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

     2

 *

     3

 *  $Id$

     4

 *

     5

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

     6

 *

     7

 *  This file is part of the IgH EtherCAT Master.

     8

 *

     9

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

    10

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

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 *  published by the Free Software Foundation.

    12

 *

    13

 *  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

    15

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

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 *  Public License for more details.

    17

 *

    18

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

    19

 *  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

    21

 *

    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.

    27

 *

    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"

    44

#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 *);

    73

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

    78

int ec_eoedev_open(struct net_device *);

    79

int ec_eoedev_stop(struct net_device *);

    80

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

    81

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,

    92

    .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

int ec_eoe_init(

   103

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

   104

        ec_slave_t *slave /**< EtherCAT slave */

   105

        )

   106

{

   107

    ec_eoe_t **priv;

   108

    int i, ret = 0;

   109

    char name[EC_DATAGRAM_NAME_SIZE];

   110

   111

    eoe->slave = slave;

   112

   113

    ec_datagram_init(&eoe->datagram);

   114

    eoe->queue_datagram = 0;

   115

    eoe->state = ec_eoe_state_rx_start;

   116

    eoe->opened = 0;

   117

    eoe->rx_skb = NULL;

   118

    eoe->rx_expected_fragment = 0;

   119

    INIT_LIST_HEAD(&eoe->tx_queue);

   120

    eoe->tx_frame = NULL;

   121

    eoe->tx_queue_active = 0;

   122

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   123

    eoe->tx_queued_frames = 0;

   124

   125

    sema_init(&eoe->tx_queue_sem, 1);

   126

    eoe->tx_frame_number = 0xFF;

   127

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

   128

   129

    eoe->rx_counter = 0;

   130

    eoe->tx_counter = 0;

   131

    eoe->rx_rate = 0;

   132

    eoe->tx_rate = 0;

   133

    eoe->rate_jiffies = 0;

   134

    eoe->rx_idle = 1;

   135

    eoe->tx_idle = 1;

   136

   137

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

   138

     * like hyphens etc. in interface names. */

   139

    if (slave->effective_alias) {

   140

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   141

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

   142

    } else {

   143

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   144

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

   145

    }

   146

   147

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

   148

   149

    if (!(eoe->dev = alloc_netdev(sizeof(ec_eoe_t *), name, ether_setup))) {

   150

        EC_ERR("Unable to allocate net_device %s for EoE handler!\n", name);

   151

        ret = -ENODEV;

   152

        goto out_return;

   153

    }

   154

   155

    // initialize net_device

   156

#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;

   161

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   162

    eoe->dev->get_stats = ec_eoedev_stats;

   163

#endif

   164

   165

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

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

   167

   168

    // initialize private data

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    priv = netdev_priv(eoe->dev);

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    *priv = eoe;

   171

   172

    // Usually setting the MTU appropriately makes the upper layers

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

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

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    // is done "manually".

   176

#if 0

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

   178

#endif

   179

   180

    // connect the net_device to the kernel

   181

    ret = register_netdev(eoe->dev);

   182

    if (ret) {

   183

        EC_ERR("Unable to register net_device: error %i\n", ret);

   184

        goto out_free;

   185

    }

   186

   187

    // make the last address octet unique

   188

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

   189

    return 0;

   190

   191

 out_free:

   192

    free_netdev(eoe->dev);

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    eoe->dev = NULL;

   194

 out_return:

   195

    return ret;

   196

}

   197

   198

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

   199

   200

/** EoE destructor.

   201

 *

   202

 * Unregisteres the net_device and frees allocated memory.

   203

 */

   204

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

   205

{

   206

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

   207

   208

    // empty transmit queue

   209

    ec_eoe_flush(eoe);

   210

   211

    if (eoe->tx_frame) {

   212

        dev_kfree_skb(eoe->tx_frame->skb);

   213

        kfree(eoe->tx_frame);

   214

    }

   215

   216

    if (eoe->rx_skb)

   217

        dev_kfree_skb(eoe->rx_skb);

   218

   219

    free_netdev(eoe->dev);

   220

   221

    ec_datagram_clear(&eoe->datagram);

   222

}

   223

   224

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

   225

   226

/** Empties the transmit queue.

   227

 */

   228

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

   229

{

   230

    ec_eoe_frame_t *frame, *next;

   231

   232

    down(&eoe->tx_queue_sem);

   233

   234

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

   235

        list_del(&frame->queue);

   236

        dev_kfree_skb(frame->skb);

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        kfree(frame);

   238

    }

   239

    eoe->tx_queued_frames = 0;

   240

   241

    up(&eoe->tx_queue_sem);

   242

}

   243

   244

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

   245

   246

/** Sends a frame or the next fragment.

   247

 */

   248

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

   249

{

   250

    size_t remaining_size, current_size, complete_offset;

   251

    unsigned int last_fragment;

   252

    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

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    unsigned int i;

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#endif

   256

   257

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

   258

   259

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

   260

        current_size = remaining_size;

   261

        last_fragment = 1;

   262

    } 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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    }

   266

   267

    if (eoe->tx_fragment_number) {

   268

        complete_offset = eoe->tx_offset / 32;

   269

    }

   270

    else {

   271

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

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        complete_offset = remaining_size / 32 + 1;

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    }

   274

   275

#if EOE_DEBUG_LEVEL >= 2

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    EC_DBG("EoE %s TX sending fragment %u%s with %u octets (%u)."

   277

           " %u frames queued.\n", eoe->dev->name, eoe->tx_fragment_number,

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

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           eoe->tx_queued_frames);

   280

#endif

   281

   282

#if EOE_DEBUG_LEVEL >= 3

   283

    EC_DBG("");

   284

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

   285

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

   286

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

   287

            printk("\n");

   288

            EC_DBG("");

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        }

   290

    }

   291

    printk("\n");

   292

#endif

   293

   294

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

   295

            0x02, current_size + 4);

   296

    if (IS_ERR(data))

   297

        return PTR_ERR(data);

   298

   299

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

   300

    EC_WRITE_U8 (data + 1, last_fragment);

   301

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

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                            (complete_offset & 0x3F) << 6 |

   303

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

   304

   305

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

   306

    eoe->queue_datagram = 1;

   307

   308

    eoe->tx_offset += current_size;

   309

    eoe->tx_fragment_number++;

   310

    return 0;

   311

}

   312

   313

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

   314

   315

/** Runs the EoE state machine.

   316

 */

   317

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

   318

{

   319

    if (!eoe->opened)

   320

        return;

   321

   322

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

   323

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

   324

        return;

   325

   326

    // call state function

   327

    eoe->state(eoe);

   328

   329

    // update statistics

   330

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

   331

        eoe->rx_rate = eoe->rx_counter;

   332

        eoe->tx_rate = eoe->tx_counter;

   333

        eoe->rx_counter = 0;

   334

        eoe->tx_counter = 0;

   335

        eoe->rate_jiffies = jiffies;

   336

    }

   337

   338

    ec_datagram_output_stats(&eoe->datagram);

   339

}

   340

   341

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

   342

   343

/** Queues the datagram, if necessary.

   344

 */

   345

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

   346

{

   347

   if (eoe->queue_datagram) {

   348

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

   349

       eoe->queue_datagram = 0;

   350

   }

   351

}

   352

   353

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

   354

   355

/** Returns the state of the device.

   356

 *

   357

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

   358

 */

   359

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

   360

{

   361

    return eoe->opened;

   362

}

   363

   364

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

   365

   366

/** Returns the idle state.

   367

 *

   368

 * \retval 1 The device is idle.

   369

 * \retval 0 The device is busy.

   370

 */

   371

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

   372

{

   373

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

   374

}

   375

   376

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

   377

 *  STATE PROCESSING FUNCTIONS

   378

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

   379

   380

/** State: RX_START.

   381

 *

   382

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

   383

 * slave's mailbox for a new EoE datagram.

   384

 */

   385

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

   386

{

   387

    if (eoe->slave->error_flag ||

   388

            !eoe->slave->master->main_device.link_state) {

   389

        eoe->rx_idle = 1;

   390

        eoe->tx_idle = 1;

   391

        return;

   392

    }

   393

   394

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

   395

    eoe->queue_datagram = 1;

   396

    eoe->state = ec_eoe_state_rx_check;

   397

}

   398

   399

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

   400

   401

/** State: RX_CHECK.

   402

 *

   403

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

   404

 * datagram, if new data is available.

   405

 */

   406

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

   407

{

   408

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

   409

        eoe->stats.rx_errors++;

   410

#if EOE_DEBUG_LEVEL >= 1

   411

        EC_WARN("Failed to receive mbox check datagram for %s.\n",

   412

                eoe->dev->name);

   413

#endif

   414

        eoe->state = ec_eoe_state_tx_start;

   415

        return;

   416

    }

   417

   418

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

   419

        eoe->rx_idle = 1;

   420

        eoe->state = ec_eoe_state_tx_start;

   421

        return;

   422

    }

   423

   424

    eoe->rx_idle = 0;

   425

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

   426

    eoe->queue_datagram = 1;

   427

    eoe->state = ec_eoe_state_rx_fetch;

   428

}

   429

   430

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

   431

   432

/** State: RX_FETCH.

   433

 *

   434

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

   435

 * datagram.

   436

 */

   437

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

   438

{

   439

    size_t rec_size, data_size;

   440

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

   441

    uint8_t frame_number, fragment_offset, fragment_number;

   442

    off_t offset;

   443

#if EOE_DEBUG_LEVEL >= 3

   444

    unsigned int i;

   445

#endif

   446

   447

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

   448

        eoe->stats.rx_errors++;

   449

#if EOE_DEBUG_LEVEL >= 1

   450

        EC_WARN("Failed to receive mbox fetch datagram for %s.\n",

   451

                eoe->dev->name);

   452

#endif

   453

        eoe->state = ec_eoe_state_tx_start;

   454

        return;

   455

    }

   456

   457

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

   458

            &mbox_prot, &rec_size);

   459

    if (IS_ERR(data)) {

   460

        eoe->stats.rx_errors++;

   461

#if EOE_DEBUG_LEVEL >= 1

   462

        EC_WARN("Invalid mailbox response for %s.\n",

   463

                eoe->dev->name);

   464

#endif

   465

        eoe->state = ec_eoe_state_tx_start;

   466

        return;

   467

    }

   468

   469

    if (mbox_prot != 0x02) { // EoE FIXME mailbox handler necessary

   470

        eoe->stats.rx_errors++;

   471

#if EOE_DEBUG_LEVEL >= 1

   472

        EC_WARN("Other mailbox protocol response for %s.\n",

   473

                eoe->dev->name);

   474

#endif

   475

        eoe->state = ec_eoe_state_tx_start;

   476

        return;

   477

    }

   478

   479

    frame_type = EC_READ_U16(data) & 0x000F;

   480

   481

    if (frame_type != 0x00) {

   482

#if EOE_DEBUG_LEVEL >= 1

   483

        EC_WARN("%s: Other frame received. Dropping.\n", eoe->dev->name);

   484

#endif

   485

        eoe->stats.rx_dropped++;