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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/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 object, creates a net_device and registeres it.

    74

*/

    75

    76

int ec_eoe_init(ec_eoe_t *eoe, /**< EoE object */

    77

                ec_slave_t *slave /**< assigned slave */

    78

                )

    79

{

    80

    ec_eoe_t **priv;

    81

    int result, i;

    82

    83

    eoe->slave = slave;

    84

    eoe->state = ec_eoe_state_rx_start;

    85

    eoe->opened = 0;

    86

    eoe->rx_skb = NULL;

    87

    eoe->rx_expected_fragment = 0;

    88

    INIT_LIST_HEAD(&eoe->tx_queue);

    89

    eoe->tx_frame = NULL;

    90

    eoe->tx_queue_active = 0;

    91

    eoe->tx_queued_frames = 0;

    92

    eoe->tx_queue_lock = SPIN_LOCK_UNLOCKED;

    93

    eoe->tx_frame_number = 0xFF;

    94

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

    95

    96

    if (!(eoe->dev =

    97

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

    98

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

    99

        goto out_return;

   100

    }

   101

   102

    // initialize net_device

   103

    eoe->dev->open = ec_eoedev_open;

   104

    eoe->dev->stop = ec_eoedev_stop;

   105

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   106

    eoe->dev->get_stats = ec_eoedev_stats;

   107

   108

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

   109

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

   110

   111

    // initialize private data

   112

    priv = netdev_priv(eoe->dev);

   113

    *priv = eoe;

   114

   115

    // Usually setting the MTU appropriately makes the upper layers

   116

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

   117

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

   118

    // is done "manually".

   119

#if 0

   120

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

   121

#endif

   122

   123

    // connect the net_device to the kernel

   124

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

   125

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

   126

        goto out_free;

   127

    }

   128

   129

    // make the last address octet unique

   130

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

   131

   132

    return 0;

   133

   134

 out_free:

   135

    free_netdev(eoe->dev);

   136

    eoe->dev = NULL;

   137

 out_return:

   138

    return -1;

   139

}

   140

   141

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

   142

   143

/**

   144

   EoE destructor.

   145

   Unregisteres the net_device and frees allocated memory.

   146

*/

   147

   148

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

   149

{

   150

    if (eoe->dev) {

   151

        unregister_netdev(eoe->dev);

   152

        free_netdev(eoe->dev);

   153

    }

   154

   155

    // empty transmit queue

   156

    ec_eoe_flush(eoe);

   157

   158

    if (eoe->tx_frame) {

   159

        dev_kfree_skb(eoe->tx_frame->skb);

   160

        kfree(eoe->tx_frame);

   161

    }

   162

   163

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

   164

}

   165

   166

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

   167

   168

/**

   169

   Empties the transmit queue.

   170

*/

   171

   172

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

   173

{

   174

    ec_eoe_frame_t *frame, *next;

   175

   176

    spin_lock_bh(&eoe->tx_queue_lock);

   177

   178

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

   179

        list_del(&frame->queue);

   180

        dev_kfree_skb(frame->skb);

   181

        kfree(frame);

   182

    }

   183

    eoe->tx_queued_frames = 0;

   184

   185

    spin_unlock_bh(&eoe->tx_queue_lock);

   186

}

   187

   188

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

   189

   190

/**

   191

   Sends a frame or the next fragment.

   192

*/

   193

   194

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

   195

{

   196

    size_t remaining_size, current_size, complete_offset;

   197

    unsigned int last_fragment;

   198

    uint8_t *data;

   199

#if EOE_DEBUG_LEVEL > 1

   200

    unsigned int i;

   201

#endif

   202

   203

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

   204

   205

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

   206

        current_size = remaining_size;

   207

        last_fragment = 1;

   208

    }

   209

    else {

   210

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

   211

        last_fragment = 0;

   212

    }

   213

   214

    if (eoe->tx_fragment_number) {

   215

        complete_offset = eoe->tx_offset / 32;

   216

    }

   217

    else {

   218

        complete_offset = remaining_size / 32 + 1;

   219

    }

   220

   221

#if EOE_DEBUG_LEVEL > 0

   222

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

   223

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

   224

           eoe->tx_fragment_number, current_size, complete_offset,

   225

           eoe->tx_queued_frames);

   226

#endif

   227

   228

#if EOE_DEBUG_LEVEL > 1

   229

    EC_DBG("");

   230

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

   231

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

   232

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

   233

            printk("\n");

   234

            EC_DBG("");

   235

        }

   236

    }

   237

    printk("\n");

   238

#endif

   239

   240

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

   241

                                            current_size + 4)))

   242

        return -1;

   243

   244

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

   245

    EC_WRITE_U8 (data + 1, last_fragment);

   246

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

   247

                            (complete_offset & 0x3F) << 6 |

   248

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

   249

   250

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

   251

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

   252

   253

    eoe->tx_offset += current_size;

   254

    eoe->tx_fragment_number++;

   255

   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 object */)

   266

{

   267

    if (!eoe->opened) return;

   268

   269

    // call state function

   270

    eoe->state(eoe);

   271

}

   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 object */)

   281

{

   282

    return eoe->opened;

   283

}

   284

   285

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

   286

   287

/**

   288

   Prints EoE object information.

   289

*/

   290

   291

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

   292

{

   293

    EC_INFO("  EoE slave %i\n", eoe->slave->ring_position);

   294

    EC_INFO("    Assigned device: %s (%s)\n", eoe->dev->name,

   295

            eoe->opened ? "opened" : "closed");

   296

}

   297

   298

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

   299

 *  STATE PROCESSING FUNCTIONS

   300

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

   301

   302

/**

   303

   State: RX_START.

   304

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

   305

   slave's mailbox for a new command.

   306

*/

   307

   308

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

   309

{

   310

    ec_slave_mbox_prepare_check(eoe->slave);

   311

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

   312

    eoe->state = ec_eoe_state_rx_check;

   313

}

   314

   315

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

   316

   317

/**

   318

   State: RX_CHECK.

   319

   Processes the checking command sent in RX_START and issues a receive

   320

   command, if new data is available.

   321

*/

   322

   323

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

   324

{

   325

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

   326

        eoe->stats.rx_errors++;

   327

        eoe->state = ec_eoe_state_tx_start;

   328

        return;

   329

    }

   330

   331

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

   332

        eoe->state = ec_eoe_state_tx_start;

   333

        return;

   334

    }

   335

   336

    ec_slave_mbox_prepare_fetch(eoe->slave);

   337

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

   338

    eoe->state = ec_eoe_state_rx_fetch;

   339

}

   340

   341

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

   342

   343

/**

   344

   State: RX_FETCH.

   345

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

   346

   EoE command.

   347

*/

   348

   349

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

   350

{

   351

    size_t rec_size, data_size;

   352

    uint8_t *data, frame_type, last_fragment, time_appended;

   353

    uint8_t frame_number, fragment_offset, fragment_number;

   354

    off_t offset;

   355

   356

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

   357

        eoe->stats.rx_errors++;

   358

        eoe->state = ec_eoe_state_tx_start;

   359

        return;

   360

    }

   361

   362

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

   363

        eoe->stats.rx_errors++;

   364

        eoe->state = ec_eoe_state_tx_start;

   365

        return;

   366

    }

   367

   368

    frame_type = EC_READ_U16(data) & 0x000F;

   369

   370

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

   371

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

   372

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

   373

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

   374

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

   375

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

   376

   377

#if EOE_DEBUG_LEVEL > 0

   378

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

   379

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

   380

               frame_number,

   381

               last_fragment ? ", last fragment" : "",

   382

               time_appended ? ", + timestamp" : "",

   383

               time_appended ? rec_size - 8 : rec_size - 4);

   384

#endif

   385

   386

#if EOE_DEBUG_LEVEL > 1

   387

        EC_DBG("");

   388

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

   389

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

   390

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

   391

                printk("\n");

   392

                EC_DBG("");

   393

            }

   394

        }

   395

        printk("\n");

   396

#endif

   397

   398

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

   399

   400

        if (!fragment_number) {

   401

            if (eoe->rx_skb) {

   402

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

   403

                dev_kfree_skb(eoe->rx_skb);

   404

            }

   405

   406

            // new socket buffer

   407

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

   408

                if (printk_ratelimit())

   409

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

   410

                eoe->stats.rx_dropped++;

   411

                eoe->state = ec_eoe_state_tx_start;

   412

                return;

   413

            }

   414

   415

            eoe->rx_skb_offset = 0;

   416

            eoe->rx_skb_size = fragment_offset * 32;

   417

            eoe->rx_expected_fragment = 0;

   418

        }

   419

        else {

   420

            if (!eoe->rx_skb) {

   421

                eoe->stats.rx_dropped++;

   422

                eoe->state = ec_eoe_state_tx_start;

   423

                return;

   424

            }

   425

   426

            offset = fragment_offset * 32;

   427

            if (offset != eoe->rx_skb_offset ||

   428

                offset + data_size > eoe->rx_skb_size ||

   429

                fragment_number != eoe->rx_expected_fragment) {

   430

                eoe->stats.rx_errors++;

   431

                eoe->state = ec_eoe_state_tx_start;

   432

                dev_kfree_skb(eoe->rx_skb);

   433

                eoe->rx_skb = NULL;

   434

                return;

   435

            }

   436

        }

   437

   438

        // copy fragment into socket buffer

   439

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

   440

        eoe->rx_skb_offset += data_size;

   441

   442

        if (last_fragment) {

   443

            // update statistics

   444

            eoe->stats.rx_packets++;

   445

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

   446

   447

#if EOE_DEBUG_LEVEL > 0

   448

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

   449

                   eoe->rx_skb->len);

   450

#endif

   451

   452

            // pass socket buffer to network stack

   453

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

   454

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

   455

            eoe->rx_skb->ip_summed = CHECKSUM_UNNECESSARY;

   456

            if (netif_rx(eoe->rx_skb)) {

   457

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

   458

            }

   459

            eoe->rx_skb = NULL;

   460

   461

            eoe->state = ec_eoe_state_tx_start;

   462

        }

   463

        else {

   464

            eoe->rx_expected_fragment++;

   465

#if EOE_DEBUG_LEVEL > 0

   466

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

   467

                   eoe->rx_expected_fragment);

   468

#endif

   469

            eoe->state = ec_eoe_state_rx_start;

   470

        }

   471

    }

   472

    else {

   473

#if EOE_DEBUG_LEVEL > 0

   474

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

   475

#endif

   476

        eoe->stats.rx_dropped++;

   477

        eoe->state = ec_eoe_state_tx_start;

   478

    }

   479

}

   480

   481

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

   482

   483

/**

   484

   State: TX START.

   485

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

   486

   sequence is started instead.

   487

*/

   488

   489

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

   490

{

   491

#if EOE_DEBUG_LEVEL > 0

   492

    unsigned int wakeup;

   493

#endif