/*
* Start output on interface. Get another datagram
* to send from the interface queue and map it to
* the interface before starting output.
*
* Must be called at spl 5
*/
void
dmcstart(struct ifnet *ifp)
{
struct dmc_softc *sc = ifp->if_softc;
struct mbuf *m;
struct dmcbufs *rp;
int n;
/*
* Dequeue up to NXMT requests and map them to the UNIBUS.
* If no more requests, or no dmc buffers available, just return.
*/
n = 0;
for (rp = &sc->sc_xbufs[0]; rp < &sc->sc_xbufs[NXMT]; rp++ ) {
/* find an available buffer */
if ((rp->flags & DBUF_DMCS) == 0) {
IFQ_DEQUEUE(&sc->sc_if.if_snd, m);
if (m == 0)
return;
/* mark it dmcs */
rp->flags |= (DBUF_DMCS);
/*
* Have request mapped to UNIBUS for transmission
* and start the output.
*/
rp->cc = if_ubaput(&sc->sc_ifuba, &sc->sc_ifw[n], m);
rp->cc &= DMC_CCOUNT;
if (++sc->sc_oused == 1)
sc->sc_if.if_timer = dmc_timeout;
dmcload(sc, DMC_WRITE, rp->ubinfo,
rp->cc | ((rp->ubinfo>>2)&DMC_XMEM));
}
n++;
}
/*
* Setup output on interface.
* Get another datagram to send off of the interface queue,
* and map it to the interface before starting the output.
* Must be called from ipl >= our interrupt level.
*/
void
destart(struct ifnet *ifp)
{
struct de_softc *sc = ifp->if_softc;
struct de_cdata *dc;
struct de_ring *rp;
struct mbuf *m;
int nxmit, len;
/*
* the following test is necessary, since
* the code is not reentrant and we have
* multiple transmission buffers.
*/
if (sc->sc_if.if_flags & IFF_OACTIVE)
return;
dc = sc->sc_dedata;
for (nxmit = sc->sc_nxmit; nxmit < NXMT; nxmit++) {
IFQ_DEQUEUE(&ifp->if_snd, m);
if (m == 0)
break;
rp = &dc->dc_xrent[sc->sc_xfree];
if (rp->r_flags & XFLG_OWN)
panic("deuna xmit in progress");
#if NBPFILTER > 0
if (ifp->if_bpf)
bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT);
#endif
len = if_ubaput(&sc->sc_ifuba, &sc->sc_ifw[sc->sc_xfree], m);
rp->r_slen = len;
rp->r_tdrerr = 0;
rp->r_flags = XFLG_STP|XFLG_ENP|XFLG_OWN;
sc->sc_xfree++;
if (sc->sc_xfree == NXMT)
sc->sc_xfree = 0;
}
if (sc->sc_nxmit != nxmit) {
sc->sc_nxmit = nxmit;
if (ifp->if_flags & IFF_RUNNING)
DE_WLOW(PCSR0_INTE|CMD_PDMD);
}
}
