diff options
Diffstat (limited to 'kernel/drivers/net/ethernet/ec_bhf.c')
| -rw-r--r-- | kernel/drivers/net/ethernet/ec_bhf.c | 625 |
1 files changed, 625 insertions, 0 deletions
diff --git a/kernel/drivers/net/ethernet/ec_bhf.c b/kernel/drivers/net/ethernet/ec_bhf.c new file mode 100644 index 000000000..d1017509b --- /dev/null +++ b/kernel/drivers/net/ethernet/ec_bhf.c @@ -0,0 +1,625 @@ + /* + * 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); +} + +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); +} + +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))) { + /* 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); + } +} + +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]; + + 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]; + } +} + +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; + + 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; +} + +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; +} + +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; +} + +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; + + 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, ktime_set(0, 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; +} + +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); + + 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) +{ + 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; +} + +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 <reksio@newterm.pl>"); |