Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / ethernet / ec_bhf.c
diff --git a/kernel/drivers/net/ethernet/ec_bhf.c b/kernel/drivers/net/ethernet/ec_bhf.c
new file mode 100644 (file)
index 0000000..d101750
--- /dev/null
@@ -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>");