if_ns.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

		
		if (interrupts & ENISR_TX) {
			nsxint(sc);
		}
		else if (interrupts & ENISR_COUNTERS) {
			/*
			 * XXX - We really should be storing statistics 
			 * about the interface.  For now we just drop them.
			 */

			/* reading resets the counters! */
			(void) inb_p(port + EN0_COUNTER0);   	/* frame */
		  	(void) inb_p(port + EN0_COUNTER1);	/* crc */
		  	(void) inb_p(port + EN0_COUNTER2);	/* miss */

			DEBUGF(printf("%s%d: acked counter interrupt.\n",
				      sc->sc_name, sc->sc_unit));

			outb_p(port + EN0_ISR, ENISR_COUNTERS);	/* ack intr */
		}
		
		if (interrupts & ENISR_TX_ERR) {
			DEBUGF(printf("acking transmit error\n"));
			outb_p(port + EN0_ISR, ENISR_TX_ERR);	/* ack intr */
		}

		outb_p(port + E8390_CMD, E8390_NODMA+E8390_PAGE0+E8390_START);
	}

	DEBUGF({
		if (interrupts) {
			printf("%s%d: unknown interrupt 0x%x",
			       sc->sc_name, sc->sc_unit, interrupts);
			outb_p(port + E8390_CMD,
			       E8390_NODMA+E8390_PAGE0+E8390_START);
			outb_p(port + EN0_ISR, 0xff);	/* ack all intrs */
		}
	})
}

/*
 * Process a transmit interrupt.
 */
void
nsxint(sc)
	struct nssoftc *sc;
{
	int port = sc->sc_port, status;
	struct ifnet *ifp = &sc->sc_if;

	status = inb(port + EN0_TSR);
	outb_p(port + EN0_ISR, ENISR_TX);	/* ack intr */

	sc->sc_txing = 0;
	sc->sc_timer = 0;
	sc->sc_oactive = 0;

	if (sc->sc_pingpong) {
		if (sc->sc_tx1 < 0) {
			if (sc->sc_lasttx != 1 && sc->sc_lasttx != -1)
				printf("%s%d: bogus last_tx_buffer %d,"
				       "tx1 = %d\n",
				       sc->sc_name, sc->sc_unit,
				       sc->sc_lasttx, sc->sc_tx1);
			sc->sc_tx1 = 0;
			if (sc->sc_tx2 > 0) {
				nsxmit(sc, sc->sc_tx2, sc->sc_txstrtpg + 6);
				sc->sc_tx2 = -1;
				sc->sc_lasttx = 2;
			} else
				sc->sc_lasttx = 20;
		} else if (sc->sc_tx2 < 0) {
			if (sc->sc_lasttx != 2 && sc->sc_lasttx != -2)
				printf("%s%d: bogus last_tx_buffer %d,"
				       "tx2 = %d\n",
				       sc->sc_name, sc->sc_unit,
				       sc->sc_lasttx, sc->sc_tx2);
			sc->sc_tx2 = 0;
			if (sc->sc_tx1 > 0) {
				nsxmit(sc, sc->sc_tx1, sc->sc_txstrtpg);
				sc->sc_tx1 = -1;
				sc->sc_lasttx = 1;
			} else
				sc->sc_lasttx = 10;
		} else
			printf("%s%d: unexpected TX-done interrupt, "
			       "lasttx = %d\n",
			       sc->sc_name, sc->sc_unit, sc->sc_lasttx);
	}
	/*
	 * Update stats.
	 */
	if (status & ENTSR_COL) {
		if (status & ENTSR_ABT)
			ifp->if_collisions += 16;
		else
			ifp->if_collisions += inb(port + EN0_NCR);
	}
	if (status & ENTSR_PTX) {
		DEBUGF(printf("sent: %s%d\n", sc->sc_name, sc->sc_unit));
		ifp->if_opackets++;
	} else
		ifp->if_oerrors++;

	/*
	 * Start output on interface.
	 */
	nsstart(sc);
}

/*
 * Process a receive interrupt.
 */
void
nsrint(sc)
	struct nssoftc *sc;
{
	int port = sc->sc_port;
	int rxing_page, this_frame, next_frame, current_offset;
	int rx_pkt_count = 0;
	int num_rx_pages = sc->sc_stoppg - sc->sc_rxstrtpg;
	struct nspkthdr rx_frame;
	struct ifnet *ifp = &sc->sc_if;

	while (++rx_pkt_count < 10) {
		int pkt_len;

		/*
		 * Get the rx page (incoming packet pointer).
		 */
		outb_p(port + E8390_CMD, E8390_NODMA+E8390_PAGE1);
		rxing_page = inb_p(port + EN1_CURPAG);
		outb_p(port + E8390_CMD, E8390_NODMA+E8390_PAGE0);

		/*
		 * Remove one frame from the ring.
		 * Boundary is always a page behind.
		 */
		this_frame = inb_p(port + EN0_BOUNDARY) + 1;
		if (this_frame >= sc->sc_stoppg)
			this_frame = sc->sc_rxstrtpg;

		DEBUGF({
			if (this_frame != sc->sc_curpg)
				printf("%s%d: mismatched read page pointers "
				       "%x vs %x\n",
				       sc->sc_name, sc->sc_unit,
				       this_frame, sc->sc_curpg);
		});

		if (this_frame == rxing_page) {
		  	DEBUGF(printf("this_frame = rxing_page!\n"));
			break;
		}

		current_offset = this_frame << 8;
		(*sc->sc_input)(sc, sizeof(rx_frame), (char *)&rx_frame,
				current_offset);

		pkt_len = rx_frame.count - sizeof(rx_frame);

		next_frame = this_frame + 1 + ((pkt_len + 4) >> 8);

		if (rx_frame.next != next_frame
		    && rx_frame.next != next_frame + 1
		    && rx_frame.next != next_frame - num_rx_pages
		    && rx_frame.next != next_frame + 1 - num_rx_pages) {
			sc->sc_curpg = rxing_page;
			outb(port + EN0_BOUNDARY, sc->sc_curpg - 1);
			ifp->if_ierrors++;
			DEBUGF(printf("INPUT ERROR?\n"));
			continue;
		}
		if (pkt_len < 60 || pkt_len > 1518) {
			ifp->if_ierrors++;
			DEBUGF(printf("%s%d: bad packet length %d\n",
				      sc->sc_name, sc->sc_unit, pkt_len));
		} else if ((rx_frame.status & 0x0f) == ENRSR_RXOK) {
			ipc_kmsg_t kmsg;

			kmsg = net_kmsg_get();
			if (kmsg == 0) {
				DEBUGF(printf("%s%d: dropped packet\n",
					      sc->sc_name, sc->sc_unit));
				ifp->if_rcvdrops++;
			} else {
				int len, off;
				struct ether_header *eh;
				struct packet_header *pkt;

				ifp->if_ipackets++;
				off = current_offset + sizeof(rx_frame);
				eh = ((struct ether_header *)
				      (&net_kmsg(kmsg)->header[0]));
				(*sc->sc_input)(sc,
						sizeof(struct ether_header),
						(char *)eh, off);
				off += sizeof(struct ether_header);
				len = pkt_len - sizeof(struct ether_header);

				DEBUGF(printf("rcv: %s%d: %x:%x:%x:%x:%x:%x, "
					      "len %d, type 0x%x\n",
					      sc->sc_name, sc->sc_unit,
					      eh->ether_shost[0],
					      eh->ether_shost[1],
					      eh->ether_shost[2],
					      eh->ether_shost[3],
					      eh->ether_shost[4],
					      eh->ether_shost[5],
					      len, eh->ether_type));

				pkt = ((struct packet_header *)
				       (&net_kmsg(kmsg)->packet[0]));
				(*sc->sc_input)(sc, len, (char *)(pkt+1), off);
				pkt->type = eh->ether_type;
				pkt->length = len+sizeof(struct packet_header);
				net_packet(ifp, kmsg, pkt->length,
					   ethernet_priority(kmsg));
			}
		} else {
			DEBUGF(printf("%s%d: bogus packet: "
				      "status=0x%x nxpg=0x%x size=%d\n",
				      sc->sc_name, sc->sc_unit,
				      rx_frame.status, rx_frame.next,
				      rx_frame.count));
			ifp->if_ierrors++;
		}
		next_frame = rx_frame.next;
		if (next_frame >= sc->sc_stoppg) {
			DEBUGF(printf("%s%d: next frame inconsistency, 0x%x\n",
				      sc->sc_name, sc->sc_unit, next_frame));
			next_frame = sc->sc_rxstrtpg;
		}
		sc->sc_curpg = next_frame;
		outb(port + EN0_BOUNDARY, next_frame - 1);
	}

	/*
	 * Bug alert!  Reset ENISR_OVER to avoid spurious overruns!
	 */
	outb_p(port + EN0_ISR, ENISR_RX+ENISR_RX_ERR+ENISR_OVER);
}

/*
 * Handle a receive overrun condition.
 *
 * XXX - this needs to be gone over in light of the NS documentation.
 */
void
nsrxoverrun(sc)
	struct nssoftc *sc;
{
	int port = sc->sc_port, i;
	extern unsigned delaycount;

	printf("%s%d: receive overrun\n", sc->sc_name, sc->sc_unit);

	/*
	 * We should already be stopped and in page0, but just to be sure...
	 */
	outb_p(port + E8390_CMD, E8390_NODMA+E8390_PAGE0+E8390_STOP);

	/*
	 * Clear remote byte counter registers.
	 */
	outb_p(port + EN0_RCNTLO, 0);
	outb_p(port + EN0_RCNTHI, 0);

	/*
	 * Wait for reset to complete.
	 */
	for (i = delaycount*2; i && !(inb_p(port+EN0_ISR) & ENISR_RESET); i--)
		;
	if (i == 0) {
		printf("%s%d: reset did not complete at overrun\n",
		       sc->sc_name, sc->sc_unit);
		nsinit(sc);
		return;
	}
	/*
	 * Disable transmitter.
	 */
	outb_p(port + EN0_TXCR, E8390_TXOFF);

	/*
	 * Remove packets.
	 */
	nsrint(sc);

	outb_p(port + EN0_ISR, 0xff);
	outb_p(port + E8390_CMD, E8390_NODMA+E8390_PAGE0+E8390_START);
	outb_p(port + EN0_TXCR, E8390_TXCONFIG);
}

/*
 * Trigger a transmit start.
 */
void
nsxmit(sc, length, start_page)
	struct nssoftc *sc;
	unsigned length;
	int start_page;
{
	int port = sc->sc_port;

	sc->sc_txing = 1;
	outb_p(port, E8390_NODMA+E8390_PAGE0);
	if (inb_p(port) & E8390_TRANS) {
		printf("%s%d: nsxmit() called with the transmitter busy\n",
		       sc->sc_name, sc->sc_unit);
		return;
	}
	outb_p(port + EN0_TCNTLO, length & 0xff);
	outb_p(port + EN0_TCNTHI, (length >> 8) & 0xff);
	outb_p(port + EN0_TPSR, start_page);
	outb_p(port, E8390_NODMA+E8390_TRANS+E8390_START);
	sc->sc_timer = 4;
}

#endif	/* NUL > 0 || NWD > 0 */