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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

    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 0

    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 10

    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

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

   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

   120

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

   121

     * like hyphens etc. in interface names. */

   122

    if (slave->sii.alias) {

   123

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   124

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

   125

    } else {

   126

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   127

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

   128

    }

   129

   130

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

   131

   132

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

   133

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

   134

        ret = -ENODEV;

   135

        goto out_return;

   136

    }

   137

   138

    // initialize net_device

   139

    eoe->dev->open = ec_eoedev_open;

   140

    eoe->dev->stop = ec_eoedev_stop;

   141

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   142

    eoe->dev->get_stats = ec_eoedev_stats;

   143

   144

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

   145

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

   146

   147

    // initialize private data

   148

    priv = netdev_priv(eoe->dev);

   149

    *priv = eoe;

   150

   151

    // Usually setting the MTU appropriately makes the upper layers

   152

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

   153

    // 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;

   157

#endif

   158

   159

    // connect the net_device to the kernel

   160

    ret = register_netdev(eoe->dev);

   161

    if (ret) {

   162

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

   163

        goto out_free;

   164

    }

   165

   166

    // make the last address octet unique

   167

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

   168

    return 0;

   169

   170

 out_free:

   171

    free_netdev(eoe->dev);

   172

    eoe->dev = NULL;

   173

 out_return:

   174

    return ret;

   175

}

   176

   177

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

   178

   179

/** EoE destructor.

   180

 *

   181

 * Unregisteres the net_device and frees allocated memory.

   182

 */

   183

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

   184

{

   185

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

   186

    free_netdev(eoe->dev);

   187

   188

    // empty transmit queue

   189

    ec_eoe_flush(eoe);

   190

   191

    if (eoe->tx_frame) {

   192

        dev_kfree_skb(eoe->tx_frame->skb);

   193

        kfree(eoe->tx_frame);

   194

    }

   195

   196

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

   197

   198

    ec_datagram_clear(&eoe->datagram);

   199

}

   200

   201

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

   202

   203

/** Empties the transmit queue.

   204

 */

   205

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

   206

{

   207

    ec_eoe_frame_t *frame, *next;

   208

   209

    spin_lock_bh(&eoe->tx_queue_lock);

   210

   211

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

   212

        list_del(&frame->queue);

   213

        dev_kfree_skb(frame->skb);

   214

        kfree(frame);

   215

    }

   216

    eoe->tx_queued_frames = 0;

   217

   218

    spin_unlock_bh(&eoe->tx_queue_lock);

   219

}

   220

   221

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

   222

   223

/** Sends a frame or the next fragment.

   224

 */

   225

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

   226

{

   227

    size_t remaining_size, current_size, complete_offset;

   228

    unsigned int last_fragment;

   229

    uint8_t *data;

   230

#if EOE_DEBUG_LEVEL >= 3

   231

    unsigned int i;

   232

#endif

   233

   234

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

   235

   236

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

   237

        current_size = remaining_size;

   238

        last_fragment = 1;

   239

    } else {

   240

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

   241

        last_fragment = 0;

   242

    }

   243

   244

    if (eoe->tx_fragment_number) {

   245

        complete_offset = eoe->tx_offset / 32;

   246

    }

   247

    else {

   248

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

   249

        complete_offset = remaining_size / 32 + 1;

   250

    }

   251

   252

#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,

   256

           eoe->tx_queued_frames);

   257

#endif

   258

   259

#if EOE_DEBUG_LEVEL >= 3

   260

    EC_DBG("");

   261

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

   262

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

   263

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

   264

            printk("\n");

   265

            EC_DBG("");

   266

        }

   267

    }

   268

    printk("\n");

   269

#endif

   270

   271

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

   272

            0x02, current_size + 4);

   273

    if (IS_ERR(data))

   274

        return PTR_ERR(data);

   275

   276

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

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    EC_WRITE_U8 (data + 1, last_fragment);

   278

    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));

   281

   282

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

   283

    eoe->queue_datagram = 1;

   284

   285

    eoe->tx_offset += current_size;

   286

    eoe->tx_fragment_number++;

   287

    return 0;

   288

}

   289

   290

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

   291

   292

/** Runs the EoE state machine.

   293

 */

   294

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

   295

{

   296

    if (!eoe->opened)

   297

        return;

   298

   299

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

   300

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

   301

        return;

   302

   303

    // call state function

   304

    eoe->state(eoe);

   305

   306

    // update statistics

   307

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

   308

        eoe->rx_rate = eoe->rx_counter;

   309

        eoe->tx_rate = eoe->tx_counter;

   310

        eoe->rx_counter = 0;

   311

        eoe->tx_counter = 0;

   312

        eoe->rate_jiffies = jiffies;

   313

    }

   314

   315

    ec_datagram_output_stats(&eoe->datagram);

   316

}

   317

   318

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

   319

   320

/** Queues the datagram, if necessary.

   321

 */

   322

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

   323

{

   324

   if (eoe->queue_datagram) {

   325

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

   326

       eoe->queue_datagram = 0;

   327

   }

   328

}

   329

   330

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

   331

   332

/** Returns the state of the device.

   333

 *

   334

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

   335

 */

   336

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

   337

{

   338

    return eoe->opened;

   339

}

   340

   341

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

   342

 *  STATE PROCESSING FUNCTIONS

   343

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

   344

   345

/** State: RX_START.

   346

 *

   347

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

   348

 * slave's mailbox for a new EoE datagram.

   349

 */

   350

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

   351

{

   352

    if (eoe->slave->error_flag || !eoe->slave->master->main_device.link_state)

   353

        return;

   354

   355

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

   356

    eoe->queue_datagram = 1;

   357

    eoe->state = ec_eoe_state_rx_check;

   358

}

   359

   360

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

   361

   362

/** State: RX_CHECK.

   363

 *

   364

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

   365

 * datagram, if new data is available.

   366

 */

   367

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

   368

{

   369

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

   370

        eoe->stats.rx_errors++;

   371

#if EOE_DEBUG_LEVEL >= 1

   372

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

   373

                eoe->dev->name);

   374

#endif

   375

        eoe->state = ec_eoe_state_tx_start;

   376

        return;

   377

    }

   378

   379

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

   380

        eoe->state = ec_eoe_state_tx_start;

   381

        return;

   382

    }

   383

   384

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

   385

    eoe->queue_datagram = 1;

   386

    eoe->state = ec_eoe_state_rx_fetch;

   387

}

   388

   389

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

   390

   391

/** State: RX_FETCH.

   392

 *

   393

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

   394

 * datagram.

   395

 */

   396

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

   397

{

   398

    size_t rec_size, data_size;

   399

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

   400

    uint8_t frame_number, fragment_offset, fragment_number;

   401

    off_t offset;

   402

#if EOE_DEBUG_LEVEL >= 3

   403

    unsigned int i;

   404

#endif

   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 fetch datagram for %s.\n",

   410

                eoe->dev->name);

   411

#endif

   412

        eoe->state = ec_eoe_state_tx_start;

   413

        return;

   414

    }

   415

   416

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

   417

            &mbox_prot, &rec_size);

   418

    if (IS_ERR(data)) {

   419

        eoe->stats.rx_errors++;

   420

#if EOE_DEBUG_LEVEL >= 1

   421

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

   422

                eoe->dev->name);

   423

#endif

   424

        eoe->state = ec_eoe_state_tx_start;

   425

        return;

   426

    }

   427

   428

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

   429

        eoe->stats.rx_errors++;

   430

#if EOE_DEBUG_LEVEL >= 1

   431

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

   432

                eoe->dev->name);

   433

#endif

   434

        eoe->state = ec_eoe_state_tx_start;

   435

        return;

   436

    }

   437

   438

    frame_type = EC_READ_U16(data) & 0x000F;

   439

   440

    if (frame_type != 0x00) {

   441

#if EOE_DEBUG_LEVEL >= 1

   442

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

   443

#endif

   444

        eoe->stats.rx_dropped++;

   445

        eoe->state = ec_eoe_state_tx_start;

   446

        return;

   447

    }

   448

   449

    // EoE Fragment Request received

   450

   451

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

   452

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

   453

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

   454

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

   455

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

   456

   457

#if EOE_DEBUG_LEVEL >= 2

   458

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

   459

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

   460

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

   461

           time_appended ? ", + timestamp" : "",

   462

           time_appended ? rec_size - 8 : rec_size - 4);

   463

#endif

   464

   465

#if EOE_DEBUG_LEVEL >= 3

   466

    EC_DBG("");

   467

    for (i = 0; i < rec_size - 4; i++) {

   468

        printk("%02X ", data[i + 4]);

   469

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

   470

            printk("\n");

   471

            EC_DBG("");

   472

        }

   473

    }

   474

    printk("\n");

   475

#endif

   476

   477

    data_size = time_appended ? rec_size - 8 : rec_size - 4;

   478

   479

    if (!fragment_number) {

   480

        if (eoe->rx_skb) {

   481

            EC_WARN("EoE RX freeing old socket buffer...\n");

   482

            dev_kfree_skb(eoe->rx_skb);

   483

        }

   484

   485

        // new socket buffer

   486