8390.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

    struct ei_device *ei_local = (struct ei_device *) dev->priv;
    
    outb_p(ENISR_TX, e8390_base + EN0_ISR); /* Ack intr. */

#ifdef EI_PINGPONG

    /*
     * There are two Tx buffers, see which one finished, and trigger
     * the send of another one if it exists.
     */
    ei_local->txqueue--;
    if (ei_local->tx1 < 0) {
	if (ei_local->lasttx != 1 && ei_local->lasttx != -1)
		printk("%s: bogus last_tx_buffer %d, tx1=%d.\n",
			   ei_local->name, ei_local->lasttx, ei_local->tx1);
	ei_local->tx1 = 0;
	dev->tbusy = 0;
	if (ei_local->tx2 > 0) {
		ei_local->txing = 1;
		NS8390_trigger_send(dev, ei_local->tx2, ei_local->tx_start_page + 6);
		dev->trans_start = jiffies;
		ei_local->tx2 = -1,
		ei_local->lasttx = 2;
	} else
		ei_local->lasttx = 20, ei_local->txing = 0;
    } else if (ei_local->tx2 < 0) {
	if (ei_local->lasttx != 2  &&  ei_local->lasttx != -2)
		printk("%s: bogus last_tx_buffer %d, tx2=%d.\n",
			   ei_local->name, ei_local->lasttx, ei_local->tx2);
	ei_local->tx2 = 0;
	dev->tbusy = 0;
	if (ei_local->tx1 > 0) {
		ei_local->txing = 1;
		NS8390_trigger_send(dev, ei_local->tx1, ei_local->tx_start_page);
		dev->trans_start = jiffies;
		ei_local->tx1 = -1;
		ei_local->lasttx = 1;
	} else
		ei_local->lasttx = 10, ei_local->txing = 0;
    } else
	printk("%s: unexpected TX-done interrupt, lasttx=%d.\n",
		   dev->name, ei_local->lasttx);

#else	/* EI_PINGPONG */
    /*
     *  Single Tx buffer: mark it free so another packet can be loaded.
     */
    ei_local->txing = 0;
    dev->tbusy = 0;
#endif

    /* Minimize Tx latency: update the statistics after we restart TXing. */
    if (status & ENTSR_COL)
	ei_local->stat.collisions++;
    if (status & ENTSR_PTX)
	ei_local->stat.tx_packets++;
    else {
	ei_local->stat.tx_errors++;
	if (status & ENTSR_ABT) ei_local->stat.tx_aborted_errors++;
	if (status & ENTSR_CRS) ei_local->stat.tx_carrier_errors++;
	if (status & ENTSR_FU)  ei_local->stat.tx_fifo_errors++;
	if (status & ENTSR_CDH) ei_local->stat.tx_heartbeat_errors++;
	if (status & ENTSR_OWC) ei_local->stat.tx_window_errors++;
    }

    mark_bh (NET_BH);
}

/* We have a good packet(s), get it/them out of the buffers. */

static void ei_receive(struct device *dev)
{
    int e8390_base = dev->base_addr;
    struct ei_device *ei_local = (struct ei_device *) dev->priv;
    unsigned char rxing_page, this_frame, next_frame;
    unsigned short current_offset;
    int rx_pkt_count = 0;
    struct e8390_pkt_hdr rx_frame;
    int num_rx_pages = ei_local->stop_page-ei_local->rx_start_page;
    
    while (++rx_pkt_count < 10) {
		int pkt_len;
		
		/* Get the rx page (incoming packet pointer). */
		outb_p(E8390_NODMA+E8390_PAGE1, e8390_base + E8390_CMD);
		rxing_page = inb_p(e8390_base + EN1_CURPAG);
		outb_p(E8390_NODMA+E8390_PAGE0, e8390_base + E8390_CMD);
		
		/* Remove one frame from the ring.  Boundary is always a page behind. */
		this_frame = inb_p(e8390_base + EN0_BOUNDARY) + 1;
		if (this_frame >= ei_local->stop_page)
			this_frame = ei_local->rx_start_page;
		
		/* Someday we'll omit the previous, iff we never get this message.
		   (There is at least one clone claimed to have a problem.)  */
		if (ei_debug > 0  &&  this_frame != ei_local->current_page)
			printk("%s: mismatched read page pointers %2x vs %2x.\n",
				   dev->name, this_frame, ei_local->current_page);
		
		if (this_frame == rxing_page)	/* Read all the frames? */
			break;				/* Done for now */
		
		current_offset = this_frame << 8;
		ei_get_8390_hdr(dev, &rx_frame, this_frame);
		
		pkt_len = rx_frame.count - sizeof(struct e8390_pkt_hdr);
		
		next_frame = this_frame + 1 + ((pkt_len+4)>>8);
		
		/* Check for bogosity warned by 3c503 book: the status byte is never
		   written.  This happened a lot during testing! This code should be
		   cleaned up someday. */
		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) {
			ei_local->current_page = rxing_page;
			outb(ei_local->current_page-1, e8390_base+EN0_BOUNDARY);
			ei_local->stat.rx_errors++;
			continue;
		}

		if (pkt_len < 60  ||  pkt_len > 1518) {
			if (ei_debug)
				printk("%s: bogus packet size: %d, status=%#2x nxpg=%#2x.\n",
					   dev->name, rx_frame.count, rx_frame.status,
					   rx_frame.next);
			ei_local->stat.rx_errors++;
		} else if ((rx_frame.status & 0x0F) == ENRSR_RXOK) {
			struct sk_buff *skb;
			
			skb = dev_alloc_skb(pkt_len+2);
			if (skb == NULL) {
				if (ei_debug > 1)
					printk("%s: Couldn't allocate a sk_buff of size %d.\n",
						   dev->name, pkt_len);
				ei_local->stat.rx_dropped++;
				break;
			} else {
				skb_reserve(skb,2);	/* IP headers on 16 byte boundaries */
				skb->dev = dev;
				skb_put(skb, pkt_len);	/* Make room */
				ei_block_input(dev, pkt_len, skb, current_offset + sizeof(rx_frame));
				skb->protocol=eth_type_trans(skb,dev);
				netif_rx(skb);
				ei_local->stat.rx_packets++;
			}
		} else {
			int errs = rx_frame.status;
			if (ei_debug)
				printk("%s: bogus packet: status=%#2x nxpg=%#2x size=%d\n",
					   dev->name, rx_frame.status, rx_frame.next,
					   rx_frame.count);
			if (errs & ENRSR_FO)
				ei_local->stat.rx_fifo_errors++;
		}
		next_frame = rx_frame.next;
		
		/* This _should_ never happen: it's here for avoiding bad clones. */
		if (next_frame >= ei_local->stop_page) {
			printk("%s: next frame inconsistency, %#2x\n", dev->name,
				   next_frame);
			next_frame = ei_local->rx_start_page;
		}
		ei_local->current_page = next_frame;
		outb_p(next_frame-1, e8390_base+EN0_BOUNDARY);
    }

    /* We used to also ack ENISR_OVER here, but that would sometimes mask
    a real overrun, leaving the 8390 in a stopped state with rec'vr off. */
    outb_p(ENISR_RX+ENISR_RX_ERR, e8390_base+EN0_ISR);
    return;
}

/* 
 * We have a receiver overrun: we have to kick the 8390 to get it started
 * again. Problem is that you have to kick it exactly as NS prescribes in
 * the updated datasheets, or "the NIC may act in an unpredictable manner."
 * This includes causing "the NIC to defer indefinitely when it is stopped
 * on a busy network."  Ugh.
 */
static void ei_rx_overrun(struct device *dev)
{
    int e8390_base = dev->base_addr;
    unsigned long wait_start_time;
    unsigned char was_txing, must_resend = 0;
    struct ei_device *ei_local = (struct ei_device *) dev->priv;
    
    /*
     * Record whether a Tx was in progress and then issue the
     * stop command.
     */
    was_txing = inb_p(e8390_base+E8390_CMD) & E8390_TRANS;
    outb_p(E8390_NODMA+E8390_PAGE0+E8390_STOP, e8390_base+E8390_CMD);
    
    if (ei_debug > 1)
	printk("%s: Receiver overrun.\n", dev->name);
    ei_local->stat.rx_over_errors++;
    
    /* 
     * Wait a full Tx time (1.2ms) + some guard time, NS says 1.6ms total.
     * Early datasheets said to poll the reset bit, but now they say that
     * it "is not a reliable indicator and subsequently should be ignored."
     * We wait at least 10ms.
     */
    wait_start_time = jiffies;
    while (jiffies - wait_start_time <= 1*HZ/100)
	barrier();

    /*
     * Reset RBCR[01] back to zero as per magic incantation.
     */
    outb_p(0x00, e8390_base+EN0_RCNTLO);
    outb_p(0x00, e8390_base+EN0_RCNTHI);

    /*
     * See if any Tx was interrupted or not. According to NS, this
     * step is vital, and skipping it will cause no end of havoc.
     */
    if (was_txing) { 
	unsigned char tx_completed = inb_p(e8390_base+EN0_ISR) & (ENISR_TX+ENISR_TX_ERR);
	if (!tx_completed) must_resend = 1;
    }

    /*
     * Have to enter loopback mode and then restart the NIC before
     * you are allowed to slurp packets up off the ring.
     */
    outb_p(E8390_TXOFF, e8390_base + EN0_TXCR);
    outb_p(E8390_NODMA + E8390_PAGE0 + E8390_START, e8390_base + E8390_CMD);

    /*
     * Clear the Rx ring of all the debris, and ack the interrupt.
     */
    ei_receive(dev);
    outb_p(ENISR_OVER, e8390_base+EN0_ISR);

    /*
     * Leave loopback mode, and resend any packet that got stopped.
     */
    outb_p(E8390_TXCONFIG, e8390_base + EN0_TXCR); 
    if (must_resend)
    	outb_p(E8390_NODMA + E8390_PAGE0 + E8390_START + E8390_TRANS, e8390_base + E8390_CMD);
	
}

static struct enet_statistics *get_stats(struct device *dev)
{
    short ioaddr = dev->base_addr;
    struct ei_device *ei_local = (struct ei_device *) dev->priv;
    
    /* If the card is stopped, just return the present stats. */
    if (dev->start == 0) return &ei_local->stat;

    /* Read the counter registers, assuming we are in page 0. */
    ei_local->stat.rx_frame_errors += inb_p(ioaddr + EN0_COUNTER0);
    ei_local->stat.rx_crc_errors   += inb_p(ioaddr + EN0_COUNTER1);
    ei_local->stat.rx_missed_errors+= inb_p(ioaddr + EN0_COUNTER2);
    
    return &ei_local->stat;
}

/*
 *	Set or clear the multicast filter for this adaptor.
 */
 
static void set_multicast_list(struct device *dev)
{
	short ioaddr = dev->base_addr;
    
	if(dev->flags&IFF_PROMISC)
	{
		outb_p(E8390_RXCONFIG | 0x18, ioaddr + EN0_RXCR);
	}
	else if((dev->flags&IFF_ALLMULTI)||dev->mc_list)
	{
		/* The multicast-accept list is initialized to accept-all, and we
		   rely on higher-level filtering for now. */
		outb_p(E8390_RXCONFIG | 0x08, ioaddr + EN0_RXCR);
	} 
	else
		outb_p(E8390_RXCONFIG, ioaddr + EN0_RXCR);
}

/* Initialize the rest of the 8390 device structure. */
int ethdev_init(struct device *dev)
{
    if (ei_debug > 1)
		printk(version);
    
    if (dev->priv == NULL) {
		struct ei_device *ei_local;
		
		dev->priv = kmalloc(sizeof(struct ei_device), GFP_KERNEL);
		if (dev->priv == NULL)
			return -ENOMEM;
		memset(dev->priv, 0, sizeof(struct ei_device));
		ei_local = (struct ei_device *)dev->priv;
    }
    
    dev->hard_start_xmit = &ei_start_xmit;
    dev->get_stats	= get_stats;
    dev->set_multicast_list = &set_multicast_list;

    ether_setup(dev);
        
    return 0;
}


/* This page of functions should be 8390 generic */
/* Follow National Semi's recommendations for initializing the "NIC". */
void NS8390_init(struct device *dev, int startp)
{
    int e8390_base = dev->base_addr;
    struct ei_device *ei_local = (struct ei_device *) dev->priv;
    int i;
    int endcfg = ei_local->word16 ? (0x48 | ENDCFG_WTS) : 0x48;
    unsigned long flags;
    
    /* Follow National Semi's recommendations for initing the DP83902. */
    outb_p(E8390_NODMA+E8390_PAGE0+E8390_STOP, e8390_base); /* 0x21 */
    outb_p(endcfg, e8390_base + EN0_DCFG);	/* 0x48 or 0x49 */
    /* Clear the remote byte count registers. */
    outb_p(0x00,  e8390_base + EN0_RCNTLO);
    outb_p(0x00,  e8390_base + EN0_RCNTHI);
    /* Set to monitor and loopback mode -- this is vital!. */
    outb_p(E8390_RXOFF, e8390_base + EN0_RXCR); /* 0x20 */
    outb_p(E8390_TXOFF, e8390_base + EN0_TXCR); /* 0x02 */
    /* Set the transmit page and receive ring. */
    outb_p(ei_local->tx_start_page,	 e8390_base + EN0_TPSR);
    ei_local->tx1 = ei_local->tx2 = 0;
    outb_p(ei_local->rx_start_page,	 e8390_base + EN0_STARTPG);
    outb_p(ei_local->stop_page-1, e8390_base + EN0_BOUNDARY); /* 3c503 says 0x3f,NS0x26*/
    ei_local->current_page = ei_local->rx_start_page;		/* assert boundary+1 */
    outb_p(ei_local->stop_page,	  e8390_base + EN0_STOPPG);
    /* Clear the pending interrupts and mask. */
    outb_p(0xFF, e8390_base + EN0_ISR);
    outb_p(0x00,  e8390_base + EN0_IMR);
    
    /* Copy the station address into the DS8390 registers,
       and set the multicast hash bitmap to receive all multicasts. */
    save_flags(flags);
    cli();
    outb_p(E8390_NODMA + E8390_PAGE1 + E8390_STOP, e8390_base); /* 0x61 */
    for(i = 0; i < 6; i++) {
		outb_p(dev->dev_addr[i], e8390_base + EN1_PHYS + i);
    }
    /* Initialize the multicast list to accept-all.  If we enable multicast
       the higher levels can do the filtering. */
    for(i = 0; i < 8; i++)
		outb_p(0xff, e8390_base + EN1_MULT + i);
    
    outb_p(ei_local->rx_start_page,	 e8390_base + EN1_CURPAG);
    outb_p(E8390_NODMA+E8390_PAGE0+E8390_STOP, e8390_base);
    restore_flags(flags);
    dev->tbusy = 0;
    dev->interrupt = 0;
    ei_local->tx1 = ei_local->tx2 = 0;
    ei_local->txing = 0;
    if (startp) {
		outb_p(0xff,  e8390_base + EN0_ISR);
		outb_p(ENISR_ALL,  e8390_base + EN0_IMR);
		outb_p(E8390_NODMA+E8390_PAGE0+E8390_START, e8390_base);
		outb_p(E8390_TXCONFIG, e8390_base + EN0_TXCR); /* xmit on. */
		/* 3c503 TechMan says rxconfig only after the NIC is started. */
		outb_p(E8390_RXCONFIG,	e8390_base + EN0_RXCR); /* rx on,  */
		dev->set_multicast_list(dev);		/* Get the multicast status right if this
							   was a reset. */
    }
    return;
}

/* Trigger a transmit start, assuming the length is valid. */
static void NS8390_trigger_send(struct device *dev, unsigned int length,
								int start_page)
{
    int e8390_base = dev->base_addr;
    
    outb_p(E8390_NODMA+E8390_PAGE0, e8390_base);
    
    if (inb_p(e8390_base) & E8390_TRANS) {
		printk("%s: trigger_send() called with the transmitter busy.\n",
			   dev->name);
		return;
    }
    outb_p(length & 0xff, e8390_base + EN0_TCNTLO);
    outb_p(length >> 8, e8390_base + EN0_TCNTHI);
    outb_p(start_page, e8390_base + EN0_TPSR);
    outb_p(E8390_NODMA+E8390_TRANS+E8390_START, e8390_base);
    return;
}

#ifdef MODULE

int init_module(void)
{
     return 0;
}

void
cleanup_module(void)
{
}
#endif /* MODULE */

/*
 * Local variables:
 *  compile-command: "gcc -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -m486 -c 8390.c"
 *  version-control: t
 *  kept-new-versions: 5
 *  c-indent-level: 4
 *  tab-width: 4
 * End:
 */