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

     2

 *

     3

 *  $Id$

     4

 *

     5

 *  Copyright (C) 2006-2008  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 and/or

    10

 *  modify it under the terms of the GNU General Public License version 2, as

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 *  published by the Free Software Foundation.

    12

 *

    13

 *  The IgH EtherCAT Master is distributed in the hope that it will be useful,

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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General

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 *  Public License for more details.

    17

 *

    18

 *  You should have received a copy of the GNU General Public License along

    19

 *  with the IgH EtherCAT Master; if not, write to the Free Software

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 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

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 *

    22

 *  ---

    23

 *

    24

 *  The license mentioned above concerns the source code only. Using the

    25

 *  EtherCAT technology and brand is only permitted in compliance with the

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 *  industrial property and similar rights of Beckhoff Automation GmbH.

    27

 *

    28

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

    29

    30

/**

    31

   \file

    32

   Ethernet over EtherCAT (EoE).

    33

*/

    34

    35

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

    36

    37

#include <linux/version.h>

    38

#include <linux/netdevice.h>

    39

#include <linux/etherdevice.h>

    40

    41

#include "globals.h"

    42

#include "master.h"

    43

#include "slave.h"

    44

#include "mailbox.h"

    45

#include "ethernet.h"

    46

    47

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

    48

    49

/** Defines the debug level of EoE processing.

    50

 *

    51

 * 0 = No debug messages.

    52

 * 1 = Output warnings.

    53

 * 2 = Output actions.

    54

 * 3 = Output actions and frame data.

    55

 */

    56

#define EOE_DEBUG_LEVEL 1

    57

    58

/** Size of the EoE tx queue.

    59

 */

    60

#define EC_EOE_TX_QUEUE_SIZE 100

    61

    62

/** Number of tries.

    63

 */

    64

#define EC_EOE_TRIES 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 *);

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void ec_eoe_state_tx_start(ec_eoe_t *);

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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

static int ec_eoedev_set_mac(struct net_device *netdev, void *p);

    83

    84

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

    85

    86

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)

    87

/** Device operations for EoE interfaces.

    88

 */

    89

static const struct net_device_ops ec_eoedev_ops = {

    90

    .ndo_open = ec_eoedev_open,

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    .ndo_stop = ec_eoedev_stop,

    92

    .ndo_start_xmit = ec_eoedev_tx,

    93

    .ndo_get_stats = ec_eoedev_stats,

    94

    .ndo_set_mac_address = ec_eoedev_set_mac,

    95

};

    96

#endif

    97

    98

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

    99

   100

/**

   101

 * ec_eoedev_set_mac - Change the Ethernet Address of the NIC

   102

 * @netdev: network interface device structure

   103

 * @p: pointer to an address structure

   104

 *

   105

 * Returns 0 on success, negative on failure

   106

 **/

   107

static int

   108

ec_eoedev_set_mac(struct net_device *netdev, void *p)

   109

{

   110

   struct sockaddr *addr = p;

   111

   112

   if (!is_valid_ether_addr(addr->sa_data))

   113

      return -EADDRNOTAVAIL;

   114

   115

   memcpy(netdev->dev_addr, addr->sa_data, netdev->addr_len);

   116

   117

   return 0;

   118

}

   119

   120

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

   121

   122

/** EoE constructor.

   123

 *

   124

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

   125

 *

   126

 * \return Zero on success, otherwise a negative error code.

   127

 */

   128

int ec_eoe_init(

   129

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

   130

        ec_slave_t *slave /**< EtherCAT slave */

   131

        )

   132

{

   133

    ec_eoe_t **priv;

   134

    int ret = 0;

   135

    char name[EC_DATAGRAM_NAME_SIZE];

   136

   137

    struct net_device *dev;

   138

    unsigned char lo_mac[ETH_ALEN] = {0};

   139

    unsigned int use_master_mac = 0;

   140

   141

    eoe->slave = slave;

   142

   143

    ec_datagram_init(&eoe->datagram);

   144

    eoe->queue_datagram = 0;

   145

    eoe->state = ec_eoe_state_rx_start;

   146

    eoe->opened = 0;

   147

    eoe->rx_skb = NULL;

   148

    eoe->rx_expected_fragment = 0;

   149

    INIT_LIST_HEAD(&eoe->tx_queue);

   150

    eoe->tx_frame = NULL;

   151

    eoe->tx_queue_active = 0;

   152

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   153

    eoe->tx_queued_frames = 0;

   154

   155

    sema_init(&eoe->tx_queue_sem, 1);

   156

    eoe->tx_frame_number = 0xFF;

   157

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

   158

   159

    eoe->rx_counter = 0;

   160

    eoe->tx_counter = 0;

   161

    eoe->rx_rate = 0;

   162

    eoe->tx_rate = 0;

   163

    eoe->rate_jiffies = 0;

   164

    eoe->rx_idle = 1;

   165

    eoe->tx_idle = 1;

   166

   167

    /* device name eoe<MASTER>[as]<SLAVE>, because networking scripts don't

   168

     * like hyphens etc. in interface names. */

   169

    if (slave->effective_alias) {

   170

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   171

                "eoe%ua%u", slave->master->index, slave->effective_alias);

   172

    } else {

   173

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   174

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

   175

    }

   176

   177

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

   178

   179

#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 17, 0)

   180

    eoe->dev = alloc_netdev(sizeof(ec_eoe_t *), name, NET_NAME_UNKNOWN,

   181

            ether_setup);

   182

#else

   183

    eoe->dev = alloc_netdev(sizeof(ec_eoe_t *), name, ether_setup);

   184

#endif

   185

    if (!eoe->dev) {

   186

        EC_SLAVE_ERR(slave, "Unable to allocate net_device %s"

   187

                " for EoE handler!\n", name);

   188

        ret = -ENODEV;

   189

        goto out_return;

   190

    }

   191

   192

    // initialize net_device

   193

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 29)

   194

    eoe->dev->netdev_ops = &ec_eoedev_ops;

   195

#else

   196

    eoe->dev->open = ec_eoedev_open;

   197

    eoe->dev->stop = ec_eoedev_stop;

   198

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   199

    eoe->dev->get_stats = ec_eoedev_stats;

   200

#endif

   201

   202

    // First check if the MAC address assigned to the master is globally

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    // unique

   204

    if ((slave->master->devices[EC_DEVICE_MAIN].dev->dev_addr[0] & 0x02) !=

   205

            0x02) {

   206

        // The master MAC is unique and the NIC part can be used for the EoE

   207

        // interface MAC

   208

        use_master_mac = 1;

   209

    }

   210

    else {

   211

        // The master MAC is not unique, so we check for unique MAC in other

   212

        // interfaces

   213

        dev = first_net_device(&init_net);

   214

        while (dev) {

   215

            // Check if globally unique MAC address

   216

            if (dev->addr_len == ETH_ALEN) {

   217

                if (memcmp(dev->dev_addr, lo_mac, ETH_ALEN) != 0) {

   218

                    if ((dev->dev_addr[0] & 0x02) != 0x02) {

   219

                        // The first globally unique MAC address has been

   220

                        // identified

   221

                        break;

   222

                    }

   223

                }

   224

            }

   225

            dev = next_net_device(dev);

   226

        }

   227

        if (eoe->dev->addr_len == ETH_ALEN) {

   228

            if (dev) {

   229

                // A unique MAC were identified in one of the other network

   230

                // interfaces and the NIC part can be used for the EoE

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                // interface MAC.

   232

                EC_SLAVE_INFO(slave, "%s MAC address derived from"

   233

                        " NIC part of %s MAC address",

   234

                    eoe->dev->name, dev->name);

   235

                eoe->dev->dev_addr[1] = dev->dev_addr[3];

   236

                eoe->dev->dev_addr[2] = dev->dev_addr[4];

   237

                eoe->dev->dev_addr[3] = dev->dev_addr[5];

   238

            }

   239

            else {

   240

                use_master_mac = 1;

   241

            }

   242

        }

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    }

   244

    if (eoe->dev->addr_len == ETH_ALEN) {

   245

        if (use_master_mac) {

   246

            EC_SLAVE_INFO(slave, "%s MAC address derived"

   247

                    " from NIC part of %s MAC address",

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                eoe->dev->name,

   249

                slave->master->devices[EC_DEVICE_MAIN].dev->name);

   250

            eoe->dev->dev_addr[1] =

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                slave->master->devices[EC_DEVICE_MAIN].dev->dev_addr[3];

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            eoe->dev->dev_addr[2] =

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                slave->master->devices[EC_DEVICE_MAIN].dev->dev_addr[4];

   254

            eoe->dev->dev_addr[3] =

   255

                slave->master->devices[EC_DEVICE_MAIN].dev->dev_addr[5];

   256

        }

   257

        eoe->dev->dev_addr[0] = 0x02;

   258

        eoe->dev->dev_addr[4] = (uint8_t)(slave->ring_position >> 8);

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        eoe->dev->dev_addr[5] = (uint8_t)(slave->ring_position);

   260

    }

   261

   262

    // initialize private data

   263

    priv = netdev_priv(eoe->dev);

   264

    *priv = eoe;

   265

   266

    // Usually setting the MTU appropriately makes the upper layers

   267

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

   268

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

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    // is done "manually".

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#if 0

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

   272

#endif

   273

   274

    // connect the net_device to the kernel

   275

    ret = register_netdev(eoe->dev);

   276

    if (ret) {

   277

        EC_SLAVE_ERR(slave, "Unable to register net_device:"

   278

                " error %i\n", ret);

   279

        goto out_free;

   280

    }

   281

   282

    return 0;

   283

   284

 out_free:

   285

    free_netdev(eoe->dev);

   286

    eoe->dev = NULL;

   287

 out_return:

   288

    return ret;

   289

}

   290

   291

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

   292

   293

/** EoE destructor.

   294

 *

   295

 * Unregisteres the net_device and frees allocated memory.

   296

 */

   297

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

   298

{

   299

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

   300

   301

    // empty transmit queue

   302

    ec_eoe_flush(eoe);

   303

   304

    if (eoe->tx_frame) {

   305

        dev_kfree_skb(eoe->tx_frame->skb);

   306

        kfree(eoe->tx_frame);

   307

    }

   308

   309

    if (eoe->rx_skb)

   310

        dev_kfree_skb(eoe->rx_skb);

   311

   312

    free_netdev(eoe->dev);

   313

   314

    ec_datagram_clear(&eoe->datagram);

   315

}

   316

   317

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

   318

   319

/** Empties the transmit queue.

   320

 */

   321

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

   322

{

   323

    ec_eoe_frame_t *frame, *next;

   324

   325

    down(&eoe->tx_queue_sem);

   326

   327

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

   328

        list_del(&frame->queue);

   329

        dev_kfree_skb(frame->skb);

   330

        kfree(frame);

   331

    }

   332

    eoe->tx_queued_frames = 0;

   333

   334

    up(&eoe->tx_queue_sem);

   335

}

   336

   337

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

   338

   339

/** Sends a frame or the next fragment.

   340

 *

   341

 * \return Zero on success, otherwise a negative error code.

   342

 */

   343

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

   344

{

   345

    size_t remaining_size, current_size, complete_offset;

   346

    unsigned int last_fragment;

   347

    uint8_t *data;

   348

#if EOE_DEBUG_LEVEL >= 3

   349

    unsigned int i;

   350

#endif

   351

   352

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

   353

   354

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

   355

        current_size = remaining_size;

   356

        last_fragment = 1;

   357

    } else {

   358

        current_size =

   359

            ((eoe->slave->configured_tx_mailbox_size - 10) / 32) * 32;

   360

        last_fragment = 0;

   361

    }

   362

   363

    if (eoe->tx_fragment_number) {

   364

        complete_offset = eoe->tx_offset / 32;

   365

    }

   366

    else {

   367

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

   368

        complete_offset = remaining_size / 32 + 1;

   369

    }

   370

   371

#if EOE_DEBUG_LEVEL >= 2

   372

    EC_SLAVE_DBG(eoe->slave, 0, "EoE %s TX sending fragment %u%s"

   373

            " with %zu octets (%zu). %u frames queued.\n",

   374

            eoe->dev->name, eoe->tx_fragment_number,

   375

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

   376

            eoe->tx_queued_frames);

   377

#endif

   378

   379

#if EOE_DEBUG_LEVEL >= 3

   380

    EC_SLAVE_DBG(eoe->slave, 0, "");

   381

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

   382

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

   383

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

   384

            printk("\n");

   385

            EC_SLAVE_DBG(eoe->slave, 0, "");

   386

        }

   387

    }

   388

    printk("\n");

   389

#endif

   390

   391

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

   392

            EC_MBOX_TYPE_EOE, current_size + 4);

   393

    if (IS_ERR(data))

   394

        return PTR_ERR(data);

   395

   396

    EC_WRITE_U8 (data, EC_EOE_FRAMETYPE_INIT_REQ); // Initiate EoE Request

   397

    EC_WRITE_U8 (data + 1, last_fragment);

   398

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

   399

                            (complete_offset & 0x3F) << 6 |

   400

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

   401

   402

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

   403

    eoe->queue_datagram = 1;

   404

   405

    eoe->tx_offset += current_size;

   406

    eoe->tx_fragment_number++;

   407

    return 0;

   408

}

   409

   410

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

   411

   412

/** Runs the EoE state machine.

   413

 */

   414

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

   415

{

   416

    if (!eoe->opened)

   417

        return;

   418

   419

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

   420

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

   421

        return;

   422

   423

    // call state function

   424

    eoe->state(eoe);

   425

   426

    // update statistics

   427

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

   428

        eoe->rx_rate = eoe->rx_counter;

   429

        eoe->tx_rate = eoe->tx_counter;

   430

        eoe->rx_counter = 0;

   431

        eoe->tx_counter = 0;

   432

        eoe->rate_jiffies = jiffies;

   433

    }

   434

   435

    ec_datagram_output_stats(&eoe->datagram);

   436

}

   437

   438

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

   439

   440

/** Queues the datagram, if necessary.

   441

 */

   442

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

   443

{

   444

   if (eoe->queue_datagram) {

   445

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

   446

       eoe->queue_datagram = 0;

   447

   }

   448

}

   449

   450

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

   451

   452

/** Returns the state of the device.

   453

 *

   454

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

   455

 */

   456

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

   457

{

   458

    return eoe->opened;

   459

}

   460

   461

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

   462

   463

/** Returns the idle state.

   464

 *

   465

 * \retval 1 The device is idle.

   466

 * \retval 0 The device is busy.

   467

 */

   468

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

   469

{

   470

    return eoe->rx_idle && eoe->tx_idle;

   471

}

   472

   473

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

   474

 *  STATE PROCESSING FUNCTIONS

   475

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

   476

   477

/** State: RX_START.

   478

 *

   479

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

   480

 * slave's mailbox for a new EoE datagram.

   481

 *

   482

 * \todo Use both devices.

   483

 */

   484

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

   485

{

   486

    if (eoe->slave->error_flag ||