drivers/net/xilinx_emaclite.c - github/trini/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 <malloc.h>
 #include <asm/io.h>
 #include <fdtdec.h>

 #undef DEBUG

 #define ENET_ADDR_LENGTH	6

 /* EmacLite constants */
 #define XEL_BUFFER_OFFSET	0x0800	/* Next buffer's offset */
 #define XEL_TPLR_OFFSET		0x07F4	/* Tx packet length */
 #define XEL_TSR_OFFSET		0x07FC	/* Tx status */
 #define XEL_RSR_OFFSET		0x17FC	/* Rx status */
 #define XEL_RXBUFF_OFFSET	0x1000	/* Receive Buffer */

 /* Xmit complete */
 #define XEL_TSR_XMIT_BUSY_MASK		0x00000001UL
 /* Xmit interrupt enable bit */
 #define XEL_TSR_XMIT_IE_MASK		0x00000008UL
 /* Buffer is active, SW bit only */
 #define XEL_TSR_XMIT_ACTIVE_MASK	0x80000000UL
 /* 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

 struct xemaclite {
 	u32 nexttxbuffertouse;	/* Next TX buffer to write to */
 	u32 nextrxbuffertouse;	/* Next RX buffer to read from */
 	u32 txpp;		/* TX ping pong buffer */
 	u32 rxpp;		/* RX ping pong buffer */
 };

 static u32 etherrxbuff[PKTSIZE_ALIGN/4]; /* 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 void emaclite_halt(struct eth_device *dev)
 {
 	debug("eth_halt\n");
 }

 static int emaclite_init(struct eth_device *dev, bd_t *bis)
 {
 	struct xemaclite *emaclite = dev->priv;
 	debug("EmacLite Initialization Started\n");

 /*
  * TX - TX_PING & TX_PONG initialization
  */
 	/* Restart PING TX */
 	out_be32 (dev->iobase + XEL_TSR_OFFSET, 0);
 	/* Copy MAC address */
 	xemaclite_alignedwrite(dev->enetaddr, dev->iobase, ENET_ADDR_LENGTH);
 	/* Set the length */
 	out_be32 (dev->iobase + XEL_TPLR_OFFSET, ENET_ADDR_LENGTH);
 	/* Update the MAC address in the EMAC Lite */
 	out_be32 (dev->iobase + XEL_TSR_OFFSET, XEL_TSR_PROG_MAC_ADDR);
 	/* Wait for EMAC Lite to finish with the MAC address update */
 	while ((in_be32 (dev->iobase + XEL_TSR_OFFSET) &
 		XEL_TSR_PROG_MAC_ADDR) != 0)
 		;

 	if (emaclite->txpp) {
 		/* The same operation with PONG TX */
 		out_be32 (dev->iobase + XEL_TSR_OFFSET + XEL_BUFFER_OFFSET, 0);
 		xemaclite_alignedwrite(dev->enetaddr, dev->iobase +
 			XEL_BUFFER_OFFSET, ENET_ADDR_LENGTH);
 		out_be32 (dev->iobase + XEL_TPLR_OFFSET, ENET_ADDR_LENGTH);
 		out_be32 (dev->iobase + XEL_TSR_OFFSET + XEL_BUFFER_OFFSET,
 			XEL_TSR_PROG_MAC_ADDR);
 		while ((in_be32 (dev->iobase + XEL_TSR_OFFSET +
 			XEL_BUFFER_OFFSET) & XEL_TSR_PROG_MAC_ADDR) != 0)
 			;
 	}

 /*
  * RX - RX_PING & RX_PONG initialization
  */
 	/* Write out the value to flush the RX buffer */
 	out_be32 (dev->iobase + XEL_RSR_OFFSET, XEL_RSR_RECV_IE_MASK);

 	if (emaclite->rxpp)
 		out_be32 (dev->iobase + XEL_RSR_OFFSET + XEL_BUFFER_OFFSET,
 			XEL_RSR_RECV_IE_MASK);

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

 static int xemaclite_txbufferavailable(struct eth_device *dev)
 {
 	u32 reg;
 	u32 txpingbusy;
 	u32 txpongbusy;
 	struct xemaclite *emaclite = dev->priv;

 	/*
 	 * Read the other buffer register
 	 * and determine if the other buffer is available
 	 */
 	reg = in_be32 (dev->iobase +
 			emaclite->nexttxbuffertouse + 0);
 	txpingbusy = ((reg & XEL_TSR_XMIT_BUSY_MASK) ==
 			XEL_TSR_XMIT_BUSY_MASK);

 	reg = in_be32 (dev->iobase +
 			(emaclite->nexttxbuffertouse ^ XEL_TSR_OFFSET) + 0);
 	txpongbusy = ((reg & XEL_TSR_XMIT_BUSY_MASK) ==
 			XEL_TSR_XMIT_BUSY_MASK);

 	return !(txpingbusy && txpongbusy);
 }

 static int emaclite_send(struct eth_device *dev, void *ptr, int len)
 {
 	u32 reg;
 	u32 baseaddress;
 	struct xemaclite *emaclite = dev->priv;

 	u32 maxtry = 1000;

 	if (len > PKTSIZE)
 		len = PKTSIZE;

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

 	if (!maxtry) {
 		printf("Error: Timeout waiting for ethernet TX buffer\n");
 		/* Restart PING TX */
 		out_be32 (dev->iobase + XEL_TSR_OFFSET, 0);
 		if (emaclite->txpp) {
 			out_be32 (dev->iobase + XEL_TSR_OFFSET +
 				XEL_BUFFER_OFFSET, 0);
 		}
 		return -1;
 	}

 	/* Determine the expected TX buffer address */
 	baseaddress = (dev->iobase + emaclite->nexttxbuffertouse);

 	/* Determine if the expected buffer address is empty */
 	reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
 	if (((reg & XEL_TSR_XMIT_BUSY_MASK) == 0)
 		&& ((in_be32 ((baseaddress) + XEL_TSR_OFFSET)
 			& XEL_TSR_XMIT_ACTIVE_MASK) == 0)) {

 		if (emaclite->txpp)
 			emaclite->nexttxbuffertouse ^= XEL_BUFFER_OFFSET;

 		debug("Send packet from 0x%x\n", baseaddress);
 		/* Write the frame to the buffer */
 		xemaclite_alignedwrite(ptr, baseaddress, len);
 		out_be32 (baseaddress + XEL_TPLR_OFFSET,(len &
 			(XEL_TPLR_LENGTH_MASK_HI | XEL_TPLR_LENGTH_MASK_LO)));
 		reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
 		reg |= XEL_TSR_XMIT_BUSY_MASK;
 		if ((reg & XEL_TSR_XMIT_IE_MASK) != 0)
 			reg |= XEL_TSR_XMIT_ACTIVE_MASK;
 		out_be32 (baseaddress + XEL_TSR_OFFSET, reg);
 		return 0;
 	}

 	if (emaclite->txpp) {
 		/* Switch to second buffer */
 		baseaddress ^= XEL_BUFFER_OFFSET;
 		/* Determine if the expected buffer address is empty */
 		reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
 		if (((reg & XEL_TSR_XMIT_BUSY_MASK) == 0)
 			&& ((in_be32 ((baseaddress) + XEL_TSR_OFFSET)
 				& XEL_TSR_XMIT_ACTIVE_MASK) == 0)) {
 			debug("Send packet from 0x%x\n", baseaddress);
 			/* Write the frame to the buffer */
 			xemaclite_alignedwrite(ptr, baseaddress, len);
 			out_be32 (baseaddress + XEL_TPLR_OFFSET, (len &
 				(XEL_TPLR_LENGTH_MASK_HI |
 					XEL_TPLR_LENGTH_MASK_LO)));
 			reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
 			reg |= XEL_TSR_XMIT_BUSY_MASK;
 			if ((reg & XEL_TSR_XMIT_IE_MASK) != 0)
 				reg |= XEL_TSR_XMIT_ACTIVE_MASK;
 			out_be32 (baseaddress + XEL_TSR_OFFSET, reg);
 			return 0;
 		}
 	}

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

 static int emaclite_recv(struct eth_device *dev)
 {
 	u32 length;
 	u32 reg;
 	u32 baseaddress;
 	struct xemaclite *emaclite = dev->priv;

 	baseaddress = dev->iobase + emaclite->nextrxbuffertouse;
 	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
 	debug("Testing data at address 0x%x\n", baseaddress);
 	if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
 		if (emaclite->rxpp)
 			emaclite->nextrxbuffertouse ^= XEL_BUFFER_OFFSET;
 	} else {

 		if (!emaclite->rxpp) {
 			debug("No data was available - address 0x%x\n",
 								baseaddress);
 			return 0;
 		} else {
 			baseaddress ^= XEL_BUFFER_OFFSET;
 			reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
 			if ((reg & XEL_RSR_RECV_DONE_MASK) !=
 						XEL_RSR_RECV_DONE_MASK) {
 				debug("No data was available - address 0x%x\n",
 						baseaddress);
 				return 0;
 			}
 		}
 	}
 	/* Get the length of the frame that arrived */
 	switch(((ntohl(in_be32 (baseaddress + XEL_RXBUFF_OFFSET + 0xC))) &
 			0xFFFF0000 ) >> 16) {
 		case 0x806:
 			length = 42 + 20; /* FIXME size of ARP */
 			debug("ARP Packet\n");
 			break;
 		case 0x800:
 			length = 14 + 14 +
 			(((ntohl(in_be32 (baseaddress + XEL_RXBUFF_OFFSET +
 						0x10))) & 0xFFFF0000) >> 16);
 			/* FIXME size of IP packet */
 			debug ("IP Packet\n");
 			break;
 		default:
 			debug("Other Packet\n");
 			length = PKTSIZE;
 			break;
 	}

 	xemaclite_alignedread((u32 *) (baseaddress + XEL_RXBUFF_OFFSET),
 			etherrxbuff, length);

 	/* Acknowledge the frame */
 	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
 	reg &= ~XEL_RSR_RECV_DONE_MASK;
 	out_be32 (baseaddress + XEL_RSR_OFFSET, reg);

 	debug("Packet receive from 0x%x, length %dB\n", baseaddress, length);
 	NetReceive((uchar *) etherrxbuff, length);
 	return length;

 }

 int xilinx_emaclite_initialize(bd_t *bis, unsigned long base_addr,
 							int txpp, int rxpp)
 {
 	struct eth_device *dev;
 	struct xemaclite *emaclite;

 	dev = calloc(1, sizeof(*dev));
 	if (dev == NULL)
 		return -1;

 	emaclite = calloc(1, sizeof(struct xemaclite));
 	if (emaclite == NULL) {
 		free(dev);
 		return -1;
 	}

 	dev->priv = emaclite;

 	emaclite->txpp = txpp;
 	emaclite->rxpp = rxpp;

 	sprintf(dev->name, "Xelite.%lx", base_addr);

 	dev->iobase = base_addr;
 	dev->init = emaclite_init;
 	dev->halt = emaclite_halt;
 	dev->send = emaclite_send;
 	dev->recv = emaclite_recv;

 	eth_register(dev);

 	return 1;
 }

 #ifdef CONFIG_OF_CONTROL
 int xilinx_emaclite_of_init(const void *blob)
 {
 	int offset = 0;
 	u32 ret = 0;
 	u32 reg;

 	do {
 		offset = fdt_node_offset_by_compatible(blob, offset,
 					"xlnx,xps-ethernetlite-1.00.a");
 		if (offset != -1) {
 			reg = fdtdec_get_addr(blob, offset, "reg");
 			if (reg != FDT_ADDR_T_NONE) {
 				u32 rxpp = fdtdec_get_int(blob, offset,
 							"xlnx,rx-ping-pong", 0);
 				u32 txpp = fdtdec_get_int(blob, offset,
 							"xlnx,tx-ping-pong", 0);
 				ret |= xilinx_emaclite_initialize(NULL, reg,
 								txpp, rxpp);
 			} else {
 				debug("EMACLITE: Can't get base address\n");
 				return -1;
 			}
 		}
 	} while (offset != -1);

 	return ret;
 }
 #endif
	/*
	* (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 <malloc.h>
	#include <asm/io.h>
	#include <fdtdec.h>

	#undef DEBUG

	#define ENET_ADDR_LENGTH 6

	/* EmacLite constants */
	#define XEL_BUFFER_OFFSET 0x0800 /* Next buffer's offset */
	#define XEL_TPLR_OFFSET 0x07F4 /* Tx packet length */
	#define XEL_TSR_OFFSET 0x07FC /* Tx status */
	#define XEL_RSR_OFFSET 0x17FC /* Rx status */
	#define XEL_RXBUFF_OFFSET 0x1000 /* Receive Buffer */

	/* Xmit complete */
	#define XEL_TSR_XMIT_BUSY_MASK 0x00000001UL
	/* Xmit interrupt enable bit */
	#define XEL_TSR_XMIT_IE_MASK 0x00000008UL
	/* Buffer is active, SW bit only */
	#define XEL_TSR_XMIT_ACTIVE_MASK 0x80000000UL
	/* 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

	struct xemaclite {
	u32 nexttxbuffertouse; /* Next TX buffer to write to */
	u32 nextrxbuffertouse; /* Next RX buffer to read from */
	u32 txpp; /* TX ping pong buffer */
	u32 rxpp; /* RX ping pong buffer */
	};

	static u32 etherrxbuff[PKTSIZE_ALIGN/4]; /* 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 void emaclite_halt(struct eth_device *dev)
	{
	debug("eth_halt\n");
	}

	static int emaclite_init(struct eth_device dev, bd_t bis)
	{
	struct xemaclite *emaclite = dev->priv;
	debug("EmacLite Initialization Started\n");

	/*
	* TX - TX_PING & TX_PONG initialization
	*/
	/* Restart PING TX */
	out_be32 (dev->iobase + XEL_TSR_OFFSET, 0);
	/* Copy MAC address */
	xemaclite_alignedwrite(dev->enetaddr, dev->iobase, ENET_ADDR_LENGTH);
	/* Set the length */
	out_be32 (dev->iobase + XEL_TPLR_OFFSET, ENET_ADDR_LENGTH);
	/* Update the MAC address in the EMAC Lite */
	out_be32 (dev->iobase + XEL_TSR_OFFSET, XEL_TSR_PROG_MAC_ADDR);
	/* Wait for EMAC Lite to finish with the MAC address update */
	while ((in_be32 (dev->iobase + XEL_TSR_OFFSET) &
	XEL_TSR_PROG_MAC_ADDR) != 0)
	;

	if (emaclite->txpp) {
	/* The same operation with PONG TX */
	out_be32 (dev->iobase + XEL_TSR_OFFSET + XEL_BUFFER_OFFSET, 0);
	xemaclite_alignedwrite(dev->enetaddr, dev->iobase +
	XEL_BUFFER_OFFSET, ENET_ADDR_LENGTH);
	out_be32 (dev->iobase + XEL_TPLR_OFFSET, ENET_ADDR_LENGTH);
	out_be32 (dev->iobase + XEL_TSR_OFFSET + XEL_BUFFER_OFFSET,
	XEL_TSR_PROG_MAC_ADDR);
	while ((in_be32 (dev->iobase + XEL_TSR_OFFSET +
	XEL_BUFFER_OFFSET) & XEL_TSR_PROG_MAC_ADDR) != 0)
	;
	}

	/*
	* RX - RX_PING & RX_PONG initialization
	*/
	/* Write out the value to flush the RX buffer */
	out_be32 (dev->iobase + XEL_RSR_OFFSET, XEL_RSR_RECV_IE_MASK);

	if (emaclite->rxpp)
	out_be32 (dev->iobase + XEL_RSR_OFFSET + XEL_BUFFER_OFFSET,
	XEL_RSR_RECV_IE_MASK);

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

	static int xemaclite_txbufferavailable(struct eth_device *dev)
	{
	u32 reg;
	u32 txpingbusy;
	u32 txpongbusy;
	struct xemaclite *emaclite = dev->priv;

	/*
	* Read the other buffer register
	* and determine if the other buffer is available
	*/
	reg = in_be32 (dev->iobase +
	emaclite->nexttxbuffertouse + 0);
	txpingbusy = ((reg & XEL_TSR_XMIT_BUSY_MASK) ==
	XEL_TSR_XMIT_BUSY_MASK);

	reg = in_be32 (dev->iobase +
	(emaclite->nexttxbuffertouse ^ XEL_TSR_OFFSET) + 0);
	txpongbusy = ((reg & XEL_TSR_XMIT_BUSY_MASK) ==
	XEL_TSR_XMIT_BUSY_MASK);

	return !(txpingbusy && txpongbusy);
	}

	static int emaclite_send(struct eth_device dev, void ptr, int len)
	{
	u32 reg;
	u32 baseaddress;
	struct xemaclite *emaclite = dev->priv;

	u32 maxtry = 1000;

	if (len > PKTSIZE)
	len = PKTSIZE;

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

	if (!maxtry) {
	printf("Error: Timeout waiting for ethernet TX buffer\n");
	/* Restart PING TX */
	out_be32 (dev->iobase + XEL_TSR_OFFSET, 0);
	if (emaclite->txpp) {
	out_be32 (dev->iobase + XEL_TSR_OFFSET +
	XEL_BUFFER_OFFSET, 0);
	}
	return -1;
	}

	/* Determine the expected TX buffer address */
	baseaddress = (dev->iobase + emaclite->nexttxbuffertouse);

	/* Determine if the expected buffer address is empty */
	reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
	if (((reg & XEL_TSR_XMIT_BUSY_MASK) == 0)
	&& ((in_be32 ((baseaddress) + XEL_TSR_OFFSET)
	& XEL_TSR_XMIT_ACTIVE_MASK) == 0)) {

	if (emaclite->txpp)
	emaclite->nexttxbuffertouse ^= XEL_BUFFER_OFFSET;

	debug("Send packet from 0x%x\n", baseaddress);
	/* Write the frame to the buffer */
	xemaclite_alignedwrite(ptr, baseaddress, len);
	out_be32 (baseaddress + XEL_TPLR_OFFSET,(len &
	(XEL_TPLR_LENGTH_MASK_HI \| XEL_TPLR_LENGTH_MASK_LO)));
	reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
	reg \|= XEL_TSR_XMIT_BUSY_MASK;
	if ((reg & XEL_TSR_XMIT_IE_MASK) != 0)
	reg \|= XEL_TSR_XMIT_ACTIVE_MASK;
	out_be32 (baseaddress + XEL_TSR_OFFSET, reg);
	return 0;
	}

	if (emaclite->txpp) {
	/* Switch to second buffer */
	baseaddress ^= XEL_BUFFER_OFFSET;
	/* Determine if the expected buffer address is empty */
	reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
	if (((reg & XEL_TSR_XMIT_BUSY_MASK) == 0)
	&& ((in_be32 ((baseaddress) + XEL_TSR_OFFSET)
	& XEL_TSR_XMIT_ACTIVE_MASK) == 0)) {
	debug("Send packet from 0x%x\n", baseaddress);
	/* Write the frame to the buffer */
	xemaclite_alignedwrite(ptr, baseaddress, len);
	out_be32 (baseaddress + XEL_TPLR_OFFSET, (len &
	(XEL_TPLR_LENGTH_MASK_HI \|
	XEL_TPLR_LENGTH_MASK_LO)));
	reg = in_be32 (baseaddress + XEL_TSR_OFFSET);
	reg \|= XEL_TSR_XMIT_BUSY_MASK;
	if ((reg & XEL_TSR_XMIT_IE_MASK) != 0)
	reg \|= XEL_TSR_XMIT_ACTIVE_MASK;
	out_be32 (baseaddress + XEL_TSR_OFFSET, reg);
	return 0;
	}
	}

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

	static int emaclite_recv(struct eth_device *dev)
	{
	u32 length;
	u32 reg;
	u32 baseaddress;
	struct xemaclite *emaclite = dev->priv;

	baseaddress = dev->iobase + emaclite->nextrxbuffertouse;
	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
	debug("Testing data at address 0x%x\n", baseaddress);
	if ((reg & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
	if (emaclite->rxpp)
	emaclite->nextrxbuffertouse ^= XEL_BUFFER_OFFSET;
	} else {

	if (!emaclite->rxpp) {
	debug("No data was available - address 0x%x\n",
	baseaddress);
	return 0;
	} else {
	baseaddress ^= XEL_BUFFER_OFFSET;
	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
	if ((reg & XEL_RSR_RECV_DONE_MASK) !=
	XEL_RSR_RECV_DONE_MASK) {
	debug("No data was available - address 0x%x\n",
	baseaddress);
	return 0;
	}
	}
	}
	/* Get the length of the frame that arrived */
	switch(((ntohl(in_be32 (baseaddress + XEL_RXBUFF_OFFSET + 0xC))) &
	0xFFFF0000 ) >> 16) {
	case 0x806:
	length = 42 + 20; /* FIXME size of ARP */
	debug("ARP Packet\n");
	break;
	case 0x800:
	length = 14 + 14 +
	(((ntohl(in_be32 (baseaddress + XEL_RXBUFF_OFFSET +
	0x10))) & 0xFFFF0000) >> 16);
	/* FIXME size of IP packet */
	debug ("IP Packet\n");
	break;
	default:
	debug("Other Packet\n");
	length = PKTSIZE;
	break;
	}

	xemaclite_alignedread((u32 *) (baseaddress + XEL_RXBUFF_OFFSET),
	etherrxbuff, length);

	/* Acknowledge the frame */
	reg = in_be32 (baseaddress + XEL_RSR_OFFSET);
	reg &= ~XEL_RSR_RECV_DONE_MASK;
	out_be32 (baseaddress + XEL_RSR_OFFSET, reg);

	debug("Packet receive from 0x%x, length %dB\n", baseaddress, length);
	NetReceive((uchar *) etherrxbuff, length);
	return length;

	}

	int xilinx_emaclite_initialize(bd_t *bis, unsigned long base_addr,
	int txpp, int rxpp)
	{
	struct eth_device *dev;
	struct xemaclite *emaclite;

	dev = calloc(1, sizeof(*dev));
	if (dev == NULL)
	return -1;

	emaclite = calloc(1, sizeof(struct xemaclite));
	if (emaclite == NULL) {
	free(dev);
	return -1;
	}

	dev->priv = emaclite;

	emaclite->txpp = txpp;
	emaclite->rxpp = rxpp;

	sprintf(dev->name, "Xelite.%lx", base_addr);

	dev->iobase = base_addr;
	dev->init = emaclite_init;
	dev->halt = emaclite_halt;
	dev->send = emaclite_send;
	dev->recv = emaclite_recv;

	eth_register(dev);

	return 1;
	}

	#ifdef CONFIG_OF_CONTROL
	int xilinx_emaclite_of_init(const void *blob)
	{
	int offset = 0;
	u32 ret = 0;
	u32 reg;

	do {
	offset = fdt_node_offset_by_compatible(blob, offset,
	"xlnx,xps-ethernetlite-1.00.a");
	if (offset != -1) {
	reg = fdtdec_get_addr(blob, offset, "reg");
	if (reg != FDT_ADDR_T_NONE) {
	u32 rxpp = fdtdec_get_int(blob, offset,
	"xlnx,rx-ping-pong", 0);
	u32 txpp = fdtdec_get_int(blob, offset,
	"xlnx,tx-ping-pong", 0);
	ret \|= xilinx_emaclite_initialize(NULL, reg,
	txpp, rxpp);
	} else {
	debug("EMACLITE: Can't get base address\n");
	return -1;
	}
	}
	} while (offset != -1);

	return ret;
	}
	#endif