fec.c

static void mii_relink(struct work_struct *work)
{
	struct fec_enet_private *fep = container_of(work, struct fec_enet_private, phy_task);
	struct net_device *dev = fep->netdev;
	int duplex;

	/*
	** When we get here, phy_task is already removed from
	** the workqueue.  It is thus safe to allow to reuse it.
	*/
	fep->mii_phy_task_queued = 0;
	fep->link = (fep->phy_status & PHY_STAT_LINK) ? 1 : 0;
	mii_display_status(dev);
	fep->old_link = fep->link;

	if (fep->link) {
		duplex = 0;
		if (fep->phy_status
		    & (PHY_STAT_100FDX | PHY_STAT_10FDX))
			duplex = 1;
		fec_restart(dev, duplex);
	}
	else
		fec_stop(dev);

#if 0
	enable_irq(fep->mii_irq);
#endif

}

/* mii_queue_relink is called in interrupt context from mii_link_interrupt */
static void mii_queue_relink(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep = netdev_priv(dev);

	/*
	** We cannot queue phy_task twice in the workqueue.  It
	** would cause an endless loop in the workqueue.
	** Fortunately, if the last mii_relink entry has not yet been
	** executed now, it will do the job for the current interrupt,
	** which is just what we want.
	*/
	if (fep->mii_phy_task_queued)
		return;

	fep->mii_phy_task_queued = 1;
	INIT_WORK(&fep->phy_task, mii_relink);
	schedule_work(&fep->phy_task);
}

/* mii_queue_config is called in interrupt context from fec_enet_mii */
static void mii_queue_config(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep = netdev_priv(dev);

	if (fep->mii_phy_task_queued)
		return;

	fep->mii_phy_task_queued = 1;
	INIT_WORK(&fep->phy_task, mii_display_config);
	schedule_work(&fep->phy_task);
}

phy_cmd_t const phy_cmd_relink[] = {
	{ mk_mii_read(MII_REG_CR), mii_queue_relink },
	{ mk_mii_end, }
	};
phy_cmd_t const phy_cmd_config[] = {
	{ mk_mii_read(MII_REG_CR), mii_queue_config },
	{ mk_mii_end, }
	};

/* Read remainder of PHY ID.
*/
static void
mii_discover_phy3(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep;
	int i;

	fep = netdev_priv(dev);
	fep->phy_id |= (mii_reg & 0xffff);
	printk("fec: PHY @ 0x%x, ID 0x%08x", fep->phy_addr, fep->phy_id);

	for(i = 0; phy_info[i]; i++) {
		if(phy_info[i]->id == (fep->phy_id >> 4))
			break;
	}

	if (phy_info[i])
		printk(" -- %s\n", phy_info[i]->name);
	else
		printk(" -- unknown PHY!\n");

	fep->phy = phy_info[i];
	fep->phy_id_done = 1;
}

/* Scan all of the MII PHY addresses looking for someone to respond
 * with a valid ID.  This usually happens quickly.
 */
static void
mii_discover_phy(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep;
	volatile fec_t *fecp;
	uint phytype;

	fep = netdev_priv(dev);
	fecp = fep->hwp;

	if (fep->phy_addr < 32) {
		if ((phytype = (mii_reg & 0xffff)) != 0xffff && phytype != 0) {

			/* Got first part of ID, now get remainder.
			*/
			fep->phy_id = phytype << 16;
			mii_queue(dev, mk_mii_read(MII_REG_PHYIR2),
							mii_discover_phy3);
		}
		else {
			fep->phy_addr++;
			mii_queue(dev, mk_mii_read(MII_REG_PHYIR1),
							mii_discover_phy);
		}
	} else {
		printk("FEC: No PHY device found.\n");
		/* Disable external MII interface */
		fecp->fec_mii_speed = fep->phy_speed = 0;
		fec_disable_phy_intr();
	}
}

/* This interrupt occurs when the PHY detects a link change.
*/
#ifdef CONFIG_RPXCLASSIC
static void
mii_link_interrupt(void *dev_id)
#else
static irqreturn_t
mii_link_interrupt(int irq, void * dev_id)
#endif
{
	struct	net_device *dev = dev_id;
	struct fec_enet_private *fep = netdev_priv(dev);

	fec_phy_ack_intr();

#if 0
	disable_irq(fep->mii_irq);  /* disable now, enable later */
#endif

	mii_do_cmd(dev, fep->phy->ack_int);
	mii_do_cmd(dev, phy_cmd_relink);  /* restart and display status */

	return IRQ_HANDLED;
}

static int
fec_enet_open(struct net_device *dev)
{
	struct fec_enet_private *fep = netdev_priv(dev);

	/* I should reset the ring buffers here, but I don't yet know
	 * a simple way to do that.
	 */
	fec_set_mac_address(dev);

	fep->sequence_done = 0;
	fep->link = 0;

	if (fep->phy) {
		mii_do_cmd(dev, fep->phy->ack_int);
		mii_do_cmd(dev, fep->phy->config);
		mii_do_cmd(dev, phy_cmd_config);  /* display configuration */

		/* Poll until the PHY tells us its configuration
		 * (not link state).
		 * Request is initiated by mii_do_cmd above, but answer
		 * comes by interrupt.
		 * This should take about 25 usec per register at 2.5 MHz,
		 * and we read approximately 5 registers.
		 */
		while(!fep->sequence_done)
			schedule();

		mii_do_cmd(dev, fep->phy->startup);

		/* Set the initial link state to true. A lot of hardware
		 * based on this device does not implement a PHY interrupt,
		 * so we are never notified of link change.
		 */
		fep->link = 1;
	} else {
		fep->link = 1; /* lets just try it and see */
		/* no phy,  go full duplex,  it's most likely a hub chip */
		fec_restart(dev, 1);
	}

	netif_start_queue(dev);
	fep->opened = 1;
	return 0;		/* Success */
}

static int
fec_enet_close(struct net_device *dev)
{
	struct fec_enet_private *fep = netdev_priv(dev);

	/* Don't know what to do yet.
	*/
	fep->opened = 0;
	netif_stop_queue(dev);
	fec_stop(dev);

	return 0;
}

/* Set or clear the multicast filter for this adaptor.
 * Skeleton taken from sunlance driver.
 * The CPM Ethernet implementation allows Multicast as well as individual
 * MAC address filtering.  Some of the drivers check to make sure it is
 * a group multicast address, and discard those that are not.  I guess I
 * will do the same for now, but just remove the test if you want
 * individual filtering as well (do the upper net layers want or support
 * this kind of feature?).
 */

#define HASH_BITS	6		/* #bits in hash */
#define CRC32_POLY	0xEDB88320

static void set_multicast_list(struct net_device *dev)
{
	struct fec_enet_private *fep;
	volatile fec_t *ep;
	struct dev_mc_list *dmi;
	unsigned int i, j, bit, data, crc;
	unsigned char hash;

	fep = netdev_priv(dev);
	ep = fep->hwp;

	if (dev->flags&IFF_PROMISC) {
		ep->fec_r_cntrl |= 0x0008;
	} else {

		ep->fec_r_cntrl &= ~0x0008;

		if (dev->flags & IFF_ALLMULTI) {
			/* Catch all multicast addresses, so set the
			 * filter to all 1's.
			 */
			ep->fec_hash_table_high = 0xffffffff;
			ep->fec_hash_table_low = 0xffffffff;
		} else {
			/* Clear filter and add the addresses in hash register.
			*/
			ep->fec_hash_table_high = 0;
			ep->fec_hash_table_low = 0;

			dmi = dev->mc_list;

			for (j = 0; j < dev->mc_count; j++, dmi = dmi->next)
			{
				/* Only support group multicast for now.
				*/
				if (!(dmi->dmi_addr[0] & 1))
					continue;

				/* calculate crc32 value of mac address
				*/
				crc = 0xffffffff;

				for (i = 0; i < dmi->dmi_addrlen; i++)
				{
					data = dmi->dmi_addr[i];
					for (bit = 0; bit < 8; bit++, data >>= 1)
					{
						crc = (crc >> 1) ^
						(((crc ^ data) & 1) ? CRC32_POLY : 0);
					}
				}

				/* only upper 6 bits (HASH_BITS) are used
				   which point to specific bit in he hash registers
				*/
				hash = (crc >> (32 - HASH_BITS)) & 0x3f;

				if (hash > 31)
					ep->fec_hash_table_high |= 1 << (hash - 32);
				else
					ep->fec_hash_table_low |= 1 << hash;
			}
		}
	}
}

/* Set a MAC change in hardware.
 */
static void
fec_set_mac_address(struct net_device *dev)
{
	volatile fec_t *fecp;

	fecp = ((struct fec_enet_private *)netdev_priv(dev))->hwp;

	/* Set station address. */
	fecp->fec_addr_low = dev->dev_addr[3] | (dev->dev_addr[2] << 8) |
		(dev->dev_addr[1] << 16) | (dev->dev_addr[0] << 24);
	fecp->fec_addr_high = (dev->dev_addr[5] << 16) |
		(dev->dev_addr[4] << 24);

}

/* Initialize the FEC Ethernet on 860T (or ColdFire 5272).
 */
 /*
  * XXX:  We need to clean up on failure exits here.
  */
int __init fec_enet_init(struct net_device *dev)
{
	struct fec_enet_private *fep = netdev_priv(dev);
	unsigned long	mem_addr;
	volatile cbd_t	*bdp;
	cbd_t		*cbd_base;
	volatile fec_t	*fecp;
	int 		i, j;
	static int	index = 0;

	/* Only allow us to be probed once. */
	if (index >= FEC_MAX_PORTS)
		return -ENXIO;

	/* Allocate memory for buffer descriptors.
	*/
	mem_addr = __get_free_page(GFP_KERNEL);
	if (mem_addr == 0) {
		printk("FEC: allocate descriptor memory failed?\n");
		return -ENOMEM;
	}

	/* Create an Ethernet device instance.
	*/
	fecp = (volatile fec_t *) fec_hw[index];

	fep->index = index;
	fep->hwp = fecp;
	fep->netdev = dev;

	/* Whack a reset.  We should wait for this.
	*/
	fecp->fec_ecntrl = 1;
	udelay(10);

	/* Set the Ethernet address.  If using multiple Enets on the 8xx,
	 * this needs some work to get unique addresses.
	 *
	 * This is our default MAC address unless the user changes
	 * it via eth_mac_addr (our dev->set_mac_addr handler).
	 */
	fec_get_mac(dev);

	cbd_base = (cbd_t *)mem_addr;
	/* XXX: missing check for allocation failure */

	fec_uncache(mem_addr);

	/* Set receive and transmit descriptor base.
	*/
	fep->rx_bd_base = cbd_base;
	fep->tx_bd_base = cbd_base + RX_RING_SIZE;

	fep->dirty_tx = fep->cur_tx = fep->tx_bd_base;
	fep->cur_rx = fep->rx_bd_base;

	fep->skb_cur = fep->skb_dirty = 0;

	/* Initialize the receive buffer descriptors.
	*/
	bdp = fep->rx_bd_base;
	for (i=0; i<FEC_ENET_RX_PAGES; i++) {

		/* Allocate a page.
		*/
		mem_addr = __get_free_page(GFP_KERNEL);
		/* XXX: missing check for allocation failure */

		fec_uncache(mem_addr);

		/* Initialize the BD for every fragment in the page.
		*/
		for (j=0; j<FEC_ENET_RX_FRPPG; j++) {
			bdp->cbd_sc = BD_ENET_RX_EMPTY;
			bdp->cbd_bufaddr = __pa(mem_addr);
			mem_addr += FEC_ENET_RX_FRSIZE;
			bdp++;
		}
	}

	/* Set the last buffer to wrap.
	*/
	bdp--;
	bdp->cbd_sc |= BD_SC_WRAP;

	/* ...and the same for transmmit.
	*/
	bdp = fep->tx_bd_base;
	for (i=0, j=FEC_ENET_TX_FRPPG; i<TX_RING_SIZE; i++) {
		if (j >= FEC_ENET_TX_FRPPG) {
			mem_addr = __get_free_page(GFP_KERNEL);
			j = 1;
		} else {
			mem_addr += FEC_ENET_TX_FRSIZE;
			j++;
		}
		fep->tx_bounce[i] = (unsigned char *) mem_addr;

		/* Initialize the BD for every fragment in the page.
		*/
		bdp->cbd_sc = 0;
		bdp->cbd_bufaddr = 0;
		bdp++;
	}

	/* Set the last buffer to wrap.
	*/
	bdp--;
	bdp->cbd_sc |= BD_SC_WRAP;

	/* Set receive and transmit descriptor base.
	*/
	fecp->fec_r_des_start = __pa((uint)(fep->rx_bd_base));
	fecp->fec_x_des_start = __pa((uint)(fep->tx_bd_base));

	/* Install our interrupt handlers. This varies depending on
	 * the architecture.
	*/
	fec_request_intrs(dev);

	fecp->fec_hash_table_high = 0;
	fecp->fec_hash_table_low = 0;
	fecp->fec_r_buff_size = PKT_MAXBLR_SIZE;
	fecp->fec_ecntrl = 2;
	fecp->fec_r_des_active = 0;

	dev->base_addr = (unsigned long)fecp;

	/* The FEC Ethernet specific entries in the device structure. */
	dev->open = fec_enet_open;
	dev->hard_start_xmit = fec_enet_start_xmit;
	dev->tx_timeout = fec_timeout;
	dev->watchdog_timeo = TX_TIMEOUT;
	dev->stop = fec_enet_close;
	dev->set_multicast_list = set_multicast_list;

	for (i=0; i<NMII-1; i++)
		mii_cmds[i].mii_next = &mii_cmds[i+1];
	mii_free = mii_cmds;

	/* setup MII interface */
	fec_set_mii(dev, fep);

	/* Clear and enable interrupts */
	fecp->fec_ievent = 0xffc00000;
	fecp->fec_imask = (FEC_ENET_TXF | FEC_ENET_TXB |
		FEC_ENET_RXF | FEC_ENET_RXB | FEC_ENET_MII);

	/* Queue up command to detect the PHY and initialize the
	 * remainder of the interface.
	 */
	fep->phy_id_done = 0;
	fep->phy_addr = 0;
	mii_queue(dev, mk_mii_read(MII_REG_PHYIR1), mii_discover_phy);

	index++;
	return 0;
}

/* This function is called to start or restart the FEC during a link
 * change.  This only happens when switching between half and full
 * duplex.
 */
static void
fec_restart(struct net_device *dev, int duplex)
{
	struct fec_enet_private *fep;
	volatile cbd_t *bdp;
	volatile fec_t *fecp;
	int i;

	fep = netdev_priv(dev);
	fecp = fep->hwp;

	/* Whack a reset.  We should wait for this.
	*/
	fecp->fec_ecntrl = 1;
	udelay(10);

	/* Clear any outstanding interrupt.
	*/
	fecp->fec_ievent = 0xffc00000;
	fec_enable_phy_intr();

	/* Set station address.
	*/
	fec_set_mac_address(dev);

	/* Reset all multicast.
	*/
	fecp->fec_hash_table_high = 0;
	fecp->fec_hash_table_low = 0;

	/* Set maximum receive buffer size.
	*/
	fecp->fec_r_buff_size = PKT_MAXBLR_SIZE;

	fec_localhw_setup();

	/* Set receive and transmit descriptor base.
	*/
	fecp->fec_r_des_start = __pa((uint)(fep->rx_bd_base));
	fecp->fec_x_des_start = __pa((uint)(fep->tx_bd_base));

	fep->dirty_tx = fep->cur_tx = fep->tx_bd_base;
	fep->cur_rx = fep->rx_bd_base;

	/* Reset SKB transmit buffers.
	*/
	fep->skb_cur = fep->skb_dirty = 0;
	for (i=0; i<=TX_RING_MOD_MASK; i++) {
		if (fep->tx_skbuff[i] != NULL) {
			dev_kfree_skb_any(fep->tx_skbuff[i]);
			fep->tx_skbuff[i] = NULL;
		}
	}

	/* Initialize the receive buffer descriptors.
	*/
	bdp = fep->rx_bd_base;
	for (i=0; i<RX_RING_SIZE; i++) {

		/* Initialize the BD for every fragment in the page.
		*/
		bdp->cbd_sc = BD_ENET_RX_EMPTY;
		bdp++;
	}

	/* Set the last buffer to wrap.
	*/
	bdp--;
	bdp->cbd_sc |= BD_SC_WRAP;

	/* ...and the same for transmmit.
	*/
	bdp = fep->tx_bd_base;
	for (i=0; i<TX_RING_SIZE; i++) {

		/* Initialize the BD for every fragment in the page.
		*/
		bdp->cbd_sc = 0;
		bdp->cbd_bufaddr = 0;
		bdp++;
	}

	/* Set the last buffer to wrap.
	*/
	bdp--;
	bdp->cbd_sc |= BD_SC_WRAP;

	/* Enable MII mode.
	*/
	if (duplex) {
		fecp->fec_r_cntrl = OPT_FRAME_SIZE | 0x04;/* MII enable */
		fecp->fec_x_cntrl = 0x04;		  /* FD enable */
	}
	else {
		/* MII enable|No Rcv on Xmit */
		fecp->fec_r_cntrl = OPT_FRAME_SIZE | 0x06;
		fecp->fec_x_cntrl = 0x00;
	}
	fep->full_duplex = duplex;

	/* Set MII speed.
	*/
	fecp->fec_mii_speed = fep->phy_speed;

	/* And last, enable the transmit and receive processing.
	*/
	fecp->fec_ecntrl = 2;
	fecp->fec_r_des_active = 0;

	/* Enable interrupts we wish to service.
	*/
	fecp->fec_imask = (FEC_ENET_TXF | FEC_ENET_TXB |
		FEC_ENET_RXF | FEC_ENET_RXB | FEC_ENET_MII);
}

static void
fec_stop(struct net_device *dev)
{
	volatile fec_t *fecp;
	struct fec_enet_private *fep;

	fep = netdev_priv(dev);
	fecp = fep->hwp;

	/*
	** We cannot expect a graceful transmit stop without link !!!
	*/
	if (fep->link)
		{
		fecp->fec_x_cntrl = 0x01;	/* Graceful transmit stop */
		udelay(10);
		if (!(fecp->fec_ievent & FEC_ENET_GRA))
			printk("fec_stop : Graceful transmit stop did not complete !\n");
		}

	/* Whack a reset.  We should wait for this.
	*/
	fecp->fec_ecntrl = 1;
	udelay(10);

	/* Clear outstanding MII command interrupts.
	*/
	fecp->fec_ievent = FEC_ENET_MII;
	fec_enable_phy_intr();

	fecp->fec_imask = FEC_ENET_MII;
	fecp->fec_mii_speed = fep->phy_speed;
}

static int __init fec_enet_module_init(void)
{
	struct net_device *dev;
	int i, j, err;
	DECLARE_MAC_BUF(mac);

	printk("FEC ENET Version 0.2\n");

	for (i = 0; (i < FEC_MAX_PORTS); i++) {
		dev = alloc_etherdev(sizeof(struct fec_enet_private));
		if (!dev)
			return -ENOMEM;
		err = fec_enet_init(dev);
		if (err) {
			free_netdev(dev);
			continue;
		}
		if (register_netdev(dev) != 0) {
			/* XXX: missing cleanup here */
			free_netdev(dev);
			return -EIO;
		}

		printk("%s: ethernet %s\n",
		       dev->name, print_mac(mac, dev->dev_addr));
	}
	return 0;
}

module_init(fec_enet_module_init);

MODULE_LICENSE("GPL");