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

/*      if_acc.c        4.2     82/02/01        */

#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/accreg.h"
#include "../h/cpu.h"
#include "../h/mtpr.h"
#include "../h/vmmac.h"
#include "../net/in.h"
#include "../net/in_systm.h"
#include "../net/if.h"
#include "../net/if_imp.h"
#include "../net/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;

COUNT(ACCPROBE);
#ifdef lint
        br = 0; cvec = br; br = cvec;
        accrint(0); accxint(0);
#endif
        addr->acc_icsr = ACC_RESET;
        DELAY(500000);
        addr->acc_ocsr = ACC_RESET;
        DELAY(500000);

        addr->acc_ocsr = OUT_BBACK;
        DELAY(500000);
        addr->acc_owc = 0;
        addr->acc_ocsr = ACC_IE | ACC_GO;
        DELAY(500000);
        addr->acc_ocsr = 0;
        /* interrupt was for transmit, push back to receive vector */
        if (cvec && cvec != 0x200)
                cvec -= 4;
        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;

COUNT(ACCATTACH);
        if ((ifimp = (struct ifimpcb *)impattach(ui)) == 0)
                panic("accattach");             /* XXX */
        sc->acc_if = &ifimp->ifimp_if;
        ip = &ifimp->ifimp_impcb;
        sc->acc_ic = ip;
        ip->ic_init = accinit;
        ip->ic_start = accstart;
}

/*
 * 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;

COUNT(ACCRESET);
        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 reinitialize UNIBUS resources.
 */
accinit(unit)
        int unit;
{
        register struct acc_softc *sc = &acc_softc[unit];
        register struct uba_device *ui = accinfo[unit];
        register struct accdevice *addr;
        int x, info;

COUNT(ACCINIT);
        if (if_ubainit(&sc->acc_ifuba, ui->ui_ubanum,
              sizeof(struct imp_leader), (int)btop(IMP_MTU)) == 0) {
                printf("acc%d: can't initialize\n", unit);
                return;
        }
        addr = (struct accdevice *)ui->ui_addr;

        /*
         * Reset the imp interface.
         * the delays are totally guesses
         */
        x = spl5();
        addr->acc_icsr = ACC_RESET;
        DELAY(100);
        addr->acc_ocsr = ACC_RESET;
        DELAY(1000);
        addr->acc_ocsr = OUT_BBACK;     /* reset host master ready */
        DELAY(1000);
        addr->acc_ocsr = 0;
        addr->acc_icsr = IN_MRDY;       /* close the relay */
        splx(x);

        /* YECH!!! */
        while ((addr->acc_icsr & IN_HRDY) == 0 ||
               (addr->acc_icsr & (IN_RMR | IN_IMPBSY))) {
                /* keep turning IN_RMR off */
                addr->acc_icsr = IN_MRDY;
                sleep((caddr_t)&lbolt, PZERO);  /* ??? */
        }

        /*
         * 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).
         */
        x = spl5();
        info = sc->acc_ifuba.ifu_r.ifrw_info;
        addr->acc_iba = (u_short)info;
        addr->acc_iwc = -(sizeof(struct imp_leader) + IMP_MTU) >> 1;
        addr->acc_icsr =
                IN_MRDY | ACC_IE | IN_WEN | ((info & 0x30000) >> 12) | ACC_GO;
        splx(x);
}

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

COUNT(ACCSTART);
        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.
         * Purge any stale data from the BDP, and start the output.
         */
        UBAPURGE(sc->acc_ifuba.ifu_uba, sc->acc_ifuba.ifu_w.ifrw_bdp);
        addr = (struct accdevice *)ui->ui_addr;
        info = sc->acc_ifuba.ifu_w.ifrw_info;
        addr->acc_oba = (u_short)info;
        addr->acc_owc = -((sc->acc_olen + 1) >> 1);
        cmd = ACC_IE | OUT_ENLB | ((info & 0x30000) >> 12) | ACC_GO;
        addr->acc_ocsr = cmd;
        sc->acc_ic->ic_oactive = 1;
}

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

COUNT(ACCXINT);
        if (sc->acc_ic->ic_oactive == 0) {
                printf("acc%d: stray send interrupt\n", unit);
                return;
        }
        addr = (struct accdevice *)ui->ui_addr;
        sc->acc_if->if_opackets++;
        sc->acc_ic->ic_oactive = 0;
        if (addr->acc_ocsr & ACC_ERR) {
                printf("acc%d: send error, csr=%b\n", unit,
                        addr->acc_ocsr, ACC_OUTBITS);
                sc->acc_if->if_oerrors++;
        }
        if (sc->acc_if->if_snd.ifq_head == 0) {
                if (sc->acc_ifuba.ifu_xtofree) {
                        m_freem(sc->acc_ifuba.ifu_xtofree);
                        sc->acc_ifuba.ifu_xtofree = 0;
                }
                return;
        }
        accstart(unit);
}

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

COUNT(ACCRINT);
        sc->acc_if->if_ipackets++;

        /*
         * Purge BDP; flush message if error indicated.
         */
        UBAPURGE(sc->acc_ifuba.ifu_uba, sc->acc_ifuba.ifu_r.ifrw_bdp);
        addr = (struct accdevice *)accinfo[unit]->ui_addr;
        if (addr->acc_icsr & ACC_ERR) {
                printf("acc%d: recv error, csr=%b\n", unit,
                    addr->acc_icsr, ACC_INBITS);
                sc->acc_if->if_ierrors++;
                sc->acc_flush = 1;
        }

        if (sc->acc_flush) {
                if (addr->acc_icsr & IN_EOM)
                        sc->acc_flush = 0;
                goto setup;
        }
        len = sizeof(struct imp_leader) + (addr->acc_iwc << 1);

        /*
         * 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->acc_icsr & IN_EOM) == 0) {
                if (sc->acc_iq)
                        m_cat(sc->acc_iq, m);
                else
                        sc->acc_iq = m;
                goto setup;
        }
        /* adjust message length for padding. */
        m->m_len -= 2;
        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->acc_iba = (u_short)info;
        addr->acc_iwc = - (sizeof(struct imp_leader) + IMP_MTU) >> 1;
        addr->acc_icsr =
                IN_MRDY | ACC_IE | IN_WEN | ((info & 0x30000) >> 12) | ACC_GO;
}
#endif