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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

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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.

    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

    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

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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/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

/** EoE constructor.

    85

 *

    86

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

    87

 */

    88

int ec_eoe_init(

    89

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

    90

        ec_slave_t *slave /**< EtherCAT slave */

    91

        )

    92

{

    93

    ec_eoe_t **priv;

    94

    int i, ret = 0;

    95

    char name[EC_DATAGRAM_NAME_SIZE];

    96

    97

    eoe->slave = slave;

    98

    99

    ec_datagram_init(&eoe->datagram);

   100

    eoe->queue_datagram = 0;

   101

    eoe->state = ec_eoe_state_rx_start;

   102

    eoe->opened = 0;

   103

    eoe->rx_skb = NULL;

   104

    eoe->rx_expected_fragment = 0;

   105

    INIT_LIST_HEAD(&eoe->tx_queue);

   106

    eoe->tx_frame = NULL;

   107

    eoe->tx_queue_active = 0;

   108

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   109

    eoe->tx_queued_frames = 0;

   110

    init_MUTEX(&eoe->tx_queue_sem);

   111

    eoe->tx_frame_number = 0xFF;

   112

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

   113

   114

    eoe->rx_counter = 0;

   115

    eoe->tx_counter = 0;

   116

    eoe->rx_rate = 0;

   117

    eoe->tx_rate = 0;

   118

    eoe->rate_jiffies = 0;

   119

    eoe->rx_idle = 1;

   120

    eoe->tx_idle = 1;

   121

   122

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

   123

     * like hyphens etc. in interface names. */

   124

    if (slave->sii.alias) {

   125

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   126

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

   127

    } else {

   128

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   129

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

   130

    }

   131

   132

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

   133

   134

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

   135

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

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        ret = -ENODEV;

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        goto out_return;

   138

    }

   139

   140

    // initialize net_device

   141

    eoe->dev->open = ec_eoedev_open;

   142

    eoe->dev->stop = ec_eoedev_stop;

   143

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   144

    eoe->dev->get_stats = ec_eoedev_stats;

   145

   146

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

   147

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

   148

   149

    // initialize private data

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    priv = netdev_priv(eoe->dev);

   151

    *priv = eoe;

   152

   153

    // 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;

   159

#endif

   160

   161

    // connect the net_device to the kernel

   162

    ret = register_netdev(eoe->dev);

   163

    if (ret) {

   164

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

   165

        goto out_free;

   166

    }

   167

   168

    // make the last address octet unique

   169

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

   170

    return 0;

   171

   172

 out_free:

   173

    free_netdev(eoe->dev);

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    eoe->dev = NULL;

   175

 out_return:

   176

    return ret;

   177

}

   178

   179

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

   180

   181

/** EoE destructor.

   182

 *

   183

 * Unregisteres the net_device and frees allocated memory.

   184

 */

   185

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

   186

{

   187

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

   188

   189

    // empty transmit queue

   190

    ec_eoe_flush(eoe);

   191

   192

    if (eoe->tx_frame) {

   193

        dev_kfree_skb(eoe->tx_frame->skb);

   194

        kfree(eoe->tx_frame);

   195

    }

   196

   201

   202

    ec_datagram_clear(&eoe->datagram);

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}

   204

   205

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

   206

   207

/** Empties the transmit queue.

   208

 */

   209

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

   210

{

   211

    ec_eoe_frame_t *frame, *next;

   212

   213

    down(&eoe->tx_queue_sem);

   214

   215

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

   216

        list_del(&frame->queue);

   217

        dev_kfree_skb(frame->skb);

   218

        kfree(frame);

   219

    }

   220

    eoe->tx_queued_frames = 0;

   221

   222

    up(&eoe->tx_queue_sem);

   223

}

   224

   225

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

   226

   227

/** Sends a frame or the next fragment.

   228

 */

   229

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

   230

{

   231

    size_t remaining_size, current_size, complete_offset;

   232

    unsigned int last_fragment;

   233

    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

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    unsigned int i;

   236

#endif

   237

   238

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

   239

   240

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

   241

        current_size = remaining_size;

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        last_fragment = 1;

   243

    } else {

   244

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

   245

        last_fragment = 0;

   246

    }

   247

   248

    if (eoe->tx_fragment_number) {

   249

        complete_offset = eoe->tx_offset / 32;

   250

    }

   251

    else {

   252

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

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        complete_offset = remaining_size / 32 + 1;

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    }

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#if EOE_DEBUG_LEVEL >= 2

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    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);

   261

#endif

   262

   263

#if EOE_DEBUG_LEVEL >= 3

   264

    EC_DBG("");

   265

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

   266

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

   267

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

   268

            printk("\n");

   269

            EC_DBG("");

   270

        }

   271

    }

   272

    printk("\n");

   273

#endif

   274

   275

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

   276

            0x02, current_size + 4);

   277

    if (IS_ERR(data))

   278

        return PTR_ERR(data);

   279

   280

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

   281

    EC_WRITE_U8 (data + 1, last_fragment);

   282

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

   283

                            (complete_offset & 0x3F) << 6 |

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

   285

   286

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

   287

    eoe->queue_datagram = 1;

   288

   289

    eoe->tx_offset += current_size;

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    eoe->tx_fragment_number++;

   291

    return 0;

   292

}

   293

   294

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

   295

   296

/** Runs the EoE state machine.

   297

 */

   298

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

   299

{

   300

    if (!eoe->opened)

   301

        return;

   302

   303

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

   304

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

   305

        return;

   306

   307

    // call state function

   308

    eoe->state(eoe);

   309

   310

    // update statistics

   311

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

   312

        eoe->rx_rate = eoe->rx_counter;

   313

        eoe->tx_rate = eoe->tx_counter;

   314

        eoe->rx_counter = 0;

   315

        eoe->tx_counter = 0;

   316

        eoe->rate_jiffies = jiffies;

   317

    }

   318

   319

    ec_datagram_output_stats(&eoe->datagram);

   320

}

   321

   322

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

   323

   324

/** Queues the datagram, if necessary.

   325

 */

   326

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

   327

{

   328

   if (eoe->queue_datagram) {

   329

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

   330

       eoe->queue_datagram = 0;

   331

   }

   332

}

   333

   334

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

   335

   336

/** Returns the state of the device.

   337

 *

   338

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

   339

 */

   340

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

   341

{

   342

    return eoe->opened;

   343

}

   344

   345

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

   346

   347

/** Returns the idle state.

   348

 *

   349

 * \retval 1 The device is idle.

   350

 * \retval 0 The device is busy.

   351

 */

   352

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

   353

{

   354

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

   355

}

   356

   357

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

   358

 *  STATE PROCESSING FUNCTIONS

   359

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

   360

   361

/** State: RX_START.

   362

 *

   363

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

   364

 * slave's mailbox for a new EoE datagram.

   365

 */

   366

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

   367

{

   368

    if (eoe->slave->error_flag ||

   369

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

   370

        eoe->rx_idle = 1;

   371

        eoe->tx_idle = 1;

   372

        return;

   373

    }

   374

   375

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

   376

    eoe->queue_datagram = 1;

   377

    eoe->state = ec_eoe_state_rx_check;

   378

}

   379

   380

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

   381

   382

/** State: RX_CHECK.

   383

 *

   384

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

   385

 * datagram, if new data is available.

   386

 */

   387

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

   388

{

   389

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

   390

        eoe->stats.rx_errors++;

   391

#if EOE_DEBUG_LEVEL >= 1

   392

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

   393

                eoe->dev->name);

   394

#endif

   395

        eoe->state = ec_eoe_state_tx_start;

   396

        return;

   397

    }

   398

   399

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

   400

        eoe->rx_idle = 1;

   401

        eoe->state = ec_eoe_state_tx_start;

   402

        return;

   403

    }

   404

   405

    eoe->rx_idle = 0;

   406

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

   407

    eoe->queue_datagram = 1;

   408

    eoe->state = ec_eoe_state_rx_fetch;

   409

}

   410

   411

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

   412

   413

/** State: RX_FETCH.

   414

 *

   415

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

   416

 * datagram.

   417

 */

   418

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

   419

{

   420

    size_t rec_size, data_size;

   421

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

   422

    uint8_t frame_number, fragment_offset, fragment_number;

   423

    off_t offset;

   424

#if EOE_DEBUG_LEVEL >= 3

   425

    unsigned int i;

   426

#endif

   427

   428

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

   429

        eoe->stats.rx_errors++;

   430

#if EOE_DEBUG_LEVEL >= 1

   431

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

   432

                eoe->dev->name);

   433

#endif

   434

        eoe->state = ec_eoe_state_tx_start;

   435

        return;

   436

    }

   437

   438

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

   439

            &mbox_prot, &rec_size);

   440

    if (IS_ERR(data)) {

   441

        eoe->stats.rx_errors++;

   442

#if EOE_DEBUG_LEVEL >= 1

   443

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

   444

                eoe->dev->name);

   445

#endif

   446

        eoe->state = ec_eoe_state_tx_start;

   447

        return;

   448

    }

   449

   450

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

   451

        eoe->stats.rx_errors++;

   452

#if EOE_DEBUG_LEVEL >= 1

   453

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

   454

                eoe->dev->name);

   455

#endif

   456

        eoe->state = ec_eoe_state_tx_start;

   457

        return;

   458

    }

   459

   460

    frame_type = EC_READ_U16(data) & 0x000F;

   461

   462

    if (frame_type != 0x00) {

   463

#if EOE_DEBUG_LEVEL >= 1

   464

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

   465

#endif

   466

        eoe->stats.rx_dropped++;

   467

        eoe->state = ec_eoe_state_tx_start;

   468

        return;

   469

    }

   470

   471

    // EoE Fragment Request received

   472

   473

    last_fragment = (EC_READ_U16(data) >> 8) & 0x0001;

   474

    time_appended = (EC_READ_U16(data) >> 9) & 0x0001;

   475

    fragment_number = EC_READ_U16(data + 2) & 0x003F;

   476

    fragment_offset = (EC_READ_U16(data + 2) >> 6) & 0x003F;

   477

    frame_number = (EC_READ_U16(data + 2) >> 12) & 0x000F;

   478

   479

#if EOE_DEBUG_LEVEL >= 2

   480

    EC_DBG("EoE %s RX fragment %u%s, offset %u, frame %u%s,"

   481

           " %u octets\n", eoe->dev->name, fragment_number,

   482

           last_fragment ? "" : "+", fragment_offset, frame_number, 

   483

           time_appended ? ", + timestamp" : "",

   484

           time_appended ? rec_size - 8 : rec_size - 4);

   485

#endif