xref: /csrg-svn/sys/vax/if/if_en.c (revision 23290)
1 /*
2  * Copyright (c) 1982 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)if_en.c	6.8 (Berkeley) 06/08/85
7  */
8 
9 #include "en.h"
10 
11 /*
12  * Xerox prototype (3 Mb) Ethernet interface driver.
13  */
14 #include "../machine/pte.h"
15 
16 #include "param.h"
17 #include "systm.h"
18 #include "mbuf.h"
19 #include "buf.h"
20 #include "protosw.h"
21 #include "socket.h"
22 #include "vmmac.h"
23 #include "errno.h"
24 #include "ioctl.h"
25 
26 #include "../net/if.h"
27 #include "../net/netisr.h"
28 #include "../net/route.h"
29 #include "../netinet/in.h"
30 #include "../netinet/in_systm.h"
31 #include "../netinet/in_var.h"
32 #include "../netinet/ip.h"
33 #include "../netinet/ip_var.h"
34 #ifdef PUP
35 #include "../netpup/pup.h"
36 #include "../netpup/ether.h"
37 #endif
38 
39 #include "../vax/cpu.h"
40 #include "../vax/mtpr.h"
41 #include "if_en.h"
42 #include "if_enreg.h"
43 #include "if_uba.h"
44 #include "../vaxuba/ubareg.h"
45 #include "../vaxuba/ubavar.h"
46 
47 #define	ENMTU	(1024+512)
48 #define	ENMRU	(1024+512+16)		/* 16 is enough to receive trailer */
49 
50 int	enprobe(), enattach(), enrint(), enxint(), encollide();
51 struct	uba_device *eninfo[NEN];
52 u_short enstd[] = { 0 };
53 struct	uba_driver endriver =
54 	{ enprobe, 0, enattach, 0, enstd, "en", eninfo };
55 #define	ENUNIT(x)	minor(x)
56 
57 int	eninit(),enoutput(),enreset(),enioctl();
58 
59 #ifdef notdef
60 /*
61  * If you need to byte swap IP's in the system, define
62  * this and do a SIOCSIFFLAGS at boot time.
63  */
64 #define	ENF_SWABIPS	0x1000
65 #endif
66 
67 /*
68  * Ethernet software status per interface.
69  *
70  * Each interface is referenced by a network interface structure,
71  * es_if, which the routing code uses to locate the interface.
72  * This structure contains the output queue for the interface, its address, ...
73  * We also have, for each interface, a UBA interface structure, which
74  * contains information about the UNIBUS resources held by the interface:
75  * map registers, buffered data paths, etc.  Information is cached in this
76  * structure for use by the if_uba.c routines in running the interface
77  * efficiently.
78  */
79 struct	en_softc {
80 	struct	ifnet es_if;		/* network-visible interface */
81 	struct	ifuba es_ifuba;		/* UNIBUS resources */
82 	short	es_host;		/* hardware host number */
83 	short	es_delay;		/* current output delay */
84 	short	es_mask;		/* mask for current output delay */
85 	short	es_lastx;		/* host last transmitted to */
86 	short	es_oactive;		/* is output active? */
87 	short	es_olen;		/* length of last output */
88 } en_softc[NEN];
89 
90 /*
91  * Do output DMA to determine interface presence and
92  * interrupt vector.  DMA is too short to disturb other hosts.
93  */
94 enprobe(reg)
95 	caddr_t reg;
96 {
97 	register int br, cvec;		/* r11, r10 value-result */
98 	register struct endevice *addr = (struct endevice *)reg;
99 
100 #ifdef lint
101 	br = 0; cvec = br; br = cvec;
102 	enrint(0); enxint(0); encollide(0);
103 #endif
104 	addr->en_istat = 0;
105 	addr->en_owc = -1;
106 	addr->en_oba = 0;
107 	addr->en_ostat = EN_IEN|EN_GO;
108 	DELAY(100000);
109 	addr->en_ostat = 0;
110 	return (1);
111 }
112 
113 /*
114  * Interface exists: make available by filling in network interface
115  * record.  System will initialize the interface when it is ready
116  * to accept packets.
117  */
118 enattach(ui)
119 	struct uba_device *ui;
120 {
121 	register struct en_softc *es = &en_softc[ui->ui_unit];
122 
123 	es->es_if.if_unit = ui->ui_unit;
124 	es->es_if.if_name = "en";
125 	es->es_if.if_mtu = ENMTU;
126 	es->es_if.if_flags = IFF_BROADCAST;
127 	es->es_if.if_init = eninit;
128 	es->es_if.if_output = enoutput;
129 	es->es_if.if_ioctl = enioctl;
130 	es->es_if.if_reset = enreset;
131 	es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT;
132 #if defined(VAX750)
133 	/* don't chew up 750 bdp's */
134 	if (cpu == VAX_750 && ui->ui_unit > 0)
135 		es->es_ifuba.ifu_flags &= ~UBA_NEEDBDP;
136 #endif
137 	if_attach(&es->es_if);
138 }
139 
140 /*
141  * Reset of interface after UNIBUS reset.
142  * If interface is on specified uba, reset its state.
143  */
144 enreset(unit, uban)
145 	int unit, uban;
146 {
147 	register struct uba_device *ui;
148 
149 	if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
150 	    ui->ui_ubanum != uban)
151 		return;
152 	printf(" en%d", unit);
153 	eninit(unit);
154 }
155 
156 /*
157  * Initialization of interface; clear recorded pending
158  * operations, and reinitialize UNIBUS usage.
159  */
160 eninit(unit)
161 	int unit;
162 {
163 	register struct en_softc *es = &en_softc[unit];
164 	register struct uba_device *ui = eninfo[unit];
165 	register struct endevice *addr;
166 	int s;
167 
168 	if (es->es_if.if_addrlist == (struct ifaddr *)0)
169 		return;
170 	if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,
171 	    sizeof (struct en_header), (int)btoc(ENMRU)) == 0) {
172 		printf("en%d: can't initialize\n", unit);
173 		es->es_if.if_flags &= ~IFF_UP;
174 		return;
175 	}
176 	addr = (struct endevice *)ui->ui_addr;
177 	addr->en_istat = addr->en_ostat = 0;
178 
179 	/*
180 	 * Hang a receive and start any
181 	 * pending writes by faking a transmit complete.
182 	 */
183 	s = splimp();
184 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
185 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
186 	addr->en_istat = EN_IEN|EN_GO;
187 	es->es_oactive = 1;
188 	es->es_if.if_flags |= IFF_RUNNING;
189 	enxint(unit);
190 	splx(s);
191 }
192 
193 int	enalldelay = 0;
194 int	enlastdel = 50;
195 int	enlastmask = (~0) << 5;
196 
197 /*
198  * Start or restart output on interface.
199  * If interface is already active, then this is a retransmit
200  * after a collision, and just restuff registers and delay.
201  * If interface is not already active, get another datagram
202  * to send off of the interface queue, and map it to the interface
203  * before starting the output.
204  */
205 enstart(dev)
206 	dev_t dev;
207 {
208         int unit = ENUNIT(dev);
209 	struct uba_device *ui = eninfo[unit];
210 	register struct en_softc *es = &en_softc[unit];
211 	register struct endevice *addr;
212 	register struct en_header *en;
213 	struct mbuf *m;
214 	int dest;
215 
216 	if (es->es_oactive)
217 		goto restart;
218 
219 	/*
220 	 * Not already active: dequeue another request
221 	 * and map it to the UNIBUS.  If no more requests,
222 	 * just return.
223 	 */
224 	IF_DEQUEUE(&es->es_if.if_snd, m);
225 	if (m == 0) {
226 		es->es_oactive = 0;
227 		return;
228 	}
229 	en = mtod(m, struct en_header *);
230 	dest = en->en_dhost;
231 	en->en_shost = es->es_host;
232 	es->es_olen = if_wubaput(&es->es_ifuba, m);
233 #ifdef ENF_SWABIPS
234 	/*
235 	 * The Xerox interface does word at a time DMA, so
236 	 * someone must do byte swapping of user data if high
237 	 * and low ender machines are to communicate.  It doesn't
238 	 * belong here, but certain people depend on it, so...
239 	 *
240 	 * Should swab everybody, but this is a kludge anyway.
241 	 */
242 	if (es->es_if.if_flags & ENF_SWABIPS) {
243 		en = (struct en_header *)es->es_ifuba.ifu_w.ifrw_addr;
244 		if (en->en_type == ENTYPE_IP)
245 			enswab((caddr_t)(en + 1), (caddr_t)(en + 1),
246 			    es->es_olen - sizeof (struct en_header) + 1);
247 	}
248 #endif
249 
250 	/*
251 	 * Ethernet cannot take back-to-back packets (no
252 	 * buffering in interface.  To help avoid overrunning
253 	 * receivers, enforce a small delay (about 1ms) in interface:
254 	 *	* between all packets when enalldelay
255 	 *	* whenever last packet was broadcast
256 	 *	* whenever this packet is to same host as last packet
257 	 */
258 	if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) {
259 		es->es_delay = enlastdel;
260 		es->es_mask = enlastmask;
261 	}
262 	es->es_lastx = dest;
263 
264 restart:
265 	/*
266 	 * Have request mapped to UNIBUS for transmission.
267 	 * Purge any stale data from this BDP, and start the otput.
268 	 */
269 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
270 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);
271 	addr = (struct endevice *)ui->ui_addr;
272 	addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
273 	addr->en_odelay = es->es_delay;
274 	addr->en_owc = -((es->es_olen + 1) >> 1);
275 	addr->en_ostat = EN_IEN|EN_GO;
276 	es->es_oactive = 1;
277 }
278 
279 /*
280  * Ethernet interface transmitter interrupt.
281  * Start another output if more data to send.
282  */
283 enxint(unit)
284 	int unit;
285 {
286 	register struct uba_device *ui = eninfo[unit];
287 	register struct en_softc *es = &en_softc[unit];
288 	register struct endevice *addr = (struct endevice *)ui->ui_addr;
289 
290 	if (es->es_oactive == 0)
291 		return;
292 	if (es->es_mask && (addr->en_ostat&EN_OERROR)) {
293 		es->es_if.if_oerrors++;
294 		endocoll(unit);
295 		return;
296 	}
297 	es->es_if.if_opackets++;
298 	es->es_oactive = 0;
299 	es->es_delay = 0;
300 	es->es_mask = ~0;
301 	if (es->es_ifuba.ifu_xtofree) {
302 		m_freem(es->es_ifuba.ifu_xtofree);
303 		es->es_ifuba.ifu_xtofree = 0;
304 	}
305 	if (es->es_if.if_snd.ifq_head == 0) {
306 		es->es_lastx = 256;		/* putatively illegal */
307 		return;
308 	}
309 	enstart(unit);
310 }
311 
312 /*
313  * Collision on ethernet interface.  Do exponential
314  * backoff, and retransmit.  If have backed off all
315  * the way print warning diagnostic, and drop packet.
316  */
317 encollide(unit)
318 	int unit;
319 {
320 	struct en_softc *es = &en_softc[unit];
321 
322 	es->es_if.if_collisions++;
323 	if (es->es_oactive == 0)
324 		return;
325 	endocoll(unit);
326 }
327 
328 endocoll(unit)
329 	int unit;
330 {
331 	register struct en_softc *es = &en_softc[unit];
332 
333 	/*
334 	 * Es_mask is a 16 bit number with n low zero bits, with
335 	 * n the number of backoffs.  When es_mask is 0 we have
336 	 * backed off 16 times, and give up.
337 	 */
338 	if (es->es_mask == 0) {
339 		printf("en%d: send error\n", unit);
340 		enxint(unit);
341 		return;
342 	}
343 	/*
344 	 * Another backoff.  Restart with delay based on n low bits
345 	 * of the interval timer.
346 	 */
347 	es->es_mask <<= 1;
348 	es->es_delay = mfpr(ICR) &~ es->es_mask;
349 	enstart(unit);
350 }
351 
352 #ifdef notdef
353 struct	sockproto enproto = { AF_ETHERLINK };
354 struct	sockaddr_en endst = { AF_ETHERLINK };
355 struct	sockaddr_en ensrc = { AF_ETHERLINK };
356 #endif
357 /*
358  * Ethernet interface receiver interrupt.
359  * If input error just drop packet.
360  * Otherwise purge input buffered data path and examine
361  * packet to determine type.  If can't determine length
362  * from type, then have to drop packet.  Othewise decapsulate
363  * packet based on type and pass to type specific higher-level
364  * input routine.
365  */
366 enrint(unit)
367 	int unit;
368 {
369 	register struct en_softc *es = &en_softc[unit];
370 	struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
371 	register struct en_header *en;
372     	struct mbuf *m;
373 	int len; short resid;
374 	register struct ifqueue *inq;
375 	int off, s;
376 
377 	es->es_if.if_ipackets++;
378 
379 	/*
380 	 * Purge BDP; drop if input error indicated.
381 	 */
382 	if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
383 		UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);
384 	if (addr->en_istat&EN_IERROR) {
385 		es->es_if.if_ierrors++;
386 		goto setup;
387 	}
388 
389 	/*
390 	 * Calculate input data length.
391 	 * Get pointer to ethernet header (in input buffer).
392 	 * Deal with trailer protocol: if type is PUP trailer
393 	 * get true type from first 16-bit word past data.
394 	 * Remember that type was trailer by setting off.
395 	 */
396 	resid = addr->en_iwc;
397 	if (resid)
398 		resid |= 0176000;
399 	len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1;
400 	len -= sizeof (struct en_header);
401 	if (len > ENMRU)
402 		goto setup;			/* sanity */
403 	en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
404 	en->en_type = ntohs(en->en_type);
405 #define	endataaddr(en, off, type)	((type)(((caddr_t)((en)+1)+(off))))
406 	if (en->en_type >= ENTYPE_TRAIL &&
407 	    en->en_type < ENTYPE_TRAIL+ENTYPE_NTRAILER) {
408 		off = (en->en_type - ENTYPE_TRAIL) * 512;
409 		if (off > ENMTU)
410 			goto setup;		/* sanity */
411 		en->en_type = ntohs(*endataaddr(en, off, u_short *));
412 		resid = ntohs(*(endataaddr(en, off+2, u_short *)));
413 		if (off + resid > len)
414 			goto setup;		/* sanity */
415 		len = off + resid;
416 	} else
417 		off = 0;
418 	if (len == 0)
419 		goto setup;
420 #ifdef ENF_SWABIPS
421 	if (es->es_if.if_flags & ENF_SWABIPS && en->en_type == ENTYPE_IP)
422 		enswab((caddr_t)(en + 1), (caddr_t)(en + 1), len);
423 #endif
424 	/*
425 	 * Pull packet off interface.  Off is nonzero if packet
426 	 * has trailing header; if_rubaget will then force this header
427 	 * information to be at the front, but we still have to drop
428 	 * the type and length which are at the front of any trailer data.
429 	 */
430 	m = if_rubaget(&es->es_ifuba, len, off);
431 	if (m == 0)
432 		goto setup;
433 	if (off) {
434 		m->m_off += 2 * sizeof (u_short);
435 		m->m_len -= 2 * sizeof (u_short);
436 	}
437 	switch (en->en_type) {
438 
439 #ifdef INET
440 	case ENTYPE_IP:
441 		schednetisr(NETISR_IP);
442 		inq = &ipintrq;
443 		break;
444 #endif
445 #ifdef PUP
446 	case ENTYPE_PUP:
447 		rpup_input(m);
448 		goto setup;
449 #endif
450 	default:
451 #ifdef notdef
452 		enproto.sp_protocol = en->en_type;
453 		endst.sen_host = en->en_dhost;
454 		endst.sen_net = ensrc.sen_net = es->es_if.if_net;
455 		ensrc.sen_host = en->en_shost;
456 		raw_input(m, &enproto,
457 		    (struct sockaddr *)&ensrc, (struct sockaddr *)&endst);
458 #else
459 		m_freem(m);
460 #endif
461 		goto setup;
462 	}
463 
464 	s = splimp();
465 	if (IF_QFULL(inq)) {
466 		IF_DROP(inq);
467 		m_freem(m);
468 	} else
469 		IF_ENQUEUE(inq, m);
470 	splx(s);
471 
472 setup:
473 	/*
474 	 * Reset for next packet.
475 	 */
476 	addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
477 	addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;
478 	addr->en_istat = EN_IEN|EN_GO;
479 }
480 
481 /*
482  * Ethernet output routine.
483  * Encapsulate a packet of type family for the local net.
484  * Use trailer local net encapsulation if enough data in first
485  * packet leaves a multiple of 512 bytes of data in remainder.
486  */
487 enoutput(ifp, m0, dst)
488 	struct ifnet *ifp;
489 	struct mbuf *m0;
490 	struct sockaddr *dst;
491 {
492 	int type, dest, s, error;
493 	register struct mbuf *m = m0;
494 	register struct en_header *en;
495 	register int off;
496 
497 	switch (dst->sa_family) {
498 
499 #ifdef INET
500 	case AF_INET:
501 		{
502 		struct in_addr in;
503 
504 		in = ((struct sockaddr_in *)dst)->sin_addr;
505 		if (in_broadcast(in))
506 			dest = EN_BROADCAST;
507 		else
508 			dest = in_lnaof(in);
509 		}
510 		if (dest >= 0x100) {
511 			error = EPERM;		/* ??? */
512 			goto bad;
513 		}
514 		off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
515 		/* need per host negotiation */
516 		if ((ifp->if_flags & IFF_NOTRAILERS) == 0)
517 		if (off > 0 && (off & 0x1ff) == 0 &&
518 		    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {
519 			type = ENTYPE_TRAIL + (off>>9);
520 			m->m_off -= 2 * sizeof (u_short);
521 			m->m_len += 2 * sizeof (u_short);
522 			*mtod(m, u_short *) = htons((u_short)ENTYPE_IP);
523 			*(mtod(m, u_short *) + 1) = ntohs((u_short)m->m_len);
524 			goto gottrailertype;
525 		}
526 		type = ENTYPE_IP;
527 		off = 0;
528 		goto gottype;
529 #endif
530 #ifdef PUP
531 	case AF_PUP:
532 		dest = ((struct sockaddr_pup *)dst)->spup_host;
533 		type = ENTYPE_PUP;
534 		off = 0;
535 		goto gottype;
536 #endif
537 
538 #ifdef notdef
539 	case AF_ETHERLINK:
540 		goto gotheader;
541 #endif
542 
543 	default:
544 		printf("en%d: can't handle af%d\n", ifp->if_unit,
545 			dst->sa_family);
546 		error = EAFNOSUPPORT;
547 		goto bad;
548 	}
549 
550 gottrailertype:
551 	/*
552 	 * Packet to be sent as trailer: move first packet
553 	 * (control information) to end of chain.
554 	 */
555 	while (m->m_next)
556 		m = m->m_next;
557 	m->m_next = m0;
558 	m = m0->m_next;
559 	m0->m_next = 0;
560 	m0 = m;
561 
562 gottype:
563 	/*
564 	 * Add local net header.  If no space in first mbuf,
565 	 * allocate another.
566 	 */
567 	if (m->m_off > MMAXOFF ||
568 	    MMINOFF + sizeof (struct en_header) > m->m_off) {
569 		MGET(m, M_DONTWAIT, MT_HEADER);
570 		if (m == 0) {
571 			error = ENOBUFS;
572 			goto bad;
573 		}
574 		m->m_next = m0;
575 		m->m_off = MMINOFF;
576 		m->m_len = sizeof (struct en_header);
577 	} else {
578 		m->m_off -= sizeof (struct en_header);
579 		m->m_len += sizeof (struct en_header);
580 	}
581 	en = mtod(m, struct en_header *);
582 	/* add en_shost later */
583 	en->en_dhost = dest;
584 	en->en_type = htons((u_short)type);
585 
586 gotheader:
587 	/*
588 	 * Queue message on interface, and start output if interface
589 	 * not yet active.
590 	 */
591 	s = splimp();
592 	if (IF_QFULL(&ifp->if_snd)) {
593 		IF_DROP(&ifp->if_snd);
594 		error = ENOBUFS;
595 		goto qfull;
596 	}
597 	IF_ENQUEUE(&ifp->if_snd, m);
598 	if (en_softc[ifp->if_unit].es_oactive == 0)
599 		enstart(ifp->if_unit);
600 	splx(s);
601 	return (0);
602 qfull:
603 	m0 = m;
604 	splx(s);
605 bad:
606 	m_freem(m0);
607 	return (error);
608 }
609 
610 /*
611  * Process an ioctl request.
612  */
613 enioctl(ifp, cmd, data)
614 	register struct ifnet *ifp;
615 	int cmd;
616 	caddr_t data;
617 {
618 	register struct en_softc *es = ((struct en_softc *)ifp);
619 	struct ifaddr *ifa = (struct ifaddr *) data;
620 	int s = splimp(), error = 0;
621 	struct endevice *enaddr;
622 
623 	switch (cmd) {
624 
625 	case SIOCSIFADDR:
626 		enaddr = (struct endevice *)eninfo[ifp->if_unit]->ui_addr;
627 		es->es_host = (~enaddr->en_addr) & 0xff;
628 		/*
629 		 * Attempt to check agreement of protocol address
630 		 * and board address.
631 		 */
632 		switch (ifa->ifa_addr.sa_family) {
633 		case AF_INET:
634 			if (in_lnaof(IA_SIN(ifa)->sin_addr) != es->es_host)
635 				return (EADDRNOTAVAIL);
636 			break;
637 		}
638 		ifp->if_flags |= IFF_UP;
639 		if ((ifp->if_flags & IFF_RUNNING) == 0)
640 			eninit(ifp->if_unit);
641 		break;
642 
643 	default:
644 		error = EINVAL;
645 	}
646 	splx(s);
647 	return (error);
648 }
649 
650 #ifdef ENF_SWABIPS
651 /*
652  * Swab bytes
653  * Jeffrey Mogul, Stanford
654  */
655 enswab(from, to, n)
656 	register unsigned char *from, *to;
657 	register int n;
658 {
659 	register unsigned long temp;
660 
661 	if ((n <= 0) || (n > 0xFFFF)) {
662 		printf("enswab: bad len %d\n", n);
663 		return;
664 	}
665 
666 	n >>= 1; n++;
667 #define	STEP	{temp = *from++;*to++ = *from++;*to++ = temp;}
668 	/* round to multiple of 8 */
669 	while ((--n) & 07)
670 		STEP;
671 	n >>= 3;
672 	while (--n >= 0) {
673 		STEP; STEP; STEP; STEP;
674 		STEP; STEP; STEP; STEP;
675 	}
676 }
677 #endif
678