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/******************************************************************************

     2

 *

     3

 *  $Id$

     4

 *

     5

 *  Copyright (C) 2006-2008  Florian Pose, Ingenieurgemeinschaft IgH

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 *

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 *  This file is part of the IgH EtherCAT Master.

     8

 *

     9

 *  The IgH EtherCAT Master is free software; you can redistribute it and/or

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 *  modify it under the terms of the GNU General Public License version 2, as

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 *  published by the Free Software Foundation.

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 *

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 *  The IgH EtherCAT Master is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General

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 *  Public License for more details.

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 *

    18

 *  You should have received a copy of the GNU General Public License along

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 *  with the IgH EtherCAT Master; if not, write to the Free Software

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 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

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 *

    22

 *  ---

    23

 *

    24

 *  The license mentioned above concerns the source code only. Using the

    25

 *  EtherCAT technology and brand is only permitted in compliance with the

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 *  industrial property and similar rights of Beckhoff Automation GmbH.

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 *

    28

 *****************************************************************************/

    29

    30

/**

    31

   \file

    32

   Ethernet over EtherCAT (EoE).

    33

*/

    34

    35

/*****************************************************************************/

    36

    37

#include <linux/version.h>

    38

#include <linux/netdevice.h>

    39

#include <linux/etherdevice.h>

    40

    41

#include "globals.h"

    42

#include "master.h"

    43

#include "slave.h"

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#include "mailbox.h"

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#include "ethernet.h"

    46

    47

/*****************************************************************************/

    48

    49

/** Defines the debug level of EoE processing.

    50

 *

    51

 * 0 = No debug messages.

    52

 * 1 = Output warnings.

    53

 * 2 = Output actions.

    54

 * 3 = Output actions and frame data.

    55

 */

    56

#define EOE_DEBUG_LEVEL 1

    57

    58

/** Size of the EoE tx queue.

    59

 */

    60

#define EC_EOE_TX_QUEUE_SIZE 100

    61

    62

/** Number of tries.

    63

 */

    64

#define EC_EOE_TRIES 100

    65

    66

/*****************************************************************************/

    67

    68

void ec_eoe_flush(ec_eoe_t *);

    69

    70

// state functions

    71

void ec_eoe_state_rx_start(ec_eoe_t *);

    72

void ec_eoe_state_rx_check(ec_eoe_t *);

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void ec_eoe_state_rx_fetch(ec_eoe_t *);

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void ec_eoe_state_tx_start(ec_eoe_t *);

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void ec_eoe_state_tx_sent(ec_eoe_t *);

    76

    77

// net_device functions

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int ec_eoedev_open(struct net_device *);

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int ec_eoedev_stop(struct net_device *);

    80

int ec_eoedev_tx(struct sk_buff *, struct net_device *);

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struct net_device_stats *ec_eoedev_stats(struct net_device *);

    82

    83

/*****************************************************************************/

    84

    85

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)

    86

/** Device operations for EoE interfaces.

    87

 */

    88

static const struct net_device_ops ec_eoedev_ops = {

    89

    .ndo_open = ec_eoedev_open,

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    .ndo_stop = ec_eoedev_stop,

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    .ndo_start_xmit = ec_eoedev_tx,

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    .ndo_get_stats = ec_eoedev_stats,

    93

};

    94

#endif

    95

    96

/*****************************************************************************/

    97

    98

/** EoE constructor.

    99

 *

   100

 * Initializes the EoE handler, creates a net_device and registers it.

   101

 *

   102

 * \return Zero on success, otherwise a negative error code.

   103

 */

   104

int ec_eoe_init(

   105

        ec_eoe_t *eoe, /**< EoE handler */

   106

        ec_slave_t *slave /**< EtherCAT slave */

   107

        )

   108

{

   109

    ec_eoe_t **priv;

   110

    int i, ret = 0;

   111

    char name[EC_DATAGRAM_NAME_SIZE];

   112

   113

    eoe->slave = slave;

   114

   115

    ec_datagram_init(&eoe->datagram);

   116

    eoe->queue_datagram = 0;

   117

    eoe->state = ec_eoe_state_rx_start;

   118

    eoe->opened = 0;

   119

    eoe->rx_skb = NULL;

   120

    eoe->rx_expected_fragment = 0;

   121

    INIT_LIST_HEAD(&eoe->tx_queue);

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    eoe->tx_frame = NULL;

   123

    eoe->tx_queue_active = 0;

   124

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   125

    eoe->tx_queued_frames = 0;

   126

   127

    sema_init(&eoe->tx_queue_sem, 1);

   128

    eoe->tx_frame_number = 0xFF;

   129

    memset(&eoe->stats, 0, sizeof(struct net_device_stats));

   130

   131

    eoe->rx_counter = 0;

   132

    eoe->tx_counter = 0;

   133

    eoe->rx_rate = 0;

   134

    eoe->tx_rate = 0;

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    eoe->rate_jiffies = 0;

   136

    eoe->rx_idle = 1;

   137

    eoe->tx_idle = 1;

   138

   139

    /* device name eoe<MASTER>[as]<SLAVE>, because networking scripts don't

   140

     * like hyphens etc. in interface names. */

   141

    if (slave->effective_alias) {

   142

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

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                "eoe%ua%u", slave->master->index, slave->effective_alias);

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    } else {

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        snprintf(name, EC_DATAGRAM_NAME_SIZE,

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                "eoe%us%u", slave->master->index, slave->ring_position);

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    }

   148

   149

    snprintf(eoe->datagram.name, EC_DATAGRAM_NAME_SIZE, name);

   150

   151

#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)

   152

    eoe->dev = alloc_netdev(sizeof(ec_eoe_t *), name, NET_NAME_UNKNOWN,

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            ether_setup);

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#else

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    eoe->dev = alloc_netdev(sizeof(ec_eoe_t *), name, ether_setup);

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#endif

   157

    if (!eoe->dev) {

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        EC_SLAVE_ERR(slave, "Unable to allocate net_device %s"

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                " for EoE handler!\n", name);

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        ret = -ENODEV;

   161

        goto out_return;

   162

    }

   163

   164

    // initialize net_device

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#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)

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    eoe->dev->netdev_ops = &ec_eoedev_ops;

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#else

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    eoe->dev->open = ec_eoedev_open;

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    eoe->dev->stop = ec_eoedev_stop;

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    eoe->dev->hard_start_xmit = ec_eoedev_tx;

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    eoe->dev->get_stats = ec_eoedev_stats;

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#endif

   173

   174

    for (i = 0; i < ETH_ALEN; i++)

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        eoe->dev->dev_addr[i] = i | (i << 4);

   176

   177

    // initialize private data

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    priv = netdev_priv(eoe->dev);

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    *priv = eoe;

   180

   181

    // Usually setting the MTU appropriately makes the upper layers

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    // do the frame fragmenting. In some cases this doesn't work

   183

    // so the MTU is left on the Ethernet standard value and fragmenting

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    // is done "manually".

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#if 0

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    eoe->dev->mtu = slave->configured_rx_mailbox_size - ETH_HLEN - 10;

   187

#endif

   188

   189

    // connect the net_device to the kernel

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    ret = register_netdev(eoe->dev);

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    if (ret) {

   192

        EC_SLAVE_ERR(slave, "Unable to register net_device:"

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                " error %i\n", ret);

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        goto out_free;

   195

    }

   196

   197

    // make the last address octet unique

   198

    eoe->dev->dev_addr[ETH_ALEN - 1] = (uint8_t) eoe->dev->ifindex;

   199

    return 0;

   200

   201

 out_free:

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    free_netdev(eoe->dev);

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    eoe->dev = NULL;

   204

 out_return:

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    return ret;

   206

}

   207

   208

/*****************************************************************************/

   209

   210

/** EoE destructor.

   211

 *

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 * Unregisteres the net_device and frees allocated memory.

   213

 */

   214

void ec_eoe_clear(ec_eoe_t *eoe /**< EoE handler */)

   215

{

   216

    unregister_netdev(eoe->dev); // possibly calls close callback

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   218

    // empty transmit queue

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    ec_eoe_flush(eoe);

   220

   221

    if (eoe->tx_frame) {

   222

        dev_kfree_skb(eoe->tx_frame->skb);

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        kfree(eoe->tx_frame);

   224

    }

   225

   226

    if (eoe->rx_skb)

   227

        dev_kfree_skb(eoe->rx_skb);

   228

   229

    free_netdev(eoe->dev);

   230

   231

    ec_datagram_clear(&eoe->datagram);

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}

   233

   234

/*****************************************************************************/

   235

   236

/** Empties the transmit queue.

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 */

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void ec_eoe_flush(ec_eoe_t *eoe /**< EoE handler */)

   239

{

   240

    ec_eoe_frame_t *frame, *next;

   241

   242

    down(&eoe->tx_queue_sem);

   243

   244

    list_for_each_entry_safe(frame, next, &eoe->tx_queue, queue) {

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        list_del(&frame->queue);

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        dev_kfree_skb(frame->skb);

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        kfree(frame);

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    }

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    eoe->tx_queued_frames = 0;

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   251

    up(&eoe->tx_queue_sem);

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}

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   254

/*****************************************************************************/

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   256

/** Sends a frame or the next fragment.

   257

 *

   258

 * \return Zero on success, otherwise a negative error code.

   259

 */

   260

int ec_eoe_send(ec_eoe_t *eoe /**< EoE handler */)

   261

{

   262

    size_t remaining_size, current_size, complete_offset;

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    unsigned int last_fragment;

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    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

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    unsigned int i;

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#endif

   268

   269

    remaining_size = eoe->tx_frame->skb->len - eoe->tx_offset;

   270

   271

    if (remaining_size <= eoe->slave->configured_tx_mailbox_size - 10) {

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        current_size = remaining_size;

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        last_fragment = 1;

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    } else {

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        current_size = ((eoe->slave->configured_tx_mailbox_size - 10) / 32) * 32;

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        last_fragment = 0;

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    }

   278

   279

    if (eoe->tx_fragment_number) {

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        complete_offset = eoe->tx_offset / 32;

   281

    }

   282

    else {

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        // complete size in 32 bit blocks, rounded up.

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        complete_offset = remaining_size / 32 + 1;

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    }

   286

   287

#if EOE_DEBUG_LEVEL >= 2

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    EC_SLAVE_DBG(slave, 0, "EoE %s TX sending fragment %u%s"

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            " with %u octets (%u). %u frames queued.\n",

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            eoe->dev->name, eoe->tx_fragment_number,

   291

            last_fragment ? "" : "+", current_size, complete_offset,

   292

            eoe->tx_queued_frames);

   293

#endif

   294

   295

#if EOE_DEBUG_LEVEL >= 3

   296

    EC_SLAVE_DBG(master, 0, "");

   297

    for (i = 0; i < current_size; i++) {

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        printk("%02X ", eoe->tx_frame->skb->data[eoe->tx_offset + i]);

   299

        if ((i + 1) % 16 == 0) {

   300

            printk("\n");

   301

            EC_SLAVE_DBG(master, 0, "");

   302

        }

   303

    }

   304

    printk("\n");

   305

#endif

   306

   307

    data = ec_slave_mbox_prepare_send(eoe->slave, &eoe->datagram,

   308

            0x02, current_size + 4);

   309

    if (IS_ERR(data))

   310

        return PTR_ERR(data);

   311

   312

    EC_WRITE_U8 (data,     0x00); // eoe fragment req.

   313

    EC_WRITE_U8 (data + 1, last_fragment);

   314

    EC_WRITE_U16(data + 2, ((eoe->tx_fragment_number & 0x3F) |

   315

                            (complete_offset & 0x3F) << 6 |

   316

                            (eoe->tx_frame_number & 0x0F) << 12));

   317

   318

    memcpy(data + 4, eoe->tx_frame->skb->data + eoe->tx_offset, current_size);

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    eoe->queue_datagram = 1;

   320

   321

    eoe->tx_offset += current_size;

   322

    eoe->tx_fragment_number++;

   323

    return 0;

   324

}

   325

   326

/*****************************************************************************/

   327

   328

/** Runs the EoE state machine.

   329

 */

   330

void ec_eoe_run(ec_eoe_t *eoe /**< EoE handler */)

   331

{

   332

    if (!eoe->opened)

   333

        return;

   334

   335

    // if the datagram was not sent, or is not yet received, skip this cycle

   336

    if (eoe->queue_datagram || eoe->datagram.state == EC_DATAGRAM_SENT)

   337

        return;

   338

   339

    // call state function

   340

    eoe->state(eoe);

   341

   342

    // update statistics

   343

    if (jiffies - eoe->rate_jiffies > HZ) {

   344

        eoe->rx_rate = eoe->rx_counter;

   345

        eoe->tx_rate = eoe->tx_counter;

   346

        eoe->rx_counter = 0;

   347

        eoe->tx_counter = 0;

   348

        eoe->rate_jiffies = jiffies;

   349

    }

   350

   351

    ec_datagram_output_stats(&eoe->datagram);

   352

}

   353

   354

/*****************************************************************************/

   355

   356

/** Queues the datagram, if necessary.

   357

 */

   358

void ec_eoe_queue(ec_eoe_t *eoe /**< EoE handler */)

   359

{

   360

   if (eoe->queue_datagram) {

   361

       ec_master_queue_datagram_ext(eoe->slave->master, &eoe->datagram);

   362

       eoe->queue_datagram = 0;

   363

   }

   364

}

   365

   366

/*****************************************************************************/

   367

   368

/** Returns the state of the device.

   369

 *

   370

 * \return 1 if the device is "up", 0 if it is "down"

   371

 */

   372

int ec_eoe_is_open(const ec_eoe_t *eoe /**< EoE handler */)

   373

{

   374

    return eoe->opened;

   375

}

   376

   377

/*****************************************************************************/

   378

   379

/** Returns the idle state.

   380

 *

   381

 * \retval 1 The device is idle.

   382

 * \retval 0 The device is busy.

   383

 */

   384

int ec_eoe_is_idle(const ec_eoe_t *eoe /**< EoE handler */)

   385

{

   386

    return eoe->rx_idle && eoe->tx_idle;

   387

}

   388

   389

/******************************************************************************

   390

 *  STATE PROCESSING FUNCTIONS

   391

 *****************************************************************************/

   392

   393

/** State: RX_START.

   394

 *

   395

 * Starts a new receiving sequence by queueing a datagram that checks the

   396

 * slave's mailbox for a new EoE datagram.

   397

 *

   398

 * \todo Use both devices.

   399

 */

   400

void ec_eoe_state_rx_start(ec_eoe_t *eoe /**< EoE handler */)

   401

{

   402

    if (eoe->slave->error_flag ||

   403

            !eoe->slave->master->devices[EC_DEVICE_MAIN].link_state) {

   404

        eoe->rx_idle = 1;

   405

        eoe->tx_idle = 1;

   406

        return;

   407

    }

   408

   409

    ec_slave_mbox_prepare_check(eoe->slave, &eoe->datagram);

   410

    eoe->queue_datagram = 1;

   411

    eoe->state = ec_eoe_state_rx_check;

   412

}

   413

   414

/*****************************************************************************/

   415

   416

/** State: RX_CHECK.

   417

 *

   418

 * Processes the checking datagram sent in RX_START and issues a receive

   419

 * datagram, if new data is available.

   420

 */

   421

void ec_eoe_state_rx_check(ec_eoe_t *eoe /**< EoE handler */)

   422

{

   423

    if (eoe->datagram.state != EC_DATAGRAM_RECEIVED) {

   424

        eoe->stats.rx_errors++;

   425

#if EOE_DEBUG_LEVEL >= 1

   426

        EC_SLAVE_WARN(eoe->slave, "Failed to receive mbox"

   427

                " check datagram for %s.\n", eoe->dev->name);

   428

#endif

   429

        eoe->state = ec_eoe_state_tx_start;

   430

        return;

   431

    }

   432

   433

    if (!ec_slave_mbox_check(&eoe->datagram)) {

   434

        eoe->rx_idle = 1;

   435

        eoe->state = ec_eoe_state_tx_start;

   436

        return;

   437

    }

   438

   439

    eoe->rx_idle = 0;

   440

    ec_slave_mbox_prepare_fetch(eoe->slave, &eoe->datagram);

   441

    eoe->queue_datagram = 1;

   442

    eoe->state = ec_eoe_state_rx_fetch;

   443

}

   444

   445

/*****************************************************************************/

   446

   447

/** State: RX_FETCH.

   448

 *

   449

 * Checks if the requested data of RX_CHECK was received and processes the EoE

   450

 * datagram.

   451

 */

   452

void ec_eoe_state_rx_fetch(ec_eoe_t *eoe /**< EoE handler */)

   453

{

   454

    size_t rec_size, data_size;

   455

    uint8_t *data, frame_type, last_fragment, time_appended, mbox_prot;

   456

    uint8_t fragment_offset, fragment_number;

   457

#if EOE_DEBUG_LEVEL >= 2

   458

    uint8_t frame_number;

   459

#endif

   460

    off_t offset;

   461

#if EOE_DEBUG_LEVEL >= 3

   462

    unsigned int i;

   463

#endif

   464

   465

    if (eoe->datagram.state != EC_DATAGRAM_RECEIVED) {

   466

        eoe->stats.rx_errors++;

   467

#if EOE_DEBUG_LEVEL >= 1

   468

        EC_SLAVE_WARN(eoe->slave, "Failed to receive mbox"

   469

                " fetch datagram for %s.\n", eoe->dev->name);

   470

#endif

   471

        eoe->state = ec_eoe_state_tx_start;

   472

        return;

   473

    }

   474

   475

    data = ec_slave_mbox_fetch(eoe->slave, &eoe->datagram,

   476

            &mbox_prot, &rec_size);

   477

    if (IS_ERR(data)) {

   478

        eoe->stats.rx_errors++;

   479

#if EOE_DEBUG_LEVEL >= 1

   480

        EC_SLAVE_WARN(eoe->slave, "Invalid mailbox response for %s.\n",

   481

                eoe->dev->name);

   482

#endif

   483

        eoe->state = ec_eoe_state_tx_start;

   484

        return;

   485