bfin_mac.c

来自「linux 内核源代码」· C语言 代码 · 共 1,080 行 · 第 1/2 页

	if (tx_list_head->status.status_word != 0
	    && current_tx_ptr != tx_list_head) {
		goto adjust_head;	/* released something, just return; */
	}

	/*
	 * if nothing released, check wait condition
	 * current's next can not be the head,
	 * otherwise the dma will not stop as we want
	 */
	if (current_tx_ptr->next->next == tx_list_head) {
		while (tx_list_head->status.status_word == 0) {
			mdelay(10);
			if (tx_list_head->status.status_word != 0
			    || !(bfin_read_DMA2_IRQ_STATUS() & 0x08)) {
				goto adjust_head;
			}
			if (timeout_cnt-- < 0) {
				printk(KERN_ERR DRV_NAME
				": wait for adjust tx list head timeout\n");
				break;
			}
		}
		if (tx_list_head->status.status_word != 0) {
			goto adjust_head;
		}
	}

	return;

adjust_head:
	do {
		tx_list_head->desc_a.config &= ~DMAEN;
		tx_list_head->status.status_word = 0;
		if (tx_list_head->skb) {
			dev_kfree_skb(tx_list_head->skb);
			tx_list_head->skb = NULL;
		} else {
			printk(KERN_ERR DRV_NAME
			       ": no sk_buff in a transmitted frame!\n");
		}
		tx_list_head = tx_list_head->next;
	} while (tx_list_head->status.status_word != 0
		 && current_tx_ptr != tx_list_head);
	return;

}

static int bf537mac_hard_start_xmit(struct sk_buff *skb,
				struct net_device *dev)
{
	struct bf537mac_local *lp = netdev_priv(dev);
	unsigned int data;

	current_tx_ptr->skb = skb;

	/*
	 * Is skb->data always 16-bit aligned?
	 * Do we need to memcpy((char *)(tail->packet + 2), skb->data, len)?
	 */
	if ((((unsigned int)(skb->data)) & 0x02) == 2) {
		/* move skb->data to current_tx_ptr payload */
		data = (unsigned int)(skb->data) - 2;
		*((unsigned short *)data) = (unsigned short)(skb->len);
		current_tx_ptr->desc_a.start_addr = (unsigned long)data;
		/* this is important! */
		blackfin_dcache_flush_range(data, (data + (skb->len)) + 2);

	} else {
		*((unsigned short *)(current_tx_ptr->packet)) =
		    (unsigned short)(skb->len);
		memcpy((char *)(current_tx_ptr->packet + 2), skb->data,
		       (skb->len));
		current_tx_ptr->desc_a.start_addr =
		    (unsigned long)current_tx_ptr->packet;
		if (current_tx_ptr->status.status_word != 0)
			current_tx_ptr->status.status_word = 0;
		blackfin_dcache_flush_range((unsigned int)current_tx_ptr->
					    packet,
					    (unsigned int)(current_tx_ptr->
							   packet + skb->len) +
					    2);
	}

	/* enable this packet's dma */
	current_tx_ptr->desc_a.config |= DMAEN;

	/* tx dma is running, just return */
	if (bfin_read_DMA2_IRQ_STATUS() & 0x08)
		goto out;

	/* tx dma is not running */
	bfin_write_DMA2_NEXT_DESC_PTR(&(current_tx_ptr->desc_a));
	/* dma enabled, read from memory, size is 6 */
	bfin_write_DMA2_CONFIG(current_tx_ptr->desc_a.config);
	/* Turn on the EMAC tx */
	bfin_write_EMAC_OPMODE(bfin_read_EMAC_OPMODE() | TE);

out:
	adjust_tx_list();
	current_tx_ptr = current_tx_ptr->next;
	dev->trans_start = jiffies;
	dev->stats.tx_packets++;
	dev->stats.tx_bytes += (skb->len);
	return 0;
}

static void bf537mac_rx(struct net_device *dev)
{
	struct sk_buff *skb, *new_skb;
	struct bf537mac_local *lp = netdev_priv(dev);
	unsigned short len;

	/* allocate a new skb for next time receive */
	skb = current_rx_ptr->skb;
	new_skb = dev_alloc_skb(PKT_BUF_SZ + 2);
	if (!new_skb) {
		printk(KERN_NOTICE DRV_NAME
		       ": rx: low on mem - packet dropped\n");
		dev->stats.rx_dropped++;
		goto out;
	}
	/* reserve 2 bytes for RXDWA padding */
	skb_reserve(new_skb, 2);
	current_rx_ptr->skb = new_skb;
	current_rx_ptr->desc_a.start_addr = (unsigned long)new_skb->data - 2;

	len = (unsigned short)((current_rx_ptr->status.status_word) & RX_FRLEN);
	skb_put(skb, len);
	blackfin_dcache_invalidate_range((unsigned long)skb->head,
					 (unsigned long)skb->tail);

	dev->last_rx = jiffies;
	skb->dev = dev;
	skb->protocol = eth_type_trans(skb, dev);
#if defined(BFIN_MAC_CSUM_OFFLOAD)
	skb->csum = current_rx_ptr->status.ip_payload_csum;
	skb->ip_summed = CHECKSUM_COMPLETE;
#endif

	netif_rx(skb);
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += len;
	current_rx_ptr->status.status_word = 0x00000000;
	current_rx_ptr = current_rx_ptr->next;

out:
	return;
}

/* interrupt routine to handle rx and error signal */
static irqreturn_t bf537mac_interrupt(int irq, void *dev_id)
{
	struct net_device *dev = dev_id;
	int number = 0;

get_one_packet:
	if (current_rx_ptr->status.status_word == 0) {
		/* no more new packet received */
		if (number == 0) {
			if (current_rx_ptr->next->status.status_word != 0) {
				current_rx_ptr = current_rx_ptr->next;
				goto real_rx;
			}
		}
		bfin_write_DMA1_IRQ_STATUS(bfin_read_DMA1_IRQ_STATUS() |
					   DMA_DONE | DMA_ERR);
		return IRQ_HANDLED;
	}

real_rx:
	bf537mac_rx(dev);
	number++;
	goto get_one_packet;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void bf537mac_poll(struct net_device *dev)
{
	disable_irq(IRQ_MAC_RX);
	bf537mac_interrupt(IRQ_MAC_RX, dev);
	enable_irq(IRQ_MAC_RX);
}
#endif				/* CONFIG_NET_POLL_CONTROLLER */

static void bf537mac_disable(void)
{
	unsigned int opmode;

	opmode = bfin_read_EMAC_OPMODE();
	opmode &= (~RE);
	opmode &= (~TE);
	/* Turn off the EMAC */
	bfin_write_EMAC_OPMODE(opmode);
}

/*
 * Enable Interrupts, Receive, and Transmit
 */
static void bf537mac_enable(void)
{
	u32 opmode;

	pr_debug("%s: %s\n", DRV_NAME, __FUNCTION__);

	/* Set RX DMA */
	bfin_write_DMA1_NEXT_DESC_PTR(&(rx_list_head->desc_a));
	bfin_write_DMA1_CONFIG(rx_list_head->desc_a.config);

	/* Wait MII done */
	mdio_poll();

	/* We enable only RX here */
	/* ASTP   : Enable Automatic Pad Stripping
	   PR     : Promiscuous Mode for test
	   PSF    : Receive frames with total length less than 64 bytes.
	   FDMODE : Full Duplex Mode
	   LB     : Internal Loopback for test
	   RE     : Receiver Enable */
	opmode = bfin_read_EMAC_OPMODE();
	if (opmode & FDMODE)
		opmode |= PSF;
	else
		opmode |= DRO | DC | PSF;
	opmode |= RE;

#if defined(CONFIG_BFIN_MAC_RMII)
	opmode |= RMII; /* For Now only 100MBit are supported */
#ifdef CONFIG_BF_REV_0_2
	opmode |= TE;
#endif
#endif
	/* Turn on the EMAC rx */
	bfin_write_EMAC_OPMODE(opmode);
}

/* Our watchdog timed out. Called by the networking layer */
static void bf537mac_timeout(struct net_device *dev)
{
	pr_debug("%s: %s\n", dev->name, __FUNCTION__);

	bf537mac_disable();

	/* reset tx queue */
	tx_list_tail = tx_list_head->next;

	bf537mac_enable();

	/* We can accept TX packets again */
	dev->trans_start = jiffies;
	netif_wake_queue(dev);
}

/*
 * This routine will, depending on the values passed to it,
 * either make it accept multicast packets, go into
 * promiscuous mode (for TCPDUMP and cousins) or accept
 * a select set of multicast packets
 */
static void bf537mac_set_multicast_list(struct net_device *dev)
{
	u32 sysctl;

	if (dev->flags & IFF_PROMISC) {
		printk(KERN_INFO "%s: set to promisc mode\n", dev->name);
		sysctl = bfin_read_EMAC_OPMODE();
		sysctl |= RAF;
		bfin_write_EMAC_OPMODE(sysctl);
	} else if (dev->flags & IFF_ALLMULTI || dev->mc_count) {
		/* accept all multicast */
		sysctl = bfin_read_EMAC_OPMODE();
		sysctl |= PAM;
		bfin_write_EMAC_OPMODE(sysctl);
	} else {
		/* clear promisc or multicast mode */
		sysctl = bfin_read_EMAC_OPMODE();
		sysctl &= ~(RAF | PAM);
		bfin_write_EMAC_OPMODE(sysctl);
	}
}

/*
 * this puts the device in an inactive state
 */
static void bf537mac_shutdown(struct net_device *dev)
{
	/* Turn off the EMAC */
	bfin_write_EMAC_OPMODE(0x00000000);
	/* Turn off the EMAC RX DMA */
	bfin_write_DMA1_CONFIG(0x0000);
	bfin_write_DMA2_CONFIG(0x0000);
}

/*
 * Open and Initialize the interface
 *
 * Set up everything, reset the card, etc..
 */
static int bf537mac_open(struct net_device *dev)
{
	struct bf537mac_local *lp = netdev_priv(dev);
	int retval;
	pr_debug("%s: %s\n", dev->name, __FUNCTION__);

	/*
	 * Check that the address is valid.  If its not, refuse
	 * to bring the device up.  The user must specify an
	 * address using ifconfig eth0 hw ether xx:xx:xx:xx:xx:xx
	 */
	if (!is_valid_ether_addr(dev->dev_addr)) {
		printk(KERN_WARNING DRV_NAME ": no valid ethernet hw addr\n");
		return -EINVAL;
	}

	/* initial rx and tx list */
	retval = desc_list_init();

	if (retval)
		return retval;

	phy_start(lp->phydev);
	setup_system_regs(dev);
	bf537mac_disable();
	bf537mac_enable();

	pr_debug("hardware init finished\n");
	netif_start_queue(dev);
	netif_carrier_on(dev);

	return 0;
}

/*
 *
 * this makes the board clean up everything that it can
 * and not talk to the outside world.   Caused by
 * an 'ifconfig ethX down'
 */
static int bf537mac_close(struct net_device *dev)
{
	struct bf537mac_local *lp = netdev_priv(dev);
	pr_debug("%s: %s\n", dev->name, __FUNCTION__);

	netif_stop_queue(dev);
	netif_carrier_off(dev);

	phy_stop(lp->phydev);

	/* clear everything */
	bf537mac_shutdown(dev);

	/* free the rx/tx buffers */
	desc_list_free();

	return 0;
}

static int __init bf537mac_probe(struct net_device *dev)
{
	struct bf537mac_local *lp = netdev_priv(dev);
	int retval;
	int i;

	/* Grab the MAC address in the MAC */
	*(__le32 *) (&(dev->dev_addr[0])) = cpu_to_le32(bfin_read_EMAC_ADDRLO());
	*(__le16 *) (&(dev->dev_addr[4])) = cpu_to_le16((u16) bfin_read_EMAC_ADDRHI());

	/* probe mac */
	/*todo: how to proble? which is revision_register */
	bfin_write_EMAC_ADDRLO(0x12345678);
	if (bfin_read_EMAC_ADDRLO() != 0x12345678) {
		pr_debug("can't detect bf537 mac!\n");
		retval = -ENODEV;
		goto err_out;
	}

	/* set the GPIO pins to Ethernet mode */
	retval = setup_pin_mux(1);
	if (retval)
		return retval;

	/*Is it valid? (Did bootloader initialize it?) */
	if (!is_valid_ether_addr(dev->dev_addr)) {
		/* Grab the MAC from the board somehow - this is done in the
		   arch/blackfin/mach-bf537/boards/eth_mac.c */
		bfin_get_ether_addr(dev->dev_addr);
	}

	/* If still not valid, get a random one */
	if (!is_valid_ether_addr(dev->dev_addr)) {
		random_ether_addr(dev->dev_addr);
	}

	setup_mac_addr(dev->dev_addr);

	/* MDIO bus initial */
	lp->mii_bus.priv = dev;
	lp->mii_bus.read = mdiobus_read;
	lp->mii_bus.write = mdiobus_write;
	lp->mii_bus.reset = mdiobus_reset;
	lp->mii_bus.name = "bfin_mac_mdio";
	lp->mii_bus.id = 0;
	lp->mii_bus.irq = kmalloc(sizeof(int)*PHY_MAX_ADDR, GFP_KERNEL);
	for (i = 0; i < PHY_MAX_ADDR; ++i)
		lp->mii_bus.irq[i] = PHY_POLL;

	mdiobus_register(&lp->mii_bus);

	retval = mii_probe(dev);
	if (retval)
		return retval;

	/* Fill in the fields of the device structure with ethernet values. */
	ether_setup(dev);

	dev->open = bf537mac_open;
	dev->stop = bf537mac_close;
	dev->hard_start_xmit = bf537mac_hard_start_xmit;
	dev->set_mac_address = bf537mac_set_mac_address;
	dev->tx_timeout = bf537mac_timeout;
	dev->set_multicast_list = bf537mac_set_multicast_list;
#ifdef CONFIG_NET_POLL_CONTROLLER
	dev->poll_controller = bf537mac_poll;
#endif

	spin_lock_init(&lp->lock);

	/* now, enable interrupts */
	/* register irq handler */
	if (request_irq
	    (IRQ_MAC_RX, bf537mac_interrupt, IRQF_DISABLED | IRQF_SHARED,
	     "BFIN537_MAC_RX", dev)) {
		printk(KERN_WARNING DRV_NAME
		       ": Unable to attach BlackFin MAC RX interrupt\n");
		return -EBUSY;
	}


	retval = register_netdev(dev);
	if (retval == 0) {
		/* now, print out the card info, in a short format.. */
		printk(KERN_INFO "%s: Version %s, %s\n",
			 DRV_NAME, DRV_VERSION, DRV_DESC);
	}

err_out:
	return retval;
}

static int bfin_mac_probe(struct platform_device *pdev)
{
	struct net_device *ndev;

	ndev = alloc_etherdev(sizeof(struct bf537mac_local));
	if (!ndev) {
		printk(KERN_WARNING DRV_NAME ": could not allocate device\n");
		return -ENOMEM;
	}

	SET_NETDEV_DEV(ndev, &pdev->dev);

	platform_set_drvdata(pdev, ndev);

	if (bf537mac_probe(ndev) != 0) {
		platform_set_drvdata(pdev, NULL);
		free_netdev(ndev);
		printk(KERN_WARNING DRV_NAME ": not found\n");
		return -ENODEV;
	}

	return 0;
}

static int bfin_mac_remove(struct platform_device *pdev)
{
	struct net_device *ndev = platform_get_drvdata(pdev);

	platform_set_drvdata(pdev, NULL);

	unregister_netdev(ndev);

	free_irq(IRQ_MAC_RX, ndev);

	free_netdev(ndev);

	setup_pin_mux(0);

	return 0;
}

#ifdef CONFIG_PM
static int bfin_mac_suspend(struct platform_device *pdev, pm_message_t mesg)
{
	struct net_device *net_dev = platform_get_drvdata(pdev);

	if (netif_running(net_dev))
		bf537mac_close(net_dev);

	return 0;
}

static int bfin_mac_resume(struct platform_device *pdev)
{
	struct net_device *net_dev = platform_get_drvdata(pdev);

	if (netif_running(net_dev))
		bf537mac_open(net_dev);

	return 0;
}
#else
#define bfin_mac_suspend NULL
#define bfin_mac_resume NULL
#endif	/* CONFIG_PM */

static struct platform_driver bfin_mac_driver = {
	.probe = bfin_mac_probe,
	.remove = bfin_mac_remove,
	.resume = bfin_mac_resume,
	.suspend = bfin_mac_suspend,
	.driver = {
		   .name = DRV_NAME,
		   },
};

static int __init bfin_mac_init(void)
{
	return platform_driver_register(&bfin_mac_driver);
}

module_init(bfin_mac_init);

static void __exit bfin_mac_cleanup(void)
{
	platform_driver_unregister(&bfin_mac_driver);
}

module_exit(bfin_mac_cleanup);