usr/src/sys/vax/if/if_acc.c

/*	if_acc.c	4.20	82/10/09	*/

#include "acc.h"
#ifdef NACC > 0

/*
 * ACC LH/DH ARPAnet IMP interface driver.
 */

#include "../h/param.h"
#include "../h/systm.h"
#include "../h/mbuf.h"
#include "../h/pte.h"
#include "../h/buf.h"
#include "../h/protosw.h"
#include "../h/socket.h"
#include "../h/ubareg.h"
#include "../h/ubavar.h"
#include "../h/cpu.h"
#include "../h/mtpr.h"
#include "../h/vmmac.h"
#include "../net/if.h"
#include "../vaxif/if_acc.h"
#include "../netimp/if_imp.h"
#include "../vaxif/if_uba.h"

int     accprobe(), accattach(), accrint(), accxint();
struct  uba_device *accinfo[NACC];
u_short accstd[] = { 0 };
struct  uba_driver accdriver =
	{ accprobe, 0, accattach, 0, accstd, "acc", accinfo };
#define	ACCUNIT(x)	minor(x)

int	accinit(), accstart(), accreset();

/*
 * "Lower half" of IMP interface driver.
 *
 * Each IMP interface is handled by a common module which handles
 * the IMP-host protocol and a hardware driver which manages the
 * hardware specific details of talking with the IMP.
 *
 * The hardware portion of the IMP driver handles DMA and related
 * management of UNIBUS resources.  The IMP protocol module interprets
 * contents of these messages and "controls" the actions of the
 * hardware module during IMP resets, but not, for instance, during
 * UNIBUS resets.
 *
 * The two modules are coupled at "attach time", and ever after,
 * through the imp interface structure.  Higher level protocols,
 * e.g. IP, interact with the IMP driver, rather than the ACC.
 */
struct	acc_softc {
	struct	ifnet *acc_if;		/* pointer to IMP's ifnet struct */
	struct	impcb *acc_ic;		/* data structure shared with IMP */
	struct	ifuba acc_ifuba;	/* UNIBUS resources */
	struct	mbuf *acc_iq;		/* input reassembly queue */
	short	acc_olen;		/* size of last message sent */
	char	acc_flush;		/* flush remainder of message */
} acc_softc[NACC];

/*
 * Reset the IMP and cause a transmitter interrupt by
 * performing a null DMA.
 */
accprobe(reg)
	caddr_t reg;
{
	register int br, cvec;		/* r11, r10 value-result */
	register struct accdevice *addr = (struct accdevice *)reg;

#ifdef lint
	br = 0; cvec = br; br = cvec;
	accrint(0); accxint(0);
#endif
	addr->icsr = ACC_RESET; DELAY(5000);
	addr->ocsr = ACC_RESET; DELAY(5000);
	addr->ocsr = OUT_BBACK; DELAY(5000);
	addr->owc = 0;
	addr->ocsr = ACC_IE | ACC_GO; DELAY(5000);
	addr->ocsr = 0;
	if (cvec && cvec != 0x200)	/* transmit -> receive */
		cvec -= 4;
#ifdef ECHACK
	br = 0x16;
#endif
	return (1);
}

/*
 * Call the IMP module to allow it to set up its internal
 * state, then tie the two modules together by setting up
 * the back pointers to common data structures.
 */
accattach(ui)
	struct uba_device *ui;
{
	register struct acc_softc *sc = &acc_softc[ui->ui_unit];
	register struct impcb *ip;
	struct ifimpcb {
		struct	ifnet ifimp_if;
		struct	impcb ifimp_impcb;
	} *ifimp;

	if ((ifimp = (struct ifimpcb *)impattach(ui)) == 0)
		panic("accattach");
	sc->acc_if = &ifimp->ifimp_if;
	ip = &ifimp->ifimp_impcb;
	sc->acc_ic = ip;
	ip->ic_init = accinit;
	ip->ic_start = accstart;
	sc->acc_ifuba.ifu_flags = UBA_CANTWAIT;
#ifdef notdef
	sc->acc_ifuba.ifu_flags |= UBA_NEEDBDP;
#endif
}

/*
 * Reset interface after UNIBUS reset.
 * If interface is on specified uba, reset its state.
 */
accreset(unit, uban)
	int unit, uban;
{
	register struct uba_device *ui;
	struct acc_softc *sc;

	if (unit >= NACC || (ui = accinfo[unit]) == 0 || ui->ui_alive == 0 ||
	    ui->ui_ubanum != uban)
		return;
	printf(" acc%d", unit);
	sc = &acc_softc[unit];
	/* must go through IMP to allow it to set state */
	(*sc->acc_if->if_init)(unit);
}

/*
 * Initialize interface: clear recorded pending operations,
 * and retrieve, and initialize UNIBUS resources.  Note
 * return value is used by IMP init routine to mark IMP
 * unavailable for outgoing traffic.
 */
accinit(unit)
	int unit;
{
	register struct acc_softc *sc;
	register struct uba_device *ui;
	register struct accdevice *addr;
	int info, i;

	if (unit >= NACC || (ui = accinfo[unit]) == 0 || ui->ui_alive == 0) {
		printf("acc%d: not alive\n", unit);
		return (0);
	}
	sc = &acc_softc[unit];
	/*
	 * Header length is 0 since we have to passs
	 * the IMP leader up to the protocol interpretation
	 * routines.  If we had the header length as
	 * sizeof(struct imp_leader), then the if_ routines
	 * would asssume we handle it on input and output.
	 */
	if (if_ubainit(&sc->acc_ifuba, ui->ui_ubanum, 0,
	     (int)btoc(IMPMTU)) == 0) {
		printf("acc%d: can't initialize\n", unit);
		ui->ui_alive = 0;
		return (0);
	}
	addr = (struct accdevice *)ui->ui_addr;

	/*
	 * Reset the imp interface;
	 * the delays are pure guesswork.
	 */
        addr->ocsr = ACC_RESET; DELAY(5000);
	addr->ocsr = OUT_BBACK;	DELAY(5000);	/* reset host master ready */
	addr->ocsr = 0;
	if (accinputreset(addr, unit) == 0) {
		ui->ui_alive = 0;
		return (0);
	}

	/*
	 * Put up a read.  We can't restart any outstanding writes
	 * until we're back in synch with the IMP (i.e. we've flushed
	 * the NOOPs it throws at us).
	 * Note: IMPMTU includes the leader.
	 */
	info = sc->acc_ifuba.ifu_r.ifrw_info;
	addr->iba = (u_short)info;
	addr->iwc = -(IMPMTU >> 1);
#ifdef LOOPBACK
	addr->ocsr |= OUT_BBACK;
#endif
	addr->icsr =
		IN_MRDY | ACC_IE | IN_WEN | ((info & 0x30000) >> 12) | ACC_GO;
	return (1);
}

accinputreset(addr, unit)
	register struct accdevice *addr;
	register int unit;
{
	register int i;

	addr->icsr = ACC_RESET; DELAY(5000);
	addr->icsr = IN_MRDY | IN_WEN;		/* close the relay */
	DELAY(10000);
	/* YECH!!! */
	for (i = 0; i < 500; i++) {
		if ((addr->icsr & IN_HRDY) ||
		    (addr->icsr & (IN_RMR | IN_IMPBSY)) == 0)
			return (1);
		addr->icsr = IN_MRDY | IN_WEN; DELAY(10000);
		/* keep turning IN_RMR off */
	}
	printf("acc%d: imp doesn't respond, icsr=%b\n", unit,
		addr->icsr, ACC_INBITS);
	return (0);
}

/*
 * Start output on an interface.
 */
accstart(dev)
	dev_t dev;
{
	int unit = ACCUNIT(dev), info;
	register struct acc_softc *sc = &acc_softc[unit];
	register struct accdevice *addr;
	struct mbuf *m;
	u_short cmd;

	if (sc->acc_ic->ic_oactive)
		goto restart;

	/*
	 * Not already active, deqeue a request and
	 * map it onto the UNIBUS.  If no more
	 * requeusts, just return.
	 */
	IF_DEQUEUE(&sc->acc_if->if_snd, m);
	if (m == 0) {
		sc->acc_ic->ic_oactive = 0;
		return;
	}
	sc->acc_olen = if_wubaput(&sc->acc_ifuba, m);

restart:
	/*
	 * Have request mapped to UNIBUS for
	 * transmission; start the output.
	 */
	if (sc->acc_ifuba.ifu_flags & UBA_NEEDBDP)
		UBAPURGE(sc->acc_ifuba.ifu_uba, sc->acc_ifuba.ifu_w.ifrw_bdp);
	addr = (struct accdevice *)accinfo[unit]->ui_addr;
	info = sc->acc_ifuba.ifu_w.ifrw_info;
	addr->oba = (u_short)info;
	addr->owc = -((sc->acc_olen + 1) >> 1);
	cmd = ACC_IE | OUT_ENLB | ((info & 0x30000) >> 12) | ACC_GO;
#ifdef LOOPBACK
	cmd |= OUT_BBACK;
#endif
	addr->ocsr = cmd;
	sc->acc_ic->ic_oactive = 1;
}

/*
 * Output interrupt handler.
 */
accxint(unit)
	int unit;
{
	register struct acc_softc *sc = &acc_softc[unit];
	register struct accdevice *addr;

	addr = (struct accdevice *)accinfo[unit]->ui_addr;
	if (sc->acc_ic->ic_oactive == 0) {
		printf("acc%d: stray xmit interrupt, csr=%b\n", unit,
			addr->ocsr, ACC_OUTBITS);
		return;
	}
	sc->acc_if->if_opackets++;
	sc->acc_ic->ic_oactive = 0;
	if (addr->ocsr & ACC_ERR) {
		printf("acc%d: output error, ocsr=%b, icsr=%b\n", unit,
			addr->ocsr, ACC_OUTBITS, addr->icsr, ACC_INBITS);
		sc->acc_if->if_oerrors++;
	}
	if (sc->acc_ifuba.ifu_xtofree) {
		m_freem(sc->acc_ifuba.ifu_xtofree);
		sc->acc_ifuba.ifu_xtofree = 0;
	}
	if (sc->acc_if->if_snd.ifq_head)
		accstart(unit);
}

/*
 * Input interrupt handler
 */
accrint(unit)
	int unit;
{
	register struct acc_softc *sc = &acc_softc[unit];
	register struct accdevice *addr;
    	struct mbuf *m;
	int len, info;

	addr = (struct accdevice *)accinfo[unit]->ui_addr;
	sc->acc_if->if_ipackets++;

	/*
	 * Purge BDP; flush message if error indicated.
	 */
	if (sc->acc_ifuba.ifu_flags & UBA_NEEDBDP)
		UBAPURGE(sc->acc_ifuba.ifu_uba, sc->acc_ifuba.ifu_r.ifrw_bdp);
	if (addr->icsr & ACC_ERR) {
		printf("acc%d: input error, csr=%b\n", unit,
		    addr->icsr, ACC_INBITS);
		sc->acc_if->if_ierrors++;
		sc->acc_flush = 1;
	}

	if (sc->acc_flush) {
		if (addr->icsr & IN_EOM)
			sc->acc_flush = 0;
		goto setup;
	}
	len = IMPMTU + (addr->iwc << 1);
	if (len < 0 || len > IMPMTU) {
		printf("acc%d: bad length=%d\n", len);
		sc->acc_if->if_ierrors++;
		goto setup;
	}

	/*
	 * The last parameter is always 0 since using
	 * trailers on the ARPAnet is insane.
	 */
	m = if_rubaget(&sc->acc_ifuba, len, 0);
	if (m == 0)
		goto setup;
	if ((addr->icsr & IN_EOM) == 0) {
		if (sc->acc_iq)
			m_cat(sc->acc_iq, m);
		else
			sc->acc_iq = m;
		goto setup;
	}
	if (sc->acc_iq) {
		m_cat(sc->acc_iq, m);
		m = sc->acc_iq;
		sc->acc_iq = 0;
	}
	impinput(unit, m);

setup:
	/*
	 * Setup for next message.
	 */
	info = sc->acc_ifuba.ifu_r.ifrw_info;
	addr->iba = (u_short)info;
	addr->iwc = -(IMPMTU >> 1);
	addr->icsr =
		IN_MRDY | ACC_IE | IN_WEN | ((info & 0x30000) >> 12) | ACC_GO;
}
#endif
Commit	Line	Data
	1	/* if_acc.c 4.20 82/10/09 */
	2
	3	#include "acc.h"
	4	#ifdef NACC > 0
	5
	6	/*
	7	* ACC LH/DH ARPAnet IMP interface driver.
	8	*/
	9
	10	#include "../h/param.h"
	11	#include "../h/systm.h"
	12	#include "../h/mbuf.h"
	13	#include "../h/pte.h"
	14	#include "../h/buf.h"
	15	#include "../h/protosw.h"
	16	#include "../h/socket.h"
	17	#include "../h/ubareg.h"
	18	#include "../h/ubavar.h"
	19	#include "../h/cpu.h"
	20	#include "../h/mtpr.h"
	21	#include "../h/vmmac.h"
	22	#include "../net/if.h"
	23	#include "../vaxif/if_acc.h"
	24	#include "../netimp/if_imp.h"
	25	#include "../vaxif/if_uba.h"
	26
	27	int accprobe(), accattach(), accrint(), accxint();
	28	struct uba_device *accinfo[NACC];
	29	u_short accstd[] = { 0 };
	30	struct uba_driver accdriver =
	31	{ accprobe, 0, accattach, 0, accstd, "acc", accinfo };
	32	#define ACCUNIT(x) minor(x)
	33
	34	int accinit(), accstart(), accreset();
	35
	36	/*
	37	* "Lower half" of IMP interface driver.
	38	*
	39	* Each IMP interface is handled by a common module which handles
	40	* the IMP-host protocol and a hardware driver which manages the
	41	* hardware specific details of talking with the IMP.
	42	*
	43	* The hardware portion of the IMP driver handles DMA and related
	44	* management of UNIBUS resources. The IMP protocol module interprets
	45	* contents of these messages and "controls" the actions of the
	46	* hardware module during IMP resets, but not, for instance, during
	47	* UNIBUS resets.
	48	*
	49	* The two modules are coupled at "attach time", and ever after,
	50	* through the imp interface structure. Higher level protocols,
	51	* e.g. IP, interact with the IMP driver, rather than the ACC.
	52	*/
	53	struct acc_softc {
	54	struct ifnet acc_if; / pointer to IMP's ifnet struct */
	55	struct impcb acc_ic; / data structure shared with IMP */
	56	struct ifuba acc_ifuba; /* UNIBUS resources */
	57	struct mbuf acc_iq; / input reassembly queue */
	58	short acc_olen; /* size of last message sent */
	59	char acc_flush; /* flush remainder of message */
	60	} acc_softc[NACC];
	61
	62	/*
	63	* Reset the IMP and cause a transmitter interrupt by
	64	* performing a null DMA.
	65	*/
	66	accprobe(reg)
	67	caddr_t reg;
	68	{
	69	register int br, cvec; /* r11, r10 value-result */
	70	register struct accdevice addr = (struct accdevice )reg;
	71
	72	#ifdef lint
	73	br = 0; cvec = br; br = cvec;
	74	accrint(0); accxint(0);
	75	#endif
	76	addr->icsr = ACC_RESET; DELAY(5000);
	77	addr->ocsr = ACC_RESET; DELAY(5000);
	78	addr->ocsr = OUT_BBACK; DELAY(5000);
	79	addr->owc = 0;
	80	addr->ocsr = ACC_IE \| ACC_GO; DELAY(5000);
	81	addr->ocsr = 0;
	82	if (cvec && cvec != 0x200) /* transmit -> receive */
	83	cvec -= 4;
	84	#ifdef ECHACK
	85	br = 0x16;
	86	#endif
	87	return (1);
	88	}
	89
	90	/*
	91	* Call the IMP module to allow it to set up its internal
	92	* state, then tie the two modules together by setting up
	93	* the back pointers to common data structures.
	94	*/
	95	accattach(ui)
	96	struct uba_device *ui;
	97	{
	98	register struct acc_softc *sc = &acc_softc[ui->ui_unit];
	99	register struct impcb *ip;
	100	struct ifimpcb {
	101	struct ifnet ifimp_if;
	102	struct impcb ifimp_impcb;
	103	} *ifimp;
	104
	105	if ((ifimp = (struct ifimpcb *)impattach(ui)) == 0)
	106	panic("accattach");
	107	sc->acc_if = &ifimp->ifimp_if;
	108	ip = &ifimp->ifimp_impcb;
	109	sc->acc_ic = ip;
	110	ip->ic_init = accinit;
	111	ip->ic_start = accstart;
	112	sc->acc_ifuba.ifu_flags = UBA_CANTWAIT;
	113	#ifdef notdef
	114	sc->acc_ifuba.ifu_flags \|= UBA_NEEDBDP;
	115	#endif
	116	}
	117
	118	/*
	119	* Reset interface after UNIBUS reset.
	120	* If interface is on specified uba, reset its state.
	121	*/
	122	accreset(unit, uban)
	123	int unit, uban;
	124	{
	125	register struct uba_device *ui;
	126	struct acc_softc *sc;
	127
	128	if (unit >= NACC \|\| (ui = accinfo[unit]) == 0 \|\| ui->ui_alive == 0 \|\|
	129	ui->ui_ubanum != uban)
	130	return;
	131	printf(" acc%d", unit);
	132	sc = &acc_softc[unit];
	133	/* must go through IMP to allow it to set state */
	134	(*sc->acc_if->if_init)(unit);
	135	}
	136
	137	/*
	138	* Initialize interface: clear recorded pending operations,
	139	* and retrieve, and initialize UNIBUS resources. Note
	140	* return value is used by IMP init routine to mark IMP
	141	* unavailable for outgoing traffic.
	142	*/
	143	accinit(unit)
	144	int unit;
	145	{
	146	register struct acc_softc *sc;
	147	register struct uba_device *ui;
	148	register struct accdevice *addr;
	149	int info, i;
	150
	151	if (unit >= NACC \|\| (ui = accinfo[unit]) == 0 \|\| ui->ui_alive == 0) {
	152	printf("acc%d: not alive\n", unit);
	153	return (0);
	154	}
	155	sc = &acc_softc[unit];
	156	/*
	157	* Header length is 0 since we have to passs
	158	* the IMP leader up to the protocol interpretation
	159	* routines. If we had the header length as
	160	* sizeof(struct imp_leader), then the if_ routines
	161	* would asssume we handle it on input and output.
	162	*/
	163	if (if_ubainit(&sc->acc_ifuba, ui->ui_ubanum, 0,
	164	(int)btoc(IMPMTU)) == 0) {
	165	printf("acc%d: can't initialize\n", unit);
	166	ui->ui_alive = 0;
	167	return (0);
	168	}
	169	addr = (struct accdevice *)ui->ui_addr;
	170
	171	/*
	172	* Reset the imp interface;
	173	* the delays are pure guesswork.
	174	*/
	175	addr->ocsr = ACC_RESET; DELAY(5000);
	176	addr->ocsr = OUT_BBACK; DELAY(5000); /* reset host master ready */
	177	addr->ocsr = 0;
	178	if (accinputreset(addr, unit) == 0) {
	179	ui->ui_alive = 0;
	180	return (0);
	181	}
	182
	183	/*
	184	* Put up a read. We can't restart any outstanding writes
	185	* until we're back in synch with the IMP (i.e. we've flushed
	186	* the NOOPs it throws at us).
	187	* Note: IMPMTU includes the leader.
	188	*/
	189	info = sc->acc_ifuba.ifu_r.ifrw_info;
	190	addr->iba = (u_short)info;
	191	addr->iwc = -(IMPMTU >> 1);
	192	#ifdef LOOPBACK
	193	addr->ocsr \|= OUT_BBACK;
	194	#endif
	195	addr->icsr =
	196	IN_MRDY \| ACC_IE \| IN_WEN \| ((info & 0x30000) >> 12) \| ACC_GO;
	197	return (1);
	198	}
	199
	200	accinputreset(addr, unit)
	201	register struct accdevice *addr;
	202	register int unit;
	203	{
	204	register int i;
	205
	206	addr->icsr = ACC_RESET; DELAY(5000);
	207	addr->icsr = IN_MRDY \| IN_WEN; /* close the relay */
	208	DELAY(10000);
	209	/* YECH!!! */
	210	for (i = 0; i < 500; i++) {
	211	if ((addr->icsr & IN_HRDY) \|\|
	212	(addr->icsr & (IN_RMR \| IN_IMPBSY)) == 0)
	213	return (1);
	214	addr->icsr = IN_MRDY \| IN_WEN; DELAY(10000);
	215	/* keep turning IN_RMR off */
	216	}
	217	printf("acc%d: imp doesn't respond, icsr=%b\n", unit,
	218	addr->icsr, ACC_INBITS);
	219	return (0);
	220	}
	221
	222	/*
	223	* Start output on an interface.
	224	*/
	225	accstart(dev)
	226	dev_t dev;
	227	{
	228	int unit = ACCUNIT(dev), info;
	229	register struct acc_softc *sc = &acc_softc[unit];
	230	register struct accdevice *addr;
	231	struct mbuf *m;
	232	u_short cmd;
	233
	234	if (sc->acc_ic->ic_oactive)
	235	goto restart;
	236
	237	/*
	238	* Not already active, deqeue a request and
	239	* map it onto the UNIBUS. If no more
	240	* requeusts, just return.
	241	*/
	242	IF_DEQUEUE(&sc->acc_if->if_snd, m);
	243	if (m == 0) {
	244	sc->acc_ic->ic_oactive = 0;
	245	return;
	246	}
	247	sc->acc_olen = if_wubaput(&sc->acc_ifuba, m);
	248
	249	restart:
	250	/*
	251	* Have request mapped to UNIBUS for
	252	* transmission; start the output.
	253	*/
	254	if (sc->acc_ifuba.ifu_flags & UBA_NEEDBDP)
	255	UBAPURGE(sc->acc_ifuba.ifu_uba, sc->acc_ifuba.ifu_w.ifrw_bdp);
	256	addr = (struct accdevice *)accinfo[unit]->ui_addr;
	257	info = sc->acc_ifuba.ifu_w.ifrw_info;
	258	addr->oba = (u_short)info;
	259	addr->owc = -((sc->acc_olen + 1) >> 1);
	260	cmd = ACC_IE \| OUT_ENLB \| ((info & 0x30000) >> 12) \| ACC_GO;
	261	#ifdef LOOPBACK
	262	cmd \|= OUT_BBACK;
	263	#endif
	264	addr->ocsr = cmd;
	265	sc->acc_ic->ic_oactive = 1;
	266	}
	267
	268	/*
	269	* Output interrupt handler.
	270	*/
	271	accxint(unit)
	272	int unit;
	273	{
	274	register struct acc_softc *sc = &acc_softc[unit];
	275	register struct accdevice *addr;
	276
	277	addr = (struct accdevice *)accinfo[unit]->ui_addr;
	278	if (sc->acc_ic->ic_oactive == 0) {
	279	printf("acc%d: stray xmit interrupt, csr=%b\n", unit,
	280	addr->ocsr, ACC_OUTBITS);
	281	return;
	282	}
	283	sc->acc_if->if_opackets++;
	284	sc->acc_ic->ic_oactive = 0;
	285	if (addr->ocsr & ACC_ERR) {
	286	printf("acc%d: output error, ocsr=%b, icsr=%b\n", unit,
	287	addr->ocsr, ACC_OUTBITS, addr->icsr, ACC_INBITS);
	288	sc->acc_if->if_oerrors++;
	289	}
	290	if (sc->acc_ifuba.ifu_xtofree) {
	291	m_freem(sc->acc_ifuba.ifu_xtofree);
	292	sc->acc_ifuba.ifu_xtofree = 0;
	293	}
	294	if (sc->acc_if->if_snd.ifq_head)
	295	accstart(unit);
	296	}
	297
	298	/*
	299	* Input interrupt handler
	300	*/
	301	accrint(unit)
	302	int unit;
	303	{
	304	register struct acc_softc *sc = &acc_softc[unit];
	305	register struct accdevice *addr;
	306	struct mbuf *m;
	307	int len, info;
	308
	309	addr = (struct accdevice *)accinfo[unit]->ui_addr;
	310	sc->acc_if->if_ipackets++;
	311
	312	/*
	313	* Purge BDP; flush message if error indicated.
	314	*/
	315	if (sc->acc_ifuba.ifu_flags & UBA_NEEDBDP)
	316	UBAPURGE(sc->acc_ifuba.ifu_uba, sc->acc_ifuba.ifu_r.ifrw_bdp);
	317	if (addr->icsr & ACC_ERR) {
	318	printf("acc%d: input error, csr=%b\n", unit,
	319	addr->icsr, ACC_INBITS);
	320	sc->acc_if->if_ierrors++;
	321	sc->acc_flush = 1;
	322	}
	323
	324	if (sc->acc_flush) {
	325	if (addr->icsr & IN_EOM)
	326	sc->acc_flush = 0;
	327	goto setup;
	328	}
	329	len = IMPMTU + (addr->iwc << 1);
	330	if (len < 0 \|\| len > IMPMTU) {
	331	printf("acc%d: bad length=%d\n", len);
	332	sc->acc_if->if_ierrors++;
	333	goto setup;
	334	}
	335
	336	/*
	337	* The last parameter is always 0 since using
	338	* trailers on the ARPAnet is insane.
	339	*/
	340	m = if_rubaget(&sc->acc_ifuba, len, 0);
	341	if (m == 0)
	342	goto setup;
	343	if ((addr->icsr & IN_EOM) == 0) {
	344	if (sc->acc_iq)
	345	m_cat(sc->acc_iq, m);
	346	else
	347	sc->acc_iq = m;
	348	goto setup;
	349	}
	350	if (sc->acc_iq) {
	351	m_cat(sc->acc_iq, m);
	352	m = sc->acc_iq;
	353	sc->acc_iq = 0;
	354	}
	355	impinput(unit, m);
	356
	357	setup:
	358	/*
	359	* Setup for next message.
	360	*/
	361	info = sc->acc_ifuba.ifu_r.ifrw_info;
	362	addr->iba = (u_short)info;
	363	addr->iwc = -(IMPMTU >> 1);
	364	addr->icsr =
	365	IN_MRDY \| ACC_IE \| IN_WEN \| ((info & 0x30000) >> 12) \| ACC_GO;
	366	}
	367	#endif