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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 "globals.h"

    45

#include "master.h"

    46

#include "slave.h"

    47

#include "mailbox.h"

    48

#include "ethernet.h"

    49

    50

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

    51

    52

/**

    53

 * Defines the debug level of EoE processing.

    54

 *

    55

 * 0 = No debug messages.

    56

 * 1 = Output actions.

    57

 * 2 = Output actions and frame data.

    58

 */

    59

    60

#define EOE_DEBUG_LEVEL 0

    61

    62

/** size of the EoE tx queue */

    63

#define EC_EOE_TX_QUEUE_SIZE 100

    64

    65

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

    66

    67

void ec_eoe_flush(ec_eoe_t *);

    68

    69

// state functions

    70

void ec_eoe_state_rx_start(ec_eoe_t *);

    71

void ec_eoe_state_rx_check(ec_eoe_t *);

    72

void ec_eoe_state_rx_fetch(ec_eoe_t *);

    73

void ec_eoe_state_tx_start(ec_eoe_t *);

    74

void ec_eoe_state_tx_sent(ec_eoe_t *);

    75

    76

// net_device functions

    77

int ec_eoedev_open(struct net_device *);

    78

int ec_eoedev_stop(struct net_device *);

    79

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

    80

struct net_device_stats *ec_eoedev_stats(struct net_device *);

    81

    82

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

    83

    84

/**

    85

 * EoE constructor.

    86

 * Initializes the EoE handler, creates a net_device and registers it.

    87

 */

    88

    89

int ec_eoe_init(

    90

        ec_eoe_t *eoe, /**< EoE handler */

    91

        ec_slave_t *slave /**< EtherCAT slave */

    92

        )

    93

{

    94

    ec_eoe_t **priv;

    95

    int result, i;

    96

    char name[EC_DATAGRAM_NAME_SIZE];

    97

    98

    eoe->slave = slave;

    99

   100

    ec_datagram_init(&eoe->datagram);

   101

    eoe->queue_datagram = 0;

   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>[as]<SLAVE>, because networking scripts don't

   121

     * like hyphens etc. in interface names. */

   122

    if (slave->sii.alias) {

   123

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   124

                "eoe%ua%u", slave->master->index, slave->sii.alias);

   125

    } else {

   126

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   127

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

   128

    }

   129

   130

    snprintf(eoe->datagram.name, EC_DATAGRAM_NAME_SIZE, name);

   131

   132

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

   133

        EC_ERR("Unable to allocate net_device %s for EoE handler!\n", name);

   134

        goto out_return;

   135

    }

   136

   137

    // initialize net_device

   138

    eoe->dev->open = ec_eoedev_open;

   139

    eoe->dev->stop = ec_eoedev_stop;

   140

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   141

    eoe->dev->get_stats = ec_eoedev_stats;

   142

   143

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

   144

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

   145

   146

    // initialize private data

   147

    priv = netdev_priv(eoe->dev);

   148

    *priv = eoe;

   149

   150

    // Usually setting the MTU appropriately makes the upper layers

   151

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

   152

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

   153

    // is done "manually".

   154

#if 0

   155

    eoe->dev->mtu = slave->sii.rx_mailbox_size - ETH_HLEN - 10;

   156

#endif

   157

   158

    // connect the net_device to the kernel

   159

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

   160

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

   161

        goto out_free;

   162

    }

   163

   164

    // make the last address octet unique

   165

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

   166

    return 0;

   167

   168

 out_free:

   169

    free_netdev(eoe->dev);

   170

    eoe->dev = NULL;

   171

 out_return:

   172

    return -1;

   173

}

   174

   175

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

   176

   177

/**

   178

   EoE destructor.

   179

   Unregisteres the net_device and frees allocated memory.

   180

*/

   181

   182

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

   183

{

   184

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

   185

    free_netdev(eoe->dev);

   186

   187

    // empty transmit queue

   188

    ec_eoe_flush(eoe);

   189

   190

    if (eoe->tx_frame) {

   191

        dev_kfree_skb(eoe->tx_frame->skb);

   192

        kfree(eoe->tx_frame);

   193

    }

   194

   195

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

   196

   197

    ec_datagram_clear(&eoe->datagram);

   198

}

   199

   200

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

   201

   202

/**

   203

   Empties the transmit queue.

   204

*/

   205

   206

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

   207

{

   208

    ec_eoe_frame_t *frame, *next;

   209

   210

    spin_lock_bh(&eoe->tx_queue_lock);

   211

   212

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

   213

        list_del(&frame->queue);

   214

        dev_kfree_skb(frame->skb);

   215

        kfree(frame);

   216

    }

   217

    eoe->tx_queued_frames = 0;

   218

   219

    spin_unlock_bh(&eoe->tx_queue_lock);

   220

}

   221

   222

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

   223

   224

/**

   225

   Sends a frame or the next fragment.

   226

*/

   227

   228

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

   229

{

   230

    size_t remaining_size, current_size, complete_offset;

   231

    unsigned int last_fragment;

   232

    uint8_t *data;

   233

#if EOE_DEBUG_LEVEL > 1

   234

    unsigned int i;

   235

#endif

   236

   237

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

   238

   239

    if (remaining_size <= eoe->slave->sii.tx_mailbox_size - 10) {

   240

        current_size = remaining_size;

   241

        last_fragment = 1;

   242

    }

   243

    else {

   244

        current_size = ((eoe->slave->sii.tx_mailbox_size - 10) / 32) * 32;

   245

        last_fragment = 0;

   246

    }

   247

   248

    if (eoe->tx_fragment_number) {

   249

        complete_offset = eoe->tx_offset / 32;

   250

    }

   251

    else {

   252

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

   253

        complete_offset = remaining_size / 32 + 1;

   254

    }

   255

   256

#if EOE_DEBUG_LEVEL > 0

   257

    EC_INFO("EoE %s TX sending fragment %u%s with %u octets (%u)."

   258

           " %u frames queued.\n", eoe->dev->name, eoe->tx_fragment_number,

   259

           last_fragment ? "" : "+", current_size, complete_offset,

   260

           eoe->tx_queued_frames);

   261

#endif

   262

   263

#if EOE_DEBUG_LEVEL > 1

   264

    EC_INFO("");

   265

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

   266

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

   267

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

   268

            printk("\n");

   269

            EC_INFO("");

   270

        }

   271

    }

   272

    printk("\n");

   273

#endif

   274

   275

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

   276

                                            0x02, current_size + 4)))

   277

        return -1;

   278

   279

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

   280

    EC_WRITE_U8 (data + 1, last_fragment);

   281

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

   282

                            (complete_offset & 0x3F) << 6 |

   283

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

   284

   285

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

   286

    eoe->queue_datagram = 1;

   287

   288

    eoe->tx_offset += current_size;

   289

    eoe->tx_fragment_number++;

   290

    return 0;

   291

}

   292

   293

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

   294

   295

/**

   296

   Runs the EoE state machine.

   297

*/

   298

   299

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

   300

{

   301

    if (!eoe->opened) return;

   302

   303

    // if the datagram was not sent, or is not yet received, skip this cycle

   304

    if (eoe->queue_datagram || eoe->datagram.state == EC_DATAGRAM_SENT)

   305

        return;

   306

   307

    // call state function

   308

    eoe->state(eoe);

   309

   310

    // update statistics

   311

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

   312

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

   313

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

   314

        eoe->rx_counter = 0;

   315

        eoe->tx_counter = 0;

   316

        eoe->rate_jiffies = jiffies;

   317

    }

   318

   319

    ec_datagram_output_stats(&eoe->datagram);

   320

}

   321

   322

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

   323

   324

/**

   325

 * Queues the datagram, if necessary.

   326

 */

   327

   328

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

   329

{

   330

   if (eoe->queue_datagram) {

   331

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

   332

       eoe->queue_datagram = 0;

   333

   }

   334

}

   335

   336

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

   337

   338

/**

   339

   Returns the state of the device.

   340

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

   341

*/

   342

   343

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

   344

{

   345

    return eoe->opened;

   346

}

   347

   348

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

   349

 *  STATE PROCESSING FUNCTIONS

   350

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

   351

   352

/**

   353

   State: RX_START.

   354

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

   355

   slave's mailbox for a new EoE datagram.

   356

*/

   357

   358

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

   359

{

   360

    if (eoe->slave->error_flag || !eoe->slave->master->main_device.link_state)

   361

        return;

   362

   363

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

   364

    eoe->queue_datagram = 1;

   365

    eoe->state = ec_eoe_state_rx_check;

   366

}

   367

   368

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

   369

   370

/**

   371

   State: RX_CHECK.

   372

   Processes the checking datagram sent in RX_START and issues a receive

   373

   datagram, if new data is available.

   374

*/

   375

   376

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

   377

{

   378

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

   379

        eoe->stats.rx_errors++;

   380

        eoe->state = ec_eoe_state_tx_start;

   381

        return;

   382

    }

   383

   384

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

   385

        eoe->state = ec_eoe_state_tx_start;

   386

        return;

   387

    }

   388

   389

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

   390

    eoe->queue_datagram = 1;

   391

    eoe->state = ec_eoe_state_rx_fetch;

   392

}

   393

   394

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

   395

   396

/**

   397

   State: RX_FETCH.

   398

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

   399

   EoE datagram.

   400

*/

   401

   402

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

   403

{

   404

    size_t rec_size, data_size;

   405

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

   406

    uint8_t frame_number, fragment_offset, fragment_number;

   407

    off_t offset;

   408

#if EOE_DEBUG_LEVEL > 1

   409

    unsigned int i;

   410

#endif

   411

   412

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

   413

        eoe->stats.rx_errors++;

   414

        eoe->state = ec_eoe_state_tx_start;

   415

        return;

   416

    }

   417

   418

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

   419

                                     &mbox_prot, &rec_size))) {

   420

        eoe->stats.rx_errors++;

   421

        eoe->state = ec_eoe_state_tx_start;

   422

        return;

   423

    }

   424

   425

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

   426

        eoe->stats.rx_errors++;

   427

        eoe->state = ec_eoe_state_tx_start;

   428

        return;

   429

    }

   430

   431

    frame_type = EC_READ_U16(data) & 0x000F;

   432

   433

    if (frame_type != 0x00) {

   434

#if EOE_DEBUG_LEVEL > 0

   435

        EC_INFO("EoE %s: Other frame received.\n", eoe->dev->name);

   436

#endif

   437

        eoe->stats.rx_dropped++;

   438

        eoe->state = ec_eoe_state_tx_start;

   439

        return;

   440

    }

   441

   442

    // EoE Fragment Request received

   443

   444

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

   445

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

   446

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

   447

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

   448

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

   449

   450

#if EOE_DEBUG_LEVEL > 0

   451

    EC_INFO("EoE %s RX fragment %u%s, offset %u, frame %u%s,"

   452

           " %u octets\n", eoe->dev->name, fragment_number,

   453

           last_fragment ? "" : "+", fragment_offset, frame_number, 

   454

           time_appended ? ", + timestamp" : "",

   455

           time_appended ? rec_size - 8 : rec_size - 4);

   456

#endif

   457

   458

#if EOE_DEBUG_LEVEL > 1

   459

    EC_INFO("");

   460

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

   461

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

   462

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

   463

            printk("\n");

   464

            EC_INFO("");

   465

        }

   466

    }

   467

    printk("\n");

   468

#endif

   469

   470

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

   471

   472

    if (!fragment_number) {

   473

        if (eoe->rx_skb) {

   474

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

   475

            dev_kfree_skb(eoe->rx_skb);

   476

        }

   477

   478

        // new socket buffer

   479

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

   480

            if (printk_ratelimit())

   481

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

   482

            eoe->stats.rx_dropped++;

   483

            eoe->state = ec_eoe_state_tx_start;

   484

            return;

   485

        }

   486

   487

        eoe->rx_skb_offset = 0;