1

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

     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,

    14

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

    15

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

    16

 *  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

    20

 *  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

    26

 *  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/netdevice.h>

    38

#include <linux/etherdevice.h>

    39

    40

#include "globals.h"

    41

#include "master.h"

    42

#include "slave.h"

    43

#include "mailbox.h"

    44

#include "ethernet.h"

    45

    46

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

    47

    48

/** Defines the debug level of EoE processing.

    49

 *

    50

 * 0 = No debug messages.

    51

 * 1 = Output warnings.

    52

 * 2 = Output actions.

    53

 * 3 = Output actions and frame data.

    54

 */

    55

#define EOE_DEBUG_LEVEL 1

    56

    57

/** Size of the EoE tx queue.

    58

 */

    59

#define EC_EOE_TX_QUEUE_SIZE 100

    60

    61

/** Number of tries.

    62

 */

    63

#define EC_EOE_TRIES 100

    64

    65

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

    66

    67

void ec_eoe_flush(ec_eoe_t *);

    68

    69

// state functions

    70

void ec_eoe_state_rx_start(ec_eoe_t *);

    71

void ec_eoe_state_rx_check(ec_eoe_t *);

    72

void ec_eoe_state_rx_fetch(ec_eoe_t *);

    73

void ec_eoe_state_tx_start(ec_eoe_t *);

    74

void ec_eoe_state_tx_sent(ec_eoe_t *);

    75

    76

// net_device functions

    77

int ec_eoedev_open(struct net_device *);

    78

int ec_eoedev_stop(struct net_device *);

    79

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

    80

struct net_device_stats *ec_eoedev_stats(struct net_device *);

    81

    82

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

    83

    84

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

    85

static const struct net_device_ops ec_eoedev_ops = {

    86

    .ndo_open = ec_eoedev_open,

    87

    .ndo_stop = ec_eoedev_stop,

    88

    .ndo_start_xmit = ec_eoedev_tx,

    89

    .ndo_get_stats = ec_eoedev_stats,

    90

};

    91

#endif

    92

    93

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

    94

    95

/** EoE constructor.

    96

 *

    97

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

    98

 */

    99

int ec_eoe_init(

   100

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

   101

        ec_slave_t *slave /**< EtherCAT slave */

   102

        )

   103

{

   104

    ec_eoe_t **priv;

   105

    int i, ret = 0;

   106

    char name[EC_DATAGRAM_NAME_SIZE];

   107

   108

    eoe->slave = slave;

   109

   110

    ec_datagram_init(&eoe->datagram);

   111

    eoe->queue_datagram = 0;

   112

    eoe->state = ec_eoe_state_rx_start;

   113

    eoe->opened = 0;

   114

    eoe->rx_skb = NULL;

   115

    eoe->rx_expected_fragment = 0;

   116

    INIT_LIST_HEAD(&eoe->tx_queue);

   117

    eoe->tx_frame = NULL;

   118

    eoe->tx_queue_active = 0;

   119

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   120

    eoe->tx_queued_frames = 0;

   121

    init_MUTEX(&eoe->tx_queue_sem);

   122

    eoe->tx_frame_number = 0xFF;

   123

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

   124

   125

    eoe->rx_counter = 0;

   126

    eoe->tx_counter = 0;

   127

    eoe->rx_rate = 0;

   128

    eoe->tx_rate = 0;

   129

    eoe->rate_jiffies = 0;

   130

    eoe->rx_idle = 1;

   131

    eoe->tx_idle = 1;

   132

   133

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

   134

     * like hyphens etc. in interface names. */

   135

    if (slave->sii.alias) {

   136

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   137

                "eoe%ua%u", slave->master->index, slave->sii.alias);

   138

    } else {

   139

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   140

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

   141

    }

   142

   143

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

   144

   145

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

   146

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

   147

        ret = -ENODEV;

   148

        goto out_return;

   149

    }

   150

   151

    // initialize net_device

   152

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

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    eoe->dev->netdev_ops = &ec_eoedev_ops;

   154

#else

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    eoe->dev->open = ec_eoedev_open;

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    eoe->dev->stop = ec_eoedev_stop;

   157

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   158

    eoe->dev->get_stats = ec_eoedev_stats;

   159

#endif

   160

   161

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

   162

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

   163

   164

    // initialize private data

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    priv = netdev_priv(eoe->dev);

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    *priv = eoe;

   167

   168

    // 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".

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#if 0

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

   174

#endif

   175

   176

    // connect the net_device to the kernel

   177

    ret = register_netdev(eoe->dev);

   178

    if (ret) {

   179

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

   180

        goto out_free;

   181

    }

   182

   183

    // make the last address octet unique

   184

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

   185

    return 0;

   186

   187

 out_free:

   188

    free_netdev(eoe->dev);

   189

    eoe->dev = NULL;

   190

 out_return:

   191

    return ret;

   192

}

   193

   194

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

   195

   196

/** EoE destructor.

   197

 *

   198

 * Unregisteres the net_device and frees allocated memory.

   199

 */

   200

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

   201

{

   202

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

   203

   204

    // empty transmit queue

   205

    ec_eoe_flush(eoe);

   206

   207

    if (eoe->tx_frame) {

   208

        dev_kfree_skb(eoe->tx_frame->skb);

   209

        kfree(eoe->tx_frame);

   210

    }

   211

   212

    if (eoe->rx_skb)

   213

        dev_kfree_skb(eoe->rx_skb);

   214

   215

    free_netdev(eoe->dev);

   216

   217

    ec_datagram_clear(&eoe->datagram);

   218

}

   219

   220

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

   221

   222

/** Empties the transmit queue.

   223

 */

   224

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

   225

{

   226

    ec_eoe_frame_t *frame, *next;

   227

   228

    down(&eoe->tx_queue_sem);

   229

   230

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

   231

        list_del(&frame->queue);

   232

        dev_kfree_skb(frame->skb);

   233

        kfree(frame);

   234

    }

   235

    eoe->tx_queued_frames = 0;

   236

   237

    up(&eoe->tx_queue_sem);

   238

}

   239

   240

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

   241

   242

/** Sends a frame or the next fragment.

   243

 */

   244

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

   245

{

   246

    size_t remaining_size, current_size, complete_offset;

   247

    unsigned int last_fragment;

   248

    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

   250

    unsigned int i;

   251

#endif

   252

   253

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

   254

   255

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

   256

        current_size = remaining_size;

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        last_fragment = 1;

   258

    } else {

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

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        last_fragment = 0;

   261

    }

   262

   263

    if (eoe->tx_fragment_number) {

   264

        complete_offset = eoe->tx_offset / 32;

   265

    }

   266

    else {

   267

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

   268

        complete_offset = remaining_size / 32 + 1;

   269

    }

   270

   271

#if EOE_DEBUG_LEVEL >= 2

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

   273

           " %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);

   276

#endif

   277

   278

#if EOE_DEBUG_LEVEL >= 3

   279

    EC_DBG("");

   280

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

   281

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

   282

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

   283

            printk("\n");

   284

            EC_DBG("");

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        }

   286

    }

   287

    printk("\n");

   288

#endif

   289

   290

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

   291

            0x02, current_size + 4);

   292

    if (IS_ERR(data))

   293

        return PTR_ERR(data);

   294

   295

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

   296

    EC_WRITE_U8 (data + 1, last_fragment);

   297

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

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                            (complete_offset & 0x3F) << 6 |

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

   300

   301

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

   302

    eoe->queue_datagram = 1;

   303

   304

    eoe->tx_offset += current_size;

   305

    eoe->tx_fragment_number++;

   306

    return 0;

   307

}

   308

   309

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

   310

   311

/** Runs the EoE state machine.

   312

 */

   313

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

   314

{

   315

    if (!eoe->opened)

   316

        return;

   317

   318

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

   319

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

   320

        return;

   321

   322

    // call state function

   323

    eoe->state(eoe);

   324

   325

    // update statistics

   326

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

   327

        eoe->rx_rate = eoe->rx_counter;

   328

        eoe->tx_rate = eoe->tx_counter;

   329

        eoe->rx_counter = 0;

   330

        eoe->tx_counter = 0;

   331

        eoe->rate_jiffies = jiffies;

   332

    }

   333

   334

    ec_datagram_output_stats(&eoe->datagram);

   335

}

   336

   337

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

   338

   339

/** Queues the datagram, if necessary.

   340

 */

   341

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

   342

{

   343

   if (eoe->queue_datagram) {

   344

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

   345

       eoe->queue_datagram = 0;

   346

   }

   347

}

   348

   349

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

   350

   351

/** Returns the state of the device.

   352

 *

   353

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

   354

 */

   355

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

   356

{

   357

    return eoe->opened;

   358

}

   359

   360

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

   361

   362

/** Returns the idle state.

   363

 *

   364

 * \retval 1 The device is idle.

   365

 * \retval 0 The device is busy.

   366

 */

   367

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

   368

{

   369

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

   370

}

   371

   372

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

   373

 *  STATE PROCESSING FUNCTIONS

   374

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

   375

   376

/** State: RX_START.

   377

 *

   378

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

   379

 * slave's mailbox for a new EoE datagram.

   380

 */

   381

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

   382

{

   383

    if (eoe->slave->error_flag ||

   384

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

   385

        eoe->rx_idle = 1;

   386

        eoe->tx_idle = 1;

   387

        return;

   388

    }

   389

   390

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

   391

    eoe->queue_datagram = 1;

   392

    eoe->state = ec_eoe_state_rx_check;

   393

}

   394

   395

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

   396

   397

/** State: RX_CHECK.

   398

 *

   399

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

   400

 * datagram, if new data is available.

   401

 */

   402

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

   403

{

   404

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

   405

        eoe->stats.rx_errors++;

   406

#if EOE_DEBUG_LEVEL >= 1

   407

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

   408

                eoe->dev->name);

   409

#endif

   410

        eoe->state = ec_eoe_state_tx_start;

   411

        return;

   412

    }

   413

   414

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

   415

        eoe->rx_idle = 1;

   416

        eoe->state = ec_eoe_state_tx_start;

   417

        return;

   418

    }

   419

   420

    eoe->rx_idle = 0;

   421

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

   422

    eoe->queue_datagram = 1;

   423

    eoe->state = ec_eoe_state_rx_fetch;

   424

}

   425

   426

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

   427

   428

/** State: RX_FETCH.

   429

 *

   430

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

   431

 * datagram.

   432

 */

   433

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

   434

{

   435

    size_t rec_size, data_size;

   436

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

   437

    uint8_t frame_number, fragment_offset, fragment_number;

   438

    off_t offset;

   439

#if EOE_DEBUG_LEVEL >= 3

   440

    unsigned int i;

   441

#endif

   442

   443

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

   444

        eoe->stats.rx_errors++;

   445

#if EOE_DEBUG_LEVEL >= 1

   446

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

   447

                eoe->dev->name);

   448

#endif

   449

        eoe->state = ec_eoe_state_tx_start;

   450

        return;

   451

    }

   452

   453

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

   454

            &mbox_prot, &rec_size);

   455

    if (IS_ERR(data)) {

   456

        eoe->stats.rx_errors++;

   457

#if EOE_DEBUG_LEVEL >= 1

   458

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

   459

                eoe->dev->name);

   460

#endif

   461

        eoe->state = ec_eoe_state_tx_start;

   462

        return;

   463

    }

   464

   465

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

   466

        eoe->stats.rx_errors++;

   467

#if EOE_DEBUG_LEVEL >= 1

   468

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

   469

                eoe->dev->name);

   470

#endif

   471

        eoe->state = ec_eoe_state_tx_start;

   472

        return;

   473

    }

   474

   475

    frame_type = EC_READ_U16(data) & 0x000F;

   476

   477

    if (frame_type != 0x00) {

   478

#if EOE_DEBUG_LEVEL >= 1

   479

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

   480

#endif

   481

        eoe->stats.rx_dropped++;

   482

        eoe->state = ec_eoe_state_tx_start;

   483

        return;

   484

    }

   485