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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 *);

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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;

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    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++)

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        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:

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    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

    free_netdev(eoe->dev);

   189

   190

    // empty transmit queue

   191

    ec_eoe_flush(eoe);

   192

   193

    if (eoe->tx_frame) {

   194

        dev_kfree_skb(eoe->tx_frame->skb);

   195

        kfree(eoe->tx_frame);

   196

    }

   197

   198

    if (eoe->rx_skb) dev_kfree_skb(eoe->rx_skb);

   199

   200

    ec_datagram_clear(&eoe->datagram);

   201

}

   202

   203

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

   204

   205

/** Empties the transmit queue.

   206

 */

   207

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

   208

{

   209

    ec_eoe_frame_t *frame, *next;

   210

   211

    down(&eoe->tx_queue_sem);

   212

   213

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

   214

        list_del(&frame->queue);

   215

        dev_kfree_skb(frame->skb);

   216

        kfree(frame);

   217

    }

   218

    eoe->tx_queued_frames = 0;

   219

   220

    up(&eoe->tx_queue_sem);

   221

}

   222

   223

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

   224

   225

/** Sends a frame or the next fragment.

   226

 */

   227

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

   228

{

   229

    size_t remaining_size, current_size, complete_offset;

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    unsigned int last_fragment;

   231

    uint8_t *data;

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#if EOE_DEBUG_LEVEL >= 3

   233

    unsigned int i;

   234

#endif

   235

   236

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

   237

   238

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

   239

        current_size = remaining_size;

   240

        last_fragment = 1;

   241

    } else {

   242

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

   243

        last_fragment = 0;

   244

    }

   245

   246

    if (eoe->tx_fragment_number) {

   247

        complete_offset = eoe->tx_offset / 32;

   248

    }

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    else {

   250

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

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        complete_offset = remaining_size / 32 + 1;

   252

    }

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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,

   258

           eoe->tx_queued_frames);

   259

#endif

   260

   261

#if EOE_DEBUG_LEVEL >= 3

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    EC_DBG("");

   263

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

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

   265

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

   266

            printk("\n");

   267

            EC_DBG("");

   268

        }

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    }

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    printk("\n");

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#endif

   272

   273

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

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            0x02, current_size + 4);

   275

    if (IS_ERR(data))

   276

        return PTR_ERR(data);

   277

   278

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

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    EC_WRITE_U8 (data + 1, last_fragment);

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    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));

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   284

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

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    eoe->queue_datagram = 1;

   286

   287

    eoe->tx_offset += current_size;

   288

    eoe->tx_fragment_number++;

   289

    return 0;

   290

}

   291

   292

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

   293

   294

/** Runs the EoE state machine.

   295

 */

   296

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

   297

{

   298

    if (!eoe->opened)

   299

        return;

   300

   301

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

   302

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

   303

        return;

   304

   305

    // call state function

   306

    eoe->state(eoe);

   307

   308

    // update statistics

   309

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

   310

        eoe->rx_rate = eoe->rx_counter;

   311

        eoe->tx_rate = eoe->tx_counter;

   312

        eoe->rx_counter = 0;

   313

        eoe->tx_counter = 0;

   314

        eoe->rate_jiffies = jiffies;

   315

    }

   316

   317

    ec_datagram_output_stats(&eoe->datagram);

   318

}

   319

   320

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

   321

   322

/** Queues the datagram, if necessary.

   323

 */

   324

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

   325

{

   326

   if (eoe->queue_datagram) {

   327

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

   328

       eoe->queue_datagram = 0;

   329

   }

   330

}

   331

   332

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

   333

   334

/** Returns the state of the device.

   335

 *

   336

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

   337

 */

   338

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

   339

{

   340

    return eoe->opened;

   341

}

   342

   343

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

   344

   345

/** Returns the idle state.

   346

 *

   347

 * \retval 1 The device is idle.

   348

 * \retval 0 The device is busy.

   349

 */

   350

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

   351

{

   352

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

   353

}

   354

   355

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

   356

 *  STATE PROCESSING FUNCTIONS

   357

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

   358

   359

/** State: RX_START.

   360

 *

   361

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

   362

 * slave's mailbox for a new EoE datagram.

   363

 */

   364

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

   365

{

   366

    if (eoe->slave->error_flag ||

   367

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

   368

        eoe->rx_idle = 1;

   369

        eoe->tx_idle = 1;

   370

        return;

   371

    }

   372

   373

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

   374

    eoe->queue_datagram = 1;

   375

    eoe->state = ec_eoe_state_rx_check;

   376

}

   377

   378

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

   379

   380

/** State: RX_CHECK.

   381

 *

   382

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

   383

 * datagram, if new data is available.

   384

 */

   385

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

   386

{

   387

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

   388

        eoe->stats.rx_errors++;

   389

#if EOE_DEBUG_LEVEL >= 1

   390

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

   391

                eoe->dev->name);

   392

#endif

   393

        eoe->state = ec_eoe_state_tx_start;

   394

        return;

   395

    }

   396

   397

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

   398

        eoe->rx_idle = 1;

   399

        eoe->state = ec_eoe_state_tx_start;

   400

        return;

   401

    }

   402

   403

    eoe->rx_idle = 0;

   404

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

   405

    eoe->queue_datagram = 1;

   406

    eoe->state = ec_eoe_state_rx_fetch;

   407

}

   408

   409

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

   410

   411

/** State: RX_FETCH.

   412

 *

   413

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

   414

 * datagram.

   415

 */

   416

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

   417

{

   418

    size_t rec_size, data_size;

   419

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

   420

    uint8_t frame_number, fragment_offset, fragment_number;

   421

    off_t offset;

   422

#if EOE_DEBUG_LEVEL >= 3

   423

    unsigned int i;

   424

#endif

   425

   426

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

   427

        eoe->stats.rx_errors++;

   428

#if EOE_DEBUG_LEVEL >= 1

   429

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

   430

                eoe->dev->name);

   431

#endif

   432

        eoe->state = ec_eoe_state_tx_start;

   433

        return;

   434

    }

   435

   436

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

   437

            &mbox_prot, &rec_size);

   438

    if (IS_ERR(data)) {

   439

        eoe->stats.rx_errors++;

   440

#if EOE_DEBUG_LEVEL >= 1

   441

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

   442

                eoe->dev->name);

   443

#endif

   444

        eoe->state = ec_eoe_state_tx_start;

   445

        return;

   446

    }

   447

   448

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

   449

        eoe->stats.rx_errors++;

   450

#if EOE_DEBUG_LEVEL >= 1

   451

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

   452

                eoe->dev->name);

   453

#endif

   454

        eoe->state = ec_eoe_state_tx_start;

   455

        return;

   456

    }

   457

   458

    frame_type = EC_READ_U16(data) & 0x000F;

   459

   460

    if (frame_type != 0x00) {

   461

#if EOE_DEBUG_LEVEL >= 1

   462

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

   463

#endif

   464

        eoe->stats.rx_dropped++;

   465

        eoe->state = ec_eoe_state_tx_start;

   466

        return;

   467

    }

   468

   469

    // EoE Fragment Request received

   470

   471

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

   472

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

   473

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

   474

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

   475

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

   476

   477

#if EOE_DEBUG_LEVEL >= 2

   478

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

   479

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

   480

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

   481

           time_appended ? ", + timestamp" : "",

   482

           time_appended ? rec_size - 8 : rec_size - 4);

   483

#endif

   484

   485

#if EOE_DEBUG_LEVEL >= 3