8139too.c

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#endif /* RTL8139_NDEBUG */

	/* only wake the queue if we did work, and the queue is stopped */
	if (tp->dirty_tx != dirty_tx) {
		tp->dirty_tx = dirty_tx;
		mb();
		if (netif_queue_stopped (dev))
			netif_wake_queue (dev);
	}
}


/* TODO: clean this up!  Rx reset need not be this intensive */
static void rtl8139_rx_err (u32 rx_status, struct net_device *dev,
			    struct rtl8139_private *tp, void *ioaddr)
{
	u8 tmp8;
	int tmp_work = 1000;

	DPRINTK ("%s: Ethernet frame had errors, status %8.8x.\n",
	         dev->name, rx_status);
	if (rx_status & RxTooLong) {
		DPRINTK ("%s: Oversized Ethernet frame, status %4.4x!\n",
			 dev->name, rx_status);
		/* A.C.: The chip hangs here. */
	}
	tp->stats.rx_errors++;
	if (rx_status & (RxBadSymbol | RxBadAlign))
		tp->stats.rx_frame_errors++;
	if (rx_status & (RxRunt | RxTooLong))
		tp->stats.rx_length_errors++;
	if (rx_status & RxCRCErr)
		tp->stats.rx_crc_errors++;
	/* Reset the receiver, based on RealTek recommendation. (Bug?) */
	tp->cur_rx = 0;

	/* disable receive */
	tmp8 = RTL_R8 (ChipCmd) & ChipCmdClear;
	RTL_W8_F (ChipCmd, tmp8 | CmdTxEnb);

	/* A.C.: Reset the multicast list. */
	rtl8139_set_rx_mode (dev);

	/* XXX potentially temporary hack to
	 * restart hung receiver */
	while (--tmp_work > 0) {
		tmp8 = RTL_R8 (ChipCmd);
		if ((tmp8 & CmdRxEnb) && (tmp8 & CmdTxEnb))
			break;
		RTL_W8_F (ChipCmd,
			  (tmp8 & ChipCmdClear) | CmdRxEnb | CmdTxEnb);
	}

	/* G.S.: Re-enable receiver */
	/* XXX temporary hack to work around receiver hang */
	rtl8139_set_rx_mode (dev);

	if (tmp_work <= 0)
		printk (KERN_WARNING PFX "tx/rx enable wait too long\n");
}


/* The data sheet doesn't describe the Rx ring at all, so I'm guessing at the
   field alignments and semantics. */
static void rtl8139_rx_interrupt (struct net_device *dev,
				  struct rtl8139_private *tp, void *ioaddr)
{
	unsigned char *rx_ring;
	u16 cur_rx;

	assert (dev != NULL);
	assert (tp != NULL);
	assert (ioaddr != NULL);

	rx_ring = tp->rx_ring;
	cur_rx = tp->cur_rx;

	DPRINTK ("%s: In rtl8139_rx(), current %4.4x BufAddr %4.4x,"
		 " free to %4.4x, Cmd %2.2x.\n", dev->name, cur_rx,
		 RTL_R16 (RxBufAddr),
		 RTL_R16 (RxBufPtr), RTL_R8 (ChipCmd));

	while ((RTL_R8 (ChipCmd) & RxBufEmpty) == 0) {
		int ring_offset = cur_rx % RX_BUF_LEN;
		u32 rx_status;
		unsigned int rx_size;
		unsigned int pkt_size;
		struct sk_buff *skb;

		/* read size+status of next frame from DMA ring buffer */
		rx_status = le32_to_cpu (*(u32 *) (rx_ring + ring_offset));
		rx_size = rx_status >> 16;
		pkt_size = rx_size - 4;

		DPRINTK ("%s:  rtl8139_rx() status %4.4x, size %4.4x,"
			 " cur %4.4x.\n", dev->name, rx_status,
			 rx_size, cur_rx);
#if RTL8139_DEBUG > 2
		{
			int i;
			DPRINTK ("%s: Frame contents ", dev->name);
			for (i = 0; i < 70; i++)
				printk (" %2.2x",
					rx_ring[ring_offset + i]);
			printk (".\n");
		}
#endif

		/* E. Gill */
		/* Note from BSD driver:
		 * Here's a totally undocumented fact for you. When the
		 * RealTek chip is in the process of copying a packet into
		 * RAM for you, the length will be 0xfff0. If you spot a
		 * packet header with this value, you need to stop. The
		 * datasheet makes absolutely no mention of this and
		 * RealTek should be shot for this.
		 */
		if (rx_size == 0xfff0)
			break;

		/* If Rx err or invalid rx_size/rx_status received
		 * (which happens if we get lost in the ring),
		 * Rx process gets reset, so we abort any further
		 * Rx processing.
		 */
		if ((rx_size > (MAX_ETH_FRAME_SIZE+4)) ||
		    (!(rx_status & RxStatusOK))) {
			rtl8139_rx_err (rx_status, dev, tp, ioaddr);
			return;
		}

		/* Malloc up new buffer, compatible with net-2e. */
		/* Omit the four octet CRC from the length. */

		/* TODO: consider allocating skb's outside of
		 * interrupt context, both to speed interrupt processing,
		 * and also to reduce the chances of having to
		 * drop packets here under memory pressure.
		 */

		skb = dev_alloc_skb (pkt_size + 2);
		if (skb) {
			skb->dev = dev;
			skb_reserve (skb, 2);	/* 16 byte align the IP fields. */

			eth_copy_and_sum (skb, &rx_ring[ring_offset + 4], pkt_size, 0);
			skb_put (skb, pkt_size);

			skb->protocol = eth_type_trans (skb, dev);
			netif_rx (skb);
			tp->stats.rx_bytes += pkt_size;
			tp->stats.rx_packets++;
		} else {
			printk (KERN_WARNING
				"%s: Memory squeeze, dropping packet.\n",
				dev->name);
			tp->stats.rx_dropped++;
		}

		cur_rx = (cur_rx + rx_size + 4 + 3) & ~3;
		RTL_W16_F (RxBufPtr, cur_rx - 16);
	}

	DPRINTK ("%s: Done rtl8139_rx(), current %4.4x BufAddr %4.4x,"
		 " free to %4.4x, Cmd %2.2x.\n", dev->name, cur_rx,
		 RTL_R16 (RxBufAddr),
		 RTL_R16 (RxBufPtr), RTL_R8 (ChipCmd));

	tp->cur_rx = cur_rx;
}


static void rtl8139_weird_interrupt (struct net_device *dev,
				     struct rtl8139_private *tp,
				     void *ioaddr,
				     int status, int link_changed)
{
	printk (KERN_DEBUG "%s: Abnormal interrupt, status %8.8x.\n",
		dev->name, status);

	assert (dev != NULL);
	assert (tp != NULL);
	assert (ioaddr != NULL);

	/* Update the error count. */
	tp->stats.rx_missed_errors += RTL_R32 (RxMissed);
	RTL_W32 (RxMissed, 0);

	if ((status & RxUnderrun) && link_changed &&
	    (tp->drv_flags & HAS_LNK_CHNG)) {
		/* Really link-change on new chips. */
		int lpar = RTL_R16 (NWayLPAR);
		int duplex = (lpar & 0x0100) || (lpar & 0x01C0) == 0x0040
				|| tp->duplex_lock;
		if (tp->full_duplex != duplex) {
			tp->full_duplex = duplex;
			RTL_W8 (Cfg9346, Cfg9346_Unlock);
			RTL_W8 (Config1, tp->full_duplex ? 0x60 : 0x20);
			RTL_W8 (Cfg9346, Cfg9346_Lock);
		}
		status &= ~RxUnderrun;
	}

	/* XXX along with rtl8139_rx_err, are we double-counting errors? */
	if (status &
	    (RxUnderrun | RxOverflow | RxErr | RxFIFOOver))
		tp->stats.rx_errors++;

	if (status & (PCSTimeout))
		tp->stats.rx_length_errors++;
	if (status & (RxUnderrun | RxFIFOOver))
		tp->stats.rx_fifo_errors++;
	if (status & RxOverflow) {
		tp->stats.rx_over_errors++;
		tp->cur_rx = RTL_R16 (RxBufAddr) % RX_BUF_LEN;
		RTL_W16_F (RxBufPtr, tp->cur_rx - 16);
	}
	if (status & PCIErr) {
		u16 pci_cmd_status;
		pci_read_config_word (tp->pci_dev, PCI_STATUS, &pci_cmd_status);

		printk (KERN_ERR "%s: PCI Bus error %4.4x.\n",
			dev->name, pci_cmd_status);
	}
}


/* The interrupt handler does all of the Rx thread work and cleans up
   after the Tx thread. */
static void rtl8139_interrupt (int irq, void *dev_instance,
			       struct pt_regs *regs)
{
	struct net_device *dev = (struct net_device *) dev_instance;
	struct rtl8139_private *tp = dev->priv;
	int boguscnt = max_interrupt_work;
	void *ioaddr = tp->mmio_addr;
	int status = 0, link_changed = 0; /* avoid bogus "uninit" warning */

	spin_lock (&tp->lock);

	do {
		status = RTL_R16 (IntrStatus);

		/* h/w no longer present (hotplug?) or major error, bail */
		if (status == 0xFFFF)
			break;

		/* Acknowledge all of the current interrupt sources ASAP, but
		   an first get an additional status bit from CSCR. */
		if (status & RxUnderrun)
			link_changed = RTL_R16 (CSCR) & CSCR_LinkChangeBit;

		/* E. Gill */
		/* In case of an RxFIFOOver we must also clear the RxOverflow
		   bit to avoid dropping frames for ever. Believe me, I got a
		   lot of troubles copying huge data (approximately 2 RxFIFOOver
		   errors per 1GB data transfer).
		   The following is written in the 'p-guide.pdf' file (RTL8139(A/B)
		   Programming guide V0.1, from 1999/1/15) on page 9 from REALTEC.
		   -----------------------------------------------------------
		   2. RxFIFOOvw handling:
		     When RxFIFOOvw occurs, all incoming packets are discarded.
		     Clear ISR(RxFIFOOvw) doesn't dismiss RxFIFOOvw event. To
		     dismiss RxFIFOOvw event, the ISR(RxBufOvw) must be written
		     with a '1'.
		   -----------------------------------------------------------
		   Unfortunately I was not able to find any reason for the
		   RxFIFOOver error (I got the feeling this depends on the
		   CPU speed, lower CPU speed --> more errors).
		   After clearing the RxOverflow bit the transfer of the
		   packet was repeated and all data are error free transfered */
		RTL_W16_F (IntrStatus, (status & RxFIFOOver) ? (status | RxOverflow) : status);

		DPRINTK ("%s: interrupt  status=%#4.4x new intstat=%#4.4x.\n",
				dev->name, status,
				RTL_R16 (IntrStatus));

		if ((status &
		     (PCIErr | PCSTimeout | RxUnderrun | RxOverflow |
		      RxFIFOOver | TxErr | TxOK | RxErr | RxOK)) == 0)
			break;

		/* Check uncommon events with one test. */
		if (status & (PCIErr | PCSTimeout | RxUnderrun | RxOverflow |
		  	      RxFIFOOver | TxErr | RxErr))
			rtl8139_weird_interrupt (dev, tp, ioaddr,
						 status, link_changed);

		if (status & (RxOK | RxUnderrun | RxOverflow | RxFIFOOver))	/* Rx interrupt */
			rtl8139_rx_interrupt (dev, tp, ioaddr);

		if (status & (TxOK | TxErr))
			rtl8139_tx_interrupt (dev, tp, ioaddr);

		boguscnt--;
	} while (boguscnt > 0);

	if (boguscnt <= 0) {
		printk (KERN_WARNING
			"%s: Too much work at interrupt, "
			"IntrStatus=0x%4.4x.\n", dev->name,
			status);

		/* Clear all interrupt sources. */
		RTL_W16 (IntrStatus, 0xffff);
	}

	spin_unlock (&tp->lock);

	DPRINTK ("%s: exiting interrupt, intr_status=%#4.4x.\n",
		 dev->name, RTL_R16 (IntrStatus));
}


static int rtl8139_close (struct net_device *dev)
{
	struct rtl8139_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;
	int ret = 0;

	DPRINTK ("ENTER\n");

	netif_stop_queue (dev);

	if (tp->thr_pid >= 0) {
		ret = kill_proc (tp->thr_pid, SIGTERM, 1);
		if (ret) {
			printk (KERN_ERR "%s: unable to signal thread\n", dev->name);
			return ret;
		}
		down (&tp->thr_exited);
	}

	DPRINTK ("%s: Shutting down ethercard, status was 0x%4.4x.\n",
			dev->name, RTL_R16 (IntrStatus));

	spin_lock_irq (&tp->lock);

	/* Stop the chip's Tx and Rx DMA processes. */
	RTL_W8 (ChipCmd, (RTL_R8 (ChipCmd) & ChipCmdClear));

	/* Disable interrupts by clearing the interrupt mask. */
	RTL_W16 (IntrMask, 0x0000);

	/* Update the error counts. */
	tp->stats.rx_missed_errors += RTL_R32 (RxMissed);
	RTL_W32 (RxMissed, 0);

	spin_unlock_irq (&tp->lock);

	synchronize_irq ();
	free_irq (dev->irq, dev);

	rtl8139_tx_clear (tp);

	pci_free_consistent(tp->pci_dev, RX_BUF_TOT_LEN,
			    tp->rx_ring, tp->rx_ring_dma);
	pci_free_consistent(tp->pci_dev, TX_BUF_TOT_LEN,
			    tp->tx_bufs, tp->tx_bufs_dma);
	tp->rx_ring = NULL;
	tp->tx_bufs = NULL;

	/* Green! Put the chip in low-power mode. */
	RTL_W8 (Cfg9346, Cfg9346_Unlock);
	RTL_W8 (Config1, 0x03);
	RTL_W8 (HltClk, 'H');	/* 'R' would leave the clock running. */

	DPRINTK ("EXIT\n");
	return 0;
}


static int mii_ioctl (struct net_device *dev, struct ifreq *rq, int cmd)
{
	struct rtl8139_private *tp = dev->priv;
	u16 *data = (u16 *) & rq->ifr_data;
	int rc = 0;

	DPRINTK ("ENTER\n");

	switch (cmd) {
	case SIOCDEVPRIVATE:	/* Get the address of the PHY in use. */
		data[0] = tp->phys[0] & 0x3f;
		/* Fall Through */

	case SIOCDEVPRIVATE + 1:	/* Read the specified MII register. */
		data[3] = mdio_read (dev, data[0], data[1] & 0x1f);
		break;

	case SIOCDEVPRIVATE + 2:	/* Write the specified MII register */
		if (!capable (CAP_NET_ADMIN)) {
			rc = -EPERM;
			break;
		}

		mdio_write (dev, data[0], data[1] & 0x1f, data[2]);
		break;

	default:
		rc = -EOPNOTSUPP;
		break;
	}

	DPRINTK ("EXIT, returning %d\n", rc);
	return rc;
}


static struct net_device_stats *rtl8139_get_stats (struct net_device *dev)
{
	struct rtl8139_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;

	DPRINTK ("ENTER\n");

	if (netif_running(dev)) {
		tp->stats.rx_missed_errors += RTL_R32 (RxMissed);
		RTL_W32 (RxMissed, 0);
	}

	DPRINTK ("EXIT\n");
	return &tp->stats;
}

/* Set or clear the multicast filter for this adaptor.
   This routine is not state sensitive and need not be SMP locked. */

static unsigned const ethernet_polynomial = 0x04c11db7U;
static inline u32 ether_crc (int length, unsigned char *data)
{
	int crc = -1;

	DPRINTK ("ENTER\n");

	while (--length >= 0) {
		unsigned char current_octet = *data++;
		int bit;
		for (bit = 0; bit < 8; bit++, current_octet >>= 1)
			crc = (crc << 1) ^
			    ((crc < 0) ^ (current_octet & 1) ?
			     ethernet_polynomial : 0);
	}

	DPRINTK ("EXIT\n");
	return crc;
}


static void rtl8139_set_rx_mode (struct net_device *dev)
{
	struct rtl8139_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;
	u32 mc_filter[2];	/* Multicast hash filter */
	int i, rx_mode;
	u32 tmp;

	DPRINTK ("ENTER\n");

	DPRINTK ("%s:   rtl8139_set_rx_mode(%4.4x) done -- Rx config %8.8lx.\n",
			dev->name, dev->flags, RTL_R32 (RxConfig));

	/* Note: do not reorder, GCC is clever about common statements. */
	if (dev->flags & IFF_PROMISC) {
		/* Unconditionally log net taps. */
		printk (KERN_NOTICE "%s: Promiscuous mode enabled.\n",
			dev->name);
		rx_mode =
		    AcceptBroadcast | AcceptMulticast | AcceptMyPhys |
		    AcceptAllPhys;
		mc_filter[1] = mc_filter[0] = 0xffffffff;
	} else if ((dev->mc_count > multicast_filter_limit)
		   || (dev->flags & IFF_ALLMULTI)) {
		/* Too many to filter perfectly -- accept all multicasts. */
		rx_mode = AcceptBroadcast | AcceptMulticast | AcceptMyPhys;
		mc_filter[1] = mc_filter[0] = 0xffffffff;
	} else {
		struct dev_mc_list *mclist;
		rx_mode = AcceptBroadcast | AcceptMulticast | AcceptMyPhys;
		mc_filter[1] = mc_filter[0] = 0;
		for (i = 0, mclist = dev->mc_list; mclist && i < dev->mc_count;
		     i++, mclist = mclist->next)
			set_bit (ether_crc (ETH_ALEN, mclist->dmi_addr) >> 26,
				 mc_filter);
	}

	/* if called from irq handler, lock already acquired */
	if (!in_irq ())
		spin_lock_irq (&tp->lock);

	/* We can safely update without stopping the chip. */
	tmp = rtl8139_rx_config | rx_mode |
		(RTL_R32 (RxConfig) & rtl_chip_info[tp->chipset].RxConfigMask);
	RTL_W32_F (RxConfig, tmp);
	RTL_W32_F (MAR0 + 0, mc_filter[0]);
	RTL_W32_F (MAR0 + 4, mc_filter[1]);

	if (!in_irq ())
		spin_unlock_irq (&tp->lock);

	DPRINTK ("EXIT\n");
}


static void rtl8139_suspend (struct pci_dev *pdev)
{
	struct net_device *dev = pdev->driver_data;
	struct rtl8139_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;
	unsigned long flags;

	netif_device_detach (dev);

	spin_lock_irqsave (&tp->lock, flags);

	/* Disable interrupts, stop Tx and Rx. */
	RTL_W16 (IntrMask, 0x0000);
	RTL_W8 (ChipCmd, (RTL_R8 (ChipCmd) & ChipCmdClear));

	/* Update the error counts. */
	tp->stats.rx_missed_errors += RTL_R32 (RxMissed);
	RTL_W32 (RxMissed, 0);

	spin_unlock_irqrestore (&tp->lock, flags);
}


static void rtl8139_resume (struct pci_dev *pdev)
{
	struct net_device *dev = pdev->driver_data;

	netif_device_attach (dev);
	rtl8139_hw_start (dev);
}


static struct pci_driver rtl8139_pci_driver = {
	name:		MODNAME,
	id_table:	rtl8139_pci_tbl,
	probe:		rtl8139_init_one,
	remove:		rtl8139_remove_one,
	suspend:	rtl8139_suspend,
	resume:		rtl8139_resume,
};


static int __init rtl8139_init_module (void)
{
	return pci_module_init (&rtl8139_pci_driver);
}


static void __exit rtl8139_cleanup_module (void)
{
	pci_unregister_driver (&rtl8139_pci_driver);
}


module_init(rtl8139_init_module);
module_exit(rtl8139_cleanup_module);