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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

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 *  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

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 *  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/etherdevice.h>

    42

    43

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

    44

#include "globals.h"

    45

#include "master.h"

    46

#include "slave.h"

    47

#include "mailbox.h"

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#include "ethernet.h"

    49

    50

#define EOE_DEBUG_LEVEL 0

    51

    52

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

    53

    54

void ec_eoe_flush(ec_eoe_t *);

    55

    56

// state functions

    57

void ec_eoe_state_rx_start(ec_eoe_t *);

    58

void ec_eoe_state_rx_check(ec_eoe_t *);

    59

void ec_eoe_state_rx_fetch(ec_eoe_t *);

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void ec_eoe_state_tx_start(ec_eoe_t *);

    61

void ec_eoe_state_tx_sent(ec_eoe_t *);

    62

    63

// net_device functions

    64

int ec_eoedev_open(struct net_device *);

    65

int ec_eoedev_stop(struct net_device *);

    66

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

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struct net_device_stats *ec_eoedev_stats(struct net_device *);

    68

    69

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

    70

    71

/**

    72

   EoE constructor.

    73

   Initializes the EoE handler, creates a net_device and registeres it.

    74

*/

    75

    76

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

    77

{

    78

    ec_eoe_t **priv;

    79

    int result, i;

    80

    81

    eoe->slave = NULL;

    83

    eoe->state = ec_eoe_state_rx_start;

    84

    eoe->opened = 0;

    85

    eoe->rx_skb = NULL;

    86

    eoe->rx_expected_fragment = 0;

    87

    INIT_LIST_HEAD(&eoe->tx_queue);

    88

    eoe->tx_frame = NULL;

    89

    eoe->tx_queue_active = 0;

    90

    eoe->tx_queued_frames = 0;

    91

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

    92

    eoe->tx_frame_number = 0xFF;

    93

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

    94

    95

    if (!(eoe->dev =

    96

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

    97

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

    98

        goto out_return;

    99

    }

   100

   101

    // initialize net_device

   102

    eoe->dev->open = ec_eoedev_open;

   103

    eoe->dev->stop = ec_eoedev_stop;

   104

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   105

    eoe->dev->get_stats = ec_eoedev_stats;

   106

   107

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

   108

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

   109

   110

    // initialize private data

   111

    priv = netdev_priv(eoe->dev);

   112

    *priv = eoe;

   113

   114

    // Usually setting the MTU appropriately makes the upper layers

   115

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

   116

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

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    // is done "manually".

   118

#if 0

   119

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

   120

#endif

   121

   122

    // connect the net_device to the kernel

   123

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

   124

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

   125

        goto out_free;

   126

    }

   127

   128

    // make the last address octet unique

   129

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

   130

   131

    return 0;

   132

   133

 out_free:

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    free_netdev(eoe->dev);

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    eoe->dev = NULL;

   136

 out_return:

   137

    return -1;

   138

}

   139

   140

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

   141

   142

/**

   143

   EoE destructor.

   144

   Unregisteres the net_device and frees allocated memory.

   145

*/

   146

   147

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

   148

{

   149

    if (eoe->dev) {

   150

        unregister_netdev(eoe->dev);

   151

        free_netdev(eoe->dev);

   152

    }

   153

   154

    // empty transmit queue

   155

    ec_eoe_flush(eoe);

   156

   157

    if (eoe->tx_frame) {

   158

        dev_kfree_skb(eoe->tx_frame->skb);

   159

        kfree(eoe->tx_frame);

   160

    }

   161

   162

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

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}

   166

   167

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

   168

   169

/**

   170

   Empties the transmit queue.

   171

*/

   172

   173

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

   174

{

   175

    ec_eoe_frame_t *frame, *next;

   176

   177

    spin_lock_bh(&eoe->tx_queue_lock);

   178

   179

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

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        list_del(&frame->queue);

   181

        dev_kfree_skb(frame->skb);

   182

        kfree(frame);

   183

    }

   184

    eoe->tx_queued_frames = 0;

   185

   186

    spin_unlock_bh(&eoe->tx_queue_lock);

   187

}

   188

   189

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

   190

   191

/**

   192

   Sends a frame or the next fragment.

   193

*/

   194

   195

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

   196

{

   197

    size_t remaining_size, current_size, complete_offset;

   198

    unsigned int last_fragment;

   199

    uint8_t *data;

   200

#if EOE_DEBUG_LEVEL > 1

   201

    unsigned int i;

   202

#endif

   203

   204

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

   205

   206

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

   207

        current_size = remaining_size;

   208

        last_fragment = 1;

   209

    }

   210

    else {

   211

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

   212

        last_fragment = 0;

   213

    }

   214

   215

    if (eoe->tx_fragment_number) {

   216

        complete_offset = eoe->tx_offset / 32;

   217

    }

   218

    else {

   219

        complete_offset = remaining_size / 32 + 1;

   220

    }

   221

   222

#if EOE_DEBUG_LEVEL > 0

   223

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

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

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           eoe->tx_fragment_number, current_size, complete_offset,

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           eoe->tx_queued_frames);

   227

#endif

   228

   229

#if EOE_DEBUG_LEVEL > 1

   230

    EC_DBG("");

   231

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

   232

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

   233

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

   234

            printk("\n");

   235

            EC_DBG("");

   236

        }

   237

    }

   238

    printk("\n");

   239

#endif

   240

   243

        return -1;

   244

   245

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

   246

    EC_WRITE_U8 (data + 1, last_fragment);

   247

    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));

   250

   251

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

   253

   254

    eoe->tx_offset += current_size;

   255

    eoe->tx_fragment_number++;

   256

    return 0;

   257

}

   258

   259

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

   260

   261

/**

   262

   Runs the EoE state machine.

   263

*/

   264

   265

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

   266

{

   267

    if (!eoe->opened) return;

   268

   269

    // call state function

   270

    eoe->state(eoe);

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}

   272

   273

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

   274

   275

/**

   276

   Returns the state of the device.

   277

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

   278

*/

   279

   280

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

   281

{

   282

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

   283

}

   284

   285

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

   286

   287

/**

   288

   Prints EoE handler information.

   289

*/

   290

   291

void ec_eoe_print(const ec_eoe_t *eoe /**< EoE handler */)

   292

{

   293

    EC_INFO("  EoE handler %s\n", eoe->dev->name);

   294

    EC_INFO("    State: %s\n", eoe->opened ? "opened" : "closed");

   295

    if (eoe->slave)

   296

        EC_INFO("    Coupled to slave %i.\n", eoe->slave->ring_position);

   297

    else

   298

        EC_INFO("    Not coupled.\n");

   299

}

   300

   301

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

   302

 *  STATE PROCESSING FUNCTIONS

   303

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

   304

   305

/**

   306

   State: RX_START.

   307

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

   308

   slave's mailbox for a new EoE command.

   309

*/

   310

   311

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

   312

{

   313

    if (!eoe->slave->online || !eoe->slave->master->device->link_state)

   314

        return;

   315

   318

    eoe->state = ec_eoe_state_rx_check;

   319

}

   320

   321

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

   322

   323

/**

   324

   State: RX_CHECK.

   325

   Processes the checking command sent in RX_START and issues a receive

   326

   command, if new data is available.

   327

*/

   328

   329

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

   330

{

   332

        eoe->stats.rx_errors++;

   333

        eoe->state = ec_eoe_state_tx_start;

   334

        return;

   335

    }

   336

   338

        eoe->state = ec_eoe_state_tx_start;

   339

        return;

   340

    }

   341

   344

    eoe->state = ec_eoe_state_rx_fetch;

   345

}

   346

   347

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

   348

   349

/**

   350

   State: RX_FETCH.

   351

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

   352

   EoE command.

   353

*/

   354

   355

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

   356

{

   357

    size_t rec_size, data_size;

   358

    uint8_t *data, frame_type, last_fragment, time_appended;

   359

    uint8_t frame_number, fragment_offset, fragment_number;

   360

    off_t offset;

   361

   363

        eoe->stats.rx_errors++;

   364

        eoe->state = ec_eoe_state_tx_start;

   365

        return;

   366

    }

   367

   370

        eoe->stats.rx_errors++;

   371

        eoe->state = ec_eoe_state_tx_start;

   372

        return;

   373

    }

   374

   375

    frame_type = EC_READ_U16(data) & 0x000F;

   376

   377

    if (frame_type == 0x00) { // EoE Fragment Request

   378

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

   379

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

   380

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

   381

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

   382

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

   383

   384

#if EOE_DEBUG_LEVEL > 0

   385

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

   386

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

   387

               frame_number,

   388

               last_fragment ? ", last fragment" : "",

   389

               time_appended ? ", + timestamp" : "",

   390

               time_appended ? rec_size - 8 : rec_size - 4);

   391

#endif

   392

   393

#if EOE_DEBUG_LEVEL > 1

   394

        EC_DBG("");

   395

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

   396

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

   397

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

   398

                printk("\n");

   399

                EC_DBG("");

   400

            }

   401

        }

   402

        printk("\n");

   403

#endif

   404

   405

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

   406

   407

        if (!fragment_number) {

   408

            if (eoe->rx_skb) {

   409

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

   410

                dev_kfree_skb(eoe->rx_skb);

   411

            }

   412

   413

            // new socket buffer

   414

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

   415

                if (printk_ratelimit())

   416

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

   417

                eoe->stats.rx_dropped++;

   418

                eoe->state = ec_eoe_state_tx_start;

   419

                return;

   420

            }

   421

   422

            eoe->rx_skb_offset = 0;

   423

            eoe->rx_skb_size = fragment_offset * 32;

   424

            eoe->rx_expected_fragment = 0;

   425

        }

   426

        else {

   427

            if (!eoe->rx_skb) {

   428

                eoe->stats.rx_dropped++;

   429

                eoe->state = ec_eoe_state_tx_start;

   430

                return;

   431

            }

   432

   433

            offset = fragment_offset * 32;

   434

            if (offset != eoe->rx_skb_offset ||

   435

                offset + data_size > eoe->rx_skb_size ||

   436

                fragment_number != eoe->rx_expected_fragment) {

   437

                eoe->stats.rx_errors++;

   438

                eoe->state = ec_eoe_state_tx_start;

   439

                dev_kfree_skb(eoe->rx_skb);

   440

                eoe->rx_skb = NULL;

   441

                return;

   442

            }

   443

        }

   444

   445

        // copy fragment into socket buffer

   446

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

   447

        eoe->rx_skb_offset += data_size;

   448

   449

        if (last_fragment) {

   450

            // update statistics

   451

            eoe->stats.rx_packets++;

   452

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

   453

   454

#if EOE_DEBUG_LEVEL > 0

   455

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

   456

                   eoe->rx_skb->len);

   457

#endif

   458

   459

            // pass socket buffer to network stack

   460

            eoe->rx_skb->dev = eoe->dev;

   461

            eoe->rx_skb->protocol = eth_type_trans(eoe->rx_skb, eoe->dev);

   462

            eoe->rx_skb->ip_summed = CHECKSUM_UNNECESSARY;

   463

            if (netif_rx(eoe->rx_skb)) {

   464

                EC_WARN("EoE RX netif_rx failed.\n");

   465

            }

   466

            eoe->rx_skb = NULL;

   467

   468

            eoe->state = ec_eoe_state_tx_start;

   469

        }

   470

        else {

   471

            eoe->rx_expected_fragment++;

   472

#if EOE_DEBUG_LEVEL > 0

   473

            EC_DBG("EoE RX expecting fragment %i\n",

   474

                   eoe->rx_expected_fragment);

   475

#endif

   476

            eoe->state = ec_eoe_state_rx_start;

   477

        }

   478

    }

   479

    else {

   480

#if EOE_DEBUG_LEVEL > 0

   481

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

   482

#endif

   483

        eoe->stats.rx_dropped++;

   484

        eoe->state = ec_eoe_state_tx_start;

   485

    }

   486

}

   487

   488

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

   489

   490

/**

   491

   State: TX START.

   492

   Starts a new transmit sequence. If no data is available, a new receive

   493

   sequence is started instead.

   494

*/

   495