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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.

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 *

    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 *);

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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,

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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

   116

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

   117

   118

   return 0;

   119

}

   120

   121

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

   122

   123

/** EoE constructor.

   124

 *

   125

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

   126

 *

   127

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

   128

 */

   129

int ec_eoe_init(

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

   131

        ec_slave_t *slave /**< EtherCAT slave */

   132

        )

   133

{

   134

    ec_eoe_t **priv;

   135

    int ret = 0;

   136

    char name[EC_DATAGRAM_NAME_SIZE];

   137

   138

    struct net_device *dev;

   139

    unsigned char lo_mac[ETH_ALEN] = {0};

   140

    unsigned int use_master_mac = 0;

   141

   142

    eoe->slave = slave;

   143

   144

    ec_datagram_init(&eoe->datagram);

   145

    eoe->queue_datagram = 0;

   146

    eoe->state = ec_eoe_state_rx_start;

   147

    eoe->opened = 0;

   148

    eoe->rx_skb = NULL;

   149

    eoe->rx_expected_fragment = 0;

   150

    INIT_LIST_HEAD(&eoe->tx_queue);

   151

    eoe->tx_frame = NULL;

   152

    eoe->tx_queue_active = 0;

   153

    eoe->tx_queue_size = EC_EOE_TX_QUEUE_SIZE;

   154

    eoe->tx_queued_frames = 0;

   155

   156

    sema_init(&eoe->tx_queue_sem, 1);

   157

    eoe->tx_frame_number = 0xFF;

   158

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

   159

   160

    eoe->rx_counter = 0;

   161

    eoe->tx_counter = 0;

   162

    eoe->rx_rate = 0;

   163

    eoe->tx_rate = 0;

   164

    eoe->rate_jiffies = 0;

   165

    eoe->rx_idle = 1;

   166

    eoe->tx_idle = 1;

   167

   168

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

   169

     * like hyphens etc. in interface names. */

   170

    if (slave->effective_alias) {

   171

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   172

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

   173

    } else {

   174

        snprintf(name, EC_DATAGRAM_NAME_SIZE,

   175

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

   176

    }

   177

   178

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

   179

   180

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

   181

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

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            ether_setup);

   183

#else

   184

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

   185

#endif

   186

    if (!eoe->dev) {

   187

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

   188

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

   189

        ret = -ENODEV;

   190

        goto out_return;

   191

    }

   192

   193

    // initialize net_device

   194

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

   195

    eoe->dev->netdev_ops = &ec_eoedev_ops;

   196

#else

   197

    eoe->dev->open = ec_eoedev_open;

   198

    eoe->dev->stop = ec_eoedev_stop;

   199

    eoe->dev->hard_start_xmit = ec_eoedev_tx;

   200

    eoe->dev->get_stats = ec_eoedev_stats;

   201

#endif

   202

   203

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

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    // unique

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

   206

            0x02) {

   207

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

   208

        // interface MAC

   209

        use_master_mac = 1;

   210

    }

   211

    else {

   212

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

   213

        // interfaces

   214

        dev = first_net_device(&init_net);

   215

        while (dev) {

   216

            // Check if globally unique MAC address

   217

            if (dev->addr_len == ETH_ALEN) {

   218

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

   219

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

   220

                        // The first globally unique MAC address has been

   221

                        // identified

   222

                        break;

   223

                    }

   224

                }

   225

            }

   226

            dev = next_net_device(dev);

   227

        }

   228

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

   229

            if (dev) {

   230

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

   231

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

   232

                // interface MAC.

   233

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

   234

                        " NIC part of %s MAC address",

   235

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

   236

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

   237

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

   238

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

   239

            }

   240

            else {

   241

                use_master_mac = 1;

   242

            }

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        }

   244

    }

   245

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

   246

        if (use_master_mac) {

   247

            EC_SLAVE_INFO(slave, "%s MAC address derived"

   248

                    " from NIC part of %s MAC address",

   249

                eoe->dev->name,

   250

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

   251

            eoe->dev->dev_addr[1] =

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

   253

            eoe->dev->dev_addr[2] =

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

   255

            eoe->dev->dev_addr[3] =

   256

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

   257

        }

   258

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

   259

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

   260

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

   261

    }

   262

   263

    // initialize private data

   264

    priv = netdev_priv(eoe->dev);

   265

    *priv = eoe;

   266

   267

    // Usually setting the MTU appropriately makes the upper layers

   268

    // 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".

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#if 0

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

   273

#endif

   274

   275

    // connect the net_device to the kernel

   276

    ret = register_netdev(eoe->dev);

   277

    if (ret) {

   278

        EC_SLAVE_ERR(slave, "Unable to register net_device:"

   279

                " error %i\n", ret);

   280

        goto out_free;

   281

    }

   282

   283

    return 0;

   284

   285

 out_free:

   286

    free_netdev(eoe->dev);

   287

    eoe->dev = NULL;

   288

 out_return:

   289

    return ret;

   290

}

   291

   292

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

   293

   294

/** EoE destructor.

   295

 *

   296

 * Unregisteres the net_device and frees allocated memory.

   297

 */

   298

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

   299

{

   300

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

   301

   302

    // empty transmit queue

   303

    ec_eoe_flush(eoe);

   304

   305

    if (eoe->tx_frame) {

   306

        dev_kfree_skb(eoe->tx_frame->skb);

   307

        kfree(eoe->tx_frame);

   308

    }

   309

   310

    if (eoe->rx_skb)

   311

        dev_kfree_skb(eoe->rx_skb);

   312

   313

    free_netdev(eoe->dev);

   314

   315

    ec_datagram_clear(&eoe->datagram);

   316

}

   317

   318

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

   319

   320

/** Empties the transmit queue.

   321

 */

   322

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

   323

{

   324

    ec_eoe_frame_t *frame, *next;

   325

   326

    down(&eoe->tx_queue_sem);

   327

   328

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

   329

        list_del(&frame->queue);

   330

        dev_kfree_skb(frame->skb);

   331

        kfree(frame);

   332

    }

   333

    eoe->tx_queued_frames = 0;

   334

   335

    up(&eoe->tx_queue_sem);

   336

}

   337

   338

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

   339

   340

/** Sends a frame or the next fragment.

   341

 *

   342

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

   343

 */

   344

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

   345

{

   346

    size_t remaining_size, current_size, complete_offset;

   347

    unsigned int last_fragment;

   348

    uint8_t *data;

   349

#if EOE_DEBUG_LEVEL >= 3

   350

    unsigned int i;

   351

#endif

   352

   353

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

   354

   355

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

   356

        current_size = remaining_size;

   357

        last_fragment = 1;

   358

    } else {

   359

        current_size =

   360

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

   361

        last_fragment = 0;

   362

    }

   363

   364

    if (eoe->tx_fragment_number) {

   365

        complete_offset = eoe->tx_offset / 32;

   366

    }

   367

    else {

   368

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

   369

        complete_offset = remaining_size / 32 + 1;

   370

    }

   371

   372

#if EOE_DEBUG_LEVEL >= 2

   373

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

   374

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

   375

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

   376

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

   377

            eoe->tx_queued_frames);

   378

#endif

   379

   380

#if EOE_DEBUG_LEVEL >= 3

   381

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

   382

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

   383

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

   384

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

   385

            printk("\n");

   386

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

   387

        }

   388

    }

   389

    printk("\n");

   390

#endif

   391

   392

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

   393

            EC_MBOX_TYPE_EOE, current_size + 4);

   394

    if (IS_ERR(data)) {

   395

        return PTR_ERR(data);

   396

    }

   397

   398

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

   399

    EC_WRITE_U8 (data + 1, last_fragment);

   400

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

   401

                            (complete_offset & 0x3F) << 6 |

   402

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

   403

   404

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

   405

    eoe->queue_datagram = 1;

   406

   407

    eoe->tx_offset += current_size;

   408

    eoe->tx_fragment_number++;

   409

    return 0;

   410

}

   411

   412

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

   413

   414

/** Runs the EoE state machine.

   415

 */

   416

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

   417

{

   418

    if (!eoe->opened) {

   419

        return;

   420

    }

   421

   422

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

   423

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

   424

        return;

   425

    }

   426

   427

    // call state function

   428

    eoe->state(eoe);

   429

   430

    // update statistics

   431

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

   432

        eoe->rx_rate = eoe->rx_counter;

   433

        eoe->tx_rate = eoe->tx_counter;

   434

        eoe->rx_counter = 0;

   435

        eoe->tx_counter = 0;

   436

        eoe->rate_jiffies = jiffies;

   437

    }

   438

   439

    ec_datagram_output_stats(&eoe->datagram);

   440

}

   441

   442

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

   443

   444

/** Queues the datagram, if necessary.

   445

 */

   446

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

   447

{

   448

   if (eoe->queue_datagram) {

   449

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

   450

       eoe->queue_datagram = 0;

   451

   }

   452

}

   453

   454

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

   455

   456

/** Returns the state of the device.

   457

 *

   458

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

   459

 */

   460

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

   461

{

   462

    return eoe->opened;

   463

}

   464

   465

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

   466

   467

/** Returns the idle state.

   468

 *

   469

 * \retval 1 The device is idle.

   470

 * \retval 0 The device is busy.

   471

 */

   472

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

   473

{

   474

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

   475

}

   476

   477

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

   478

 *  STATE PROCESSING FUNCTIONS

   479

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

   480

   481

/** State: RX_START.

   482

 *

   483

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

   484

 * slave's mailbox for a new EoE datagram.

   485

 *

   486

 * \todo Use both devices.