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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

    15

 *  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

    20

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

    21

 *

    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 *);

    74

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,

    91

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

   180

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

   181

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

   182

        ret = -ENODEV;

   183

        goto out_return;

   184

    }

   185

   186

    // initialize net_device

   187

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

   188

    eoe->dev->netdev_ops = &ec_eoedev_ops;

   189

#else

   190

    eoe->dev->open = ec_eoedev_open;

   191

    eoe->dev->stop = ec_eoedev_stop;

   192

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   193

    eoe->dev->get_stats = ec_eoedev_stats;

   194

#endif

   195

   196

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

   197

    // unique

   198

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

   199

            0x02) {

   200

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

   201

        // interface MAC

   202

        use_master_mac = 1;

   203

    }

   204

    else {

   205

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

   206

        // interfaces

   207

        dev = first_net_device(&init_net);

   208

        while (dev) {

   209

            // Check if globally unique MAC address

   210

            if (dev->addr_len == ETH_ALEN) {

   211

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

   212

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

   213

                        // The first globally unique MAC address has been

   214

                        // identified

   215

                        break;

   216

                    }

   217

                }

   218

            }

   219

            dev = next_net_device(dev);

   220

        }

   221

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

   222

            if (dev) {

   223

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

   224

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

   225

                // interface MAC.

   226

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

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                        " NIC part of %s MAC address",

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

   229

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

   230

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

   231

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

   232

            }

   233

            else {

   234

                use_master_mac = 1;

   235

            }

   236

        }

   237

    }

   238

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

   239

        if (use_master_mac) {

   240

            EC_SLAVE_INFO(slave, "%s MAC address derived"

   241

                    " from NIC part of %s MAC address",

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                eoe->dev->name,

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

   244

            eoe->dev->dev_addr[1] =

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

   246

            eoe->dev->dev_addr[2] =

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

   248

            eoe->dev->dev_addr[3] =

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

   250

        }

   251

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

   252

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

   253

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

   254

    }

   255

   256

    // initialize private data

   257

    priv = netdev_priv(eoe->dev);

   258

    *priv = eoe;

   259

   260

    // Usually setting the MTU appropriately makes the upper layers

   261

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

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

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    // is done "manually".

   264

#if 0

   265

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

   266

#endif

   267

   268

    // connect the net_device to the kernel

   269

    ret = register_netdev(eoe->dev);

   270

    if (ret) {

   271

        EC_SLAVE_ERR(slave, "Unable to register net_device:"

   272

                " error %i\n", ret);

   273

        goto out_free;

   274

    }

   275

   276

    return 0;

   277

   278

 out_free:

   279

    free_netdev(eoe->dev);

   280

    eoe->dev = NULL;

   281

 out_return:

   282

    return ret;

   283

}

   284

   285

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

   286

   287

/** EoE destructor.

   288

 *

   289

 * Unregisteres the net_device and frees allocated memory.

   290

 */

   291

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

   292

{

   293

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

   294

   295

    // empty transmit queue

   296

    ec_eoe_flush(eoe);

   297

   298

    if (eoe->tx_frame) {

   299

        dev_kfree_skb(eoe->tx_frame->skb);

   300

        kfree(eoe->tx_frame);

   301

    }

   302

   303

    if (eoe->rx_skb)

   304

        dev_kfree_skb(eoe->rx_skb);

   305

   306

    free_netdev(eoe->dev);

   307

   308

    ec_datagram_clear(&eoe->datagram);

   309

}

   310

   311

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

   312

   313

/** Empties the transmit queue.

   314

 */

   315

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

   316

{

   317

    ec_eoe_frame_t *frame, *next;

   318

   319

    down(&eoe->tx_queue_sem);

   320

   321

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

   322

        list_del(&frame->queue);

   323

        dev_kfree_skb(frame->skb);

   324

        kfree(frame);

   325

    }

   326

    eoe->tx_queued_frames = 0;

   327

   328

    up(&eoe->tx_queue_sem);

   329

}

   330

   331

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

   332

   333

/** Sends a frame or the next fragment.

   334

 *

   335

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

   336

 */

   337

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

   338

{

   339

    size_t remaining_size, current_size, complete_offset;

   340

    unsigned int last_fragment;

   341

    uint8_t *data;

   342

#if EOE_DEBUG_LEVEL >= 3

   343

    unsigned int i;

   344

#endif

   345

   346

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

   347

   348

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

   349

        current_size = remaining_size;

   350

        last_fragment = 1;

   351

    } else {

   352

        current_size =

   353

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

   354

        last_fragment = 0;

   355

    }

   356

   357

    if (eoe->tx_fragment_number) {

   358

        complete_offset = eoe->tx_offset / 32;

   359

    }

   360

    else {

   361

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

   362

        complete_offset = remaining_size / 32 + 1;

   363

    }

   364

   365

#if EOE_DEBUG_LEVEL >= 2

   366

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

   367

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

   368

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

   369

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

   370

            eoe->tx_queued_frames);

   371

#endif

   372

   373

#if EOE_DEBUG_LEVEL >= 3

   374

    EC_SLAVE_DBG(master, 0, "");

   375

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

   376

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

   377

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

   378

            printk("\n");

   379

            EC_SLAVE_DBG(master, 0, "");

   380

        }

   381

    }

   382

    printk("\n");

   383

#endif

   384

   385

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

   386

            EC_MBOX_TYPE_EOE, current_size + 4);

   387

    if (IS_ERR(data))

   388

        return PTR_ERR(data);

   389

   390

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

   391

    EC_WRITE_U8 (data + 1, last_fragment);

   392

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

   393

                            (complete_offset & 0x3F) << 6 |

   394

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

   395

   396

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

   397

    eoe->queue_datagram = 1;

   398

   399

    eoe->tx_offset += current_size;

   400

    eoe->tx_fragment_number++;

   401

    return 0;

   402

}

   403

   404

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

   405

   406

/** Runs the EoE state machine.

   407

 */

   408

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

   409

{

   410

    if (!eoe->opened)

   411

        return;

   412

   413

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

   414

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

   415

        return;

   416

   417

    // call state function

   418

    eoe->state(eoe);

   419

   420

    // update statistics

   421

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

   422

        eoe->rx_rate = eoe->rx_counter;

   423

        eoe->tx_rate = eoe->tx_counter;

   424

        eoe->rx_counter = 0;

   425

        eoe->tx_counter = 0;

   426

        eoe->rate_jiffies = jiffies;

   427

    }

   428

   429

    ec_datagram_output_stats(&eoe->datagram);

   430

}

   431

   432

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

   433

   434

/** Queues the datagram, if necessary.

   435

 */

   436

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

   437

{

   438

   if (eoe->queue_datagram) {

   439

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

   440

       eoe->queue_datagram = 0;

   441

   }

   442

}

   443

   444

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

   445

   446

/** Returns the state of the device.

   447

 *

   448

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

   449

 */

   450

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

   451

{

   452

    return eoe->opened;

   453

}

   454

   455

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

   456

   457

/** Returns the idle state.

   458

 *

   459

 * \retval 1 The device is idle.

   460

 * \retval 0 The device is busy.

   461

 */

   462

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

   463

{

   464

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

   465

}

   466

   467

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

   468

 *  STATE PROCESSING FUNCTIONS

   469

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

   470

   471

/** State: RX_START.

   472

 *

   473

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

   474

 * slave's mailbox for a new EoE datagram.

   475

 *

   476

 * \todo Use both devices.

   477

 */

   478

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

   479

{

   480

    if (eoe->slave->error_flag ||

   481

            !eoe->slave->master->devices[EC_DEVICE_MAIN].link_state) {

   482

        eoe->rx_idle = 1;

   483

        eoe->tx_idle = 1;

   484

        return;

   485

    }