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Release 4.11 drivers/net/ethernet/ec_bhf.c

/*
 * drivers/net/ethernet/ec_bhf.c
 *
 * Copyright (C) 2014 Darek Marcinkiewicz <reksio@newterm.pl>
 *
 * 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.
 */

#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


#define DMA_WINDOW_SIZE_MASK	0xfffffffc


#define ETHERCAT_MASTER_ID	0x14


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)


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); }

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Darek Marcinkiewicz121100.00%1100.00%
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static void ec_bhf_send_packet(struct ec_bhf_priv *priv, struct tx_desc *desc) { u32 len = le16_to_cpu(desc->header.len) + sizeof(desc->header); u32 addr = (u8 *)desc - priv->tx_buf.buf; iowrite32((ALIGN(len, 8) << 24) | addr, priv->fifo_io + FIFO_TX_REG); }

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static int ec_bhf_desc_sent(struct tx_desc *desc) { return le32_to_cpu(desc->header.sent) & TX_HDR_SENT; }

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static void ec_bhf_process_tx(struct ec_bhf_priv *priv) { if (unlikely(netif_queue_stopped(priv->net_dev))) { /* Make sure that we perceive changes to tx_dnext. */ smp_rmb(); if (ec_bhf_desc_sent(&priv->tx_descs[priv->tx_dnext])) netif_wake_queue(priv->net_dev); } }

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static int ec_bhf_pkt_received(struct rx_desc *desc) { return le32_to_cpu(desc->header.recv) & RXHDR_NEXT_RECV_FLAG; }

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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); }

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Darek Marcinkiewicz43100.00%1100.00%
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static void ec_bhf_process_rx(struct ec_bhf_priv *priv) { struct rx_desc *desc = &priv->rx_descs[priv->rx_dnext]; 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); if (skb) { memcpy(skb_put(skb, pkt_size), data, pkt_size); skb->protocol = eth_type_trans(skb, priv->net_dev); priv->stat_rx_bytes += pkt_size; netif_rx(skb); } else { dev_err_ratelimited(PRIV_TO_DEV(priv), "Couldn't allocate a skb_buff for a packet of size %u\n", 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]; } }

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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, polling_frequency); return HRTIMER_RESTART; }

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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; block_count = ioread8(priv->io + INFO_BLOCK_BLK_CNT); 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; } ec_info = priv->io + i * INFO_BLOCK_SIZE; priv->tx_dma_chan = ioread8(ec_info + INFO_BLOCK_TX_CHAN); priv->rx_dma_chan = ioread8(ec_info + INFO_BLOCK_RX_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); return 0; }

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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; 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])) { /* Make sure that updates to tx_dnext are perceived * by timer routine. */ smp_wmb(); netif_stop_queue(net_dev); } priv->stat_tx_bytes += len; dev_kfree_skb(skb); return NETDEV_TX_OK; }

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Darek Marcinkiewicz161100.00%2100.00%
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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 &= DMA_WINDOW_SIZE_MASK; /* 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; buf->alloc = dma_alloc_coherent(dev, buf->alloc_len, &buf->alloc_phys, GFP_KERNEL); if (buf->alloc == NULL) { dev_err(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); return 0; }

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Darek Marcinkiewicz201100.00%2100.00%
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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); }

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Darek Marcinkiewicz84100.00%1100.00%
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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); } }

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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; 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\n"); goto out; } ec_bhf_setup_rx_descs(priv); 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\n"); goto error_rx_free; } 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, polling_frequency, HRTIMER_MODE_REL); 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; }

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Darek Marcinkiewicz212100.00%1100.00%
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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; }

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Darek Marcinkiewicz98100.00%1100.00%
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static void ec_bhf_get_stats(struct net_device *net_dev, struct rtnl_link_stats64 *stats) { struct ec_bhf_priv *priv = netdev_priv(net_dev); 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; }

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Darek Marcinkiewicz11199.11%150.00%
Stephen Hemminger10.89%150.00%
Total112100.00%2100.00%

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_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) { struct net_device *net_dev; struct ec_bhf_priv *priv; void __iomem *dma_io; void __iomem *io; int err = 0; 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 == NULL) { 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); 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; }

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Darek Marcinkiewicz419100.00%2100.00%
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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); }

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Darek Marcinkiewicz74100.00%1100.00%
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static struct pci_driver pci_driver = { .name = "ec_bhf", .id_table = ids, .probe = ec_bhf_probe, .remove = ec_bhf_remove, }; module_pci_driver(pci_driver); module_param(polling_frequency, long, S_IRUGO); MODULE_PARM_DESC(polling_frequency, "Polling timer frequency in ns"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Dariusz Marcinkiewicz <reksio@newterm.pl>");

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Darek Marcinkiewicz282199.89%360.00%
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Stephen Hemminger10.04%120.00%
Total2824100.00%5100.00%
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