Subject: [PATCH v6 1/1] Driver for Beckhoff CX5020 EtherCAT master module.

From: Darek Marcinkiewicz <[email-masked]>
Date: Sun, 4 May 2014 12:14:28 +0200

This driver adds support for EtherCAT master module located on CCAT
FPGA found on Beckhoff CX series industrial PCs. The driver exposes
EtherCAT master as an ethernet interface.

EtherCAT is a fieldbus protocol defined on top of ethernet and Beckhoff
CX5020 PCs come with built-in EtherCAT master module located on a FPGA,
which in turn is connected to a PCI bus.

Signed-off-by: Dariusz Marcinkiewicz <[email-masked]>
---
Changes from v5:
  * removal of needless locking on tx path
  * driver makes actual use of tx fifo
  * driver uses descriptors' array instead of descriptor list

Changes from v4: 
  * incorporates Francois Romieu comments
  * fixes typo spotted by Jesper Brouer

Changes from v3:
  * some clarificatoins around buffer allocations

Changes from v2:
  * removed all checkpatch warnings
  * driver makes use of device rx fifo

Changes from v1:
  * added endianess annotation to descriptors' structures
  * killed checkpath warnings about string literals being split into multiple
    lines

 drivers/net/ethernet/Kconfig  |   11 +
 drivers/net/ethernet/Makefile |    1 +
 drivers/net/ethernet/ec_bhf.c |  701 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 713 insertions(+)
 create mode 100644 drivers/net/ethernet/ec_bhf.c

diff --git a/drivers/net/ethernet/Kconfig b/drivers/net/ethernet/Kconfig
index 39b26fe..a93ea15 100644
--- a/drivers/net/ethernet/Kconfig
+++ b/drivers/net/ethernet/Kconfig
@@ -35,6 +35,17 @@ source "drivers/net/ethernet/calxeda/Kconfig"
 source "drivers/net/ethernet/chelsio/Kconfig"
 source "drivers/net/ethernet/cirrus/Kconfig"
 source "drivers/net/ethernet/cisco/Kconfig"
+
+config CX_ECAT
+	tristate "Beckhoff CX5020 EtherCAT master support"
+	---help---
+	  Driver for EtherCAT master module located on CCAT FPGA
+	  that can be found on Beckhoff CX5020, and possibly other of CX
+	  Beckhoff CX series industrial PCs.
+
+	  To compile this driver as a module, choose M here. The module
+	  will be called ec_bhf.
+
 source "drivers/net/ethernet/davicom/Kconfig"
 
 config DNET
diff --git a/drivers/net/ethernet/Makefile b/drivers/net/ethernet/Makefile
index 545d0b3..35190e3 100644
--- a/drivers/net/ethernet/Makefile
+++ b/drivers/net/ethernet/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_NET_CALXEDA_XGMAC) += calxeda/
 obj-$(CONFIG_NET_VENDOR_CHELSIO) += chelsio/
 obj-$(CONFIG_NET_VENDOR_CIRRUS) += cirrus/
 obj-$(CONFIG_NET_VENDOR_CISCO) += cisco/
+obj-$(CONFIG_CX_ECAT) += ec_bhf.o
 obj-$(CONFIG_DM9000) += davicom/
 obj-$(CONFIG_DNET) += dnet.o
 obj-$(CONFIG_NET_VENDOR_DEC) += dec/
diff --git a/drivers/net/ethernet/ec_bhf.c b/drivers/net/ethernet/ec_bhf.c
new file mode 100644
index 0000000..feb40cd
--- /dev/null
+++ b/drivers/net/ethernet/ec_bhf.c
@@ -0,0 +1,701 @@
+ /*
+ * drivers/net/ethernet/beckhoff/ec_bhf.c
+ *
+ * Copyright (C) 2014 Darek Marcinkiewicz <[email-masked]>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+/* This is a driver for EtherCAT master module present on CCAT FPGA.
+ * Those can be found on Bechhoff CX50xx industrial PCs.
+ */
+
+#if 0
+#define DEBUG
+#endif
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ip.h>
+#include <linux/skbuff.h>
+#include <linux/hrtimer.h>
+#include <linux/interrupt.h>
+#include <linux/stat.h>
+
+#define TIMER_INTERVAL_NSEC	20000
+
+#define INFO_BLOCK_SIZE		0x10
+#define INFO_BLOCK_TYPE		0x0
+#define INFO_BLOCK_REV		0x2
+#define INFO_BLOCK_BLK_CNT	0x4
+#define INFO_BLOCK_TX_CHAN	0x4
+#define INFO_BLOCK_RX_CHAN	0x5
+#define INFO_BLOCK_OFFSET	0x8
+
+#define EC_MII_OFFSET		0x4
+#define EC_FIFO_OFFSET		0x8
+#define EC_MAC_OFFSET		0xc
+
+#define MAC_FRAME_ERR_CNT	0x0
+#define MAC_RX_ERR_CNT		0x1
+#define MAC_CRC_ERR_CNT		0x2
+#define MAC_LNK_LST_ERR_CNT	0x3
+#define MAC_TX_FRAME_CNT	0x10
+#define MAC_RX_FRAME_CNT	0x14
+#define MAC_TX_FIFO_LVL		0x20
+#define MAC_DROPPED_FRMS	0x28
+#define MAC_CONNECTED_CCAT_FLAG	0x78
+
+#define MII_MAC_ADDR		0x8
+#define MII_MAC_FILT_FLAG	0xe
+#define MII_LINK_STATUS		0xf
+
+#define FIFO_TX_REG		0x0
+#define FIFO_TX_RESET		0x8
+#define FIFO_RX_REG		0x10
+#define FIFO_RX_ADDR_VALID	(1u << 31)
+#define FIFO_RX_RESET		0x18
+
+#define DMA_CHAN_OFFSET		0x1000
+#define DMA_CHAN_SIZE		0x8
+
+static struct pci_device_id ids[] = {
+	{ PCI_DEVICE(0x15ec, 0x5000), },
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, ids);
+
+struct rx_header {
+#define RXHDR_NEXT_ADDR_MASK	0xffffffu
+#define RXHDR_NEXT_VALID	(1u << 31)
+	__le32 next;
+#define RXHDR_NEXT_RECV_FLAG	0x1
+	__le32 recv;
+#define RXHDR_LEN_MASK		0xfffu
+	__le16 len;
+	__le16 port;
+	__le32 reserved;
+	u8 timestamp[8];
+} __packed;
+
+#define PKT_PAYLOAD_SIZE	0x7e8
+struct rx_desc {
+	struct rx_header header;
+	u8 data[PKT_PAYLOAD_SIZE];
+} __packed;
+
+struct tx_header {
+	__le16 len;
+#define TX_HDR_PORT_0		0x1
+#define TX_HDR_PORT_1		0x2
+	u8 port;
+	u8 ts_enable;
+#define TX_HDR_SENT		0x1
+	__le32 sent;
+	u8 timestamp[8];
+} __packed;
+
+struct tx_desc {
+	struct tx_header header;
+	u8 data[PKT_PAYLOAD_SIZE];
+} __packed;
+
+#define FIFO_SIZE		64
+
+static long polling_frequency = TIMER_INTERVAL_NSEC;
+
+struct bhf_dma {
+	u8 *buf;
+	size_t len;
+	dma_addr_t buf_phys;
+
+	u8 *alloc;
+	size_t alloc_len;
+	dma_addr_t alloc_phys;
+};
+
+struct ec_bhf_priv {
+	struct net_device *net_dev;
+
+	struct pci_dev *dev;
+
+	void * __iomem io;
+	void * __iomem dma_io;
+
+	struct hrtimer hrtimer;
+
+	int tx_dma_chan;
+	int rx_dma_chan;
+	void * __iomem ec_io;
+	void * __iomem fifo_io;
+	void * __iomem mii_io;
+	void * __iomem mac_io;
+
+	struct bhf_dma rx_buf;
+	struct rx_desc *rx_descs;
+	int rx_dnext;
+	int rx_dcount;
+
+	struct bhf_dma tx_buf;
+	struct tx_desc *tx_descs;
+	int tx_dcount;
+	int tx_dnext;
+
+	u64 stat_rx_bytes;
+	u64 stat_tx_bytes;
+};
+
+#define PRIV_TO_DEV(priv) (&(priv)->dev->dev)
+
+#define ETHERCAT_MASTER_ID	0x14
+
+static void ec_bhf_print_status(struct ec_bhf_priv *priv)
+{
+	struct device *dev = PRIV_TO_DEV(priv);
+
+	dev_dbg(dev, "Frame error counter: %d\n",
+		 ioread8(priv->mac_io + MAC_FRAME_ERR_CNT));
+	dev_dbg(dev, "RX error counter: %d\n",
+		 ioread8(priv->mac_io + MAC_RX_ERR_CNT));
+	dev_dbg(dev, "CRC error counter: %d\n",
+		 ioread8(priv->mac_io + MAC_CRC_ERR_CNT));
+	dev_dbg(dev, "TX frame counter: %d\n",
+		 ioread32(priv->mac_io + MAC_TX_FRAME_CNT));
+	dev_dbg(dev, "RX frame counter: %d\n",
+		 ioread32(priv->mac_io + MAC_RX_FRAME_CNT));
+	dev_dbg(dev, "TX fifo level: %d\n",
+		 ioread8(priv->mac_io + MAC_TX_FIFO_LVL));
+	dev_dbg(dev, "Dropped frames: %d\n",
+		 ioread8(priv->mac_io + MAC_DROPPED_FRMS));
+	dev_dbg(dev, "Connected with CCAT slot: %d\n",
+		 ioread8(priv->mac_io + MAC_CONNECTED_CCAT_FLAG));
+	dev_dbg(dev, "Link status: %d\n",
+		 ioread8(priv->mii_io + MII_LINK_STATUS));
+}
+
+static void ec_bhf_reset(struct ec_bhf_priv *priv)
+{
+	iowrite8(0, priv->mac_io + MAC_FRAME_ERR_CNT);
+	iowrite8(0, priv->mac_io + MAC_RX_ERR_CNT);
+	iowrite8(0, priv->mac_io + MAC_CRC_ERR_CNT);
+	iowrite8(0, priv->mac_io + MAC_LNK_LST_ERR_CNT);
+	iowrite32(0, priv->mac_io + MAC_TX_FRAME_CNT);
+	iowrite32(0, priv->mac_io + MAC_RX_FRAME_CNT);
+	iowrite8(0, priv->mac_io + MAC_DROPPED_FRMS);
+
+	iowrite8(0, priv->fifo_io + FIFO_TX_RESET);
+	iowrite8(0, priv->fifo_io + FIFO_RX_RESET);
+
+	iowrite8(0, priv->mac_io + MAC_TX_FIFO_LVL);
+}
+
+static void ec_bhf_send_packet(struct ec_bhf_priv *priv, struct tx_desc *desc)
+{
+	u32 addr = (u8 *)desc - priv->tx_buf.buf;
+	u32 len = le16_to_cpu(desc->header.len) + sizeof(desc->header);
+
+	iowrite32((ALIGN(len, 8) << 24) | addr, priv->fifo_io + FIFO_TX_REG);
+
+	dev_dbg(PRIV_TO_DEV(priv), "Done sending packet\n");
+}
+
+static int ec_bhf_desc_sent(struct tx_desc *desc)
+{
+	return le32_to_cpu(desc->header.sent) & TX_HDR_SENT;
+}
+
+static void ec_bhf_process_tx(struct ec_bhf_priv *priv)
+{
+	if (unlikely(netif_queue_stopped(priv->net_dev))) {
+		struct tx_desc *desc = &priv->tx_descs[priv->tx_dnext];
+		if (ec_bhf_desc_sent(desc))
+			netif_wake_queue(priv->net_dev);
+	}
+}
+
+static int ec_bhf_pkt_received(struct rx_desc *desc)
+{
+	return le32_to_cpu(desc->header.recv) & RXHDR_NEXT_RECV_FLAG;
+}
+
+static void ec_bhf_add_rx_desc(struct ec_bhf_priv *priv, struct rx_desc *desc)
+{
+	iowrite32(FIFO_RX_ADDR_VALID | ((u8 *)(desc) - priv->rx_buf.buf),
+		  priv->fifo_io + FIFO_RX_REG);
+}
+
+static void ec_bhf_process_rx(struct ec_bhf_priv *priv)
+{
+	struct rx_desc *desc = &priv->rx_descs[priv->rx_dnext];
+	struct device *dev = PRIV_TO_DEV(priv);
+
+	while (ec_bhf_pkt_received(desc)) {
+		int pkt_size = (le16_to_cpu(desc->header.len) &
+			       RXHDR_LEN_MASK) - sizeof(struct rx_header) - 4;
+		u8 *data = desc->data;
+		struct sk_buff *skb;
+
+		skb = netdev_alloc_skb_ip_align(priv->net_dev, pkt_size);
+		dev_dbg(dev, "Received packet, size: %d\n", pkt_size);
+
+		if (skb) {
+			memcpy(skb_put(skb, pkt_size), data, pkt_size);
+			skb->protocol = eth_type_trans(skb, priv->net_dev);
+			dev_dbg(dev, "Protocol type: %x\n", skb->protocol);
+
+			netif_rx(skb);
+		} else {
+			dev_err_ratelimited(dev,
+				"Couldn't allocate a skb_buff for a packet of size %u\n",
+				pkt_size);
+		}
+
+		priv->stat_rx_bytes += pkt_size;
+
+		desc->header.recv = 0;
+
+		ec_bhf_add_rx_desc(priv, desc);
+
+		priv->rx_dnext = (priv->rx_dnext + 1) % priv->rx_dcount;
+		desc = &priv->rx_descs[priv->rx_dnext];
+	}
+
+}
+
+static enum hrtimer_restart ec_bhf_timer_fun(struct hrtimer *timer)
+{
+	struct ec_bhf_priv *priv = container_of(timer,
+					struct ec_bhf_priv,
+					hrtimer);
+	ec_bhf_process_rx(priv);
+	ec_bhf_process_tx(priv);
+
+	if (!netif_running(priv->net_dev))
+		return HRTIMER_NORESTART;
+
+	hrtimer_forward_now(timer, ktime_set(0, polling_frequency));
+	return HRTIMER_RESTART;
+}
+
+static int ec_bhf_setup_offsets(struct ec_bhf_priv *priv)
+{
+	struct device *dev = PRIV_TO_DEV(priv);
+	unsigned block_count, i;
+	void * __iomem ec_info;
+
+	dev_info(dev, "Info block:\n");
+	dev_info(dev, "Type of function: %x\n", (unsigned)ioread16(priv->io));
+	dev_info(dev, "Revision of function: %x\n",
+		(unsigned)ioread16(priv->io + INFO_BLOCK_REV));
+
+	block_count = ioread8(priv->io + INFO_BLOCK_BLK_CNT);
+	dev_info(dev, "Number of function blocks: %x\n", block_count);
+
+	for (i = 0; i < block_count; i++) {
+		u16 type = ioread16(priv->io + i * INFO_BLOCK_SIZE +
+				    INFO_BLOCK_TYPE);
+		if (type == ETHERCAT_MASTER_ID)
+			break;
+	}
+	if (i == block_count) {
+		dev_err(dev, "EtherCAT master with DMA block not found\n");
+		return -ENODEV;
+	}
+	dev_info(dev, "EtherCAT master with DMA block found at pos: %d\n", i);
+
+	ec_info = priv->io + i * INFO_BLOCK_SIZE;
+	dev_info(dev, "EtherCAT master revision: %d\n",
+		 ioread16(ec_info + INFO_BLOCK_REV));
+
+	priv->tx_dma_chan = ioread8(ec_info + INFO_BLOCK_TX_CHAN);
+	dev_info(dev, "EtherCAT master tx dma channel: %d\n",
+		 priv->tx_dma_chan);
+
+	priv->rx_dma_chan = ioread8(ec_info + INFO_BLOCK_RX_CHAN);
+	dev_info(dev, "EtherCAT master rx dma channel: %d\n",
+		 priv->rx_dma_chan);
+
+	priv->ec_io = priv->io + ioread32(ec_info + INFO_BLOCK_OFFSET);
+	priv->mii_io = priv->ec_io + ioread32(priv->ec_io + EC_MII_OFFSET);
+	priv->fifo_io = priv->ec_io + ioread32(priv->ec_io + EC_FIFO_OFFSET);
+	priv->mac_io = priv->ec_io + ioread32(priv->ec_io + EC_MAC_OFFSET);
+
+	dev_info(dev,
+		 "EtherCAT block addres: %p, fifo address: %p, mii address: %p, mac address: %p",
+		 priv->ec_io, priv->fifo_io, priv->mii_io, priv->mac_io);
+
+	return 0;
+}
+
+static netdev_tx_t ec_bhf_start_xmit(struct sk_buff *skb,
+				     struct net_device *net_dev)
+{
+	struct ec_bhf_priv *priv = netdev_priv(net_dev);
+	struct tx_desc *desc;
+	unsigned len;
+
+	dev_dbg(PRIV_TO_DEV(priv), "Starting xmit\n");
+
+	desc = &priv->tx_descs[priv->tx_dnext];
+
+	skb_copy_and_csum_dev(skb, desc->data);
+	len = skb->len;
+
+	memset(&desc->header, 0, sizeof(desc->header));
+	desc->header.len = cpu_to_le16(len);
+	desc->header.port = TX_HDR_PORT_0;
+
+	ec_bhf_send_packet(priv, desc);
+
+	priv->tx_dnext = (priv->tx_dnext + 1) % priv->tx_dcount;
+
+	if (!ec_bhf_desc_sent(&priv->tx_descs[priv->tx_dnext])) {
+		dev_info(PRIV_TO_DEV(priv), "Stopping netif queue\n");
+		ec_bhf_print_status(priv);
+
+		netif_stop_queue(net_dev);
+	}
+
+	priv->stat_tx_bytes += len;
+
+	dev_kfree_skb(skb);
+
+	return NETDEV_TX_OK;
+}
+
+static int ec_bhf_alloc_dma_mem(struct ec_bhf_priv *priv,
+				struct bhf_dma *buf,
+				int channel,
+				int size)
+{
+	int offset = channel * DMA_CHAN_SIZE + DMA_CHAN_OFFSET;
+	struct device *dev = PRIV_TO_DEV(priv);
+	u32 mask;
+
+	iowrite32(0xffffffff, priv->dma_io + offset);
+
+	mask = ioread32(priv->dma_io + offset);
+	mask &= 0xfffffffc;
+	dev_info(dev, "Read mask %x for channel %d\n", mask, channel);
+	/* We want to allocate a chunk of memory that is:
+	 * - aligned to the mask we just read
+	 * - is of size 2^mask bytes (at most)
+	 * In order to ensure that we will allocate buffer of
+	 * 2 * 2^mask bytes.
+	 */
+	buf->len = min_t(int, ~mask + 1, size);
+	buf->alloc_len = 2 * buf->len;
+
+	dev_info(dev, "Allocating %d bytes for channel %d",
+		(int)buf->alloc_len, channel);
+	buf->alloc = dma_alloc_coherent(dev, buf->alloc_len,
+					&buf->alloc_phys, GFP_KERNEL);
+	if (buf->alloc == NULL) {
+		dev_info(dev, "Failed to allocate buffer\n");
+		return -ENOMEM;
+	}
+
+	buf->buf_phys = (buf->alloc_phys + buf->len) & mask;
+	buf->buf = buf->alloc + (buf->buf_phys - buf->alloc_phys);
+
+	iowrite32(0, priv->dma_io + offset + 4);
+	iowrite32(buf->buf_phys, priv->dma_io + offset);
+	dev_dbg(dev, "Buffer: %x and read from dev: %x",
+		(unsigned)buf->buf_phys, ioread32(priv->dma_io + offset));
+
+	return 0;
+}
+
+static void ec_bhf_setup_tx_descs(struct ec_bhf_priv *priv)
+{
+	int i = 0;
+
+	priv->tx_dcount = priv->tx_buf.len / sizeof(struct tx_desc);
+	priv->tx_descs = (struct tx_desc *) priv->tx_buf.buf;
+	priv->tx_dnext = 0;
+
+	for (i = 0; i < priv->tx_dcount; i++)
+		priv->tx_descs[i].header.sent = cpu_to_le32(TX_HDR_SENT);
+}
+
+static void ec_bhf_setup_rx_descs(struct ec_bhf_priv *priv)
+{
+	int i;
+
+	priv->rx_dcount = priv->rx_buf.len / sizeof(struct rx_desc);
+	priv->rx_descs = (struct rx_desc *) priv->rx_buf.buf;
+	priv->rx_dnext = 0;
+
+	for (i = 0; i < priv->rx_dcount; i++) {
+		struct rx_desc *desc = &priv->rx_descs[i];
+		u32 next;
+
+		if (i != priv->rx_dcount - 1)
+			next = (u8 *)(desc + 1) - priv->rx_buf.buf;
+		else
+			next = 0;
+		next |= RXHDR_NEXT_VALID;
+		desc->header.next = cpu_to_le32(next);
+		desc->header.recv = 0;
+		ec_bhf_add_rx_desc(priv, desc);
+	}
+}
+
+static int ec_bhf_open(struct net_device *net_dev)
+{
+	struct ec_bhf_priv *priv = netdev_priv(net_dev);
+	struct device *dev = PRIV_TO_DEV(priv);
+	int err = 0;
+
+	dev_info(dev, "Opening device\n");
+
+	ec_bhf_reset(priv);
+
+	err = ec_bhf_alloc_dma_mem(priv, &priv->rx_buf, priv->rx_dma_chan,
+				   FIFO_SIZE * sizeof(struct rx_desc));
+	if (err) {
+		dev_err(dev, "Failed to allocate rx buffer");
+		goto out;
+	}
+	ec_bhf_setup_rx_descs(priv);
+
+	dev_info(dev, "RX buffer allocated, address: %x\n",
+		 (unsigned)priv->rx_buf.buf_phys);
+
+	err = ec_bhf_alloc_dma_mem(priv, &priv->tx_buf, priv->tx_dma_chan,
+				   FIFO_SIZE * sizeof(struct tx_desc));
+	if (err) {
+		dev_err(dev, "Failed to allocate tx buffer");
+		goto error_rx_free;
+	}
+	dev_info(dev, "TX buffer allocated, addres: %x\n",
+		 (unsigned)priv->tx_buf.buf_phys);
+
+	iowrite8(0, priv->mii_io + MII_MAC_FILT_FLAG);
+
+	ec_bhf_setup_tx_descs(priv);
+
+	netif_start_queue(net_dev);
+
+	hrtimer_init(&priv->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	priv->hrtimer.function = ec_bhf_timer_fun;
+	hrtimer_start(&priv->hrtimer,
+		      ktime_set(0, polling_frequency),
+		      HRTIMER_MODE_REL);
+
+	dev_info(PRIV_TO_DEV(priv), "Device open\n");
+
+	ec_bhf_print_status(priv);
+
+	return 0;
+
+error_rx_free:
+	dma_free_coherent(dev, priv->rx_buf.alloc_len, priv->rx_buf.alloc,
+			  priv->rx_buf.alloc_len);
+out:
+	return err;
+}
+
+static int ec_bhf_stop(struct net_device *net_dev)
+{
+	struct ec_bhf_priv *priv = netdev_priv(net_dev);
+	struct device *dev = PRIV_TO_DEV(priv);
+
+	hrtimer_cancel(&priv->hrtimer);
+
+	ec_bhf_reset(priv);
+
+	netif_tx_disable(net_dev);
+
+	dma_free_coherent(dev, priv->tx_buf.alloc_len,
+			  priv->tx_buf.alloc, priv->tx_buf.alloc_phys);
+	dma_free_coherent(dev, priv->rx_buf.alloc_len,
+			  priv->rx_buf.alloc, priv->rx_buf.alloc_phys);
+
+	return 0;
+}
+
+static struct rtnl_link_stats64 *
+ec_bhf_get_stats(struct net_device *net_dev,
+		 struct rtnl_link_stats64 *stats)
+{
+	struct ec_bhf_priv *priv = netdev_priv(net_dev);
+
+	memset(stats, 0, sizeof(*stats));
+
+	stats->rx_errors = ioread8(priv->mac_io + MAC_RX_ERR_CNT) +
+				ioread8(priv->mac_io + MAC_CRC_ERR_CNT) +
+				ioread8(priv->mac_io + MAC_FRAME_ERR_CNT);
+	stats->rx_packets = ioread32(priv->mac_io + MAC_RX_FRAME_CNT);
+	stats->tx_packets = ioread32(priv->mac_io + MAC_TX_FRAME_CNT);
+	stats->rx_dropped = ioread8(priv->mac_io + MAC_DROPPED_FRMS);
+
+	stats->tx_bytes = priv->stat_tx_bytes;
+	stats->rx_bytes = priv->stat_rx_bytes;
+
+	return stats;
+}
+
+static const struct net_device_ops ec_bhf_netdev_ops = {
+	.ndo_start_xmit		= ec_bhf_start_xmit,
+	.ndo_open		= ec_bhf_open,
+	.ndo_stop		= ec_bhf_stop,
+	.ndo_get_stats64	= ec_bhf_get_stats,
+	.ndo_change_mtu		= eth_change_mtu,
+	.ndo_validate_addr	= eth_validate_addr,
+	.ndo_set_mac_address	= eth_mac_addr
+};
+
+static int ec_bhf_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	int err = 0;
+	void * __iomem io;
+	void * __iomem dma_io;
+	struct net_device *net_dev;
+	struct ec_bhf_priv *priv;
+
+	err = pci_enable_device(dev);
+	if (err)
+		return err;
+
+	pci_set_master(dev);
+
+	err = pci_set_dma_mask(dev, DMA_BIT_MASK(32));
+	if (err) {
+		dev_err(&dev->dev,
+			"Required dma mask not supported, failed to initialize device\n");
+		err = -EIO;
+		goto err_disable_dev;
+	}
+
+	err = pci_set_consistent_dma_mask(dev, DMA_BIT_MASK(32));
+	if (err) {
+		dev_err(&dev->dev,
+			"Required dma mask not supported, failed to initialize device\n");
+		goto err_disable_dev;
+	}
+
+	err = pci_request_regions(dev, "ec_bhf");
+	if (err) {
+		dev_err(&dev->dev,
+			"Failed to request pci memory regions\n");
+		goto err_disable_dev;
+	}
+
+	io = pci_iomap(dev, 0, 0);
+	if (!io) {
+		dev_err(&dev->dev, "Failed to map pci card memory bar 0");
+		err = -EIO;
+		goto err_release_regions;
+	}
+
+	dma_io = pci_iomap(dev, 2, 0);
+	if (!dma_io) {
+		dev_err(&dev->dev, "Failed to map pci card memory bar 2");
+		err = -EIO;
+		goto err_unmap;
+	}
+
+	net_dev = alloc_etherdev(sizeof(struct ec_bhf_priv));
+	if (net_dev == 0) {
+		err = -ENOMEM;
+		goto err_unmap_dma_io;
+	}
+
+	pci_set_drvdata(dev, net_dev);
+	SET_NETDEV_DEV(net_dev, &dev->dev);
+
+	net_dev->features = 0;
+	net_dev->flags |= IFF_NOARP;
+
+	net_dev->netdev_ops = &ec_bhf_netdev_ops;
+
+	priv = netdev_priv(net_dev);
+	priv->net_dev = net_dev;
+	priv->io = io;
+	priv->dma_io = dma_io;
+	priv->dev = dev;
+
+	err = ec_bhf_setup_offsets(priv);
+	if (err < 0)
+		goto err_free_net_dev;
+
+	memcpy_fromio(net_dev->dev_addr, priv->mii_io + MII_MAC_ADDR, 6);
+
+	dev_info(&dev->dev, "CX5020 Ethercat master address: %pM\n",
+		 net_dev->dev_addr);
+
+	err = register_netdev(net_dev);
+	if (err < 0)
+		goto err_free_net_dev;
+
+	return 0;
+
+err_free_net_dev:
+	free_netdev(net_dev);
+err_unmap_dma_io:
+	pci_iounmap(dev, dma_io);
+err_unmap:
+	pci_iounmap(dev, io);
+err_release_regions:
+	pci_release_regions(dev);
+err_disable_dev:
+	pci_clear_master(dev);
+	pci_disable_device(dev);
+
+	return err;
+}
+
+static void ec_bhf_remove(struct pci_dev *dev)
+{
+	struct net_device *net_dev = pci_get_drvdata(dev);
+	struct ec_bhf_priv *priv = netdev_priv(net_dev);
+
+	unregister_netdev(net_dev);
+	free_netdev(net_dev);
+
+	pci_iounmap(dev, priv->dma_io);
+	pci_iounmap(dev, priv->io);
+	pci_release_regions(dev);
+	pci_clear_master(dev);
+	pci_disable_device(dev);
+}
+
+static struct pci_driver pci_driver = {
+	.name		= "ec_bhf",
+	.id_table	= ids,
+	.probe		= ec_bhf_probe,
+	.remove		= ec_bhf_remove,
+};
+
+static int __init ec_bhf_init(void)
+{
+	return pci_register_driver(&pci_driver);
+}
+
+static void __exit ec_bhf_exit(void)
+{
+	pci_unregister_driver(&pci_driver);
+}
+
+module_init(ec_bhf_init);
+module_exit(ec_bhf_exit);
+
+module_param(polling_frequency, long, S_IRUGO);
+MODULE_PARM_DESC(polling_frequency, "Polling timer frequency in ns");
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Dariusz Marcinkiewicz <[email-masked]>");
-- 
1.7.10.4