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

     2

     3

  Intel PRO/1000 Linux driver

     4

  Copyright(c) 1999 - 2012 Intel Corporation.

     5

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  This program is free software; you can redistribute it and/or modify it

     7

  under the terms and conditions of the GNU General Public License,

     8

  version 2, as published by the Free Software Foundation.

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    10

  This program is distributed in the hope it will be useful, but WITHOUT

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  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

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  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

    13

  more details.

    14

    15

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

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  this program; if not, write to the Free Software Foundation, Inc.,

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

    18

    19

  The full GNU General Public License is included in this distribution in

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  the file called "COPYING".

    21

    22

  Contact Information:

    23

  Linux NICS <linux.nics@intel.com>

    24

  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>

    25

  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497

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    27

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

    28

    29

/* ethtool support for e1000 */

    30

    31

#include <linux/netdevice.h>

    32

#include <linux/interrupt.h>

    33

#include <linux/ethtool.h>

    34

#include <linux/pci.h>

    35

#include <linux/slab.h>

    36

#include <linux/delay.h>

    37

#include <linux/vmalloc.h>

    38

#include <linux/pm_runtime.h>

    39

    40

#include "e1000-3.8-ethercat.h"

    41

    42

enum {NETDEV_STATS, E1000_STATS};

    43

    44

struct e1000_stats {

    45

	char stat_string[ETH_GSTRING_LEN];

    46

	int type;

    47

	int sizeof_stat;

    48

	int stat_offset;

    49

};

    50

    51

#define E1000_STAT(str, m) { \

    52

		.stat_string = str, \

    53

		.type = E1000_STATS, \

    54

		.sizeof_stat = sizeof(((struct e1000_adapter *)0)->m), \

    55

		.stat_offset = offsetof(struct e1000_adapter, m) }

    56

#define E1000_NETDEV_STAT(str, m) { \

    57

		.stat_string = str, \

    58

		.type = NETDEV_STATS, \

    59

		.sizeof_stat = sizeof(((struct rtnl_link_stats64 *)0)->m), \

    60

		.stat_offset = offsetof(struct rtnl_link_stats64, m) }

    61

    62

static const struct e1000_stats e1000_gstrings_stats[] = {

    63

	E1000_STAT("rx_packets", stats.gprc),

    64

	E1000_STAT("tx_packets", stats.gptc),

    65

	E1000_STAT("rx_bytes", stats.gorc),

    66

	E1000_STAT("tx_bytes", stats.gotc),

    67

	E1000_STAT("rx_broadcast", stats.bprc),

    68

	E1000_STAT("tx_broadcast", stats.bptc),

    69

	E1000_STAT("rx_multicast", stats.mprc),

    70

	E1000_STAT("tx_multicast", stats.mptc),

    71

	E1000_NETDEV_STAT("rx_errors", rx_errors),

    72

	E1000_NETDEV_STAT("tx_errors", tx_errors),

    73

	E1000_NETDEV_STAT("tx_dropped", tx_dropped),

    74

	E1000_STAT("multicast", stats.mprc),

    75

	E1000_STAT("collisions", stats.colc),

    76

	E1000_NETDEV_STAT("rx_length_errors", rx_length_errors),

    77

	E1000_NETDEV_STAT("rx_over_errors", rx_over_errors),

    78

	E1000_STAT("rx_crc_errors", stats.crcerrs),

    79

	E1000_NETDEV_STAT("rx_frame_errors", rx_frame_errors),

    80

	E1000_STAT("rx_no_buffer_count", stats.rnbc),

    81

	E1000_STAT("rx_missed_errors", stats.mpc),

    82

	E1000_STAT("tx_aborted_errors", stats.ecol),

    83

	E1000_STAT("tx_carrier_errors", stats.tncrs),

    84

	E1000_NETDEV_STAT("tx_fifo_errors", tx_fifo_errors),

    85

	E1000_NETDEV_STAT("tx_heartbeat_errors", tx_heartbeat_errors),

    86

	E1000_STAT("tx_window_errors", stats.latecol),

    87

	E1000_STAT("tx_abort_late_coll", stats.latecol),

    88

	E1000_STAT("tx_deferred_ok", stats.dc),

    89

	E1000_STAT("tx_single_coll_ok", stats.scc),

    90

	E1000_STAT("tx_multi_coll_ok", stats.mcc),

    91

	E1000_STAT("tx_timeout_count", tx_timeout_count),

    92

	E1000_STAT("tx_restart_queue", restart_queue),

    93

	E1000_STAT("rx_long_length_errors", stats.roc),

    94

	E1000_STAT("rx_short_length_errors", stats.ruc),

    95

	E1000_STAT("rx_align_errors", stats.algnerrc),

    96

	E1000_STAT("tx_tcp_seg_good", stats.tsctc),

    97

	E1000_STAT("tx_tcp_seg_failed", stats.tsctfc),

    98

	E1000_STAT("rx_flow_control_xon", stats.xonrxc),

    99

	E1000_STAT("rx_flow_control_xoff", stats.xoffrxc),

   100

	E1000_STAT("tx_flow_control_xon", stats.xontxc),

   101

	E1000_STAT("tx_flow_control_xoff", stats.xofftxc),

   102

	E1000_STAT("rx_long_byte_count", stats.gorc),

   103

	E1000_STAT("rx_csum_offload_good", hw_csum_good),

   104

	E1000_STAT("rx_csum_offload_errors", hw_csum_err),

   105

	E1000_STAT("rx_header_split", rx_hdr_split),

   106

	E1000_STAT("alloc_rx_buff_failed", alloc_rx_buff_failed),

   107

	E1000_STAT("tx_smbus", stats.mgptc),

   108

	E1000_STAT("rx_smbus", stats.mgprc),

   109

	E1000_STAT("dropped_smbus", stats.mgpdc),

   110

	E1000_STAT("rx_dma_failed", rx_dma_failed),

   111

	E1000_STAT("tx_dma_failed", tx_dma_failed),

   112

	E1000_STAT("uncorr_ecc_errors", uncorr_errors),

   113

	E1000_STAT("corr_ecc_errors", corr_errors),

   114

};

   115

   116

#define E1000_GLOBAL_STATS_LEN	ARRAY_SIZE(e1000_gstrings_stats)

   117

#define E1000_STATS_LEN (E1000_GLOBAL_STATS_LEN)

   118

static const char e1000_gstrings_test[][ETH_GSTRING_LEN] = {

   119

	"Register test  (offline)", "Eeprom test    (offline)",

   120

	"Interrupt test (offline)", "Loopback test  (offline)",

   121

	"Link test   (on/offline)"

   122

};

   123

#define E1000_TEST_LEN ARRAY_SIZE(e1000_gstrings_test)

   124

   125

static int e1000_get_settings(struct net_device *netdev,

   126

			      struct ethtool_cmd *ecmd)

   127

{

   128

	struct e1000_adapter *adapter = netdev_priv(netdev);

   129

	struct e1000_hw *hw = &adapter->hw;

   130

	u32 speed;

   131

   132

	if (hw->phy.media_type == e1000_media_type_copper) {

   133

   134

		ecmd->supported = (SUPPORTED_10baseT_Half |

   135

				   SUPPORTED_10baseT_Full |

   136

				   SUPPORTED_100baseT_Half |

   137

				   SUPPORTED_100baseT_Full |

   138

				   SUPPORTED_1000baseT_Full |

   139

				   SUPPORTED_Autoneg |

   140

				   SUPPORTED_TP);

   141

		if (hw->phy.type == e1000_phy_ife)

   142

			ecmd->supported &= ~SUPPORTED_1000baseT_Full;

   143

		ecmd->advertising = ADVERTISED_TP;

   144

   145

		if (hw->mac.autoneg == 1) {

   146

			ecmd->advertising |= ADVERTISED_Autoneg;

   147

			/* the e1000 autoneg seems to match ethtool nicely */

   148

			ecmd->advertising |= hw->phy.autoneg_advertised;

   149

		}

   150

   151

		ecmd->port = PORT_TP;

   152

		ecmd->phy_address = hw->phy.addr;

   153

		ecmd->transceiver = XCVR_INTERNAL;

   154

   155

	} else {

   156

		ecmd->supported   = (SUPPORTED_1000baseT_Full |

   157

				     SUPPORTED_FIBRE |

   158

				     SUPPORTED_Autoneg);

   159

   160

		ecmd->advertising = (ADVERTISED_1000baseT_Full |

   161

				     ADVERTISED_FIBRE |

   162

				     ADVERTISED_Autoneg);

   163

   164

		ecmd->port = PORT_FIBRE;

   165

		ecmd->transceiver = XCVR_EXTERNAL;

   166

	}

   167

   168

	speed = -1;

   169

	ecmd->duplex = -1;

   170

   171

	if (netif_running(netdev)) {

   172

		if (netif_carrier_ok(netdev)) {

   173

			speed = adapter->link_speed;

   174

			ecmd->duplex = adapter->link_duplex - 1;

   175

		}

   176

	} else {

   177

		u32 status = er32(STATUS);

   178

		if (status & E1000_STATUS_LU) {

   179

			if (status & E1000_STATUS_SPEED_1000)

   180

				speed = SPEED_1000;

   181

			else if (status & E1000_STATUS_SPEED_100)

   182

				speed = SPEED_100;

   183

			else

   184

				speed = SPEED_10;

   185

   186

			if (status & E1000_STATUS_FD)

   187

				ecmd->duplex = DUPLEX_FULL;

   188

			else

   189

				ecmd->duplex = DUPLEX_HALF;

   190

		}

   191

	}

   192

   193

	ethtool_cmd_speed_set(ecmd, speed);

   194

	ecmd->autoneg = ((hw->phy.media_type == e1000_media_type_fiber) ||

   195

			 hw->mac.autoneg) ? AUTONEG_ENABLE : AUTONEG_DISABLE;

   196

   197

	/* MDI-X => 2; MDI =>1; Invalid =>0 */

   198

	if ((hw->phy.media_type == e1000_media_type_copper) &&

   199

	    netif_carrier_ok(netdev))

   200

		ecmd->eth_tp_mdix = hw->phy.is_mdix ? ETH_TP_MDI_X :

   201

		                                      ETH_TP_MDI;

   202

	else

   203

		ecmd->eth_tp_mdix = ETH_TP_MDI_INVALID;

   204

   205

	if (hw->phy.mdix == AUTO_ALL_MODES)

   206

		ecmd->eth_tp_mdix_ctrl = ETH_TP_MDI_AUTO;

   207

	else

   208

		ecmd->eth_tp_mdix_ctrl = hw->phy.mdix;

   209

   210

	return 0;

   211

}

   212

   213

static int e1000_set_spd_dplx(struct e1000_adapter *adapter, u32 spd, u8 dplx)

   214

{

   215

	struct e1000_mac_info *mac = &adapter->hw.mac;

   216

   217

	mac->autoneg = 0;

   218

   219

	/* Make sure dplx is at most 1 bit and lsb of speed is not set

   220

	 * for the switch() below to work

   221

	 */

   222

	if ((spd & 1) || (dplx & ~1))

   223

		goto err_inval;

   224

   225

	/* Fiber NICs only allow 1000 gbps Full duplex */

   226

	if ((adapter->hw.phy.media_type == e1000_media_type_fiber) &&

   227

	    spd != SPEED_1000 &&

   228

	    dplx != DUPLEX_FULL) {

   229

		goto err_inval;

   230

	}

   231

   232

	switch (spd + dplx) {

   233

	case SPEED_10 + DUPLEX_HALF:

   234

		mac->forced_speed_duplex = ADVERTISE_10_HALF;

   235

		break;

   236

	case SPEED_10 + DUPLEX_FULL:

   237

		mac->forced_speed_duplex = ADVERTISE_10_FULL;

   238

		break;

   239

	case SPEED_100 + DUPLEX_HALF:

   240

		mac->forced_speed_duplex = ADVERTISE_100_HALF;

   241

		break;

   242

	case SPEED_100 + DUPLEX_FULL:

   243

		mac->forced_speed_duplex = ADVERTISE_100_FULL;

   244

		break;

   245

	case SPEED_1000 + DUPLEX_FULL:

   246

		mac->autoneg = 1;

   247

		adapter->hw.phy.autoneg_advertised = ADVERTISE_1000_FULL;

   248

		break;

   249

	case SPEED_1000 + DUPLEX_HALF: /* not supported */

   250

	default:

   251

		goto err_inval;

   252

	}

   253

   254

	/* clear MDI, MDI(-X) override is only allowed when autoneg enabled */

   255

	adapter->hw.phy.mdix = AUTO_ALL_MODES;

   256

   257

	return 0;

   258

   259

err_inval:

   260

	e_err("Unsupported Speed/Duplex configuration\n");

   261

	return -EINVAL;

   262

}

   263

   264

static int e1000_set_settings(struct net_device *netdev,

   265

			      struct ethtool_cmd *ecmd)

   266

{

   267

	struct e1000_adapter *adapter = netdev_priv(netdev);

   268

	struct e1000_hw *hw = &adapter->hw;

   269

   270

	/* When SoL/IDER sessions are active, autoneg/speed/duplex

   271

	 * cannot be changed

   272

	 */

   273

	if (hw->phy.ops.check_reset_block &&

   274

	    hw->phy.ops.check_reset_block(hw)) {

   275

		e_err("Cannot change link characteristics when SoL/IDER is active.\n");

   276

		return -EINVAL;

   277

	}

   278

   279

	/* MDI setting is only allowed when autoneg enabled because

   280

	 * some hardware doesn't allow MDI setting when speed or

   281

	 * duplex is forced.

   282

	 */

   283

	if (ecmd->eth_tp_mdix_ctrl) {

   284

		if (hw->phy.media_type != e1000_media_type_copper)

   285

			return -EOPNOTSUPP;

   286

   287

		if ((ecmd->eth_tp_mdix_ctrl != ETH_TP_MDI_AUTO) &&

   288

		    (ecmd->autoneg != AUTONEG_ENABLE)) {

   289

			e_err("forcing MDI/MDI-X state is not supported when link speed and/or duplex are forced\n");

   290

			return -EINVAL;

   291

		}

   292

	}

   293

   294

	while (test_and_set_bit(__E1000_RESETTING, &adapter->state))

   295

		usleep_range(1000, 2000);

   296

   297

	if (ecmd->autoneg == AUTONEG_ENABLE) {

   298

		hw->mac.autoneg = 1;

   299

		if (hw->phy.media_type == e1000_media_type_fiber)

   300

			hw->phy.autoneg_advertised = ADVERTISED_1000baseT_Full |

   301

						     ADVERTISED_FIBRE |

   302

						     ADVERTISED_Autoneg;

   303

		else

   304

			hw->phy.autoneg_advertised = ecmd->advertising |

   305

						     ADVERTISED_TP |

   306

						     ADVERTISED_Autoneg;

   307

		ecmd->advertising = hw->phy.autoneg_advertised;

   308

		if (adapter->fc_autoneg)

   309

			hw->fc.requested_mode = e1000_fc_default;

   310

	} else {

   311

		u32 speed = ethtool_cmd_speed(ecmd);

   312

		/* calling this overrides forced MDI setting */

   313

		if (e1000_set_spd_dplx(adapter, speed, ecmd->duplex)) {

   314

			clear_bit(__E1000_RESETTING, &adapter->state);

   315

			return -EINVAL;

   316

		}

   317

	}

   318

   319

	/* MDI-X => 2; MDI => 1; Auto => 3 */

   320

	if (ecmd->eth_tp_mdix_ctrl) {

   321

		/* fix up the value for auto (3 => 0) as zero is mapped

   322

		 * internally to auto

   323

		 */

   324

		if (ecmd->eth_tp_mdix_ctrl == ETH_TP_MDI_AUTO)

   325

			hw->phy.mdix = AUTO_ALL_MODES;

   326

		else

   327

			hw->phy.mdix = ecmd->eth_tp_mdix_ctrl;

   328

	}

   329

   330

	/* reset the link */

   331

   332

	if (netif_running(adapter->netdev)) {

   333

		e1000e_down(adapter);

   334

		e1000e_up(adapter);

   335

	} else

   336

		e1000e_reset(adapter);

   337

   338

	clear_bit(__E1000_RESETTING, &adapter->state);

   339

	return 0;

   340

}

   341

   342

static void e1000_get_pauseparam(struct net_device *netdev,

   343

				 struct ethtool_pauseparam *pause)

   344

{

   345

	struct e1000_adapter *adapter = netdev_priv(netdev);

   346

	struct e1000_hw *hw = &adapter->hw;

   347

   348

	pause->autoneg =

   349

		(adapter->fc_autoneg ? AUTONEG_ENABLE : AUTONEG_DISABLE);

   350

   351

	if (hw->fc.current_mode == e1000_fc_rx_pause) {

   352

		pause->rx_pause = 1;

   353

	} else if (hw->fc.current_mode == e1000_fc_tx_pause) {

   354

		pause->tx_pause = 1;

   355

	} else if (hw->fc.current_mode == e1000_fc_full) {

   356

		pause->rx_pause = 1;

   357

		pause->tx_pause = 1;

   358

	}

   359

}

   360

   361

static int e1000_set_pauseparam(struct net_device *netdev,

   362

				struct ethtool_pauseparam *pause)

   363

{

   364

	struct e1000_adapter *adapter = netdev_priv(netdev);

   365

	struct e1000_hw *hw = &adapter->hw;

   366

	int retval = 0;

   367

   368

	adapter->fc_autoneg = pause->autoneg;

   369

   370

	while (test_and_set_bit(__E1000_RESETTING, &adapter->state))

   371

		usleep_range(1000, 2000);

   372

   373

	if (adapter->fc_autoneg == AUTONEG_ENABLE) {

   374

		hw->fc.requested_mode = e1000_fc_default;

   375

		if (netif_running(adapter->netdev)) {

   376

			e1000e_down(adapter);

   377

			e1000e_up(adapter);

   378

		} else {

   379

			e1000e_reset(adapter);

   380

		}

   381

	} else {

   382

		if (pause->rx_pause && pause->tx_pause)

   383

			hw->fc.requested_mode = e1000_fc_full;

   384

		else if (pause->rx_pause && !pause->tx_pause)

   385

			hw->fc.requested_mode = e1000_fc_rx_pause;

   386

		else if (!pause->rx_pause && pause->tx_pause)

   387

			hw->fc.requested_mode = e1000_fc_tx_pause;

   388

		else if (!pause->rx_pause && !pause->tx_pause)

   389

			hw->fc.requested_mode = e1000_fc_none;

   390

   391

		hw->fc.current_mode = hw->fc.requested_mode;

   392

   393

		if (hw->phy.media_type == e1000_media_type_fiber) {

   394

			retval = hw->mac.ops.setup_link(hw);

   395

			/* implicit goto out */

   396

		} else {

   397

			retval = e1000e_force_mac_fc(hw);

   398

			if (retval)

   399

				goto out;

   400

			e1000e_set_fc_watermarks(hw);

   401

		}

   402

	}

   403

   404

out:

   405

	clear_bit(__E1000_RESETTING, &adapter->state);

   406

	return retval;

   407

}

   408

   409

static u32 e1000_get_msglevel(struct net_device *netdev)

   410

{

   411

	struct e1000_adapter *adapter = netdev_priv(netdev);

   412

	return adapter->msg_enable;

   413

}

   414

   415

static void e1000_set_msglevel(struct net_device *netdev, u32 data)

   416

{

   417

	struct e1000_adapter *adapter = netdev_priv(netdev);

   418

	adapter->msg_enable = data;

   419

}

   420

   421

static int e1000_get_regs_len(struct net_device *netdev)

   422

{

   423

#define E1000_REGS_LEN 32 /* overestimate */

   424

	return E1000_REGS_LEN * sizeof(u32);

   425

}

   426

   427

static void e1000_get_regs(struct net_device *netdev,

   428

			   struct ethtool_regs *regs, void *p)

   429

{

   430

	struct e1000_adapter *adapter = netdev_priv(netdev);

   431

	struct e1000_hw *hw = &adapter->hw;

   432

	u32 *regs_buff = p;

   433

	u16 phy_data;

   434

   435

	memset(p, 0, E1000_REGS_LEN * sizeof(u32));

   436

   437

	regs->version = (1 << 24) | (adapter->pdev->revision << 16) |

   438

			adapter->pdev->device;

   439

   440

	regs_buff[0]  = er32(CTRL);

   441

	regs_buff[1]  = er32(STATUS);

   442

   443

	regs_buff[2]  = er32(RCTL);

   444

	regs_buff[3]  = er32(RDLEN(0));

   445

	regs_buff[4]  = er32(RDH(0));

   446

	regs_buff[5]  = er32(RDT(0));

   447

	regs_buff[6]  = er32(RDTR);

   448

   449

	regs_buff[7]  = er32(TCTL);

   450

	regs_buff[8]  = er32(TDLEN(0));

   451

	regs_buff[9]  = er32(TDH(0));

   452

	regs_buff[10] = er32(TDT(0));

   453

	regs_buff[11] = er32(TIDV);

   454

   455

	regs_buff[12] = adapter->hw.phy.type;  /* PHY type (IGP=1, M88=0) */

   456

   457

	/* ethtool doesn't use anything past this point, so all this

   458

	 * code is likely legacy junk for apps that may or may not exist

   459

	 */

   460

	if (hw->phy.type == e1000_phy_m88) {

   461

		e1e_rphy(hw, M88E1000_PHY_SPEC_STATUS, &phy_data);

   462

		regs_buff[13] = (u32)phy_data; /* cable length */

   463

		regs_buff[14] = 0;  /* Dummy (to align w/ IGP phy reg dump) */

   464

		regs_buff[15] = 0;  /* Dummy (to align w/ IGP phy reg dump) */

   465

		regs_buff[16] = 0;  /* Dummy (to align w/ IGP phy reg dump) */

   466

		e1e_rphy(hw, M88E1000_PHY_SPEC_CTRL, &phy_data);

   467

		regs_buff[17] = (u32)phy_data; /* extended 10bt distance */

   468

		regs_buff[18] = regs_buff[13]; /* cable polarity */

   469

		regs_buff[19] = 0;  /* Dummy (to align w/ IGP phy reg dump) */

   470

		regs_buff[20] = regs_buff[17]; /* polarity correction */

   471

		/* phy receive errors */

   472

		regs_buff[22] = adapter->phy_stats.receive_errors;

   473

		regs_buff[23] = regs_buff[13]; /* mdix mode */

   474

	}

   475

	regs_buff[21] = 0; /* was idle_errors */

   476

	e1e_rphy(hw, PHY_1000T_STATUS, &phy_data);

   477

	regs_buff[24] = (u32)phy_data;  /* phy local receiver status */

   478

	regs_buff[25] = regs_buff[24];  /* phy remote receiver status */

   479

}

   480

   481

static int e1000_get_eeprom_len(struct net_device *netdev)

   482

{

   483

	struct e1000_adapter *adapter = netdev_priv(netdev);

   484

	return adapter->hw.nvm.word_size * 2;

   485

}

   486

   487

static int e1000_get_eeprom(struct net_device *netdev,

   488

			    struct ethtool_eeprom *eeprom, u8 *bytes)

   489

{

   490

	struct e1000_adapter *adapter = netdev_priv(netdev);

   491

	struct e1000_hw *hw = &adapter->hw;

   492

	u16 *eeprom_buff;

   493

	int first_word;

   494

	int last_word;

   495

	int ret_val = 0;

   496

	u16 i;

   497

   498

	if (eeprom->len == 0)

   499

		return -EINVAL;

   500

   501

	eeprom->magic = adapter->pdev->vendor | (adapter->pdev->device << 16);

   502

   503

	first_word = eeprom->offset >> 1;

   504

	last_word = (eeprom->offset + eeprom->len - 1) >> 1;

   505

   506

	eeprom_buff = kmalloc(sizeof(u16) *

   507

			(last_word - first_word + 1), GFP_KERNEL);

   508

	if (!eeprom_buff)

   509

		return -ENOMEM;

   510

   511

	if (hw->nvm.type == e1000_nvm_eeprom_spi) {

   512

		ret_val = e1000_read_nvm(hw, first_word,

   513

					 last_word - first_word + 1,

   514

					 eeprom_buff);

   515

	} else {

   516

		for (i = 0; i < last_word - first_word + 1; i++) {

   517

			ret_val = e1000_read_nvm(hw, first_word + i, 1,

   518

						      &eeprom_buff[i]);

   519

			if (ret_val)

   520

				break;

   521

		}

   522

	}

   523

   524

	if (ret_val) {

   525

		/* a read error occurred, throw away the result */

   526

		memset(eeprom_buff, 0xff, sizeof(u16) *

   527

		       (last_word - first_word + 1));

   528

	} else {

   529

		/* Device's eeprom is always little-endian, word addressable */