drivers/pcnet.c - uboot/mindspeed - Git at Google

 /*
  * (C) Copyright 2002 Wolfgang Grandegger, wg@denx.de.
  *
  * This driver for AMD PCnet network controllers is derived from the
  * Linux driver pcnet32.c written 1996-1999 by Thomas Bogendoerfer.
  *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of
  * the License, or (at your option) any later version.
  *
  * 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, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  * MA 02111-1307 USA
  */

 #include <common.h>
 #include <malloc.h>
 #include <net.h>
 #include <asm/io.h>
 #include <pci.h>

 #if 0
 #define	PCNET_DEBUG_LEVEL	0 /* 0=off, 1=init, 2=rx/tx */
 #endif

 #if PCNET_DEBUG_LEVEL > 0
 #define	PCNET_DEBUG1(fmt,args...)	printf (fmt ,##args)
 #if PCNET_DEBUG_LEVEL > 1
 #define	PCNET_DEBUG2(fmt,args...)	printf (fmt ,##args)
 #else
 #define PCNET_DEBUG2(fmt,args...)
 #endif
 #else
 #define PCNET_DEBUG1(fmt,args...)
 #define PCNET_DEBUG2(fmt,args...)
 #endif

 #if (CONFIG_COMMANDS & CFG_CMD_NET) && defined(CONFIG_NET_MULTI) \
     && defined(CONFIG_PCNET)

 #if !defined(CONF_PCNET_79C973) && defined(CONF_PCNET_79C975)
 #error "Macro for PCnet chip version is not defined!"
 #endif

 /*
  * Set the number of Tx and Rx buffers, using Log_2(# buffers).
  * Reasonable default values are 4 Tx buffers, and 16 Rx buffers.
  * That translates to 2 (4 == 2^^2) and 4 (16 == 2^^4).
  */
 #define PCNET_LOG_TX_BUFFERS	0
 #define PCNET_LOG_RX_BUFFERS	2

 #define TX_RING_SIZE		(1 << (PCNET_LOG_TX_BUFFERS))
 #define TX_RING_LEN_BITS	((PCNET_LOG_TX_BUFFERS) << 12)

 #define RX_RING_SIZE		(1 << (PCNET_LOG_RX_BUFFERS))
 #define RX_RING_LEN_BITS	((PCNET_LOG_RX_BUFFERS) << 4)

 #define PKT_BUF_SZ		1544

 /* The PCNET Rx and Tx ring descriptors. */
 struct pcnet_rx_head {
     u32 base;
     s16 buf_length;
     s16 status;
     u32 msg_length;
     u32 reserved;
 };

 struct pcnet_tx_head {
     u32 base;
     s16 length;
     s16 status;
     u32 misc;
     u32 reserved;
 };

 /* The PCNET 32-Bit initialization block, described in databook. */
 struct pcnet_init_block {
     u16 mode;
     u16 tlen_rlen;
     u8	phys_addr[6];
     u16 reserved;
     u32 filter[2];
     /* Receive and transmit ring base, along with extra bits. */
     u32 rx_ring;
     u32 tx_ring;
     u32 reserved2;
 };

 typedef struct pcnet_priv {
     struct pcnet_rx_head    rx_ring[RX_RING_SIZE];
     struct pcnet_tx_head    tx_ring[TX_RING_SIZE];
     struct pcnet_init_block init_block;
     /* Receive Buffer space */
     unsigned char rx_buf[RX_RING_SIZE][PKT_BUF_SZ + 4];
     int cur_rx;
     int cur_tx;
 } pcnet_priv_t;

 static pcnet_priv_t *lp;

 /* Offsets from base I/O address for WIO mode */
 #define PCNET_RDP		0x10
 #define PCNET_RAP		0x12
 #define PCNET_RESET		0x14
 #define PCNET_BDP		0x16

 static u16 pcnet_read_csr (struct eth_device *dev, int index)
 {
     outw (index, dev->iobase+PCNET_RAP);
     return inw (dev->iobase+PCNET_RDP);
 }

 static void pcnet_write_csr (struct eth_device *dev, int index, u16 val)
 {
     outw (index, dev->iobase+PCNET_RAP);
     outw (val, dev->iobase+PCNET_RDP);
 }

 static u16 pcnet_read_bcr (struct eth_device *dev, int index)
 {
     outw (index, dev->iobase+PCNET_RAP);
     return inw (dev->iobase+PCNET_BDP);
 }

 static void pcnet_write_bcr (struct eth_device *dev, int index, u16 val)
 {
     outw (index, dev->iobase+PCNET_RAP);
     outw (val, dev->iobase+PCNET_BDP);
 }

 static void pcnet_reset (struct eth_device *dev)
 {
     inw (dev->iobase+PCNET_RESET);
 }

 static int pcnet_check (struct eth_device *dev)
 {
     outw (88, dev->iobase+PCNET_RAP);
     return (inw (dev->iobase+PCNET_RAP) == 88);
 }

 static int  pcnet_init( struct eth_device* dev, bd_t *bis);
 static int  pcnet_send (struct eth_device* dev, volatile void *packet,
 			int length);
 static int  pcnet_recv (struct eth_device* dev);
 static void pcnet_halt (struct eth_device* dev);
 static int  pcnet_probe(struct eth_device* dev, bd_t *bis, int dev_num);

 #define PCI_TO_MEM(d,a) pci_phys_to_mem((pci_dev_t)d->priv, (u_long)(a))
 #define PCI_TO_MEM_LE(d,a) (u32)(cpu_to_le32(PCI_TO_MEM(d,a)))

 static struct pci_device_id supported[] = {
 	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_LANCE },
 	{ }
 };


 int pcnet_initialize(bd_t *bis)
 {
     pci_dev_t devbusfn;
     struct eth_device* dev;
     u16 command, status;
     int dev_nr = 0;

     PCNET_DEBUG1("\npcnet_initialize...\n");

     for (dev_nr = 0; ; dev_nr++) {

 	/*
 	 * Find the PCnet PCI device(s).
 	 */
 	if ((devbusfn = pci_find_devices(supported, dev_nr)) < 0) {
 	    break;
 	}

 	/*
 	 * Allocate and pre-fill the device structure.
 	 */
 	dev = (struct eth_device*) malloc(sizeof *dev);
 	dev->priv = (void *)devbusfn;
 	sprintf(dev->name, "pcnet#%d", dev_nr);

 	/*
 	 * Setup the PCI device.
 	 */
 	pci_read_config_dword(devbusfn, PCI_BASE_ADDRESS_0, (unsigned int *)&dev->iobase);
 	dev->iobase &= ~0xf;

 	PCNET_DEBUG1("%s: devbusfn=0x%x iobase=0x%x: ",
 	       dev->name, devbusfn, dev->iobase);

 	command = PCI_COMMAND_IO | PCI_COMMAND_MASTER;
 	pci_write_config_word(devbusfn, PCI_COMMAND, command);
 	pci_read_config_word(devbusfn, PCI_COMMAND, &status);
 	if ((status & command) != command) {
 	    printf("%s: Couldn't enable IO access or Bus Mastering\n",
 		   dev->name);
 	    free(dev);
 	    continue;
 	}

 	pci_write_config_byte(devbusfn, PCI_LATENCY_TIMER, 0x40);

 	/*
 	 * Probe the PCnet chip.
 	 */
 	if (pcnet_probe(dev, bis, dev_nr) < 0) {
 	    free(dev);
 	    continue;
 	}

 	/*
 	 * Setup device structure and register the driver.
 	 */
 	dev->init   = pcnet_init;
 	dev->halt   = pcnet_halt;
 	dev->send   = pcnet_send;
 	dev->recv   = pcnet_recv;

 	eth_register(dev);
     }

     udelay(10 * 1000);

     return dev_nr;
 }

 static int pcnet_probe(struct eth_device* dev, bd_t *bis, int dev_nr)
 {
     int chip_version;
     char *chipname;
 #ifdef PCNET_HAS_PROM
     int i;
 #endif

     /* Reset the PCnet controller */
     pcnet_reset(dev);

     /* Check if register access is working */
     if (pcnet_read_csr(dev, 0) != 4 || !pcnet_check(dev)) {
 	printf("%s: CSR register access check failed\n", dev->name);
 	return -1;
     }

     /* Identify the chip */
     chip_version = pcnet_read_csr(dev, 88) | (pcnet_read_csr(dev,89) << 16);
     if ((chip_version & 0xfff) != 0x003)
        return -1;
     chip_version = (chip_version >> 12) & 0xffff;
     switch (chip_version) {
 #ifdef CONFIG_PCNET_79C973
     case 0x2625:
 	chipname = "PCnet/FAST III 79C973"; /* PCI */
 	break;
 #endif
 #ifdef CONFIG_PCNET_79C975
     case 0x2627:
 	chipname = "PCnet/FAST III 79C975"; /* PCI */
 	break;
 #endif
     default:
 	printf("%s: PCnet version %#x not supported\n",
 	       dev->name, chip_version);
 	return -1;
     }

     PCNET_DEBUG1("AMD %s\n", chipname);

 #ifdef PCNET_HAS_PROM
     /*
      * In most chips, after a chip reset, the ethernet address is read from
      * the station address PROM at the base address and programmed into the
      * "Physical Address Registers" CSR12-14.
      */
     for (i = 0; i < 3; i++) {
 	unsigned int val;
 	val = pcnet_read_csr(dev, i+12) & 0x0ffff;
 	/* There may be endianness issues here. */
 	dev->enetaddr[2*i  ] =  val       & 0x0ff;
 	dev->enetaddr[2*i+1] = (val >> 8) & 0x0ff;
     }
 #endif /* PCNET_HAS_PROM */

     return 0;
 }

 static int pcnet_init(struct eth_device* dev, bd_t *bis)
 {
     int i, val;
     u32 addr;

     PCNET_DEBUG1("%s: pcnet_init...\n", dev->name);

     /* Switch pcnet to 32bit mode */
     pcnet_write_bcr (dev, 20, 2);

 #ifdef CONFIG_PN62
     /* Setup LED registers */
     val = pcnet_read_bcr (dev, 2) | 0x1000;
     pcnet_write_bcr (dev, 2, val);    /* enable LEDPE */
     pcnet_write_bcr (dev, 4, 0x5080); /* 100MBit */
     pcnet_write_bcr (dev, 5, 0x40c0); /* LNKSE */
     pcnet_write_bcr (dev, 6, 0x4090); /* TX Activity */
     pcnet_write_bcr (dev, 7, 0x4084); /* RX Activity */
 #endif

     /* Set/reset autoselect bit */
     val = pcnet_read_bcr (dev, 2) & ~2;
     val |= 2;
     pcnet_write_bcr (dev, 2, val);

     /* Enable auto negotiate, setup, disable fd */
     val = pcnet_read_bcr(dev, 32) & ~0x98;
     val |= 0x20;
     pcnet_write_bcr(dev, 32, val);

     /*
      * We only maintain one structure because the drivers will never
      * be used concurrently. In 32bit mode the RX and TX ring entries
      * must be aligned on 16-byte boundaries.
      */
     if (lp == NULL) {
 	addr = (u32)malloc(sizeof(pcnet_priv_t) + 0x10);
 	addr = (addr + 0xf) & ~0xf;
 	lp = (pcnet_priv_t *)addr;
     }

     lp->init_block.mode = cpu_to_le16(0x0000);
     lp->init_block.filter[0] = 0x00000000;
     lp->init_block.filter[1] = 0x00000000;

     /*
      * Initialize the Rx ring.
      */
     lp->cur_rx = 0;
     for (i = 0; i < RX_RING_SIZE; i++) {
 	lp->rx_ring[i].base = PCI_TO_MEM_LE(dev, lp->rx_buf[i]);
 	lp->rx_ring[i].buf_length = cpu_to_le16(-PKT_BUF_SZ);
 	lp->rx_ring[i].status = cpu_to_le16(0x8000);
 	PCNET_DEBUG1("Rx%d: base=0x%x buf_length=0x%hx status=0x%hx\n",
 	       i, lp->rx_ring[i].base, lp->rx_ring[i].buf_length,
 	       lp->rx_ring[i].status);
     }

     /*
      * Initialize the Tx ring. The Tx buffer address is filled in as
      * needed, but we do need to clear the upper ownership bit.
      */
     lp->cur_tx = 0;
     for (i = 0; i < TX_RING_SIZE; i++) {
 	lp->tx_ring[i].base = 0;
 	lp->tx_ring[i].status = 0;
     }

     /*
      * Setup Init Block.
      */
     PCNET_DEBUG1("Init block at 0x%p: MAC", &lp->init_block);

     for (i = 0; i < 6; i++) {
 	lp->init_block.phys_addr[i] = dev->enetaddr[i];
 	PCNET_DEBUG1(" %02x", lp->init_block.phys_addr[i]);
     }

     lp->init_block.tlen_rlen = cpu_to_le16(TX_RING_LEN_BITS |
 					   RX_RING_LEN_BITS);
     lp->init_block.rx_ring = PCI_TO_MEM_LE(dev, lp->rx_ring);
     lp->init_block.tx_ring = PCI_TO_MEM_LE(dev, lp->tx_ring);

     PCNET_DEBUG1("\ntlen_rlen=0x%x rx_ring=0x%x tx_ring=0x%x\n",
 	   lp->init_block.tlen_rlen,
 	   lp->init_block.rx_ring, lp->init_block.tx_ring);

     /*
      * Tell the controller where the Init Block is located.
      */
     addr = PCI_TO_MEM(dev, &lp->init_block);
     pcnet_write_csr(dev, 1, addr & 0xffff);
     pcnet_write_csr(dev, 2, (addr >> 16) & 0xffff);

     pcnet_write_csr (dev, 4, 0x0915);
     pcnet_write_csr (dev, 0, 0x0001); /* start */

     /* Wait for Init Done bit */
     for (i = 10000; i > 0; i--) {
 	if (pcnet_read_csr (dev, 0) & 0x0100)
 	    break;
 	udelay(10);
     }
     if (i <= 0) {
 	printf("%s: TIMEOUT: controller init failed\n", dev->name);
 	pcnet_reset (dev);
 	return 0;
     }

     /*
      * Finally start network controller operation.
      */
     pcnet_write_csr (dev, 0, 0x0002);

     return 1;
 }

 static int pcnet_send(struct eth_device* dev, volatile void *packet, int pkt_len)
 {
     int i, status;
     struct pcnet_tx_head *entry = &lp->tx_ring[lp->cur_tx];

     PCNET_DEBUG2("Tx%d: %d bytes from 0x%p ", lp->cur_tx, pkt_len, packet);

     /* Wait for completion by testing the OWN bit */
     for (i = 1000; i > 0; i--) {
 	status = le16_to_cpu(entry->status);
 	if ((status & 0x8000) == 0)
 	    break;
 	udelay(100);
 	PCNET_DEBUG2(".");
     }
     if (i <= 0) {
 	printf("%s: TIMEOUT: Tx%d failed (status = 0x%x)\n",
 	       dev->name, lp->cur_tx, status);
 	pkt_len = 0;
 	goto failure;
     }

     /*
      * Setup Tx ring. Caution: the write order is important here,
      * set the status with the "ownership" bits last.
      */
     status = 0x8300;
     entry->length = le16_to_cpu(-pkt_len);
     entry->misc   = 0x00000000;
     entry->base   = PCI_TO_MEM_LE(dev, packet);
     entry->status = le16_to_cpu(status);

     /* Trigger an immediate send poll. */
     pcnet_write_csr (dev, 0, 0x0008);

  failure:
     if (++lp->cur_tx >= TX_RING_SIZE)
 	lp->cur_tx = 0;

     PCNET_DEBUG2("done\n");
     return pkt_len;
 }

 static int pcnet_recv(struct eth_device* dev)
 {
     struct pcnet_rx_head *entry;
     int pkt_len = 0;
     u16 status;

     while (1) {
 	entry = &lp->rx_ring[lp->cur_rx];
 	/*
 	 * If we own the next entry, it's a new packet. Send it up.
 	 */
 	if (((status = le16_to_cpu(entry->status)) & 0x8000) != 0) {
 	    break;
 	}
 	status >>= 8;

 	if (status != 0x03) {	/* There was an error. */

 	    printf("%s: Rx%d", dev->name, lp->cur_rx);
 	    PCNET_DEBUG1(" (status=0x%x)", status);
 	    if (status & 0x20) printf(" Frame");
 	    if (status & 0x10) printf(" Overflow");
 	    if (status & 0x08) printf(" CRC");
 	    if (status & 0x04) printf(" Fifo");
 	    printf(" Error\n");
 	    entry->status &= le16_to_cpu(0x03ff);

 	} else {

 	    pkt_len = (le32_to_cpu(entry->msg_length) & 0xfff) - 4;
 	    if (pkt_len < 60) {
 		printf("%s: Rx%d: invalid packet length %d\n",
 		       dev->name, lp->cur_rx, pkt_len);
 	    } else {
 		NetReceive(lp->rx_buf[lp->cur_rx], pkt_len);
 		PCNET_DEBUG2("Rx%d: %d bytes from 0x%p\n",
 		       lp->cur_rx, pkt_len, lp->rx_buf[lp->cur_rx]);
 	    }
 	}
 	entry->status |= cpu_to_le16(0x8000);

 	if (++lp->cur_rx >= RX_RING_SIZE)
 	    lp->cur_rx = 0;
     }
     return pkt_len;
 }

 static void pcnet_halt(struct eth_device* dev)
 {
     int i;

     PCNET_DEBUG1("%s: pcnet_halt...\n", dev->name);

     /* Reset the PCnet controller */
     pcnet_reset (dev);

     /* Wait for Stop bit */
     for (i = 1000; i > 0; i--) {
 	if (pcnet_read_csr (dev, 0) & 0x4)
 	    break;
 	udelay(10);
     }
     if (i <= 0) {
 	printf("%s: TIMEOUT: controller reset failed\n", dev->name);
     }
 }

 #endif
	/*
	* (C) Copyright 2002 Wolfgang Grandegger, wg@denx.de.
	*
	* This driver for AMD PCnet network controllers is derived from the
	* Linux driver pcnet32.c written 1996-1999 by Thomas Bogendoerfer.
	*
	* See file CREDITS for list of people who contributed to this
	* project.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation; either version 2 of
	* the License, or (at your option) any later version.
	*
	* 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, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	* MA 02111-1307 USA
	*/

	#include <common.h>
	#include <malloc.h>
	#include <net.h>
	#include <asm/io.h>
	#include <pci.h>

	#if 0
	#define PCNET_DEBUG_LEVEL 0 /* 0=off, 1=init, 2=rx/tx */
	#endif

	#if PCNET_DEBUG_LEVEL > 0
	#define PCNET_DEBUG1(fmt,args...) printf (fmt ,##args)
	#if PCNET_DEBUG_LEVEL > 1
	#define PCNET_DEBUG2(fmt,args...) printf (fmt ,##args)
	#else
	#define PCNET_DEBUG2(fmt,args...)
	#endif
	#else
	#define PCNET_DEBUG1(fmt,args...)
	#define PCNET_DEBUG2(fmt,args...)
	#endif

	#if (CONFIG_COMMANDS & CFG_CMD_NET) && defined(CONFIG_NET_MULTI) \
	&& defined(CONFIG_PCNET)

	#if !defined(CONF_PCNET_79C973) && defined(CONF_PCNET_79C975)
	#error "Macro for PCnet chip version is not defined!"
	#endif

	/*
	* Set the number of Tx and Rx buffers, using Log_2(# buffers).
	* Reasonable default values are 4 Tx buffers, and 16 Rx buffers.
	* That translates to 2 (4 == 2^^2) and 4 (16 == 2^^4).
	*/
	#define PCNET_LOG_TX_BUFFERS 0
	#define PCNET_LOG_RX_BUFFERS 2

	#define TX_RING_SIZE (1 << (PCNET_LOG_TX_BUFFERS))
	#define TX_RING_LEN_BITS ((PCNET_LOG_TX_BUFFERS) << 12)

	#define RX_RING_SIZE (1 << (PCNET_LOG_RX_BUFFERS))
	#define RX_RING_LEN_BITS ((PCNET_LOG_RX_BUFFERS) << 4)

	#define PKT_BUF_SZ 1544

	/* The PCNET Rx and Tx ring descriptors. */
	struct pcnet_rx_head {
	u32 base;
	s16 buf_length;
	s16 status;
	u32 msg_length;
	u32 reserved;
	};

	struct pcnet_tx_head {
	u32 base;
	s16 length;
	s16 status;
	u32 misc;
	u32 reserved;
	};

	/* The PCNET 32-Bit initialization block, described in databook. */
	struct pcnet_init_block {
	u16 mode;
	u16 tlen_rlen;
	u8 phys_addr[6];
	u16 reserved;
	u32 filter[2];
	/* Receive and transmit ring base, along with extra bits. */
	u32 rx_ring;
	u32 tx_ring;
	u32 reserved2;
	};

	typedef struct pcnet_priv {
	struct pcnet_rx_head rx_ring[RX_RING_SIZE];
	struct pcnet_tx_head tx_ring[TX_RING_SIZE];
	struct pcnet_init_block init_block;
	/* Receive Buffer space */
	unsigned char rx_buf[RX_RING_SIZE][PKT_BUF_SZ + 4];
	int cur_rx;
	int cur_tx;
	} pcnet_priv_t;

	static pcnet_priv_t *lp;

	/* Offsets from base I/O address for WIO mode */
	#define PCNET_RDP 0x10
	#define PCNET_RAP 0x12
	#define PCNET_RESET 0x14
	#define PCNET_BDP 0x16

	static u16 pcnet_read_csr (struct eth_device *dev, int index)
	{
	outw (index, dev->iobase+PCNET_RAP);
	return inw (dev->iobase+PCNET_RDP);
	}

	static void pcnet_write_csr (struct eth_device *dev, int index, u16 val)
	{
	outw (index, dev->iobase+PCNET_RAP);
	outw (val, dev->iobase+PCNET_RDP);
	}

	static u16 pcnet_read_bcr (struct eth_device *dev, int index)
	{
	outw (index, dev->iobase+PCNET_RAP);
	return inw (dev->iobase+PCNET_BDP);
	}

	static void pcnet_write_bcr (struct eth_device *dev, int index, u16 val)
	{
	outw (index, dev->iobase+PCNET_RAP);
	outw (val, dev->iobase+PCNET_BDP);
	}

	static void pcnet_reset (struct eth_device *dev)
	{
	inw (dev->iobase+PCNET_RESET);
	}

	static int pcnet_check (struct eth_device *dev)
	{
	outw (88, dev->iobase+PCNET_RAP);
	return (inw (dev->iobase+PCNET_RAP) == 88);
	}

	static int pcnet_init( struct eth_device* dev, bd_t *bis);
	static int pcnet_send (struct eth_device* dev, volatile void *packet,
	int length);
	static int pcnet_recv (struct eth_device* dev);
	static void pcnet_halt (struct eth_device* dev);
	static int pcnet_probe(struct eth_device* dev, bd_t *bis, int dev_num);

	#define PCI_TO_MEM(d,a) pci_phys_to_mem((pci_dev_t)d->priv, (u_long)(a))
	#define PCI_TO_MEM_LE(d,a) (u32)(cpu_to_le32(PCI_TO_MEM(d,a)))

	static struct pci_device_id supported[] = {
	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_LANCE },
	{ }
	};


	int pcnet_initialize(bd_t *bis)
	{
	pci_dev_t devbusfn;
	struct eth_device* dev;
	u16 command, status;
	int dev_nr = 0;

	PCNET_DEBUG1("\npcnet_initialize...\n");

	for (dev_nr = 0; ; dev_nr++) {

	/*
	* Find the PCnet PCI device(s).
	*/
	if ((devbusfn = pci_find_devices(supported, dev_nr)) < 0) {
	break;
	}

	/*
	* Allocate and pre-fill the device structure.
	*/
	dev = (struct eth_device) malloc(sizeof dev);
	dev->priv = (void *)devbusfn;
	sprintf(dev->name, "pcnet#%d", dev_nr);

	/*
	* Setup the PCI device.
	*/
	pci_read_config_dword(devbusfn, PCI_BASE_ADDRESS_0, (unsigned int *)&dev->iobase);
	dev->iobase &= ~0xf;

	PCNET_DEBUG1("%s: devbusfn=0x%x iobase=0x%x: ",
	dev->name, devbusfn, dev->iobase);

	command = PCI_COMMAND_IO \| PCI_COMMAND_MASTER;
	pci_write_config_word(devbusfn, PCI_COMMAND, command);
	pci_read_config_word(devbusfn, PCI_COMMAND, &status);
	if ((status & command) != command) {
	printf("%s: Couldn't enable IO access or Bus Mastering\n",
	dev->name);
	free(dev);
	continue;
	}

	pci_write_config_byte(devbusfn, PCI_LATENCY_TIMER, 0x40);

	/*
	* Probe the PCnet chip.
	*/
	if (pcnet_probe(dev, bis, dev_nr) < 0) {
	free(dev);
	continue;
	}

	/*
	* Setup device structure and register the driver.
	*/
	dev->init = pcnet_init;
	dev->halt = pcnet_halt;
	dev->send = pcnet_send;
	dev->recv = pcnet_recv;

	eth_register(dev);
	}

	udelay(10 * 1000);

	return dev_nr;
	}

	static int pcnet_probe(struct eth_device* dev, bd_t *bis, int dev_nr)
	{
	int chip_version;
	char *chipname;
	#ifdef PCNET_HAS_PROM
	int i;
	#endif

	/* Reset the PCnet controller */
	pcnet_reset(dev);

	/* Check if register access is working */
	if (pcnet_read_csr(dev, 0) != 4 \|\| !pcnet_check(dev)) {
	printf("%s: CSR register access check failed\n", dev->name);
	return -1;
	}

	/* Identify the chip */
	chip_version = pcnet_read_csr(dev, 88) \| (pcnet_read_csr(dev,89) << 16);
	if ((chip_version & 0xfff) != 0x003)
	return -1;
	chip_version = (chip_version >> 12) & 0xffff;
	switch (chip_version) {
	#ifdef CONFIG_PCNET_79C973
	case 0x2625:
	chipname = "PCnet/FAST III 79C973"; /* PCI */
	break;
	#endif
	#ifdef CONFIG_PCNET_79C975
	case 0x2627:
	chipname = "PCnet/FAST III 79C975"; /* PCI */
	break;
	#endif
	default:
	printf("%s: PCnet version %#x not supported\n",
	dev->name, chip_version);
	return -1;
	}

	PCNET_DEBUG1("AMD %s\n", chipname);

	#ifdef PCNET_HAS_PROM
	/*
	* In most chips, after a chip reset, the ethernet address is read from
	* the station address PROM at the base address and programmed into the
	* "Physical Address Registers" CSR12-14.
	*/
	for (i = 0; i < 3; i++) {
	unsigned int val;
	val = pcnet_read_csr(dev, i+12) & 0x0ffff;
	/* There may be endianness issues here. */
	dev->enetaddr[2*i ] = val & 0x0ff;
	dev->enetaddr[2*i+1] = (val >> 8) & 0x0ff;
	}
	#endif /* PCNET_HAS_PROM */

	return 0;
	}

	static int pcnet_init(struct eth_device* dev, bd_t *bis)
	{
	int i, val;
	u32 addr;

	PCNET_DEBUG1("%s: pcnet_init...\n", dev->name);

	/* Switch pcnet to 32bit mode */
	pcnet_write_bcr (dev, 20, 2);

	#ifdef CONFIG_PN62
	/* Setup LED registers */
	val = pcnet_read_bcr (dev, 2) \| 0x1000;
	pcnet_write_bcr (dev, 2, val); /* enable LEDPE */
	pcnet_write_bcr (dev, 4, 0x5080); /* 100MBit */
	pcnet_write_bcr (dev, 5, 0x40c0); /* LNKSE */
	pcnet_write_bcr (dev, 6, 0x4090); /* TX Activity */
	pcnet_write_bcr (dev, 7, 0x4084); /* RX Activity */
	#endif

	/* Set/reset autoselect bit */
	val = pcnet_read_bcr (dev, 2) & ~2;
	val \|= 2;
	pcnet_write_bcr (dev, 2, val);

	/* Enable auto negotiate, setup, disable fd */
	val = pcnet_read_bcr(dev, 32) & ~0x98;
	val \|= 0x20;
	pcnet_write_bcr(dev, 32, val);

	/*
	* We only maintain one structure because the drivers will never
	* be used concurrently. In 32bit mode the RX and TX ring entries
	* must be aligned on 16-byte boundaries.
	*/
	if (lp == NULL) {
	addr = (u32)malloc(sizeof(pcnet_priv_t) + 0x10);
	addr = (addr + 0xf) & ~0xf;
	lp = (pcnet_priv_t *)addr;
	}

	lp->init_block.mode = cpu_to_le16(0x0000);
	lp->init_block.filter[0] = 0x00000000;
	lp->init_block.filter[1] = 0x00000000;

	/*
	* Initialize the Rx ring.
	*/
	lp->cur_rx = 0;
	for (i = 0; i < RX_RING_SIZE; i++) {
	lp->rx_ring[i].base = PCI_TO_MEM_LE(dev, lp->rx_buf[i]);
	lp->rx_ring[i].buf_length = cpu_to_le16(-PKT_BUF_SZ);
	lp->rx_ring[i].status = cpu_to_le16(0x8000);
	PCNET_DEBUG1("Rx%d: base=0x%x buf_length=0x%hx status=0x%hx\n",
	i, lp->rx_ring[i].base, lp->rx_ring[i].buf_length,
	lp->rx_ring[i].status);
	}

	/*
	* Initialize the Tx ring. The Tx buffer address is filled in as
	* needed, but we do need to clear the upper ownership bit.
	*/
	lp->cur_tx = 0;
	for (i = 0; i < TX_RING_SIZE; i++) {
	lp->tx_ring[i].base = 0;
	lp->tx_ring[i].status = 0;
	}

	/*
	* Setup Init Block.
	*/
	PCNET_DEBUG1("Init block at 0x%p: MAC", &lp->init_block);

	for (i = 0; i < 6; i++) {
	lp->init_block.phys_addr[i] = dev->enetaddr[i];
	PCNET_DEBUG1(" %02x", lp->init_block.phys_addr[i]);
	}

	lp->init_block.tlen_rlen = cpu_to_le16(TX_RING_LEN_BITS \|
	RX_RING_LEN_BITS);
	lp->init_block.rx_ring = PCI_TO_MEM_LE(dev, lp->rx_ring);
	lp->init_block.tx_ring = PCI_TO_MEM_LE(dev, lp->tx_ring);

	PCNET_DEBUG1("\ntlen_rlen=0x%x rx_ring=0x%x tx_ring=0x%x\n",
	lp->init_block.tlen_rlen,
	lp->init_block.rx_ring, lp->init_block.tx_ring);

	/*
	* Tell the controller where the Init Block is located.
	*/
	addr = PCI_TO_MEM(dev, &lp->init_block);
	pcnet_write_csr(dev, 1, addr & 0xffff);
	pcnet_write_csr(dev, 2, (addr >> 16) & 0xffff);

	pcnet_write_csr (dev, 4, 0x0915);
	pcnet_write_csr (dev, 0, 0x0001); /* start */

	/* Wait for Init Done bit */
	for (i = 10000; i > 0; i--) {
	if (pcnet_read_csr (dev, 0) & 0x0100)
	break;
	udelay(10);
	}
	if (i <= 0) {
	printf("%s: TIMEOUT: controller init failed\n", dev->name);
	pcnet_reset (dev);
	return 0;
	}

	/*
	* Finally start network controller operation.
	*/
	pcnet_write_csr (dev, 0, 0x0002);

	return 1;
	}

	static int pcnet_send(struct eth_device* dev, volatile void *packet, int pkt_len)
	{
	int i, status;
	struct pcnet_tx_head *entry = &lp->tx_ring[lp->cur_tx];

	PCNET_DEBUG2("Tx%d: %d bytes from 0x%p ", lp->cur_tx, pkt_len, packet);

	/* Wait for completion by testing the OWN bit */
	for (i = 1000; i > 0; i--) {
	status = le16_to_cpu(entry->status);
	if ((status & 0x8000) == 0)
	break;
	udelay(100);
	PCNET_DEBUG2(".");
	}
	if (i <= 0) {
	printf("%s: TIMEOUT: Tx%d failed (status = 0x%x)\n",
	dev->name, lp->cur_tx, status);
	pkt_len = 0;
	goto failure;
	}

	/*
	* Setup Tx ring. Caution: the write order is important here,
	* set the status with the "ownership" bits last.
	*/
	status = 0x8300;
	entry->length = le16_to_cpu(-pkt_len);
	entry->misc = 0x00000000;
	entry->base = PCI_TO_MEM_LE(dev, packet);
	entry->status = le16_to_cpu(status);

	/* Trigger an immediate send poll. */
	pcnet_write_csr (dev, 0, 0x0008);

	failure:
	if (++lp->cur_tx >= TX_RING_SIZE)
	lp->cur_tx = 0;

	PCNET_DEBUG2("done\n");
	return pkt_len;
	}

	static int pcnet_recv(struct eth_device* dev)
	{
	struct pcnet_rx_head *entry;
	int pkt_len = 0;
	u16 status;

	while (1) {
	entry = &lp->rx_ring[lp->cur_rx];
	/*
	* If we own the next entry, it's a new packet. Send it up.
	*/
	if (((status = le16_to_cpu(entry->status)) & 0x8000) != 0) {
	break;
	}
	status >>= 8;

	if (status != 0x03) { /* There was an error. */

	printf("%s: Rx%d", dev->name, lp->cur_rx);
	PCNET_DEBUG1(" (status=0x%x)", status);
	if (status & 0x20) printf(" Frame");
	if (status & 0x10) printf(" Overflow");
	if (status & 0x08) printf(" CRC");
	if (status & 0x04) printf(" Fifo");
	printf(" Error\n");
	entry->status &= le16_to_cpu(0x03ff);

	} else {

	pkt_len = (le32_to_cpu(entry->msg_length) & 0xfff) - 4;
	if (pkt_len < 60) {
	printf("%s: Rx%d: invalid packet length %d\n",
	dev->name, lp->cur_rx, pkt_len);
	} else {
	NetReceive(lp->rx_buf[lp->cur_rx], pkt_len);
	PCNET_DEBUG2("Rx%d: %d bytes from 0x%p\n",
	lp->cur_rx, pkt_len, lp->rx_buf[lp->cur_rx]);
	}
	}
	entry->status \|= cpu_to_le16(0x8000);

	if (++lp->cur_rx >= RX_RING_SIZE)
	lp->cur_rx = 0;
	}
	return pkt_len;
	}

	static void pcnet_halt(struct eth_device* dev)
	{
	int i;

	PCNET_DEBUG1("%s: pcnet_halt...\n", dev->name);

	/* Reset the PCnet controller */
	pcnet_reset (dev);

	/* Wait for Stop bit */
	for (i = 1000; i > 0; i--) {
	if (pcnet_read_csr (dev, 0) & 0x4)
	break;
	udelay(10);
	}
	if (i <= 0) {
	printf("%s: TIMEOUT: controller reset failed\n", dev->name);
	}
	}

	#endif