lance.c

powerpc内核mpc8241linux系统下net驱动程序

	int entry;
	unsigned long flags;

	/* Transmitter timeout, serious problems. */
	if (dev->tbusy) {
		int tickssofar = jiffies - dev->trans_start;
		if (tickssofar < 20)
			return 1;
		outw(0, ioaddr+LANCE_ADDR);
		printk("%s: transmit timed out, status %4.4x, resetting.\n",
			   dev->name, inw(ioaddr+LANCE_DATA));
		outw(0x0004, ioaddr+LANCE_DATA);
		lp->stats.tx_errors++;
#ifndef final_version
		{
			int i;
			printk(" Ring data dump: dirty_tx %d cur_tx %d%s cur_rx %d.",
				   lp->dirty_tx, lp->cur_tx, lp->tx_full ? " (full)" : "",
				   lp->cur_rx);
			for (i = 0 ; i < RX_RING_SIZE; i++)
				printk("%s %08x %04x %04x", i & 0x3 ? "" : "\n ",
					   lp->rx_ring[i].base, -lp->rx_ring[i].buf_length,
					   lp->rx_ring[i].msg_length);
			for (i = 0 ; i < TX_RING_SIZE; i++)
				printk("%s %08x %04x %04x", i & 0x3 ? "" : "\n ",
					   lp->tx_ring[i].base, -lp->tx_ring[i].length,
					   lp->tx_ring[i].misc);
			printk("\n");
		}
#endif
		lance_restart(dev, 0x0043, 1);

		dev->tbusy=0;
		dev->trans_start = jiffies;

		return 0;
	}

	if (lance_debug > 3) {
		outw(0x0000, ioaddr+LANCE_ADDR);
		printk("%s: lance_start_xmit() called, csr0 %4.4x.\n", dev->name,
			   inw(ioaddr+LANCE_DATA));
		outw(0x0000, ioaddr+LANCE_DATA);
	}

	/* Block a timer-based transmit from overlapping.  This could better be
	   done with atomic_swap(1, dev->tbusy), but set_bit() works as well. */
	if (test_and_set_bit(0, (void*)&dev->tbusy) != 0) {
		printk("%s: Transmitter access conflict.\n", dev->name);
		return 1;
	}

	if (test_and_set_bit(0, (void*)&lp->lock) != 0) {
		if (lance_debug > 0)
			printk("%s: tx queue lock!.\n", dev->name);
		/* don't clear dev->tbusy flag. */
		return 1;
	}

	/* Fill in a Tx ring entry */

	/* Mask to ring buffer boundary. */
	entry = lp->cur_tx & TX_RING_MOD_MASK;

	/* Caution: the write order is important here, set the base address
	   with the "ownership" bits last. */

	/* The old LANCE chips doesn't automatically pad buffers to min. size. */
	if (chip_table[lp->chip_version].flags & LANCE_MUST_PAD) {
		lp->tx_ring[entry].length =
			-(ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN);
	} else
		lp->tx_ring[entry].length = -skb->len;

	lp->tx_ring[entry].misc = 0x0000;

	/* If any part of this buffer is >16M we must copy it to a low-memory
	   buffer. */
	if ((u32)virt_to_bus(skb->data) + skb->len > 0x01000000) {
		if (lance_debug > 5)
			printk("%s: bouncing a high-memory packet (%#x).\n",
				   dev->name, (u32)virt_to_bus(skb->data));
		memcpy(&lp->tx_bounce_buffs[entry], skb->data, skb->len);
		lp->tx_ring[entry].base =
			((u32)virt_to_bus((lp->tx_bounce_buffs + entry)) & 0xffffff) | 0x83000000;
		dev_kfree_skb(skb);
	} else {
		lp->tx_skbuff[entry] = skb;
		lp->tx_ring[entry].base = ((u32)virt_to_bus(skb->data) & 0xffffff) | 0x83000000;
	}
	lp->cur_tx++;
	lp->stats.tx_bytes += skb->len;

	/* Trigger an immediate send poll. */
	outw(0x0000, ioaddr+LANCE_ADDR);
	outw(0x0048, ioaddr+LANCE_DATA);

	dev->trans_start = jiffies;

	save_flags(flags);
	cli();
	lp->lock = 0;
	if (lp->tx_ring[(entry+1) & TX_RING_MOD_MASK].base == 0)
		dev->tbusy=0;
	else
		lp->tx_full = 1;
	restore_flags(flags);

	return 0;
}

/* The LANCE interrupt handler. */
static void
lance_interrupt(int irq, void *dev_id, struct pt_regs * regs)
{
	struct device *dev = dev_id;
	struct lance_private *lp;
	int csr0, ioaddr, boguscnt=10;
	int must_restart;

	if (dev == NULL) {
		printk ("lance_interrupt(): irq %d for unknown device.\n", irq);
		return;
	}

	ioaddr = dev->base_addr;
	lp = (struct lance_private *)dev->priv;
	if (dev->interrupt)
		printk(KERN_WARNING "%s: Re-entering the interrupt handler.\n", dev->name);

	dev->interrupt = 1;

	outw(0x00, dev->base_addr + LANCE_ADDR);
	while ((csr0 = inw(dev->base_addr + LANCE_DATA)) & 0x8600
		   && --boguscnt >= 0) {
		/* Acknowledge all of the current interrupt sources ASAP. */
		outw(csr0 & ~0x004f, dev->base_addr + LANCE_DATA);

		must_restart = 0;

		if (lance_debug > 5)
			printk("%s: interrupt  csr0=%#2.2x new csr=%#2.2x.\n",
				   dev->name, csr0, inw(dev->base_addr + LANCE_DATA));

		if (csr0 & 0x0400)			/* Rx interrupt */
			lance_rx(dev);

		if (csr0 & 0x0200) {		/* Tx-done interrupt */
			int dirty_tx = lp->dirty_tx;

			while (dirty_tx < lp->cur_tx) {
				int entry = dirty_tx & TX_RING_MOD_MASK;
				int status = lp->tx_ring[entry].base;
			
				if (status < 0)
					break;			/* It still hasn't been Txed */

				lp->tx_ring[entry].base = 0;

				if (status & 0x40000000) {
					/* There was an major error, log it. */
					int err_status = lp->tx_ring[entry].misc;
					lp->stats.tx_errors++;
					if (err_status & 0x0400) lp->stats.tx_aborted_errors++;
					if (err_status & 0x0800) lp->stats.tx_carrier_errors++;
					if (err_status & 0x1000) lp->stats.tx_window_errors++;
					if (err_status & 0x4000) {
						/* Ackk!  On FIFO errors the Tx unit is turned off! */
						lp->stats.tx_fifo_errors++;
						/* Remove this verbosity later! */
						printk("%s: Tx FIFO error! Status %4.4x.\n",
							   dev->name, csr0);
						/* Restart the chip. */
						must_restart = 1;
					}
				} else {
					if (status & 0x18000000)
						lp->stats.collisions++;
					lp->stats.tx_packets++;
				}

				/* We must free the original skb if it's not a data-only copy
				   in the bounce buffer. */
				if (lp->tx_skbuff[entry]) {
					dev_kfree_skb(lp->tx_skbuff[entry]);
					lp->tx_skbuff[entry] = 0;
				}
				dirty_tx++;
			}

#ifndef final_version
			if (lp->cur_tx - dirty_tx >= TX_RING_SIZE) {
				printk("out-of-sync dirty pointer, %d vs. %d, full=%d.\n",
					   dirty_tx, lp->cur_tx, lp->tx_full);
				dirty_tx += TX_RING_SIZE;
			}
#endif

			if (lp->tx_full && dev->tbusy
				&& dirty_tx > lp->cur_tx - TX_RING_SIZE + 2) {
				/* The ring is no longer full, clear tbusy. */
				lp->tx_full = 0;
				dev->tbusy = 0;
				mark_bh(NET_BH);
			}

			lp->dirty_tx = dirty_tx;
		}

		/* Log misc errors. */
		if (csr0 & 0x4000) lp->stats.tx_errors++; /* Tx babble. */
		if (csr0 & 0x1000) lp->stats.rx_errors++; /* Missed a Rx frame. */
		if (csr0 & 0x0800) {
			printk("%s: Bus master arbitration failure, status %4.4x.\n",
				   dev->name, csr0);
			/* Restart the chip. */
			must_restart = 1;
		}

		if (must_restart) {
			/* stop the chip to clear the error condition, then restart */
			outw(0x0000, dev->base_addr + LANCE_ADDR);
			outw(0x0004, dev->base_addr + LANCE_DATA);
			lance_restart(dev, 0x0002, 0);
		}
	}

	/* Clear any other interrupt, and set interrupt enable. */
	outw(0x0000, dev->base_addr + LANCE_ADDR);
	outw(0x7940, dev->base_addr + LANCE_DATA);

	if (lance_debug > 4)
		printk("%s: exiting interrupt, csr%d=%#4.4x.\n",
			   dev->name, inw(ioaddr + LANCE_ADDR),
			   inw(dev->base_addr + LANCE_DATA));

	dev->interrupt = 0;
	return;
}

static int
lance_rx(struct device *dev)
{
	struct lance_private *lp = (struct lance_private *)dev->priv;
	int entry = lp->cur_rx & RX_RING_MOD_MASK;
	int i;
		
	/* If we own the next entry, it's a new packet. Send it up. */
	while (lp->rx_ring[entry].base >= 0) {
		int status = lp->rx_ring[entry].base >> 24;

		if (status != 0x03) {			/* There was an error. */
			/* There is a tricky error noted by John Murphy,
			   <[e-mail]> to Russ Nelson: Even with full-sized
			   buffers it's possible for a jabber packet to use two
			   buffers, with only the last correctly noting the error. */
			if (status & 0x01)	/* Only count a general error at the */
				lp->stats.rx_errors++; /* end of a packet.*/
			if (status & 0x20) lp->stats.rx_frame_errors++;
			if (status & 0x10) lp->stats.rx_over_errors++;
			if (status & 0x08) lp->stats.rx_crc_errors++;
			if (status & 0x04) lp->stats.rx_fifo_errors++;
			lp->rx_ring[entry].base &= 0x03ffffff;
		}
		else 
		{
			/* Malloc up new buffer, compatible with net3. */
			short pkt_len = (lp->rx_ring[entry].msg_length & 0xfff)-4;
			struct sk_buff *skb;
			
			if(pkt_len<60)
			{
				printk("%s: Runt packet!\n",dev->name);
				lp->stats.rx_errors++;
			}
			else
			{
				skb = dev_alloc_skb(pkt_len+2);
				if (skb == NULL) 
				{
					printk("%s: Memory squeeze, deferring packet.\n", dev->name);
					for (i=0; i < RX_RING_SIZE; i++)
						if (lp->rx_ring[(entry+i) & RX_RING_MOD_MASK].base < 0)
							break;

					if (i > RX_RING_SIZE -2) 
					{
						lp->stats.rx_dropped++;
						lp->rx_ring[entry].base |= 0x80000000;
						lp->cur_rx++;
					}
					break;
				}
				skb->dev = dev;
				skb_reserve(skb,2);	/* 16 byte align */
				skb_put(skb,pkt_len);	/* Make room */
				eth_copy_and_sum(skb,
					(unsigned char *)bus_to_virt((lp->rx_ring[entry].base & 0x00ffffff)),
					pkt_len,0);
				lp->stats.rx_bytes+=skb->len;
				skb->protocol=eth_type_trans(skb,dev);
				lp->stats.rx_packets++;
				netif_rx(skb);
			}
		}
		/* The docs say that the buffer length isn't touched, but Andrew Boyd
		   of QNX reports that some revs of the 79C965 clear it. */
		lp->rx_ring[entry].buf_length = -PKT_BUF_SZ;
		lp->rx_ring[entry].base |= 0x80000000;
		entry = (++lp->cur_rx) & RX_RING_MOD_MASK;
	}

	/* We should check that at least two ring entries are free.	 If not,
	   we should free one and mark stats->rx_dropped++. */

	return 0;
}

static int
lance_close(struct device *dev)
{
	int ioaddr = dev->base_addr;
	struct lance_private *lp = (struct lance_private *)dev->priv;
	int i;

	dev->start = 0;
	dev->tbusy = 1;

	if (chip_table[lp->chip_version].flags & LANCE_HAS_MISSED_FRAME) {
		outw(112, ioaddr+LANCE_ADDR);
		lp->stats.rx_missed_errors = inw(ioaddr+LANCE_DATA);
	}
	outw(0, ioaddr+LANCE_ADDR);

	if (lance_debug > 1)
		printk("%s: Shutting down ethercard, status was %2.2x.\n",
			   dev->name, inw(ioaddr+LANCE_DATA));

	/* We stop the LANCE here -- it occasionally polls
	   memory if we don't. */
	outw(0x0004, ioaddr+LANCE_DATA);

	if (dev->dma != 4)
	{
		unsigned long flags=claim_dma_lock();
		disable_dma(dev->dma);
		release_dma_lock(flags);
	}
	free_irq(dev->irq, dev);

	/* Free all the skbuffs in the Rx and Tx queues. */
	for (i = 0; i < RX_RING_SIZE; i++) {
		struct sk_buff *skb = lp->rx_skbuff[i];
		lp->rx_skbuff[i] = 0;
		lp->rx_ring[i].base = 0;		/* Not owned by LANCE chip. */
		if (skb)
			dev_kfree_skb(skb);
	}
	for (i = 0; i < TX_RING_SIZE; i++) {
		if (lp->tx_skbuff[i])
			dev_kfree_skb(lp->tx_skbuff[i]);
		lp->tx_skbuff[i] = 0;
	}

	MOD_DEC_USE_COUNT;
	return 0;
}

static struct net_device_stats *lance_get_stats(struct device *dev)
{
	struct lance_private *lp = (struct lance_private *)dev->priv;
	short ioaddr = dev->base_addr;
	short saved_addr;
	unsigned long flags;

	if (chip_table[lp->chip_version].flags & LANCE_HAS_MISSED_FRAME) {
		save_flags(flags);
		cli();
		saved_addr = inw(ioaddr+LANCE_ADDR);
		outw(112, ioaddr+LANCE_ADDR);
		lp->stats.rx_missed_errors = inw(ioaddr+LANCE_DATA);
		outw(saved_addr, ioaddr+LANCE_ADDR);
		restore_flags(flags);
	}

	return &lp->stats;
}

/* Set or clear the multicast filter for this adaptor.
 */

static void set_multicast_list(struct device *dev)
{
	short ioaddr = dev->base_addr;

	outw(0, ioaddr+LANCE_ADDR);
	outw(0x0004, ioaddr+LANCE_DATA); /* Temporarily stop the lance.	 */

	if (dev->flags&IFF_PROMISC) {
		/* Log any net taps. */
		printk("%s: Promiscuous mode enabled.\n", dev->name);
		outw(15, ioaddr+LANCE_ADDR);
		outw(0x8000, ioaddr+LANCE_DATA); /* Set promiscuous mode */
	} else {
		short multicast_table[4];
		int i;
		int num_addrs=dev->mc_count;
		if(dev->flags&IFF_ALLMULTI)
			num_addrs=1;
		/* FIXIT: We don't use the multicast table, but rely on upper-layer filtering. */
		memset(multicast_table, (num_addrs == 0) ? 0 : -1, sizeof(multicast_table));
		for (i = 0; i < 4; i++) {
			outw(8 + i, ioaddr+LANCE_ADDR);
			outw(multicast_table[i], ioaddr+LANCE_DATA);
		}
		outw(15, ioaddr+LANCE_ADDR);
		outw(0x0000, ioaddr+LANCE_DATA); /* Unset promiscuous mode */
	}

	lance_restart(dev, 0x0142, 0); /*  Resume normal operation */

}