xref: /csrg-svn/sys/vax/if/if_en.c (revision 19864)
1 /*	if_en.c	6.6	85/05/01	*/
2 
3 #include "en.h"
4 
5 /*
6  * Xerox prototype (3 Mb) Ethernet interface driver.
7  */
8 #include "../machine/pte.h"
9 
10 #include "param.h"
11 #include "systm.h"
12 #include "mbuf.h"
13 #include "buf.h"
14 #include "protosw.h"
15 #include "socket.h"
16 #include "vmmac.h"
17 #include "errno.h"
18 #include "ioctl.h"
19 
20 #include "../net/if.h"
21 #include "../net/netisr.h"
22 #include "../net/route.h"
23 #include "../netinet/in.h"
24 #include "../netinet/in_systm.h"
25 #include "../netinet/in_var.h"
26 #include "../netinet/ip.h"
27 #include "../netinet/ip_var.h"
28 #include "../netpup/pup.h"
29 #include "../netpup/ether.h"
30 
31 #include "../vax/cpu.h"
32 #include "../vax/mtpr.h"
33 #include "if_en.h"
34 #include "if_enreg.h"
35 #include "if_uba.h"
36 #include "../vaxuba/ubareg.h"
37 #include "../vaxuba/ubavar.h"
38 
39 #define	ENMTU	(1024+512)
40 #define	ENMRU	(1024+512+16)		/* 16 is enough to receive trailer */
41 
42 int	enprobe(), enattach(), enrint(), enxint(), encollide();
43 struct	uba_device *eninfo[NEN];
44 u_short enstd[] = { 0 };
45 struct	uba_driver endriver =
46 	{ enprobe, 0, enattach, 0, enstd, "en", eninfo };
47 #define	ENUNIT(x)	minor(x)
48 
49 int	eninit(),enoutput(),enreset(),enioctl();
50 
51 #ifdef notdef
52 /*
53  * If you need to byte swap IP's in the system, define
54  * this and do a SIOCSIFFLAGS at boot time.
55  */
56 #define	ENF_SWABIPS	0x1000
57 #endif
58 
59 /*
60  * Ethernet software status per interface.
61  *
62  * Each interface is referenced by a network interface structure,
63  * es_if, which the routing code uses to locate the interface.
64  * This structure contains the output queue for the interface, its address, ...
65  * We also have, for each interface, a UBA interface structure, which
66  * contains information about the UNIBUS resources held by the interface:
67  * map registers, buffered data paths, etc.  Information is cached in this
68  * structure for use by the if_uba.c routines in running the interface
69  * efficiently.
70  */
71 struct	en_softc {
72 	struct	ifnet es_if;		/* network-visible interface */
73 	struct	ifuba es_ifuba;		/* UNIBUS resources */
74 	short	es_host;		/* hardware host number */
75 	short	es_delay;		/* current output delay */
76 	short	es_mask;		/* mask for current output delay */
77 	short	es_lastx;		/* host last transmitted to */
78 	short	es_oactive;		/* is output active? */
79 	short	es_olen;		/* length of last output */
80 } en_softc[NEN];
81 
82 /*
83  * Do output DMA to determine interface presence and
84  * interrupt vector.  DMA is too short to disturb other hosts.
85  */
86 enprobe(reg)
87 	caddr_t reg;
88 {
89 	register int br, cvec;		/* r11, r10 value-result */
90 	register struct endevice *addr = (struct endevice *)reg;
91 
92 #ifdef lint
93 	br = 0; cvec = br; br = cvec;
94 	enrint(0); enxint(0); encollide(0);
95 #endif
96 	addr->en_istat = 0;
97 	addr->en_owc = -1;
98 	addr->en_oba = 0;
99 	addr->en_ostat = EN_IEN|EN_GO;
100 	DELAY(100000);
101 	addr->en_ostat = 0;
102 	return (1);
103 }
104 
105 /*
106  * Interface exists: make available by filling in network interface
107  * record.  System will initialize the interface when it is ready
108  * to accept packets.
109  */
110 enattach(ui)
111 	struct uba_device *ui;
112 {
113 	register struct en_softc *es = &en_softc[ui->ui_unit];
114 
115 	es->es_if.if_unit = ui->ui_unit;
116 	es->es_if.if_name = "en";
117 	es->es_if.if_mtu = ENMTU;
118 	es->es_if.if_flags = IFF_BROADCAST;
119 	es->es_if.if_init = eninit;
120 	es->es_if.if_output = enoutput;
121 	es->es_if.if_ioctl = enioctl;
122 	es->es_if.if_reset = enreset;
123 	es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT;
124 #if defined(VAX750)
125 	/* don't chew up 750 bdp's */
126 	if (cpu == VAX_750 && ui->ui_unit > 0)
127 		es->es_ifuba.ifu_flags &= ~UBA_NEEDBDP;
128 #endif
129 	if_attach(&es->es_if);
130 }
131 
132 /*
133  * Reset of interface after UNIBUS reset.
134  * If interface is on specified uba, reset its state.
135  */
136 enreset(unit, uban)
137 	int unit, uban;
138 {
139 	register struct uba_device *ui;
140 
141 	if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
142 	    ui->ui_ubanum != uban)
143 		return;
144 	printf(" en%d", unit);
145 	eninit(unit);
146 }
147 
148 /*
149  * Initialization of interface; clear recorded pending
150  * operations, and reinitialize UNIBUS usage.
151  */
152 eninit(unit)
153 	int unit;
154 {
155 	register struct en_softc *es = &en_softc[unit];
156 	register struct uba_device *ui = eninfo[unit];
157 	register struct endevice *addr;
158 	int s;
159 
160 	if (es->es_if.if_addrlist == (struct ifaddr *)0)
161 		return;
162 	if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,
163 	    sizeof (struct en_header), (int)btoc(ENMRU)) == 0) {
164 		printf("en%d: can't initialize\n", unit);
165 		es->es_if.if_flags &= ~IFF_UP;
166 		return;
167 	}
168 	addr = (struct endevice *)ui->ui_addr;
169 	addr->en_istat = addr->en_ostat = 0;
170 
171 	/*
172 	 * Hang a receive and start any
173 	 * pending writes by faking a transmit complete.
174 	 */
175 	s = splimp();
176 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
177 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
178 	addr->en_istat = EN_IEN|EN_GO;
179 	es->es_oactive = 1;
180 	es->es_if.if_flags |= IFF_RUNNING;
181 	enxint(unit);
182 	splx(s);
183 }
184 
185 int	enalldelay = 0;
186 int	enlastdel = 50;
187 int	enlastmask = (~0) << 5;
188 
189 /*
190  * Start or restart output on interface.
191  * If interface is already active, then this is a retransmit
192  * after a collision, and just restuff registers and delay.
193  * If interface is not already active, get another datagram
194  * to send off of the interface queue, and map it to the interface
195  * before starting the output.
196  */
197 enstart(dev)
198 	dev_t dev;
199 {
200         int unit = ENUNIT(dev);
201 	struct uba_device *ui = eninfo[unit];
202 	register struct en_softc *es = &en_softc[unit];
203 	register struct endevice *addr;
204 	register struct en_header *en;
205 	struct mbuf *m;
206 	int dest;
207 
208 	if (es->es_oactive)
209 		goto restart;
210 
211 	/*
212 	 * Not already active: dequeue another request
213 	 * and map it to the UNIBUS.  If no more requests,
214 	 * just return.
215 	 */
216 	IF_DEQUEUE(&es->es_if.if_snd, m);
217 	if (m == 0) {
218 		es->es_oactive = 0;
219 		return;
220 	}
221 	en = mtod(m, struct en_header *);
222 	dest = en->en_dhost;
223 	en->en_shost = es->es_host;
224 	es->es_olen = if_wubaput(&es->es_ifuba, m);
225 #ifdef ENF_SWABIPS
226 	/*
227 	 * The Xerox interface does word at a time DMA, so
228 	 * someone must do byte swapping of user data if high
229 	 * and low ender machines are to communicate.  It doesn't
230 	 * belong here, but certain people depend on it, so...
231 	 *
232 	 * Should swab everybody, but this is a kludge anyway.
233 	 */
234 	if (es->es_if.if_flags & ENF_SWABIPS) {
235 		en = (struct en_header *)es->es_ifuba.ifu_w.ifrw_addr;
236 		if (en->en_type == ENTYPE_IP)
237 			enswab((caddr_t)(en + 1), (caddr_t)(en + 1),
238 			    es->es_olen - sizeof (struct en_header) + 1);
239 	}
240 #endif
241 
242 	/*
243 	 * Ethernet cannot take back-to-back packets (no
244 	 * buffering in interface.  To help avoid overrunning
245 	 * receivers, enforce a small delay (about 1ms) in interface:
246 	 *	* between all packets when enalldelay
247 	 *	* whenever last packet was broadcast
248 	 *	* whenever this packet is to same host as last packet
249 	 */
250 	if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) {
251 		es->es_delay = enlastdel;
252 		es->es_mask = enlastmask;
253 	}
254 	es->es_lastx = dest;
255 
256 restart:
257 	/*
258 	 * Have request mapped to UNIBUS for transmission.
259 	 * Purge any stale data from this BDP, and start the otput.
260 	 */
261 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
262 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);
263 	addr = (struct endevice *)ui->ui_addr;
264 	addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
265 	addr->en_odelay = es->es_delay;
266 	addr->en_owc = -((es->es_olen + 1) >> 1);
267 	addr->en_ostat = EN_IEN|EN_GO;
268 	es->es_oactive = 1;
269 }
270 
271 /*
272  * Ethernet interface transmitter interrupt.
273  * Start another output if more data to send.
274  */
275 enxint(unit)
276 	int unit;
277 {
278 	register struct uba_device *ui = eninfo[unit];
279 	register struct en_softc *es = &en_softc[unit];
280 	register struct endevice *addr = (struct endevice *)ui->ui_addr;
281 
282 	if (es->es_oactive == 0)
283 		return;
284 	if (es->es_mask && (addr->en_ostat&EN_OERROR)) {
285 		es->es_if.if_oerrors++;
286 		endocoll(unit);
287 		return;
288 	}
289 	es->es_if.if_opackets++;
290 	es->es_oactive = 0;
291 	es->es_delay = 0;
292 	es->es_mask = ~0;
293 	if (es->es_ifuba.ifu_xtofree) {
294 		m_freem(es->es_ifuba.ifu_xtofree);
295 		es->es_ifuba.ifu_xtofree = 0;
296 	}
297 	if (es->es_if.if_snd.ifq_head == 0) {
298 		es->es_lastx = 256;		/* putatively illegal */
299 		return;
300 	}
301 	enstart(unit);
302 }
303 
304 /*
305  * Collision on ethernet interface.  Do exponential
306  * backoff, and retransmit.  If have backed off all
307  * the way print warning diagnostic, and drop packet.
308  */
309 encollide(unit)
310 	int unit;
311 {
312 	struct en_softc *es = &en_softc[unit];
313 
314 	es->es_if.if_collisions++;
315 	if (es->es_oactive == 0)
316 		return;
317 	endocoll(unit);
318 }
319 
320 endocoll(unit)
321 	int unit;
322 {
323 	register struct en_softc *es = &en_softc[unit];
324 
325 	/*
326 	 * Es_mask is a 16 bit number with n low zero bits, with
327 	 * n the number of backoffs.  When es_mask is 0 we have
328 	 * backed off 16 times, and give up.
329 	 */
330 	if (es->es_mask == 0) {
331 		printf("en%d: send error\n", unit);
332 		enxint(unit);
333 		return;
334 	}
335 	/*
336 	 * Another backoff.  Restart with delay based on n low bits
337 	 * of the interval timer.
338 	 */
339 	es->es_mask <<= 1;
340 	es->es_delay = mfpr(ICR) &~ es->es_mask;
341 	enstart(unit);
342 }
343 
344 #ifdef notdef
345 struct	sockproto enproto = { AF_ETHERLINK };
346 struct	sockaddr_en endst = { AF_ETHERLINK };
347 struct	sockaddr_en ensrc = { AF_ETHERLINK };
348 #endif
349 /*
350  * Ethernet interface receiver interrupt.
351  * If input error just drop packet.
352  * Otherwise purge input buffered data path and examine
353  * packet to determine type.  If can't determine length
354  * from type, then have to drop packet.  Othewise decapsulate
355  * packet based on type and pass to type specific higher-level
356  * input routine.
357  */
358 enrint(unit)
359 	int unit;
360 {
361 	register struct en_softc *es = &en_softc[unit];
362 	struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
363 	register struct en_header *en;
364     	struct mbuf *m;
365 	int len; short resid;
366 	register struct ifqueue *inq;
367 	int off, s;
368 
369 	es->es_if.if_ipackets++;
370 
371 	/*
372 	 * Purge BDP; drop if input error indicated.
373 	 */
374 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
375 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);
376 	if (addr->en_istat&EN_IERROR) {
377 		es->es_if.if_ierrors++;
378 		goto setup;
379 	}
380 
381 	/*
382 	 * Calculate input data length.
383 	 * Get pointer to ethernet header (in input buffer).
384 	 * Deal with trailer protocol: if type is PUP trailer
385 	 * get true type from first 16-bit word past data.
386 	 * Remember that type was trailer by setting off.
387 	 */
388 	resid = addr->en_iwc;
389 	if (resid)
390 		resid |= 0176000;
391 	len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1;
392 	len -= sizeof (struct en_header);
393 	if (len > ENMRU)
394 		goto setup;			/* sanity */
395 	en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
396 	en->en_type = ntohs(en->en_type);
397 #define	endataaddr(en, off, type)	((type)(((caddr_t)((en)+1)+(off))))
398 	if (en->en_type >= ENTYPE_TRAIL &&
399 	    en->en_type < ENTYPE_TRAIL+ENTYPE_NTRAILER) {
400 		off = (en->en_type - ENTYPE_TRAIL) * 512;
401 		if (off > ENMTU)
402 			goto setup;		/* sanity */
403 		en->en_type = ntohs(*endataaddr(en, off, u_short *));
404 		resid = ntohs(*(endataaddr(en, off+2, u_short *)));
405 		if (off + resid > len)
406 			goto setup;		/* sanity */
407 		len = off + resid;
408 	} else
409 		off = 0;
410 	if (len == 0)
411 		goto setup;
412 #ifdef ENF_SWABIPS
413 	if (es->es_if.if_flags & ENF_SWABIPS && en->en_type == ENTYPE_IP)
414 		enswab((caddr_t)(en + 1), (caddr_t)(en + 1), len);
415 #endif
416 	/*
417 	 * Pull packet off interface.  Off is nonzero if packet
418 	 * has trailing header; if_rubaget will then force this header
419 	 * information to be at the front, but we still have to drop
420 	 * the type and length which are at the front of any trailer data.
421 	 */
422 	m = if_rubaget(&es->es_ifuba, len, off);
423 	if (m == 0)
424 		goto setup;
425 	if (off) {
426 		m->m_off += 2 * sizeof (u_short);
427 		m->m_len -= 2 * sizeof (u_short);
428 	}
429 	switch (en->en_type) {
430 
431 #ifdef INET
432 	case ENTYPE_IP:
433 		schednetisr(NETISR_IP);
434 		inq = &ipintrq;
435 		break;
436 #endif
437 #ifdef PUP
438 	case ENTYPE_PUP:
439 		rpup_input(m);
440 		goto setup;
441 #endif
442 	default:
443 #ifdef notdef
444 		enproto.sp_protocol = en->en_type;
445 		endst.sen_host = en->en_dhost;
446 		endst.sen_net = ensrc.sen_net = es->es_if.if_net;
447 		ensrc.sen_host = en->en_shost;
448 		raw_input(m, &enproto,
449 		    (struct sockaddr *)&ensrc, (struct sockaddr *)&endst);
450 #else
451 		m_freem(m);
452 #endif
453 		goto setup;
454 	}
455 
456 	s = splimp();
457 	if (IF_QFULL(inq)) {
458 		IF_DROP(inq);
459 		m_freem(m);
460 	} else
461 		IF_ENQUEUE(inq, m);
462 	splx(s);
463 
464 setup:
465 	/*
466 	 * Reset for next packet.
467 	 */
468 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
469 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
470 	addr->en_istat = EN_IEN|EN_GO;
471 }
472 
473 /*
474  * Ethernet output routine.
475  * Encapsulate a packet of type family for the local net.
476  * Use trailer local net encapsulation if enough data in first
477  * packet leaves a multiple of 512 bytes of data in remainder.
478  */
479 enoutput(ifp, m0, dst)
480 	struct ifnet *ifp;
481 	struct mbuf *m0;
482 	struct sockaddr *dst;
483 {
484 	int type, dest, s, error;
485 	register struct mbuf *m = m0;
486 	register struct en_header *en;
487 	register int off;
488 
489 	switch (dst->sa_family) {
490 
491 #ifdef INET
492 	case AF_INET:
493 		{
494 		struct in_addr in;
495 
496 		in = ((struct sockaddr_in *)dst)->sin_addr;
497 		if (in_broadcast(in))
498 			dest = EN_BROADCAST;
499 		else
500 			dest = in_lnaof(in);
501 		}
502 		if (dest >= 0x100) {
503 			error = EPERM;		/* ??? */
504 			goto bad;
505 		}
506 		off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
507 		/* need per host negotiation */
508 		if ((ifp->if_flags & IFF_NOTRAILERS) == 0)
509 		if (off > 0 && (off & 0x1ff) == 0 &&
510 		    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {
511 			type = ENTYPE_TRAIL + (off>>9);
512 			m->m_off -= 2 * sizeof (u_short);
513 			m->m_len += 2 * sizeof (u_short);
514 			*mtod(m, u_short *) = htons((u_short)ENTYPE_IP);
515 			*(mtod(m, u_short *) + 1) = ntohs((u_short)m->m_len);
516 			goto gottrailertype;
517 		}
518 		type = ENTYPE_IP;
519 		off = 0;
520 		goto gottype;
521 #endif
522 #ifdef PUP
523 	case AF_PUP:
524 		dest = ((struct sockaddr_pup *)dst)->spup_host;
525 		type = ENTYPE_PUP;
526 		off = 0;
527 		goto gottype;
528 #endif
529 
530 #ifdef notdef
531 	case AF_ETHERLINK:
532 		goto gotheader;
533 #endif
534 
535 	default:
536 		printf("en%d: can't handle af%d\n", ifp->if_unit,
537 			dst->sa_family);
538 		error = EAFNOSUPPORT;
539 		goto bad;
540 	}
541 
542 gottrailertype:
543 	/*
544 	 * Packet to be sent as trailer: move first packet
545 	 * (control information) to end of chain.
546 	 */
547 	while (m->m_next)
548 		m = m->m_next;
549 	m->m_next = m0;
550 	m = m0->m_next;
551 	m0->m_next = 0;
552 	m0 = m;
553 
554 gottype:
555 	/*
556 	 * Add local net header.  If no space in first mbuf,
557 	 * allocate another.
558 	 */
559 	if (m->m_off > MMAXOFF ||
560 	    MMINOFF + sizeof (struct en_header) > m->m_off) {
561 		MGET(m, M_DONTWAIT, MT_HEADER);
562 		if (m == 0) {
563 			error = ENOBUFS;
564 			goto bad;
565 		}
566 		m->m_next = m0;
567 		m->m_off = MMINOFF;
568 		m->m_len = sizeof (struct en_header);
569 	} else {
570 		m->m_off -= sizeof (struct en_header);
571 		m->m_len += sizeof (struct en_header);
572 	}
573 	en = mtod(m, struct en_header *);
574 	/* add en_shost later */
575 	en->en_dhost = dest;
576 	en->en_type = htons((u_short)type);
577 
578 gotheader:
579 	/*
580 	 * Queue message on interface, and start output if interface
581 	 * not yet active.
582 	 */
583 	s = splimp();
584 	if (IF_QFULL(&ifp->if_snd)) {
585 		IF_DROP(&ifp->if_snd);
586 		error = ENOBUFS;
587 		goto qfull;
588 	}
589 	IF_ENQUEUE(&ifp->if_snd, m);
590 	if (en_softc[ifp->if_unit].es_oactive == 0)
591 		enstart(ifp->if_unit);
592 	splx(s);
593 	return (0);
594 qfull:
595 	m0 = m;
596 	splx(s);
597 bad:
598 	m_freem(m0);
599 	return (error);
600 }
601 
602 /*
603  * Process an ioctl request.
604  */
605 enioctl(ifp, cmd, data)
606 	register struct ifnet *ifp;
607 	int cmd;
608 	caddr_t data;
609 {
610 	register struct en_softc *es = ((struct en_softc *)ifp);
611 	struct ifaddr *ifa = (struct ifaddr *) data;
612 	int s = splimp(), error = 0;
613 	struct endevice *enaddr;
614 
615 	switch (cmd) {
616 
617 	case SIOCSIFADDR:
618 		enaddr = (struct endevice *)eninfo[ifp->if_unit]->ui_addr;
619 		es->es_host = (~enaddr->en_addr) & 0xff;
620 		/*
621 		 * Attempt to check agreement of protocol address
622 		 * and board address.
623 		 */
624 		switch (ifa->ifa_addr.sa_family) {
625 		case AF_INET:
626 			if (in_lnaof(IA_SIN(ifa)->sin_addr) != es->es_host)
627 				return (EADDRNOTAVAIL);
628 			break;
629 		}
630 		ifp->if_flags |= IFF_UP;
631 		if ((ifp->if_flags & IFF_RUNNING) == 0)
632 			eninit(ifp->if_unit);
633 		break;
634 
635 	default:
636 		error = EINVAL;
637 	}
638 	splx(s);
639 	return (error);
640 }
641 
642 #ifdef ENF_SWABIPS
643 /*
644  * Swab bytes
645  * Jeffrey Mogul, Stanford
646  */
647 enswab(from, to, n)
648 	register unsigned char *from, *to;
649 	register int n;
650 {
651 	register unsigned long temp;
652 
653 	if ((n <= 0) || (n > 0xFFFF)) {
654 		printf("enswab: bad len %d\n", n);
655 		return;
656 	}
657 
658 	n >>= 1; n++;
659 #define	STEP	{temp = *from++;*to++ = *from++;*to++ = temp;}
660 	/* round to multiple of 8 */
661 	while ((--n) & 07)
662 		STEP;
663 	n >>= 3;
664 	while (--n >= 0) {
665 		STEP; STEP; STEP; STEP;
666 		STEP; STEP; STEP; STEP;
667 	}
668 }
669 #endif
670