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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

   120

    /* device name eoe<MASTER>s<SLAVE>, because system tools don't like

   121

     * hyphens etc. in interface names. */

   122

    sprintf(name, "eoe%us%u", slave->master->index, slave->ring_position);

   123

   124

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

   125

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

   126

        goto out_return;

   127

    }

   128

   129

    // initialize net_device

   130

    eoe->dev->open = ec_eoedev_open;

   131

    eoe->dev->stop = ec_eoedev_stop;

   132

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   133

    eoe->dev->get_stats = ec_eoedev_stats;

   134

   135

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

   136

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

   137

   138

    // initialize private data

   139

    priv = netdev_priv(eoe->dev);

   140

    *priv = eoe;

   141

   142

    // Usually setting the MTU appropriately makes the upper layers

   143

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

   144

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

   145

    // is done "manually".

   146

#if 0

   147

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

   148

#endif

   149

   150

    // connect the net_device to the kernel

   151

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

   152

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

   153

        goto out_free;

   154

    }

   155

   156

    // make the last address octet unique

   157

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

   158

    return 0;

   159

   160

 out_free:

   161

    free_netdev(eoe->dev);

   162

    eoe->dev = NULL;

   163

 out_return:

   164

    return -1;

   165

}

   166

   167

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

   168

   169

/**

   170

   EoE destructor.

   171

   Unregisteres the net_device and frees allocated memory.

   172

*/

   173

   174

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

   175

{

   176

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

   177

    free_netdev(eoe->dev);

   178

   179

    // empty transmit queue

   180

    ec_eoe_flush(eoe);

   181

   182

    if (eoe->tx_frame) {

   183

        dev_kfree_skb(eoe->tx_frame->skb);

   184

        kfree(eoe->tx_frame);

   185

    }

   186

   187

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

   188

   189

    ec_datagram_clear(&eoe->datagram);

   190

}

   191

   192

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

   193

   194

/**

   195

   Empties the transmit queue.

   196

*/

   197

   198

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

   199

{

   200

    ec_eoe_frame_t *frame, *next;

   201

   202

    spin_lock_bh(&eoe->tx_queue_lock);

   203

   204

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

   205

        list_del(&frame->queue);

   206

        dev_kfree_skb(frame->skb);

   207

        kfree(frame);

   208

    }

   209

    eoe->tx_queued_frames = 0;

   210

   211

    spin_unlock_bh(&eoe->tx_queue_lock);

   212

}

   213

   214

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

   215

   216

/**

   217

   Sends a frame or the next fragment.

   218

*/

   219

   220

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

   221

{

   222

    size_t remaining_size, current_size, complete_offset;

   223

    unsigned int last_fragment;

   224

    uint8_t *data;

   225

#if EOE_DEBUG_LEVEL > 1

   226

    unsigned int i;

   227

#endif

   228

   229

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

   230

   231

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

   232

        current_size = remaining_size;

   233

        last_fragment = 1;

   234

    }

   235

    else {

   236

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

   237

        last_fragment = 0;

   238

    }

   239

   240

    if (eoe->tx_fragment_number) {

   241

        complete_offset = eoe->tx_offset / 32;

   242

    }

   243

    else {

   244

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

   245

        complete_offset = remaining_size / 32 + 1;

   246

    }

   247

   248

#if EOE_DEBUG_LEVEL > 0

   249

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

   250

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

   251

           eoe->tx_fragment_number, current_size, complete_offset,

   252

           eoe->tx_queued_frames);

   253

#endif

   254

   255

#if EOE_DEBUG_LEVEL > 1

   256

    EC_DBG("");

   257

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

   258

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

   259

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

   260

            printk("\n");

   261

            EC_DBG("");

   262

        }

   263

    }

   264

    printk("\n");

   265

#endif

   266

   267

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

   268

                                            0x02, current_size + 4)))

   269

        return -1;

   270

   271

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

   272

    EC_WRITE_U8 (data + 1, last_fragment);

   273

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

   274

                            (complete_offset & 0x3F) << 6 |

   275

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

   276

   277

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

   278

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

   279

   280

    eoe->tx_offset += current_size;

   281

    eoe->tx_fragment_number++;

   282

    return 0;

   283

}

   284

   285

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

   286

   287

/**

   288

   Runs the EoE state machine.

   289

*/

   290

   291

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

   292

{

   293

    if (!eoe->opened) return;

   294

   295

    // call state function

   296

    eoe->state(eoe);

   297

   298

    // update statistics

   299

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

   300

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

   301

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

   302

        eoe->rx_counter = 0;

   303

        eoe->tx_counter = 0;

   304

        eoe->rate_jiffies = jiffies;

   305

    }

   306

}

   307

   308

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

   309

   310

/**

   311

   Returns the state of the device.

   312

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

   313

*/

   314

   315

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

   316

{

   317

    return eoe->opened;

   318

}

   319

   320

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

   321

 *  STATE PROCESSING FUNCTIONS

   322

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

   323

   324

/**

   325

   State: RX_START.

   326

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

   327

   slave's mailbox for a new EoE datagram.

   328

*/

   329

   330

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

   331

{

   332

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

   333

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

   334

        return;

   335

   336

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

   337

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

   338

    eoe->state = ec_eoe_state_rx_check;

   339

}

   340

   341

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

   342

   343

/**

   344

   State: RX_CHECK.

   345

   Processes the checking datagram sent in RX_START and issues a receive

   346

   datagram, if new data is available.

   347

*/

   348

   349

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

   350

{

   351

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

   352

        eoe->stats.rx_errors++;

   353

        eoe->state = ec_eoe_state_tx_start;

   354

        return;

   355

    }

   356

   357

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

   358

        eoe->state = ec_eoe_state_tx_start;

   359

        return;

   360

    }

   361

   362

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

   363

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

   364

    eoe->state = ec_eoe_state_rx_fetch;

   365

}

   366

   367

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

   368

   369

/**

   370

   State: RX_FETCH.

   371

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

   372

   EoE datagram.

   373

*/

   374

   375

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

   376

{

   377

    size_t rec_size, data_size;

   378

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

   379

    uint8_t frame_number, fragment_offset, fragment_number;

   380

    off_t offset;

   381

#if EOE_DEBUG_LEVEL > 1

   382

    unsigned int i;

   383

#endif

   384

   385

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

   386

        eoe->stats.rx_errors++;

   387

        eoe->state = ec_eoe_state_tx_start;

   388

        return;

   389

    }

   390

   391

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

   392

                                     &mbox_prot, &rec_size))) {

   393

        eoe->stats.rx_errors++;

   394

        eoe->state = ec_eoe_state_tx_start;

   395

        return;

   396

    }

   397

   398

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

   399

        eoe->stats.rx_errors++;

   400

        eoe->state = ec_eoe_state_tx_start;

   401

        return;

   402

    }

   403

   404

    frame_type = EC_READ_U16(data) & 0x000F;

   405

   406

    if (frame_type != 0x00) {

   407

#if EOE_DEBUG_LEVEL > 0

   408

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

   409

#endif

   410

        eoe->stats.rx_dropped++;

   411

        eoe->state = ec_eoe_state_tx_start;

   412

        return;

   413

    }

   414

   415

    // EoE Fragment Request received

   416

   417

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

   418

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

   419

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

   420

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

   421

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

   422

   423

#if EOE_DEBUG_LEVEL > 0

   424

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

   425

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

   426

           frame_number,

   427

           last_fragment ? ", last fragment" : "",

   428

           time_appended ? ", + timestamp" : "",

   429

           time_appended ? rec_size - 8 : rec_size - 4);

   430

#endif

   431

   432

#if EOE_DEBUG_LEVEL > 1

   433

    EC_DBG("");

   434

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

   435

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

   436

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

   437

            printk("\n");

   438

            EC_DBG("");

   439

        }

   440

    }

   441

    printk("\n");

   442

#endif

   443

   444

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

   445

   446

    if (!fragment_number) {

   447

        if (eoe->rx_skb) {

   448

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

   449

            dev_kfree_skb(eoe->rx_skb);

   450

        }

   451

   452

        // new socket buffer

   453

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

   454

            if (printk_ratelimit())

   455

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

   456

            eoe->stats.rx_dropped++;

   457

            eoe->state = ec_eoe_state_tx_start;

   458

            return;

   459

        }

   460

   461

        eoe->rx_skb_offset = 0;

   462

        eoe->rx_skb_size = fragment_offset * 32;

   463

        eoe->rx_expected_fragment = 0;

   464

    }

   465

    else {

   466

        if (!eoe->rx_skb) {

   467

            eoe->stats.rx_dropped++;

   468

            eoe->state = ec_eoe_state_tx_start;

   469

            return;

   470

        }

   471

   472

        offset = fragment_offset * 32;

   473

        if (offset != eoe->rx_skb_offset ||

   474

            offset + data_size > eoe->rx_skb_size ||

   475

            fragment_number != eoe->rx_expected_fragment) {

   476

            dev_kfree_skb(eoe->rx_skb);

   477

            eoe->rx_skb = NULL;

   478

            eoe->stats.rx_errors++;

   479

            eoe->state = ec_eoe_state_tx_start;

   480

            return;

   481

        }

   482

    }

   483

   484

    // copy fragment into socket buffer

   485

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

   486

    eoe->rx_skb_offset += data_size;

   487

   488

    if (last_fragment) {

   489

        // update statistics