/*
   * drivers/net/ethernet/netx-eth.c
   *
   * Copyright (c) 2005 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2
   * as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, see <http://www.gnu.org/licenses/>.
   */
  
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/module.h>
  #include <linux/kernel.h>
  #include <linux/delay.h>
  
  #include <linux/netdevice.h>
  #include <linux/platform_device.h>
  #include <linux/etherdevice.h>
  #include <linux/skbuff.h>
  #include <linux/mii.h>
  
  #include <asm/io.h>
  #include <mach/hardware.h>
  #include <mach/netx-regs.h>
  #include <mach/pfifo.h>
  #include <mach/xc.h>
  #include <linux/platform_data/eth-netx.h>
  
  /* XC Fifo Offsets */
  #define EMPTY_PTR_FIFO(xcno)    (0 + ((xcno) << 3))	/* Index of the empty pointer FIFO */
  #define IND_FIFO_PORT_HI(xcno)  (1 + ((xcno) << 3))	/* Index of the FIFO where received */
  							/* Data packages are indicated by XC */
  #define IND_FIFO_PORT_LO(xcno)  (2 + ((xcno) << 3))	/* Index of the FIFO where received */
  							/* Data packages are indicated by XC */
  #define REQ_FIFO_PORT_HI(xcno)  (3 + ((xcno) << 3))	/* Index of the FIFO where Data packages */
  							/* have to be indicated by ARM which */
  							/* shall be sent */
  #define REQ_FIFO_PORT_LO(xcno)  (4 + ((xcno) << 3))	/* Index of the FIFO where Data packages */
  							/* have to be indicated by ARM which shall */
  							/* be sent */
  #define CON_FIFO_PORT_HI(xcno)  (5 + ((xcno) << 3))	/* Index of the FIFO where sent Data packages */
  							/* are confirmed */
  #define CON_FIFO_PORT_LO(xcno)  (6 + ((xcno) << 3))	/* Index of the FIFO where sent Data */
  							/* packages are confirmed */
  #define PFIFO_MASK(xcno)        (0x7f << (xcno*8))
  
  #define FIFO_PTR_FRAMELEN_SHIFT 0
  #define FIFO_PTR_FRAMELEN_MASK  (0x7ff << 0)
  #define FIFO_PTR_FRAMELEN(len)  (((len) << 0) & FIFO_PTR_FRAMELEN_MASK)
  #define FIFO_PTR_TIMETRIG       (1<<11)
  #define FIFO_PTR_MULTI_REQ
  #define FIFO_PTR_ORIGIN         (1<<14)
  #define FIFO_PTR_VLAN           (1<<15)
  #define FIFO_PTR_FRAMENO_SHIFT  16
  #define FIFO_PTR_FRAMENO_MASK   (0x3f << 16)
  #define FIFO_PTR_FRAMENO(no)    (((no) << 16) & FIFO_PTR_FRAMENO_MASK)
  #define FIFO_PTR_SEGMENT_SHIFT  22
  #define FIFO_PTR_SEGMENT_MASK   (0xf << 22)
  #define FIFO_PTR_SEGMENT(seg)   (((seg) & 0xf) << 22)
  #define FIFO_PTR_ERROR_SHIFT    28
  #define FIFO_PTR_ERROR_MASK     (0xf << 28)
  
  #define ISR_LINK_STATUS_CHANGE (1<<4)
  #define ISR_IND_LO             (1<<3)
  #define ISR_CON_LO             (1<<2)
  #define ISR_IND_HI             (1<<1)
  #define ISR_CON_HI             (1<<0)
  
  #define ETH_MAC_LOCAL_CONFIG 0x1560
  #define ETH_MAC_4321         0x1564
  #define ETH_MAC_65           0x1568
  
  #define MAC_TRAFFIC_CLASS_ARRANGEMENT_SHIFT 16
  #define MAC_TRAFFIC_CLASS_ARRANGEMENT_MASK (0xf<<MAC_TRAFFIC_CLASS_ARRANGEMENT_SHIFT)
  #define MAC_TRAFFIC_CLASS_ARRANGEMENT(x) (((x)<<MAC_TRAFFIC_CLASS_ARRANGEMENT_SHIFT) & MAC_TRAFFIC_CLASS_ARRANGEMENT_MASK)
  #define LOCAL_CONFIG_LINK_STATUS_IRQ_EN (1<<24)
  #define LOCAL_CONFIG_CON_LO_IRQ_EN (1<<23)
  #define LOCAL_CONFIG_CON_HI_IRQ_EN (1<<22)
  #define LOCAL_CONFIG_IND_LO_IRQ_EN (1<<21)
  #define LOCAL_CONFIG_IND_HI_IRQ_EN (1<<20)
  
  #define CARDNAME "netx-eth"
  
  /* LSB must be zero */
  #define INTERNAL_PHY_ADR 0x1c
  
  struct netx_eth_priv {
  	void                    __iomem *sram_base, *xpec_base, *xmac_base;
  	int                     id;
  	struct mii_if_info      mii;
  	u32                     msg_enable;
  	struct xc               *xc;
  	spinlock_t              lock;
  };
  
  static void netx_eth_set_multicast_list(struct net_device *ndev)
  {
  	/* implement me */
  }
  
  static int
  netx_eth_hard_start_xmit(struct sk_buff *skb, struct net_device *ndev)
  {
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  	unsigned char *buf = skb->data;
  	unsigned int len = skb->len;
  
  	spin_lock_irq(&priv->lock);
  	memcpy_toio(priv->sram_base + 1560, (void *)buf, len);
  	if (len < 60) {
  		memset_io(priv->sram_base + 1560 + len, 0, 60 - len);
  		len = 60;
  	}
  
  	pfifo_push(REQ_FIFO_PORT_LO(priv->id),
  	           FIFO_PTR_SEGMENT(priv->id) |
  	           FIFO_PTR_FRAMENO(1) |
  	           FIFO_PTR_FRAMELEN(len));
  
  	ndev->stats.tx_packets++;
  	ndev->stats.tx_bytes += skb->len;
  
  	netif_stop_queue(ndev);
  	spin_unlock_irq(&priv->lock);
  	dev_kfree_skb(skb);
  
  	return NETDEV_TX_OK;
  }
  
  static void netx_eth_receive(struct net_device *ndev)
  {
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  	unsigned int val, frameno, seg, len;
  	unsigned char *data;
  	struct sk_buff *skb;
  
  	val = pfifo_pop(IND_FIFO_PORT_LO(priv->id));
  
  	frameno = (val & FIFO_PTR_FRAMENO_MASK) >> FIFO_PTR_FRAMENO_SHIFT;
  	seg = (val & FIFO_PTR_SEGMENT_MASK) >> FIFO_PTR_SEGMENT_SHIFT;
  	len = (val & FIFO_PTR_FRAMELEN_MASK) >> FIFO_PTR_FRAMELEN_SHIFT;
  
  	skb = netdev_alloc_skb(ndev, len);
  	if (unlikely(skb == NULL)) {
  		ndev->stats.rx_dropped++;
  		return;
  	}
  
  	data = skb_put(skb, len);
  
  	memcpy_fromio(data, priv->sram_base + frameno * 1560, len);
  
  	pfifo_push(EMPTY_PTR_FIFO(priv->id),
  		FIFO_PTR_SEGMENT(seg) | FIFO_PTR_FRAMENO(frameno));
  
  	skb->protocol = eth_type_trans(skb, ndev);
  	netif_rx(skb);
  	ndev->stats.rx_packets++;
  	ndev->stats.rx_bytes += len;
  }
  
  static irqreturn_t
  netx_eth_interrupt(int irq, void *dev_id)
  {
  	struct net_device *ndev = dev_id;
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  	int status;
  	unsigned long flags;
  
  	spin_lock_irqsave(&priv->lock, flags);
  
  	status = readl(NETX_PFIFO_XPEC_ISR(priv->id));
  	while (status) {
  		int fill_level;
  		writel(status, NETX_PFIFO_XPEC_ISR(priv->id));
  
  		if ((status & ISR_CON_HI) || (status & ISR_IND_HI))
  			printk("%s: unexpected status: 0x%08x
  ",
  			    __func__, status);
  
  		fill_level =
  		    readl(NETX_PFIFO_FILL_LEVEL(IND_FIFO_PORT_LO(priv->id)));
  		while (fill_level--)
  			netx_eth_receive(ndev);
  
  		if (status & ISR_CON_LO)
  			netif_wake_queue(ndev);
  
  		if (status & ISR_LINK_STATUS_CHANGE)
  			mii_check_media(&priv->mii, netif_msg_link(priv), 1);
  
  		status = readl(NETX_PFIFO_XPEC_ISR(priv->id));
  	}
  	spin_unlock_irqrestore(&priv->lock, flags);
  	return IRQ_HANDLED;
  }
  
  static int netx_eth_open(struct net_device *ndev)
  {
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  
  	if (request_irq
  	    (ndev->irq, netx_eth_interrupt, IRQF_SHARED, ndev->name, ndev))
  		return -EAGAIN;
  
  	writel(ndev->dev_addr[0] |
  	       ndev->dev_addr[1]<<8 |
  	       ndev->dev_addr[2]<<16 |
  	       ndev->dev_addr[3]<<24,
  	       priv->xpec_base + NETX_XPEC_RAM_START_OFS + ETH_MAC_4321);
  	writel(ndev->dev_addr[4] |
  	       ndev->dev_addr[5]<<8,
  	       priv->xpec_base + NETX_XPEC_RAM_START_OFS + ETH_MAC_65);
  
  	writel(LOCAL_CONFIG_LINK_STATUS_IRQ_EN |
  		LOCAL_CONFIG_CON_LO_IRQ_EN |
  		LOCAL_CONFIG_CON_HI_IRQ_EN |
  		LOCAL_CONFIG_IND_LO_IRQ_EN |
  		LOCAL_CONFIG_IND_HI_IRQ_EN,
  		priv->xpec_base + NETX_XPEC_RAM_START_OFS +
  		ETH_MAC_LOCAL_CONFIG);
  
  	mii_check_media(&priv->mii, netif_msg_link(priv), 1);
  	netif_start_queue(ndev);
  
  	return 0;
  }
  
  static int netx_eth_close(struct net_device *ndev)
  {
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  
  	netif_stop_queue(ndev);
  
  	writel(0,
  	    priv->xpec_base + NETX_XPEC_RAM_START_OFS + ETH_MAC_LOCAL_CONFIG);
  
  	free_irq(ndev->irq, ndev);
  
  	return 0;
  }
  
  static void netx_eth_timeout(struct net_device *ndev)
  {
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  	int i;
  
  	printk(KERN_ERR "%s: transmit timed out, resetting
  ", ndev->name);
  
  	spin_lock_irq(&priv->lock);
  
  	xc_reset(priv->xc);
  	xc_start(priv->xc);
  
  	for (i=2; i<=18; i++)
  		pfifo_push(EMPTY_PTR_FIFO(priv->id),
  			FIFO_PTR_FRAMENO(i) | FIFO_PTR_SEGMENT(priv->id));
  
  	spin_unlock_irq(&priv->lock);
  
  	netif_wake_queue(ndev);
  }
  
  static int
  netx_eth_phy_read(struct net_device *ndev, int phy_id, int reg)
  {
  	unsigned int val;
  
  	val = MIIMU_SNRDY | MIIMU_PREAMBLE | MIIMU_PHYADDR(phy_id) |
  	      MIIMU_REGADDR(reg) | MIIMU_PHY_NRES;
  
  	writel(val, NETX_MIIMU);
  	while (readl(NETX_MIIMU) & MIIMU_SNRDY);
  
  	return readl(NETX_MIIMU) >> 16;
  
  }
  
  static void
  netx_eth_phy_write(struct net_device *ndev, int phy_id, int reg, int value)
  {
  	unsigned int val;
  
  	val = MIIMU_SNRDY | MIIMU_PREAMBLE | MIIMU_PHYADDR(phy_id) |
  	      MIIMU_REGADDR(reg) | MIIMU_PHY_NRES | MIIMU_OPMODE_WRITE |
  	      MIIMU_DATA(value);
  
  	writel(val, NETX_MIIMU);
  	while (readl(NETX_MIIMU) & MIIMU_SNRDY);
  }
  
  static const struct net_device_ops netx_eth_netdev_ops = {
  	.ndo_open		= netx_eth_open,
  	.ndo_stop		= netx_eth_close,
  	.ndo_start_xmit		= netx_eth_hard_start_xmit,
  	.ndo_tx_timeout		= netx_eth_timeout,
  	.ndo_set_rx_mode	= netx_eth_set_multicast_list,
  	.ndo_change_mtu		= eth_change_mtu,
  	.ndo_validate_addr	= eth_validate_addr,
  	.ndo_set_mac_address	= eth_mac_addr,
  };
  
  static int netx_eth_enable(struct net_device *ndev)
  {
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  	unsigned int mac4321, mac65;
  	int running, i;
  
  	ether_setup(ndev);
  
  	ndev->netdev_ops = &netx_eth_netdev_ops;
  	ndev->watchdog_timeo = msecs_to_jiffies(5000);
  
  	priv->msg_enable       = NETIF_MSG_LINK;
  	priv->mii.phy_id_mask  = 0x1f;
  	priv->mii.reg_num_mask = 0x1f;
  	priv->mii.force_media  = 0;
  	priv->mii.full_duplex  = 0;
  	priv->mii.dev	     = ndev;
  	priv->mii.mdio_read    = netx_eth_phy_read;
  	priv->mii.mdio_write   = netx_eth_phy_write;
  	priv->mii.phy_id = INTERNAL_PHY_ADR + priv->id;
  
  	running = xc_running(priv->xc);
  	xc_stop(priv->xc);
  
  	/* if the xc engine is already running, assume the bootloader has
  	 * loaded the firmware for us
  	 */
  	if (running) {
  		/* get Node Address from hardware */
  		mac4321 = readl(priv->xpec_base +
  			NETX_XPEC_RAM_START_OFS + ETH_MAC_4321);
  		mac65 = readl(priv->xpec_base +
  			NETX_XPEC_RAM_START_OFS + ETH_MAC_65);
  
  		ndev->dev_addr[0] = mac4321 & 0xff;
  		ndev->dev_addr[1] = (mac4321 >> 8) & 0xff;
  		ndev->dev_addr[2] = (mac4321 >> 16) & 0xff;
  		ndev->dev_addr[3] = (mac4321 >> 24) & 0xff;
  		ndev->dev_addr[4] = mac65 & 0xff;
  		ndev->dev_addr[5] = (mac65 >> 8) & 0xff;
  	} else {
  		if (xc_request_firmware(priv->xc)) {
  			printk(CARDNAME ": requesting firmware failed
  ");
  			return -ENODEV;
  		}
  	}
  
  	xc_reset(priv->xc);
  	xc_start(priv->xc);
  
  	if (!is_valid_ether_addr(ndev->dev_addr))
  		printk("%s: Invalid ethernet MAC address.  Please "
  		       "set using ifconfig
  ", ndev->name);
  
  	for (i=2; i<=18; i++)
  		pfifo_push(EMPTY_PTR_FIFO(priv->id),
  			FIFO_PTR_FRAMENO(i) | FIFO_PTR_SEGMENT(priv->id));
  
  	return register_netdev(ndev);
  
  }
  
  static int netx_eth_drv_probe(struct platform_device *pdev)
  {
  	struct netx_eth_priv *priv;
  	struct net_device *ndev;
  	struct netxeth_platform_data *pdata;
  	int ret;
  
  	ndev = alloc_etherdev(sizeof (struct netx_eth_priv));
  	if (!ndev) {
  		ret = -ENOMEM;
  		goto exit;
  	}
  	SET_NETDEV_DEV(ndev, &pdev->dev);
  
  	platform_set_drvdata(pdev, ndev);
  
  	priv = netdev_priv(ndev);
  
  	pdata = dev_get_platdata(&pdev->dev);
  	priv->xc = request_xc(pdata->xcno, &pdev->dev);
  	if (!priv->xc) {
  		dev_err(&pdev->dev, "unable to request xc engine
  ");
  		ret = -ENODEV;
  		goto exit_free_netdev;
  	}
  
  	ndev->irq = priv->xc->irq;
  	priv->id = pdev->id;
  	priv->xpec_base = priv->xc->xpec_base;
  	priv->xmac_base = priv->xc->xmac_base;
  	priv->sram_base = priv->xc->sram_base;
  
  	spin_lock_init(&priv->lock);
  
  	ret = pfifo_request(PFIFO_MASK(priv->id));
  	if (ret) {
  		printk("unable to request PFIFO
  ");
  		goto exit_free_xc;
  	}
  
  	ret = netx_eth_enable(ndev);
  	if (ret)
  		goto exit_free_pfifo;
  
  	return 0;
  exit_free_pfifo:
  	pfifo_free(PFIFO_MASK(priv->id));
  exit_free_xc:
  	free_xc(priv->xc);
  exit_free_netdev:
  	free_netdev(ndev);
  exit:
  	return ret;
  }
  
  static int netx_eth_drv_remove(struct platform_device *pdev)
  {
  	struct net_device *ndev = platform_get_drvdata(pdev);
  	struct netx_eth_priv *priv = netdev_priv(ndev);
  
  	unregister_netdev(ndev);
  	xc_stop(priv->xc);
  	free_xc(priv->xc);
  	free_netdev(ndev);
  	pfifo_free(PFIFO_MASK(priv->id));
  
  	return 0;
  }
  
  static int netx_eth_drv_suspend(struct platform_device *pdev, pm_message_t state)
  {
  	dev_err(&pdev->dev, "suspend not implemented
  ");
  	return 0;
  }
  
  static int netx_eth_drv_resume(struct platform_device *pdev)
  {
  	dev_err(&pdev->dev, "resume not implemented
  ");
  	return 0;
  }
  
  static struct platform_driver netx_eth_driver = {
  	.probe		= netx_eth_drv_probe,
  	.remove		= netx_eth_drv_remove,
  	.suspend	= netx_eth_drv_suspend,
  	.resume		= netx_eth_drv_resume,
  	.driver		= {
  		.name	= CARDNAME,
  		.owner	= THIS_MODULE,
  	},
  };
  
  static int __init netx_eth_init(void)
  {
  	unsigned int phy_control, val;
  
  	printk("NetX Ethernet driver
  ");
  
  	phy_control = PHY_CONTROL_PHY_ADDRESS(INTERNAL_PHY_ADR>>1) |
  		      PHY_CONTROL_PHY1_MODE(PHY_MODE_ALL) |
  		      PHY_CONTROL_PHY1_AUTOMDIX |
  		      PHY_CONTROL_PHY1_EN |
  		      PHY_CONTROL_PHY0_MODE(PHY_MODE_ALL) |
  		      PHY_CONTROL_PHY0_AUTOMDIX |
  		      PHY_CONTROL_PHY0_EN |
  		      PHY_CONTROL_CLK_XLATIN;
  
  	val = readl(NETX_SYSTEM_IOC_ACCESS_KEY);
  	writel(val, NETX_SYSTEM_IOC_ACCESS_KEY);
  
  	writel(phy_control | PHY_CONTROL_RESET, NETX_SYSTEM_PHY_CONTROL);
  	udelay(100);
  
  	val = readl(NETX_SYSTEM_IOC_ACCESS_KEY);
  	writel(val, NETX_SYSTEM_IOC_ACCESS_KEY);
  
  	writel(phy_control, NETX_SYSTEM_PHY_CONTROL);
  
  	return platform_driver_register(&netx_eth_driver);
  }
  
  static void __exit netx_eth_cleanup(void)
  {
  	platform_driver_unregister(&netx_eth_driver);
  }
  
  module_init(netx_eth_init);
  module_exit(netx_eth_cleanup);
  
  MODULE_AUTHOR("Sascha Hauer, Pengutronix");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS("platform:" CARDNAME);
  MODULE_FIRMWARE("xc0.bin");
  MODULE_FIRMWARE("xc1.bin");
  MODULE_FIRMWARE("xc2.bin");