xref: /dragonfly/sys/dev/netif/sbsh/if_sbsh.c (revision 32efd857)
1 /**
2  * Granch SBNI16 G.SHDSL Modem driver
3  * Written by Denis I. Timofeev, 2002-2003.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD: src/sys/dev/sbsh/if_sbsh.c,v 1.3.2.1 2003/04/15 18:15:07 fjoe Exp $
27  */
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/sockio.h>
32 #include <sys/mbuf.h>
33 #include <sys/malloc.h>
34 #include <sys/kernel.h>
35 #include <sys/proc.h>
36 #include <sys/priv.h>
37 #include <sys/socket.h>
38 #include <sys/random.h>
39 #include <sys/serialize.h>
40 #include <sys/bus.h>
41 #include <sys/rman.h>
42 #include <sys/interrupt.h>
43 
44 #include <net/if.h>
45 #include <net/ifq_var.h>
46 #include <net/if_arp.h>
47 #include <net/ethernet.h>
48 #include <net/if_media.h>
49 
50 #include <net/bpf.h>
51 
52 #include <vm/vm.h>
53 #include <vm/pmap.h>
54 
55 #include <bus/pci/pcireg.h>
56 #include <bus/pci/pcivar.h>
57 
58 #include "if_sbshreg.h"
59 
60 /* -------------------------------------------------------------------------- */
61 
62 struct sbni16_hw_regs {
63 	u_int8_t  CR, CRB, SR, IMR, CTDR, LTDR, CRDR, LRDR;
64 };
65 
66 struct hw_descr {
67 	u_int32_t  address;
68 	u_int32_t  length;
69 };
70 
71 struct cx28975_cmdarea {
72 	u_int8_t  intr_host;
73 	u_int8_t  intr_8051;
74 	u_int8_t  map_version;
75 
76 	u_int8_t  in_dest;
77 	u_int8_t  in_opcode;
78 	u_int8_t  in_zero;
79 	u_int8_t  in_length;
80 	u_int8_t  in_csum;
81 	u_int8_t  in_data[75];
82 	u_int8_t  in_datasum;
83 
84 	u_int8_t  out_dest;
85 	u_int8_t  out_opcode;
86 	u_int8_t  out_ack;
87 	u_int8_t  out_length;
88 	u_int8_t  out_csum;
89 	u_int8_t  out_data[75];
90 	u_int8_t  out_datasum;
91 };
92 
93 #define XQLEN	8
94 #define RQLEN	8
95 
96 struct sbsh_softc {
97 	struct arpcom	arpcom;		/* ethernet common */
98 
99 	struct resource	*mem_res;
100 	struct resource	*irq_res;
101 	void		*intr_hand;
102 
103 	void		*mem_base;		/* mapped memory address */
104 
105 	volatile struct sbni16_hw_regs	*regs;
106 	volatile struct hw_descr	*tbd;
107 	volatile struct hw_descr	*rbd;
108 	volatile struct cx28975_cmdarea	*cmdp;
109 
110 	/* SBNI16 controller statistics */
111 	struct sbni16_stats {
112 		u_int32_t  sent_pkts, rcvd_pkts;
113 		u_int32_t  crc_errs, ufl_errs, ofl_errs, attempts, last_time;
114 	} in_stats;
115 
116 	/* transmit and reception queues */
117 	struct mbuf	*xq[XQLEN], *rq[RQLEN];
118 	unsigned	head_xq, tail_xq, head_rq, tail_rq;
119 
120 	/* the descriptors mapped onto the first buffers in xq and rq */
121 	unsigned	head_tdesc, head_rdesc;
122 	u_int8_t	state;
123 };
124 
125 struct cx28975_cfg {
126 	u_int8_t   *firmw_image;
127 	u_int32_t  firmw_len;
128 	u_int32_t  lrate: 10;
129 	u_int32_t  master: 1;
130 	u_int32_t  mod: 2;
131 	u_int32_t  crc16: 1;
132 	u_int32_t  fill_7e: 1;
133 	u_int32_t  inv: 1;
134 	u_int32_t  rburst: 1;
135 	u_int32_t  wburst: 1;
136 	u_int32_t  : 14;
137 };
138 
139 /* SHDSL transceiver statistics */
140 struct dsl_stats {
141 	u_int8_t	status_1, status_3;
142 	u_int8_t	attenuat, nmr, tpbo, rpbo;
143 	u_int16_t	losw, segd, crc, sega, losd;
144 };
145 
146 enum State { NOT_LOADED, DOWN, ACTIVATION, ACTIVE };
147 
148 #define	SIOCLOADFIRMW	_IOWR('i', 67, struct ifreq)
149 #define SIOCGETSTATS	_IOWR('i', 68, struct ifreq)
150 #define SIOCCLRSTATS	_IOWR('i', 69, struct ifreq)
151 
152 static int	sbsh_probe(device_t);
153 static int	sbsh_attach(device_t);
154 static int	sbsh_detach(device_t);
155 static int	sbsh_ioctl(struct ifnet	*, u_long, caddr_t, struct ucred *);
156 static void	sbsh_shutdown(device_t);
157 static int	sbsh_suspend(device_t);
158 static int	sbsh_resume(device_t);
159 static void	sbsh_watchdog(struct ifnet *);
160 
161 static void	sbsh_start(struct ifnet *, struct ifaltq_subque *);
162 static void	sbsh_init(void *);
163 static void	sbsh_stop(struct sbsh_softc *);
164 static void	init_card(struct sbsh_softc *);
165 static void	sbsh_intr(void *);
166 static void	resume_tx(struct sbsh_softc *);
167 static void	start_xmit_frames(struct sbsh_softc *);
168 static void	encap_frame(struct sbsh_softc *, struct mbuf *);
169 static struct mbuf *	repack(struct sbsh_softc *, struct mbuf *);
170 static void	free_sent_buffers(struct sbsh_softc *);
171 static void	alloc_rx_buffers(struct sbsh_softc *);
172 static void	indicate_frames(struct sbsh_softc *);
173 static void	drop_queues(struct sbsh_softc *);
174 static void	activate(struct sbsh_softc *);
175 static void	deactivate(struct sbsh_softc *);
176 static void	cx28975_interrupt(struct sbsh_softc *);
177 static int	start_cx28975(struct sbsh_softc *, struct cx28975_cfg);
178 static int	download_firmware(struct sbsh_softc *, u_int8_t *, u_int32_t);
179 static int	issue_cx28975_cmd(struct sbsh_softc *, u_int8_t,
180 					u_int8_t *, u_int8_t);
181 
182 static device_method_t sbsh_methods[] = {
183 	/* Device interface */
184 	DEVMETHOD(device_probe,		sbsh_probe),
185 	DEVMETHOD(device_attach,	sbsh_attach),
186 	DEVMETHOD(device_detach,	sbsh_detach),
187 	DEVMETHOD(device_shutdown,	sbsh_shutdown),
188 	DEVMETHOD(device_suspend,	sbsh_suspend),
189 	DEVMETHOD(device_resume,	sbsh_resume),
190 
191 	DEVMETHOD_END
192 };
193 
194 static driver_t sbsh_driver = {
195 	"sbsh",
196 	sbsh_methods,
197 	sizeof(struct sbsh_softc)
198 };
199 
200 static devclass_t sbsh_devclass;
201 
202 DECLARE_DUMMY_MODULE(if_sbsh);
203 DRIVER_MODULE(if_sbsh, pci, sbsh_driver, sbsh_devclass, NULL, NULL);
204 
205 static int
206 sbsh_probe(device_t dev)
207 {
208 	if (pci_get_vendor(dev) != SBNI16_VENDOR
209 	    || pci_get_device(dev) != SBNI16_DEVICE
210 	    || pci_get_subdevice(dev) != SBNI16_SUBDEV)
211 		return (ENXIO);
212 
213 	device_set_desc(dev, "Granch SBNI16 G.SHDSL Modem");
214 	return (0);
215 }
216 
217 static int
218 sbsh_attach(device_t dev)
219 {
220 	struct sbsh_softc	*sc;
221 	struct ifnet		*ifp;
222 	int			unit, error = 0, rid;
223 
224 	sc = device_get_softc(dev);
225 	unit = device_get_unit(dev);
226 
227 	rid = PCIR_MAPS + 4;
228 	sc->mem_res = bus_alloc_resource(dev, SYS_RES_MEMORY, &rid,
229 					0, ~0, 4096, RF_ACTIVE);
230 
231 	if (sc->mem_res == NULL) {
232 		kprintf ("sbsh%d: couldn't map memory\n", unit);
233 		error = ENXIO;
234 		goto fail;
235 	}
236 
237 	rid = 0;
238 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
239 	    RF_SHAREABLE | RF_ACTIVE);
240 
241 	if (sc->irq_res == NULL) {
242 		kprintf("sbsh%d: couldn't map interrupt\n", unit);
243 		error = ENXIO;
244 		goto fail;
245 	}
246 
247 	sc->mem_base = rman_get_virtual(sc->mem_res);
248 	init_card(sc);
249 	/* generate ethernet MAC address */
250 	*(u_int32_t *)sc->arpcom.ac_enaddr = htonl(0x00ff0192);
251 	read_random(sc->arpcom.ac_enaddr + 4, 2, 1);
252 
253 	ifp = &sc->arpcom.ac_if;
254 	ifp->if_softc = sc;
255 	if_initname(ifp, "sbsh", unit);
256 	ifp->if_mtu = ETHERMTU;
257 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
258 	ifp->if_ioctl = sbsh_ioctl;
259 	ifp->if_start = sbsh_start;
260 	ifp->if_watchdog = sbsh_watchdog;
261 	ifp->if_init = sbsh_init;
262 	ifp->if_baudrate = 4600000;
263 	ifq_set_maxlen(&ifp->if_snd, IFQ_MAXLEN);
264 	ifq_set_ready(&ifp->if_snd);
265 
266 	ether_ifattach(ifp, sc->arpcom.ac_enaddr, NULL);
267 
268 	ifq_set_cpuid(&ifp->if_snd, rman_get_cpuid(sc->irq_res));
269 
270 	error = bus_setup_intr(dev, sc->irq_res, INTR_MPSAFE,
271 				sbsh_intr, sc, &sc->intr_hand,
272 				ifp->if_serializer);
273 	if (error) {
274 		ether_ifdetach(ifp);
275 		kprintf("sbsh%d: couldn't set up irq\n", unit);
276 		goto fail;
277 	}
278 
279 	return(0);
280 
281 fail:
282 	sbsh_detach(dev);
283 	return (error);
284 }
285 
286 static int
287 sbsh_detach(device_t dev)
288 {
289 	struct sbsh_softc *sc = device_get_softc(dev);
290 	struct ifnet *ifp = &sc->arpcom.ac_if;
291 
292 	if (device_is_attached(dev)) {
293 		lwkt_serialize_enter(ifp->if_serializer);
294 		sbsh_stop(sc);
295 		bus_teardown_intr(dev, sc->irq_res, sc->intr_hand);
296 		lwkt_serialize_exit(ifp->if_serializer);
297 
298 		ether_ifdetach(ifp);
299 	}
300 
301 	if (sc->irq_res)
302 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->irq_res);
303 	if (sc->mem_res) {
304 		bus_release_resource(dev, SYS_RES_MEMORY, PCIR_MAPS + 4,
305 				     sc->mem_res);
306 	}
307 
308 	return (0);
309 }
310 
311 
312 static void
313 sbsh_start(struct ifnet *ifp, struct ifaltq_subque *ifsq)
314 {
315 	struct sbsh_softc  *sc = ifp->if_softc;
316 
317 	ASSERT_ALTQ_SQ_DEFAULT(ifp, ifsq);
318 
319 	if (sc->state == ACTIVE)
320 		start_xmit_frames(ifp->if_softc);
321 }
322 
323 
324 static void
325 sbsh_init(void *xsc)
326 {
327 	struct sbsh_softc	*sc = xsc;
328 	struct ifnet		*ifp = &sc->arpcom.ac_if;
329 	u_int8_t		t;
330 
331 	if ((ifp->if_flags & IFF_RUNNING) || sc->state == NOT_LOADED) {
332 		return;
333 	}
334 
335 	bzero(&sc->in_stats, sizeof(struct sbni16_stats));
336 	sc->head_xq = sc->tail_xq = sc->head_rq = sc->tail_rq = 0;
337 	sc->head_tdesc = sc->head_rdesc = 0;
338 
339 	sc->regs->IMR = EXT;
340 	t = 2;
341 	issue_cx28975_cmd(sc, _DSL_CLEAR_ERROR_CTRS, &t, 1);
342 	if (issue_cx28975_cmd(sc, _DSL_ACTIVATION, &t, 1) == 0) {
343 		sc->state = ACTIVATION;
344 
345 		ifp->if_flags |= IFF_RUNNING;
346 		ifq_clr_oactive(&ifp->if_snd);
347 	}
348 }
349 
350 
351 static void
352 sbsh_stop(struct sbsh_softc *sc)
353 {
354 	u_int8_t  t;
355 
356 	sc->regs->IMR = EXT;
357 
358 	t = 0;
359 	issue_cx28975_cmd(sc, _DSL_ACTIVATION, &t, 1);
360 	if (sc->state == ACTIVE) {
361 		t = 1;
362 		issue_cx28975_cmd(sc, _DSL_FORCE_DEACTIVATE, &t, 1);
363 		/* FIX! activation manager state */
364 
365 		/* Is it really must be done here? It calls from intr handler */
366 		deactivate(sc);
367 	}
368 
369 	sc->regs->IMR = 0;
370 	sc->state = DOWN;
371 }
372 
373 
374 static void
375 init_card(struct sbsh_softc *sc)
376 {
377 	sc->state = NOT_LOADED;
378 	sc->tbd  = (struct hw_descr *) sc->mem_base;
379 	sc->rbd  = (struct hw_descr *) ((u_int8_t *)sc->mem_base + 0x400);
380 	sc->regs = (struct sbni16_hw_regs *) ((u_int8_t *)sc->mem_base + 0x800);
381 	sc->cmdp = (struct cx28975_cmdarea *) ((u_int8_t *)sc->mem_base + 0xc00);
382 
383 	sc->regs->CR = 0;
384 	sc->regs->SR = 0xff;
385 	sc->regs->IMR = 0;
386 }
387 
388 
389 static int
390 sbsh_ioctl(struct ifnet	*ifp, u_long cmd, caddr_t data, struct ucred *cr)
391 {
392 	struct sbsh_softc	*sc = ifp->if_softc;
393 	struct ifreq		*ifr = (struct ifreq *) data;
394 	struct cx28975_cfg	cfg;
395 	struct dsl_stats	ds;
396 	int			error = 0;
397 	u_int8_t		t;
398 
399 	switch(cmd) {
400 	case SIOCLOADFIRMW:
401 		if ((error = priv_check_cred(cr, PRIV_ROOT, NULL_CRED_OKAY)) != 0)
402 			break;
403 		if (ifp->if_flags & IFF_UP)
404 			error = EBUSY;
405 
406 		bzero(&cfg, sizeof(cfg));
407 		error = copyin((caddr_t)ifr->ifr_data,
408 			       (caddr_t)&cfg,
409 			       sizeof cfg);
410 		if (error) {
411 			/* fall out */
412 		} else if (start_cx28975(sc, cfg) == 0) {
413 			static char  *modstr[] = {
414 				"TCPAM32", "TCPAM16", "TCPAM8", "TCPAM4" };
415 			if_printf(&sc->arpcom.ac_if, "%s, rate %d, %s\n",
416 				cfg.master ? "master" : "slave",
417 				cfg.lrate << 3, modstr[cfg.mod]);
418 		} else {
419 			if_printf(&sc->arpcom.ac_if,
420 				"unable to load firmware\n");
421 			error = EIO;
422 		}
423 		break;
424 
425 	case  SIOCGETSTATS :
426 		if ((error = priv_check_cred(cr, PRIV_ROOT, NULL_CRED_OKAY)) != 0)
427 			break;
428 
429 		t = 0;
430 		if (issue_cx28975_cmd(sc, _DSL_FAR_END_ATTEN, &t, 1))
431 			error = EIO;
432 		ds.attenuat = sc->cmdp->out_data[0];
433 
434 		if (issue_cx28975_cmd(sc, _DSL_NOISE_MARGIN, &t, 1))
435 			error = EIO;
436 		ds.nmr = sc->cmdp->out_data[0];
437 
438 		if (issue_cx28975_cmd(sc, _DSL_POWER_BACK_OFF_RESULT, &t, 1))
439 			error = EIO;
440 		ds.tpbo = sc->cmdp->out_data[0];
441 		ds.rpbo = sc->cmdp->out_data[1];
442 
443 		if (!issue_cx28975_cmd(sc, _DSL_HDSL_PERF_ERR_CTRS, &t, 1)) {
444 			int i;
445 			for (i = 0; i < 10; ++i)
446 				((u_int8_t *) &ds.losw)[i] =
447 					sc->cmdp->out_data[i];
448 		} else {
449 			error = EIO;
450 		}
451 
452 		ds.status_1 = ((volatile u_int8_t *)sc->cmdp)[0x3c0];
453 		ds.status_3 = ((volatile u_int8_t *)sc->cmdp)[0x3c2];
454 
455 		if (error == 0) {
456 			error = copyout(&sc->in_stats,
457 					ifr->ifr_data,
458 					sizeof(struct sbni16_stats));
459 		}
460 		if (error == 0) {
461 			error = copyout(&ds,
462 					(char *)ifr->ifr_data +
463 					 sizeof(struct sbni16_stats),
464 					sizeof(struct dsl_stats));
465 		}
466 		break;
467 
468 	case  SIOCCLRSTATS :
469 		if (!(error = priv_check_cred(cr, PRIV_ROOT, NULL_CRED_OKAY))) {
470 			bzero(&sc->in_stats, sizeof(struct sbni16_stats));
471 			t = 2;
472 			if (issue_cx28975_cmd(sc, _DSL_CLEAR_ERROR_CTRS, &t, 1))
473 				error = EIO;
474 		}
475 		break;
476 	case SIOCSIFFLAGS:
477 		if (ifp->if_flags & IFF_UP) {
478 			if (!(ifp->if_flags & IFF_RUNNING)) {
479 				if (sc->state == NOT_LOADED) {
480 					if_printf(ifp, "firmware wasn't loaded\n");
481 					error = EBUSY;
482 				} else
483 					sbsh_init(sc);
484 			}
485 		} else {
486 			if (ifp->if_flags & IFF_RUNNING) {
487 				sbsh_stop(sc);
488 				ifp->if_flags &= ~IFF_RUNNING;
489 			}
490 		}
491 		break;
492 
493 	case SIOCADDMULTI:
494 	case SIOCDELMULTI:
495 		error = 0;
496 		break;
497 	default:
498 		error = ether_ioctl(ifp, cmd, data);
499 		break;
500 	}
501 	return (error);
502 }
503 
504 
505 static void
506 sbsh_shutdown(device_t dev)
507 {
508 	struct sbsh_softc	*sc = device_get_softc(dev);
509 
510 	lwkt_serialize_enter(sc->arpcom.ac_if.if_serializer);
511 	sbsh_stop(sc);
512 	lwkt_serialize_exit(sc->arpcom.ac_if.if_serializer);
513 }
514 
515 static int
516 sbsh_suspend(device_t dev)
517 {
518 	struct sbsh_softc *sc = device_get_softc(dev);
519 
520 	lwkt_serialize_enter(sc->arpcom.ac_if.if_serializer);
521 	sbsh_stop(sc);
522 	lwkt_serialize_exit(sc->arpcom.ac_if.if_serializer);
523 
524 	return (0);
525 }
526 
527 static int
528 sbsh_resume(device_t dev)
529 {
530 	struct sbsh_softc *sc = device_get_softc(dev);
531 	struct ifnet *ifp = &sc->arpcom.ac_if;
532 
533 	if (ifp->if_flags & IFF_UP)
534 		sbsh_init(sc);
535 
536 	return (0);
537 }
538 
539 
540 static void
541 sbsh_watchdog(struct ifnet *ifp)
542 {
543 	struct sbsh_softc	*sc = ifp->if_softc;
544 
545 	if_printf(ifp, "transmit timeout\n");
546 
547 	if (sc->regs->SR & TXS) {
548 		sc->regs->SR = TXS;
549 		if_printf(ifp, "interrupt posted but not delivered\n");
550 	}
551 	free_sent_buffers(sc);
552 }
553 
554 /* -------------------------------------------------------------------------- */
555 
556 static void
557 sbsh_intr(void *arg)
558 {
559 	struct sbsh_softc  *sc = (struct sbsh_softc *)arg;
560 	u_int8_t  status = sc->regs->SR;
561 
562 	if (status == 0)
563 		return;
564 
565 	if (status & EXT) {
566 		cx28975_interrupt(sc);
567 		sc->regs->SR = EXT;
568 	}
569 
570 	if (status & UFL) {
571 		resume_tx(sc);
572 		sc->regs->SR = UFL;
573 		++sc->in_stats.ufl_errs;
574 		IFNET_STAT_INC(&sc->arpcom.ac_if, oerrors, 1);
575 	}
576 
577 	if (status & RXS) {
578 		sc->regs->SR = RXS;
579 		indicate_frames(sc);
580 		alloc_rx_buffers(sc);
581 	}
582 
583 	if (status & TXS) {
584 		sc->regs->SR = TXS;
585 		free_sent_buffers(sc);
586 	}
587 
588 	if (status & CRC) {
589 		++sc->in_stats.crc_errs;
590 		IFNET_STAT_INC(&sc->arpcom.ac_if, ierrors, 1);
591 		sc->regs->SR = CRC;
592 	}
593 
594 	if (status & OFL) {
595 		++sc->in_stats.ofl_errs;
596 		IFNET_STAT_INC(&sc->arpcom.ac_if, ierrors, 1);
597 		sc->regs->SR = OFL;
598 	}
599 }
600 
601 /*
602  * Look for a first descriptor of a next packet, and write it's number
603  * into CTDR. Then enable the transmitter.
604  */
605 static void
606 resume_tx(struct sbsh_softc *sc)
607 {
608 	u_int32_t	cur_tbd = sc->regs->CTDR;
609 
610 	while (cur_tbd != sc->regs->LTDR
611 		&& (sc->tbd[cur_tbd++].length & LAST_FRAG) == 0)
612 		;
613 	sc->regs->CTDR = cur_tbd;
614 	sc->regs->CR |= TXEN;
615 }
616 
617 static void
618 start_xmit_frames(struct sbsh_softc *sc)
619 {
620 	struct ifnet	*ifp = &sc->arpcom.ac_if;
621 	struct mbuf	*m;
622 
623 	/*
624 	 * Check if we have any free descriptor(s) and free space in
625 	 * our transmit queue.
626 	 */
627 	while (sc->tail_xq != ((sc->head_xq - 1) & (XQLEN - 1))
628 	    && sc->regs->LTDR != ((sc->head_tdesc - 1) & 0x7f)) {
629 
630 		m = ifq_dequeue(&ifp->if_snd);
631 		if (m == NULL)
632 			break;
633 		if (m->m_pkthdr.len) {
634 			BPF_MTAP(ifp, m);
635 			encap_frame(sc, m);
636 		} else
637 			m_freem(m);
638 	}
639 
640 	if (sc->regs->CTDR != sc->regs->LTDR)
641 		ifq_set_oactive(&ifp->if_snd);
642 	else
643 		ifq_clr_oactive(&ifp->if_snd);
644 }
645 
646 
647 static void
648 encap_frame(struct sbsh_softc *sc, struct mbuf *m_head)
649 {
650 	struct mbuf	*m;
651 	u_int32_t	cur_tbd;
652 	int  done;
653 
654 look_for_nonzero:
655 	for (m = m_head; !m->m_len; m = m->m_next)
656 		;
657 
658 	cur_tbd = sc->regs->LTDR & 0x7f;
659 	done = 0;
660 	do {
661 		if (m->m_len < 5 || cur_tbd == ((sc->head_tdesc - 1) & 0x7f)) {
662 			if ((m_head = repack(sc, m_head)) != NULL)
663 				goto look_for_nonzero;
664 			else
665 				return;
666 		}
667 
668 		sc->tbd[cur_tbd].address = vtophys(mtod(m, vm_offset_t));
669 		sc->tbd[cur_tbd].length  = m->m_len;
670 
671 		do {
672 			m = m->m_next;
673 		} while (m && !m->m_len);
674 
675 		if (!m) {	/* last fragment has been reached */
676 			sc->tbd[cur_tbd].length |= LAST_FRAG;
677 			done = 1;
678 		}
679 
680 		++cur_tbd;
681 		cur_tbd &= 0x7f;
682 	} while (!done);
683 
684 	sc->xq[sc->tail_xq++] = m_head;
685 	sc->tail_xq &= (XQLEN - 1);
686 
687 	sc->regs->LTDR = cur_tbd;
688 	++sc->in_stats.sent_pkts;
689 	IFNET_STAT_INC(&sc->arpcom.ac_if, opackets, 1);
690 }
691 
692 static struct mbuf *
693 repack(struct sbsh_softc *sc, struct mbuf *m)
694 {
695 	struct mbuf  *m_new;
696 
697 	MGETHDR(m_new, M_NOWAIT, MT_DATA);
698 	if (!m_new) {
699 		if_printf (&sc->arpcom.ac_if,
700 			   "unable to get mbuf.\n");
701 		return (NULL);
702 	}
703 
704 	if (m->m_pkthdr.len > MHLEN) {
705 		MCLGET(m_new, M_NOWAIT);
706 		if (!(m_new->m_flags & M_EXT)) {
707 			m_freem(m_new);
708 			if_printf (&sc->arpcom.ac_if,
709 				   "unable to get mbuf cluster.\n");
710 			return (NULL);
711 		}
712 	}
713 
714 	m_copydata(m, 0, m->m_pkthdr.len, mtod(m_new, caddr_t));
715 	m_new->m_pkthdr.len = m_new->m_len = m->m_pkthdr.len;
716 	m_freem(m);
717 	return (m_new);
718 }
719 
720 static void
721 free_sent_buffers(struct sbsh_softc *sc)
722 {
723 	u_int32_t  cur_tbd;
724 
725 	cur_tbd = sc->regs->CTDR;
726 
727 	while (sc->head_tdesc != cur_tbd) {
728 		/*
729 		 * Be careful! one element in xq may correspond to
730 		 * multiple descriptors.
731 		 */
732 		if (sc->tbd[sc->head_tdesc].length & LAST_FRAG) {
733 			m_freem(sc->xq[sc->head_xq++]);
734 			sc->head_xq &= (XQLEN - 1);
735 		}
736 
737 		sc->tbd[sc->head_tdesc].length = 0;
738 		sc->head_tdesc = (sc->head_tdesc + 1) & 0x7f;
739 	}
740 
741 	start_xmit_frames(sc);
742 }
743 
744 /*
745  * DON'T use free_sent_buffers to drop the queue!
746  */
747 static void
748 alloc_rx_buffers(struct sbsh_softc *sc)
749 {
750 	unsigned	cur_rbd = sc->regs->LRDR & 0x7f;
751 	struct mbuf	*m;
752 
753 	while (sc->tail_rq != ((sc->head_rq - 1) & (RQLEN - 1))) {
754 		MGETHDR(m, M_NOWAIT, MT_DATA);
755 		if (!m) {
756 			if_printf (&sc->arpcom.ac_if,
757 				   "unable to get mbuf.\n");
758 			return;
759 		}
760 
761 		if (SBNI16_MAX_FRAME > MHLEN) {
762 			MCLGET(m, M_NOWAIT);
763 			if (!(m->m_flags & M_EXT)) {
764 				m_freem(m);
765 				if_printf (&sc->arpcom.ac_if,
766 					   "unable to get mbuf cluster.\n");
767 				return;
768 			}
769 			m->m_pkthdr.len = m->m_len = MCLBYTES;
770 		}
771 
772 		m_adj(m, 2);	/* align ip on longword boundaries */
773 
774 		sc->rq[sc->tail_rq++] = m;
775 		sc->tail_rq &= (RQLEN - 1);
776 
777 		sc->rbd[cur_rbd].address = vtophys(mtod(m, vm_offset_t));
778 		sc->rbd[cur_rbd].length  = 0;
779 		sc->regs->LRDR = cur_rbd = (cur_rbd + 1) & 0x7f;
780 	}
781 }
782 
783 static void
784 indicate_frames(struct sbsh_softc *sc)
785 {
786 	struct ifnet *ifp = &sc->arpcom.ac_if;
787 	unsigned  cur_rbd = sc->regs->CRDR & 0x7f;
788 
789 	while (sc->head_rdesc != cur_rbd) {
790 		struct mbuf  *m = sc->rq[sc->head_rq++];
791 		sc->head_rq &= (RQLEN - 1);
792 
793 		m->m_pkthdr.len = m->m_len =
794 				sc->rbd[sc->head_rdesc].length & 0x7ff;
795 		m->m_pkthdr.rcvif = ifp;
796 
797 		ifp->if_input(ifp, m, NULL, -1);
798 		++sc->in_stats.rcvd_pkts;
799 		IFNET_STAT_INC(ifp, ipackets, 1);
800 
801 		sc->head_rdesc = (sc->head_rdesc + 1) & 0x7f;
802 	}
803 }
804 
805 static void
806 drop_queues(struct sbsh_softc *sc)
807 {
808 	while (sc->head_rq != sc->tail_rq) {
809 		m_freem(sc->rq[sc->head_rq++]);
810 		sc->head_rq &= (RQLEN - 1);
811 	}
812 
813 	while (sc->head_xq != sc->tail_xq) {
814 		m_freem(sc->xq[sc->head_xq++]);
815 		sc->head_xq &= (XQLEN - 1);
816 	}
817 }
818 
819 /* -------------------------------------------------------------------------- */
820 
821 static void
822 activate(struct sbsh_softc *sc)
823 {
824 	struct timeval	tv;
825 
826 	sc->regs->SR   = 0xff;		/* clear it! */
827 	sc->regs->CTDR = sc->regs->LTDR = sc->regs->CRDR = sc->regs->LRDR = 0;
828 
829 	sc->head_tdesc = sc->head_rdesc = 0;
830 	alloc_rx_buffers(sc);
831 
832 	sc->regs->CRB &= ~RXDE;
833 	sc->regs->IMR = EXT | RXS | TXS | CRC | OFL | UFL;
834 	sc->regs->CR |= TXEN | RXEN;
835 
836 	sc->state = ACTIVE;
837 	++sc->in_stats.attempts;
838 	microtime(&tv);
839 	sc->in_stats.last_time = tv.tv_sec;
840 	start_xmit_frames(sc);
841 }
842 
843 static void
844 deactivate(struct sbsh_softc *sc)
845 {
846 	sc->regs->CR &= ~(RXEN | TXEN);
847 	sc->regs->CRB |= RXDE;
848 	sc->regs->IMR  = EXT;
849 	sc->regs->CTDR = sc->regs->LTDR;
850 	sc->regs->CRDR = sc->regs->LRDR;
851 	sc->state = ACTIVATION;
852 
853 	drop_queues(sc);
854 }
855 
856 /* -------------------------------------------------------------------------- */
857 
858 static void
859 cx28975_interrupt(struct sbsh_softc *sc)
860 {
861 	volatile struct cx28975_cmdarea  *p = sc->cmdp;
862 
863 	if (p->intr_host != 0xfe)
864 		return;
865 
866 	if (p->out_ack & 0x80) {
867 		if (*((volatile u_int8_t *)p + 0x3c7) & 2) {
868 			if (sc->state != ACTIVE
869 			    && (*((volatile u_int8_t *)p + 0x3c0) & 0xc0) == 0x40) {
870 				activate(sc);
871 				if_printf(&sc->arpcom.ac_if, "connected to peer\n");
872 			} else if (sc->state == ACTIVE
873 				 && (*((volatile u_int8_t *)p + 0x3c0) & 0xc0) != 0x40) {
874 				deactivate(sc);
875 				if_printf(&sc->arpcom.ac_if, "carrier lost\n");
876 			}
877 		}
878 
879 		p->intr_host = 0;
880 		p->out_ack = 0;
881 	} else {
882 		wakeup(sc);
883 
884 		p->intr_host = 0;
885 	}
886 }
887 
888 /* -------------------------------------------------------------------------- */
889 
890 static int
891 start_cx28975(struct sbsh_softc *sc, struct cx28975_cfg cfg)
892 {
893 	static char  thresh[] = { +8, -4, -16, -40 };
894 
895 	volatile struct cx28975_cmdarea  *p = sc->cmdp;
896 	u_int8_t  t, parm[12];
897 
898 	p->intr_host = 0;
899 	t = p->intr_host;
900 
901 	/* reset chip set */
902 	sc->regs->IMR = EXT;
903 	sc->regs->CR  = 0;
904 	sc->regs->SR  = 0xff;
905 	DELAY(2);
906 	sc->regs->CR = XRST;
907 	if (cfg.crc16)
908 		sc->regs->CR |= CMOD;
909 	if (cfg.fill_7e)
910 		sc->regs->CR |= FMOD;
911 	if (cfg.inv)
912 		sc->regs->CR |= PMOD;
913 
914 	sc->regs->CRB |= RODD | RXDE;
915 	if (cfg.rburst)
916 		sc->regs->CRB |= RDBE;
917 	if (cfg.wburst)
918 		sc->regs->CRB |= WTBE;
919 
920 	tsleep(sc, 0, "sbsh", 0);
921 	if ((p->out_ack & 0x1f) != _ACK_BOOT_WAKE_UP)
922 		return (-1);
923 
924 	if (download_firmware(sc, cfg.firmw_image, cfg.firmw_len))
925 		return (-1);
926 
927 	tsleep(sc, 0, "sbsh", 0);
928 	if ((p->out_ack & 0x1f) != _ACK_OPER_WAKE_UP)
929 		return (-1);
930 
931 	t = cfg.master ? 1 : 9;
932 	if (issue_cx28975_cmd(sc, _DSL_SYSTEM_ENABLE, &t, 1))
933 		return (-1);
934 
935 	t = 0x63;
936 	if (issue_cx28975_cmd(sc, _DSL_SYSTEM_CONFIG, &t, 1))
937 		return (-1);
938 
939 	*(u_int16_t *)parm = cfg.lrate >> 3;
940 	parm[2] = parm[3] = parm[0];
941 	parm[5] = cfg.lrate & 7;
942 	parm[4] = parm[7] = 1;
943 	parm[6] = 0;
944 	if (issue_cx28975_cmd(sc, _DSL_MULTI_RATE_CONFIG, parm, 8))
945 		return (-1);
946 
947 	parm[0] = 0x02 | (cfg.mod << 4);
948 	parm[1] = 0;
949 	if (issue_cx28975_cmd(sc, _DSL_TRAINING_MODE, parm, 2))
950 		return (-1);
951 
952 	bzero(parm, 12);
953 	parm[0] = 0x04;		/* pre-activation: G.hs */
954 	parm[4] = 0x04;		/* no remote configuration */
955 	parm[7] = 0x01;		/* annex A (default) */
956 	parm[8] = 0xff;		/* i-bit mask (all bits) */
957 	if (issue_cx28975_cmd(sc, _DSL_PREACTIVATION_CFG, parm, 12))
958 		return (-1);
959 
960 	parm[0] = 0x03;		/* dying gasp time - 3 frames */
961 	parm[1] = thresh[cfg.mod];
962 	parm[2] = 0xff;		/* attenuation */
963 	parm[3] = 0x04;		/* line probe NMR (+2 dB) */
964 	parm[4] = 0x00;		/* reserved */
965 	parm[5] = 0x00;
966 	if (issue_cx28975_cmd(sc, _DSL_THRESHOLDS, parm, 6))
967 		return (-1);
968 
969 	t = cfg.master ? 0x23 : 0x21;
970 	if (issue_cx28975_cmd(sc, _DSL_FR_PCM_CONFIG, &t, 1))
971 		return (-1);
972 
973 	t = 0x02;
974 	if (issue_cx28975_cmd(sc, _DSL_INTR_HOST_MASK, &t, 1))
975 		return (-1);
976 
977 	sc->state = DOWN;
978 	return (0);
979 }
980 
981 static int
982 download_firmware(struct sbsh_softc *sc, u_int8_t *img, u_int32_t img_len)
983 {
984 	u_int32_t	t;
985 	int		i;
986 	u_int8_t	cksum = 0;
987 
988 	for (i = 0; i < img_len; ++i)
989 		cksum += img[i];
990 
991 	t = img_len;
992 	if (issue_cx28975_cmd(sc, _DSL_DOWNLOAD_START, (u_int8_t *) &t, 4))
993 		return (-1);
994 
995 	for (i = 0; img_len >= 75; i += 75, img_len -= 75) {
996 		if (issue_cx28975_cmd(sc, _DSL_DOWNLOAD_DATA, img + i, 75))
997 			return (-1);
998 	}
999 
1000 	if (img_len
1001 	    &&  issue_cx28975_cmd(sc, _DSL_DOWNLOAD_DATA, img + i, img_len))
1002 		return (-1);
1003 
1004 	t = (cksum ^ 0xff) + 1;
1005 	if (issue_cx28975_cmd(sc, _DSL_DOWNLOAD_END, (u_int8_t *) &t, 1))
1006 		return (-1);
1007 
1008 	return (0);
1009 }
1010 
1011 static int
1012 issue_cx28975_cmd(struct sbsh_softc *sc, u_int8_t cmd,
1013 			u_int8_t *data, u_int8_t size)
1014 {
1015 	volatile struct cx28975_cmdarea  *p = sc->cmdp;
1016 	volatile u_int8_t  *databuf = p->in_data;
1017 	int  i;
1018 
1019 	u_int8_t  cksum = 0;
1020 
1021 	p->in_dest	= 0xf0;
1022 	p->in_opcode	= cmd;
1023 	p->in_zero	= 0;
1024 	p->in_length	= --size;
1025 	p->in_csum	= 0xf0 ^ cmd ^ size ^ 0xaa;
1026 
1027 	for (i = 0; i <= size; ++i) {
1028 		cksum ^= *data;
1029 		*databuf++ = *data++;	/* only 1 byte per cycle! */
1030 	}
1031 
1032 	p->in_datasum	= cksum ^ 0xaa;
1033 	p->out_ack	= _ACK_NOT_COMPLETE;
1034 	p->intr_8051	= 0xfe;
1035 
1036 	if (tsleep(sc, 0, "sbsh", hz << 3))
1037 		return (-1);
1038 
1039 	while (p->out_ack == _ACK_NOT_COMPLETE)
1040 		;					/* FIXME ! */
1041 
1042 	if ((p->out_ack & 0x1f) == _ACK_PASS) {
1043 		p->out_ack = 0;
1044 		return (0);
1045 	} else {
1046 		p->out_ack = 0;
1047 		return (-1);
1048 	}
1049 }
1050