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/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

    49

 *

    50

 * 0 = No debug messages.

    54

 */

    55

#define EOE_DEBUG_LEVEL 0

    56

    59

#define EC_EOE_TX_QUEUE_SIZE 100

    60

    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 *);

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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

/**

    85

 * EoE constructor.

    86

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

    87

 */

    88

    89

int ec_eoe_init(

    90

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

    91

        ec_slave_t *slave /**< EtherCAT slave */

    92

        )

    93

{

    94

    ec_eoe_t **priv;

    95

    int i, ret = 0;

    96

    char name[EC_DATAGRAM_NAME_SIZE];

    97

    98

    eoe->slave = slave;

    99

   100

    ec_datagram_init(&eoe->datagram);

   101

    eoe->queue_datagram = 0;

   102

    eoe->state = ec_eoe_state_rx_start;

   103

    eoe->opened = 0;

   104

    eoe->rx_skb = NULL;

   105

    eoe->rx_expected_fragment = 0;

   106

    INIT_LIST_HEAD(&eoe->tx_queue);

   107

    eoe->tx_frame = NULL;

   108

    eoe->tx_queue_active = 0;

   109

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   110

    eoe->tx_queued_frames = 0;

   111

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

   112

    eoe->tx_frame_number = 0xFF;

   113

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

   114

   115

    eoe->rx_counter = 0;

   116

    eoe->tx_counter = 0;

   117

    eoe->rx_rate = 0;

   118

    eoe->tx_rate = 0;

   119

    eoe->rate_jiffies = 0;

   120

   121

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

   122

     * like hyphens etc. in interface names. */

   123

    if (slave->sii.alias) {

   124

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   125

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

   126

    } else {

   127

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   128

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

   129

    }

   130

   131

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

   132

   133

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

   134

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

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        ret = -ENODEV;

   136

        goto out_return;

   137

    }

   138

   139

    // initialize net_device

   140

    eoe->dev->open = ec_eoedev_open;

   141

    eoe->dev->stop = ec_eoedev_stop;

   142

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

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    eoe->dev->get_stats = ec_eoedev_stats;

   144

   145

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

   146

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

   147

   148

    // initialize private data

   149

    priv = netdev_priv(eoe->dev);

   150

    *priv = eoe;

   151

   152

    // Usually setting the MTU appropriately makes the upper layers

   153

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

   154

    // 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

   157

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

   158

#endif

   159

   160

    // connect the net_device to the kernel

   161

    ret = register_netdev(eoe->dev);

   162

    if (ret) {

   163

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

   164

        goto out_free;

   165

    }

   166

   167

    // make the last address octet unique

   168

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

   169

    return 0;

   170

   171

 out_free:

   172

    free_netdev(eoe->dev);

   173

    eoe->dev = NULL;

   174

 out_return:

   175

    return ret;

   176

}

   177

   178

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

   179

   180

/**

   181

   EoE destructor.

   182

   Unregisteres the net_device and frees allocated memory.

   183

*/

   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

/**

   206

   Empties the transmit queue.

   207

*/

   208

   209

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

   210

{

   211

    ec_eoe_frame_t *frame, *next;

   212

   213

    spin_lock_bh(&eoe->tx_queue_lock);

   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

    spin_unlock_bh(&eoe->tx_queue_lock);

   223

}

   224

   225

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

   226

   227

/**

   228

   Sends a frame or the next fragment.

   229

*/

   230

   231

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

   232

{

   233

    size_t remaining_size, current_size, complete_offset;

   234

    unsigned int last_fragment;

   235

    uint8_t *data;

   237

    unsigned int i;

   238

#endif

   239

   240

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

   241

   242

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

   243

        current_size = remaining_size;

   244

        last_fragment = 1;

   245

    } else {

   246

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

   247

        last_fragment = 0;

   248

    }

   249

   250

    if (eoe->tx_fragment_number) {

   251

        complete_offset = eoe->tx_offset / 32;

   252

    }

   253

    else {

   254

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

   255

        complete_offset = remaining_size / 32 + 1;

   256

    }

   257

   259

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

   260

           " %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);

   263

#endif

   264

   266

    EC_DBG("");

   267

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

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

   269

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

   270

            printk("\n");

   271

            EC_DBG("");

   272

        }

   273

    }

   274

    printk("\n");

   275

#endif

   276

   277

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

   278

            0x02, current_size + 4);

   279

    if (IS_ERR(data))

   280

        return PTR_ERR(data);

   281

   282

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

   283

    EC_WRITE_U8 (data + 1, last_fragment);

   284

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

   285

                            (complete_offset & 0x3F) << 6 |

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

   287

   288

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

   289

    eoe->queue_datagram = 1;

   290

   291

    eoe->tx_offset += current_size;

   292

    eoe->tx_fragment_number++;

   293

    return 0;

   294

}

   295

   296

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

   297

   298

/**

   299

   Runs the EoE state machine.

   300

*/

   301

   302

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

   303

{

   304

    if (!eoe->opened)

   305

        return;

   306

   307

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

   308

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

   309

        return;

   310

   311

    // call state function

   312

    eoe->state(eoe);

   313

   314

    // update statistics

   315

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

   316

        eoe->rx_rate = eoe->rx_counter;

   317

        eoe->tx_rate = eoe->tx_counter;

   318

        eoe->rx_counter = 0;

   319

        eoe->tx_counter = 0;

   320

        eoe->rate_jiffies = jiffies;

   321

    }

   322

   323

    ec_datagram_output_stats(&eoe->datagram);

   324

}

   325

   326

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

   327

   328

/**

   329

 * Queues the datagram, if necessary.

   330

 */

   331

   332

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

   333

{

   334

   if (eoe->queue_datagram) {

   335

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

   336

       eoe->queue_datagram = 0;

   337

   }

   338

}

   339

   340

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

   341

   342

/**

   343

   Returns the state of the device.

   344

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

   345

*/

   346

   347

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

   348

{

   349

    return eoe->opened;

   350

}

   351

   352

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

   353

 *  STATE PROCESSING FUNCTIONS

   354

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

   355

   356

/**

   357

   State: RX_START.

   358

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

   359

   slave's mailbox for a new EoE datagram.

   360

*/

   361

   362

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

   363

{

   364

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

   365

        return;

   366

   367

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

   368

    eoe->queue_datagram = 1;

   369

    eoe->state = ec_eoe_state_rx_check;

   370

}

   371

   372

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

   373

   374

/**

   375

   State: RX_CHECK.

   376

   Processes the checking datagram sent in RX_START and issues a receive

   377

   datagram, if new data is available.

   378

*/

   379

   380

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

   381

{

   382

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

   383

        eoe->stats.rx_errors++;

   388

        eoe->state = ec_eoe_state_tx_start;

   389

        return;

   390

    }

   391

   392

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

   393

        eoe->state = ec_eoe_state_tx_start;

   394

        return;

   395

    }

   396

   397

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

   398

    eoe->queue_datagram = 1;

   399

    eoe->state = ec_eoe_state_rx_fetch;

   400

}

   401

   402

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

   403

   404

/**

   405

   State: RX_FETCH.

   406

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

   407

   EoE datagram.

   408

*/

   409

   410

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

   411

{

   412

    size_t rec_size, data_size;

   413

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

   414

    uint8_t frame_number, fragment_offset, fragment_number;

   415

    off_t offset;

   417

    unsigned int i;

   418

#endif

   419

   420

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

   421

        eoe->stats.rx_errors++;

   426

        eoe->state = ec_eoe_state_tx_start;

   427

        return;

   428

    }

   429

   430

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

   431

            &mbox_prot, &rec_size);

   432

    if (IS_ERR(data)) {

   433

        eoe->stats.rx_errors++;

   438

        eoe->state = ec_eoe_state_tx_start;

   439

        return;

   440

    }

   441

   442

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

   443

        eoe->stats.rx_errors++;

   448

        eoe->state = ec_eoe_state_tx_start;

   449

        return;

   450

    }

   451

   452

    frame_type = EC_READ_U16(data) & 0x000F;

   453

   454

    if (frame_type != 0x00) {

   457

#endif

   458

        eoe->stats.rx_dropped++;

   459

        eoe->state = ec_eoe_state_tx_start;

   460

        return;

   461

    }

   462

   463

    // EoE Fragment Request received

   464

   465

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

   466

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

   467

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

   468

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

   469

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

   470

   472

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

   473

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

   474

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

   475

           time_appended ? ", + timestamp" : "",

   476

           time_appended ? rec_size - 8 : rec_size - 4);

   477

#endif

   478

   480

    EC_DBG("");

   481

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

   482

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

   483

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

   484

            printk("\n");

   485

            EC_DBG("");