xref: /original-bsd/sys/vax/if/if_en.c (revision 7ecb520c)
1 /*	if_en.c	6.7	85/05/04	*/
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 #ifdef PUP
29 #include "../netpup/pup.h"
30 #include "../netpup/ether.h"
31 #endif
32 
33 #include "../vax/cpu.h"
34 #include "../vax/mtpr.h"
35 #include "if_en.h"
36 #include "if_enreg.h"
37 #include "if_uba.h"
38 #include "../vaxuba/ubareg.h"
39 #include "../vaxuba/ubavar.h"
40 
41 #define	ENMTU	(1024+512)
42 #define	ENMRU	(1024+512+16)		/* 16 is enough to receive trailer */
43 
44 int	enprobe(), enattach(), enrint(), enxint(), encollide();
45 struct	uba_device *eninfo[NEN];
46 u_short enstd[] = { 0 };
47 struct	uba_driver endriver =
48 	{ enprobe, 0, enattach, 0, enstd, "en", eninfo };
49 #define	ENUNIT(x)	minor(x)
50 
51 int	eninit(),enoutput(),enreset(),enioctl();
52 
53 #ifdef notdef
54 /*
55  * If you need to byte swap IP's in the system, define
56  * this and do a SIOCSIFFLAGS at boot time.
57  */
58 #define	ENF_SWABIPS	0x1000
59 #endif
60 
61 /*
62  * Ethernet software status per interface.
63  *
64  * Each interface is referenced by a network interface structure,
65  * es_if, which the routing code uses to locate the interface.
66  * This structure contains the output queue for the interface, its address, ...
67  * We also have, for each interface, a UBA interface structure, which
68  * contains information about the UNIBUS resources held by the interface:
69  * map registers, buffered data paths, etc.  Information is cached in this
70  * structure for use by the if_uba.c routines in running the interface
71  * efficiently.
72  */
73 struct	en_softc {
74 	struct	ifnet es_if;		/* network-visible interface */
75 	struct	ifuba es_ifuba;		/* UNIBUS resources */
76 	short	es_host;		/* hardware host number */
77 	short	es_delay;		/* current output delay */
78 	short	es_mask;		/* mask for current output delay */
79 	short	es_lastx;		/* host last transmitted to */
80 	short	es_oactive;		/* is output active? */
81 	short	es_olen;		/* length of last output */
82 } en_softc[NEN];
83 
84 /*
85  * Do output DMA to determine interface presence and
86  * interrupt vector.  DMA is too short to disturb other hosts.
87  */
88 enprobe(reg)
89 	caddr_t reg;
90 {
91 	register int br, cvec;		/* r11, r10 value-result */
92 	register struct endevice *addr = (struct endevice *)reg;
93 
94 #ifdef lint
95 	br = 0; cvec = br; br = cvec;
96 	enrint(0); enxint(0); encollide(0);
97 #endif
98 	addr->en_istat = 0;
99 	addr->en_owc = -1;
100 	addr->en_oba = 0;
101 	addr->en_ostat = EN_IEN|EN_GO;
102 	DELAY(100000);
103 	addr->en_ostat = 0;
104 	return (1);
105 }
106 
107 /*
108  * Interface exists: make available by filling in network interface
109  * record.  System will initialize the interface when it is ready
110  * to accept packets.
111  */
112 enattach(ui)
113 	struct uba_device *ui;
114 {
115 	register struct en_softc *es = &en_softc[ui->ui_unit];
116 
117 	es->es_if.if_unit = ui->ui_unit;
118 	es->es_if.if_name = "en";
119 	es->es_if.if_mtu = ENMTU;
120 	es->es_if.if_flags = IFF_BROADCAST;
121 	es->es_if.if_init = eninit;
122 	es->es_if.if_output = enoutput;
123 	es->es_if.if_ioctl = enioctl;
124 	es->es_if.if_reset = enreset;
125 	es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT;
126 #if defined(VAX750)
127 	/* don't chew up 750 bdp's */
128 	if (cpu == VAX_750 && ui->ui_unit > 0)
129 		es->es_ifuba.ifu_flags &= ~UBA_NEEDBDP;
130 #endif
131 	if_attach(&es->es_if);
132 }
133 
134 /*
135  * Reset of interface after UNIBUS reset.
136  * If interface is on specified uba, reset its state.
137  */
138 enreset(unit, uban)
139 	int unit, uban;
140 {
141 	register struct uba_device *ui;
142 
143 	if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
144 	    ui->ui_ubanum != uban)
145 		return;
146 	printf(" en%d", unit);
147 	eninit(unit);
148 }
149 
150 /*
151  * Initialization of interface; clear recorded pending
152  * operations, and reinitialize UNIBUS usage.
153  */
154 eninit(unit)
155 	int unit;
156 {
157 	register struct en_softc *es = &en_softc[unit];
158 	register struct uba_device *ui = eninfo[unit];
159 	register struct endevice *addr;
160 	int s;
161 
162 	if (es->es_if.if_addrlist == (struct ifaddr *)0)
163 		return;
164 	if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,
165 	    sizeof (struct en_header), (int)btoc(ENMRU)) == 0) {
166 		printf("en%d: can't initialize\n", unit);
167 		es->es_if.if_flags &= ~IFF_UP;
168 		return;
169 	}
170 	addr = (struct endevice *)ui->ui_addr;
171 	addr->en_istat = addr->en_ostat = 0;
172 
173 	/*
174 	 * Hang a receive and start any
175 	 * pending writes by faking a transmit complete.
176 	 */
177 	s = splimp();
178 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
179 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
180 	addr->en_istat = EN_IEN|EN_GO;
181 	es->es_oactive = 1;
182 	es->es_if.if_flags |= IFF_RUNNING;
183 	enxint(unit);
184 	splx(s);
185 }
186 
187 int	enalldelay = 0;
188 int	enlastdel = 50;
189 int	enlastmask = (~0) << 5;
190 
191 /*
192  * Start or restart output on interface.
193  * If interface is already active, then this is a retransmit
194  * after a collision, and just restuff registers and delay.
195  * If interface is not already active, get another datagram
196  * to send off of the interface queue, and map it to the interface
197  * before starting the output.
198  */
199 enstart(dev)
200 	dev_t dev;
201 {
202         int unit = ENUNIT(dev);
203 	struct uba_device *ui = eninfo[unit];
204 	register struct en_softc *es = &en_softc[unit];
205 	register struct endevice *addr;
206 	register struct en_header *en;
207 	struct mbuf *m;
208 	int dest;
209 
210 	if (es->es_oactive)
211 		goto restart;
212 
213 	/*
214 	 * Not already active: dequeue another request
215 	 * and map it to the UNIBUS.  If no more requests,
216 	 * just return.
217 	 */
218 	IF_DEQUEUE(&es->es_if.if_snd, m);
219 	if (m == 0) {
220 		es->es_oactive = 0;
221 		return;
222 	}
223 	en = mtod(m, struct en_header *);
224 	dest = en->en_dhost;
225 	en->en_shost = es->es_host;
226 	es->es_olen = if_wubaput(&es->es_ifuba, m);
227 #ifdef ENF_SWABIPS
228 	/*
229 	 * The Xerox interface does word at a time DMA, so
230 	 * someone must do byte swapping of user data if high
231 	 * and low ender machines are to communicate.  It doesn't
232 	 * belong here, but certain people depend on it, so...
233 	 *
234 	 * Should swab everybody, but this is a kludge anyway.
235 	 */
236 	if (es->es_if.if_flags & ENF_SWABIPS) {
237 		en = (struct en_header *)es->es_ifuba.ifu_w.ifrw_addr;
238 		if (en->en_type == ENTYPE_IP)
239 			enswab((caddr_t)(en + 1), (caddr_t)(en + 1),
240 			    es->es_olen - sizeof (struct en_header) + 1);
241 	}
242 #endif
243 
244 	/*
245 	 * Ethernet cannot take back-to-back packets (no
246 	 * buffering in interface.  To help avoid overrunning
247 	 * receivers, enforce a small delay (about 1ms) in interface:
248 	 *	* between all packets when enalldelay
249 	 *	* whenever last packet was broadcast
250 	 *	* whenever this packet is to same host as last packet
251 	 */
252 	if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) {
253 		es->es_delay = enlastdel;
254 		es->es_mask = enlastmask;
255 	}
256 	es->es_lastx = dest;
257 
258 restart:
259 	/*
260 	 * Have request mapped to UNIBUS for transmission.
261 	 * Purge any stale data from this BDP, and start the otput.
262 	 */
263 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
264 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);
265 	addr = (struct endevice *)ui->ui_addr;
266 	addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
267 	addr->en_odelay = es->es_delay;
268 	addr->en_owc = -((es->es_olen + 1) >> 1);
269 	addr->en_ostat = EN_IEN|EN_GO;
270 	es->es_oactive = 1;
271 }
272 
273 /*
274  * Ethernet interface transmitter interrupt.
275  * Start another output if more data to send.
276  */
277 enxint(unit)
278 	int unit;
279 {
280 	register struct uba_device *ui = eninfo[unit];
281 	register struct en_softc *es = &en_softc[unit];
282 	register struct endevice *addr = (struct endevice *)ui->ui_addr;
283 
284 	if (es->es_oactive == 0)
285 		return;
286 	if (es->es_mask && (addr->en_ostat&EN_OERROR)) {
287 		es->es_if.if_oerrors++;
288 		endocoll(unit);
289 		return;
290 	}
291 	es->es_if.if_opackets++;
292 	es->es_oactive = 0;
293 	es->es_delay = 0;
294 	es->es_mask = ~0;
295 	if (es->es_ifuba.ifu_xtofree) {
296 		m_freem(es->es_ifuba.ifu_xtofree);
297 		es->es_ifuba.ifu_xtofree = 0;
298 	}
299 	if (es->es_if.if_snd.ifq_head == 0) {
300 		es->es_lastx = 256;		/* putatively illegal */
301 		return;
302 	}
303 	enstart(unit);
304 }
305 
306 /*
307  * Collision on ethernet interface.  Do exponential
308  * backoff, and retransmit.  If have backed off all
309  * the way print warning diagnostic, and drop packet.
310  */
311 encollide(unit)
312 	int unit;
313 {
314 	struct en_softc *es = &en_softc[unit];
315 
316 	es->es_if.if_collisions++;
317 	if (es->es_oactive == 0)
318 		return;
319 	endocoll(unit);
320 }
321 
322 endocoll(unit)
323 	int unit;
324 {
325 	register struct en_softc *es = &en_softc[unit];
326 
327 	/*
328 	 * Es_mask is a 16 bit number with n low zero bits, with
329 	 * n the number of backoffs.  When es_mask is 0 we have
330 	 * backed off 16 times, and give up.
331 	 */
332 	if (es->es_mask == 0) {
333 		printf("en%d: send error\n", unit);
334 		enxint(unit);
335 		return;
336 	}
337 	/*
338 	 * Another backoff.  Restart with delay based on n low bits
339 	 * of the interval timer.
340 	 */
341 	es->es_mask <<= 1;
342 	es->es_delay = mfpr(ICR) &~ es->es_mask;
343 	enstart(unit);
344 }
345 
346 #ifdef notdef
347 struct	sockproto enproto = { AF_ETHERLINK };
348 struct	sockaddr_en endst = { AF_ETHERLINK };
349 struct	sockaddr_en ensrc = { AF_ETHERLINK };
350 #endif
351 /*
352  * Ethernet interface receiver interrupt.
353  * If input error just drop packet.
354  * Otherwise purge input buffered data path and examine
355  * packet to determine type.  If can't determine length
356  * from type, then have to drop packet.  Othewise decapsulate
357  * packet based on type and pass to type specific higher-level
358  * input routine.
359  */
360 enrint(unit)
361 	int unit;
362 {
363 	register struct en_softc *es = &en_softc[unit];
364 	struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
365 	register struct en_header *en;
366     	struct mbuf *m;
367 	int len; short resid;
368 	register struct ifqueue *inq;
369 	int off, s;
370 
371 	es->es_if.if_ipackets++;
372 
373 	/*
374 	 * Purge BDP; drop if input error indicated.
375 	 */
376 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
377 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);
378 	if (addr->en_istat&EN_IERROR) {
379 		es->es_if.if_ierrors++;
380 		goto setup;
381 	}
382 
383 	/*
384 	 * Calculate input data length.
385 	 * Get pointer to ethernet header (in input buffer).
386 	 * Deal with trailer protocol: if type is PUP trailer
387 	 * get true type from first 16-bit word past data.
388 	 * Remember that type was trailer by setting off.
389 	 */
390 	resid = addr->en_iwc;
391 	if (resid)
392 		resid |= 0176000;
393 	len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1;
394 	len -= sizeof (struct en_header);
395 	if (len > ENMRU)
396 		goto setup;			/* sanity */
397 	en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
398 	en->en_type = ntohs(en->en_type);
399 #define	endataaddr(en, off, type)	((type)(((caddr_t)((en)+1)+(off))))
400 	if (en->en_type >= ENTYPE_TRAIL &&
401 	    en->en_type < ENTYPE_TRAIL+ENTYPE_NTRAILER) {
402 		off = (en->en_type - ENTYPE_TRAIL) * 512;
403 		if (off > ENMTU)
404 			goto setup;		/* sanity */
405 		en->en_type = ntohs(*endataaddr(en, off, u_short *));
406 		resid = ntohs(*(endataaddr(en, off+2, u_short *)));
407 		if (off + resid > len)
408 			goto setup;		/* sanity */
409 		len = off + resid;
410 	} else
411 		off = 0;
412 	if (len == 0)
413 		goto setup;
414 #ifdef ENF_SWABIPS
415 	if (es->es_if.if_flags & ENF_SWABIPS && en->en_type == ENTYPE_IP)
416 		enswab((caddr_t)(en + 1), (caddr_t)(en + 1), len);
417 #endif
418 	/*
419 	 * Pull packet off interface.  Off is nonzero if packet
420 	 * has trailing header; if_rubaget will then force this header
421 	 * information to be at the front, but we still have to drop
422 	 * the type and length which are at the front of any trailer data.
423 	 */
424 	m = if_rubaget(&es->es_ifuba, len, off);
425 	if (m == 0)
426 		goto setup;
427 	if (off) {
428 		m->m_off += 2 * sizeof (u_short);
429 		m->m_len -= 2 * sizeof (u_short);
430 	}
431 	switch (en->en_type) {
432 
433 #ifdef INET
434 	case ENTYPE_IP:
435 		schednetisr(NETISR_IP);
436 		inq = &ipintrq;
437 		break;
438 #endif
439 #ifdef PUP
440 	case ENTYPE_PUP:
441 		rpup_input(m);
442 		goto setup;
443 #endif
444 	default:
445 #ifdef notdef
446 		enproto.sp_protocol = en->en_type;
447 		endst.sen_host = en->en_dhost;
448 		endst.sen_net = ensrc.sen_net = es->es_if.if_net;
449 		ensrc.sen_host = en->en_shost;
450 		raw_input(m, &enproto,
451 		    (struct sockaddr *)&ensrc, (struct sockaddr *)&endst);
452 #else
453 		m_freem(m);
454 #endif
455 		goto setup;
456 	}
457 
458 	s = splimp();
459 	if (IF_QFULL(inq)) {
460 		IF_DROP(inq);
461 		m_freem(m);
462 	} else
463 		IF_ENQUEUE(inq, m);
464 	splx(s);
465 
466 setup:
467 	/*
468 	 * Reset for next packet.
469 	 */
470 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
471 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
472 	addr->en_istat = EN_IEN|EN_GO;
473 }
474 
475 /*
476  * Ethernet output routine.
477  * Encapsulate a packet of type family for the local net.
478  * Use trailer local net encapsulation if enough data in first
479  * packet leaves a multiple of 512 bytes of data in remainder.
480  */
481 enoutput(ifp, m0, dst)
482 	struct ifnet *ifp;
483 	struct mbuf *m0;
484 	struct sockaddr *dst;
485 {
486 	int type, dest, s, error;
487 	register struct mbuf *m = m0;
488 	register struct en_header *en;
489 	register int off;
490 
491 	switch (dst->sa_family) {
492 
493 #ifdef INET
494 	case AF_INET:
495 		{
496 		struct in_addr in;
497 
498 		in = ((struct sockaddr_in *)dst)->sin_addr;
499 		if (in_broadcast(in))
500 			dest = EN_BROADCAST;
501 		else
502 			dest = in_lnaof(in);
503 		}
504 		if (dest >= 0x100) {
505 			error = EPERM;		/* ??? */
506 			goto bad;
507 		}
508 		off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
509 		/* need per host negotiation */
510 		if ((ifp->if_flags & IFF_NOTRAILERS) == 0)
511 		if (off > 0 && (off & 0x1ff) == 0 &&
512 		    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {
513 			type = ENTYPE_TRAIL + (off>>9);
514 			m->m_off -= 2 * sizeof (u_short);
515 			m->m_len += 2 * sizeof (u_short);
516 			*mtod(m, u_short *) = htons((u_short)ENTYPE_IP);
517 			*(mtod(m, u_short *) + 1) = ntohs((u_short)m->m_len);
518 			goto gottrailertype;
519 		}
520 		type = ENTYPE_IP;
521 		off = 0;
522 		goto gottype;
523 #endif
524 #ifdef PUP
525 	case AF_PUP:
526 		dest = ((struct sockaddr_pup *)dst)->spup_host;
527 		type = ENTYPE_PUP;
528 		off = 0;
529 		goto gottype;
530 #endif
531 
532 #ifdef notdef
533 	case AF_ETHERLINK:
534 		goto gotheader;
535 #endif
536 
537 	default:
538 		printf("en%d: can't handle af%d\n", ifp->if_unit,
539 			dst->sa_family);
540 		error = EAFNOSUPPORT;
541 		goto bad;
542 	}
543 
544 gottrailertype:
545 	/*
546 	 * Packet to be sent as trailer: move first packet
547 	 * (control information) to end of chain.
548 	 */
549 	while (m->m_next)
550 		m = m->m_next;
551 	m->m_next = m0;
552 	m = m0->m_next;
553 	m0->m_next = 0;
554 	m0 = m;
555 
556 gottype:
557 	/*
558 	 * Add local net header.  If no space in first mbuf,
559 	 * allocate another.
560 	 */
561 	if (m->m_off > MMAXOFF ||
562 	    MMINOFF + sizeof (struct en_header) > m->m_off) {
563 		MGET(m, M_DONTWAIT, MT_HEADER);
564 		if (m == 0) {
565 			error = ENOBUFS;
566 			goto bad;
567 		}
568 		m->m_next = m0;
569 		m->m_off = MMINOFF;
570 		m->m_len = sizeof (struct en_header);
571 	} else {
572 		m->m_off -= sizeof (struct en_header);
573 		m->m_len += sizeof (struct en_header);
574 	}
575 	en = mtod(m, struct en_header *);
576 	/* add en_shost later */
577 	en->en_dhost = dest;
578 	en->en_type = htons((u_short)type);
579 
580 gotheader:
581 	/*
582 	 * Queue message on interface, and start output if interface
583 	 * not yet active.
584 	 */
585 	s = splimp();
586 	if (IF_QFULL(&ifp->if_snd)) {
587 		IF_DROP(&ifp->if_snd);
588 		error = ENOBUFS;
589 		goto qfull;
590 	}
591 	IF_ENQUEUE(&ifp->if_snd, m);
592 	if (en_softc[ifp->if_unit].es_oactive == 0)
593 		enstart(ifp->if_unit);
594 	splx(s);
595 	return (0);
596 qfull:
597 	m0 = m;
598 	splx(s);
599 bad:
600 	m_freem(m0);
601 	return (error);
602 }
603 
604 /*
605  * Process an ioctl request.
606  */
607 enioctl(ifp, cmd, data)
608 	register struct ifnet *ifp;
609 	int cmd;
610 	caddr_t data;
611 {
612 	register struct en_softc *es = ((struct en_softc *)ifp);
613 	struct ifaddr *ifa = (struct ifaddr *) data;
614 	int s = splimp(), error = 0;
615 	struct endevice *enaddr;
616 
617 	switch (cmd) {
618 
619 	case SIOCSIFADDR:
620 		enaddr = (struct endevice *)eninfo[ifp->if_unit]->ui_addr;
621 		es->es_host = (~enaddr->en_addr) & 0xff;
622 		/*
623 		 * Attempt to check agreement of protocol address
624 		 * and board address.
625 		 */
626 		switch (ifa->ifa_addr.sa_family) {
627 		case AF_INET:
628 			if (in_lnaof(IA_SIN(ifa)->sin_addr) != es->es_host)
629 				return (EADDRNOTAVAIL);
630 			break;
631 		}
632 		ifp->if_flags |= IFF_UP;
633 		if ((ifp->if_flags & IFF_RUNNING) == 0)
634 			eninit(ifp->if_unit);
635 		break;
636 
637 	default:
638 		error = EINVAL;
639 	}
640 	splx(s);
641 	return (error);
642 }
643 
644 #ifdef ENF_SWABIPS
645 /*
646  * Swab bytes
647  * Jeffrey Mogul, Stanford
648  */
649 enswab(from, to, n)
650 	register unsigned char *from, *to;
651 	register int n;
652 {
653 	register unsigned long temp;
654 
655 	if ((n <= 0) || (n > 0xFFFF)) {
656 		printf("enswab: bad len %d\n", n);
657 		return;
658 	}
659 
660 	n >>= 1; n++;
661 #define	STEP	{temp = *from++;*to++ = *from++;*to++ = temp;}
662 	/* round to multiple of 8 */
663 	while ((--n) & 07)
664 		STEP;
665 	n >>= 3;
666 	while (--n >= 0) {
667 		STEP; STEP; STEP; STEP;
668 		STEP; STEP; STEP; STEP;
669 	}
670 }
671 #endif
672