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

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 31)

    84

static const struct net_device_ops ec_eoe_netdev_ops =

    85

{

    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

   122

    sema_init(&eoe->tx_queue_sem, 1);

   123

    eoe->tx_frame_number = 0xFF;

   124

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

   125

   126

    eoe->rx_counter = 0;

   127

    eoe->tx_counter = 0;

   128

    eoe->rx_rate = 0;

   129

    eoe->tx_rate = 0;

   130

    eoe->rate_jiffies = 0;

   131

    eoe->rx_idle = 1;

   132

    eoe->tx_idle = 1;

   133

   134

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

   135

     * like hyphens etc. in interface names. */

   136

    if (slave->sii.alias) {

   137

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   138

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

   139

    } else {

   140

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   141

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

   142

    }

   143

   144

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

   145

   146

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

   147

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

   148

        ret = -ENODEV;

   149

        goto out_return;

   150

    }

   151

   152

    // initialize net_device

   153

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 31)

   154

    eoe->dev->netdev_ops = &ec_eoe_netdev_ops;

   155

#else

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    eoe->dev->open = ec_eoedev_open;

   157

    eoe->dev->stop = ec_eoedev_stop;

   158

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   159

    eoe->dev->get_stats = ec_eoedev_stats;

   160

#endif

   161

   162

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

   163

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

   164

   165

    // initialize private data

   166

    priv = netdev_priv(eoe->dev);

   167

    *priv = eoe;

   168

   169

    // Usually setting the MTU appropriately makes the upper layers

   170

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

   171

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

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    // is done "manually".

   173

#if 0

   174

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

   175

#endif

   176

   177

    // connect the net_device to the kernel

   178

    ret = register_netdev(eoe->dev);

   179

    if (ret) {

   180

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

   181

        goto out_free;

   182

    }

   183

   184

    // make the last address octet unique

   185

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

   186

    return 0;

   187

   188

 out_free:

   189

    free_netdev(eoe->dev);

   190

    eoe->dev = NULL;

   191

 out_return:

   192

    return ret;

   193

}

   194

   195

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

   196

   197

/** EoE destructor.

   198

 *

   199

 * Unregisteres the net_device and frees allocated memory.

   200

 */

   201

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

   202

{

   203

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

   204

    free_netdev(eoe->dev);

   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) dev_kfree_skb(eoe->rx_skb);

   215

   216

    ec_datagram_clear(&eoe->datagram);

   217

}

   218

   219

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

   220

   221

/** Empties the transmit queue.

   222

 */

   223

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

   224

{

   225

    ec_eoe_frame_t *frame, *next;

   226

   227

    down(&eoe->tx_queue_sem);

   228

   229

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

   230

        list_del(&frame->queue);

   231

        dev_kfree_skb(frame->skb);

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        kfree(frame);

   233

    }

   234

    eoe->tx_queued_frames = 0;

   235

   236

    up(&eoe->tx_queue_sem);

   237

}

   238

   239

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

   240

   241

/** Sends a frame or the next fragment.

   242

 */

   243

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

   244

{

   245

    size_t remaining_size, current_size, complete_offset;

   246

    unsigned int last_fragment;

   247

    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

   249

    unsigned int i;

   250

#endif

   251

   252

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

   253

   254

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

   255

        current_size = remaining_size;

   256

        last_fragment = 1;

   257

    } else {

   258

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

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        last_fragment = 0;

   260

    }

   261

   262

    if (eoe->tx_fragment_number) {

   263

        complete_offset = eoe->tx_offset / 32;

   264

    }

   265

    else {

   266

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

   267

        complete_offset = remaining_size / 32 + 1;

   268

    }

   269

   270

#if EOE_DEBUG_LEVEL >= 2

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

   272

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

   273

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

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           eoe->tx_queued_frames);

   275

#endif

   276

   277

#if EOE_DEBUG_LEVEL >= 3

   278

    EC_DBG("");

   279

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

   280

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

   281

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

   282

            printk("\n");

   283

            EC_DBG("");

   284

        }

   285

    }

   286

    printk("\n");

   287

#endif

   288

   289

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

   290

            0x02, current_size + 4);

   291

    if (IS_ERR(data))

   292

        return PTR_ERR(data);

   293

   294

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

   295

    EC_WRITE_U8 (data + 1, last_fragment);

   296

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

   297

                            (complete_offset & 0x3F) << 6 |

   298

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

   299

   300

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

   301

    eoe->queue_datagram = 1;

   302

   303

    eoe->tx_offset += current_size;

   304

    eoe->tx_fragment_number++;

   305

    return 0;

   306

}

   307

   308

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

   309

   310

/** Runs the EoE state machine.

   311

 */

   312

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

   313

{

   314

    if (!eoe->opened)

   315

        return;

   316

   317

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

   318

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

   319

        return;

   320

   321

    // call state function

   322

    eoe->state(eoe);

   323

   324

    // update statistics

   325

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

   326

        eoe->rx_rate = eoe->rx_counter;

   327

        eoe->tx_rate = eoe->tx_counter;

   328

        eoe->rx_counter = 0;

   329

        eoe->tx_counter = 0;

   330

        eoe->rate_jiffies = jiffies;

   331

    }

   332

   333

    ec_datagram_output_stats(&eoe->datagram);

   334

}

   335

   336

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

   337

   338

/** Queues the datagram, if necessary.

   339

 */

   340

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

   341

{

   342

   if (eoe->queue_datagram) {

   343

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

   344

       eoe->queue_datagram = 0;

   345

   }

   346

}

   347

   348

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

   349

   350

/** Returns the state of the device.

   351

 *

   352

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

   353

 */

   354

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

   355

{

   356

    return eoe->opened;

   357

}

   358

   359

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

   360

   361

/** Returns the idle state.

   362

 *

   363

 * \retval 1 The device is idle.

   364

 * \retval 0 The device is busy.

   365

 */

   366

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

   367

{

   368

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

   369

}

   370

   371

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

   372

 *  STATE PROCESSING FUNCTIONS

   373

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

   374

   375

/** State: RX_START.

   376

 *

   377

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

   378

 * slave's mailbox for a new EoE datagram.

   379

 */

   380

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

   381

{

   382

    if (eoe->slave->error_flag ||

   383

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

   384

        eoe->rx_idle = 1;

   385

        eoe->tx_idle = 1;

   386

        return;

   387

    }

   388

   389

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

   390

    eoe->queue_datagram = 1;

   391

    eoe->state = ec_eoe_state_rx_check;

   392

}

   393

   394

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

   395

   396

/** State: RX_CHECK.

   397

 *

   398

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

   399

 * datagram, if new data is available.

   400

 */

   401

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

   402

{

   403

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

   404

        eoe->stats.rx_errors++;

   405

#if EOE_DEBUG_LEVEL >= 1

   406

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

   407

                eoe->dev->name);

   408

#endif

   409

        eoe->state = ec_eoe_state_tx_start;

   410

        return;

   411

    }

   412

   413

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

   414

        eoe->rx_idle = 1;

   415

        eoe->state = ec_eoe_state_tx_start;

   416

        return;

   417

    }

   418

   419

    eoe->rx_idle = 0;

   420

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

   421

    eoe->queue_datagram = 1;

   422

    eoe->state = ec_eoe_state_rx_fetch;

   423

}

   424

   425

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

   426

   427

/** State: RX_FETCH.

   428

 *

   429

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

   430

 * datagram.

   431

 */

   432

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

   433

{

   434

    size_t rec_size, data_size;

   435

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

   436

    uint8_t frame_number, fragment_offset, fragment_number;

   437

    off_t offset;

   438

#if EOE_DEBUG_LEVEL >= 3

   439

    unsigned int i;

   440

#endif

   441

   442

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

   443

        eoe->stats.rx_errors++;

   444

#if EOE_DEBUG_LEVEL >= 1

   445

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

   446

                eoe->dev->name);

   447

#endif

   448

        eoe->state = ec_eoe_state_tx_start;

   449

        return;

   450

    }

   451

   452

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

   453

            &mbox_prot, &rec_size);

   454

    if (IS_ERR(data)) {

   455

        eoe->stats.rx_errors++;

   456

#if EOE_DEBUG_LEVEL >= 1

   457

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

   458

                eoe->dev->name);

   459

#endif

   460

        eoe->state = ec_eoe_state_tx_start;

   461

        return;

   462

    }

   463

   464

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

   465

        eoe->stats.rx_errors++;

   466

#if EOE_DEBUG_LEVEL >= 1

   467

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

   468

                eoe->dev->name);

   469

#endif

   470

        eoe->state = ec_eoe_state_tx_start;

   471

        return;

   472

    }

   473

   474

    frame_type = EC_READ_U16(data) & 0x000F;

   475

   476

    if (frame_type != 0x00) {

   477

#if EOE_DEBUG_LEVEL >= 1

   478

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

   479

#endif

   480

        eoe->stats.rx_dropped++;

   481

        eoe->state = ec_eoe_state_tx_start;

   482

        return;

   483

    }

   484

   485

    // EoE Fragment Request received