1

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

     2

 *

     3

 *  $Id$

     4

 *

     5

 *  Copyright (C) 2006  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

    10

 *  and/or modify it under the terms of the GNU General Public License

    11

 *  as published by the Free Software Foundation; either version 2 of the

    12

 *  License, or (at your option) any later version.

    13

 *

    14

 *  The IgH EtherCAT Master is distributed in the hope that it will be

    15

 *  useful, but WITHOUT ANY WARRANTY; without even the implied warranty of

    16

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    17

 *  GNU General Public License for more details.

    18

 *

    19

 *  You should have received a copy of the GNU General Public License

    20

 *  along with the IgH EtherCAT Master; if not, write to the Free Software

    21

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    22

 *

    23

 *  The right to use EtherCAT Technology is granted and comes free of

    24

 *  charge under condition of compatibility of product made by

    25

 *  Licensee. People intending to distribute/sell products based on the

    26

 *  code, have to sign an agreement to guarantee that products using

    27

 *  software based on IgH EtherCAT master stay compatible with the actual

    28

 *  EtherCAT specification (which are released themselves as an open

    29

 *  standard) as the (only) precondition to have the right to use EtherCAT

    30

 *  Technology, IP and trade marks.

    31

 *

    32

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

    33

    34

/**

    35

   \file

    36

   Ethernet-over-EtherCAT (EoE).

    37

*/

    38

    39

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

    40

    41

#include <linux/netdevice.h>

    42

#include <linux/etherdevice.h>

    43

    44

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

    45

#include "globals.h"

    46

#include "master.h"

    47

#include "slave.h"

    48

#include "mailbox.h"

    49

#include "ethernet.h"

    50

    51

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

    52

    53

/**

    54

 * Defines the debug level of EoE processing.

    55

 *

    56

 * 0 = No debug messages.

    57

 * 1 = Output actions.

    58

 * 2 = Output actions and frame data.

    59

 */

    60

    61

#define EOE_DEBUG_LEVEL 0

    62

    63

/** size of the EoE tx queue */

    64

#define EC_EOE_TX_QUEUE_SIZE 100

    65

    66

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

    67

    68

void ec_eoe_flush(ec_eoe_t *);

    69

    70

// state functions

    71

void ec_eoe_state_rx_start(ec_eoe_t *);

    72

void ec_eoe_state_rx_check(ec_eoe_t *);

    73

void ec_eoe_state_rx_fetch(ec_eoe_t *);

    74

void ec_eoe_state_tx_start(ec_eoe_t *);

    75

void ec_eoe_state_tx_sent(ec_eoe_t *);

    76

    77

// net_device functions

    78

int ec_eoedev_open(struct net_device *);

    79

int ec_eoedev_stop(struct net_device *);

    80

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

    81

struct net_device_stats *ec_eoedev_stats(struct net_device *);

    82

    83

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

    84

    85

/**

    86

 * EoE constructor.

    87

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

    88

 */

    89

    90

int ec_eoe_init(

    91

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

    92

        ec_slave_t *slave /**< EtherCAT slave */

    93

        )

    94

{

    95

    ec_eoe_t **priv;

    96

    int result, i;

    97

    char name[EC_DATAGRAM_NAME_SIZE];

    98

    99

    eoe->slave = slave;

   100

   101

    ec_datagram_init(&eoe->datagram);

   102

    eoe->queue_datagram = 0;

   103

    eoe->state = ec_eoe_state_rx_start;

   104

    eoe->opened = 0;

   105

    eoe->rx_skb = NULL;

   106

    eoe->rx_expected_fragment = 0;

   107

    INIT_LIST_HEAD(&eoe->tx_queue);

   108

    eoe->tx_frame = NULL;

   109

    eoe->tx_queue_active = 0;

   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);

   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

   154

    // is done "manually".

   155

#if 0

   156

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

   157

#endif

   158

   159

    // connect the net_device to the kernel

   160

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

   161

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

   162

        goto out_free;

   163

    }

   164

   165

    // make the last address octet unique

   166

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

   167

    return 0;

   168

   169

 out_free:

   170

    free_netdev(eoe->dev);

   171

    eoe->dev = NULL;

   172

 out_return:

   173

    return -1;

   174

}

   175

   176

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

   177

   178

/**

   179

   EoE destructor.

   180

   Unregisteres the net_device and frees allocated memory.

   181

*/

   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

/**

   204

   Empties the transmit queue.

   205

*/

   206

   207

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

   208

{

   209

    ec_eoe_frame_t *frame, *next;

   210

   211

    spin_lock_bh(&eoe->tx_queue_lock);

   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

    spin_unlock_bh(&eoe->tx_queue_lock);

   221

}

   222

   223

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

   224

   225

/**

   226

   Sends a frame or the next fragment.

   227

*/

   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;

   234

#if EOE_DEBUG_LEVEL > 1

   235

    unsigned int i;

   236

#endif

   237

   238

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

   239

   240

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

   241

        current_size = remaining_size;

   242

        last_fragment = 1;

   243

    }

   244

    else {

   245

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

   246

        last_fragment = 0;

   247

    }

   248

   249

    if (eoe->tx_fragment_number) {

   250

        complete_offset = eoe->tx_offset / 32;

   251

    }

   252

    else {

   253

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

   254

        complete_offset = remaining_size / 32 + 1;

   255

    }

   256

   257

#if EOE_DEBUG_LEVEL > 0

   258

    EC_DBG("EoE TX sending %sfragment %i with %i octets (%i)."

   259

           " %i frames queued.\n", last_fragment ? "last " : "",

   260

           eoe->tx_fragment_number, current_size, complete_offset,

   261

           eoe->tx_queued_frames);

   262

#endif

   263

   264

#if EOE_DEBUG_LEVEL > 1

   265

    EC_DBG("");

   266

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

   267

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

   268

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

   269

            printk("\n");

   270

            EC_DBG("");

   271

        }

   272

    }

   273

    printk("\n");

   274

#endif

   275

   276

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

   277

                                            0x02, current_size + 4)))

   278

        return -1;

   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 |

   284

                            (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;

   290

    eoe->tx_fragment_number++;

   291

    return 0;

   292

}

   293

   294

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

   295

   296

/**

   297

   Runs the EoE state machine.

   298

*/

   299

   300

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

   301

{

   302

    if (!eoe->opened) return;

   303

   304

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

   305

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

   306

        return;

   307

   308

    // call state function

   309

    eoe->state(eoe);

   310

   311

    // update statistics

   312

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

   313

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

   314

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

   315

        eoe->rx_counter = 0;

   316

        eoe->tx_counter = 0;

   317

        eoe->rate_jiffies = jiffies;

   318

    }

   319

   320

    ec_datagram_output_stats(&eoe->datagram);

   321

}

   322

   323

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

   324

   325

/**

   326

 * Queues the datagram, if necessary.

   327

 */

   328

   329

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

   330

{

   331

   if (eoe->queue_datagram) {

   332

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

   333

       eoe->queue_datagram = 0;

   334

   }

   335

}

   336

   337

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

   338

   339

/**

   340

   Returns the state of the device.

   341

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

   342

*/

   343

   344

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

   345

{

   346

    return eoe->opened;

   347

}

   348

   349

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

   350

 *  STATE PROCESSING FUNCTIONS

   351

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

   352

   353

/**

   354

   State: RX_START.

   355

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

   356

   slave's mailbox for a new EoE datagram.

   357

*/

   358

   359

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

   360

{

   361

    if (eoe->slave->online_state == EC_SLAVE_OFFLINE ||

   362

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

   363

        return;

   364

   365

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

   366

    eoe->queue_datagram = 1;

   367

    eoe->state = ec_eoe_state_rx_check;

   368

}

   369

   370

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

   371

   372

/**

   373

   State: RX_CHECK.

   374

   Processes the checking datagram sent in RX_START and issues a receive

   375

   datagram, if new data is available.

   376

*/

   377

   378

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

   379

{

   380

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

   381

        eoe->stats.rx_errors++;

   382

        eoe->state = ec_eoe_state_tx_start;

   383

        return;

   384

    }

   385

   386

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

   387

        eoe->state = ec_eoe_state_tx_start;

   388

        return;

   389

    }

   390

   391

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

   392

    eoe->queue_datagram = 1;

   393

    eoe->state = ec_eoe_state_rx_fetch;

   394

}

   395

   396

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

   397

   398

/**

   399

   State: RX_FETCH.

   400

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

   401

   EoE datagram.

   402

*/

   403

   404

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

   405

{

   406

    size_t rec_size, data_size;

   407

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

   408

    uint8_t frame_number, fragment_offset, fragment_number;

   409

    off_t offset;

   410

#if EOE_DEBUG_LEVEL > 1

   411

    unsigned int i;

   412

#endif

   413

   414

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

   415

        eoe->stats.rx_errors++;

   416

        eoe->state = ec_eoe_state_tx_start;

   417

        return;

   418

    }

   419

   420

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

   421

                                     &mbox_prot, &rec_size))) {

   422

        eoe->stats.rx_errors++;

   423

        eoe->state = ec_eoe_state_tx_start;

   424

        return;

   425

    }

   426

   427

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

   428

        eoe->stats.rx_errors++;

   429

        eoe->state = ec_eoe_state_tx_start;

   430

        return;

   431

    }

   432

   433

    frame_type = EC_READ_U16(data) & 0x000F;

   434

   435

    if (frame_type != 0x00) {

   436

#if EOE_DEBUG_LEVEL > 0

   437

        EC_DBG("other frame received.\n");

   438

#endif

   439

        eoe->stats.rx_dropped++;

   440

        eoe->state = ec_eoe_state_tx_start;

   441

        return;

   442

    }

   443

   444

    // EoE Fragment Request received

   445

   446

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

   447

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

   448

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

   449

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

   450

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

   451

   452

#if EOE_DEBUG_LEVEL > 0

   453

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

   454

           " %i octets\n", fragment_number, fragment_offset,

   455

           frame_number,

   456

           last_fragment ? ", last fragment" : "",

   457

           time_appended ? ", + timestamp" : "",

   458

           time_appended ? rec_size - 8 : rec_size - 4);

   459

#endif

   460

   461

#if EOE_DEBUG_LEVEL > 1

   462

    EC_DBG("");

   463

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

   464

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

   465

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

   466

            printk("\n");

   467

            EC_DBG("");

   468

        }

   469

    }

   470

    printk("\n");

   471

#endif

   472

   473

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

   474

   475

    if (!fragment_number) {

   476

        if (eoe->rx_skb) {

   477

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

   478

            dev_kfree_skb(eoe->rx_skb);

   479

        }

   480

   481

        // new socket buffer

   482

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

   483

            if (printk_ratelimit())

   484

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

   485

            eoe->stats.rx_dropped++;

   486

            eoe->state = ec_eoe_state_tx_start;

   487

            return;

   488

        }

   489