drivers/net/xilinx_emaclite.c - platform/external/u-boot - Gitiles

 /*
  * (C) Copyright 2007-2009 Michal Simek
  * (C) Copyright 2003 Xilinx Inc.
  *
  * Michal SIMEK <monstr@monstr.eu>
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */

 #include <common.h>
 #include <net.h>
 #include <config.h>
 #include <dm.h>
 #include <console.h>
 #include <malloc.h>
 #include <asm/io.h>
 #include <phy.h>
 #include <miiphy.h>
 #include <fdtdec.h>
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <asm/io.h>

 DECLARE_GLOBAL_DATA_PTR;

 #define ENET_ADDR_LENGTH	6
 #define ETH_FCS_LEN		4 /* Octets in the FCS */

 /* Xmit complete */
 #define XEL_TSR_XMIT_BUSY_MASK		0x00000001UL
 /* Xmit interrupt enable bit */
 #define XEL_TSR_XMIT_IE_MASK		0x00000008UL
 /* Program the MAC address */
 #define XEL_TSR_PROGRAM_MASK		0x00000002UL
 /* define for programming the MAC address into the EMAC Lite */
 #define XEL_TSR_PROG_MAC_ADDR	(XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_PROGRAM_MASK)

 /* Transmit packet length upper byte */
 #define XEL_TPLR_LENGTH_MASK_HI		0x0000FF00UL
 /* Transmit packet length lower byte */
 #define XEL_TPLR_LENGTH_MASK_LO		0x000000FFUL

 /* Recv complete */
 #define XEL_RSR_RECV_DONE_MASK		0x00000001UL
 /* Recv interrupt enable bit */
 #define XEL_RSR_RECV_IE_MASK		0x00000008UL

 /* MDIO Address Register Bit Masks */
 #define XEL_MDIOADDR_REGADR_MASK  0x0000001F	/* Register Address */
 #define XEL_MDIOADDR_PHYADR_MASK  0x000003E0	/* PHY Address */
 #define XEL_MDIOADDR_PHYADR_SHIFT 5
 #define XEL_MDIOADDR_OP_MASK	  0x00000400	/* RD/WR Operation */

 /* MDIO Write Data Register Bit Masks */
 #define XEL_MDIOWR_WRDATA_MASK	  0x0000FFFF	/* Data to be Written */

 /* MDIO Read Data Register Bit Masks */
 #define XEL_MDIORD_RDDATA_MASK	  0x0000FFFF	/* Data to be Read */

 /* MDIO Control Register Bit Masks */
 #define XEL_MDIOCTRL_MDIOSTS_MASK 0x00000001	/* MDIO Status Mask */
 #define XEL_MDIOCTRL_MDIOEN_MASK  0x00000008	/* MDIO Enable */

 struct emaclite_regs {
 	u32 tx_ping; /* 0x0 - TX Ping buffer */
 	u32 reserved1[504];
 	u32 mdioaddr; /* 0x7e4 - MDIO Address Register */
 	u32 mdiowr; /* 0x7e8 - MDIO Write Data Register */
 	u32 mdiord;/* 0x7ec - MDIO Read Data Register */
 	u32 mdioctrl; /* 0x7f0 - MDIO Control Register */
 	u32 tx_ping_tplr; /* 0x7f4 - Tx packet length */
 	u32 global_interrupt; /* 0x7f8 - Global interrupt enable */
 	u32 tx_ping_tsr; /* 0x7fc - Tx status */
 	u32 tx_pong; /* 0x800 - TX Pong buffer */
 	u32 reserved2[508];
 	u32 tx_pong_tplr; /* 0xff4 - Tx packet length */
 	u32 reserved3; /* 0xff8 */
 	u32 tx_pong_tsr; /* 0xffc - Tx status */
 	u32 rx_ping; /* 0x1000 - Receive Buffer */
 	u32 reserved4[510];
 	u32 rx_ping_rsr; /* 0x17fc - Rx status */
 	u32 rx_pong; /* 0x1800 - Receive Buffer */
 	u32 reserved5[510];
 	u32 rx_pong_rsr; /* 0x1ffc - Rx status */
 };

 struct xemaclite {
 	bool use_rx_pong_buffer_next;	/* Next RX buffer to read from */
 	u32 txpp;		/* TX ping pong buffer */
 	u32 rxpp;		/* RX ping pong buffer */
 	int phyaddr;
 	struct emaclite_regs *regs;
 	struct phy_device *phydev;
 	struct mii_dev *bus;
 };

 static uchar etherrxbuff[PKTSIZE_ALIGN]; /* Receive buffer */

 static void xemaclite_alignedread(u32 *srcptr, void *destptr, u32 bytecount)
 {
 	u32 i;
 	u32 alignbuffer;
 	u32 *to32ptr;
 	u32 *from32ptr;
 	u8 *to8ptr;
 	u8 *from8ptr;

 	from32ptr = (u32 *) srcptr;

 	/* Word aligned buffer, no correction needed. */
 	to32ptr = (u32 *) destptr;
 	while (bytecount > 3) {
 		*to32ptr++ = *from32ptr++;
 		bytecount -= 4;
 	}
 	to8ptr = (u8 *) to32ptr;

 	alignbuffer = *from32ptr++;
 	from8ptr = (u8 *) &alignbuffer;

 	for (i = 0; i < bytecount; i++)
 		*to8ptr++ = *from8ptr++;
 }

 static void xemaclite_alignedwrite(void *srcptr, u32 *destptr, u32 bytecount)
 {
 	u32 i;
 	u32 alignbuffer;
 	u32 *to32ptr = (u32 *) destptr;
 	u32 *from32ptr;
 	u8 *to8ptr;
 	u8 *from8ptr;

 	from32ptr = (u32 *) srcptr;
 	while (bytecount > 3) {

 		*to32ptr++ = *from32ptr++;
 		bytecount -= 4;
 	}

 	alignbuffer = 0;
 	to8ptr = (u8 *) &alignbuffer;
 	from8ptr = (u8 *) from32ptr;

 	for (i = 0; i < bytecount; i++)
 		*to8ptr++ = *from8ptr++;

 	*to32ptr++ = alignbuffer;
 }

 static int wait_for_bit(const char *func, u32 *reg, const u32 mask,
 			bool set, unsigned int timeout)
 {
 	u32 val;
 	unsigned long start = get_timer(0);

 	while (1) {
 		val = __raw_readl(reg);

 		if (!set)
 			val = ~val;

 		if ((val & mask) == mask)
 			return 0;

 		if (get_timer(start) > timeout)
 			break;

 		if (ctrlc()) {
 			puts("Abort\n");
 			return -EINTR;
 		}

 		udelay(1);
 	}

 	debug("%s: Timeout (reg=%p mask=%08x wait_set=%i)\n",
 	      func, reg, mask, set);

 	return -ETIMEDOUT;
 }

 static int mdio_wait(struct emaclite_regs *regs)
 {
 	return wait_for_bit(__func__, &regs->mdioctrl,
 			    XEL_MDIOCTRL_MDIOSTS_MASK, false, 2000);
 }

 static u32 phyread(struct xemaclite *emaclite, u32 phyaddress, u32 registernum,
 		   u16 *data)
 {
 	struct emaclite_regs *regs = emaclite->regs;

 	if (mdio_wait(regs))
 		return 1;

 	u32 ctrl_reg = __raw_readl(&regs->mdioctrl);
 	__raw_writel(XEL_MDIOADDR_OP_MASK
 		| ((phyaddress << XEL_MDIOADDR_PHYADR_SHIFT)
 		| registernum), &regs->mdioaddr);
 	__raw_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK, &regs->mdioctrl);

 	if (mdio_wait(regs))
 		return 1;

 	/* Read data */
 	*data = __raw_readl(&regs->mdiord);
 	return 0;
 }

 static u32 phywrite(struct xemaclite *emaclite, u32 phyaddress, u32 registernum,
 		    u16 data)
 {
 	struct emaclite_regs *regs = emaclite->regs;

 	if (mdio_wait(regs))
 		return 1;

 	/*
 	 * Write the PHY address, register number and clear the OP bit in the
 	 * MDIO Address register and then write the value into the MDIO Write
 	 * Data register. Finally, set the Status bit in the MDIO Control
 	 * register to start a MDIO write transaction.
 	 */
 	u32 ctrl_reg = __raw_readl(&regs->mdioctrl);
 	__raw_writel(~XEL_MDIOADDR_OP_MASK
 		& ((phyaddress << XEL_MDIOADDR_PHYADR_SHIFT)
 		| registernum), &regs->mdioaddr);
 	__raw_writel(data, &regs->mdiowr);
 	__raw_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK, &regs->mdioctrl);

 	if (mdio_wait(regs))
 		return 1;

 	return 0;
 }

 static void emaclite_stop(struct udevice *dev)
 {
 	debug("eth_stop\n");
 }

 /* Use MII register 1 (MII status register) to detect PHY */
 #define PHY_DETECT_REG  1

 /* Mask used to verify certain PHY features (or register contents)
  * in the register above:
  *  0x1000: 10Mbps full duplex support
  *  0x0800: 10Mbps half duplex support
  *  0x0008: Auto-negotiation support
  */
 #define PHY_DETECT_MASK 0x1808

 static int setup_phy(struct udevice *dev)
 {
 	int i, ret;
 	u16 phyreg;
 	struct xemaclite *emaclite = dev_get_priv(dev);
 	struct phy_device *phydev;

 	u32 supported = SUPPORTED_10baseT_Half |
 			SUPPORTED_10baseT_Full |
 			SUPPORTED_100baseT_Half |
 			SUPPORTED_100baseT_Full;

 	if (emaclite->phyaddr != -1) {
 		phyread(emaclite, emaclite->phyaddr, PHY_DETECT_REG, &phyreg);
 		if ((phyreg != 0xFFFF) &&
 		    ((phyreg & PHY_DETECT_MASK) == PHY_DETECT_MASK)) {
 			/* Found a valid PHY address */
 			debug("Default phy address %d is valid\n",
 			      emaclite->phyaddr);
 		} else {
 			debug("PHY address is not setup correctly %d\n",
 			      emaclite->phyaddr);
 			emaclite->phyaddr = -1;
 		}
 	}

 	if (emaclite->phyaddr == -1) {
 		/* detect the PHY address */
 		for (i = 31; i >= 0; i--) {
 			phyread(emaclite, i, PHY_DETECT_REG, &phyreg);
 			if ((phyreg != 0xFFFF) &&
 			    ((phyreg & PHY_DETECT_MASK) == PHY_DETECT_MASK)) {
 				/* Found a valid PHY address */
 				emaclite->phyaddr = i;
 				debug("emaclite: Found valid phy address, %d\n",
 				      i);
 				break;
 			}
 		}
 	}

 	/* interface - look at tsec */
 	phydev = phy_connect(emaclite->bus, emaclite->phyaddr, dev,
 			     PHY_INTERFACE_MODE_MII);
 	/*
 	 * Phy can support 1000baseT but device NOT that's why phydev->supported
 	 * must be setup for 1000baseT. phydev->advertising setups what speeds
 	 * will be used for autonegotiation where 1000baseT must be disabled.
 	 */
 	phydev->supported = supported | SUPPORTED_1000baseT_Half |
 						SUPPORTED_1000baseT_Full;
 	phydev->advertising = supported;
 	emaclite->phydev = phydev;
 	phy_config(phydev);
 	ret = phy_startup(phydev);
 	if (ret)
 		return ret;

 	if (!phydev->link) {
 		printf("%s: No link.\n", phydev->dev->name);
 		return 0;
 	}

 	/* Do not setup anything */
 	return 1;
 }

 static int emaclite_start(struct udevice *dev)
 {
 	struct xemaclite *emaclite = dev_get_priv(dev);
 	struct eth_pdata *pdata = dev_get_platdata(dev);
 	struct emaclite_regs *regs = emaclite->regs;

 	debug("EmacLite Initialization Started\n");

 /*
  * TX - TX_PING & TX_PONG initialization
  */
 	/* Restart PING TX */
 	__raw_writel(0, &regs->tx_ping_tsr);
 	/* Copy MAC address */
 	xemaclite_alignedwrite(pdata->enetaddr, &regs->tx_ping,
 			       ENET_ADDR_LENGTH);
 	/* Set the length */
 	__raw_writel(ENET_ADDR_LENGTH, &regs->tx_ping_tplr);
 	/* Update the MAC address in the EMAC Lite */
 	__raw_writel(XEL_TSR_PROG_MAC_ADDR, &regs->tx_ping_tsr);
 	/* Wait for EMAC Lite to finish with the MAC address update */
 	while ((__raw_readl(&regs->tx_ping_tsr) &
 		XEL_TSR_PROG_MAC_ADDR) != 0)
 		;

 	if (emaclite->txpp) {
 		/* The same operation with PONG TX */
 		__raw_writel(0, &regs->tx_pong_tsr);
 		xemaclite_alignedwrite(pdata->enetaddr, &regs->tx_pong,
 				       ENET_ADDR_LENGTH);
 		__raw_writel(ENET_ADDR_LENGTH, &regs->tx_pong_tplr);
 		__raw_writel(XEL_TSR_PROG_MAC_ADDR, &regs->tx_pong_tsr);
 		while ((__raw_readl(&regs->tx_pong_tsr) &
 		       XEL_TSR_PROG_MAC_ADDR) != 0)
 			;
 	}

 /*
  * RX - RX_PING & RX_PONG initialization
  */
 	/* Write out the value to flush the RX buffer */
 	__raw_writel(XEL_RSR_RECV_IE_MASK, &regs->rx_ping_rsr);

 	if (emaclite->rxpp)
 		__raw_writel(XEL_RSR_RECV_IE_MASK, &regs->rx_pong_rsr);

 	__raw_writel(XEL_MDIOCTRL_MDIOEN_MASK, &regs->mdioctrl);
 	if (__raw_readl(&regs->mdioctrl) & XEL_MDIOCTRL_MDIOEN_MASK)
 		if (!setup_phy(dev))
 			return -1;

 	debug("EmacLite Initialization complete\n");
 	return 0;
 }

 static int xemaclite_txbufferavailable(struct xemaclite *emaclite)
 {
 	u32 tmp;
 	struct emaclite_regs *regs = emaclite->regs;

 	/*
 	 * Read the other buffer register
 	 * and determine if the other buffer is available
 	 */
 	tmp = ~__raw_readl(&regs->tx_ping_tsr);
 	if (emaclite->txpp)
 		tmp |= ~__raw_readl(&regs->tx_pong_tsr);

 	return !(tmp & XEL_TSR_XMIT_BUSY_MASK);
 }

 static int emaclite_send(struct udevice *dev, void *ptr, int len)
 {
 	u32 reg;
 	struct xemaclite *emaclite = dev_get_priv(dev);
 	struct emaclite_regs *regs = emaclite->regs;

 	u32 maxtry = 1000;

 	if (len > PKTSIZE)
 		len = PKTSIZE;

 	while (xemaclite_txbufferavailable(emaclite) && maxtry) {
 		udelay(10);
 		maxtry--;
 	}

 	if (!maxtry) {
 		printf("Error: Timeout waiting for ethernet TX buffer\n");
 		/* Restart PING TX */
 		__raw_writel(0, &regs->tx_ping_tsr);
 		if (emaclite->txpp) {
 			__raw_writel(0, &regs->tx_pong_tsr);
 		}
 		return -1;
 	}

 	/* Determine if the expected buffer address is empty */
 	reg = __raw_readl(&regs->tx_ping_tsr);
 	if ((reg & XEL_TSR_XMIT_BUSY_MASK) == 0) {
 		debug("Send packet from tx_ping buffer\n");
 		/* Write the frame to the buffer */
 		xemaclite_alignedwrite(ptr, &regs->tx_ping, len);
 		__raw_writel(len
 			& (XEL_TPLR_LENGTH_MASK_HI | XEL_TPLR_LENGTH_MASK_LO),
 		       &regs->tx_ping_tplr);
 		reg = __raw_readl(&regs->tx_ping_tsr);
 		reg |= XEL_TSR_XMIT_BUSY_MASK;
 		__raw_writel(reg, &regs->tx_ping_tsr);
 		return 0;
 	}

 	if (emaclite->txpp) {
 		/* Determine if the expected buffer address is empty */
 		reg = __raw_readl(&regs->tx_pong_tsr);
 		if ((reg & XEL_TSR_XMIT_BUSY_MASK) == 0) {
 			debug("Send packet from tx_pong buffer\n");
 			/* Write the frame to the buffer */
 			xemaclite_alignedwrite(ptr, &regs->tx_pong, len);
 			__raw_writel(len &
 				 (XEL_TPLR_LENGTH_MASK_HI |
 				  XEL_TPLR_LENGTH_MASK_LO),
 				  &regs->tx_pong_tplr);
 			reg = __raw_readl(&regs->tx_pong_tsr);
 			reg |= XEL_TSR_XMIT_BUSY_MASK;
 			__raw_writel(reg, &regs->tx_pong_tsr);
 			return 0;
 		}
 	}

 	puts("Error while sending frame\n");
 	return -1;
 }

 static int emaclite_recv(struct udevice *dev, int flags, uchar **packetp)
 {
 	u32 length, first_read, reg, attempt = 0;
 	void *addr, *ack;
 	struct xemaclite *emaclite = dev->priv;
 	struct emaclite_regs *regs = emaclite->regs;
 	struct ethernet_hdr *eth;
 	struct ip_udp_hdr *ip;

 try_again:
 	if (!emaclite->use_rx_pong_buffer_next) {
 		reg = __raw_readl(&regs->rx_ping_rsr);
 		debug("Testing data at rx_ping\n");
 		if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
 			debug("Data found in rx_ping buffer\n");
 			addr = &regs->rx_ping;
 			ack = &regs->rx_ping_rsr;
 		} else {
 			debug("Data not found in rx_ping buffer\n");
 			/* Pong buffer is not available - return immediately */
 			if (!emaclite->rxpp)
 				return -1;

 			/* Try pong buffer if this is first attempt */
 			if (attempt++)
 				return -1;
 			emaclite->use_rx_pong_buffer_next =
 					!emaclite->use_rx_pong_buffer_next;
 			goto try_again;
 		}
 	} else {
 		reg = __raw_readl(&regs->rx_pong_rsr);
 		debug("Testing data at rx_pong\n");
 		if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
 			debug("Data found in rx_pong buffer\n");
 			addr = &regs->rx_pong;
 			ack = &regs->rx_pong_rsr;
 		} else {
 			debug("Data not found in rx_pong buffer\n");
 			/* Try ping buffer if this is first attempt */
 			if (attempt++)
 				return -1;
 			emaclite->use_rx_pong_buffer_next =
 					!emaclite->use_rx_pong_buffer_next;
 			goto try_again;
 		}
 	}

 	/* Read all bytes for ARP packet with 32bit alignment - 48bytes  */
 	first_read = ALIGN(ETHER_HDR_SIZE + ARP_HDR_SIZE + ETH_FCS_LEN, 4);
 	xemaclite_alignedread(addr, etherrxbuff, first_read);

 	/* Detect real packet size */
 	eth = (struct ethernet_hdr *)etherrxbuff;
 	switch (ntohs(eth->et_protlen)) {
 	case PROT_ARP:
 		length = first_read;
 		debug("ARP Packet %x\n", length);
 		break;
 	case PROT_IP:
 		ip = (struct ip_udp_hdr *)(etherrxbuff + ETHER_HDR_SIZE);
 		length = ntohs(ip->ip_len);
 		length += ETHER_HDR_SIZE + ETH_FCS_LEN;
 		debug("IP Packet %x\n", length);
 		break;
 	default:
 		debug("Other Packet\n");
 		length = PKTSIZE;
 		break;
 	}

 	/* Read the rest of the packet which is longer then first read */
 	if (length != first_read)
 		xemaclite_alignedread(addr + first_read,
 				      etherrxbuff + first_read,
 				      length - first_read);

 	/* Acknowledge the frame */
 	reg = __raw_readl(ack);
 	reg &= ~XEL_RSR_RECV_DONE_MASK;
 	__raw_writel(reg, ack);

 	debug("Packet receive from 0x%p, length %dB\n", addr, length);
 	*packetp = etherrxbuff;
 	return length;
 }

 static int emaclite_miiphy_read(struct mii_dev *bus, int addr,
 				int devad, int reg)
 {
 	u32 ret;
 	u16 val = 0;

 	ret = phyread(bus->priv, addr, reg, &val);
 	debug("emaclite: Read MII 0x%x, 0x%x, 0x%x, %d\n", addr, reg, val, ret);
 	return val;
 }

 static int emaclite_miiphy_write(struct mii_dev *bus, int addr, int devad,
 				 int reg, u16 value)
 {
 	debug("emaclite: Write MII 0x%x, 0x%x, 0x%x\n", addr, reg, value);
 	return phywrite(bus->priv, addr, reg, value);
 }

 static int emaclite_probe(struct udevice *dev)
 {
 	struct xemaclite *emaclite = dev_get_priv(dev);
 	int ret;

 	emaclite->bus = mdio_alloc();
 	emaclite->bus->read = emaclite_miiphy_read;
 	emaclite->bus->write = emaclite_miiphy_write;
 	emaclite->bus->priv = emaclite;

 	ret = mdio_register_seq(emaclite->bus, dev->seq);
 	if (ret)
 		return ret;

 	return 0;
 }

 static int emaclite_remove(struct udevice *dev)
 {
 	struct xemaclite *emaclite = dev_get_priv(dev);

 	free(emaclite->phydev);
 	mdio_unregister(emaclite->bus);
 	mdio_free(emaclite->bus);

 	return 0;
 }

 static const struct eth_ops emaclite_ops = {
 	.start = emaclite_start,
 	.send = emaclite_send,
 	.recv = emaclite_recv,
 	.stop = emaclite_stop,
 };

 static int emaclite_ofdata_to_platdata(struct udevice *dev)
 {
 	struct eth_pdata *pdata = dev_get_platdata(dev);
 	struct xemaclite *emaclite = dev_get_priv(dev);
 	int offset = 0;

 	pdata->iobase = (phys_addr_t)dev_get_addr(dev);
 	emaclite->regs = (struct emaclite_regs *)ioremap_nocache(pdata->iobase,
 								 0x10000);

 	emaclite->phyaddr = -1;

 	offset = fdtdec_lookup_phandle(gd->fdt_blob, dev_of_offset(dev),
 				      "phy-handle");
 	if (offset > 0)
 		emaclite->phyaddr = fdtdec_get_int(gd->fdt_blob, offset,
 						   "reg", -1);

 	emaclite->txpp = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
 					"xlnx,tx-ping-pong", 0);
 	emaclite->rxpp = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
 					"xlnx,rx-ping-pong", 0);

 	printf("EMACLITE: %lx, phyaddr %d, %d/%d\n", (ulong)emaclite->regs,
 	       emaclite->phyaddr, emaclite->txpp, emaclite->rxpp);

 	return 0;
 }

 static const struct udevice_id emaclite_ids[] = {
 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a" },
 	{ }
 };

 U_BOOT_DRIVER(emaclite) = {
 	.name   = "emaclite",
 	.id     = UCLASS_ETH,
 	.of_match = emaclite_ids,
 	.ofdata_to_platdata = emaclite_ofdata_to_platdata,
 	.probe  = emaclite_probe,
 	.remove = emaclite_remove,
 	.ops    = &emaclite_ops,
 	.priv_auto_alloc_size = sizeof(struct xemaclite),
 	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
 };
	/*
	* (C) Copyright 2007-2009 Michal Simek
	* (C) Copyright 2003 Xilinx Inc.
	*
	* Michal SIMEK <monstr@monstr.eu>
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/

	#include <common.h>
	#include <net.h>
	#include <config.h>
	#include <dm.h>
	#include <console.h>
	#include <malloc.h>
	#include <asm/io.h>
	#include <phy.h>
	#include <miiphy.h>
	#include <fdtdec.h>
	#include <linux/errno.h>
	#include <linux/kernel.h>
	#include <asm/io.h>

	DECLARE_GLOBAL_DATA_PTR;

	#define ENET_ADDR_LENGTH 6
	#define ETH_FCS_LEN 4 /* Octets in the FCS */

	/* Xmit complete */
	#define XEL_TSR_XMIT_BUSY_MASK 0x00000001UL
	/* Xmit interrupt enable bit */
	#define XEL_TSR_XMIT_IE_MASK 0x00000008UL
	/* Program the MAC address */
	#define XEL_TSR_PROGRAM_MASK 0x00000002UL
	/* define for programming the MAC address into the EMAC Lite */
	#define XEL_TSR_PROG_MAC_ADDR (XEL_TSR_XMIT_BUSY_MASK \| XEL_TSR_PROGRAM_MASK)

	/* Transmit packet length upper byte */
	#define XEL_TPLR_LENGTH_MASK_HI 0x0000FF00UL
	/* Transmit packet length lower byte */
	#define XEL_TPLR_LENGTH_MASK_LO 0x000000FFUL

	/* Recv complete */
	#define XEL_RSR_RECV_DONE_MASK 0x00000001UL
	/* Recv interrupt enable bit */
	#define XEL_RSR_RECV_IE_MASK 0x00000008UL

	/* MDIO Address Register Bit Masks */
	#define XEL_MDIOADDR_REGADR_MASK 0x0000001F /* Register Address */
	#define XEL_MDIOADDR_PHYADR_MASK 0x000003E0 /* PHY Address */
	#define XEL_MDIOADDR_PHYADR_SHIFT 5
	#define XEL_MDIOADDR_OP_MASK 0x00000400 /* RD/WR Operation */

	/* MDIO Write Data Register Bit Masks */
	#define XEL_MDIOWR_WRDATA_MASK 0x0000FFFF /* Data to be Written */

	/* MDIO Read Data Register Bit Masks */
	#define XEL_MDIORD_RDDATA_MASK 0x0000FFFF /* Data to be Read */

	/* MDIO Control Register Bit Masks */
	#define XEL_MDIOCTRL_MDIOSTS_MASK 0x00000001 /* MDIO Status Mask */
	#define XEL_MDIOCTRL_MDIOEN_MASK 0x00000008 /* MDIO Enable */

	struct emaclite_regs {
	u32 tx_ping; /* 0x0 - TX Ping buffer */
	u32 reserved1[504];
	u32 mdioaddr; /* 0x7e4 - MDIO Address Register */
	u32 mdiowr; /* 0x7e8 - MDIO Write Data Register */
	u32 mdiord;/* 0x7ec - MDIO Read Data Register */
	u32 mdioctrl; /* 0x7f0 - MDIO Control Register */
	u32 tx_ping_tplr; /* 0x7f4 - Tx packet length */
	u32 global_interrupt; /* 0x7f8 - Global interrupt enable */
	u32 tx_ping_tsr; /* 0x7fc - Tx status */
	u32 tx_pong; /* 0x800 - TX Pong buffer */
	u32 reserved2[508];
	u32 tx_pong_tplr; /* 0xff4 - Tx packet length */
	u32 reserved3; /* 0xff8 */
	u32 tx_pong_tsr; /* 0xffc - Tx status */
	u32 rx_ping; /* 0x1000 - Receive Buffer */
	u32 reserved4[510];
	u32 rx_ping_rsr; /* 0x17fc - Rx status */
	u32 rx_pong; /* 0x1800 - Receive Buffer */
	u32 reserved5[510];
	u32 rx_pong_rsr; /* 0x1ffc - Rx status */
	};

	struct xemaclite {
	bool use_rx_pong_buffer_next; /* Next RX buffer to read from */
	u32 txpp; /* TX ping pong buffer */
	u32 rxpp; /* RX ping pong buffer */
	int phyaddr;
	struct emaclite_regs *regs;
	struct phy_device *phydev;
	struct mii_dev *bus;
	};

	static uchar etherrxbuff[PKTSIZE_ALIGN]; /* Receive buffer */

	static void xemaclite_alignedread(u32 srcptr, void destptr, u32 bytecount)
	{
	u32 i;
	u32 alignbuffer;
	u32 *to32ptr;
	u32 *from32ptr;
	u8 *to8ptr;
	u8 *from8ptr;

	from32ptr = (u32 *) srcptr;

	/* Word aligned buffer, no correction needed. */
	to32ptr = (u32 *) destptr;
	while (bytecount > 3) {
	to32ptr++ = from32ptr++;
	bytecount -= 4;
	}
	to8ptr = (u8 *) to32ptr;

	alignbuffer = *from32ptr++;
	from8ptr = (u8 *) &alignbuffer;

	for (i = 0; i < bytecount; i++)
	to8ptr++ = from8ptr++;
	}

	static void xemaclite_alignedwrite(void srcptr, u32 destptr, u32 bytecount)
	{
	u32 i;
	u32 alignbuffer;
	u32 to32ptr = (u32 ) destptr;
	u32 *from32ptr;
	u8 *to8ptr;
	u8 *from8ptr;

	from32ptr = (u32 *) srcptr;
	while (bytecount > 3) {

	to32ptr++ = from32ptr++;
	bytecount -= 4;
	}

	alignbuffer = 0;
	to8ptr = (u8 *) &alignbuffer;
	from8ptr = (u8 *) from32ptr;

	for (i = 0; i < bytecount; i++)
	to8ptr++ = from8ptr++;

	*to32ptr++ = alignbuffer;
	}

	static int wait_for_bit(const char func, u32 reg, const u32 mask,
	bool set, unsigned int timeout)
	{
	u32 val;
	unsigned long start = get_timer(0);

	while (1) {
	val = __raw_readl(reg);

	if (!set)
	val = ~val;

	if ((val & mask) == mask)
	return 0;

	if (get_timer(start) > timeout)
	break;

	if (ctrlc()) {
	puts("Abort\n");
	return -EINTR;
	}

	udelay(1);
	}

	debug("%s: Timeout (reg=%p mask=%08x wait_set=%i)\n",
	func, reg, mask, set);

	return -ETIMEDOUT;
	}

	static int mdio_wait(struct emaclite_regs *regs)
	{
	return wait_for_bit(__func__, &regs->mdioctrl,
	XEL_MDIOCTRL_MDIOSTS_MASK, false, 2000);
	}

	static u32 phyread(struct xemaclite *emaclite, u32 phyaddress, u32 registernum,
	u16 *data)
	{
	struct emaclite_regs *regs = emaclite->regs;

	if (mdio_wait(regs))
	return 1;

	u32 ctrl_reg = __raw_readl(&regs->mdioctrl);
	__raw_writel(XEL_MDIOADDR_OP_MASK
	\| ((phyaddress << XEL_MDIOADDR_PHYADR_SHIFT)
	\| registernum), &regs->mdioaddr);
	__raw_writel(ctrl_reg \| XEL_MDIOCTRL_MDIOSTS_MASK, &regs->mdioctrl);

	if (mdio_wait(regs))
	return 1;

	/* Read data */
	*data = __raw_readl(&regs->mdiord);
	return 0;
	}

	static u32 phywrite(struct xemaclite *emaclite, u32 phyaddress, u32 registernum,
	u16 data)
	{
	struct emaclite_regs *regs = emaclite->regs;

	if (mdio_wait(regs))
	return 1;

	/*
	* Write the PHY address, register number and clear the OP bit in the
	* MDIO Address register and then write the value into the MDIO Write
	* Data register. Finally, set the Status bit in the MDIO Control
	* register to start a MDIO write transaction.
	*/
	u32 ctrl_reg = __raw_readl(&regs->mdioctrl);
	__raw_writel(~XEL_MDIOADDR_OP_MASK
	& ((phyaddress << XEL_MDIOADDR_PHYADR_SHIFT)
	\| registernum), &regs->mdioaddr);
	__raw_writel(data, &regs->mdiowr);
	__raw_writel(ctrl_reg \| XEL_MDIOCTRL_MDIOSTS_MASK, &regs->mdioctrl);

	if (mdio_wait(regs))
	return 1;

	return 0;
	}

	static void emaclite_stop(struct udevice *dev)
	{
	debug("eth_stop\n");
	}

	/* Use MII register 1 (MII status register) to detect PHY */
	#define PHY_DETECT_REG 1

	/* Mask used to verify certain PHY features (or register contents)
	* in the register above:
	* 0x1000: 10Mbps full duplex support
	* 0x0800: 10Mbps half duplex support
	* 0x0008: Auto-negotiation support
	*/
	#define PHY_DETECT_MASK 0x1808

	static int setup_phy(struct udevice *dev)
	{
	int i, ret;
	u16 phyreg;
	struct xemaclite *emaclite = dev_get_priv(dev);
	struct phy_device *phydev;

	u32 supported = SUPPORTED_10baseT_Half \|
	SUPPORTED_10baseT_Full \|
	SUPPORTED_100baseT_Half \|
	SUPPORTED_100baseT_Full;

	if (emaclite->phyaddr != -1) {
	phyread(emaclite, emaclite->phyaddr, PHY_DETECT_REG, &phyreg);
	if ((phyreg != 0xFFFF) &&
	((phyreg & PHY_DETECT_MASK) == PHY_DETECT_MASK)) {
	/* Found a valid PHY address */
	debug("Default phy address %d is valid\n",
	emaclite->phyaddr);
	} else {
	debug("PHY address is not setup correctly %d\n",
	emaclite->phyaddr);
	emaclite->phyaddr = -1;
	}
	}

	if (emaclite->phyaddr == -1) {
	/* detect the PHY address */
	for (i = 31; i >= 0; i--) {
	phyread(emaclite, i, PHY_DETECT_REG, &phyreg);
	if ((phyreg != 0xFFFF) &&
	((phyreg & PHY_DETECT_MASK) == PHY_DETECT_MASK)) {
	/* Found a valid PHY address */
	emaclite->phyaddr = i;
	debug("emaclite: Found valid phy address, %d\n",
	i);
	break;
	}
	}
	}

	/* interface - look at tsec */
	phydev = phy_connect(emaclite->bus, emaclite->phyaddr, dev,
	PHY_INTERFACE_MODE_MII);
	/*
	* Phy can support 1000baseT but device NOT that's why phydev->supported
	* must be setup for 1000baseT. phydev->advertising setups what speeds
	* will be used for autonegotiation where 1000baseT must be disabled.
	*/
	phydev->supported = supported \| SUPPORTED_1000baseT_Half \|
	SUPPORTED_1000baseT_Full;
	phydev->advertising = supported;
	emaclite->phydev = phydev;
	phy_config(phydev);
	ret = phy_startup(phydev);
	if (ret)
	return ret;

	if (!phydev->link) {
	printf("%s: No link.\n", phydev->dev->name);
	return 0;
	}

	/* Do not setup anything */
	return 1;
	}

	static int emaclite_start(struct udevice *dev)
	{
	struct xemaclite *emaclite = dev_get_priv(dev);
	struct eth_pdata *pdata = dev_get_platdata(dev);
	struct emaclite_regs *regs = emaclite->regs;

	debug("EmacLite Initialization Started\n");

	/*
	* TX - TX_PING & TX_PONG initialization
	*/
	/* Restart PING TX */
	__raw_writel(0, &regs->tx_ping_tsr);
	/* Copy MAC address */
	xemaclite_alignedwrite(pdata->enetaddr, &regs->tx_ping,
	ENET_ADDR_LENGTH);
	/* Set the length */
	__raw_writel(ENET_ADDR_LENGTH, &regs->tx_ping_tplr);
	/* Update the MAC address in the EMAC Lite */
	__raw_writel(XEL_TSR_PROG_MAC_ADDR, &regs->tx_ping_tsr);
	/* Wait for EMAC Lite to finish with the MAC address update */
	while ((__raw_readl(&regs->tx_ping_tsr) &
	XEL_TSR_PROG_MAC_ADDR) != 0)
	;

	if (emaclite->txpp) {
	/* The same operation with PONG TX */
	__raw_writel(0, &regs->tx_pong_tsr);
	xemaclite_alignedwrite(pdata->enetaddr, &regs->tx_pong,
	ENET_ADDR_LENGTH);
	__raw_writel(ENET_ADDR_LENGTH, &regs->tx_pong_tplr);
	__raw_writel(XEL_TSR_PROG_MAC_ADDR, &regs->tx_pong_tsr);
	while ((__raw_readl(&regs->tx_pong_tsr) &
	XEL_TSR_PROG_MAC_ADDR) != 0)
	;
	}

	/*
	* RX - RX_PING & RX_PONG initialization
	*/
	/* Write out the value to flush the RX buffer */
	__raw_writel(XEL_RSR_RECV_IE_MASK, &regs->rx_ping_rsr);

	if (emaclite->rxpp)
	__raw_writel(XEL_RSR_RECV_IE_MASK, &regs->rx_pong_rsr);

	__raw_writel(XEL_MDIOCTRL_MDIOEN_MASK, &regs->mdioctrl);
	if (__raw_readl(&regs->mdioctrl) & XEL_MDIOCTRL_MDIOEN_MASK)
	if (!setup_phy(dev))
	return -1;

	debug("EmacLite Initialization complete\n");
	return 0;
	}

	static int xemaclite_txbufferavailable(struct xemaclite *emaclite)
	{
	u32 tmp;
	struct emaclite_regs *regs = emaclite->regs;

	/*
	* Read the other buffer register
	* and determine if the other buffer is available
	*/
	tmp = ~__raw_readl(&regs->tx_ping_tsr);
	if (emaclite->txpp)
	tmp \|= ~__raw_readl(&regs->tx_pong_tsr);

	return !(tmp & XEL_TSR_XMIT_BUSY_MASK);
	}

	static int emaclite_send(struct udevice dev, void ptr, int len)
	{
	u32 reg;
	struct xemaclite *emaclite = dev_get_priv(dev);
	struct emaclite_regs *regs = emaclite->regs;

	u32 maxtry = 1000;

	if (len > PKTSIZE)
	len = PKTSIZE;

	while (xemaclite_txbufferavailable(emaclite) && maxtry) {
	udelay(10);
	maxtry--;
	}

	if (!maxtry) {
	printf("Error: Timeout waiting for ethernet TX buffer\n");
	/* Restart PING TX */
	__raw_writel(0, &regs->tx_ping_tsr);
	if (emaclite->txpp) {
	__raw_writel(0, &regs->tx_pong_tsr);
	}
	return -1;
	}

	/* Determine if the expected buffer address is empty */
	reg = __raw_readl(&regs->tx_ping_tsr);
	if ((reg & XEL_TSR_XMIT_BUSY_MASK) == 0) {
	debug("Send packet from tx_ping buffer\n");
	/* Write the frame to the buffer */
	xemaclite_alignedwrite(ptr, &regs->tx_ping, len);
	__raw_writel(len
	& (XEL_TPLR_LENGTH_MASK_HI \| XEL_TPLR_LENGTH_MASK_LO),
	&regs->tx_ping_tplr);
	reg = __raw_readl(&regs->tx_ping_tsr);
	reg \|= XEL_TSR_XMIT_BUSY_MASK;
	__raw_writel(reg, &regs->tx_ping_tsr);
	return 0;
	}

	if (emaclite->txpp) {
	/* Determine if the expected buffer address is empty */
	reg = __raw_readl(&regs->tx_pong_tsr);
	if ((reg & XEL_TSR_XMIT_BUSY_MASK) == 0) {
	debug("Send packet from tx_pong buffer\n");
	/* Write the frame to the buffer */
	xemaclite_alignedwrite(ptr, &regs->tx_pong, len);
	__raw_writel(len &
	(XEL_TPLR_LENGTH_MASK_HI \|
	XEL_TPLR_LENGTH_MASK_LO),
	&regs->tx_pong_tplr);
	reg = __raw_readl(&regs->tx_pong_tsr);
	reg \|= XEL_TSR_XMIT_BUSY_MASK;
	__raw_writel(reg, &regs->tx_pong_tsr);
	return 0;
	}
	}

	puts("Error while sending frame\n");
	return -1;
	}

	static int emaclite_recv(struct udevice dev, int flags, uchar *packetp)
	{
	u32 length, first_read, reg, attempt = 0;
	void addr, ack;
	struct xemaclite *emaclite = dev->priv;
	struct emaclite_regs *regs = emaclite->regs;
	struct ethernet_hdr *eth;
	struct ip_udp_hdr *ip;

	try_again:
	if (!emaclite->use_rx_pong_buffer_next) {
	reg = __raw_readl(&regs->rx_ping_rsr);
	debug("Testing data at rx_ping\n");
	if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
	debug("Data found in rx_ping buffer\n");
	addr = &regs->rx_ping;
	ack = &regs->rx_ping_rsr;
	} else {
	debug("Data not found in rx_ping buffer\n");
	/* Pong buffer is not available - return immediately */
	if (!emaclite->rxpp)
	return -1;

	/* Try pong buffer if this is first attempt */
	if (attempt++)
	return -1;
	emaclite->use_rx_pong_buffer_next =
	!emaclite->use_rx_pong_buffer_next;
	goto try_again;
	}
	} else {
	reg = __raw_readl(&regs->rx_pong_rsr);
	debug("Testing data at rx_pong\n");
	if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
	debug("Data found in rx_pong buffer\n");
	addr = &regs->rx_pong;
	ack = &regs->rx_pong_rsr;
	} else {
	debug("Data not found in rx_pong buffer\n");
	/* Try ping buffer if this is first attempt */
	if (attempt++)
	return -1;
	emaclite->use_rx_pong_buffer_next =
	!emaclite->use_rx_pong_buffer_next;
	goto try_again;
	}
	}

	/* Read all bytes for ARP packet with 32bit alignment - 48bytes */
	first_read = ALIGN(ETHER_HDR_SIZE + ARP_HDR_SIZE + ETH_FCS_LEN, 4);
	xemaclite_alignedread(addr, etherrxbuff, first_read);

	/* Detect real packet size */
	eth = (struct ethernet_hdr *)etherrxbuff;
	switch (ntohs(eth->et_protlen)) {
	case PROT_ARP:
	length = first_read;
	debug("ARP Packet %x\n", length);
	break;
	case PROT_IP:
	ip = (struct ip_udp_hdr *)(etherrxbuff + ETHER_HDR_SIZE);
	length = ntohs(ip->ip_len);
	length += ETHER_HDR_SIZE + ETH_FCS_LEN;
	debug("IP Packet %x\n", length);
	break;
	default:
	debug("Other Packet\n");
	length = PKTSIZE;
	break;
	}

	/* Read the rest of the packet which is longer then first read */
	if (length != first_read)
	xemaclite_alignedread(addr + first_read,
	etherrxbuff + first_read,
	length - first_read);

	/* Acknowledge the frame */
	reg = __raw_readl(ack);
	reg &= ~XEL_RSR_RECV_DONE_MASK;
	__raw_writel(reg, ack);

	debug("Packet receive from 0x%p, length %dB\n", addr, length);
	*packetp = etherrxbuff;
	return length;
	}

	static int emaclite_miiphy_read(struct mii_dev *bus, int addr,
	int devad, int reg)
	{
	u32 ret;
	u16 val = 0;

	ret = phyread(bus->priv, addr, reg, &val);
	debug("emaclite: Read MII 0x%x, 0x%x, 0x%x, %d\n", addr, reg, val, ret);
	return val;
	}

	static int emaclite_miiphy_write(struct mii_dev *bus, int addr, int devad,
	int reg, u16 value)
	{
	debug("emaclite: Write MII 0x%x, 0x%x, 0x%x\n", addr, reg, value);
	return phywrite(bus->priv, addr, reg, value);
	}

	static int emaclite_probe(struct udevice *dev)
	{
	struct xemaclite *emaclite = dev_get_priv(dev);
	int ret;

	emaclite->bus = mdio_alloc();
	emaclite->bus->read = emaclite_miiphy_read;
	emaclite->bus->write = emaclite_miiphy_write;
	emaclite->bus->priv = emaclite;

	ret = mdio_register_seq(emaclite->bus, dev->seq);
	if (ret)
	return ret;

	return 0;
	}

	static int emaclite_remove(struct udevice *dev)
	{
	struct xemaclite *emaclite = dev_get_priv(dev);

	free(emaclite->phydev);
	mdio_unregister(emaclite->bus);
	mdio_free(emaclite->bus);

	return 0;
	}

	static const struct eth_ops emaclite_ops = {
	.start = emaclite_start,
	.send = emaclite_send,
	.recv = emaclite_recv,
	.stop = emaclite_stop,
	};

	static int emaclite_ofdata_to_platdata(struct udevice *dev)
	{
	struct eth_pdata *pdata = dev_get_platdata(dev);
	struct xemaclite *emaclite = dev_get_priv(dev);
	int offset = 0;

	pdata->iobase = (phys_addr_t)dev_get_addr(dev);
	emaclite->regs = (struct emaclite_regs *)ioremap_nocache(pdata->iobase,
	0x10000);

	emaclite->phyaddr = -1;

	offset = fdtdec_lookup_phandle(gd->fdt_blob, dev_of_offset(dev),
	"phy-handle");
	if (offset > 0)
	emaclite->phyaddr = fdtdec_get_int(gd->fdt_blob, offset,
	"reg", -1);

	emaclite->txpp = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
	"xlnx,tx-ping-pong", 0);
	emaclite->rxpp = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
	"xlnx,rx-ping-pong", 0);

	printf("EMACLITE: %lx, phyaddr %d, %d/%d\n", (ulong)emaclite->regs,
	emaclite->phyaddr, emaclite->txpp, emaclite->rxpp);

	return 0;
	}

	static const struct udevice_id emaclite_ids[] = {
	{ .compatible = "xlnx,xps-ethernetlite-1.00.a" },
	{ }
	};

	U_BOOT_DRIVER(emaclite) = {
	.name = "emaclite",
	.id = UCLASS_ETH,
	.of_match = emaclite_ids,
	.ofdata_to_platdata = emaclite_ofdata_to_platdata,
	.probe = emaclite_probe,
	.remove = emaclite_remove,
	.ops = &emaclite_ops,
	.priv_auto_alloc_size = sizeof(struct xemaclite),
	.platdata_auto_alloc_size = sizeof(struct eth_pdata),
	};