drivers/net/pcnet.c - github/trini/u-boot - Gitiles

 /*
  * (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.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */

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

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

 #define PCNET_DEBUG1(fmt,args...)	\
 	debug_cond(PCNET_DEBUG_LEVEL > 0, fmt ,##args)
 #define PCNET_DEBUG2(fmt,args...)	\
 	debug_cond(PCNET_DEBUG_LEVEL > 1, fmt ,##args)

 #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;
 };

 struct pcnet_uncached_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;
 };

 typedef struct pcnet_priv {
 	struct pcnet_uncached_priv *uc;
 	/* 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, 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);

 static inline pci_addr_t pcnet_virt_to_mem(const struct eth_device *dev,
 						void *addr)
 {
 	pci_dev_t devbusfn = (pci_dev_t)(unsigned long)dev->priv;
 	void *virt_addr = addr;

 	return pci_virt_to_mem(devbusfn, virt_addr);
 }

 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;
 	u32 bar;

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

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

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

 		/*
 		 * Allocate and pre-fill the device structure.
 		 */
 		dev = (struct eth_device *)malloc(sizeof(*dev));
 		if (!dev) {
 			printf("pcnet: Can not allocate memory\n");
 			break;
 		}
 		memset(dev, 0, sizeof(*dev));
 		dev->priv = (void *)(unsigned long)devbusfn;
 		sprintf(dev->name, "pcnet#%d", dev_nr);

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

 		PCNET_DEBUG1("%s: devbusfn=0x%x iobase=0x%lx: ",
 			     dev->name, devbusfn, (unsigned long)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) {
 	case 0x2621:
 		chipname = "PCnet/PCI II 79C970A";	/* PCI */
 		break;
 #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)
 {
 	struct pcnet_uncached_priv *uc;
 	int i, val;
 	unsigned long addr;

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

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

 	/* 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);

 	/*
 	 * Enable NOUFLO on supported controllers, with the transmit
 	 * start point set to the full packet. This will cause entire
 	 * packets to be buffered by the ethernet controller before
 	 * transmission, eliminating underflows which are common on
 	 * slower devices. Controllers which do not support NOUFLO will
 	 * simply be left with a larger transmit FIFO threshold.
 	 */
 	val = pcnet_read_bcr(dev, 18);
 	val |= 1 << 11;
 	pcnet_write_bcr(dev, 18, val);
 	val = pcnet_read_csr(dev, 80);
 	val |= 0x3 << 10;
 	pcnet_write_csr(dev, 80, 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 = (unsigned long)malloc(sizeof(pcnet_priv_t) + 0x10);
 		addr = (addr + 0xf) & ~0xf;
 		lp = (pcnet_priv_t *)addr;

 		addr = (unsigned long)memalign(ARCH_DMA_MINALIGN,
 					       sizeof(*lp->uc));
 		flush_dcache_range(addr, addr + sizeof(*lp->uc));
 		addr = UNCACHED_SDRAM(addr);
 		lp->uc = (struct pcnet_uncached_priv *)addr;

 		addr = (unsigned long)memalign(ARCH_DMA_MINALIGN,
 					       sizeof(*lp->rx_buf));
 		flush_dcache_range(addr, addr + sizeof(*lp->rx_buf));
 		lp->rx_buf = (void *)addr;
 	}

 	uc = lp->uc;

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

 	/*
 	 * Initialize the Rx ring.
 	 */
 	lp->cur_rx = 0;
 	for (i = 0; i < RX_RING_SIZE; i++) {
 		addr = pcnet_virt_to_mem(dev, (*lp->rx_buf)[i]);
 		uc->rx_ring[i].base = cpu_to_le32(addr);
 		uc->rx_ring[i].buf_length = cpu_to_le16(-PKT_BUF_SZ);
 		uc->rx_ring[i].status = cpu_to_le16(0x8000);
 		PCNET_DEBUG1
 			("Rx%d: base=0x%x buf_length=0x%hx status=0x%hx\n", i,
 			 uc->rx_ring[i].base, uc->rx_ring[i].buf_length,
 			 uc->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++) {
 		uc->tx_ring[i].base = 0;
 		uc->tx_ring[i].status = 0;
 	}

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

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

 	uc->init_block.tlen_rlen = cpu_to_le16(TX_RING_LEN_BITS |
 					       RX_RING_LEN_BITS);
 	addr = pcnet_virt_to_mem(dev, uc->rx_ring);
 	uc->init_block.rx_ring = cpu_to_le32(addr);
 	addr = pcnet_virt_to_mem(dev, uc->tx_ring);
 	uc->init_block.tx_ring = cpu_to_le32(addr);

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

 	/*
 	 * Tell the controller where the Init Block is located.
 	 */
 	barrier();
 	addr = pcnet_virt_to_mem(dev, &lp->uc->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 -1;
 	}

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

 	return 0;
 }

 static int pcnet_send(struct eth_device *dev, void *packet, int pkt_len)
 {
 	int i, status;
 	u32 addr;
 	struct pcnet_tx_head *entry = &lp->uc->tx_ring[lp->cur_tx];

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

 	flush_dcache_range((unsigned long)packet,
 			   (unsigned long)packet + pkt_len);

 	/* Wait for completion by testing the OWN bit */
 	for (i = 1000; i > 0; i--) {
 		status = readw(&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.
 	 */
 	addr = pcnet_virt_to_mem(dev, packet);
 	writew(-pkt_len, &entry->length);
 	writel(0, &entry->misc);
 	writel(addr, &entry->base);
 	writew(0x8300, &entry->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;
 	unsigned char *buf;
 	int pkt_len = 0;
 	u16 status, err_status;

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

 		if (err_status != 0x03) {	/* There was an error. */
 			printf("%s: Rx%d", dev->name, lp->cur_rx);
 			PCNET_DEBUG1(" (status=0x%x)", err_status);
 			if (err_status & 0x20)
 				printf(" Frame");
 			if (err_status & 0x10)
 				printf(" Overflow");
 			if (err_status & 0x08)
 				printf(" CRC");
 			if (err_status & 0x04)
 				printf(" Fifo");
 			printf(" Error\n");
 			status &= 0x03ff;

 		} else {
 			pkt_len = (readl(&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 {
 				buf = (*lp->rx_buf)[lp->cur_rx];
 				invalidate_dcache_range((unsigned long)buf,
 					(unsigned long)buf + pkt_len);
 				net_process_received_packet(buf, pkt_len);
 				PCNET_DEBUG2("Rx%d: %d bytes from 0x%p\n",
 					     lp->cur_rx, pkt_len, buf);
 			}
 		}

 		status |= 0x8000;
 		writew(status, &entry->status);

 		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);
 }
	/*
	* (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.
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/

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

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

	#define PCNET_DEBUG1(fmt,args...) \
	debug_cond(PCNET_DEBUG_LEVEL > 0, fmt ,##args)
	#define PCNET_DEBUG2(fmt,args...) \
	debug_cond(PCNET_DEBUG_LEVEL > 1, fmt ,##args)

	#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;
	};

	struct pcnet_uncached_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;
	};

	typedef struct pcnet_priv {
	struct pcnet_uncached_priv *uc;
	/* 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, 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);

	static inline pci_addr_t pcnet_virt_to_mem(const struct eth_device *dev,
	void *addr)
	{
	pci_dev_t devbusfn = (pci_dev_t)(unsigned long)dev->priv;
	void *virt_addr = addr;

	return pci_virt_to_mem(devbusfn, virt_addr);
	}

	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;
	u32 bar;

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

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

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

	/*
	* Allocate and pre-fill the device structure.
	*/
	dev = (struct eth_device )malloc(sizeof(dev));
	if (!dev) {
	printf("pcnet: Can not allocate memory\n");
	break;
	}
	memset(dev, 0, sizeof(*dev));
	dev->priv = (void *)(unsigned long)devbusfn;
	sprintf(dev->name, "pcnet#%d", dev_nr);

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

	PCNET_DEBUG1("%s: devbusfn=0x%x iobase=0x%lx: ",
	dev->name, devbusfn, (unsigned long)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) {
	case 0x2621:
	chipname = "PCnet/PCI II 79C970A"; /* PCI */
	break;
	#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)
	{
	struct pcnet_uncached_priv *uc;
	int i, val;
	unsigned long addr;

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

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

	/* 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);

	/*
	* Enable NOUFLO on supported controllers, with the transmit
	* start point set to the full packet. This will cause entire
	* packets to be buffered by the ethernet controller before
	* transmission, eliminating underflows which are common on
	* slower devices. Controllers which do not support NOUFLO will
	* simply be left with a larger transmit FIFO threshold.
	*/
	val = pcnet_read_bcr(dev, 18);
	val \|= 1 << 11;
	pcnet_write_bcr(dev, 18, val);
	val = pcnet_read_csr(dev, 80);
	val \|= 0x3 << 10;
	pcnet_write_csr(dev, 80, 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 = (unsigned long)malloc(sizeof(pcnet_priv_t) + 0x10);
	addr = (addr + 0xf) & ~0xf;
	lp = (pcnet_priv_t *)addr;

	addr = (unsigned long)memalign(ARCH_DMA_MINALIGN,
	sizeof(*lp->uc));
	flush_dcache_range(addr, addr + sizeof(*lp->uc));
	addr = UNCACHED_SDRAM(addr);
	lp->uc = (struct pcnet_uncached_priv *)addr;

	addr = (unsigned long)memalign(ARCH_DMA_MINALIGN,
	sizeof(*lp->rx_buf));
	flush_dcache_range(addr, addr + sizeof(*lp->rx_buf));
	lp->rx_buf = (void *)addr;
	}

	uc = lp->uc;

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

	/*
	* Initialize the Rx ring.
	*/
	lp->cur_rx = 0;
	for (i = 0; i < RX_RING_SIZE; i++) {
	addr = pcnet_virt_to_mem(dev, (*lp->rx_buf)[i]);
	uc->rx_ring[i].base = cpu_to_le32(addr);
	uc->rx_ring[i].buf_length = cpu_to_le16(-PKT_BUF_SZ);
	uc->rx_ring[i].status = cpu_to_le16(0x8000);
	PCNET_DEBUG1
	("Rx%d: base=0x%x buf_length=0x%hx status=0x%hx\n", i,
	uc->rx_ring[i].base, uc->rx_ring[i].buf_length,
	uc->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++) {
	uc->tx_ring[i].base = 0;
	uc->tx_ring[i].status = 0;
	}

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

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

	uc->init_block.tlen_rlen = cpu_to_le16(TX_RING_LEN_BITS \|
	RX_RING_LEN_BITS);
	addr = pcnet_virt_to_mem(dev, uc->rx_ring);
	uc->init_block.rx_ring = cpu_to_le32(addr);
	addr = pcnet_virt_to_mem(dev, uc->tx_ring);
	uc->init_block.tx_ring = cpu_to_le32(addr);

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

	/*
	* Tell the controller where the Init Block is located.
	*/
	barrier();
	addr = pcnet_virt_to_mem(dev, &lp->uc->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 -1;
	}

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

	return 0;
	}

	static int pcnet_send(struct eth_device dev, void packet, int pkt_len)
	{
	int i, status;
	u32 addr;
	struct pcnet_tx_head *entry = &lp->uc->tx_ring[lp->cur_tx];

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

	flush_dcache_range((unsigned long)packet,
	(unsigned long)packet + pkt_len);

	/* Wait for completion by testing the OWN bit */
	for (i = 1000; i > 0; i--) {
	status = readw(&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.
	*/
	addr = pcnet_virt_to_mem(dev, packet);
	writew(-pkt_len, &entry->length);
	writel(0, &entry->misc);
	writel(addr, &entry->base);
	writew(0x8300, &entry->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;
	unsigned char *buf;
	int pkt_len = 0;
	u16 status, err_status;

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

	if (err_status != 0x03) { /* There was an error. */
	printf("%s: Rx%d", dev->name, lp->cur_rx);
	PCNET_DEBUG1(" (status=0x%x)", err_status);
	if (err_status & 0x20)
	printf(" Frame");
	if (err_status & 0x10)
	printf(" Overflow");
	if (err_status & 0x08)
	printf(" CRC");
	if (err_status & 0x04)
	printf(" Fifo");
	printf(" Error\n");
	status &= 0x03ff;

	} else {
	pkt_len = (readl(&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 {
	buf = (*lp->rx_buf)[lp->cur_rx];
	invalidate_dcache_range((unsigned long)buf,
	(unsigned long)buf + pkt_len);
	net_process_received_packet(buf, pkt_len);
	PCNET_DEBUG2("Rx%d: %d bytes from 0x%p\n",
	lp->cur_rx, pkt_len, buf);
	}
	}

	status \|= 0x8000;
	writew(status, &entry->status);

	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);
	}