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

     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 registeres it.

    88

*/

    89

    90

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

    91

{

    92

    ec_eoe_t **priv;

    93

    int result, i;

    94

    95

    eoe->slave = NULL;

    96

    ec_datagram_init(&eoe->datagram);

    97

    eoe->state = ec_eoe_state_rx_start;

    98

    eoe->opened = 0;

    99

    eoe->rx_skb = NULL;

   100

    eoe->rx_expected_fragment = 0;

   101

    INIT_LIST_HEAD(&eoe->tx_queue);

   102

    eoe->tx_frame = NULL;

   103

    eoe->tx_queue_active = 0;

   104

    eoe->tx_queued_frames = 0;

   105

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

   106

    eoe->tx_frame_number = 0xFF;

   107

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

   108

   109

    eoe->rx_counter = 0;

   110

    eoe->tx_counter = 0;

   111

    eoe->rx_rate = 0;

   112

    eoe->tx_rate = 0;

   113

    eoe->rate_jiffies = 0;

   114

   115

    if (!(eoe->dev =

   116

          alloc_netdev(sizeof(ec_eoe_t *), "eoe%d", ether_setup))) {

   117

        EC_ERR("Unable to allocate net_device for EoE handler!\n");

   118

        goto out_return;

   119

    }

   120

   121

    // initialize net_device

   122

    eoe->dev->open = ec_eoedev_open;

   123

    eoe->dev->stop = ec_eoedev_stop;

   124

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   125

    eoe->dev->get_stats = ec_eoedev_stats;

   126

   127

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

   128

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

   129

   130

    // initialize private data

   131

    priv = netdev_priv(eoe->dev);

   132

    *priv = eoe;

   133

   134

    // Usually setting the MTU appropriately makes the upper layers

   135

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

   136

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

   137

    // is done "manually".

   138

#if 0

   139

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

   140

#endif

   141

   142

    // connect the net_device to the kernel

   143

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

   144

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

   145

        goto out_free;

   146

    }

   147

   148

    // make the last address octet unique

   149

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

   150

   151

    return 0;

   152

   153

 out_free:

   154

    free_netdev(eoe->dev);

   155

    eoe->dev = NULL;

   156

 out_return:

   157

    return -1;

   158

}

   159

   160

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

   161

   162

/**

   163

   EoE destructor.

   164

   Unregisteres the net_device and frees allocated memory.

   165

*/

   166

   167

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

   168

{

   169

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

   170

    free_netdev(eoe->dev);

   171

   172

    // empty transmit queue

   173

    ec_eoe_flush(eoe);

   174

   175

    if (eoe->tx_frame) {

   176

        dev_kfree_skb(eoe->tx_frame->skb);

   177

        kfree(eoe->tx_frame);

   178

    }

   179

   180

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

   181

   182

    ec_datagram_clear(&eoe->datagram);

   183

}

   184

   185

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

   186

   187

/**

   188

   Empties the transmit queue.

   189

*/

   190

   191

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

   192

{

   193

    ec_eoe_frame_t *frame, *next;

   194

   195

    spin_lock_bh(&eoe->tx_queue_lock);

   196

   197

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

   198

        list_del(&frame->queue);

   199

        dev_kfree_skb(frame->skb);

   200

        kfree(frame);

   201

    }

   202

    eoe->tx_queued_frames = 0;

   203

   204

    spin_unlock_bh(&eoe->tx_queue_lock);

   205

}

   206

   207

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

   208

   209

/**

   210

   Sends a frame or the next fragment.

   211

*/

   212

   213

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

   214

{

   215

    size_t remaining_size, current_size, complete_offset;

   216

    unsigned int last_fragment;

   217

    uint8_t *data;

   218

#if EOE_DEBUG_LEVEL > 1

   219

    unsigned int i;

   220

#endif

   221

   222

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

   223

   224

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

   225

        current_size = remaining_size;

   226

        last_fragment = 1;

   227

    }

   228

    else {

   229

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

   230

        last_fragment = 0;

   231

    }

   232

   233

    if (eoe->tx_fragment_number) {

   234

        complete_offset = eoe->tx_offset / 32;

   235

    }

   236

    else {

   237

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

   238

        complete_offset = remaining_size / 32 + 1;

   239

    }

   240

   241

#if EOE_DEBUG_LEVEL > 0

   242

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

   243

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

   244

           eoe->tx_fragment_number, current_size, complete_offset,

   245

           eoe->tx_queued_frames);

   246

#endif

   247

   248

#if EOE_DEBUG_LEVEL > 1

   249

    EC_DBG("");

   250

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

   251

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

   252

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

   253

            printk("\n");

   254

            EC_DBG("");

   255

        }

   256

    }

   257

    printk("\n");

   258

#endif

   259

   260

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

   261

                                            0x02, current_size + 4)))

   262

        return -1;

   263

   264

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

   265

    EC_WRITE_U8 (data + 1, last_fragment);

   266

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

   267

                            (complete_offset & 0x3F) << 6 |

   268

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

   269

   270

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

   271

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

   272

   273

    eoe->tx_offset += current_size;

   274

    eoe->tx_fragment_number++;

   275

    return 0;

   276

}

   277

   278

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

   279

   280

/**

   281

   Runs the EoE state machine.

   282

*/

   283

   284

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

   285

{

   286

    if (!eoe->opened) return;

   287

   288

    // call state function

   289

    eoe->state(eoe);

   290

   291

    // update statistics

   292

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

   293

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

   294

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

   295

        eoe->rx_counter = 0;

   296

        eoe->tx_counter = 0;

   297

        eoe->rate_jiffies = jiffies;

   298

    }

   299

}

   300

   301

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

   302

   303

/**

   304

   Returns the state of the device.

   305

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

   306

*/

   307

   308

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

   309

{

   310

    return eoe->slave && eoe->opened;

   311

}

   312

   313

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

   314

 *  STATE PROCESSING FUNCTIONS

   315

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

   316

   317

/**

   318

   State: RX_START.

   319

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

   320

   slave's mailbox for a new EoE datagram.

   321

*/

   322

   323

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

   324

{

   325

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

   326

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

   327

        return;

   328

   329

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

   330

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

   331

    eoe->state = ec_eoe_state_rx_check;

   332

}

   333

   334

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

   335

   336

/**

   337

   State: RX_CHECK.

   338

   Processes the checking datagram sent in RX_START and issues a receive

   339

   datagram, if new data is available.

   340

*/

   341

   342

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

   343

{

   344

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

   345

        eoe->stats.rx_errors++;

   346

        eoe->state = ec_eoe_state_tx_start;

   347

        return;

   348

    }

   349

   350

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

   351

        eoe->state = ec_eoe_state_tx_start;

   352

        return;

   353

    }

   354

   355

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

   356

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

   357

    eoe->state = ec_eoe_state_rx_fetch;

   358

}

   359

   360

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

   361

   362

/**

   363

   State: RX_FETCH.

   364

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

   365

   EoE datagram.

   366

*/

   367

   368

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

   369

{

   370

    size_t rec_size, data_size;

   371

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

   372

    uint8_t frame_number, fragment_offset, fragment_number;

   373

    off_t offset;

   374

#if EOE_DEBUG_LEVEL > 1

   375

    unsigned int i;

   376

#endif

   377

   378

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

   379

        eoe->stats.rx_errors++;

   380

        eoe->state = ec_eoe_state_tx_start;

   381

        return;

   382

    }

   383

   384

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

   385

                                     &mbox_prot, &rec_size))) {

   386

        eoe->stats.rx_errors++;

   387

        eoe->state = ec_eoe_state_tx_start;

   388

        return;

   389

    }

   390

   391

    if (mbox_prot != 0x02) { // EoE

   392

        eoe->stats.rx_errors++;

   393

        eoe->state = ec_eoe_state_tx_start;

   394

        return;

   395

    }

   396

   397

    frame_type = EC_READ_U16(data) & 0x000F;

   398

   399

    if (frame_type != 0x00) {

   400

#if EOE_DEBUG_LEVEL > 0

   401

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

   402

#endif

   403

        eoe->stats.rx_dropped++;

   404

        eoe->state = ec_eoe_state_tx_start;

   405

        return;

   406

    }

   407

   408

    // EoE Fragment Request received

   409

   410

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

   411

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

   412

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

   413

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

   414

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

   415

   416

#if EOE_DEBUG_LEVEL > 0

   417

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

   418

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

   419

           frame_number,

   420

           last_fragment ? ", last fragment" : "",

   421

           time_appended ? ", + timestamp" : "",

   422

           time_appended ? rec_size - 8 : rec_size - 4);

   423

#endif

   424

   425

#if EOE_DEBUG_LEVEL > 1

   426

    EC_DBG("");

   427

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

   428

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

   429

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

   430

            printk("\n");

   431

            EC_DBG("");

   432

        }

   433

    }

   434

    printk("\n");

   435

#endif

   436

   437

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

   438

   439

    if (!fragment_number) {

   440

        if (eoe->rx_skb) {

   441

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

   442

            dev_kfree_skb(eoe->rx_skb);

   443

        }

   444

   445

        // new socket buffer

   446

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

   447

            if (printk_ratelimit())

   448

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

   449

            eoe->stats.rx_dropped++;

   450

            eoe->state = ec_eoe_state_tx_start;

   451

            return;

   452

        }

   453

   454

        eoe->rx_skb_offset = 0;

   455

        eoe->rx_skb_size = fragment_offset * 32;

   456

        eoe->rx_expected_fragment = 0;

   457

    }

   458

    else {

   459

        if (!eoe->rx_skb) {

   460

            eoe->stats.rx_dropped++;

   461

            eoe->state = ec_eoe_state_tx_start;

   462

            return;

   463

        }

   464

   465

        offset = fragment_offset * 32;

   466

        if (offset != eoe->rx_skb_offset ||

   467

            offset + data_size > eoe->rx_skb_size ||

   468

            fragment_number != eoe->rx_expected_fragment) {

   469

            dev_kfree_skb(eoe->rx_skb);

   470

            eoe->rx_skb = NULL;

   471

            eoe->stats.rx_errors++;

   472

            eoe->state = ec_eoe_state_tx_start;

   473

            return;

   474

        }

   475

    }

   476

   477

    // copy fragment into socket buffer

   478

    memcpy(skb_put(eoe->rx_skb, data_size), data + 4, data_size);

   479

    eoe->rx_skb_offset += data_size;

   480

   481

    if (last_fragment) {

   482

        // update statistics

   483

        eoe->stats.rx_packets++;

   484

        eoe->stats.rx_bytes += eoe->rx_skb->len;

   485

        eoe->rx_counter += eoe->rx_skb->len;

   486

   487

#if EOE_DEBUG_LEVEL > 0

   488

        EC_DBG("EoE RX frame completed with %u octets.\n",

   489

               eoe->rx_skb->len);