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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

    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/etherdevice.h>

    42

    43

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

    44

#include "globals.h"

    45

#include "master.h"

    46

#include "slave.h"

    47

#include "mailbox.h"

    48

#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 *);

    60

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 *);

    67

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;

    82

    eoe->state = ec_eoe_state_rx_start;

    83

    eoe->opened = 0;

    84

    eoe->rx_skb = NULL;

    85

    eoe->rx_expected_fragment = 0;

    86

    INIT_LIST_HEAD(&eoe->tx_queue);

    87

    eoe->tx_frame = NULL;

    88

    eoe->tx_queue_active = 0;

    89

    eoe->tx_queued_frames = 0;

    90

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

    91

    eoe->tx_frame_number = 0xFF;

    92

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

    93

    94

    if (!(eoe->dev =

    95

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

    96

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

    97

        goto out_return;

    98

    }

    99

   100

    // initialize net_device

   101

    eoe->dev->open = ec_eoedev_open;

   102

    eoe->dev->stop = ec_eoedev_stop;

   103

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   104

    eoe->dev->get_stats = ec_eoedev_stats;

   105

   106

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

   107

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

   108

   109

    // initialize private data

   110

    priv = netdev_priv(eoe->dev);

   111

    *priv = eoe;

   112

   113

    // Usually setting the MTU appropriately makes the upper layers

   114

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

   115

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

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    // is done "manually".

   117

#if 0

   118

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

   119

#endif

   120

   121

    // connect the net_device to the kernel

   122

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

   123

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

   124

        goto out_free;

   125

    }

   126

   127

    // make the last address octet unique

   128

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

   129

   130

    return 0;

   131

   132

 out_free:

   133

    free_netdev(eoe->dev);

   134

    eoe->dev = NULL;

   135

 out_return:

   136

    return -1;

   137

}

   138

   139

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

   140

   141

/**

   142

   EoE destructor.

   143

   Unregisteres the net_device and frees allocated memory.

   144

*/

   145

   146

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

   147

{

   148

    if (eoe->dev) {

   149

        unregister_netdev(eoe->dev);

   150

        free_netdev(eoe->dev);

   151

    }

   152

   153

    // empty transmit queue

   154

    ec_eoe_flush(eoe);

   155

   156

    if (eoe->tx_frame) {

   157

        dev_kfree_skb(eoe->tx_frame->skb);

   158

        kfree(eoe->tx_frame);

   159

    }

   160

   161

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

   162

}

   163

   164

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

   165

   166

/**

   167

   Empties the transmit queue.

   168

*/

   169

   170

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

   171

{

   172

    ec_eoe_frame_t *frame, *next;

   173

   174

    spin_lock_bh(&eoe->tx_queue_lock);

   175

   176

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

   177

        list_del(&frame->queue);

   178

        dev_kfree_skb(frame->skb);

   179

        kfree(frame);

   180

    }

   181

    eoe->tx_queued_frames = 0;

   182

   183

    spin_unlock_bh(&eoe->tx_queue_lock);

   184

}

   185

   186

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

   187

   188

/**

   189

   Sends a frame or the next fragment.

   190

*/

   191

   192

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

   193

{

   194

    size_t remaining_size, current_size, complete_offset;

   195

    unsigned int last_fragment;

   196

    uint8_t *data;

   197

#if EOE_DEBUG_LEVEL > 1

   198

    unsigned int i;

   199

#endif

   200

   201

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

   202

   203

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

   204

        current_size = remaining_size;

   205

        last_fragment = 1;

   206

    }

   207

    else {

   208

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

   209

        last_fragment = 0;

   210

    }

   211

   212

    if (eoe->tx_fragment_number) {

   213

        complete_offset = eoe->tx_offset / 32;

   214

    }

   215

    else {

   216

        complete_offset = remaining_size / 32 + 1;

   217

    }

   218

   219

#if EOE_DEBUG_LEVEL > 0

   220

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

   221

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

   222

           eoe->tx_fragment_number, current_size, complete_offset,

   223

           eoe->tx_queued_frames);

   224

#endif

   225

   226

#if EOE_DEBUG_LEVEL > 1

   227

    EC_DBG("");

   228

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

   229

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

   230

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

   231

            printk("\n");

   232

            EC_DBG("");

   233

        }

   234

    }

   235

    printk("\n");

   236

#endif

   237

   238

    if (!(data = ec_slave_mbox_prepare_send(eoe->slave, 0x02,

   239

                                            current_size + 4)))

   240

        return -1;

   241

   242

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

   243

    EC_WRITE_U8 (data + 1, last_fragment);

   244

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

   245

                            (complete_offset & 0x3F) << 6 |

   246

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

   247

   248

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

   249

    ec_master_queue_command(eoe->slave->master, &eoe->slave->mbox_command);

   250

   251

    eoe->tx_offset += current_size;

   252

    eoe->tx_fragment_number++;

   253

    return 0;

   254

}

   255

   256

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

   257

   258

/**

   259

   Runs the EoE state machine.

   260

*/

   261

   262

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

   263

{

   264

    if (!eoe->opened) return;

   265

   266

    // call state function

   267

    eoe->state(eoe);

   268

}

   269

   270

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

   271

   272

/**

   273

   Returns the state of the device.

   274

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

   275

*/

   276

   277

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

   278

{

   279

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

   280

}

   281

   282

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

   283

   284

/**

   285

   Prints EoE handler information.

   286

*/

   287

   288

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

   289

{

   290

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

   291

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

   292

    if (eoe->slave)

   293

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

   294

    else

   295

        EC_INFO("    Not coupled.\n");

   296

}

   297

   298

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

   299

 *  STATE PROCESSING FUNCTIONS

   300

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

   301

   302

/**

   303

   State: RX_START.

   304

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

   305

   slave's mailbox for a new EoE command.

   306

*/

   307

   308

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

   309

{

   310

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

   311

        return;

   312

   313

    ec_slave_mbox_prepare_check(eoe->slave);

   314

    ec_master_queue_command(eoe->slave->master, &eoe->slave->mbox_command);

   315

    eoe->state = ec_eoe_state_rx_check;

   316

}

   317

   318

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

   319

   320

/**

   321

   State: RX_CHECK.

   322

   Processes the checking command sent in RX_START and issues a receive

   323

   command, if new data is available.

   324

*/

   325

   326

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

   327

{

   328

    if (eoe->slave->mbox_command.state != EC_CMD_RECEIVED) {

   329

        eoe->stats.rx_errors++;

   330

        eoe->state = ec_eoe_state_tx_start;

   331

        return;

   332

    }

   333

   334

    if (!ec_slave_mbox_check(eoe->slave)) {

   335

        eoe->state = ec_eoe_state_tx_start;

   336

        return;

   337

    }

   338

   339

    ec_slave_mbox_prepare_fetch(eoe->slave);

   340

    ec_master_queue_command(eoe->slave->master, &eoe->slave->mbox_command);

   341

    eoe->state = ec_eoe_state_rx_fetch;

   342

}

   343

   344

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

   345

   346

/**

   347

   State: RX_FETCH.

   348

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

   349

   EoE command.

   350

*/

   351

   352

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

   353

{

   354

    size_t rec_size, data_size;

   355

    uint8_t *data, frame_type, last_fragment, time_appended;

   356

    uint8_t frame_number, fragment_offset, fragment_number;

   357

    off_t offset;

   358

   359

    if (eoe->slave->mbox_command.state != EC_CMD_RECEIVED) {

   360

        eoe->stats.rx_errors++;

   361

        eoe->state = ec_eoe_state_tx_start;

   362

        return;

   363

    }

   364

   365

    if (!(data = ec_slave_mbox_fetch(eoe->slave, 0x02, &rec_size))) {

   366

        eoe->stats.rx_errors++;

   367

        eoe->state = ec_eoe_state_tx_start;

   368

        return;

   369

    }

   370

   371

    frame_type = EC_READ_U16(data) & 0x000F;

   372

   373

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

   374

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

   375

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

   376

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

   377

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

   378

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

   379

   380

#if EOE_DEBUG_LEVEL > 0

   381

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

   382

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

   383

               frame_number,

   384

               last_fragment ? ", last fragment" : "",

   385

               time_appended ? ", + timestamp" : "",

   386

               time_appended ? rec_size - 8 : rec_size - 4);

   387

#endif

   388

   389

#if EOE_DEBUG_LEVEL > 1

   390

        EC_DBG("");

   391

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

   392

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

   393

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

   394

                printk("\n");

   395

                EC_DBG("");

   396

            }

   397

        }

   398

        printk("\n");

   399

#endif

   400

   401

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

   402

   403

        if (!fragment_number) {

   404

            if (eoe->rx_skb) {

   405

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

   406

                dev_kfree_skb(eoe->rx_skb);

   407

            }

   408

   409

            // new socket buffer

   410

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

   411

                if (printk_ratelimit())

   412

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

   413

                eoe->stats.rx_dropped++;

   414

                eoe->state = ec_eoe_state_tx_start;

   415

                return;

   416

            }

   417

   418

            eoe->rx_skb_offset = 0;

   419

            eoe->rx_skb_size = fragment_offset * 32;

   420

            eoe->rx_expected_fragment = 0;

   421

        }

   422

        else {

   423

            if (!eoe->rx_skb) {

   424

                eoe->stats.rx_dropped++;

   425

                eoe->state = ec_eoe_state_tx_start;

   426

                return;

   427

            }

   428

   429

            offset = fragment_offset * 32;

   430

            if (offset != eoe->rx_skb_offset ||

   431

                offset + data_size > eoe->rx_skb_size ||

   432

                fragment_number != eoe->rx_expected_fragment) {

   433

                eoe->stats.rx_errors++;

   434

                eoe->state = ec_eoe_state_tx_start;

   435

                dev_kfree_skb(eoe->rx_skb);

   436

                eoe->rx_skb = NULL;

   437

                return;

   438

            }

   439

        }

   440

   441

        // copy fragment into socket buffer

   442

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

   443

        eoe->rx_skb_offset += data_size;

   444

   445

        if (last_fragment) {

   446

            // update statistics

   447

            eoe->stats.rx_packets++;

   448

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

   449

   450

#if EOE_DEBUG_LEVEL > 0

   451

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

   452

                   eoe->rx_skb->len);

   453

#endif

   454

   455

            // pass socket buffer to network stack

   456

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

   457

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

   458

            eoe->rx_skb->ip_summed = CHECKSUM_UNNECESSARY;

   459

            if (netif_rx(eoe->rx_skb)) {

   460

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

   461

            }

   462

            eoe->rx_skb = NULL;

   463

   464

            eoe->state = ec_eoe_state_tx_start;

   465

        }

   466

        else {

   467

            eoe->rx_expected_fragment++;

   468

#if EOE_DEBUG_LEVEL > 0

   469

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

   470

                   eoe->rx_expected_fragment);

   471

#endif

   472

            eoe->state = ec_eoe_state_rx_start;

   473

        }

   474

    }

   475

    else {

   476

#if EOE_DEBUG_LEVEL > 0

   477

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

   478

#endif

   479

        eoe->stats.rx_dropped++;

   480

        eoe->state = ec_eoe_state_tx_start;

   481

    }

   482

}

   483

   484

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

   485

   486

/**

   487

   State: TX START.

   488

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

   489

   sequence is started instead.

   490

*/

   491

   492

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