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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 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[20];

    98

    99

    eoe->slave = slave;

   100

   101

    ec_datagram_init(&eoe->datagram);

   102

    eoe->state = ec_eoe_state_rx_start;

   103

    eoe->opened = 0;

   104

    eoe->rx_skb = NULL;

   105

    eoe->rx_expected_fragment = 0;

   106

    INIT_LIST_HEAD(&eoe->tx_queue);

   107

    eoe->tx_frame = NULL;

   108

    eoe->tx_queue_active = 0;

   109

    eoe->tx_queued_frames = 0;

   110

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

   111

    eoe->tx_frame_number = 0xFF;

   112

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

   113

   114

    eoe->rx_counter = 0;

   115

    eoe->tx_counter = 0;

   116

    eoe->rx_rate = 0;

   117

    eoe->tx_rate = 0;

   118

    eoe->rate_jiffies = 0;

   119

   121

   122

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

   123

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

   124

        goto out_return;

   125

    }

   126

   127

    // initialize net_device

   128

    eoe->dev->open = ec_eoedev_open;

   129

    eoe->dev->stop = ec_eoedev_stop;

   130

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   131

    eoe->dev->get_stats = ec_eoedev_stats;

   132

   133

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

   134

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

   135

   136

    // initialize private data

   137

    priv = netdev_priv(eoe->dev);

   138

    *priv = eoe;

   139

   140

    // Usually setting the MTU appropriately makes the upper layers

   141

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

   142

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

   143

    // is done "manually".

   144

#if 0

   145

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

   146

#endif

   147

   148

    // connect the net_device to the kernel

   149

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

   150

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

   151

        goto out_free;

   152

    }

   153

   154

    // make the last address octet unique

   155

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

   156

    return 0;

   157

   158

 out_free:

   159

    free_netdev(eoe->dev);

   160

    eoe->dev = NULL;

   161

 out_return:

   162

    return -1;

   163

}

   164

   165

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

   166

   167

/**

   168

   EoE destructor.

   169

   Unregisteres the net_device and frees allocated memory.

   170

*/

   171

   172

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

   173

{

   174

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

   175

    free_netdev(eoe->dev);

   176

   177

    // empty transmit queue

   178

    ec_eoe_flush(eoe);

   179

   180

    if (eoe->tx_frame) {

   181

        dev_kfree_skb(eoe->tx_frame->skb);

   182

        kfree(eoe->tx_frame);

   183

    }

   184

   185

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

   186

   187

    ec_datagram_clear(&eoe->datagram);

   188

}

   189

   190

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

   191

   192

/**

   193

   Empties the transmit queue.

   194

*/

   195

   196

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

   197

{

   198

    ec_eoe_frame_t *frame, *next;

   199

   200

    spin_lock_bh(&eoe->tx_queue_lock);

   201

   202

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

   203

        list_del(&frame->queue);

   204

        dev_kfree_skb(frame->skb);

   205

        kfree(frame);

   206

    }

   207

    eoe->tx_queued_frames = 0;

   208

   209

    spin_unlock_bh(&eoe->tx_queue_lock);

   210

}

   211

   212

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

   213

   214

/**

   215

   Sends a frame or the next fragment.

   216

*/

   217

   218

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

   219

{

   220

    size_t remaining_size, current_size, complete_offset;

   221

    unsigned int last_fragment;

   222

    uint8_t *data;

   223

#if EOE_DEBUG_LEVEL > 1

   224

    unsigned int i;

   225

#endif

   226

   227

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

   228

   229

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

   230

        current_size = remaining_size;

   231

        last_fragment = 1;

   232

    }

   233

    else {

   234

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

   235

        last_fragment = 0;

   236

    }

   237

   238

    if (eoe->tx_fragment_number) {

   239

        complete_offset = eoe->tx_offset / 32;

   240

    }

   241

    else {

   242

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

   243

        complete_offset = remaining_size / 32 + 1;

   244

    }

   245

   246

#if EOE_DEBUG_LEVEL > 0

   247

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

   248

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

   249

           eoe->tx_fragment_number, current_size, complete_offset,

   250

           eoe->tx_queued_frames);

   251

#endif

   252

   253

#if EOE_DEBUG_LEVEL > 1

   254

    EC_DBG("");

   255

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

   256

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

   257

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

   258

            printk("\n");

   259

            EC_DBG("");

   260

        }

   261

    }

   262

    printk("\n");

   263

#endif

   264

   265

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

   266

                                            0x02, current_size + 4)))

   267

        return -1;

   268

   269

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

   270

    EC_WRITE_U8 (data + 1, last_fragment);

   271

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

   272

                            (complete_offset & 0x3F) << 6 |

   273

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

   274

   275

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

   276

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

   277

   278

    eoe->tx_offset += current_size;

   279

    eoe->tx_fragment_number++;

   280

    return 0;

   281

}

   282

   283

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

   284

   285

/**

   286

   Runs the EoE state machine.

   287

*/

   288

   289

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

   290

{

   291

    if (!eoe->opened) return;

   292

   293

    // call state function

   294

    eoe->state(eoe);

   295

   296

    // update statistics

   297

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

   298

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

   299

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

   300

        eoe->rx_counter = 0;

   301

        eoe->tx_counter = 0;

   302

        eoe->rate_jiffies = jiffies;

   303

    }

   304

}

   305

   306

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

   307

   308

/**

   309

   Returns the state of the device.

   310

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

   311

*/

   312

   313

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

   314

{

   315

    return eoe->opened;

   316

}

   317

   318

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

   319

 *  STATE PROCESSING FUNCTIONS

   320

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

   321

   322

/**

   323

   State: RX_START.

   324

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

   325

   slave's mailbox for a new EoE datagram.

   326

*/

   327

   328

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

   329

{

   330

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

   331

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

   332

        return;

   333

   334

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

   335

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

   336

    eoe->state = ec_eoe_state_rx_check;

   337

}

   338

   339

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

   340

   341

/**

   342

   State: RX_CHECK.

   343

   Processes the checking datagram sent in RX_START and issues a receive

   344

   datagram, if new data is available.

   345

*/

   346

   347

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

   348

{

   349

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

   350

        eoe->stats.rx_errors++;

   351

        eoe->state = ec_eoe_state_tx_start;

   352

        return;

   353

    }

   354

   355

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

   356

        eoe->state = ec_eoe_state_tx_start;

   357

        return;

   358

    }

   359

   360

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

   361

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

   362

    eoe->state = ec_eoe_state_rx_fetch;

   363

}

   364

   365

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

   366

   367

/**

   368

   State: RX_FETCH.

   369

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

   370

   EoE datagram.

   371

*/

   372

   373

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

   374

{

   375

    size_t rec_size, data_size;

   376

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

   377

    uint8_t frame_number, fragment_offset, fragment_number;

   378

    off_t offset;

   379

#if EOE_DEBUG_LEVEL > 1

   380

    unsigned int i;

   381

#endif

   382

   383

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

   384

        eoe->stats.rx_errors++;

   385

        eoe->state = ec_eoe_state_tx_start;

   386

        return;

   387

    }

   388

   389

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

   390

                                     &mbox_prot, &rec_size))) {

   391

        eoe->stats.rx_errors++;

   392

        eoe->state = ec_eoe_state_tx_start;

   393

        return;

   394

    }

   395

   396

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

   397

        eoe->stats.rx_errors++;

   398

        eoe->state = ec_eoe_state_tx_start;

   399

        return;

   400

    }

   401

   402

    frame_type = EC_READ_U16(data) & 0x000F;

   403

   404

    if (frame_type != 0x00) {

   405

#if EOE_DEBUG_LEVEL > 0

   406

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

   407

#endif

   408

        eoe->stats.rx_dropped++;

   409

        eoe->state = ec_eoe_state_tx_start;

   410

        return;

   411

    }

   412

   413

    // EoE Fragment Request received

   414

   415

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

   416

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

   417

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

   418

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

   419

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

   420

   421

#if EOE_DEBUG_LEVEL > 0

   422

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

   423

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

   424

           frame_number,

   425

           last_fragment ? ", last fragment" : "",

   426

           time_appended ? ", + timestamp" : "",

   427

           time_appended ? rec_size - 8 : rec_size - 4);

   428

#endif

   429

   430

#if EOE_DEBUG_LEVEL > 1

   431

    EC_DBG("");

   432

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

   433

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

   434

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

   435

            printk("\n");

   436

            EC_DBG("");

   437

        }

   438

    }

   439

    printk("\n");

   440

#endif

   441

   442

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

   443

   444

    if (!fragment_number) {

   445

        if (eoe->rx_skb) {

   446

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

   447

            dev_kfree_skb(eoe->rx_skb);

   448

        }

   449

   450

        // new socket buffer

   451

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

   452

            if (printk_ratelimit())

   453

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

   454

            eoe->stats.rx_dropped++;

   455

            eoe->state = ec_eoe_state_tx_start;

   456

            return;

   457

        }

   458

   459

        eoe->rx_skb_offset = 0;

   460

        eoe->rx_skb_size = fragment_offset * 32;

   461

        eoe->rx_expected_fragment = 0;

   462

    }

   463

    else {

   464

        if (!eoe->rx_skb) {

   465

            eoe->stats.rx_dropped++;

   466

            eoe->state = ec_eoe_state_tx_start;

   467

            return;

   468

        }

   469

   470

        offset = fragment_offset * 32;

   471

        if (offset != eoe->rx_skb_offset ||

   472

            offset + data_size > eoe->rx_skb_size ||

   473

            fragment_number != eoe->rx_expected_fragment) {

   474

            dev_kfree_skb(eoe->rx_skb);

   475

            eoe->rx_skb = NULL;

   476

            eoe->stats.rx_errors++;

   477

            eoe->state = ec_eoe_state_tx_start;

   478

            return;

   479

        }

   480

    }

   481

   482

    // copy fragment into socket buffer

   483

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

   484

    eoe->rx_skb_offset += data_size;

   485

   486

    if (last_fragment) {

   487

        // update statistics

   488

        eoe->stats.rx_packets++;

   489

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