--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/devices/ccat/netdev.c Fri Apr 25 16:42:36 2014 +0200
@@ -0,0 +1,595 @@
+/**
+ Network Driver for Beckhoff CCAT communication controller
+ Copyright (C) 2014 Beckhoff Automation GmbH
+ Author: Patrick Bruenn <p.bruenn@beckhoff.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.
+*/
+
+#include <linux/etherdevice.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/kfifo.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/spinlock.h>
+
+#include "compat.h"
+#include "module.h"
+#include "netdev.h"
+#include "print.h"
+
+/**
+ * EtherCAT frame to enable forwarding on EtherCAT Terminals
+ */
+static const UINT8 frameForwardEthernetFrames[] = {
+ 0x01, 0x01, 0x05, 0x01, 0x00, 0x00,
+ 0x00, 0x1b, 0x21, 0x36, 0x1b, 0xce,
+ 0x88, 0xa4, 0x0e, 0x10,
+ 0x08,
+ 0x00,
+ 0x00, 0x00,
+ 0x00, 0x01,
+ 0x02, 0x00,
+ 0x00, 0x00,
+ 0x00, 0x00,
+ 0x00, 0x00
+};
+
+#define FIFO_LENGTH 64
+#define DMA_POLL_DELAY_RANGE_USECS 100, 100 /* time to sleep between rx/tx DMA polls */
+#define POLL_DELAY_RANGE_USECS 500, 1000 /* time to sleep between link state polls */
+
+static void ec_poll(struct net_device *dev);
+static int run_poll_thread(void *data);
+static int run_rx_thread(void *data);
+static int run_tx_thread(void *data);
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 35)
+static struct rtnl_link_stats64 *ccat_eth_get_stats64(struct net_device *dev, struct rtnl_link_stats64
+ *storage);
+#endif
+static int ccat_eth_open(struct net_device *dev);
+static netdev_tx_t ccat_eth_start_xmit(struct sk_buff *skb,
+ struct net_device *dev);
+static int ccat_eth_stop(struct net_device *dev);
+static void ccat_eth_xmit_raw(struct net_device *dev, const char *data,
+ size_t len);
+
+static const struct net_device_ops ccat_eth_netdev_ops = {
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 35)
+ .ndo_get_stats64 = ccat_eth_get_stats64,
+#endif
+ .ndo_open = ccat_eth_open,
+ .ndo_start_xmit = ccat_eth_start_xmit,
+ .ndo_stop = ccat_eth_stop,
+};
+
+static void ecdev_kfree_skb_any(struct sk_buff *skb)
+{
+ /* never release a skb in EtherCAT mode */
+}
+
+static void ecdev_carrier_on(struct net_device *const netdev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(netdev);
+ ecdev_set_link(priv->ecdev, 1);
+}
+
+static void ecdev_carrier_off(struct net_device *const netdev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(netdev);
+ ecdev_set_link(priv->ecdev, 0);
+}
+
+static void ecdev_nop(struct net_device *const netdev)
+{
+ /* dummy called if nothing has to be done in EtherCAT operation mode */
+}
+
+static void ecdev_tx_fifo_full(struct net_device *const dev,
+ const struct ccat_eth_frame *const frame)
+{
+ /* we are polled -> there is nothing we can do in EtherCAT mode */
+}
+
+static void unregister_ecdev(struct net_device *const netdev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(netdev);
+ ecdev_close(priv->ecdev);
+ ecdev_withdraw(priv->ecdev);
+}
+
+typedef void (*fifo_add_function) (struct ccat_eth_frame *,
+ struct ccat_eth_dma_fifo *);
+
+static void ccat_eth_rx_fifo_add(struct ccat_eth_frame *frame,
+ struct ccat_eth_dma_fifo *fifo)
+{
+ const size_t offset = ((void *)(frame) - fifo->dma.virt);
+ const uint32_t addr_and_length = (1 << 31) | offset;
+ frame->received = 0;
+ iowrite32(addr_and_length, fifo->reg);
+}
+
+static void ccat_eth_tx_fifo_add_free(struct ccat_eth_frame *frame,
+ struct ccat_eth_dma_fifo *fifo)
+{
+ /* mark frame as ready to use for tx */
+ frame->sent = 1;
+}
+
+static void ccat_eth_tx_fifo_full(struct net_device *const dev,
+ const struct ccat_eth_frame *const frame)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ netif_stop_queue(dev);
+ priv->next_tx_frame = frame;
+ wake_up_process(priv->tx_thread);
+}
+
+static void ccat_eth_dma_fifo_reset(struct ccat_eth_dma_fifo *fifo)
+{
+ struct ccat_eth_frame *frame = fifo->dma.virt;
+ const struct ccat_eth_frame *const end = frame + FIFO_LENGTH;
+
+ /* reset hw fifo */
+ iowrite32(0, fifo->reg + 0x8);
+ wmb();
+
+ if (fifo->add) {
+ while (frame < end) {
+ fifo->add(frame, fifo);
+ ++frame;
+ }
+ }
+}
+
+static int ccat_eth_dma_fifo_init(struct ccat_eth_dma_fifo *fifo,
+ void __iomem * const fifo_reg,
+ fifo_add_function add, size_t channel,
+ struct ccat_eth_priv *const priv)
+{
+ if (0 !=
+ ccat_dma_init(&fifo->dma, channel, priv->ccatdev->bar[2].ioaddr,
+ &priv->ccatdev->pdev->dev)) {
+ pr_info("init DMA%llu memory failed.\n", (uint64_t) channel);
+ return -1;
+ }
+ fifo->add = add;
+ fifo->reg = fifo_reg;
+ return 0;
+}
+
+/**
+ * Stop both (Rx/Tx) DMA fifo's and free related management structures
+ */
+static void ccat_eth_priv_free_dma(struct ccat_eth_priv *priv)
+{
+ /* reset hw fifo's */
+ iowrite32(0, priv->rx_fifo.reg + 0x8);
+ iowrite32(0, priv->tx_fifo.reg + 0x8);
+ wmb();
+
+ /* release dma */
+ ccat_dma_free(&priv->rx_fifo.dma);
+ ccat_dma_free(&priv->tx_fifo.dma);
+ pr_debug("DMA fifo's stopped.\n");
+}
+
+/**
+ * Initalizes both (Rx/Tx) DMA fifo's and related management structures
+ */
+static int ccat_eth_priv_init_dma(struct ccat_eth_priv *priv)
+{
+ if (ccat_eth_dma_fifo_init
+ (&priv->rx_fifo, priv->reg.rx_fifo, ccat_eth_rx_fifo_add,
+ priv->info.rxDmaChn, priv)) {
+ pr_warn("init Rx DMA fifo failed.\n");
+ return -1;
+ }
+
+ if (ccat_eth_dma_fifo_init
+ (&priv->tx_fifo, priv->reg.tx_fifo, ccat_eth_tx_fifo_add_free,
+ priv->info.txDmaChn, priv)) {
+ pr_warn("init Tx DMA fifo failed.\n");
+ ccat_dma_free(&priv->rx_fifo.dma);
+ return -1;
+ }
+
+ /* disable MAC filter */
+ iowrite8(0, priv->reg.mii + 0x8 + 6);
+ wmb();
+ return 0;
+}
+
+/**
+ * Initializes the CCat... members of the ccat_eth_priv structure.
+ * Call this function only if info and ioaddr are already initialized!
+ */
+static void ccat_eth_priv_init_mappings(struct ccat_eth_priv *priv)
+{
+ CCatInfoBlockOffs offsets;
+ void __iomem *const func_base =
+ priv->ccatdev->bar[0].ioaddr + priv->info.nAddr;
+ memcpy_fromio(&offsets, func_base, sizeof(offsets));
+ priv->reg.mii = func_base + offsets.nMMIOffs;
+ priv->reg.tx_fifo = func_base + offsets.nTxFifoOffs;
+ priv->reg.rx_fifo = func_base + offsets.nTxFifoOffs + 0x10;
+ priv->reg.mac = func_base + offsets.nMacRegOffs;
+ priv->reg.rx_mem = func_base + offsets.nRxMemOffs;
+ priv->reg.tx_mem = func_base + offsets.nTxMemOffs;
+ priv->reg.misc = func_base + offsets.nMiscOffs;
+}
+
+/**
+ * Read link state from CCAT hardware
+ * @return 1 if link is up, 0 if not
+ */
+inline static size_t ccat_eth_priv_read_link_state(const struct ccat_eth_priv
+ *const priv)
+{
+ return (1 << 24) == (ioread32(priv->reg.mii + 0x8 + 4) & (1 << 24));
+}
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 35)
+static struct rtnl_link_stats64 *ccat_eth_get_stats64(struct net_device *dev, struct rtnl_link_stats64
+ *storage)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ CCatMacRegs mac;
+ memcpy_fromio(&mac, priv->reg.mac, sizeof(mac));
+ storage->rx_packets = mac.rxFrameCnt; /* total packets received */
+ storage->tx_packets = mac.txFrameCnt; /* total packets transmitted */
+ storage->rx_bytes = atomic64_read(&priv->rx_bytes); /* total bytes received */
+ storage->tx_bytes = atomic64_read(&priv->tx_bytes); /* total bytes transmitted */
+ storage->rx_errors = mac.frameLenErrCnt + mac.dropFrameErrCnt + mac.crcErrCnt + mac.rxErrCnt; /* bad packets received */
+ //TODO __u64 tx_errors; /* packet transmit problems */
+ storage->rx_dropped = atomic64_read(&priv->rx_dropped); /* no space in linux buffers */
+ storage->tx_dropped = atomic64_read(&priv->tx_dropped); /* no space available in linux */
+ //TODO __u64 multicast; /* multicast packets received */
+ //TODO __u64 collisions;
+
+ /* detailed rx_errors: */
+ storage->rx_length_errors = mac.frameLenErrCnt;
+ storage->rx_over_errors = mac.dropFrameErrCnt; /* receiver ring buff overflow */
+ storage->rx_crc_errors = mac.crcErrCnt; /* recved pkt with crc error */
+ storage->rx_frame_errors = mac.rxErrCnt; /* recv'd frame alignment error */
+ storage->rx_fifo_errors = mac.dropFrameErrCnt; /* recv'r fifo overrun */
+ //TODO __u64 rx_missed_errors; /* receiver missed packet */
+
+ /* detailed tx_errors */
+ //TODO __u64 tx_aborted_errors;
+ //TODO __u64 tx_carrier_errors;
+ //TODO __u64 tx_fifo_errors;
+ //TODO __u64 tx_heartbeat_errors;
+ //TODO __u64 tx_window_errors;
+
+ /* for cslip etc */
+ //TODO __u64 rx_compressed;
+ //TODO __u64 tx_compressed;
+ return storage;
+}
+#endif
+
+struct ccat_eth_priv *ccat_eth_init(const struct ccat_device *const ccatdev,
+ const void __iomem * const addr)
+{
+ struct ccat_eth_priv *priv;
+ struct net_device *const netdev = alloc_etherdev(sizeof(*priv));
+ priv = netdev_priv(netdev);
+ priv->netdev = netdev;
+ priv->ccatdev = ccatdev;
+
+ /* ccat register mappings */
+ memcpy_fromio(&priv->info, addr, sizeof(priv->info));
+ ccat_eth_priv_init_mappings(priv);
+ ccat_print_function_info(priv);
+
+ if (ccat_eth_priv_init_dma(priv)) {
+ pr_warn("%s(): DMA initialization failed.\n", __FUNCTION__);
+ free_netdev(netdev);
+ return NULL;
+ }
+
+ /* init netdev with MAC and stack callbacks */
+ memcpy_fromio(netdev->dev_addr, priv->reg.mii + 8, 6);
+ netdev->netdev_ops = &ccat_eth_netdev_ops;
+
+ /* use as EtherCAT device? */
+ priv->ecdev = ecdev_offer(netdev, ec_poll, THIS_MODULE);
+ if (priv->ecdev) {
+ priv->carrier_off = ecdev_carrier_off;
+ priv->carrier_on = ecdev_carrier_on;
+ priv->kfree_skb_any = ecdev_kfree_skb_any;
+ priv->start_queue = ecdev_nop;
+ priv->stop_queue = ecdev_nop;
+ priv->tx_fifo_full = ecdev_tx_fifo_full;
+ priv->unregister = unregister_ecdev;
+ if (ecdev_open(priv->ecdev)) {
+ pr_info("unable to register network device.\n");
+ ecdev_withdraw(priv->ecdev);
+ ccat_eth_priv_free_dma(priv);
+ free_netdev(netdev);
+ return NULL;
+ }
+ return priv;
+ }
+
+ /* EtherCAT disabled -> prepare normal ethernet mode */
+ priv->carrier_off = netif_carrier_off;
+ priv->carrier_on = netif_carrier_on;
+ priv->kfree_skb_any = dev_kfree_skb_any;
+ priv->start_queue = netif_start_queue;
+ priv->stop_queue = netif_stop_queue;
+ priv->tx_fifo_full = ccat_eth_tx_fifo_full;
+ priv->unregister = unregister_netdev;
+ if (register_netdev(netdev)) {
+ pr_info("unable to register network device.\n");
+ ccat_eth_priv_free_dma(priv);
+ free_netdev(netdev);
+ return NULL;
+ }
+ pr_info("registered %s as network device.\n", netdev->name);
+ priv->rx_thread = kthread_run(run_rx_thread, netdev, "%s_rx", DRV_NAME);
+ priv->tx_thread = kthread_run(run_tx_thread, netdev, "%s_tx", DRV_NAME);
+ return priv;
+}
+
+void ccat_eth_remove(struct ccat_eth_priv *const priv)
+{
+ if (priv->rx_thread) {
+ kthread_stop(priv->rx_thread);
+ }
+ if (priv->tx_thread) {
+ kthread_stop(priv->tx_thread);
+ }
+ priv->unregister(priv->netdev);
+ ccat_eth_priv_free_dma(priv);
+ free_netdev(priv->netdev);
+ pr_debug("%s(): done\n", __FUNCTION__);
+}
+
+static int ccat_eth_open(struct net_device *dev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ priv->carrier_off(dev);
+ priv->poll_thread =
+ kthread_run(run_poll_thread, dev, "%s_poll", DRV_NAME);
+
+ //TODO
+ return 0;
+}
+
+static const size_t CCATRXDESC_HEADER_LEN = 20;
+static void ccat_eth_receive(struct net_device *const dev,
+ const struct ccat_eth_frame *const frame)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ const size_t len = frame->length - CCATRXDESC_HEADER_LEN;
+ struct sk_buff *skb = dev_alloc_skb(len + NET_IP_ALIGN);
+ if (!skb) {
+ pr_info("%s() out of memory :-(\n", __FUNCTION__);
+ atomic64_inc(&priv->rx_dropped);
+ return;
+ }
+ skb->dev = dev;
+ skb_reserve(skb, NET_IP_ALIGN);
+ skb_copy_to_linear_data(skb, frame->data, len);
+ skb_put(skb, len);
+ skb->protocol = eth_type_trans(skb, dev);
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ atomic64_add(len, &priv->rx_bytes);
+ netif_rx(skb);
+}
+
+/**
+ * Rx handler in EtherCAT operation mode
+ * priv->ecdev should always be valid!
+ */
+static void ec_poll(struct net_device *dev)
+{
+ static size_t next = 0;
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ struct ccat_eth_frame *frame =
+ ((struct ccat_eth_frame *)priv->rx_fifo.dma.virt) + next;
+ if (frame->received) {
+ ecdev_receive(priv->ecdev, frame->data,
+ frame->length - CCATRXDESC_HEADER_LEN);
+ frame->received = 0;
+ ccat_eth_rx_fifo_add(frame, &priv->rx_fifo);
+ next = (next + 1) % FIFO_LENGTH;
+ } else {
+ //TODO dev_warn(&dev->dev, "%s(): frame was not ready\n", __FUNCTION__);
+ }
+}
+
+static netdev_tx_t ccat_eth_start_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ static size_t next = 0;
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ struct ccat_eth_frame *const frame =
+ ((struct ccat_eth_frame *)priv->tx_fifo.dma.virt);
+ uint32_t addr_and_length;
+
+ if (skb_is_nonlinear(skb)) {
+ pr_warn("Non linear skb not supported -> drop frame.\n");
+ atomic64_inc(&priv->tx_dropped);
+ priv->kfree_skb_any(skb);
+ return NETDEV_TX_OK;
+ }
+
+ if (skb->len > sizeof(frame->data)) {
+ pr_warn("skb.len %llu exceeds dma buffer %llu -> drop frame.\n",
+ (uint64_t) skb->len, (uint64_t) sizeof(frame->data));
+ atomic64_inc(&priv->tx_dropped);
+ priv->kfree_skb_any(skb);
+ return NETDEV_TX_OK;
+ }
+
+ if (!frame[next].sent) {
+ netdev_err(dev, "BUG! Tx Ring full when queue awake!\n");
+ ccat_eth_tx_fifo_full(dev, &frame[next]);
+ return NETDEV_TX_BUSY;
+ }
+
+ /* prepare frame in DMA memory */
+ frame[next].sent = 0;
+ frame[next].length = skb->len;
+ memcpy(frame[next].data, skb->data, skb->len);
+
+ priv->kfree_skb_any(skb);
+
+ addr_and_length = 8 + (next * sizeof(*frame));
+ addr_and_length +=
+ ((frame[next].length + CCAT_DMA_FRAME_HEADER_LENGTH) / 8) << 24;
+ iowrite32(addr_and_length, priv->reg.tx_fifo); /* add to DMA fifo */
+ atomic64_add(frame[next].length, &priv->tx_bytes); /* update stats */
+
+ next = (next + 1) % FIFO_LENGTH;
+ /* stop queue if tx ring is full */
+ if (!frame[next].sent) {
+ ccat_eth_tx_fifo_full(dev, &frame[next]);
+ }
+ return NETDEV_TX_OK;
+}
+
+static int ccat_eth_stop(struct net_device *dev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ priv->stop_queue(dev);
+ if (priv->poll_thread) {
+ /* TODO care about smp context? */
+ kthread_stop(priv->poll_thread);
+ priv->poll_thread = NULL;
+ }
+ netdev_info(dev, "stopped.\n");
+ return 0;
+}
+
+static void ccat_eth_link_down(struct net_device *dev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ priv->stop_queue(dev);
+ priv->carrier_off(dev);
+ netdev_info(dev, "NIC Link is Down\n");
+}
+
+static void ccat_eth_link_up(struct net_device *const dev)
+{
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ netdev_info(dev, "NIC Link is Up\n");
+ /* TODO netdev_info(dev, "NIC Link is Up %u Mbps %s Duplex\n",
+ speed == SPEED_100 ? 100 : 10,
+ cmd.duplex == DUPLEX_FULL ? "Full" : "Half"); */
+
+ ccat_eth_dma_fifo_reset(&priv->rx_fifo);
+ ccat_eth_dma_fifo_reset(&priv->tx_fifo);
+ ccat_eth_xmit_raw(dev, frameForwardEthernetFrames,
+ sizeof(frameForwardEthernetFrames));
+ priv->carrier_on(dev);
+ priv->start_queue(dev);
+}
+
+/**
+ * Function to transmit a raw buffer to the network (f.e. frameForwardEthernetFrames)
+ * @dev a valid net_device
+ * @data pointer to your raw buffer
+ * @len number of bytes in the raw buffer to transmit
+ */
+static void ccat_eth_xmit_raw(struct net_device *dev, const char *const data,
+ size_t len)
+{
+ struct sk_buff *skb = dev_alloc_skb(len);
+ skb->dev = dev;
+ skb_copy_to_linear_data(skb, data, len);
+ skb_put(skb, len);
+ ccat_eth_start_xmit(skb, dev);
+}
+
+/**
+ * Since CCAT doesn't support interrupts until now, we have to poll
+ * some status bits to recognize things like link change etc.
+ */
+static int run_poll_thread(void *data)
+{
+ struct net_device *const dev = (struct net_device *)data;
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ size_t link = 0;
+
+ while (!kthread_should_stop()) {
+ if (ccat_eth_priv_read_link_state(priv) != link) {
+ link = !link;
+ link ? ccat_eth_link_up(dev) : ccat_eth_link_down(dev);
+ }
+ usleep_range(POLL_DELAY_RANGE_USECS);
+ }
+ pr_debug("%s() stopped.\n", __FUNCTION__);
+ return 0;
+}
+
+static int run_rx_thread(void *data)
+{
+ struct net_device *const dev = (struct net_device *)data;
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+ struct ccat_eth_frame *frame = priv->rx_fifo.dma.virt;
+ const struct ccat_eth_frame *const end = frame + FIFO_LENGTH;
+
+ while (!kthread_should_stop()) {
+ /* wait until frame was used by DMA for Rx */
+ while (!kthread_should_stop() && !frame->received) {
+ usleep_range(DMA_POLL_DELAY_RANGE_USECS);
+ }
+
+ /* can be NULL, if we are asked to stop! */
+ if (frame->received) {
+ ccat_eth_receive(dev, frame);
+ frame->received = 0;
+ ccat_eth_rx_fifo_add(frame, &priv->rx_fifo);
+ }
+ if (++frame >= end) {
+ frame = priv->rx_fifo.dma.virt;
+ }
+ }
+ pr_debug("%s() stopped.\n", __FUNCTION__);
+ return 0;
+}
+
+/**
+ * Polling of tx dma descriptors in ethernet operating mode
+ */
+static int run_tx_thread(void *data)
+{
+ struct net_device *const dev = (struct net_device *)data;
+ struct ccat_eth_priv *const priv = netdev_priv(dev);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ while (!kthread_should_stop()) {
+ const struct ccat_eth_frame *const frame = priv->next_tx_frame;
+ if (frame) {
+ while (!kthread_should_stop() && !frame->sent) {
+ usleep_range(DMA_POLL_DELAY_RANGE_USECS);
+ }
+ }
+ netif_wake_queue(dev);
+ schedule();
+ set_current_state(TASK_INTERRUPTIBLE);
+ }
+ set_current_state(TASK_RUNNING);
+ pr_debug("%s() stopped.\n", __FUNCTION__);
+ return 0;
+}