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if_dmc.c revision 1.17
      1 /*	$NetBSD: if_dmc.c,v 1.17 2008/11/07 00:20:12 dyoung Exp $	*/
      2 /*
      3  * Copyright (c) 1982, 1986 Regents of the University of California.
      4  * 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. Neither the name of the University nor the names of its contributors
     15  *    may be used to endorse or promote products derived from this software
     16  *    without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     28  * SUCH DAMAGE.
     29  *
     30  *	@(#)if_dmc.c	7.10 (Berkeley) 12/16/90
     31  */
     32 
     33 /*
     34  * DMC11 device driver, internet version
     35  *
     36  *	Bill Nesheim
     37  *	Cornell University
     38  *
     39  *	Lou Salkind
     40  *	New York University
     41  */
     42 
     43 #include <sys/cdefs.h>
     44 __KERNEL_RCSID(0, "$NetBSD: if_dmc.c,v 1.17 2008/11/07 00:20:12 dyoung Exp $");
     45 
     46 #undef DMCDEBUG	/* for base table dump on fatal error */
     47 
     48 #include "opt_inet.h"
     49 
     50 #include <sys/param.h>
     51 #include <sys/systm.h>
     52 #include <sys/mbuf.h>
     53 #include <sys/ioctl.h>
     54 #include <sys/socket.h>
     55 #include <sys/syslog.h>
     56 #include <sys/device.h>
     57 
     58 #include <net/if.h>
     59 #include <net/netisr.h>
     60 
     61 #ifdef	INET
     62 #include <netinet/in.h>
     63 #include <netinet/in_var.h>
     64 #endif
     65 
     66 #include <sys/bus.h>
     67 
     68 #include <dev/qbus/ubareg.h>
     69 #include <dev/qbus/ubavar.h>
     70 #include <dev/qbus/if_uba.h>
     71 
     72 #include <dev/qbus/if_dmcreg.h>
     73 
     74 
     75 /*
     76  * output timeout value, sec.; should depend on line speed.
     77  */
     78 static int dmc_timeout = 20;
     79 
     80 #define NRCV 7
     81 #define NXMT 3
     82 #define NCMDS	(NRCV+NXMT+4)	/* size of command queue */
     83 
     84 #define DMC_WBYTE(csr, val) \
     85 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, csr, val)
     86 #define DMC_WWORD(csr, val) \
     87 	bus_space_write_2(sc->sc_iot, sc->sc_ioh, csr, val)
     88 #define DMC_RBYTE(csr) \
     89 	bus_space_read_1(sc->sc_iot, sc->sc_ioh, csr)
     90 #define DMC_RWORD(csr) \
     91 	bus_space_read_2(sc->sc_iot, sc->sc_ioh, csr)
     92 
     93 
     94 #ifdef DMCDEBUG
     95 #define printd if(dmcdebug)printf
     96 int dmcdebug = 0;
     97 #endif
     98 
     99 /* error reporting intervals */
    100 #define DMC_RPNBFS	50
    101 #define DMC_RPDSC	1
    102 #define DMC_RPTMO	10
    103 #define DMC_RPDCK	10
    104 
    105 struct  dmc_command {
    106 	char	qp_cmd;		/* command */
    107 	short	qp_ubaddr;	/* buffer address */
    108 	short	qp_cc;		/* character count || XMEM */
    109 	struct	dmc_command *qp_next;	/* next command on queue */
    110 };
    111 
    112 struct dmcbufs {
    113 	int	ubinfo;		/* from uballoc */
    114 	short	cc;		/* buffer size */
    115 	short	flags;		/* access control */
    116 };
    117 #define	DBUF_OURS	0	/* buffer is available */
    118 #define	DBUF_DMCS	1	/* buffer claimed by somebody */
    119 #define	DBUF_XMIT	4	/* transmit buffer */
    120 #define	DBUF_RCV	8	/* receive buffer */
    121 
    122 
    123 /*
    124  * DMC software status per interface.
    125  *
    126  * Each interface is referenced by a network interface structure,
    127  * sc_if, which the routing code uses to locate the interface.
    128  * This structure contains the output queue for the interface, its address, ...
    129  * We also have, for each interface, a  set of 7 UBA interface structures
    130  * for each, which
    131  * contain information about the UNIBUS resources held by the interface:
    132  * map registers, buffered data paths, etc.  Information is cached in this
    133  * structure for use by the if_uba.c routines in running the interface
    134  * efficiently.
    135  */
    136 struct dmc_softc {
    137 	struct	device sc_dev;		/* Configuration common part */
    138 	struct	ifnet sc_if;		/* network-visible interface */
    139 	short	sc_oused;		/* output buffers currently in use */
    140 	short	sc_iused;		/* input buffers given to DMC */
    141 	short	sc_flag;		/* flags */
    142 	struct	ubinfo sc_ui;		/* UBA mapping info for base table */
    143 	int	sc_errors[4];		/* non-fatal error counters */
    144 	bus_space_tag_t sc_iot;
    145 	bus_addr_t sc_ioh;
    146 	bus_dma_tag_t sc_dmat;
    147 	struct	evcnt sc_rintrcnt;	/* Interrupt counting */
    148 	struct	evcnt sc_tintrcnt;	/* Interrupt counting */
    149 #define sc_datck sc_errors[0]
    150 #define sc_timeo sc_errors[1]
    151 #define sc_nobuf sc_errors[2]
    152 #define sc_disc  sc_errors[3]
    153 	struct	dmcbufs sc_rbufs[NRCV];	/* receive buffer info */
    154 	struct	dmcbufs sc_xbufs[NXMT];	/* transmit buffer info */
    155 	struct	ifubinfo sc_ifuba;	/* UNIBUS resources */
    156 	struct	ifrw sc_ifr[NRCV];	/* UNIBUS receive buffer maps */
    157 	struct	ifxmt sc_ifw[NXMT];	/* UNIBUS receive buffer maps */
    158 	/* command queue stuff */
    159 	struct	dmc_command sc_cmdbuf[NCMDS];
    160 	struct	dmc_command *sc_qhead;	/* head of command queue */
    161 	struct	dmc_command *sc_qtail;	/* tail of command queue */
    162 	struct	dmc_command *sc_qactive;	/* command in progress */
    163 	struct	dmc_command *sc_qfreeh;	/* head of list of free cmd buffers */
    164 	struct	dmc_command *sc_qfreet;	/* tail of list of free cmd buffers */
    165 	/* end command queue stuff */
    166 	struct dmc_base {
    167 		short	d_base[128];		/* DMC base table */
    168 	} dmc_base;
    169 };
    170 
    171 static  int dmcmatch(struct device *, struct cfdata *, void *);
    172 static  void dmcattach(struct device *, struct device *, void *);
    173 static  int dmcinit(struct ifnet *);
    174 static  void dmcrint(void *);
    175 static  void dmcxint(void *);
    176 static  void dmcdown(struct dmc_softc *sc);
    177 static  void dmcrestart(struct dmc_softc *);
    178 static  void dmcload(struct dmc_softc *, int, u_short, u_short);
    179 static  void dmcstart(struct ifnet *);
    180 static  void dmctimeout(struct ifnet *);
    181 static  int dmcioctl(struct ifnet *, u_long, void *);
    182 static  int dmcoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
    183 	struct rtentry *);
    184 static  void dmcreset(struct device *);
    185 
    186 CFATTACH_DECL(dmc, sizeof(struct dmc_softc),
    187     dmcmatch, dmcattach, NULL, NULL);
    188 
    189 /* flags */
    190 #define DMC_RUNNING	0x01		/* device initialized */
    191 #define DMC_BMAPPED	0x02		/* base table mapped */
    192 #define DMC_RESTART	0x04		/* software restart in progress */
    193 #define DMC_ONLINE	0x08		/* device running (had a RDYO) */
    194 
    195 
    196 /* queue manipulation macros */
    197 #define	QUEUE_AT_HEAD(qp, head, tail) \
    198 	(qp)->qp_next = (head); \
    199 	(head) = (qp); \
    200 	if ((tail) == (struct dmc_command *) 0) \
    201 		(tail) = (head)
    202 
    203 #define QUEUE_AT_TAIL(qp, head, tail) \
    204 	if ((tail)) \
    205 		(tail)->qp_next = (qp); \
    206 	else \
    207 		(head) = (qp); \
    208 	(qp)->qp_next = (struct dmc_command *) 0; \
    209 	(tail) = (qp)
    210 
    211 #define DEQUEUE(head, tail) \
    212 	(head) = (head)->qp_next;\
    213 	if ((head) == (struct dmc_command *) 0)\
    214 		(tail) = (head)
    215 
    216 int
    217 dmcmatch(struct device *parent, struct cfdata *cf, void *aux)
    218 {
    219 	struct uba_attach_args *ua = aux;
    220 	struct dmc_softc ssc;
    221 	struct dmc_softc *sc = &ssc;
    222 	int i;
    223 
    224 	sc->sc_iot = ua->ua_iot;
    225 	sc->sc_ioh = ua->ua_ioh;
    226 
    227 	DMC_WBYTE(DMC_BSEL1, DMC_MCLR);
    228 	for (i = 100000; i && (DMC_RBYTE(DMC_BSEL1) & DMC_RUN) == 0; i--)
    229 		;
    230 	if ((DMC_RBYTE(DMC_BSEL1) & DMC_RUN) == 0) {
    231 		printf("dmcprobe: can't start device\n" );
    232 		return (0);
    233 	}
    234 	DMC_WBYTE(DMC_BSEL0, DMC_RQI|DMC_IEI);
    235 	/* let's be paranoid */
    236 	DMC_WBYTE(DMC_BSEL0, DMC_RBYTE(DMC_BSEL0) | DMC_RQI|DMC_IEI);
    237 	DELAY(1000000);
    238 	DMC_WBYTE(DMC_BSEL1, DMC_MCLR);
    239 	for (i = 100000; i && (DMC_RBYTE(DMC_BSEL1) & DMC_RUN) == 0; i--)
    240 		;
    241 	return (1);
    242 }
    243 
    244 /*
    245  * Interface exists: make available by filling in network interface
    246  * record.  System will initialize the interface when it is ready
    247  * to accept packets.
    248  */
    249 void
    250 dmcattach(struct device *parent, struct device *self, void *aux)
    251 {
    252 	struct uba_attach_args *ua = aux;
    253 	struct dmc_softc *sc = device_private(self);
    254 
    255 	sc->sc_iot = ua->ua_iot;
    256 	sc->sc_ioh = ua->ua_ioh;
    257 	sc->sc_dmat = ua->ua_dmat;
    258 
    259 	strlcpy(sc->sc_if.if_xname, device_xname(&sc->sc_dev), IFNAMSIZ);
    260 	sc->sc_if.if_mtu = DMCMTU;
    261 	sc->sc_if.if_init = dmcinit;
    262 	sc->sc_if.if_output = dmcoutput;
    263 	sc->sc_if.if_ioctl = dmcioctl;
    264 	sc->sc_if.if_watchdog = dmctimeout;
    265 	sc->sc_if.if_flags = IFF_POINTOPOINT;
    266 	sc->sc_if.if_softc = sc;
    267 	IFQ_SET_READY(&sc->sc_if.if_snd);
    268 
    269 	uba_intr_establish(ua->ua_icookie, ua->ua_cvec, dmcrint, sc,
    270 	    &sc->sc_rintrcnt);
    271 	uba_intr_establish(ua->ua_icookie, ua->ua_cvec+4, dmcxint, sc,
    272 	    &sc->sc_tintrcnt);
    273 	uba_reset_establish(dmcreset, &sc->sc_dev);
    274 	evcnt_attach_dynamic(&sc->sc_rintrcnt, EVCNT_TYPE_INTR, ua->ua_evcnt,
    275 	    device_xname(&sc->sc_dev), "intr");
    276 	evcnt_attach_dynamic(&sc->sc_tintrcnt, EVCNT_TYPE_INTR, ua->ua_evcnt,
    277 	    device_xname(&sc->sc_dev), "intr");
    278 
    279 	if_attach(&sc->sc_if);
    280 }
    281 
    282 /*
    283  * Reset of interface after UNIBUS reset.
    284  * If interface is on specified UBA, reset its state.
    285  */
    286 void
    287 dmcreset(struct device *dev)
    288 {
    289 	struct dmc_softc *sc = (struct dmc_softc *)dev;
    290 
    291 	sc->sc_flag = 0;
    292 	sc->sc_if.if_flags &= ~IFF_RUNNING;
    293 	dmcinit(&sc->sc_if);
    294 }
    295 
    296 /*
    297  * Initialization of interface; reinitialize UNIBUS usage.
    298  */
    299 int
    300 dmcinit(struct ifnet *ifp)
    301 {
    302 	struct dmc_softc *sc = ifp->if_softc;
    303 	struct ifrw *ifrw;
    304 	struct ifxmt *ifxp;
    305 	struct dmcbufs *rp;
    306 	struct dmc_command *qp;
    307 	struct ifaddr *ifa;
    308 	struct cfdata *ui = device_cfdata(&sc->sc_dev);
    309 	int base;
    310 	int s;
    311 
    312 	/*
    313 	 * Check to see that an address has been set
    314 	 * (both local and destination for an address family).
    315 	 */
    316 	IFADDR_FOREACH(ifa, ifp)
    317 		if (ifa->ifa_addr->sa_family && ifa->ifa_dstaddr->sa_family)
    318 			break;
    319 	if (ifa == (struct ifaddr *) 0)
    320 		return 0;
    321 
    322 	if ((DMC_RBYTE(DMC_BSEL1) & DMC_RUN) == 0) {
    323 		printf("dmcinit: DMC not running\n");
    324 		ifp->if_flags &= ~IFF_UP;
    325 		return 0;
    326 	}
    327 	/* map base table */
    328 	if ((sc->sc_flag & DMC_BMAPPED) == 0) {
    329 		sc->sc_ui.ui_size = sizeof(struct dmc_base);
    330 		sc->sc_ui.ui_vaddr = (void *)&sc->dmc_base;
    331 		uballoc((void *)device_parent(&sc->sc_dev), &sc->sc_ui, 0);
    332 		sc->sc_flag |= DMC_BMAPPED;
    333 	}
    334 	/* initialize UNIBUS resources */
    335 	sc->sc_iused = sc->sc_oused = 0;
    336 	if ((ifp->if_flags & IFF_RUNNING) == 0) {
    337 		if (if_ubaminit(&sc->sc_ifuba,
    338 		    (void *)device_parent(&sc->sc_dev),
    339 		    sizeof(struct dmc_header) + DMCMTU,
    340 		    sc->sc_ifr, NRCV, sc->sc_ifw, NXMT) == 0) {
    341 			aprint_error_dev(&sc->sc_dev, "can't allocate uba resources\n");
    342 			ifp->if_flags &= ~IFF_UP;
    343 			return 0;
    344 		}
    345 		ifp->if_flags |= IFF_RUNNING;
    346 	}
    347 	sc->sc_flag &= ~DMC_ONLINE;
    348 	sc->sc_flag |= DMC_RUNNING;
    349 	/*
    350 	 * Limit packets enqueued until we see if we're on the air.
    351 	 */
    352 	ifp->if_snd.ifq_maxlen = 3;
    353 
    354 	/* initialize buffer pool */
    355 	/* receives */
    356 	ifrw = &sc->sc_ifr[0];
    357 	for (rp = &sc->sc_rbufs[0]; rp < &sc->sc_rbufs[NRCV]; rp++) {
    358 		rp->ubinfo = ifrw->ifrw_info;
    359 		rp->cc = DMCMTU + sizeof (struct dmc_header);
    360 		rp->flags = DBUF_OURS|DBUF_RCV;
    361 		ifrw++;
    362 	}
    363 	/* transmits */
    364 	ifxp = &sc->sc_ifw[0];
    365 	for (rp = &sc->sc_xbufs[0]; rp < &sc->sc_xbufs[NXMT]; rp++) {
    366 		rp->ubinfo = ifxp->ifw_info;
    367 		rp->cc = 0;
    368 		rp->flags = DBUF_OURS|DBUF_XMIT;
    369 		ifxp++;
    370 	}
    371 
    372 	/* set up command queues */
    373 	sc->sc_qfreeh = sc->sc_qfreet
    374 		 = sc->sc_qhead = sc->sc_qtail = sc->sc_qactive =
    375 		(struct dmc_command *)0;
    376 	/* set up free command buffer list */
    377 	for (qp = &sc->sc_cmdbuf[0]; qp < &sc->sc_cmdbuf[NCMDS]; qp++) {
    378 		QUEUE_AT_HEAD(qp, sc->sc_qfreeh, sc->sc_qfreet);
    379 	}
    380 
    381 	/* base in */
    382 	base = sc->sc_ui.ui_baddr;
    383 	dmcload(sc, DMC_BASEI, (u_short)base, (base>>2) & DMC_XMEM);
    384 	/* specify half duplex operation, flags tell if primary */
    385 	/* or secondary station */
    386 	if (ui->cf_flags == 0)
    387 		/* use DDCMP mode in full duplex */
    388 		dmcload(sc, DMC_CNTLI, 0, 0);
    389 	else if (ui->cf_flags == 1)
    390 		/* use MAINTENENCE mode */
    391 		dmcload(sc, DMC_CNTLI, 0, DMC_MAINT );
    392 	else if (ui->cf_flags == 2)
    393 		/* use DDCMP half duplex as primary station */
    394 		dmcload(sc, DMC_CNTLI, 0, DMC_HDPLX);
    395 	else if (ui->cf_flags == 3)
    396 		/* use DDCMP half duplex as secondary station */
    397 		dmcload(sc, DMC_CNTLI, 0, DMC_HDPLX | DMC_SEC);
    398 
    399 	/* enable operation done interrupts */
    400 	while ((DMC_RBYTE(DMC_BSEL2) & DMC_IEO) == 0)
    401 		DMC_WBYTE(DMC_BSEL2, DMC_RBYTE(DMC_BSEL2) | DMC_IEO);
    402 	s = splnet();
    403 	/* queue first NRCV buffers for DMC to fill */
    404 	for (rp = &sc->sc_rbufs[0]; rp < &sc->sc_rbufs[NRCV]; rp++) {
    405 		rp->flags |= DBUF_DMCS;
    406 		dmcload(sc, DMC_READ, rp->ubinfo,
    407 			(((rp->ubinfo>>2)&DMC_XMEM) | rp->cc));
    408 		sc->sc_iused++;
    409 	}
    410 	splx(s);
    411 	return 0;
    412 }
    413 
    414 /*
    415  * Start output on interface.  Get another datagram
    416  * to send from the interface queue and map it to
    417  * the interface before starting output.
    418  *
    419  * Must be called at spl 5
    420  */
    421 void
    422 dmcstart(struct ifnet *ifp)
    423 {
    424 	struct dmc_softc *sc = ifp->if_softc;
    425 	struct mbuf *m;
    426 	struct dmcbufs *rp;
    427 	int n;
    428 
    429 	/*
    430 	 * Dequeue up to NXMT requests and map them to the UNIBUS.
    431 	 * If no more requests, or no dmc buffers available, just return.
    432 	 */
    433 	n = 0;
    434 	for (rp = &sc->sc_xbufs[0]; rp < &sc->sc_xbufs[NXMT]; rp++ ) {
    435 		/* find an available buffer */
    436 		if ((rp->flags & DBUF_DMCS) == 0) {
    437 			IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
    438 			if (m == 0)
    439 				return;
    440 			/* mark it dmcs */
    441 			rp->flags |= (DBUF_DMCS);
    442 			/*
    443 			 * Have request mapped to UNIBUS for transmission
    444 			 * and start the output.
    445 			 */
    446 			rp->cc = if_ubaput(&sc->sc_ifuba, &sc->sc_ifw[n], m);
    447 			rp->cc &= DMC_CCOUNT;
    448 			if (++sc->sc_oused == 1)
    449 				sc->sc_if.if_timer = dmc_timeout;
    450 			dmcload(sc, DMC_WRITE, rp->ubinfo,
    451 				rp->cc | ((rp->ubinfo>>2)&DMC_XMEM));
    452 		}
    453 		n++;
    454 	}
    455 }
    456 
    457 /*
    458  * Utility routine to load the DMC device registers.
    459  */
    460 void
    461 dmcload(struct dmc_softc *sc, int type, u_short w0, u_short w1)
    462 {
    463 	struct dmc_command *qp;
    464 	int sps;
    465 
    466 	sps = splnet();
    467 
    468 	/* grab a command buffer from the free list */
    469 	if ((qp = sc->sc_qfreeh) == (struct dmc_command *)0)
    470 		panic("dmc command queue overflow");
    471 	DEQUEUE(sc->sc_qfreeh, sc->sc_qfreet);
    472 
    473 	/* fill in requested info */
    474 	qp->qp_cmd = (type | DMC_RQI);
    475 	qp->qp_ubaddr = w0;
    476 	qp->qp_cc = w1;
    477 
    478 	if (sc->sc_qactive) {	/* command in progress */
    479 		if (type == DMC_READ) {
    480 			QUEUE_AT_HEAD(qp, sc->sc_qhead, sc->sc_qtail);
    481 		} else {
    482 			QUEUE_AT_TAIL(qp, sc->sc_qhead, sc->sc_qtail);
    483 		}
    484 	} else {	/* command port free */
    485 		sc->sc_qactive = qp;
    486 		DMC_WBYTE(DMC_BSEL0, qp->qp_cmd);
    487 		dmcrint(sc);
    488 	}
    489 	splx(sps);
    490 }
    491 
    492 /*
    493  * DMC interface receiver interrupt.
    494  * Ready to accept another command,
    495  * pull one off the command queue.
    496  */
    497 void
    498 dmcrint(void *arg)
    499 {
    500 	struct dmc_softc *sc = arg;
    501 	struct dmc_command *qp;
    502 	int n;
    503 
    504 	if ((qp = sc->sc_qactive) == (struct dmc_command *) 0) {
    505 		printf("%s: dmcrint no command\n", device_xname(&sc->sc_dev));
    506 		return;
    507 	}
    508 	while (DMC_RBYTE(DMC_BSEL0) & DMC_RDYI) {
    509 		DMC_WWORD(DMC_SEL4, qp->qp_ubaddr);
    510 		DMC_WWORD(DMC_SEL6, qp->qp_cc);
    511 		DMC_WBYTE(DMC_BSEL0, DMC_RBYTE(DMC_BSEL0) & ~(DMC_IEI|DMC_RQI));
    512 		/* free command buffer */
    513 		QUEUE_AT_HEAD(qp, sc->sc_qfreeh, sc->sc_qfreet);
    514 		while (DMC_RBYTE(DMC_BSEL0) & DMC_RDYI) {
    515 			/*
    516 			 * Can't check for RDYO here 'cause
    517 			 * this routine isn't reentrant!
    518 			 */
    519 			DELAY(5);
    520 		}
    521 		/* move on to next command */
    522 		if ((sc->sc_qactive = sc->sc_qhead) == (struct dmc_command *)0)
    523 			break;		/* all done */
    524 		/* more commands to do, start the next one */
    525 		qp = sc->sc_qactive;
    526 		DEQUEUE(sc->sc_qhead, sc->sc_qtail);
    527 		DMC_WBYTE(DMC_BSEL0, qp->qp_cmd);
    528 		n = RDYSCAN;
    529 		while (n-- > 0)
    530 			if ((DMC_RBYTE(DMC_BSEL0) & DMC_RDYI) ||
    531 			    (DMC_RBYTE(DMC_BSEL2) & DMC_RDYO))
    532 				break;
    533 	}
    534 	if (sc->sc_qactive) {
    535 		DMC_WBYTE(DMC_BSEL0, DMC_RBYTE(DMC_BSEL0) & (DMC_IEI|DMC_RQI));
    536 		/* VMS does it twice !*$%@# */
    537 		DMC_WBYTE(DMC_BSEL0, DMC_RBYTE(DMC_BSEL0) & (DMC_IEI|DMC_RQI));
    538 	}
    539 
    540 }
    541 
    542 /*
    543  * DMC interface transmitter interrupt.
    544  * A transfer may have completed, check for errors.
    545  * If it was a read, notify appropriate protocol.
    546  * If it was a write, pull the next one off the queue.
    547  */
    548 void
    549 dmcxint(void *a)
    550 {
    551 	struct dmc_softc *sc = a;
    552 
    553 	struct ifnet *ifp;
    554 	struct mbuf *m;
    555 	struct ifqueue *inq;
    556 	int arg, pkaddr, cmd, len, s;
    557 	struct ifrw *ifrw;
    558 	struct dmcbufs *rp;
    559 	struct ifxmt *ifxp;
    560 	struct dmc_header *dh;
    561 	char buf[64];
    562 
    563 	ifp = &sc->sc_if;
    564 
    565 	while (DMC_RBYTE(DMC_BSEL2) & DMC_RDYO) {
    566 
    567 		cmd = DMC_RBYTE(DMC_BSEL2) & 0xff;
    568 		arg = DMC_RWORD(DMC_SEL6) & 0xffff;
    569 		/* reconstruct UNIBUS address of buffer returned to us */
    570 		pkaddr = ((arg&DMC_XMEM)<<2) | (DMC_RWORD(DMC_SEL4) & 0xffff);
    571 		/* release port */
    572 		DMC_WBYTE(DMC_BSEL2, DMC_RBYTE(DMC_BSEL2) & ~DMC_RDYO);
    573 		switch (cmd & 07) {
    574 
    575 		case DMC_OUR:
    576 			/*
    577 			 * A read has completed.
    578 			 * Pass packet to type specific
    579 			 * higher-level input routine.
    580 			 */
    581 			ifp->if_ipackets++;
    582 			/* find location in dmcuba struct */
    583 			ifrw= &sc->sc_ifr[0];
    584 			for (rp = &sc->sc_rbufs[0]; rp < &sc->sc_rbufs[NRCV]; rp++) {
    585 				if(rp->ubinfo == pkaddr)
    586 					break;
    587 				ifrw++;
    588 			}
    589 			if (rp >= &sc->sc_rbufs[NRCV])
    590 				panic("dmc rcv");
    591 			if ((rp->flags & DBUF_DMCS) == 0)
    592 				aprint_error_dev(&sc->sc_dev, "done unalloc rbuf\n");
    593 
    594 			len = (arg & DMC_CCOUNT) - sizeof (struct dmc_header);
    595 			if (len < 0 || len > DMCMTU) {
    596 				ifp->if_ierrors++;
    597 #ifdef DMCDEBUG
    598 				printd("%s: bad rcv pkt addr 0x%x len 0x%x\n",
    599 				    device_xname(&sc->sc_dev), pkaddr, len);
    600 #endif
    601 				goto setup;
    602 			}
    603 			/*
    604 			 * Deal with trailer protocol: if type is trailer
    605 			 * get true type from first 16-bit word past data.
    606 			 * Remember that type was trailer by setting off.
    607 			 */
    608 			dh = (struct dmc_header *)ifrw->ifrw_addr;
    609 			dh->dmc_type = ntohs((u_short)dh->dmc_type);
    610 			if (len == 0)
    611 				goto setup;
    612 
    613 			/*
    614 			 * Pull packet off interface.  Off is nonzero if
    615 			 * packet has trailing header; dmc_get will then
    616 			 * force this header information to be at the front,
    617 			 * but we still have to drop the type and length
    618 			 * which are at the front of any trailer data.
    619 			 */
    620 			m = if_ubaget(&sc->sc_ifuba, ifrw, ifp, len);
    621 			if (m == 0)
    622 				goto setup;
    623 			/* Shave off dmc_header */
    624 			m_adj(m, sizeof(struct dmc_header));
    625 			switch (dh->dmc_type) {
    626 
    627 #ifdef INET
    628 			case DMC_IPTYPE:
    629 				schednetisr(NETISR_IP);
    630 				inq = &ipintrq;
    631 				break;
    632 #endif
    633 			default:
    634 				m_freem(m);
    635 				goto setup;
    636 			}
    637 
    638 			s = splnet();
    639 			if (IF_QFULL(inq)) {
    640 				IF_DROP(inq);
    641 				m_freem(m);
    642 			} else
    643 				IF_ENQUEUE(inq, m);
    644 			splx(s);
    645 
    646 	setup:
    647 			/* is this needed? */
    648 			rp->ubinfo = ifrw->ifrw_info;
    649 
    650 			dmcload(sc, DMC_READ, rp->ubinfo,
    651 			    ((rp->ubinfo >> 2) & DMC_XMEM) | rp->cc);
    652 			break;
    653 
    654 		case DMC_OUX:
    655 			/*
    656 			 * A write has completed, start another
    657 			 * transfer if there is more data to send.
    658 			 */
    659 			ifp->if_opackets++;
    660 			/* find associated dmcbuf structure */
    661 			ifxp = &sc->sc_ifw[0];
    662 			for (rp = &sc->sc_xbufs[0]; rp < &sc->sc_xbufs[NXMT]; rp++) {
    663 				if(rp->ubinfo == pkaddr)
    664 					break;
    665 				ifxp++;
    666 			}
    667 			if (rp >= &sc->sc_xbufs[NXMT]) {
    668 				aprint_error_dev(&sc->sc_dev, "bad packet address 0x%x\n",
    669 				    pkaddr);
    670 				break;
    671 			}
    672 			if ((rp->flags & DBUF_DMCS) == 0)
    673 				aprint_error_dev(&sc->sc_dev, "unallocated packet 0x%x\n",
    674 				    pkaddr);
    675 			/* mark buffer free */
    676 			if_ubaend(&sc->sc_ifuba, ifxp);
    677 			rp->flags &= ~DBUF_DMCS;
    678 			if (--sc->sc_oused == 0)
    679 				sc->sc_if.if_timer = 0;
    680 			else
    681 				sc->sc_if.if_timer = dmc_timeout;
    682 			if ((sc->sc_flag & DMC_ONLINE) == 0) {
    683 				extern int ifqmaxlen;
    684 
    685 				/*
    686 				 * We're on the air.
    687 				 * Open the queue to the usual value.
    688 				 */
    689 				sc->sc_flag |= DMC_ONLINE;
    690 				ifp->if_snd.ifq_maxlen = ifqmaxlen;
    691 			}
    692 			break;
    693 
    694 		case DMC_CNTLO:
    695 			arg &= DMC_CNTMASK;
    696 			if (arg & DMC_FATAL) {
    697 				if (arg != DMC_START) {
    698 					bitmask_snprintf(arg, CNTLO_BITS,
    699 					    buf, sizeof(buf));
    700 					log(LOG_ERR,
    701 					    "%s: fatal error, flags=%s\n",
    702 					    device_xname(&sc->sc_dev), buf);
    703 				}
    704 				dmcrestart(sc);
    705 				break;
    706 			}
    707 			/* ACCUMULATE STATISTICS */
    708 			switch(arg) {
    709 			case DMC_NOBUFS:
    710 				ifp->if_ierrors++;
    711 				if ((sc->sc_nobuf++ % DMC_RPNBFS) == 0)
    712 					goto report;
    713 				break;
    714 			case DMC_DISCONN:
    715 				if ((sc->sc_disc++ % DMC_RPDSC) == 0)
    716 					goto report;
    717 				break;
    718 			case DMC_TIMEOUT:
    719 				if ((sc->sc_timeo++ % DMC_RPTMO) == 0)
    720 					goto report;
    721 				break;
    722 			case DMC_DATACK:
    723 				ifp->if_oerrors++;
    724 				if ((sc->sc_datck++ % DMC_RPDCK) == 0)
    725 					goto report;
    726 				break;
    727 			default:
    728 				goto report;
    729 			}
    730 			break;
    731 		report:
    732 #ifdef DMCDEBUG
    733 			bitmask_snprintf(arg, CNTLO_BITS, buf, sizeof(buf));
    734 			printd("%s: soft error, flags=%s\n",
    735 			    device_xname(&sc->sc_dev), buf);
    736 #endif
    737 			if ((sc->sc_flag & DMC_RESTART) == 0) {
    738 				/*
    739 				 * kill off the dmc to get things
    740 				 * going again by generating a
    741 				 * procedure error
    742 				 */
    743 				sc->sc_flag |= DMC_RESTART;
    744 				arg = sc->sc_ui.ui_baddr;
    745 				dmcload(sc, DMC_BASEI, arg, (arg>>2)&DMC_XMEM);
    746 			}
    747 			break;
    748 
    749 		default:
    750 			printf("%s: bad control %o\n",
    751 			    device_xname(&sc->sc_dev), cmd);
    752 			break;
    753 		}
    754 	}
    755 	dmcstart(ifp);
    756 }
    757 
    758 /*
    759  * DMC output routine.
    760  * Encapsulate a packet of type family for the dmc.
    761  * Use trailer local net encapsulation if enough data in first
    762  * packet leaves a multiple of 512 bytes of data in remainder.
    763  */
    764 int
    765 dmcoutput(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
    766     struct rtentry *rt)
    767 {
    768 	int type, error, s;
    769 	struct mbuf *m = m0;
    770 	struct dmc_header *dh;
    771 	ALTQ_DECL(struct altq_pktattr pktattr;)
    772 
    773 	if ((ifp->if_flags & IFF_UP) == 0) {
    774 		error = ENETDOWN;
    775 		goto bad;
    776 	}
    777 
    778 	IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr);
    779 
    780 	switch (dst->sa_family) {
    781 #ifdef	INET
    782 	case AF_INET:
    783 		type = DMC_IPTYPE;
    784 		break;
    785 #endif
    786 
    787 	case AF_UNSPEC:
    788 		dh = (struct dmc_header *)dst->sa_data;
    789 		type = dh->dmc_type;
    790 		break;
    791 
    792 	default:
    793 		printf("%s: can't handle af%d\n", ifp->if_xname,
    794 			dst->sa_family);
    795 		error = EAFNOSUPPORT;
    796 		goto bad;
    797 	}
    798 
    799 	/*
    800 	 * Add local network header
    801 	 * (there is space for a uba on a vax to step on)
    802 	 */
    803 	M_PREPEND(m, sizeof(struct dmc_header), M_DONTWAIT);
    804 	if (m == 0) {
    805 		error = ENOBUFS;
    806 		goto bad;
    807 	}
    808 	dh = mtod(m, struct dmc_header *);
    809 	dh->dmc_type = htons((u_short)type);
    810 
    811 	/*
    812 	 * Queue message on interface, and start output if interface
    813 	 * not yet active.
    814 	 */
    815 	s = splnet();
    816 	IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error);
    817 	if (error) {
    818 		/* mbuf is already freed */
    819 		splx(s);
    820 		return (error);
    821 	}
    822 	dmcstart(ifp);
    823 	splx(s);
    824 	return (0);
    825 
    826 bad:
    827 	m_freem(m0);
    828 	return (error);
    829 }
    830 
    831 
    832 /*
    833  * Process an ioctl request.
    834  */
    835 /* ARGSUSED */
    836 int
    837 dmcioctl(struct ifnet *ifp, u_long cmd, void *data)
    838 {
    839 	int s = splnet(), error = 0;
    840 	register struct dmc_softc *sc = ifp->if_softc;
    841 
    842 	switch (cmd) {
    843 
    844 	case SIOCINITIFADDR:
    845 		ifp->if_flags |= IFF_UP;
    846 		if ((ifp->if_flags & IFF_RUNNING) == 0)
    847 			dmcinit(ifp);
    848 		break;
    849 
    850 	case SIOCSIFDSTADDR:
    851 		if ((ifp->if_flags & IFF_RUNNING) == 0)
    852 			dmcinit(ifp);
    853 		break;
    854 
    855 	case SIOCSIFFLAGS:
    856 		if ((error = ifioctl_common(ifp, cmd, data)) != 0)
    857 			break;
    858 		if ((ifp->if_flags & IFF_UP) == 0 &&
    859 		    sc->sc_flag & DMC_RUNNING)
    860 			dmcdown(sc);
    861 		else if (ifp->if_flags & IFF_UP &&
    862 		    (sc->sc_flag & DMC_RUNNING) == 0)
    863 			dmcrestart(sc);
    864 		break;
    865 
    866 	default:
    867 		error = ifioctl_common(ifp, cmd, data);
    868 	}
    869 	splx(s);
    870 	return (error);
    871 }
    872 
    873 /*
    874  * Restart after a fatal error.
    875  * Clear device and reinitialize.
    876  */
    877 void
    878 dmcrestart(struct dmc_softc *sc)
    879 {
    880 	int s, i;
    881 
    882 #ifdef DMCDEBUG
    883 	/* dump base table */
    884 	printf("%s base table:\n", device_xname(&sc->sc_dev));
    885 	for (i = 0; i < sizeof (struct dmc_base); i++)
    886 		printf("%o\n" ,dmc_base[unit].d_base[i]);
    887 #endif
    888 
    889 	dmcdown(sc);
    890 
    891 	/*
    892 	 * Let the DMR finish the MCLR.	 At 1 Mbit, it should do so
    893 	 * in about a max of 6.4 milliseconds with diagnostics enabled.
    894 	 */
    895 	for (i = 100000; i && (DMC_RBYTE(DMC_BSEL1) & DMC_RUN) == 0; i--)
    896 		;
    897 	/* Did the timer expire or did the DMR finish? */
    898 	if ((DMC_RBYTE(DMC_BSEL1) & DMC_RUN) == 0) {
    899 		log(LOG_ERR, "%s: M820 Test Failed\n", device_xname(&sc->sc_dev));
    900 		return;
    901 	}
    902 
    903 	/* restart DMC */
    904 	dmcinit(&sc->sc_if);
    905 	sc->sc_flag &= ~DMC_RESTART;
    906 	s = splnet();
    907 	dmcstart(&sc->sc_if);
    908 	splx(s);
    909 	sc->sc_if.if_collisions++;	/* why not? */
    910 }
    911 
    912 /*
    913  * Reset a device and mark down.
    914  * Flush output queue and drop queue limit.
    915  */
    916 void
    917 dmcdown(struct dmc_softc *sc)
    918 {
    919 	struct ifxmt *ifxp;
    920 
    921 	DMC_WBYTE(DMC_BSEL1, DMC_MCLR);
    922 	sc->sc_flag &= ~(DMC_RUNNING | DMC_ONLINE);
    923 
    924 	for (ifxp = sc->sc_ifw; ifxp < &sc->sc_ifw[NXMT]; ifxp++) {
    925 #ifdef notyet
    926 		if (ifxp->ifw_xtofree) {
    927 			(void) m_freem(ifxp->ifw_xtofree);
    928 			ifxp->ifw_xtofree = 0;
    929 		}
    930 #endif
    931 	}
    932 	IF_PURGE(&sc->sc_if.if_snd);
    933 }
    934 
    935 /*
    936  * Watchdog timeout to see that transmitted packets don't
    937  * lose interrupts.  The device has to be online (the first
    938  * transmission may block until the other side comes up).
    939  */
    940 void
    941 dmctimeout(struct ifnet *ifp)
    942 {
    943 	struct dmc_softc *sc = ifp->if_softc;
    944 	char buf1[64], buf2[64];
    945 
    946 	if (sc->sc_flag & DMC_ONLINE) {
    947 		bitmask_snprintf(DMC_RBYTE(DMC_BSEL0) & 0xff, DMC0BITS,
    948 		    buf1, sizeof(buf1));
    949 		bitmask_snprintf(DMC_RBYTE(DMC_BSEL2) & 0xff, DMC2BITS,
    950 		    buf2, sizeof(buf2));
    951 		log(LOG_ERR, "%s: output timeout, bsel0=%s bsel2=%s\n",
    952 		    device_xname(&sc->sc_dev), buf1, buf2);
    953 		dmcrestart(sc);
    954 	}
    955 }
    956