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

    11

 *  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

 *  Using the EtherCAT technology and brand is permitted in compliance with

    23

 *  the industrial property and similar rights of Beckhoff Automation GmbH.

    24

 *

    25

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

    26

    27

/**

    28

   \file

    29

   Ethernet over EtherCAT (EoE).

    30

*/

    31

    32

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

    33

    34

#include <linux/netdevice.h>

    35

#include <linux/etherdevice.h>

    36

    37

#include "../include/ecrt.h"

    38

#include "globals.h"

    39

#include "master.h"

    40

#include "slave.h"

    41

#include "mailbox.h"

    42

#include "ethernet.h"

    43

    44

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

    45

    46

/**

    47

 * Defines the debug level of EoE processing.

    48

 *

    49

 * 0 = No debug messages.

    50

 * 1 = Output actions.

    51

 * 2 = Output actions and frame data.

    52

 */

    53

    54

#define EOE_DEBUG_LEVEL 0

    55

    56

/** size of the EoE tx queue */

    57

#define EC_EOE_TX_QUEUE_SIZE 100

    58

    59

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

    60

    61

void ec_eoe_flush(ec_eoe_t *);

    62

    63

// state functions

    64

void ec_eoe_state_rx_start(ec_eoe_t *);

    65

void ec_eoe_state_rx_check(ec_eoe_t *);

    66

void ec_eoe_state_rx_fetch(ec_eoe_t *);

    67

void ec_eoe_state_tx_start(ec_eoe_t *);

    68

void ec_eoe_state_tx_sent(ec_eoe_t *);

    69

    70

// net_device functions

    71

int ec_eoedev_open(struct net_device *);

    72

int ec_eoedev_stop(struct net_device *);

    73

int ec_eoedev_tx(struct sk_buff *, struct net_device *);

    74

struct net_device_stats *ec_eoedev_stats(struct net_device *);

    75

    76

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

    77

    78

/**

    79

 * EoE constructor.

    80

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

    81

 */

    82

    83

int ec_eoe_init(

    84

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

    85

        ec_slave_t *slave /**< EtherCAT slave */

    86

        )

    87

{

    88

    ec_eoe_t **priv;

    89

    int result, i;

    90

    char name[EC_DATAGRAM_NAME_SIZE];

    91

    92

    eoe->slave = slave;

    93

    94

    ec_datagram_init(&eoe->datagram);

    95

    eoe->queue_datagram = 0;

    96

    eoe->state = ec_eoe_state_rx_start;

    97

    eoe->opened = 0;

    98

    eoe->rx_skb = NULL;

    99

    eoe->rx_expected_fragment = 0;

   100

    INIT_LIST_HEAD(&eoe->tx_queue);

   101

    eoe->tx_frame = NULL;

   102

    eoe->tx_queue_active = 0;

   103

    eoe->tx_queued_frames = 0;

   104

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

   105

    eoe->tx_frame_number = 0xFF;

   106

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

   107

   108

    eoe->rx_counter = 0;

   109

    eoe->tx_counter = 0;

   110

    eoe->rx_rate = 0;

   111

    eoe->tx_rate = 0;

   112

    eoe->rate_jiffies = 0;

   113

   114

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

   115

     * like hyphens etc. in interface names. */

   116

    if (slave->sii.alias) {

   117

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   118

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

   119

    } else {

   120

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   121

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

   122

    }

   123

   124

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

   125

   126

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

   127

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

   128

        goto out_return;

   129

    }

   130

   131

    // initialize net_device

   132

    eoe->dev->open = ec_eoedev_open;

   133

    eoe->dev->stop = ec_eoedev_stop;

   134

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   135

    eoe->dev->get_stats = ec_eoedev_stats;

   136

   137

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

   138

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

   139

   140

    // initialize private data

   141

    priv = netdev_priv(eoe->dev);

   142

    *priv = eoe;

   143

   144

    // Usually setting the MTU appropriately makes the upper layers

   145

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

   146

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

   147

    // is done "manually".

   148

#if 0

   149

    eoe->dev->mtu = slave->sii.rx_mailbox_size - ETH_HLEN - 10;

   150

#endif

   151

   152

    // connect the net_device to the kernel

   153

    if ((result = register_netdev(eoe->dev))) {

   154

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

   155

        goto out_free;

   156

    }

   157

   158

    // make the last address octet unique

   159

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

   160

    return 0;

   161

   162

 out_free:

   163

    free_netdev(eoe->dev);

   164

    eoe->dev = NULL;

   165

 out_return:

   166

    return -1;

   167

}

   168

   169

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

   170

   171

/**

   172

   EoE destructor.

   173

   Unregisteres the net_device and frees allocated memory.

   174

*/

   175

   176

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

   177

{

   178

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

   179

    free_netdev(eoe->dev);

   180

   181

    // empty transmit queue

   182

    ec_eoe_flush(eoe);

   183

   184

    if (eoe->tx_frame) {

   185

        dev_kfree_skb(eoe->tx_frame->skb);

   186

        kfree(eoe->tx_frame);

   187

    }

   188

   189

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

   190

   191

    ec_datagram_clear(&eoe->datagram);

   192

}

   193

   194

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

   195

   196

/**

   197

   Empties the transmit queue.

   198

*/

   199

   200

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

   201

{

   202

    ec_eoe_frame_t *frame, *next;

   203

   204

    spin_lock_bh(&eoe->tx_queue_lock);

   205

   206

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

   207

        list_del(&frame->queue);

   208

        dev_kfree_skb(frame->skb);

   209

        kfree(frame);

   210

    }

   211

    eoe->tx_queued_frames = 0;

   212

   213

    spin_unlock_bh(&eoe->tx_queue_lock);

   214

}

   215

   216

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

   217

   218

/**

   219

   Sends a frame or the next fragment.

   220

*/

   221

   222

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

   223

{

   224

    size_t remaining_size, current_size, complete_offset;

   225

    unsigned int last_fragment;

   226

    uint8_t *data;

   227

#if EOE_DEBUG_LEVEL > 1

   228

    unsigned int i;

   229

#endif

   230

   231

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

   232

   233

    if (remaining_size <= eoe->slave->sii.tx_mailbox_size - 10) {

   234

        current_size = remaining_size;

   235

        last_fragment = 1;

   236

    }

   237

    else {

   238

        current_size = ((eoe->slave->sii.tx_mailbox_size - 10) / 32) * 32;

   239

        last_fragment = 0;

   240

    }

   241

   242

    if (eoe->tx_fragment_number) {

   243

        complete_offset = eoe->tx_offset / 32;

   244

    }

   245

    else {

   246

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

   247

        complete_offset = remaining_size / 32 + 1;

   248

    }

   249

   250

#if EOE_DEBUG_LEVEL > 0

   251

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

   252

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

   253

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

   254

           eoe->tx_queued_frames);

   255

#endif

   256

   257

#if EOE_DEBUG_LEVEL > 1

   258

    EC_INFO("");

   259

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

   260

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

   261

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

   262

            printk("\n");

   263

            EC_INFO("");

   264

        }

   265

    }

   266

    printk("\n");

   267

#endif

   268

   269

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

   270

                                            0x02, current_size + 4)))

   271

        return -1;

   272

   273

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

   274

    EC_WRITE_U8 (data + 1, last_fragment);

   275

    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));

   278

   279

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

   280

    eoe->queue_datagram = 1;

   281

   282

    eoe->tx_offset += current_size;

   283

    eoe->tx_fragment_number++;

   284

    return 0;

   285

}

   286

   287

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

   288

   289

/**

   290

   Runs the EoE state machine.

   291

*/

   292

   293

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

   294

{

   295

    if (!eoe->opened) return;

   296

   297

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

   298

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

   299

        return;

   300

   301

    // call state function

   302

    eoe->state(eoe);

   303

   304

    // update statistics

   305

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

   306

        eoe->rx_rate = eoe->rx_counter * 8;

   307

        eoe->tx_rate = eoe->tx_counter * 8;

   308

        eoe->rx_counter = 0;

   309

        eoe->tx_counter = 0;

   310

        eoe->rate_jiffies = jiffies;

   311

    }

   312

   313

    ec_datagram_output_stats(&eoe->datagram);

   314

}

   315

   316

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

   317

   318

/**

   319

 * Queues the datagram, if necessary.

   320

 */

   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

/**

   333

   Returns the state of the device.

   334

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

   335

*/

   336

   337

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

   338

{

   339

    return eoe->opened;

   340

}

   341

   342

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

   343

 *  STATE PROCESSING FUNCTIONS

   344

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

   345

   346

/**

   347

   State: RX_START.

   348

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

   349

   slave's mailbox for a new EoE datagram.

   350

*/

   351

   352

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

   353

{

   354

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

   355

        return;

   356

   357

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

   358

    eoe->queue_datagram = 1;

   359

    eoe->state = ec_eoe_state_rx_check;

   360

}

   361

   362

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

   363

   364

/**

   365

   State: RX_CHECK.

   366

   Processes the checking datagram sent in RX_START and issues a receive

   367

   datagram, if new data is available.

   368

*/

   369

   370

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

   371

{

   372

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

   373

        eoe->stats.rx_errors++;

   374

        eoe->state = ec_eoe_state_tx_start;

   375

        return;

   376

    }

   377

   378

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

   379

        eoe->state = ec_eoe_state_tx_start;

   380

        return;

   381

    }

   382

   383

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

   384

    eoe->queue_datagram = 1;

   385

    eoe->state = ec_eoe_state_rx_fetch;

   386

}

   387

   388

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

   389

   390

/**

   391

   State: RX_FETCH.

   392

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

   393

   EoE datagram.

   394

*/

   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 > 1

   403

    unsigned int i;

   404

#endif

   405

   406

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

   407

        eoe->stats.rx_errors++;

   408

        eoe->state = ec_eoe_state_tx_start;

   409

        return;

   410

    }

   411

   412

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

   413

                                     &mbox_prot, &rec_size))) {

   414

        eoe->stats.rx_errors++;

   415

        eoe->state = ec_eoe_state_tx_start;

   416

        return;

   417

    }

   418

   419

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

   420

        eoe->stats.rx_errors++;

   421

        eoe->state = ec_eoe_state_tx_start;

   422

        return;

   423

    }

   424

   425

    frame_type = EC_READ_U16(data) & 0x000F;

   426

   427

    if (frame_type != 0x00) {

   428

#if EOE_DEBUG_LEVEL > 0

   429

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

   430

#endif

   431

        eoe->stats.rx_dropped++;

   432

        eoe->state = ec_eoe_state_tx_start;

   433

        return;

   434

    }

   435

   436

    // EoE Fragment Request received

   437

   438

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

   439

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

   440

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

   441

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

   442

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

   443

   444

#if EOE_DEBUG_LEVEL > 0

   445

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

   446

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

   447

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

   448

           time_appended ? ", + timestamp" : "",

   449

           time_appended ? rec_size - 8 : rec_size - 4);

   450

#endif

   451

   452

#if EOE_DEBUG_LEVEL > 1

   453

    EC_INFO("");

   454

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

   455

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

   456

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

   457

            printk("\n");

   458

            EC_INFO("");

   459

        }

   460

    }

   461

    printk("\n");

   462

#endif

   463

   464

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

   465

   466

    if (!fragment_number) {

   467

        if (eoe->rx_skb) {

   468

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

   469

            dev_kfree_skb(eoe->rx_skb);

   470

        }

   471

   472

        // new socket buffer

   473

        if (!(eoe->rx_skb = dev_alloc_skb(fragment_offset * 32))) {

   474

            if (printk_ratelimit())

   475

                EC_WARN("EoE RX low on mem. frame dropped.\n");

   476

            eoe->stats.rx_dropped++;

   477

            eoe->state = ec_eoe_state_tx_start;

   478

            return;

   479

        }

   480

   481

        eoe->rx_skb_offset = 0;

   482

        eoe->rx_skb_size = fragment_offset * 32;

   483

        eoe->rx_expected_fragment = 0;

   484

    }

   485

    else {

   486

        if (!eoe->rx_skb) {

   487

            eoe->stats.rx_dropped++;