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/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"

    45

#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 *);

    74

void ec_eoe_state_tx_start(ec_eoe_t *);

    75

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

static const struct net_device_ops ec_eoedev_ops = {

    87

    .ndo_open = ec_eoedev_open,

    88

    .ndo_stop = ec_eoedev_stop,

    89

    .ndo_start_xmit = ec_eoedev_tx,

    90

    .ndo_get_stats = ec_eoedev_stats,

    91

};

    92

#endif

    93

    94

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

    95

    96

/** EoE constructor.

    97

 *

    98

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

    99

 */

   100

int ec_eoe_init(

   101

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

   102

        ec_slave_t *slave /**< EtherCAT slave */

   103

        )

   104

{

   105

    ec_eoe_t **priv;

   106

    int i, ret = 0;

   107

    char name[EC_DATAGRAM_NAME_SIZE];

   108

   109

    eoe->slave = slave;

   110

   111

    ec_datagram_init(&eoe->datagram);

   112

    eoe->queue_datagram = 0;

   113

    eoe->state = ec_eoe_state_rx_start;

   114

    eoe->opened = 0;

   115

    eoe->rx_skb = NULL;

   116

    eoe->rx_expected_fragment = 0;

   117

    INIT_LIST_HEAD(&eoe->tx_queue);

   118

    eoe->tx_frame = NULL;

   119

    eoe->tx_queue_active = 0;

   120

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   121

    eoe->tx_queued_frames = 0;

   122

   123

    sema_init(&eoe->tx_queue_sem, 1);

   124

    eoe->tx_frame_number = 0xFF;

   125

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

   126

   127

    eoe->rx_counter = 0;

   128

    eoe->tx_counter = 0;

   129

    eoe->rx_rate = 0;

   130

    eoe->tx_rate = 0;

   131

    eoe->rate_jiffies = 0;

   132

    eoe->rx_idle = 1;

   133

    eoe->tx_idle = 1;

   134

   135

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

   136

     * like hyphens etc. in interface names. */

   137

    if (slave->sii.alias) {

   138

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   139

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

   140

    } else {

   141

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   142

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

   143

    }

   144

   145

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

   146

   147

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

   148

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

   149

        ret = -ENODEV;

   150

        goto out_return;

   151

    }

   152

   153

    // initialize net_device

   154

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

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    eoe->dev->netdev_ops = &ec_eoedev_ops;

   156

#else

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    eoe->dev->open = ec_eoedev_open;

   158

    eoe->dev->stop = ec_eoedev_stop;

   159

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   160

    eoe->dev->get_stats = ec_eoedev_stats;

   161

#endif

   162

   163

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

   164

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

   165

   166

    // initialize private data

   167

    priv = netdev_priv(eoe->dev);

   168

    *priv = eoe;

   169

   170

    // Usually setting the MTU appropriately makes the upper layers

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

   172

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

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    // is done "manually".

   174

#if 0

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

   176

#endif

   177

   178

    // connect the net_device to the kernel

   179

    ret = register_netdev(eoe->dev);

   180

    if (ret) {

   181

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

   182

        goto out_free;

   183

    }

   184

   185

    // make the last address octet unique

   186

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

   187

    return 0;

   188

   189

 out_free:

   190

    free_netdev(eoe->dev);

   191

    eoe->dev = NULL;

   192

 out_return:

   193

    return ret;

   194

}

   195

   196

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

   197

   198

/** EoE destructor.

   199

 *

   200

 * Unregisteres the net_device and frees allocated memory.

   201

 */

   202

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

   203

{

   204

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

   205

   206

    // empty transmit queue

   207

    ec_eoe_flush(eoe);

   208

   209

    if (eoe->tx_frame) {

   210

        dev_kfree_skb(eoe->tx_frame->skb);

   211

        kfree(eoe->tx_frame);

   212

    }

   213

   214

    if (eoe->rx_skb)

   215

        dev_kfree_skb(eoe->rx_skb);

   216

   217

    free_netdev(eoe->dev);

   218

   219

    ec_datagram_clear(&eoe->datagram);

   220

}

   221

   222

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

   223

   224

/** Empties the transmit queue.

   225

 */

   226

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

   227

{

   228

    ec_eoe_frame_t *frame, *next;

   229

   230

    down(&eoe->tx_queue_sem);

   231

   232

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

   233

        list_del(&frame->queue);

   234

        dev_kfree_skb(frame->skb);

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        kfree(frame);

   236

    }

   237

    eoe->tx_queued_frames = 0;

   238

   239

    up(&eoe->tx_queue_sem);

   240

}

   241

   242

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

   243

   244

/** Sends a frame or the next fragment.

   245

 */

   246

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

   247

{

   248

    size_t remaining_size, current_size, complete_offset;

   249

    unsigned int last_fragment;

   250

    uint8_t *data;

   251

#if EOE_DEBUG_LEVEL >= 3

   252

    unsigned int i;

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#endif

   254

   255

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

   256

   257

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

   258

        current_size = remaining_size;

   259

        last_fragment = 1;

   260

    } else {

   261

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

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        last_fragment = 0;

   263

    }

   264

   265

    if (eoe->tx_fragment_number) {

   266

        complete_offset = eoe->tx_offset / 32;

   267

    }

   268

    else {

   269

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

   270

        complete_offset = remaining_size / 32 + 1;

   271

    }

   272

   273

#if EOE_DEBUG_LEVEL >= 2

   274

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

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           " %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);

   278

#endif

   279

   280

#if EOE_DEBUG_LEVEL >= 3

   281

    EC_DBG("");

   282

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

   283

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

   284

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

   285

            printk("\n");

   286

            EC_DBG("");

   287

        }

   288

    }

   289

    printk("\n");

   290

#endif

   291

   292

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

   293

            0x02, current_size + 4);

   294

    if (IS_ERR(data))

   295

        return PTR_ERR(data);

   296

   297

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

   298

    EC_WRITE_U8 (data + 1, last_fragment);

   299

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

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                            (complete_offset & 0x3F) << 6 |

   301

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

   302

   303

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

   304

    eoe->queue_datagram = 1;

   305

   306

    eoe->tx_offset += current_size;

   307

    eoe->tx_fragment_number++;

   308

    return 0;

   309

}

   310

   311

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

   312

   313

/** Runs the EoE state machine.

   314

 */

   315

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

   316

{

   317

    if (!eoe->opened)

   318

        return;

   319

   320

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

   321

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

   322

        return;

   323

   324

    // call state function

   325

    eoe->state(eoe);

   326

   327

    // update statistics

   328

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

   329

        eoe->rx_rate = eoe->rx_counter;

   330

        eoe->tx_rate = eoe->tx_counter;

   331

        eoe->rx_counter = 0;

   332

        eoe->tx_counter = 0;

   333

        eoe->rate_jiffies = jiffies;

   334

    }

   335

   336

    ec_datagram_output_stats(&eoe->datagram);

   337

}

   338

   339

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

   340

   341

/** Queues the datagram, if necessary.

   342

 */

   343

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

   344

{

   345

   if (eoe->queue_datagram) {

   346

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

   347

       eoe->queue_datagram = 0;

   348

   }

   349

}

   350

   351

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

   352

   353

/** Returns the state of the device.

   354

 *

   355

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

   356

 */

   357

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

   358

{

   359

    return eoe->opened;

   360

}

   361

   362

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

   363

   364

/** Returns the idle state.

   365

 *

   366

 * \retval 1 The device is idle.

   367

 * \retval 0 The device is busy.

   368

 */

   369

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

   370

{

   371

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

   372

}

   373

   374

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

   375

 *  STATE PROCESSING FUNCTIONS

   376

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

   377

   378

/** State: RX_START.

   379

 *

   380

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

   381

 * slave's mailbox for a new EoE datagram.

   382

 */

   383

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

   384

{

   385

    if (eoe->slave->error_flag ||

   386

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

   387

        eoe->rx_idle = 1;

   388

        eoe->tx_idle = 1;

   389

        return;

   390

    }

   391

   392

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

   393

    eoe->queue_datagram = 1;

   394

    eoe->state = ec_eoe_state_rx_check;

   395

}

   396

   397

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

   398

   399

/** State: RX_CHECK.

   400

 *

   401

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

   402

 * datagram, if new data is available.

   403

 */

   404

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

   405

{

   406

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

   407

        eoe->stats.rx_errors++;

   408

#if EOE_DEBUG_LEVEL >= 1

   409

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

   410

                eoe->dev->name);

   411

#endif

   412

        eoe->state = ec_eoe_state_tx_start;

   413

        return;

   414

    }

   415

   416

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

   417

        eoe->rx_idle = 1;

   418

        eoe->state = ec_eoe_state_tx_start;

   419

        return;

   420

    }

   421

   422

    eoe->rx_idle = 0;

   423

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

   424

    eoe->queue_datagram = 1;

   425

    eoe->state = ec_eoe_state_rx_fetch;

   426

}

   427

   428

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

   429

   430

/** State: RX_FETCH.

   431

 *

   432

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

   433

 * datagram.

   434

 */

   435

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

   436

{

   437

    size_t rec_size, data_size;

   438

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

   439

    uint8_t frame_number, fragment_offset, fragment_number;

   440

    off_t offset;

   441

#if EOE_DEBUG_LEVEL >= 3

   442

    unsigned int i;

   443

#endif

   444

   445

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

   446

        eoe->stats.rx_errors++;

   447

#if EOE_DEBUG_LEVEL >= 1

   448

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

   449

                eoe->dev->name);

   450

#endif

   451

        eoe->state = ec_eoe_state_tx_start;

   452

        return;

   453

    }

   454

   455

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

   456

            &mbox_prot, &rec_size);

   457

    if (IS_ERR(data)) {

   458

        eoe->stats.rx_errors++;

   459

#if EOE_DEBUG_LEVEL >= 1

   460

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

   461

                eoe->dev->name);

   462

#endif

   463

        eoe->state = ec_eoe_state_tx_start;

   464

        return;

   465

    }

   466

   467

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

   468

        eoe->stats.rx_errors++;

   469

#if EOE_DEBUG_LEVEL >= 1

   470

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

   471

                eoe->dev->name);

   472

#endif

   473

        eoe->state = ec_eoe_state_tx_start;

   474

        return;

   475

    }

   476

   477

    frame_type = EC_READ_U16(data) & 0x000F;

   478

   479

    if (frame_type != 0x00) {

   480

#if EOE_DEBUG_LEVEL >= 1

   481

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

   482

#endif

   483

        eoe->stats.rx_dropped++;

   484

        eoe->state = ec_eoe_state_tx_start;

   485

        return;