[velocity] Rewrite VIA Velocity driver

Signed-off-by: Adrian Jamróz <adrian.jamroz@gmail.com>
Modified-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 807 insertions, 0 deletions

diff --git a/src/drivers/net/velocity.c b/src/drivers/net/velocity.c
new file mode 100644
index 00000000..6d518520
--- /dev/null
+++ b/src/drivers/net/velocity.c
@@ -0,0 +1,807 @@
+/*
+ * Copyright (C) 2012 Adrian Jamróz <adrian.jamroz@gmail.com>
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <byteswap.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/if_ether.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/malloc.h>
+#include <ipxe/pci.h>
+#include <ipxe/mii.h>
+#include "velocity.h"
+
+#define	velocity_setbit(_reg, _mask)	writeb ( readb ( _reg ) | _mask, _reg )
+#define virt_to_le32bus(x)		( cpu_to_le32 ( virt_to_bus ( x ) ) )
+
+/** @file
+ *
+ * VIA Velocity network driver
+ *
+ */
+
+/******************************************************************************
+ *
+ * MII interface
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Stop MII auto-polling
+ *
+ * @v vlc	Velocity device
+ * @ret	rc	Return status code
+ */
+static int velocity_autopoll_stop ( struct velocity_nic *vlc ) {
+	int timeout = VELOCITY_TIMEOUT_US;
+
+	/* Disable MII auto polling */
+	writeb ( 0, vlc->regs + VELOCITY_MIICR );
+
+	/* Wait for disabling to take effect */
+	while ( timeout-- ) {
+		udelay ( 1 );
+		if ( readb ( vlc->regs + VELOCITY_MIISR ) &
+		             VELOCITY_MIISR_IDLE )
+			return 0;
+	}
+
+	DBGC ( vlc, "MII autopoll stop timeout\n" );
+	return -ETIMEDOUT;
+}
+
+/**
+ * Start MII auto-polling
+ *
+ * @v vlc	Velocity device
+ * @ret rc	Return status code
+ */
+static int velocity_autopoll_start ( struct velocity_nic *vlc ) {
+	int timeout = VELOCITY_TIMEOUT_US;
+
+	/* Enable MII auto polling */
+	writeb ( VELOCITY_MIICR_MAUTO, vlc->regs + VELOCITY_MIICR );
+
+	/* Wait for enabling to take effect */
+	while ( timeout-- ) {
+		udelay ( 1 );
+		if ( ( readb ( vlc->regs + VELOCITY_MIISR ) &
+		       VELOCITY_MIISR_IDLE ) == 0 )
+			return 0;
+	}
+
+	DBGC ( vlc, "MII autopoll start timeout\n" );
+	return -ETIMEDOUT;
+}
+
+/**
+ * Read from MII register
+ *
+ * @v mii		MII interface
+ * @v reg		Register address
+ * @ret value		Data read, or negative error
+ */
+static int velocity_mii_read ( struct mii_interface *mii, unsigned int reg ) {
+	struct velocity_nic *vlc =
+		container_of ( mii, struct velocity_nic, mii );
+	int timeout = VELOCITY_TIMEOUT_US;
+	int result;
+
+	DBGC2 ( vlc, "VELOCITY %p MII read reg %d\n", vlc, reg );
+
+	/* Disable autopolling before we can access MII */
+	velocity_autopoll_stop ( vlc );
+
+	/* Send read command and address */
+	writeb ( reg, vlc->regs + VELOCITY_MIIADDR );
+	velocity_setbit ( vlc->regs + VELOCITY_MIICR, VELOCITY_MIICR_RCMD );
+
+	/* Wait for read to complete */
+	while ( timeout-- ) {
+		udelay ( 1 );
+		if ( ( readb ( vlc->regs + VELOCITY_MIICR ) &
+		       VELOCITY_MIICR_RCMD ) == 0 ) {
+			result = readw ( vlc->regs + VELOCITY_MIIDATA );
+			velocity_autopoll_start ( vlc );
+			return result;
+		}
+	}
+
+	/* Restart autopolling */
+	velocity_autopoll_start ( vlc );
+
+	DBGC ( vlc, "MII read timeout\n" );
+	return -ETIMEDOUT;
+}
+
+/**
+ * Write to MII register
+ *
+ * @v mii		MII interface
+ * @v reg		Register address
+ * @v data		Data to write
+ * @ret rc		Return status code
+ */
+static int velocity_mii_write ( struct mii_interface *mii, unsigned int reg,
+				unsigned int data) {
+	struct velocity_nic *vlc =
+		container_of ( mii, struct velocity_nic, mii );
+	int timeout = VELOCITY_TIMEOUT_US;
+
+	DBGC2 ( vlc, "VELOCITY %p MII write reg %d data 0x%04x\n",
+			vlc, reg, data );
+
+	/* Disable autopolling before we can access MII */
+	velocity_autopoll_stop ( vlc );
+
+	/* Send write command, data and destination register */
+	writeb ( reg, vlc->regs + VELOCITY_MIIADDR );
+	writew ( data, vlc->regs + VELOCITY_MIIDATA );
+	velocity_setbit ( vlc->regs + VELOCITY_MIICR, VELOCITY_MIICR_WCMD );
+
+	/* Wait for write to complete */
+	while ( timeout-- ) {
+		udelay ( 1 );
+		if ( ( readb ( vlc->regs + VELOCITY_MIICR ) &
+		       VELOCITY_MIICR_WCMD ) == 0 ) {
+			velocity_autopoll_start ( vlc );
+			return 0;
+		}
+	}
+
+	/* Restart autopolling */
+	velocity_autopoll_start ( vlc );
+
+	DBGC ( vlc, "MII write timeout\n" );
+	return -ETIMEDOUT;
+}
+
+/** Velocity MII operations */
+static struct mii_operations velocity_mii_operations = {
+	.read = velocity_mii_read,
+	.write = velocity_mii_write,
+};
+
+/**
+ * Set Link speed 
+ *
+ * @v vlc	Velocity device
+ */
+static void velocity_set_link ( struct velocity_nic *vlc ) {
+	int tmp;
+
+	/* Advertise 1000MBit */
+	tmp = velocity_mii_read ( &vlc->mii, MII_CTRL1000 );
+	tmp |= ADVERTISE_1000FULL | ADVERTISE_1000HALF;
+	velocity_mii_write ( &vlc->mii, MII_CTRL1000, tmp );
+
+	/* Enable GBit operation in MII Control Register */
+	tmp = velocity_mii_read ( &vlc->mii, MII_BMCR );
+	tmp |= BMCR_SPEED1000;
+	velocity_mii_write ( &vlc->mii, MII_BMCR, tmp );
+}
+
+/******************************************************************************
+ *
+ * Device reset
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Reload eeprom contents
+ *
+ * @v vlc		Velocity device
+ */
+static int velocity_reload_eeprom ( struct velocity_nic *vlc ) {
+	int timeout = VELOCITY_TIMEOUT_US;
+
+	/* Initiate reload */
+	velocity_setbit ( vlc->regs + VELOCITY_EECSR, VELOCITY_EECSR_RELOAD );
+
+	/* Wait for reload to complete */
+	while ( timeout-- ) {
+		udelay ( 1 );
+		if ( ( readb ( vlc->regs + VELOCITY_EECSR ) &
+		       VELOCITY_EECSR_RELOAD ) == 0 )
+			return 0;
+	}
+
+	DBGC ( vlc, "VELOCITY %p EEPROM reload timeout\n", vlc );
+	return -ETIMEDOUT;
+}
+
+/**
+ * Reset hardware
+ *
+ * @v vlc		Velocity device
+ * @ret rc		Return status code
+ */
+static int velocity_reset ( struct velocity_nic *vlc ) {
+	int timeout = VELOCITY_TIMEOUT_US;
+	uint8_t tmp;
+
+	DBGC ( vlc, "VELOCITY %p reset\n", vlc );
+
+	/* clear sticky Power state bits */
+	tmp = readb ( vlc->regs + VELOCITY_STICKY );
+	tmp &= ~( VELOCITY_STICKY_DS0 | VELOCITY_STICKY_DS1 );
+	writeb ( tmp, vlc->regs + VELOCITY_STICKY );
+
+	/* clear PACPI, which might have been enabled by the EEPROM reload */
+	tmp = readb ( vlc->regs + VELOCITY_CFGA );
+	tmp &= ~VELOCITY_CFGA_PACPI;
+	writeb ( tmp, vlc->regs + VELOCITY_CFGA );
+
+	velocity_setbit ( vlc->regs + VELOCITY_CRS1, VELOCITY_CR1_SFRST );
+
+	/* Wait for reset to complete */
+	while ( timeout-- ) {
+		udelay ( 1 );
+		if ( ( readb ( vlc->regs + VELOCITY_CRS1 ) &
+		       VELOCITY_CR1_SFRST ) == 0 )
+			return 0;
+	}
+
+	return -EINVAL;
+}
+
+/******************************************************************************
+ *
+ * Link state
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Check link state
+ *
+ * @v netdev		Network device
+ */
+static void velocity_check_link ( struct net_device *netdev ) {
+	struct velocity_nic *vlc = netdev->priv;
+
+	if ( readb ( vlc->regs + VELOCITY_PHYSTS0 ) & VELOCITY_PHYSTS0_LINK ) {
+		netdev_link_up ( netdev );
+		DBGC ( vlc, "VELOCITY %p link up\n", vlc );
+	} else {
+		netdev_link_down ( netdev );
+		DBGC ( vlc, "VELOCITY %p link down\n", vlc );
+	}
+
+	/* The card disables auto-poll after a link change */
+	velocity_autopoll_start ( vlc );
+}
+
+/******************************************************************************
+ *
+ * Network device interface
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Allocate descriptor rings
+ *
+ * @v vlc	Velocity device
+ * @ret rc	Return status code
+ */
+static int velocity_alloc_rings ( struct velocity_nic *vlc ) {
+	int rc = 0;
+
+	/* Allocate RX descriptor ring */
+	vlc->rx_prod = 0;
+	vlc->rx_cons = 0;
+	vlc->rx_commit = 0;
+	vlc->rx_ring = malloc_dma ( VELOCITY_RXDESC_SIZE, VELOCITY_RING_ALIGN );
+	if ( ! vlc->rx_ring )
+		return -ENOMEM;
+
+	memset ( vlc->rx_ring, 0, VELOCITY_RXDESC_SIZE );
+
+	DBGC2 ( vlc, "VELOCITY %p RX ring start address: %p(phys: %#08lx)\n",
+	       vlc, vlc->rx_ring, virt_to_bus ( vlc->rx_ring ) );
+
+	/* Allocate TX descriptor ring */
+	vlc->tx_prod = 0;
+	vlc->tx_cons = 0;
+	vlc->tx_ring = malloc_dma ( VELOCITY_TXDESC_SIZE, VELOCITY_RING_ALIGN );
+	if ( ! vlc->tx_ring ) {
+		rc = -ENOMEM;
+		goto err_tx_alloc;
+	}
+
+	memset ( vlc->tx_ring, 0, VELOCITY_TXDESC_SIZE );
+
+	/* Send RX ring to the card */
+	writel ( virt_to_bus ( vlc->rx_ring ),
+	         vlc->regs + VELOCITY_RXDESC_ADDR_LO );
+	writew ( VELOCITY_RXDESC_NUM - 1, vlc->regs + VELOCITY_RXDESCNUM );
+
+	/* Send TX ring to the card */
+	writel ( virt_to_bus ( vlc->tx_ring ),
+	         vlc->regs + VELOCITY_TXDESC_ADDR_LO0 );
+	writew ( VELOCITY_TXDESC_NUM - 1, vlc->regs + VELOCITY_TXDESCNUM );
+
+	DBGC2 ( vlc, "VELOCITY %p TX ring start address: %p(phys: %#08lx)\n",
+	       vlc, vlc->tx_ring, virt_to_bus ( vlc->tx_ring ) );
+
+	return 0;
+
+err_tx_alloc:
+	free_dma ( vlc->rx_ring, VELOCITY_RXDESC_SIZE );
+	return rc;
+}
+
+/**
+ * Refill receive descriptor ring
+ *
+ * @v vlc	Velocity device
+ */
+static void velocity_refill_rx ( struct velocity_nic *vlc ) {
+	struct velocity_rx_descriptor *desc;
+	struct io_buffer *iobuf;
+	int rx_idx, i = 0;
+
+	/* Check for new packets */
+	while ( ( vlc->rx_prod - vlc->rx_cons ) < VELOCITY_RXDESC_NUM ) {
+		iobuf = alloc_iob ( VELOCITY_RX_MAX_LEN );
+
+		/* Memory pressure: try again next poll */
+		if ( ! iobuf )
+			break;
+
+		rx_idx = ( vlc->rx_prod++ % VELOCITY_RXDESC_NUM );
+		desc = &vlc->rx_ring[rx_idx];
+
+		/* Set descrptor fields */
+		desc->des1 = 0;
+		desc->addr = virt_to_le32bus ( iobuf-> data );
+		desc->des2 = cpu_to_le32 (
+		    VELOCITY_DES2_SIZE ( VELOCITY_RX_MAX_LEN - 1 ) |
+		    VELOCITY_DES2_IC );
+
+		vlc->rx_buffs[rx_idx] = iobuf;
+		i++;
+
+		/* Return RX descriptors in blocks of 4 (hw requirement) */
+		if ( rx_idx % 4 == 3 ) {
+			int j;
+			for (j = 0; j < 4; j++) {
+				desc = &vlc->rx_ring[rx_idx - j];
+				desc->des0 = cpu_to_le32 ( VELOCITY_DES0_OWN );
+			}
+			vlc->rx_commit += 4;
+		}
+	}
+
+	wmb();
+
+	if ( vlc->rx_commit ) {
+		writew ( vlc->rx_commit,
+		         vlc->regs + VELOCITY_RXDESC_RESIDUECNT );
+		vlc->rx_commit = 0;
+	}
+
+	if ( i > 0 )
+		DBGC2 ( vlc, "VELOCITY %p refilled %d RX descriptors\n",
+		        vlc, i );
+}
+
+/**
+ * Open network device
+ *
+ * @v netdev		Network device
+ * @ret rc		Return status code
+ */
+static int velocity_open ( struct net_device *netdev ) {
+	struct velocity_nic *vlc = netdev->priv;
+	int rc;
+
+	DBGC ( vlc, "VELOCITY %p open\n", vlc );
+	DBGC ( vlc, "VELOCITY %p regs at: %p\n", vlc, vlc->regs );
+
+	/* Allocate descriptor rings */
+	if ( ( rc = velocity_alloc_rings ( vlc ) ) != 0 )
+		return rc;
+
+	velocity_refill_rx ( vlc );
+
+	/* Enable TX/RX queue */
+	writew ( VELOCITY_TXQCSRS_RUN0, vlc->regs + VELOCITY_TXQCSRS );
+	writew ( VELOCITY_RXQCSR_RUN | VELOCITY_RXQCSR_WAK,
+	         vlc->regs + VELOCITY_RXQCSRS );
+
+	/* Enable interrupts */
+	writeb ( 0xff, vlc->regs + VELOCITY_IMR0 );
+	writeb ( 0xff, vlc->regs + VELOCITY_IMR1 );
+
+	/* Start MAC */
+	writeb ( VELOCITY_CR0_STOP, vlc->regs + VELOCITY_CRC0 );
+	writeb ( VELOCITY_CR1_DPOLL, vlc->regs + VELOCITY_CRC0 );
+	writeb ( VELOCITY_CR0_START | VELOCITY_CR0_TXON | VELOCITY_CR0_RXON,
+	         vlc->regs + VELOCITY_CRS0 );
+
+	/* Receive all packets */
+	writeb ( 0xff, vlc->regs + VELOCITY_RCR );
+
+	/* Set initial link state */
+	velocity_check_link ( netdev );
+
+	velocity_autopoll_start ( vlc );
+
+	DBGC2 ( vlc, "VELOCITY %p CR3 %02x\n",
+	        vlc, readb ( vlc->regs + 0x0B ) );
+
+	return 0;
+}
+
+/**
+ * Close network device
+ *
+ * @v netdev		Network device
+ */
+static void velocity_close ( struct net_device *netdev ) {
+	struct velocity_nic *vlc = netdev->priv;
+	int i;
+
+	/* Stop NIC */
+	writeb ( VELOCITY_CR0_TXON | VELOCITY_CR0_RXON,
+	         vlc->regs + VELOCITY_CRC0 );
+	writeb ( VELOCITY_CR0_STOP, vlc->regs + VELOCITY_CRS0 );
+
+	/* Clear RX ring information */
+	writel ( 0, vlc->regs + VELOCITY_RXDESC_ADDR_LO );
+	writew ( 0, vlc->regs + VELOCITY_RXDESCNUM );
+
+	/* Destroy RX ring */
+	free_dma ( vlc->rx_ring, VELOCITY_RXDESC_SIZE );
+	vlc->rx_ring = NULL;
+	vlc->rx_prod = 0;
+	vlc->rx_cons = 0;
+
+	/* Discard receive buffers */
+	for ( i = 0 ; i < VELOCITY_RXDESC_NUM ; i++ ) {
+		if ( vlc->rx_buffs[i] )
+			free_iob ( vlc->rx_buffs[i] );
+		vlc->rx_buffs[i] = NULL;
+	}
+
+	/* Clear TX ring information */
+	writel ( 0, vlc->regs + VELOCITY_TXDESC_ADDR_LO0 );
+	writew ( 0, vlc->regs + VELOCITY_TXDESCNUM );
+
+	/* Destroy TX ring */
+	free_dma ( vlc->tx_ring, VELOCITY_TXDESC_SIZE );
+	vlc->tx_ring = NULL;
+	vlc->tx_prod = 0;
+	vlc->tx_cons = 0;
+}
+
+/**
+ * Transmit packet
+ *
+ * @v netdev		Network device
+ * @v iobuf		I/O buffer
+ * @ret rc		Return status code
+ */
+static int velocity_transmit ( struct net_device *netdev,
+			       struct io_buffer *iobuf ) {
+	struct velocity_nic *vlc = netdev->priv;
+	struct velocity_tx_descriptor *desc;
+	unsigned int tx_idx;
+
+	/* Pad packet to minimum length */
+	iob_pad ( iobuf, ETH_ZLEN );
+
+	tx_idx = ( vlc->tx_prod++ % VELOCITY_TXDESC_NUM );
+	desc = &vlc->tx_ring[tx_idx];
+
+	/* Set packet size and transfer ownership to NIC */
+	desc->des0 = cpu_to_le32 ( VELOCITY_DES0_OWN |
+	                           VELOCITY_DES2_SIZE ( iob_len ( iobuf ) ) );
+	/* Data in first desc fragment, only desc for packet, generate INT */
+	desc->des1 = cpu_to_le32 ( VELOCITY_DES1_FRAG ( 1 ) |
+	                           VELOCITY_DES1_TCPLS |
+				   VELOCITY_DES1_INTR );
+
+	desc->frags[0].addr = virt_to_le32bus ( iobuf->data );
+	desc->frags[0].des2 = cpu_to_le32 (
+	                      VELOCITY_DES2_SIZE ( iob_len ( iobuf ) ) );
+
+	wmb();
+
+	/* Initiate TX */
+	velocity_setbit ( vlc->regs + VELOCITY_TXQCSRS, VELOCITY_TXQCSRS_WAK0 );
+
+	DBGC2 ( vlc, "VELOCITY %p tx_prod=%d desc=%p iobuf=%p len=%zd\n",
+	        vlc, tx_idx, desc, iobuf->data, iob_len ( iobuf ) );
+
+	return 0;
+}
+
+/**
+ * Poll for received packets.
+ *
+ * @v vlc	Velocity device
+ */
+static void velocity_poll_rx ( struct velocity_nic *vlc ) {
+	struct velocity_rx_descriptor *desc;
+	struct io_buffer *iobuf;
+	int rx_idx;
+	size_t len;
+	uint32_t des0;
+
+	/* Check for packets */
+	while ( vlc->rx_cons != vlc->rx_prod ) {
+		rx_idx = ( vlc->rx_cons % VELOCITY_RXDESC_NUM );
+		desc = &vlc->rx_ring[rx_idx];
+
+		des0 = cpu_to_le32 ( desc->des0 );
+
+		/* Return if descriptor still in use */
+		if ( des0 & VELOCITY_DES0_OWN )
+			return;
+
+		iobuf = vlc->rx_buffs[rx_idx];
+
+		/* Get length, strip CRC */
+		len = VELOCITY_DES0_RMBC ( des0 ) - 4;
+		iob_put ( iobuf, len );
+
+		DBGC2 ( vlc, "VELOCITY %p got packet on idx=%d (prod=%d), len %zd\n",
+		    vlc, rx_idx, vlc->rx_prod % VELOCITY_RXDESC_NUM, len );
+
+		if ( des0 & VELOCITY_DES0_RX_ERR ) {
+			/* Report receive error */
+			netdev_rx_err ( vlc->netdev, iobuf, -EINVAL );
+			DBGC ( vlc, "VELOCITY %p receive error, status: %02x\n",
+			       vlc, des0 );
+		} else if ( des0 & VELOCITY_DES0_RXOK ) {
+			/* Report receive success */
+			netdev_rx( vlc->netdev, iobuf );
+		} else {
+			/* Card indicated neither success nor failure
+			 * Technically this shouldn't happen, but we saw it
+			 * in debugging once. */
+			DBGC ( vlc, "VELOCITY %p RX neither ERR nor OK: %04x\n",
+			       vlc, des0 );
+			DBGC ( vlc, "packet len: %zd\n", len );
+			DBGC_HD ( vlc, iobuf->data, 64 );
+
+			/* we don't know what it is, treat is as an error */
+			netdev_rx_err ( vlc->netdev, iobuf, -EINVAL );
+		}
+
+		vlc->rx_cons++;
+	}
+}
+
+/**
+ * Poll for completed packets.
+ *
+ * @v vlc	Velocity device
+ */
+static void velocity_poll_tx ( struct velocity_nic *vlc ) {
+	struct velocity_tx_descriptor *desc;
+	int tx_idx;
+
+	/* Check for packets */
+	while ( vlc->tx_cons != vlc->tx_prod ) {
+		tx_idx = ( vlc->tx_cons % VELOCITY_TXDESC_NUM );
+		desc = &vlc->tx_ring[tx_idx];
+
+		/* Return if descriptor still in use */
+		if ( le32_to_cpu ( desc->des0 ) & VELOCITY_DES0_OWN )
+			return;
+
+		/* Report errors */
+		if ( le32_to_cpu ( desc->des0 ) & VELOCITY_DES0_TERR ) {
+			netdev_tx_complete_next_err ( vlc->netdev, -EINVAL );
+			return;
+		}
+
+		netdev_tx_complete_next ( vlc->netdev );
+
+		DBGC2 ( vlc, "VELOCITY %p poll_tx cons=%d prod=%d tsr=%04x\n",
+		        vlc, tx_idx, vlc->tx_prod % VELOCITY_TXDESC_NUM,
+			( desc->des0 & 0xffff ) );
+		vlc->tx_cons++;
+	}
+}
+
+/**
+ * Poll for completed and received packets
+ *
+ * @v netdev		Network device
+ */
+static void velocity_poll ( struct net_device *netdev ) {
+	struct velocity_nic *vlc = netdev->priv;
+	uint8_t isr1;
+
+	isr1 = readb ( vlc->regs + VELOCITY_ISR1 );
+
+	/* ACK interrupts */
+	writew ( 0xFFFF, vlc->regs + VELOCITY_ISR0 );
+
+	/* Check for competed packets */
+	velocity_poll_rx ( vlc );
+	velocity_poll_tx ( vlc );
+
+	if ( isr1 & VELOCITY_ISR1_SRCI ) {
+		/* Update linkstate */
+		DBGC2 ( vlc, "VELOCITY %p link status interrupt\n", vlc );
+		velocity_check_link ( netdev );
+	}
+
+	velocity_refill_rx ( vlc );
+
+	/* deal with potential RX stall caused by RX ring underrun */
+	writew ( VELOCITY_RXQCSR_RUN | VELOCITY_RXQCSR_WAK,
+	         vlc->regs + VELOCITY_RXQCSRS );
+}
+
+/**
+ * Enable or disable interrupts
+ *
+ * @v netdev		Network device
+ * @v enable		Interrupts should be enabled
+ */
+static void velocity_irq ( struct net_device *netdev, int enable ) {
+	struct velocity_nic *vlc = netdev->priv;
+
+	DBGC ( vlc, "VELOCITY %p interrupts %s\n", vlc,
+	    enable ? "enable" : "disable" );
+
+	if (enable) {
+		/* Enable interrupts */
+		writeb ( VELOCITY_CR3_GINTMSK1, vlc->regs + VELOCITY_CRS3 );
+	} else {
+		/* Disable interrupts */
+		writeb ( VELOCITY_CR3_GINTMSK1, vlc->regs + VELOCITY_CRC3 );
+	}
+}
+
+/** Velocity network device operations */
+static struct net_device_operations velocity_operations = {
+	.open		= velocity_open,
+	.close		= velocity_close,
+	.transmit	= velocity_transmit,
+	.poll		= velocity_poll,
+	.irq		= velocity_irq,
+};
+
+/******************************************************************************
+ *
+ * PCI interface
+ *
+ ******************************************************************************
+ */
+
+/**
+ * Probe PCI device
+ *
+ * @v pci		PCI device
+ * @ret rc		Return status code
+ */
+static int velocity_probe ( struct pci_device *pci ) {
+	struct net_device *netdev;
+	struct velocity_nic *vlc;
+	int rc;
+
+	/* Allocate and initialise net device */
+	netdev = alloc_etherdev ( sizeof ( *vlc ) );
+	if ( ! netdev ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+	netdev_init ( netdev, &velocity_operations );
+	vlc = netdev->priv;
+	pci_set_drvdata ( pci, netdev );
+	netdev->dev = &pci->dev;
+
+	/* Fix up PCI device */
+	adjust_pci_device ( pci );
+
+	/* Map registers */
+	vlc->regs = ioremap ( pci->membase, VELOCITY_BAR_SIZE );
+	vlc->netdev = netdev;
+
+	/* Reset the NIC */
+	if ( ( rc = velocity_reset ( vlc ) ) != 0 )
+		goto err_reset;
+
+	/* Reload EEPROM */
+	if ( ( rc = velocity_reload_eeprom ( vlc ) ) != 0 )
+		goto err_reset;
+
+	/* Get MAC address */
+	netdev->hw_addr[0] = readb ( vlc->regs + VELOCITY_MAC0 );
+	netdev->hw_addr[1] = readb ( vlc->regs + VELOCITY_MAC1 );
+	netdev->hw_addr[2] = readb ( vlc->regs + VELOCITY_MAC2 );
+	netdev->hw_addr[3] = readb ( vlc->regs + VELOCITY_MAC3 );
+	netdev->hw_addr[4] = readb ( vlc->regs + VELOCITY_MAC4 );
+	netdev->hw_addr[5] = readb ( vlc->regs + VELOCITY_MAC5 );
+
+	/* Initialise and reset MII interface */
+	mii_init ( &vlc->mii, &velocity_mii_operations );
+	if ( ( rc = mii_reset ( &vlc->mii ) ) != 0 ) {
+		DBGC ( vlc, "VELOCITY %p could not reset MII: %s\n",
+		       vlc, strerror ( rc ) );
+		goto err_mii_reset;
+	}
+
+	/* Enable proper link advertising */
+	velocity_set_link ( vlc );
+
+	/* Register network device */
+	if ( ( rc = register_netdev ( netdev ) ) != 0 )
+		goto err_register_netdev;
+
+	return 0;
+
+ err_register_netdev:
+ err_mii_reset:
+	velocity_reset ( vlc );
+ err_reset:
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+ err_alloc:
+	return rc;
+}
+
+/**
+ * Remove PCI device
+ *
+ * @v pci		PCI device
+ */
+static void velocity_remove ( struct pci_device *pci ) {
+	struct net_device *netdev = pci_get_drvdata ( pci );
+	struct velocity_nic *vlc = netdev->priv;
+
+	/* Unregister network device */
+	unregister_netdev ( netdev );
+
+	/* Reset card */
+	velocity_reset ( vlc );
+
+	/* Free network device */
+	netdev_nullify ( netdev );
+	netdev_put ( netdev );
+}
+
+/** Velocity PCI device IDs */
+static struct pci_device_id velocity_nics[] = {
+	PCI_ROM ( 0x1106, 0x3119, "vt6122",	"VIA Velocity", 0 ),
+};
+
+/** Velocity PCI driver */
+struct pci_driver velocity_driver __pci_driver = {
+	.ids = velocity_nics,
+	.id_count = ( sizeof ( velocity_nics ) / sizeof ( velocity_nics[0] ) ),
+	.probe = velocity_probe,
+	.remove = velocity_remove,
+};