->sis_tx_prod; SIS_INC(cons, SIS_TX_LIST_CNT)) {
1583 		cur_tx = &sc->sis_tx_list[cons];
1584 		txstat = le32toh(cur_tx->sis_cmdsts);
1585 		if ((txstat & SIS_CMDSTS_OWN) != 0)
1586 			break;
1587 		txd = &sc->sis_txdesc[cons];
1588 		if (txd->tx_m != NULL) {
1589 			bus_dmamap_sync(sc->sis_tx_tag, txd->tx_dmamap,
1590 			    BUS_DMASYNC_POSTWRITE);
1591 			bus_dmamap_unload(sc->sis_tx_tag, txd->tx_dmamap);
1592 			m_freem(txd->tx_m);
1593 			txd->tx_m = NULL;
1594 			if ((txstat & SIS_CMDSTS_PKT_OK) != 0) {
1595 				ifp->if_opackets++;
1596 				ifp->if_collisions +=
1597 				    (txstat & SIS_TXSTAT_COLLCNT) >> 16;
1598 			} else {
1599 				ifp->if_oerrors++;
1600 				if (txstat & SIS_TXSTAT_EXCESSCOLLS)
1601 					ifp->if_collisions++;
1602 				if (txstat & SIS_TXSTAT_OUTOFWINCOLL)
1603 					ifp->if_collisions++;
1604 			}
1605 		}
1606 		sc->sis_tx_cnt--;
1607 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
1608 	}
1609 	sc->sis_tx_cons = cons;
1610 	if (sc->sis_tx_cnt == 0)
1611 		sc->sis_watchdog_timer = 0;
1612 }
1613 
1614 static void
1615 sis_tick(void *xsc)
1616 {
1617 	struct sis_softc	*sc;
1618 	struct mii_data		*mii;
1619 	struct ifnet		*ifp;
1620 
1621 	sc = xsc;
1622 	SIS_LOCK_ASSERT(sc);
1623 	ifp = sc->sis_ifp;
1624 
1625 	mii = device_get_softc(sc->sis_miibus);
1626 	mii_tick(mii);
1627 	sis_watchdog(sc);
1628 	if ((sc->sis_flags & SIS_FLAG_LINK) == 0)
1629 		sis_miibus_statchg(sc->sis_dev);
1630 	callout_reset(&sc->sis_stat_ch, hz,  sis_tick, sc);
1631 }
1632 
1633 #ifdef DEVICE_POLLING
1634 static poll_handler_t sis_poll;
1635 
1636 static int
1637 sis_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
1638 {
1639 	struct	sis_softc *sc = ifp->if_softc;
1640 	int rx_npkts = 0;
1641 
1642 	SIS_LOCK(sc);
1643 	if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
1644 		SIS_UNLOCK(sc);
1645 		return (rx_npkts);
1646 	}
1647 
1648 	/*
1649 	 * On the sis, reading the status register also clears it.
1650 	 * So before returning to intr mode we must make sure that all
1651 	 * possible pending sources of interrupts have been served.
1652 	 * In practice this means run to completion the *eof routines,
1653 	 * and then call the interrupt routine
1654 	 */
1655 	sc->rxcycles = count;
1656 	rx_npkts = sis_rxeof(sc);
1657 	sis_txeof(sc);
1658 	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
1659 		sis_startl(ifp);
1660 
1661 	if (sc->rxcycles > 0 || cmd == POLL_AND_CHECK_STATUS) {
1662 		uint32_t	status;
1663 
1664 		/* Reading the ISR register clears all interrupts. */
1665 		status = CSR_READ_4(sc, SIS_ISR);
1666 
1667 		if (status & (SIS_ISR_RX_ERR|SIS_ISR_RX_OFLOW))
1668 			ifp->if_ierrors++;
1669 
1670 		if (status & (SIS_ISR_RX_IDLE))
1671 			SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
1672 
1673 		if (status & SIS_ISR_SYSERR) {
1674 			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1675 			sis_initl(sc);
1676 		}
1677 	}
1678 
1679 	SIS_UNLOCK(sc);
1680 	return (rx_npkts);
1681 }
1682 #endif /* DEVICE_POLLING */
1683 
1684 static void
1685 sis_intr(void *arg)
1686 {
1687 	struct sis_softc	*sc;
1688 	struct ifnet		*ifp;
1689 	uint32_t		status;
1690 
1691 	sc = arg;
1692 	ifp = sc->sis_ifp;
1693 
1694 	SIS_LOCK(sc);
1695 #ifdef DEVICE_POLLING
1696 	if (ifp->if_capenable & IFCAP_POLLING) {
1697 		SIS_UNLOCK(sc);
1698 		return;
1699 	}
1700 #endif
1701 
1702 	/* Reading the ISR register clears all interrupts. */
1703 	status = CSR_READ_4(sc, SIS_ISR);
1704 	if ((status & SIS_INTRS) == 0) {
1705 		/* Not ours. */
1706 		SIS_UNLOCK(sc);
1707 		return;
1708 	}
1709 
1710 	/* Disable interrupts. */
1711 	CSR_WRITE_4(sc, SIS_IER, 0);
1712 
1713 	for (;(status & SIS_INTRS) != 0;) {
1714 		if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
1715 			break;
1716 		if (status &
1717 		    (SIS_ISR_TX_DESC_OK | SIS_ISR_TX_ERR |
1718 		    SIS_ISR_TX_OK | SIS_ISR_TX_IDLE) )
1719 			sis_txeof(sc);
1720 
1721 		if (status & (SIS_ISR_RX_DESC_OK | SIS_ISR_RX_OK |
1722 		    SIS_ISR_RX_ERR | SIS_ISR_RX_IDLE))
1723 			sis_rxeof(sc);
1724 
1725 		if (status & SIS_ISR_RX_OFLOW)
1726 			ifp->if_ierrors++;
1727 
1728 		if (status & (SIS_ISR_RX_IDLE))
1729 			SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
1730 
1731 		if (status & SIS_ISR_SYSERR) {
1732 			ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
1733 			sis_initl(sc);
1734 			SIS_UNLOCK(sc);
1735 			return;
1736 		}
1737 		status = CSR_READ_4(sc, SIS_ISR);
1738 	}
1739 
1740 	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
1741 		/* Re-enable interrupts. */
1742 		CSR_WRITE_4(sc, SIS_IER, 1);
1743 
1744 		if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
1745 			sis_startl(ifp);
1746 	}
1747 
1748 	SIS_UNLOCK(sc);
1749 }
1750 
1751 /*
1752  * Encapsulate an mbuf chain in a descriptor by coupling the mbuf data
1753  * pointers to the fragment pointers.
1754  */
1755 static int
1756 sis_encap(struct sis_softc *sc, struct mbuf **m_head)
1757 {
1758 	struct mbuf		*m;
1759 	struct sis_txdesc	*txd;
1760 	struct sis_desc		*f;
1761 	bus_dma_segment_t	segs[SIS_MAXTXSEGS];
1762 	bus_dmamap_t		map;
1763 	int			error, i, frag, nsegs, prod;
1764 	int			padlen;
1765 
1766 	prod = sc->sis_tx_prod;
1767 	txd = &sc->sis_txdesc[prod];
1768 	if ((sc->sis_flags & SIS_FLAG_MANUAL_PAD) != 0 &&
1769 	    (*m_head)->m_pkthdr.len < SIS_MIN_FRAMELEN) {
1770 		m = *m_head;
1771 		padlen = SIS_MIN_FRAMELEN - m->m_pkthdr.len;
1772 		if (M_WRITABLE(m) == 0) {
1773 			/* Get a writable copy. */
1774 			m = m_dup(*m_head, M_DONTWAIT);
1775 			m_freem(*m_head);
1776 			if (m == NULL) {
1777 				*m_head = NULL;
1778 				return (ENOBUFS);
1779 			}
1780 			*m_head = m;
1781 		}
1782 		if (m->m_next != NULL || M_TRAILINGSPACE(m) < padlen) {
1783 			m = m_defrag(m, M_DONTWAIT);
1784 			if (m == NULL) {
1785 				m_freem(*m_head);
1786 				*m_head = NULL;
1787 				return (ENOBUFS);
1788 			}
1789 		}
1790 		/*
1791 		 * Manually pad short frames, and zero the pad space
1792 		 * to avoid leaking data.
1793 		 */
1794 		bzero(mtod(m, char *) + m->m_pkthdr.len, padlen);
1795 		m->m_pkthdr.len += padlen;
1796 		m->m_len = m->m_pkthdr.len;
1797 		*m_head = m;
1798 	}
1799 	error = bus_dmamap_load_mbuf_sg(sc->sis_tx_tag, txd->tx_dmamap,
1800 	    *m_head, segs, &nsegs, 0);
1801 	if (error == EFBIG) {
1802 		m = m_collapse(*m_head, M_DONTWAIT, SIS_MAXTXSEGS);
1803 		if (m == NULL) {
1804 			m_freem(*m_head);
1805 			*m_head = NULL;
1806 			return (ENOBUFS);
1807 		}
1808 		*m_head = m;
1809 		error = bus_dmamap_load_mbuf_sg(sc->sis_tx_tag, txd->tx_dmamap,
1810 		    *m_head, segs, &nsegs, 0);
1811 		if (error != 0) {
1812 			m_freem(*m_head);
1813 			*m_head = NULL;
1814 			return (error);
1815 		}
1816 	} else if (error != 0)
1817 		return (error);
1818 
1819 	/* Check for descriptor overruns. */
1820 	if (sc->sis_tx_cnt + nsegs > SIS_TX_LIST_CNT - 1) {
1821 		bus_dmamap_unload(sc->sis_tx_tag, txd->tx_dmamap);
1822 		return (ENOBUFS);
1823 	}
1824 
1825 	bus_dmamap_sync(sc->sis_tx_tag, txd->tx_dmamap, BUS_DMASYNC_PREWRITE);
1826 
1827 	frag = prod;
1828 	for (i = 0; i < nsegs; i++) {
1829 		f = &sc->sis_tx_list[prod];
1830 		if (i == 0)
1831 			f->sis_cmdsts = htole32(segs[i].ds_len |
1832 			    SIS_CMDSTS_MORE);
1833 		else
1834 			f->sis_cmdsts = htole32(segs[i].ds_len |
1835 			    SIS_CMDSTS_OWN | SIS_CMDSTS_MORE);
1836 		f->sis_ptr = htole32(SIS_ADDR_LO(segs[i].ds_addr));
1837 		SIS_INC(prod, SIS_TX_LIST_CNT);
1838 		sc->sis_tx_cnt++;
1839 	}
1840 
1841 	/* Update producer index. */
1842 	sc->sis_tx_prod = prod;
1843 
1844 	/* Remove MORE flag on the last descriptor. */
1845 	prod = (prod - 1) & (SIS_TX_LIST_CNT - 1);
1846 	f = &sc->sis_tx_list[prod];
1847 	f->sis_cmdsts &= ~htole32(SIS_CMDSTS_MORE);
1848 
1849 	/* Lastly transfer ownership of packet to the controller. */
1850 	f = &sc->sis_tx_list[frag];
1851 	f->sis_cmdsts |= htole32(SIS_CMDSTS_OWN);
1852 
1853 	/* Swap the last and the first dmamaps. */
1854 	map = txd->tx_dmamap;
1855 	txd->tx_dmamap = sc->sis_txdesc[prod].tx_dmamap;
1856 	sc->sis_txdesc[prod].tx_dmamap = map;
1857 	sc->sis_txdesc[prod].tx_m = *m_head;
1858 
1859 	return (0);
1860 }
1861 
1862 static void
1863 sis_start(struct ifnet *ifp)
1864 {
1865 	struct sis_softc	*sc;
1866 
1867 	sc = ifp->if_softc;
1868 	SIS_LOCK(sc);
1869 	sis_startl(ifp);
1870 	SIS_UNLOCK(sc);
1871 }
1872 
1873 static void
1874 sis_startl(struct ifnet *ifp)
1875 {
1876 	struct sis_softc	*sc;
1877 	struct mbuf		*m_head;
1878 	int			queued;
1879 
1880 	sc = ifp->if_softc;
1881 
1882 	SIS_LOCK_ASSERT(sc);
1883 
1884 	if ((ifp->if_drv_flags & (IFF_DRV_RUNNING | IFF_DRV_OACTIVE)) !=
1885 	    IFF_DRV_RUNNING || (sc->sis_flags & SIS_FLAG_LINK) == 0)
1886 		return;
1887 
1888 	for (queued = 0; !IFQ_DRV_IS_EMPTY(&ifp->if_snd) &&
1889 	    sc->sis_tx_cnt < SIS_TX_LIST_CNT - 4;) {
1890 		IFQ_DRV_DEQUEUE(&ifp->if_snd, m_head);
1891 		if (m_head == NULL)
1892 			break;
1893 
1894 		if (sis_encap(sc, &m_head) != 0) {
1895 			if (m_head == NULL)
1896 				break;
1897 			IFQ_DRV_PREPEND(&ifp->if_snd, m_head);
1898 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
1899 			break;
1900 		}
1901 
1902 		queued++;
1903 
1904 		/*
1905 		 * If there's a BPF listener, bounce a copy of this frame
1906 		 * to him.
1907 		 */
1908 		BPF_MTAP(ifp, m_head);
1909 	}
1910 
1911 	if (queued) {
1912 		/* Transmit */
1913 		bus_dmamap_sync(sc->sis_tx_list_tag, sc->sis_tx_list_map,
1914 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1915 		SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_ENABLE);
1916 
1917 		/*
1918 		 * Set a timeout in case the chip goes out to lunch.
1919 		 */
1920 		sc->sis_watchdog_timer = 5;
1921 	}
1922 }
1923 
1924 static void
1925 sis_init(void *xsc)
1926 {
1927 	struct sis_softc	*sc = xsc;
1928 
1929 	SIS_LOCK(sc);
1930 	sis_initl(sc);
1931 	SIS_UNLOCK(sc);
1932 }
1933 
1934 static void
1935 sis_initl(struct sis_softc *sc)
1936 {
1937 	struct ifnet		*ifp = sc->sis_ifp;
1938 	struct mii_data		*mii;
1939 	uint8_t			*eaddr;
1940 
1941 	SIS_LOCK_ASSERT(sc);
1942 
1943 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
1944 		return;
1945 
1946 	/*
1947 	 * Cancel pending I/O and free all RX/TX buffers.
1948 	 */
1949 	sis_stop(sc);
1950 	/*
1951 	 * Reset the chip to a known state.
1952 	 */
1953 	sis_reset(sc);
1954 #ifdef notyet
1955 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr >= NS_SRR_16A) {
1956 		/*
1957 		 * Configure 400usec of interrupt holdoff.  This is based
1958 		 * on emperical tests on a Soekris 4801.
1959  		 */
1960 		CSR_WRITE_4(sc, NS_IHR, 0x100 | 4);
1961 	}
1962 #endif
1963 
1964 	mii = device_get_softc(sc->sis_miibus);
1965 
1966 	/* Set MAC address */
1967 	eaddr = IF_LLADDR(sc->sis_ifp);
1968 	if (sc->sis_type == SIS_TYPE_83815) {
1969 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_PAR0);
1970 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[0] | eaddr[1] << 8);
1971 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_PAR1);
1972 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[2] | eaddr[3] << 8);
1973 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, NS_FILTADDR_PAR2);
1974 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[4] | eaddr[5] << 8);
1975 	} else {
1976 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR0);
1977 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[0] | eaddr[1] << 8);
1978 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR1);
1979 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[2] | eaddr[3] << 8);
1980 		CSR_WRITE_4(sc, SIS_RXFILT_CTL, SIS_FILTADDR_PAR2);
1981 		CSR_WRITE_4(sc, SIS_RXFILT_DATA, eaddr[4] | eaddr[5] << 8);
1982 	}
1983 
1984 	/* Init circular TX/RX lists. */
1985 	if (sis_ring_init(sc) != 0) {
1986 		device_printf(sc->sis_dev,
1987 		    "initialization failed: no memory for rx buffers\n");
1988 		sis_stop(sc);
1989 		return;
1990 	}
1991 
1992 	if (sc->sis_type == SIS_TYPE_83815 || sc->sis_type == SIS_TYPE_83816) {
1993 		if (sc->sis_manual_pad != 0)
1994 			sc->sis_flags |= SIS_FLAG_MANUAL_PAD;
1995 		else
1996 			sc->sis_flags &= ~SIS_FLAG_MANUAL_PAD;
1997 	}
1998 
1999 	/*
2000 	 * Short Cable Receive Errors (MP21.E)
2001 	 * also: Page 78 of the DP83815 data sheet (september 2002 version)
2002 	 * recommends the following register settings "for optimum
2003 	 * performance." for rev 15C.  Set this also for 15D parts as
2004 	 * they require it in practice.
2005 	 */
2006 	if (sc->sis_type == SIS_TYPE_83815 && sc->sis_srr <= NS_SRR_15D) {
2007 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0x0001);
2008 		CSR_WRITE_4(sc, NS_PHY_CR, 0x189C);
2009 		/* set val for c2 */
2010 		CSR_WRITE_4(sc, NS_PHY_TDATA, 0x0000);
2011 		/* load/kill c2 */
2012 		CSR_WRITE_4(sc, NS_PHY_DSPCFG, 0x5040);
2013 		/* rais SD off, from 4 to c */
2014 		CSR_WRITE_4(sc, NS_PHY_SDCFG, 0x008C);
2015 		CSR_WRITE_4(sc, NS_PHY_PAGE, 0);
2016 	}
2017 
2018 	sis_rxfilter(sc);
2019 	/* Turn the receive filter on */
2020 	SIS_SETBIT(sc, SIS_RXFILT_CTL, SIS_RXFILTCTL_ENABLE);
2021 
2022 	/*
2023 	 * Load the address of the RX and TX lists.
2024 	 */
2025 	CSR_WRITE_4(sc, SIS_RX_LISTPTR, SIS_ADDR_LO(sc->sis_rx_paddr));
2026 	CSR_WRITE_4(sc, SIS_TX_LISTPTR, SIS_ADDR_LO(sc->sis_tx_paddr));
2027 
2028 	/* SIS_CFG_EDB_MASTER_EN indicates the EDB bus is used instead of
2029 	 * the PCI bus. When this bit is set, the Max DMA Burst Size
2030 	 * for TX/RX DMA should be no larger than 16 double words.
2031 	 */
2032 	if (CSR_READ_4(sc, SIS_CFG) & SIS_CFG_EDB_MASTER_EN) {
2033 		CSR_WRITE_4(sc, SIS_RX_CFG, SIS_RXCFG64);
2034 	} else {
2035 		CSR_WRITE_4(sc, SIS_RX_CFG, SIS_RXCFG256);
2036 	}
2037 
2038 	/* Accept Long Packets for VLAN support */
2039 	SIS_SETBIT(sc, SIS_RX_CFG, SIS_RXCFG_RX_JABBER);
2040 
2041 	/*
2042 	 * Assume 100Mbps link, actual MAC configuration is done
2043 	 * after getting a valid link.
2044 	 */
2045 	CSR_WRITE_4(sc, SIS_TX_CFG, SIS_TXCFG_100);
2046 
2047 	/*
2048 	 * Enable interrupts.
2049 	 */
2050 	CSR_WRITE_4(sc, SIS_IMR, SIS_INTRS);
2051 #ifdef DEVICE_POLLING
2052 	/*
2053 	 * ... only enable interrupts if we are not polling, make sure
2054 	 * they are off otherwise.
2055 	 */
2056 	if (ifp->if_capenable & IFCAP_POLLING)
2057 		CSR_WRITE_4(sc, SIS_IER, 0);
2058 	else
2059 #endif
2060 	CSR_WRITE_4(sc, SIS_IER, 1);
2061 
2062 	/* Clear MAC disable. */
2063 	SIS_CLRBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE | SIS_CSR_RX_DISABLE);
2064 
2065 	sc->sis_flags &= ~SIS_FLAG_LINK;
2066 	mii_mediachg(mii);
2067 
2068 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
2069 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
2070 
2071 	callout_reset(&sc->sis_stat_ch, hz,  sis_tick, sc);
2072 }
2073 
2074 /*
2075  * Set media options.
2076  */
2077 static int
2078 sis_ifmedia_upd(struct ifnet *ifp)
2079 {
2080 	struct sis_softc	*sc;
2081 	struct mii_data		*mii;
2082 	struct mii_softc	*miisc;
2083 	int			error;
2084 
2085 	sc = ifp->if_softc;
2086 
2087 	SIS_LOCK(sc);
2088 	mii = device_get_softc(sc->sis_miibus);
2089 	LIST_FOREACH(miisc, &mii->mii_phys, mii_list)
2090 		PHY_RESET(miisc);
2091 	error = mii_mediachg(mii);
2092 	SIS_UNLOCK(sc);
2093 
2094 	return (error);
2095 }
2096 
2097 /*
2098  * Report current media status.
2099  */
2100 static void
2101 sis_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
2102 {
2103 	struct sis_softc	*sc;
2104 	struct mii_data		*mii;
2105 
2106 	sc = ifp->if_softc;
2107 
2108 	SIS_LOCK(sc);
2109 	mii = device_get_softc(sc->sis_miibus);
2110 	mii_pollstat(mii);
2111 	ifmr->ifm_active = mii->mii_media_active;
2112 	ifmr->ifm_status = mii->mii_media_status;
2113 	SIS_UNLOCK(sc);
2114 }
2115 
2116 static int
2117 sis_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
2118 {
2119 	struct sis_softc	*sc = ifp->if_softc;
2120 	struct ifreq		*ifr = (struct ifreq *) data;
2121 	struct mii_data		*mii;
2122 	int			error = 0, mask;
2123 
2124 	switch (command) {
2125 	case SIOCSIFFLAGS:
2126 		SIS_LOCK(sc);
2127 		if (ifp->if_flags & IFF_UP) {
2128 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0 &&
2129 			    ((ifp->if_flags ^ sc->sis_if_flags) &
2130 			    (IFF_PROMISC | IFF_ALLMULTI)) != 0)
2131 				sis_rxfilter(sc);
2132 			else
2133 				sis_initl(sc);
2134 		} else if (ifp->if_drv_flags & IFF_DRV_RUNNING)
2135 			sis_stop(sc);
2136 		sc->sis_if_flags = ifp->if_flags;
2137 		SIS_UNLOCK(sc);
2138 		break;
2139 	case SIOCADDMULTI:
2140 	case SIOCDELMULTI:
2141 		SIS_LOCK(sc);
2142 		sis_rxfilter(sc);
2143 		SIS_UNLOCK(sc);
2144 		break;
2145 	case SIOCGIFMEDIA:
2146 	case SIOCSIFMEDIA:
2147 		mii = device_get_softc(sc->sis_miibus);
2148 		error = ifmedia_ioctl(ifp, ifr, &mii->mii_media, command);
2149 		break;
2150 	case SIOCSIFCAP:
2151 		SIS_LOCK(sc);
2152 		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
2153 #ifdef DEVICE_POLLING
2154 		if ((mask & IFCAP_POLLING) != 0 &&
2155 		    (IFCAP_POLLING & ifp->if_capabilities) != 0) {
2156 			ifp->if_capenable ^= IFCAP_POLLING;
2157 			if ((IFCAP_POLLING & ifp->if_capenable) != 0) {
2158 				error = ether_poll_register(sis_poll, ifp);
2159 				if (error != 0) {
2160 					SIS_UNLOCK(sc);
2161 					break;
2162 				}
2163 				/* Disable interrupts. */
2164 				CSR_WRITE_4(sc, SIS_IER, 0);
2165                         } else {
2166                                 error = ether_poll_deregister(ifp);
2167                                 /* Enable interrupts. */
2168 				CSR_WRITE_4(sc, SIS_IER, 1);
2169                         }
2170 		}
2171 #endif /* DEVICE_POLLING */
2172 		if ((mask & IFCAP_WOL) != 0 &&
2173 		    (ifp->if_capabilities & IFCAP_WOL) != 0) {
2174 			if ((mask & IFCAP_WOL_UCAST) != 0)
2175 				ifp->if_capenable ^= IFCAP_WOL_UCAST;
2176 			if ((mask & IFCAP_WOL_MCAST) != 0)
2177 				ifp->if_capenable ^= IFCAP_WOL_MCAST;
2178 			if ((mask & IFCAP_WOL_MAGIC) != 0)
2179 				ifp->if_capenable ^= IFCAP_WOL_MAGIC;
2180 		}
2181 		SIS_UNLOCK(sc);
2182 		break;
2183 	default:
2184 		error = ether_ioctl(ifp, command, data);
2185 		break;
2186 	}
2187 
2188 	return (error);
2189 }
2190 
2191 static void
2192 sis_watchdog(struct sis_softc *sc)
2193 {
2194 
2195 	SIS_LOCK_ASSERT(sc);
2196 
2197 	if (sc->sis_watchdog_timer == 0 || --sc->sis_watchdog_timer >0)
2198 		return;
2199 
2200 	device_printf(sc->sis_dev, "watchdog timeout\n");
2201 	sc->sis_ifp->if_oerrors++;
2202 
2203 	sc->sis_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
2204 	sis_initl(sc);
2205 
2206 	if (!IFQ_DRV_IS_EMPTY(&sc->sis_ifp->if_snd))
2207 		sis_startl(sc->sis_ifp);
2208 }
2209 
2210 /*
2211  * Stop the adapter and free any mbufs allocated to the
2212  * RX and TX lists.
2213  */
2214 static void
2215 sis_stop(struct sis_softc *sc)
2216 {
2217 	struct ifnet *ifp;
2218 	struct sis_rxdesc *rxd;
2219 	struct sis_txdesc *txd;
2220 	int i;
2221 
2222 	SIS_LOCK_ASSERT(sc);
2223 
2224 	ifp = sc->sis_ifp;
2225 	sc->sis_watchdog_timer = 0;
2226 
2227 	callout_stop(&sc->sis_stat_ch);
2228 
2229 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
2230 	CSR_WRITE_4(sc, SIS_IER, 0);
2231 	CSR_WRITE_4(sc, SIS_IMR, 0);
2232 	CSR_READ_4(sc, SIS_ISR); /* clear any interrupts already pending */
2233 	SIS_SETBIT(sc, SIS_CSR, SIS_CSR_TX_DISABLE|SIS_CSR_RX_DISABLE);
2234 	DELAY(1000);
2235 	CSR_WRITE_4(sc, SIS_TX_LISTPTR, 0);
2236 	CSR_WRITE_4(sc, SIS_RX_LISTPTR, 0);
2237 
2238 	sc->sis_flags &= ~SIS_FLAG_LINK;
2239 
2240 	/*
2241 	 * Free data in the RX lists.
2242 	 */
2243 	for (i = 0; i < SIS_RX_LIST_CNT; i++) {
2244 		rxd = &sc->sis_rxdesc[i];
2245 		if (rxd->rx_m != NULL) {
2246 			bus_dmamap_sync(sc->sis_rx_tag, rxd->rx_dmamap,
2247 			    BUS_DMASYNC_POSTREAD);
2248 			bus_dmamap_unload(sc->sis_rx_tag, rxd->rx_dmamap);
2249 			m_freem(rxd->rx_m);
2250 			rxd->rx_m = NULL;
2251 		}
2252 	}
2253 
2254 	/*
2255 	 * Free the TX list buffers.
2256 	 */
2257 	for (i = 0; i < SIS_TX_LIST_CNT; i++) {
2258 		txd = &sc->sis_txdesc[i];
2259 		if (txd->tx_m != NULL) {
2260 			bus_dmamap_sync(sc->sis_tx_tag, txd->tx_dmamap,
2261 			    BUS_DMASYNC_POSTWRITE);
2262 			bus_dmamap_unload(sc->sis_tx_tag, txd->tx_dmamap);
2263 			m_freem(txd->tx_m);
2264 			txd->tx_m = NULL;
2265 		}
2266 	}
2267 }
2268 
2269 /*
2270  * Stop all chip I/O so that the kernel's probe routines don't
2271  * get confused by errant DMAs when rebooting.
2272  */
2273 static int
2274 sis_shutdown(device_t dev)
2275 {
2276 
2277 	return (sis_suspend(dev));
2278 }
2279 
2280 static int
2281 sis_suspend(device_t dev)
2282 {
2283 	struct sis_softc	*sc;
2284 
2285 	sc = device_get_softc(dev);
2286 	SIS_LOCK(sc);
2287 	sis_stop(sc);
2288 	sis_wol(sc);
2289 	SIS_UNLOCK(sc);
2290 	return (0);
2291 }
2292 
2293 static int
2294 sis_resume(device_t dev)
2295 {
2296 	struct sis_softc	*sc;
2297 	struct ifnet		*ifp;
2298 
2299 	sc = device_get_softc(dev);
2300 	SIS_LOCK(sc);
2301 	ifp = sc->sis_ifp;
2302 	if ((ifp->if_flags & IFF_UP) != 0) {
2303 		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
2304 		sis_initl(sc);
2305 	}
2306 	SIS_UNLOCK(sc);
2307 	return (0);
2308 }
2309 
2310 static void
2311 sis_wol(struct sis_softc *sc)
2312 {
2313 	struct ifnet		*ifp;
2314 	uint32_t		val;
2315 	uint16_t		pmstat;
2316 	int			pmc;
2317 
2318 	ifp = sc->sis_ifp;
2319 	if ((ifp->if_capenable & IFCAP_WOL) == 0)
2320 		return;
2321 
2322 	if (sc->sis_type == SIS_TYPE_83815) {
2323 		/* Reset RXDP. */
2324 		CSR_WRITE_4(sc, SIS_RX_LISTPTR, 0);
2325 
2326 		/* Configure WOL events. */
2327 		CSR_READ_4(sc, NS_WCSR);
2328 		val = 0;
2329 		if ((ifp->if_capenable & IFCAP_WOL_UCAST) != 0)
2330 			val |= NS_WCSR_WAKE_UCAST;
2331 		if ((ifp->if_capenable & IFCAP_WOL_MCAST) != 0)
2332 			val |= NS_WCSR_WAKE_MCAST;
2333 		if ((ifp->if_capenable & IFCAP_WOL_MAGIC) != 0)
2334 			val |= NS_WCSR_WAKE_MAGIC;
2335 		CSR_WRITE_4(sc, NS_WCSR, val);
2336 		/* Enable PME and clear PMESTS. */
2337 		val = CSR_READ_4(sc, NS_CLKRUN);
2338 		val |= NS_CLKRUN_PMEENB | NS_CLKRUN_PMESTS;
2339 		CSR_WRITE_4(sc, NS_CLKRUN, val);
2340 		/* Enable silent RX mode. */
2341 		SIS_SETBIT(sc, SIS_CSR, SIS_CSR_RX_ENABLE);
2342 	} else {
2343 		if (pci_find_cap(sc->sis_dev, PCIY_PMG, &pmc) != 0)
2344 			return;
2345 		val = 0;
2346 		if ((ifp->if_capenable & IFCAP_WOL_MAGIC) != 0)
2347 			val |= SIS_PWRMAN_WOL_MAGIC;
2348 		CSR_WRITE_4(sc, SIS_PWRMAN_CTL, val);
2349 		/* Request PME. */
2350 		pmstat = pci_read_config(sc->sis_dev,
2351 		    pmc + PCIR_POWER_STATUS, 2);
2352 		pmstat &= ~(PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE);
2353 		if ((ifp->if_capenable & IFCAP_WOL_MAGIC) != 0)
2354 			pmstat |= PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE;
2355 		pci_write_config(sc->sis_dev,
2356 		    pmc + PCIR_POWER_STATUS, pmstat, 2);
2357 	}
2358 }
2359 
2360 static void
2361 sis_add_sysctls(struct sis_softc *sc)
2362 {
2363 	struct sysctl_ctx_list *ctx;
2364 	struct sysctl_oid_list *children;
2365 	char tn[32];
2366 	int unit;
2367 
2368 	ctx = device_get_sysctl_ctx(sc->sis_dev);
2369 	children = SYSCTL_CHILDREN(device_get_sysctl_tree(sc->sis_dev));
2370 
2371 	unit = device_get_unit(sc->sis_dev);
2372 	/*
2373 	 * Unlike most other controllers, NS DP83815/DP83816 controllers
2374 	 * seem to pad with 0xFF when it encounter short frames.  According
2375 	 * to RFC 1042 the pad bytes should be 0x00.  Turning this tunable
2376 	 * on will have driver pad manully but it's disabled by default
2377 	 * because it will consume extra CPU cycles for short frames.
2378 	 */
2379 	sc->sis_manual_pad = 0;
2380 	snprintf(tn, sizeof(tn), "dev.sis.%d.manual_pad", unit);
2381 	TUNABLE_INT_FETCH(tn, &sc->sis_manual_pad);
2382 	SYSCTL_ADD_INT(ctx, children, OID_AUTO, "manual_pad",
2383 	    CTLFLAG_RW, &sc->sis_manual_pad, 0, "Manually pad short frames");
2384 }
2385 
2386 static device_method_t sis_methods[] = {
2387 	/* Device interface */
2388 	DEVMETHOD(device_probe,		sis_probe),
2389 	DEVMETHOD(device_attach,	sis_attach),
2390 	DEVMETHOD(device_detach,	sis_detach),
2391 	DEVMETHOD(device_shutdown,	sis_shutdown),
2392 	DEVMETHOD(device_suspend,	sis_suspend),
2393 	DEVMETHOD(device_resume,	sis_resume),
2394 
2395 	/* MII interface */
2396 	DEVMETHOD(miibus_readreg,	sis_miibus_readreg),
2397 	DEVMETHOD(miibus_writereg,	sis_miibus_writereg),
2398 	DEVMETHOD(miibus_statchg,	sis_miibus_statchg),
2399 
2400 	DEVMETHOD_END
2401 };
2402 
2403 static driver_t sis_driver = {
2404 	"sis",
2405 	sis_methods,
2406 	sizeof(struct sis_softc)
2407 };
2408 
2409 static devclass_t sis_devclass;
2410 
2411 DRIVER_MODULE(sis, pci, sis_driver, sis_devclass, 0, 0);
2412 DRIVER_MODULE(miibus, sis, miibus_driver, miibus_devclass, 0, 0);
2413