linux/drivers/net/ethernet/intel/e1000e/mac.c
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   1/* Intel PRO/1000 Linux driver
   2 * Copyright(c) 1999 - 2015 Intel Corporation.
   3 *
   4 * This program is free software; you can redistribute it and/or modify it
   5 * under the terms and conditions of the GNU General Public License,
   6 * version 2, as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope it will be useful, but WITHOUT
   9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11 * more details.
  12 *
  13 * The full GNU General Public License is included in this distribution in
  14 * the file called "COPYING".
  15 *
  16 * Contact Information:
  17 * Linux NICS <linux.nics@intel.com>
  18 * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  19 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  20 */
  21
  22#include "e1000.h"
  23
  24/**
  25 *  e1000e_get_bus_info_pcie - Get PCIe bus information
  26 *  @hw: pointer to the HW structure
  27 *
  28 *  Determines and stores the system bus information for a particular
  29 *  network interface.  The following bus information is determined and stored:
  30 *  bus speed, bus width, type (PCIe), and PCIe function.
  31 **/
  32s32 e1000e_get_bus_info_pcie(struct e1000_hw *hw)
  33{
  34        struct e1000_mac_info *mac = &hw->mac;
  35        struct e1000_bus_info *bus = &hw->bus;
  36        struct e1000_adapter *adapter = hw->adapter;
  37        u16 pcie_link_status, cap_offset;
  38
  39        cap_offset = adapter->pdev->pcie_cap;
  40        if (!cap_offset) {
  41                bus->width = e1000_bus_width_unknown;
  42        } else {
  43                pci_read_config_word(adapter->pdev,
  44                                     cap_offset + PCIE_LINK_STATUS,
  45                                     &pcie_link_status);
  46                bus->width = (enum e1000_bus_width)((pcie_link_status &
  47                                                     PCIE_LINK_WIDTH_MASK) >>
  48                                                    PCIE_LINK_WIDTH_SHIFT);
  49        }
  50
  51        mac->ops.set_lan_id(hw);
  52
  53        return 0;
  54}
  55
  56/**
  57 *  e1000_set_lan_id_multi_port_pcie - Set LAN id for PCIe multiple port devices
  58 *
  59 *  @hw: pointer to the HW structure
  60 *
  61 *  Determines the LAN function id by reading memory-mapped registers
  62 *  and swaps the port value if requested.
  63 **/
  64void e1000_set_lan_id_multi_port_pcie(struct e1000_hw *hw)
  65{
  66        struct e1000_bus_info *bus = &hw->bus;
  67        u32 reg;
  68
  69        /* The status register reports the correct function number
  70         * for the device regardless of function swap state.
  71         */
  72        reg = er32(STATUS);
  73        bus->func = (reg & E1000_STATUS_FUNC_MASK) >> E1000_STATUS_FUNC_SHIFT;
  74}
  75
  76/**
  77 *  e1000_set_lan_id_single_port - Set LAN id for a single port device
  78 *  @hw: pointer to the HW structure
  79 *
  80 *  Sets the LAN function id to zero for a single port device.
  81 **/
  82void e1000_set_lan_id_single_port(struct e1000_hw *hw)
  83{
  84        struct e1000_bus_info *bus = &hw->bus;
  85
  86        bus->func = 0;
  87}
  88
  89/**
  90 *  e1000_clear_vfta_generic - Clear VLAN filter table
  91 *  @hw: pointer to the HW structure
  92 *
  93 *  Clears the register array which contains the VLAN filter table by
  94 *  setting all the values to 0.
  95 **/
  96void e1000_clear_vfta_generic(struct e1000_hw *hw)
  97{
  98        u32 offset;
  99
 100        for (offset = 0; offset < E1000_VLAN_FILTER_TBL_SIZE; offset++) {
 101                E1000_WRITE_REG_ARRAY(hw, E1000_VFTA, offset, 0);
 102                e1e_flush();
 103        }
 104}
 105
 106/**
 107 *  e1000_write_vfta_generic - Write value to VLAN filter table
 108 *  @hw: pointer to the HW structure
 109 *  @offset: register offset in VLAN filter table
 110 *  @value: register value written to VLAN filter table
 111 *
 112 *  Writes value at the given offset in the register array which stores
 113 *  the VLAN filter table.
 114 **/
 115void e1000_write_vfta_generic(struct e1000_hw *hw, u32 offset, u32 value)
 116{
 117        E1000_WRITE_REG_ARRAY(hw, E1000_VFTA, offset, value);
 118        e1e_flush();
 119}
 120
 121/**
 122 *  e1000e_init_rx_addrs - Initialize receive address's
 123 *  @hw: pointer to the HW structure
 124 *  @rar_count: receive address registers
 125 *
 126 *  Setup the receive address registers by setting the base receive address
 127 *  register to the devices MAC address and clearing all the other receive
 128 *  address registers to 0.
 129 **/
 130void e1000e_init_rx_addrs(struct e1000_hw *hw, u16 rar_count)
 131{
 132        u32 i;
 133        u8 mac_addr[ETH_ALEN] = { 0 };
 134
 135        /* Setup the receive address */
 136        e_dbg("Programming MAC Address into RAR[0]\n");
 137
 138        hw->mac.ops.rar_set(hw, hw->mac.addr, 0);
 139
 140        /* Zero out the other (rar_entry_count - 1) receive addresses */
 141        e_dbg("Clearing RAR[1-%u]\n", rar_count - 1);
 142        for (i = 1; i < rar_count; i++)
 143                hw->mac.ops.rar_set(hw, mac_addr, i);
 144}
 145
 146/**
 147 *  e1000_check_alt_mac_addr_generic - Check for alternate MAC addr
 148 *  @hw: pointer to the HW structure
 149 *
 150 *  Checks the nvm for an alternate MAC address.  An alternate MAC address
 151 *  can be setup by pre-boot software and must be treated like a permanent
 152 *  address and must override the actual permanent MAC address. If an
 153 *  alternate MAC address is found it is programmed into RAR0, replacing
 154 *  the permanent address that was installed into RAR0 by the Si on reset.
 155 *  This function will return SUCCESS unless it encounters an error while
 156 *  reading the EEPROM.
 157 **/
 158s32 e1000_check_alt_mac_addr_generic(struct e1000_hw *hw)
 159{
 160        u32 i;
 161        s32 ret_val;
 162        u16 offset, nvm_alt_mac_addr_offset, nvm_data;
 163        u8 alt_mac_addr[ETH_ALEN];
 164
 165        ret_val = e1000_read_nvm(hw, NVM_COMPAT, 1, &nvm_data);
 166        if (ret_val)
 167                return ret_val;
 168
 169        /* not supported on 82573 */
 170        if (hw->mac.type == e1000_82573)
 171                return 0;
 172
 173        ret_val = e1000_read_nvm(hw, NVM_ALT_MAC_ADDR_PTR, 1,
 174                                 &nvm_alt_mac_addr_offset);
 175        if (ret_val) {
 176                e_dbg("NVM Read Error\n");
 177                return ret_val;
 178        }
 179
 180        if ((nvm_alt_mac_addr_offset == 0xFFFF) ||
 181            (nvm_alt_mac_addr_offset == 0x0000))
 182                /* There is no Alternate MAC Address */
 183                return 0;
 184
 185        if (hw->bus.func == E1000_FUNC_1)
 186                nvm_alt_mac_addr_offset += E1000_ALT_MAC_ADDRESS_OFFSET_LAN1;
 187        for (i = 0; i < ETH_ALEN; i += 2) {
 188                offset = nvm_alt_mac_addr_offset + (i >> 1);
 189                ret_val = e1000_read_nvm(hw, offset, 1, &nvm_data);
 190                if (ret_val) {
 191                        e_dbg("NVM Read Error\n");
 192                        return ret_val;
 193                }
 194
 195                alt_mac_addr[i] = (u8)(nvm_data & 0xFF);
 196                alt_mac_addr[i + 1] = (u8)(nvm_data >> 8);
 197        }
 198
 199        /* if multicast bit is set, the alternate address will not be used */
 200        if (is_multicast_ether_addr(alt_mac_addr)) {
 201                e_dbg("Ignoring Alternate Mac Address with MC bit set\n");
 202                return 0;
 203        }
 204
 205        /* We have a valid alternate MAC address, and we want to treat it the
 206         * same as the normal permanent MAC address stored by the HW into the
 207         * RAR. Do this by mapping this address into RAR0.
 208         */
 209        hw->mac.ops.rar_set(hw, alt_mac_addr, 0);
 210
 211        return 0;
 212}
 213
 214u32 e1000e_rar_get_count_generic(struct e1000_hw *hw)
 215{
 216        return hw->mac.rar_entry_count;
 217}
 218
 219/**
 220 *  e1000e_rar_set_generic - Set receive address register
 221 *  @hw: pointer to the HW structure
 222 *  @addr: pointer to the receive address
 223 *  @index: receive address array register
 224 *
 225 *  Sets the receive address array register at index to the address passed
 226 *  in by addr.
 227 **/
 228int e1000e_rar_set_generic(struct e1000_hw *hw, u8 *addr, u32 index)
 229{
 230        u32 rar_low, rar_high;
 231
 232        /* HW expects these in little endian so we reverse the byte order
 233         * from network order (big endian) to little endian
 234         */
 235        rar_low = ((u32)addr[0] | ((u32)addr[1] << 8) |
 236                   ((u32)addr[2] << 16) | ((u32)addr[3] << 24));
 237
 238        rar_high = ((u32)addr[4] | ((u32)addr[5] << 8));
 239
 240        /* If MAC address zero, no need to set the AV bit */
 241        if (rar_low || rar_high)
 242                rar_high |= E1000_RAH_AV;
 243
 244        /* Some bridges will combine consecutive 32-bit writes into
 245         * a single burst write, which will malfunction on some parts.
 246         * The flushes avoid this.
 247         */
 248        ew32(RAL(index), rar_low);
 249        e1e_flush();
 250        ew32(RAH(index), rar_high);
 251        e1e_flush();
 252
 253        return 0;
 254}
 255
 256/**
 257 *  e1000_hash_mc_addr - Generate a multicast hash value
 258 *  @hw: pointer to the HW structure
 259 *  @mc_addr: pointer to a multicast address
 260 *
 261 *  Generates a multicast address hash value which is used to determine
 262 *  the multicast filter table array address and new table value.
 263 **/
 264static u32 e1000_hash_mc_addr(struct e1000_hw *hw, u8 *mc_addr)
 265{
 266        u32 hash_value, hash_mask;
 267        u8 bit_shift = 0;
 268
 269        /* Register count multiplied by bits per register */
 270        hash_mask = (hw->mac.mta_reg_count * 32) - 1;
 271
 272        /* For a mc_filter_type of 0, bit_shift is the number of left-shifts
 273         * where 0xFF would still fall within the hash mask.
 274         */
 275        while (hash_mask >> bit_shift != 0xFF)
 276                bit_shift++;
 277
 278        /* The portion of the address that is used for the hash table
 279         * is determined by the mc_filter_type setting.
 280         * The algorithm is such that there is a total of 8 bits of shifting.
 281         * The bit_shift for a mc_filter_type of 0 represents the number of
 282         * left-shifts where the MSB of mc_addr[5] would still fall within
 283         * the hash_mask.  Case 0 does this exactly.  Since there are a total
 284         * of 8 bits of shifting, then mc_addr[4] will shift right the
 285         * remaining number of bits. Thus 8 - bit_shift.  The rest of the
 286         * cases are a variation of this algorithm...essentially raising the
 287         * number of bits to shift mc_addr[5] left, while still keeping the
 288         * 8-bit shifting total.
 289         *
 290         * For example, given the following Destination MAC Address and an
 291         * mta register count of 128 (thus a 4096-bit vector and 0xFFF mask),
 292         * we can see that the bit_shift for case 0 is 4.  These are the hash
 293         * values resulting from each mc_filter_type...
 294         * [0] [1] [2] [3] [4] [5]
 295         * 01  AA  00  12  34  56
 296         * LSB           MSB
 297         *
 298         * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
 299         * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
 300         * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
 301         * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
 302         */
 303        switch (hw->mac.mc_filter_type) {
 304        default:
 305        case 0:
 306                break;
 307        case 1:
 308                bit_shift += 1;
 309                break;
 310        case 2:
 311                bit_shift += 2;
 312                break;
 313        case 3:
 314                bit_shift += 4;
 315                break;
 316        }
 317
 318        hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
 319                                   (((u16)mc_addr[5]) << bit_shift)));
 320
 321        return hash_value;
 322}
 323
 324/**
 325 *  e1000e_update_mc_addr_list_generic - Update Multicast addresses
 326 *  @hw: pointer to the HW structure
 327 *  @mc_addr_list: array of multicast addresses to program
 328 *  @mc_addr_count: number of multicast addresses to program
 329 *
 330 *  Updates entire Multicast Table Array.
 331 *  The caller must have a packed mc_addr_list of multicast addresses.
 332 **/
 333void e1000e_update_mc_addr_list_generic(struct e1000_hw *hw,
 334                                        u8 *mc_addr_list, u32 mc_addr_count)
 335{
 336        u32 hash_value, hash_bit, hash_reg;
 337        int i;
 338
 339        /* clear mta_shadow */
 340        memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));
 341
 342        /* update mta_shadow from mc_addr_list */
 343        for (i = 0; (u32)i < mc_addr_count; i++) {
 344                hash_value = e1000_hash_mc_addr(hw, mc_addr_list);
 345
 346                hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
 347                hash_bit = hash_value & 0x1F;
 348
 349                hw->mac.mta_shadow[hash_reg] |= BIT(hash_bit);
 350                mc_addr_list += (ETH_ALEN);
 351        }
 352
 353        /* replace the entire MTA table */
 354        for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
 355                E1000_WRITE_REG_ARRAY(hw, E1000_MTA, i, hw->mac.mta_shadow[i]);
 356        e1e_flush();
 357}
 358
 359/**
 360 *  e1000e_clear_hw_cntrs_base - Clear base hardware counters
 361 *  @hw: pointer to the HW structure
 362 *
 363 *  Clears the base hardware counters by reading the counter registers.
 364 **/
 365void e1000e_clear_hw_cntrs_base(struct e1000_hw *hw)
 366{
 367        er32(CRCERRS);
 368        er32(SYMERRS);
 369        er32(MPC);
 370        er32(SCC);
 371        er32(ECOL);
 372        er32(MCC);
 373        er32(LATECOL);
 374        er32(COLC);
 375        er32(DC);
 376        er32(SEC);
 377        er32(RLEC);
 378        er32(XONRXC);
 379        er32(XONTXC);
 380        er32(XOFFRXC);
 381        er32(XOFFTXC);
 382        er32(FCRUC);
 383        er32(GPRC);
 384        er32(BPRC);
 385        er32(MPRC);
 386        er32(GPTC);
 387        er32(GORCL);
 388        er32(GORCH);
 389        er32(GOTCL);
 390        er32(GOTCH);
 391        er32(RNBC);
 392        er32(RUC);
 393        er32(RFC);
 394        er32(ROC);
 395        er32(RJC);
 396        er32(TORL);
 397        er32(TORH);
 398        er32(TOTL);
 399        er32(TOTH);
 400        er32(TPR);
 401        er32(TPT);
 402        er32(MPTC);
 403        er32(BPTC);
 404}
 405
 406/**
 407 *  e1000e_check_for_copper_link - Check for link (Copper)
 408 *  @hw: pointer to the HW structure
 409 *
 410 *  Checks to see of the link status of the hardware has changed.  If a
 411 *  change in link status has been detected, then we read the PHY registers
 412 *  to get the current speed/duplex if link exists.
 413 **/
 414s32 e1000e_check_for_copper_link(struct e1000_hw *hw)
 415{
 416        struct e1000_mac_info *mac = &hw->mac;
 417        s32 ret_val;
 418        bool link;
 419
 420        /* We only want to go out to the PHY registers to see if Auto-Neg
 421         * has completed and/or if our link status has changed.  The
 422         * get_link_status flag is set upon receiving a Link Status
 423         * Change or Rx Sequence Error interrupt.
 424         */
 425        if (!mac->get_link_status)
 426                return 0;
 427
 428        /* First we want to see if the MII Status Register reports
 429         * link.  If so, then we want to get the current speed/duplex
 430         * of the PHY.
 431         */
 432        ret_val = e1000e_phy_has_link_generic(hw, 1, 0, &link);
 433        if (ret_val)
 434                return ret_val;
 435
 436        if (!link)
 437                return 0;       /* No link detected */
 438
 439        mac->get_link_status = false;
 440
 441        /* Check if there was DownShift, must be checked
 442         * immediately after link-up
 443         */
 444        e1000e_check_downshift(hw);
 445
 446        /* If we are forcing speed/duplex, then we simply return since
 447         * we have already determined whether we have link or not.
 448         */
 449        if (!mac->autoneg)
 450                return -E1000_ERR_CONFIG;
 451
 452        /* Auto-Neg is enabled.  Auto Speed Detection takes care
 453         * of MAC speed/duplex configuration.  So we only need to
 454         * configure Collision Distance in the MAC.
 455         */
 456        mac->ops.config_collision_dist(hw);
 457
 458        /* Configure Flow Control now that Auto-Neg has completed.
 459         * First, we need to restore the desired flow control
 460         * settings because we may have had to re-autoneg with a
 461         * different link partner.
 462         */
 463        ret_val = e1000e_config_fc_after_link_up(hw);
 464        if (ret_val)
 465                e_dbg("Error configuring flow control\n");
 466
 467        return ret_val;
 468}
 469
 470/**
 471 *  e1000e_check_for_fiber_link - Check for link (Fiber)
 472 *  @hw: pointer to the HW structure
 473 *
 474 *  Checks for link up on the hardware.  If link is not up and we have
 475 *  a signal, then we need to force link up.
 476 **/
 477s32 e1000e_check_for_fiber_link(struct e1000_hw *hw)
 478{
 479        struct e1000_mac_info *mac = &hw->mac;
 480        u32 rxcw;
 481        u32 ctrl;
 482        u32 status;
 483        s32 ret_val;
 484
 485        ctrl = er32(CTRL);
 486        status = er32(STATUS);
 487        rxcw = er32(RXCW);
 488
 489        /* If we don't have link (auto-negotiation failed or link partner
 490         * cannot auto-negotiate), the cable is plugged in (we have signal),
 491         * and our link partner is not trying to auto-negotiate with us (we
 492         * are receiving idles or data), we need to force link up. We also
 493         * need to give auto-negotiation time to complete, in case the cable
 494         * was just plugged in. The autoneg_failed flag does this.
 495         */
 496        /* (ctrl & E1000_CTRL_SWDPIN1) == 1 == have signal */
 497        if ((ctrl & E1000_CTRL_SWDPIN1) && !(status & E1000_STATUS_LU) &&
 498            !(rxcw & E1000_RXCW_C)) {
 499                if (!mac->autoneg_failed) {
 500                        mac->autoneg_failed = true;
 501                        return 0;
 502                }
 503                e_dbg("NOT Rx'ing /C/, disable AutoNeg and force link.\n");
 504
 505                /* Disable auto-negotiation in the TXCW register */
 506                ew32(TXCW, (mac->txcw & ~E1000_TXCW_ANE));
 507
 508                /* Force link-up and also force full-duplex. */
 509                ctrl = er32(CTRL);
 510                ctrl |= (E1000_CTRL_SLU | E1000_CTRL_FD);
 511                ew32(CTRL, ctrl);
 512
 513                /* Configure Flow Control after forcing link up. */
 514                ret_val = e1000e_config_fc_after_link_up(hw);
 515                if (ret_val) {
 516                        e_dbg("Error configuring flow control\n");
 517                        return ret_val;
 518                }
 519        } else if ((ctrl & E1000_CTRL_SLU) && (rxcw & E1000_RXCW_C)) {
 520                /* If we are forcing link and we are receiving /C/ ordered
 521                 * sets, re-enable auto-negotiation in the TXCW register
 522                 * and disable forced link in the Device Control register
 523                 * in an attempt to auto-negotiate with our link partner.
 524                 */
 525                e_dbg("Rx'ing /C/, enable AutoNeg and stop forcing link.\n");
 526                ew32(TXCW, mac->txcw);
 527                ew32(CTRL, (ctrl & ~E1000_CTRL_SLU));
 528
 529                mac->serdes_has_link = true;
 530        }
 531
 532        return 0;
 533}
 534
 535/**
 536 *  e1000e_check_for_serdes_link - Check for link (Serdes)
 537 *  @hw: pointer to the HW structure
 538 *
 539 *  Checks for link up on the hardware.  If link is not up and we have
 540 *  a signal, then we need to force link up.
 541 **/
 542s32 e1000e_check_for_serdes_link(struct e1000_hw *hw)
 543{
 544        struct e1000_mac_info *mac = &hw->mac;
 545        u32 rxcw;
 546        u32 ctrl;
 547        u32 status;
 548        s32 ret_val;
 549
 550        ctrl = er32(CTRL);
 551        status = er32(STATUS);
 552        rxcw = er32(RXCW);
 553
 554        /* If we don't have link (auto-negotiation failed or link partner
 555         * cannot auto-negotiate), and our link partner is not trying to
 556         * auto-negotiate with us (we are receiving idles or data),
 557         * we need to force link up. We also need to give auto-negotiation
 558         * time to complete.
 559         */
 560        /* (ctrl & E1000_CTRL_SWDPIN1) == 1 == have signal */
 561        if (!(status & E1000_STATUS_LU) && !(rxcw & E1000_RXCW_C)) {
 562                if (!mac->autoneg_failed) {
 563                        mac->autoneg_failed = true;
 564                        return 0;
 565                }
 566                e_dbg("NOT Rx'ing /C/, disable AutoNeg and force link.\n");
 567
 568                /* Disable auto-negotiation in the TXCW register */
 569                ew32(TXCW, (mac->txcw & ~E1000_TXCW_ANE));
 570
 571                /* Force link-up and also force full-duplex. */
 572                ctrl = er32(CTRL);
 573                ctrl |= (E1000_CTRL_SLU | E1000_CTRL_FD);
 574                ew32(CTRL, ctrl);
 575
 576                /* Configure Flow Control after forcing link up. */
 577                ret_val = e1000e_config_fc_after_link_up(hw);
 578                if (ret_val) {
 579                        e_dbg("Error configuring flow control\n");
 580                        return ret_val;
 581                }
 582        } else if ((ctrl & E1000_CTRL_SLU) && (rxcw & E1000_RXCW_C)) {
 583                /* If we are forcing link and we are receiving /C/ ordered
 584                 * sets, re-enable auto-negotiation in the TXCW register
 585                 * and disable forced link in the Device Control register
 586                 * in an attempt to auto-negotiate with our link partner.
 587                 */
 588                e_dbg("Rx'ing /C/, enable AutoNeg and stop forcing link.\n");
 589                ew32(TXCW, mac->txcw);
 590                ew32(CTRL, (ctrl & ~E1000_CTRL_SLU));
 591
 592                mac->serdes_has_link = true;
 593        } else if (!(E1000_TXCW_ANE & er32(TXCW))) {
 594                /* If we force link for non-auto-negotiation switch, check
 595                 * link status based on MAC synchronization for internal
 596                 * serdes media type.
 597                 */
 598                /* SYNCH bit and IV bit are sticky. */
 599                usleep_range(10, 20);
 600                rxcw = er32(RXCW);
 601                if (rxcw & E1000_RXCW_SYNCH) {
 602                        if (!(rxcw & E1000_RXCW_IV)) {
 603                                mac->serdes_has_link = true;
 604                                e_dbg("SERDES: Link up - forced.\n");
 605                        }
 606                } else {
 607                        mac->serdes_has_link = false;
 608                        e_dbg("SERDES: Link down - force failed.\n");
 609                }
 610        }
 611
 612        if (E1000_TXCW_ANE & er32(TXCW)) {
 613                status = er32(STATUS);
 614                if (status & E1000_STATUS_LU) {
 615                        /* SYNCH bit and IV bit are sticky, so reread rxcw. */
 616                        usleep_range(10, 20);
 617                        rxcw = er32(RXCW);
 618                        if (rxcw & E1000_RXCW_SYNCH) {
 619                                if (!(rxcw & E1000_RXCW_IV)) {
 620                                        mac->serdes_has_link = true;
 621                                        e_dbg("SERDES: Link up - autoneg completed successfully.\n");
 622                                } else {
 623                                        mac->serdes_has_link = false;
 624                                        e_dbg("SERDES: Link down - invalid codewords detected in autoneg.\n");
 625                                }
 626                        } else {
 627                                mac->serdes_has_link = false;
 628                                e_dbg("SERDES: Link down - no sync.\n");
 629                        }
 630                } else {
 631                        mac->serdes_has_link = false;
 632                        e_dbg("SERDES: Link down - autoneg failed\n");
 633                }
 634        }
 635
 636        return 0;
 637}
 638
 639/**
 640 *  e1000_set_default_fc_generic - Set flow control default values
 641 *  @hw: pointer to the HW structure
 642 *
 643 *  Read the EEPROM for the default values for flow control and store the
 644 *  values.
 645 **/
 646static s32 e1000_set_default_fc_generic(struct e1000_hw *hw)
 647{
 648        s32 ret_val;
 649        u16 nvm_data;
 650
 651        /* Read and store word 0x0F of the EEPROM. This word contains bits
 652         * that determine the hardware's default PAUSE (flow control) mode,
 653         * a bit that determines whether the HW defaults to enabling or
 654         * disabling auto-negotiation, and the direction of the
 655         * SW defined pins. If there is no SW over-ride of the flow
 656         * control setting, then the variable hw->fc will
 657         * be initialized based on a value in the EEPROM.
 658         */
 659        ret_val = e1000_read_nvm(hw, NVM_INIT_CONTROL2_REG, 1, &nvm_data);
 660
 661        if (ret_val) {
 662                e_dbg("NVM Read Error\n");
 663                return ret_val;
 664        }
 665
 666        if (!(nvm_data & NVM_WORD0F_PAUSE_MASK))
 667                hw->fc.requested_mode = e1000_fc_none;
 668        else if ((nvm_data & NVM_WORD0F_PAUSE_MASK) == NVM_WORD0F_ASM_DIR)
 669                hw->fc.requested_mode = e1000_fc_tx_pause;
 670        else
 671                hw->fc.requested_mode = e1000_fc_full;
 672
 673        return 0;
 674}
 675
 676/**
 677 *  e1000e_setup_link_generic - Setup flow control and link settings
 678 *  @hw: pointer to the HW structure
 679 *
 680 *  Determines which flow control settings to use, then configures flow
 681 *  control.  Calls the appropriate media-specific link configuration
 682 *  function.  Assuming the adapter has a valid link partner, a valid link
 683 *  should be established.  Assumes the hardware has previously been reset
 684 *  and the transmitter and receiver are not enabled.
 685 **/
 686s32 e1000e_setup_link_generic(struct e1000_hw *hw)
 687{
 688        s32 ret_val;
 689
 690        /* In the case of the phy reset being blocked, we already have a link.
 691         * We do not need to set it up again.
 692         */
 693        if (hw->phy.ops.check_reset_block && hw->phy.ops.check_reset_block(hw))
 694                return 0;
 695
 696        /* If requested flow control is set to default, set flow control
 697         * based on the EEPROM flow control settings.
 698         */
 699        if (hw->fc.requested_mode == e1000_fc_default) {
 700                ret_val = e1000_set_default_fc_generic(hw);
 701                if (ret_val)
 702                        return ret_val;
 703        }
 704
 705        /* Save off the requested flow control mode for use later.  Depending
 706         * on the link partner's capabilities, we may or may not use this mode.
 707         */
 708        hw->fc.current_mode = hw->fc.requested_mode;
 709
 710        e_dbg("After fix-ups FlowControl is now = %x\n", hw->fc.current_mode);
 711
 712        /* Call the necessary media_type subroutine to configure the link. */
 713        ret_val = hw->mac.ops.setup_physical_interface(hw);
 714        if (ret_val)
 715                return ret_val;
 716
 717        /* Initialize the flow control address, type, and PAUSE timer
 718         * registers to their default values.  This is done even if flow
 719         * control is disabled, because it does not hurt anything to
 720         * initialize these registers.
 721         */
 722        e_dbg("Initializing the Flow Control address, type and timer regs\n");
 723        ew32(FCT, FLOW_CONTROL_TYPE);
 724        ew32(FCAH, FLOW_CONTROL_ADDRESS_HIGH);
 725        ew32(FCAL, FLOW_CONTROL_ADDRESS_LOW);
 726
 727        ew32(FCTTV, hw->fc.pause_time);
 728
 729        return e1000e_set_fc_watermarks(hw);
 730}
 731
 732/**
 733 *  e1000_commit_fc_settings_generic - Configure flow control
 734 *  @hw: pointer to the HW structure
 735 *
 736 *  Write the flow control settings to the Transmit Config Word Register (TXCW)
 737 *  base on the flow control settings in e1000_mac_info.
 738 **/
 739static s32 e1000_commit_fc_settings_generic(struct e1000_hw *hw)
 740{
 741        struct e1000_mac_info *mac = &hw->mac;
 742        u32 txcw;
 743
 744        /* Check for a software override of the flow control settings, and
 745         * setup the device accordingly.  If auto-negotiation is enabled, then
 746         * software will have to set the "PAUSE" bits to the correct value in
 747         * the Transmit Config Word Register (TXCW) and re-start auto-
 748         * negotiation.  However, if auto-negotiation is disabled, then
 749         * software will have to manually configure the two flow control enable
 750         * bits in the CTRL register.
 751         *
 752         * The possible values of the "fc" parameter are:
 753         *      0:  Flow control is completely disabled
 754         *      1:  Rx flow control is enabled (we can receive pause frames,
 755         *          but not send pause frames).
 756         *      2:  Tx flow control is enabled (we can send pause frames but we
 757         *          do not support receiving pause frames).
 758         *      3:  Both Rx and Tx flow control (symmetric) are enabled.
 759         */
 760        switch (hw->fc.current_mode) {
 761        case e1000_fc_none:
 762                /* Flow control completely disabled by a software over-ride. */
 763                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD);
 764                break;
 765        case e1000_fc_rx_pause:
 766                /* Rx Flow control is enabled and Tx Flow control is disabled
 767                 * by a software over-ride. Since there really isn't a way to
 768                 * advertise that we are capable of Rx Pause ONLY, we will
 769                 * advertise that we support both symmetric and asymmetric Rx
 770                 * PAUSE.  Later, we will disable the adapter's ability to send
 771                 * PAUSE frames.
 772                 */
 773                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_PAUSE_MASK);
 774                break;
 775        case e1000_fc_tx_pause:
 776                /* Tx Flow control is enabled, and Rx Flow control is disabled,
 777                 * by a software over-ride.
 778                 */
 779                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_ASM_DIR);
 780                break;
 781        case e1000_fc_full:
 782                /* Flow control (both Rx and Tx) is enabled by a software
 783                 * over-ride.
 784                 */
 785                txcw = (E1000_TXCW_ANE | E1000_TXCW_FD | E1000_TXCW_PAUSE_MASK);
 786                break;
 787        default:
 788                e_dbg("Flow control param set incorrectly\n");
 789                return -E1000_ERR_CONFIG;
 790        }
 791
 792        ew32(TXCW, txcw);
 793        mac->txcw = txcw;
 794
 795        return 0;
 796}
 797
 798/**
 799 *  e1000_poll_fiber_serdes_link_generic - Poll for link up
 800 *  @hw: pointer to the HW structure
 801 *
 802 *  Polls for link up by reading the status register, if link fails to come
 803 *  up with auto-negotiation, then the link is forced if a signal is detected.
 804 **/
 805static s32 e1000_poll_fiber_serdes_link_generic(struct e1000_hw *hw)
 806{
 807        struct e1000_mac_info *mac = &hw->mac;
 808        u32 i, status;
 809        s32 ret_val;
 810
 811        /* If we have a signal (the cable is plugged in, or assumed true for
 812         * serdes media) then poll for a "Link-Up" indication in the Device
 813         * Status Register.  Time-out if a link isn't seen in 500 milliseconds
 814         * seconds (Auto-negotiation should complete in less than 500
 815         * milliseconds even if the other end is doing it in SW).
 816         */
 817        for (i = 0; i < FIBER_LINK_UP_LIMIT; i++) {
 818                usleep_range(10000, 20000);
 819                status = er32(STATUS);
 820                if (status & E1000_STATUS_LU)
 821                        break;
 822        }
 823        if (i == FIBER_LINK_UP_LIMIT) {
 824                e_dbg("Never got a valid link from auto-neg!!!\n");
 825                mac->autoneg_failed = true;
 826                /* AutoNeg failed to achieve a link, so we'll call
 827                 * mac->check_for_link. This routine will force the
 828                 * link up if we detect a signal. This will allow us to
 829                 * communicate with non-autonegotiating link partners.
 830                 */
 831                ret_val = mac->ops.check_for_link(hw);
 832                if (ret_val) {
 833                        e_dbg("Error while checking for link\n");
 834                        return ret_val;
 835                }
 836                mac->autoneg_failed = false;
 837        } else {
 838                mac->autoneg_failed = false;
 839                e_dbg("Valid Link Found\n");
 840        }
 841
 842        return 0;
 843}
 844
 845/**
 846 *  e1000e_setup_fiber_serdes_link - Setup link for fiber/serdes
 847 *  @hw: pointer to the HW structure
 848 *
 849 *  Configures collision distance and flow control for fiber and serdes
 850 *  links.  Upon successful setup, poll for link.
 851 **/
 852s32 e1000e_setup_fiber_serdes_link(struct e1000_hw *hw)
 853{
 854        u32 ctrl;
 855        s32 ret_val;
 856
 857        ctrl = er32(CTRL);
 858
 859        /* Take the link out of reset */
 860        ctrl &= ~E1000_CTRL_LRST;
 861
 862        hw->mac.ops.config_collision_dist(hw);
 863
 864        ret_val = e1000_commit_fc_settings_generic(hw);
 865        if (ret_val)
 866                return ret_val;
 867
 868        /* Since auto-negotiation is enabled, take the link out of reset (the
 869         * link will be in reset, because we previously reset the chip). This
 870         * will restart auto-negotiation.  If auto-negotiation is successful
 871         * then the link-up status bit will be set and the flow control enable
 872         * bits (RFCE and TFCE) will be set according to their negotiated value.
 873         */
 874        e_dbg("Auto-negotiation enabled\n");
 875
 876        ew32(CTRL, ctrl);
 877        e1e_flush();
 878        usleep_range(1000, 2000);
 879
 880        /* For these adapters, the SW definable pin 1 is set when the optics
 881         * detect a signal.  If we have a signal, then poll for a "Link-Up"
 882         * indication.
 883         */
 884        if (hw->phy.media_type == e1000_media_type_internal_serdes ||
 885            (er32(CTRL) & E1000_CTRL_SWDPIN1)) {
 886                ret_val = e1000_poll_fiber_serdes_link_generic(hw);
 887        } else {
 888                e_dbg("No signal detected\n");
 889        }
 890
 891        return ret_val;
 892}
 893
 894/**
 895 *  e1000e_config_collision_dist_generic - Configure collision distance
 896 *  @hw: pointer to the HW structure
 897 *
 898 *  Configures the collision distance to the default value and is used
 899 *  during link setup.
 900 **/
 901void e1000e_config_collision_dist_generic(struct e1000_hw *hw)
 902{
 903        u32 tctl;
 904
 905        tctl = er32(TCTL);
 906
 907        tctl &= ~E1000_TCTL_COLD;
 908        tctl |= E1000_COLLISION_DISTANCE << E1000_COLD_SHIFT;
 909
 910        ew32(TCTL, tctl);
 911        e1e_flush();
 912}
 913
 914/**
 915 *  e1000e_set_fc_watermarks - Set flow control high/low watermarks
 916 *  @hw: pointer to the HW structure
 917 *
 918 *  Sets the flow control high/low threshold (watermark) registers.  If
 919 *  flow control XON frame transmission is enabled, then set XON frame
 920 *  transmission as well.
 921 **/
 922s32 e1000e_set_fc_watermarks(struct e1000_hw *hw)
 923{
 924        u32 fcrtl = 0, fcrth = 0;
 925
 926        /* Set the flow control receive threshold registers.  Normally,
 927         * these registers will be set to a default threshold that may be
 928         * adjusted later by the driver's runtime code.  However, if the
 929         * ability to transmit pause frames is not enabled, then these
 930         * registers will be set to 0.
 931         */
 932        if (hw->fc.current_mode & e1000_fc_tx_pause) {
 933                /* We need to set up the Receive Threshold high and low water
 934                 * marks as well as (optionally) enabling the transmission of
 935                 * XON frames.
 936                 */
 937                fcrtl = hw->fc.low_water;
 938                if (hw->fc.send_xon)
 939                        fcrtl |= E1000_FCRTL_XONE;
 940
 941                fcrth = hw->fc.high_water;
 942        }
 943        ew32(FCRTL, fcrtl);
 944        ew32(FCRTH, fcrth);
 945
 946        return 0;
 947}
 948
 949/**
 950 *  e1000e_force_mac_fc - Force the MAC's flow control settings
 951 *  @hw: pointer to the HW structure
 952 *
 953 *  Force the MAC's flow control settings.  Sets the TFCE and RFCE bits in the
 954 *  device control register to reflect the adapter settings.  TFCE and RFCE
 955 *  need to be explicitly set by software when a copper PHY is used because
 956 *  autonegotiation is managed by the PHY rather than the MAC.  Software must
 957 *  also configure these bits when link is forced on a fiber connection.
 958 **/
 959s32 e1000e_force_mac_fc(struct e1000_hw *hw)
 960{
 961        u32 ctrl;
 962
 963        ctrl = er32(CTRL);
 964
 965        /* Because we didn't get link via the internal auto-negotiation
 966         * mechanism (we either forced link or we got link via PHY
 967         * auto-neg), we have to manually enable/disable transmit an
 968         * receive flow control.
 969         *
 970         * The "Case" statement below enables/disable flow control
 971         * according to the "hw->fc.current_mode" parameter.
 972         *
 973         * The possible values of the "fc" parameter are:
 974         *      0:  Flow control is completely disabled
 975         *      1:  Rx flow control is enabled (we can receive pause
 976         *          frames but not send pause frames).
 977         *      2:  Tx flow control is enabled (we can send pause frames
 978         *          frames but we do not receive pause frames).
 979         *      3:  Both Rx and Tx flow control (symmetric) is enabled.
 980         *  other:  No other values should be possible at this point.
 981         */
 982        e_dbg("hw->fc.current_mode = %u\n", hw->fc.current_mode);
 983
 984        switch (hw->fc.current_mode) {
 985        case e1000_fc_none:
 986                ctrl &= (~(E1000_CTRL_TFCE | E1000_CTRL_RFCE));
 987                break;
 988        case e1000_fc_rx_pause:
 989                ctrl &= (~E1000_CTRL_TFCE);
 990                ctrl |= E1000_CTRL_RFCE;
 991                break;
 992        case e1000_fc_tx_pause:
 993                ctrl &= (~E1000_CTRL_RFCE);
 994                ctrl |= E1000_CTRL_TFCE;
 995                break;
 996        case e1000_fc_full:
 997                ctrl |= (E1000_CTRL_TFCE | E1000_CTRL_RFCE);
 998                break;
 999        default:
1000                e_dbg("Flow control param set incorrectly\n");
1001                return -E1000_ERR_CONFIG;
1002        }
1003
1004        ew32(CTRL, ctrl);
1005
1006        return 0;
1007}
1008
1009/**
1010 *  e1000e_config_fc_after_link_up - Configures flow control after link
1011 *  @hw: pointer to the HW structure
1012 *
1013 *  Checks the status of auto-negotiation after link up to ensure that the
1014 *  speed and duplex were not forced.  If the link needed to be forced, then
1015 *  flow control needs to be forced also.  If auto-negotiation is enabled
1016 *  and did not fail, then we configure flow control based on our link
1017 *  partner.
1018 **/
1019s32 e1000e_config_fc_after_link_up(struct e1000_hw *hw)
1020{
1021        struct e1000_mac_info *mac = &hw->mac;
1022        s32 ret_val = 0;
1023        u32 pcs_status_reg, pcs_adv_reg, pcs_lp_ability_reg, pcs_ctrl_reg;
1024        u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg;
1025        u16 speed, duplex;
1026
1027        /* Check for the case where we have fiber media and auto-neg failed
1028         * so we had to force link.  In this case, we need to force the
1029         * configuration of the MAC to match the "fc" parameter.
1030         */
1031        if (mac->autoneg_failed) {
1032                if (hw->phy.media_type == e1000_media_type_fiber ||
1033                    hw->phy.media_type == e1000_media_type_internal_serdes)
1034                        ret_val = e1000e_force_mac_fc(hw);
1035        } else {
1036                if (hw->phy.media_type == e1000_media_type_copper)
1037                        ret_val = e1000e_force_mac_fc(hw);
1038        }
1039
1040        if (ret_val) {
1041                e_dbg("Error forcing flow control settings\n");
1042                return ret_val;
1043        }
1044
1045        /* Check for the case where we have copper media and auto-neg is
1046         * enabled.  In this case, we need to check and see if Auto-Neg
1047         * has completed, and if so, how the PHY and link partner has
1048         * flow control configured.
1049         */
1050        if ((hw->phy.media_type == e1000_media_type_copper) && mac->autoneg) {
1051                /* Read the MII Status Register and check to see if AutoNeg
1052                 * has completed.  We read this twice because this reg has
1053                 * some "sticky" (latched) bits.
1054                 */
1055                ret_val = e1e_rphy(hw, MII_BMSR, &mii_status_reg);
1056                if (ret_val)
1057                        return ret_val;
1058                ret_val = e1e_rphy(hw, MII_BMSR, &mii_status_reg);
1059                if (ret_val)
1060                        return ret_val;
1061
1062                if (!(mii_status_reg & BMSR_ANEGCOMPLETE)) {
1063                        e_dbg("Copper PHY and Auto Neg has not completed.\n");
1064                        return ret_val;
1065                }
1066
1067                /* The AutoNeg process has completed, so we now need to
1068                 * read both the Auto Negotiation Advertisement
1069                 * Register (Address 4) and the Auto_Negotiation Base
1070                 * Page Ability Register (Address 5) to determine how
1071                 * flow control was negotiated.
1072                 */
1073                ret_val = e1e_rphy(hw, MII_ADVERTISE, &mii_nway_adv_reg);
1074                if (ret_val)
1075                        return ret_val;
1076                ret_val = e1e_rphy(hw, MII_LPA, &mii_nway_lp_ability_reg);
1077                if (ret_val)
1078                        return ret_val;
1079
1080                /* Two bits in the Auto Negotiation Advertisement Register
1081                 * (Address 4) and two bits in the Auto Negotiation Base
1082                 * Page Ability Register (Address 5) determine flow control
1083                 * for both the PHY and the link partner.  The following
1084                 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
1085                 * 1999, describes these PAUSE resolution bits and how flow
1086                 * control is determined based upon these settings.
1087                 * NOTE:  DC = Don't Care
1088                 *
1089                 *   LOCAL DEVICE  |   LINK PARTNER
1090                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
1091                 *-------|---------|-------|---------|--------------------
1092                 *   0   |    0    |  DC   |   DC    | e1000_fc_none
1093                 *   0   |    1    |   0   |   DC    | e1000_fc_none
1094                 *   0   |    1    |   1   |    0    | e1000_fc_none
1095                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1096                 *   1   |    0    |   0   |   DC    | e1000_fc_none
1097                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1098                 *   1   |    1    |   0   |    0    | e1000_fc_none
1099                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1100                 *
1101                 * Are both PAUSE bits set to 1?  If so, this implies
1102                 * Symmetric Flow Control is enabled at both ends.  The
1103                 * ASM_DIR bits are irrelevant per the spec.
1104                 *
1105                 * For Symmetric Flow Control:
1106                 *
1107                 *   LOCAL DEVICE  |   LINK PARTNER
1108                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1109                 *-------|---------|-------|---------|--------------------
1110                 *   1   |   DC    |   1   |   DC    | E1000_fc_full
1111                 *
1112                 */
1113                if ((mii_nway_adv_reg & ADVERTISE_PAUSE_CAP) &&
1114                    (mii_nway_lp_ability_reg & LPA_PAUSE_CAP)) {
1115                        /* Now we need to check if the user selected Rx ONLY
1116                         * of pause frames.  In this case, we had to advertise
1117                         * FULL flow control because we could not advertise Rx
1118                         * ONLY. Hence, we must now check to see if we need to
1119                         * turn OFF the TRANSMISSION of PAUSE frames.
1120                         */
1121                        if (hw->fc.requested_mode == e1000_fc_full) {
1122                                hw->fc.current_mode = e1000_fc_full;
1123                                e_dbg("Flow Control = FULL.\n");
1124                        } else {
1125                                hw->fc.current_mode = e1000_fc_rx_pause;
1126                                e_dbg("Flow Control = Rx PAUSE frames only.\n");
1127                        }
1128                }
1129                /* For receiving PAUSE frames ONLY.
1130                 *
1131                 *   LOCAL DEVICE  |   LINK PARTNER
1132                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1133                 *-------|---------|-------|---------|--------------------
1134                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1135                 */
1136                else if (!(mii_nway_adv_reg & ADVERTISE_PAUSE_CAP) &&
1137                         (mii_nway_adv_reg & ADVERTISE_PAUSE_ASYM) &&
1138                         (mii_nway_lp_ability_reg & LPA_PAUSE_CAP) &&
1139                         (mii_nway_lp_ability_reg & LPA_PAUSE_ASYM)) {
1140                        hw->fc.current_mode = e1000_fc_tx_pause;
1141                        e_dbg("Flow Control = Tx PAUSE frames only.\n");
1142                }
1143                /* For transmitting PAUSE frames ONLY.
1144                 *
1145                 *   LOCAL DEVICE  |   LINK PARTNER
1146                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1147                 *-------|---------|-------|---------|--------------------
1148                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1149                 */
1150                else if ((mii_nway_adv_reg & ADVERTISE_PAUSE_CAP) &&
1151                         (mii_nway_adv_reg & ADVERTISE_PAUSE_ASYM) &&
1152                         !(mii_nway_lp_ability_reg & LPA_PAUSE_CAP) &&
1153                         (mii_nway_lp_ability_reg & LPA_PAUSE_ASYM)) {
1154                        hw->fc.current_mode = e1000_fc_rx_pause;
1155                        e_dbg("Flow Control = Rx PAUSE frames only.\n");
1156                } else {
1157                        /* Per the IEEE spec, at this point flow control
1158                         * should be disabled.
1159                         */
1160                        hw->fc.current_mode = e1000_fc_none;
1161                        e_dbg("Flow Control = NONE.\n");
1162                }
1163
1164                /* Now we need to do one last check...  If we auto-
1165                 * negotiated to HALF DUPLEX, flow control should not be
1166                 * enabled per IEEE 802.3 spec.
1167                 */
1168                ret_val = mac->ops.get_link_up_info(hw, &speed, &duplex);
1169                if (ret_val) {
1170                        e_dbg("Error getting link speed and duplex\n");
1171                        return ret_val;
1172                }
1173
1174                if (duplex == HALF_DUPLEX)
1175                        hw->fc.current_mode = e1000_fc_none;
1176
1177                /* Now we call a subroutine to actually force the MAC
1178                 * controller to use the correct flow control settings.
1179                 */
1180                ret_val = e1000e_force_mac_fc(hw);
1181                if (ret_val) {
1182                        e_dbg("Error forcing flow control settings\n");
1183                        return ret_val;
1184                }
1185        }
1186
1187        /* Check for the case where we have SerDes media and auto-neg is
1188         * enabled.  In this case, we need to check and see if Auto-Neg
1189         * has completed, and if so, how the PHY and link partner has
1190         * flow control configured.
1191         */
1192        if ((hw->phy.media_type == e1000_media_type_internal_serdes) &&
1193            mac->autoneg) {
1194                /* Read the PCS_LSTS and check to see if AutoNeg
1195                 * has completed.
1196                 */
1197                pcs_status_reg = er32(PCS_LSTAT);
1198
1199                if (!(pcs_status_reg & E1000_PCS_LSTS_AN_COMPLETE)) {
1200                        e_dbg("PCS Auto Neg has not completed.\n");
1201                        return ret_val;
1202                }
1203
1204                /* The AutoNeg process has completed, so we now need to
1205                 * read both the Auto Negotiation Advertisement
1206                 * Register (PCS_ANADV) and the Auto_Negotiation Base
1207                 * Page Ability Register (PCS_LPAB) to determine how
1208                 * flow control was negotiated.
1209                 */
1210                pcs_adv_reg = er32(PCS_ANADV);
1211                pcs_lp_ability_reg = er32(PCS_LPAB);
1212
1213                /* Two bits in the Auto Negotiation Advertisement Register
1214                 * (PCS_ANADV) and two bits in the Auto Negotiation Base
1215                 * Page Ability Register (PCS_LPAB) determine flow control
1216                 * for both the PHY and the link partner.  The following
1217                 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
1218                 * 1999, describes these PAUSE resolution bits and how flow
1219                 * control is determined based upon these settings.
1220                 * NOTE:  DC = Don't Care
1221                 *
1222                 *   LOCAL DEVICE  |   LINK PARTNER
1223                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
1224                 *-------|---------|-------|---------|--------------------
1225                 *   0   |    0    |  DC   |   DC    | e1000_fc_none
1226                 *   0   |    1    |   0   |   DC    | e1000_fc_none
1227                 *   0   |    1    |   1   |    0    | e1000_fc_none
1228                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1229                 *   1   |    0    |   0   |   DC    | e1000_fc_none
1230                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1231                 *   1   |    1    |   0   |    0    | e1000_fc_none
1232                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1233                 *
1234                 * Are both PAUSE bits set to 1?  If so, this implies
1235                 * Symmetric Flow Control is enabled at both ends.  The
1236                 * ASM_DIR bits are irrelevant per the spec.
1237                 *
1238                 * For Symmetric Flow Control:
1239                 *
1240                 *   LOCAL DEVICE  |   LINK PARTNER
1241                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1242                 *-------|---------|-------|---------|--------------------
1243                 *   1   |   DC    |   1   |   DC    | e1000_fc_full
1244                 *
1245                 */
1246                if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
1247                    (pcs_lp_ability_reg & E1000_TXCW_PAUSE)) {
1248                        /* Now we need to check if the user selected Rx ONLY
1249                         * of pause frames.  In this case, we had to advertise
1250                         * FULL flow control because we could not advertise Rx
1251                         * ONLY. Hence, we must now check to see if we need to
1252                         * turn OFF the TRANSMISSION of PAUSE frames.
1253                         */
1254                        if (hw->fc.requested_mode == e1000_fc_full) {
1255                                hw->fc.current_mode = e1000_fc_full;
1256                                e_dbg("Flow Control = FULL.\n");
1257                        } else {
1258                                hw->fc.current_mode = e1000_fc_rx_pause;
1259                                e_dbg("Flow Control = Rx PAUSE frames only.\n");
1260                        }
1261                }
1262                /* For receiving PAUSE frames ONLY.
1263                 *
1264                 *   LOCAL DEVICE  |   LINK PARTNER
1265                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1266                 *-------|---------|-------|---------|--------------------
1267                 *   0   |    1    |   1   |    1    | e1000_fc_tx_pause
1268                 */
1269                else if (!(pcs_adv_reg & E1000_TXCW_PAUSE) &&
1270                         (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
1271                         (pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
1272                         (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
1273                        hw->fc.current_mode = e1000_fc_tx_pause;
1274                        e_dbg("Flow Control = Tx PAUSE frames only.\n");
1275                }
1276                /* For transmitting PAUSE frames ONLY.
1277                 *
1278                 *   LOCAL DEVICE  |   LINK PARTNER
1279                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
1280                 *-------|---------|-------|---------|--------------------
1281                 *   1   |    1    |   0   |    1    | e1000_fc_rx_pause
1282                 */
1283                else if ((pcs_adv_reg & E1000_TXCW_PAUSE) &&
1284                         (pcs_adv_reg & E1000_TXCW_ASM_DIR) &&
1285                         !(pcs_lp_ability_reg & E1000_TXCW_PAUSE) &&
1286                         (pcs_lp_ability_reg & E1000_TXCW_ASM_DIR)) {
1287                        hw->fc.current_mode = e1000_fc_rx_pause;
1288                        e_dbg("Flow Control = Rx PAUSE frames only.\n");
1289                } else {
1290                        /* Per the IEEE spec, at this point flow control
1291                         * should be disabled.
1292                         */
1293                        hw->fc.current_mode = e1000_fc_none;
1294                        e_dbg("Flow Control = NONE.\n");
1295                }
1296
1297                /* Now we call a subroutine to actually force the MAC
1298                 * controller to use the correct flow control settings.
1299                 */
1300                pcs_ctrl_reg = er32(PCS_LCTL);
1301                pcs_ctrl_reg |= E1000_PCS_LCTL_FORCE_FCTRL;
1302                ew32(PCS_LCTL, pcs_ctrl_reg);
1303
1304                ret_val = e1000e_force_mac_fc(hw);
1305                if (ret_val) {
1306                        e_dbg("Error forcing flow control settings\n");
1307                        return ret_val;
1308                }
1309        }
1310
1311        return 0;
1312}
1313
1314/**
1315 *  e1000e_get_speed_and_duplex_copper - Retrieve current speed/duplex
1316 *  @hw: pointer to the HW structure
1317 *  @speed: stores the current speed
1318 *  @duplex: stores the current duplex
1319 *
1320 *  Read the status register for the current speed/duplex and store the current
1321 *  speed and duplex for copper connections.
1322 **/
1323s32 e1000e_get_speed_and_duplex_copper(struct e1000_hw *hw, u16 *speed,
1324                                       u16 *duplex)
1325{
1326        u32 status;
1327
1328        status = er32(STATUS);
1329        if (status & E1000_STATUS_SPEED_1000)
1330                *speed = SPEED_1000;
1331        else if (status & E1000_STATUS_SPEED_100)
1332                *speed = SPEED_100;
1333        else
1334                *speed = SPEED_10;
1335
1336        if (status & E1000_STATUS_FD)
1337                *duplex = FULL_DUPLEX;
1338        else
1339                *duplex = HALF_DUPLEX;
1340
1341        e_dbg("%u Mbps, %s Duplex\n",
1342              *speed == SPEED_1000 ? 1000 : *speed == SPEED_100 ? 100 : 10,
1343              *duplex == FULL_DUPLEX ? "Full" : "Half");
1344
1345        return 0;
1346}
1347
1348/**
1349 *  e1000e_get_speed_and_duplex_fiber_serdes - Retrieve current speed/duplex
1350 *  @hw: pointer to the HW structure
1351 *  @speed: stores the current speed
1352 *  @duplex: stores the current duplex
1353 *
1354 *  Sets the speed and duplex to gigabit full duplex (the only possible option)
1355 *  for fiber/serdes links.
1356 **/
1357s32 e1000e_get_speed_and_duplex_fiber_serdes(struct e1000_hw __always_unused
1358                                             *hw, u16 *speed, u16 *duplex)
1359{
1360        *speed = SPEED_1000;
1361        *duplex = FULL_DUPLEX;
1362
1363        return 0;
1364}
1365
1366/**
1367 *  e1000e_get_hw_semaphore - Acquire hardware semaphore
1368 *  @hw: pointer to the HW structure
1369 *
1370 *  Acquire the HW semaphore to access the PHY or NVM
1371 **/
1372s32 e1000e_get_hw_semaphore(struct e1000_hw *hw)
1373{
1374        u32 swsm;
1375        s32 timeout = hw->nvm.word_size + 1;
1376        s32 i = 0;
1377
1378        /* Get the SW semaphore */
1379        while (i < timeout) {
1380                swsm = er32(SWSM);
1381                if (!(swsm & E1000_SWSM_SMBI))
1382                        break;
1383
1384                usleep_range(50, 100);
1385                i++;
1386        }
1387
1388        if (i == timeout) {
1389                e_dbg("Driver can't access device - SMBI bit is set.\n");
1390                return -E1000_ERR_NVM;
1391        }
1392
1393        /* Get the FW semaphore. */
1394        for (i = 0; i < timeout; i++) {
1395                swsm = er32(SWSM);
1396                ew32(SWSM, swsm | E1000_SWSM_SWESMBI);
1397
1398                /* Semaphore acquired if bit latched */
1399                if (er32(SWSM) & E1000_SWSM_SWESMBI)
1400                        break;
1401
1402                usleep_range(50, 100);
1403        }
1404
1405        if (i == timeout) {
1406                /* Release semaphores */
1407                e1000e_put_hw_semaphore(hw);
1408                e_dbg("Driver can't access the NVM\n");
1409                return -E1000_ERR_NVM;
1410        }
1411
1412        return 0;
1413}
1414
1415/**
1416 *  e1000e_put_hw_semaphore - Release hardware semaphore
1417 *  @hw: pointer to the HW structure
1418 *
1419 *  Release hardware semaphore used to access the PHY or NVM
1420 **/
1421void e1000e_put_hw_semaphore(struct e1000_hw *hw)
1422{
1423        u32 swsm;
1424
1425        swsm = er32(SWSM);
1426        swsm &= ~(E1000_SWSM_SMBI | E1000_SWSM_SWESMBI);
1427        ew32(SWSM, swsm);
1428}
1429
1430/**
1431 *  e1000e_get_auto_rd_done - Check for auto read completion
1432 *  @hw: pointer to the HW structure
1433 *
1434 *  Check EEPROM for Auto Read done bit.
1435 **/
1436s32 e1000e_get_auto_rd_done(struct e1000_hw *hw)
1437{
1438        s32 i = 0;
1439
1440        while (i < AUTO_READ_DONE_TIMEOUT) {
1441                if (er32(EECD) & E1000_EECD_AUTO_RD)
1442                        break;
1443                usleep_range(1000, 2000);
1444                i++;
1445        }
1446
1447        if (i == AUTO_READ_DONE_TIMEOUT) {
1448                e_dbg("Auto read by HW from NVM has not completed.\n");
1449                return -E1000_ERR_RESET;
1450        }
1451
1452        return 0;
1453}
1454
1455/**
1456 *  e1000e_valid_led_default - Verify a valid default LED config
1457 *  @hw: pointer to the HW structure
1458 *  @data: pointer to the NVM (EEPROM)
1459 *
1460 *  Read the EEPROM for the current default LED configuration.  If the
1461 *  LED configuration is not valid, set to a valid LED configuration.
1462 **/
1463s32 e1000e_valid_led_default(struct e1000_hw *hw, u16 *data)
1464{
1465        s32 ret_val;
1466
1467        ret_val = e1000_read_nvm(hw, NVM_ID_LED_SETTINGS, 1, data);
1468        if (ret_val) {
1469                e_dbg("NVM Read Error\n");
1470                return ret_val;
1471        }
1472
1473        if (*data == ID_LED_RESERVED_0000 || *data == ID_LED_RESERVED_FFFF)
1474                *data = ID_LED_DEFAULT;
1475
1476        return 0;
1477}
1478
1479/**
1480 *  e1000e_id_led_init_generic -
1481 *  @hw: pointer to the HW structure
1482 *
1483 **/
1484s32 e1000e_id_led_init_generic(struct e1000_hw *hw)
1485{
1486        struct e1000_mac_info *mac = &hw->mac;
1487        s32 ret_val;
1488        const u32 ledctl_mask = 0x000000FF;
1489        const u32 ledctl_on = E1000_LEDCTL_MODE_LED_ON;
1490        const u32 ledctl_off = E1000_LEDCTL_MODE_LED_OFF;
1491        u16 data, i, temp;
1492        const u16 led_mask = 0x0F;
1493
1494        ret_val = hw->nvm.ops.valid_led_default(hw, &data);
1495        if (ret_val)
1496                return ret_val;
1497
1498        mac->ledctl_default = er32(LEDCTL);
1499        mac->ledctl_mode1 = mac->ledctl_default;
1500        mac->ledctl_mode2 = mac->ledctl_default;
1501
1502        for (i = 0; i < 4; i++) {
1503                temp = (data >> (i << 2)) & led_mask;
1504                switch (temp) {
1505                case ID_LED_ON1_DEF2:
1506                case ID_LED_ON1_ON2:
1507                case ID_LED_ON1_OFF2:
1508                        mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
1509                        mac->ledctl_mode1 |= ledctl_on << (i << 3);
1510                        break;
1511                case ID_LED_OFF1_DEF2:
1512                case ID_LED_OFF1_ON2:
1513                case ID_LED_OFF1_OFF2:
1514                        mac->ledctl_mode1 &= ~(ledctl_mask << (i << 3));
1515                        mac->ledctl_mode1 |= ledctl_off << (i << 3);
1516                        break;
1517                default:
1518                        /* Do nothing */
1519                        break;
1520                }
1521                switch (temp) {
1522                case ID_LED_DEF1_ON2:
1523                case ID_LED_ON1_ON2:
1524                case ID_LED_OFF1_ON2:
1525                        mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
1526                        mac->ledctl_mode2 |= ledctl_on << (i << 3);
1527                        break;
1528                case ID_LED_DEF1_OFF2:
1529                case ID_LED_ON1_OFF2:
1530                case ID_LED_OFF1_OFF2:
1531                        mac->ledctl_mode2 &= ~(ledctl_mask << (i << 3));
1532                        mac->ledctl_mode2 |= ledctl_off << (i << 3);
1533                        break;
1534                default:
1535                        /* Do nothing */
1536                        break;
1537                }
1538        }
1539
1540        return 0;
1541}
1542
1543/**
1544 *  e1000e_setup_led_generic - Configures SW controllable LED
1545 *  @hw: pointer to the HW structure
1546 *
1547 *  This prepares the SW controllable LED for use and saves the current state
1548 *  of the LED so it can be later restored.
1549 **/
1550s32 e1000e_setup_led_generic(struct e1000_hw *hw)
1551{
1552        u32 ledctl;
1553
1554        if (hw->mac.ops.setup_led != e1000e_setup_led_generic)
1555                return -E1000_ERR_CONFIG;
1556
1557        if (hw->phy.media_type == e1000_media_type_fiber) {
1558                ledctl = er32(LEDCTL);
1559                hw->mac.ledctl_default = ledctl;
1560                /* Turn off LED0 */
1561                ledctl &= ~(E1000_LEDCTL_LED0_IVRT | E1000_LEDCTL_LED0_BLINK |
1562                            E1000_LEDCTL_LED0_MODE_MASK);
1563                ledctl |= (E1000_LEDCTL_MODE_LED_OFF <<
1564                           E1000_LEDCTL_LED0_MODE_SHIFT);
1565                ew32(LEDCTL, ledctl);
1566        } else if (hw->phy.media_type == e1000_media_type_copper) {
1567                ew32(LEDCTL, hw->mac.ledctl_mode1);
1568        }
1569
1570        return 0;
1571}
1572
1573/**
1574 *  e1000e_cleanup_led_generic - Set LED config to default operation
1575 *  @hw: pointer to the HW structure
1576 *
1577 *  Remove the current LED configuration and set the LED configuration
1578 *  to the default value, saved from the EEPROM.
1579 **/
1580s32 e1000e_cleanup_led_generic(struct e1000_hw *hw)
1581{
1582        ew32(LEDCTL, hw->mac.ledctl_default);
1583        return 0;
1584}
1585
1586/**
1587 *  e1000e_blink_led_generic - Blink LED
1588 *  @hw: pointer to the HW structure
1589 *
1590 *  Blink the LEDs which are set to be on.
1591 **/
1592s32 e1000e_blink_led_generic(struct e1000_hw *hw)
1593{
1594        u32 ledctl_blink = 0;
1595        u32 i;
1596
1597        if (hw->phy.media_type == e1000_media_type_fiber) {
1598                /* always blink LED0 for PCI-E fiber */
1599                ledctl_blink = E1000_LEDCTL_LED0_BLINK |
1600                    (E1000_LEDCTL_MODE_LED_ON << E1000_LEDCTL_LED0_MODE_SHIFT);
1601        } else {
1602                /* Set the blink bit for each LED that's "on" (0x0E)
1603                 * (or "off" if inverted) in ledctl_mode2.  The blink
1604                 * logic in hardware only works when mode is set to "on"
1605                 * so it must be changed accordingly when the mode is
1606                 * "off" and inverted.
1607                 */
1608                ledctl_blink = hw->mac.ledctl_mode2;
1609                for (i = 0; i < 32; i += 8) {
1610                        u32 mode = (hw->mac.ledctl_mode2 >> i) &
1611                            E1000_LEDCTL_LED0_MODE_MASK;
1612                        u32 led_default = hw->mac.ledctl_default >> i;
1613
1614                        if ((!(led_default & E1000_LEDCTL_LED0_IVRT) &&
1615                             (mode == E1000_LEDCTL_MODE_LED_ON)) ||
1616                            ((led_default & E1000_LEDCTL_LED0_IVRT) &&
1617                             (mode == E1000_LEDCTL_MODE_LED_OFF))) {
1618                                ledctl_blink &=
1619                                    ~(E1000_LEDCTL_LED0_MODE_MASK << i);
1620                                ledctl_blink |= (E1000_LEDCTL_LED0_BLINK |
1621                                                 E1000_LEDCTL_MODE_LED_ON) << i;
1622                        }
1623                }
1624        }
1625
1626        ew32(LEDCTL, ledctl_blink);
1627
1628        return 0;
1629}
1630
1631/**
1632 *  e1000e_led_on_generic - Turn LED on
1633 *  @hw: pointer to the HW structure
1634 *
1635 *  Turn LED on.
1636 **/
1637s32 e1000e_led_on_generic(struct e1000_hw *hw)
1638{
1639        u32 ctrl;
1640
1641        switch (hw->phy.media_type) {
1642        case e1000_media_type_fiber:
1643                ctrl = er32(CTRL);
1644                ctrl &= ~E1000_CTRL_SWDPIN0;
1645                ctrl |= E1000_CTRL_SWDPIO0;
1646                ew32(CTRL, ctrl);
1647                break;
1648        case e1000_media_type_copper:
1649                ew32(LEDCTL, hw->mac.ledctl_mode2);
1650                break;
1651        default:
1652                break;
1653        }
1654
1655        return 0;
1656}
1657
1658/**
1659 *  e1000e_led_off_generic - Turn LED off
1660 *  @hw: pointer to the HW structure
1661 *
1662 *  Turn LED off.
1663 **/
1664s32 e1000e_led_off_generic(struct e1000_hw *hw)
1665{
1666        u32 ctrl;
1667
1668        switch (hw->phy.media_type) {
1669        case e1000_media_type_fiber:
1670                ctrl = er32(CTRL);
1671                ctrl |= E1000_CTRL_SWDPIN0;
1672                ctrl |= E1000_CTRL_SWDPIO0;
1673                ew32(CTRL, ctrl);
1674                break;
1675        case e1000_media_type_copper:
1676                ew32(LEDCTL, hw->mac.ledctl_mode1);
1677                break;
1678        default:
1679                break;
1680        }
1681
1682        return 0;
1683}
1684
1685/**
1686 *  e1000e_set_pcie_no_snoop - Set PCI-express capabilities
1687 *  @hw: pointer to the HW structure
1688 *  @no_snoop: bitmap of snoop events
1689 *
1690 *  Set the PCI-express register to snoop for events enabled in 'no_snoop'.
1691 **/
1692void e1000e_set_pcie_no_snoop(struct e1000_hw *hw, u32 no_snoop)
1693{
1694        u32 gcr;
1695
1696        if (no_snoop) {
1697                gcr = er32(GCR);
1698                gcr &= ~(PCIE_NO_SNOOP_ALL);
1699                gcr |= no_snoop;
1700                ew32(GCR, gcr);
1701        }
1702}
1703
1704/**
1705 *  e1000e_disable_pcie_master - Disables PCI-express master access
1706 *  @hw: pointer to the HW structure
1707 *
1708 *  Returns 0 if successful, else returns -10
1709 *  (-E1000_ERR_MASTER_REQUESTS_PENDING) if master disable bit has not caused
1710 *  the master requests to be disabled.
1711 *
1712 *  Disables PCI-Express master access and verifies there are no pending
1713 *  requests.
1714 **/
1715s32 e1000e_disable_pcie_master(struct e1000_hw *hw)
1716{
1717        u32 ctrl;
1718        s32 timeout = MASTER_DISABLE_TIMEOUT;
1719
1720        ctrl = er32(CTRL);
1721        ctrl |= E1000_CTRL_GIO_MASTER_DISABLE;
1722        ew32(CTRL, ctrl);
1723
1724        while (timeout) {
1725                if (!(er32(STATUS) & E1000_STATUS_GIO_MASTER_ENABLE))
1726                        break;
1727                usleep_range(100, 200);
1728                timeout--;
1729        }
1730
1731        if (!timeout) {
1732                e_dbg("Master requests are pending.\n");
1733                return -E1000_ERR_MASTER_REQUESTS_PENDING;
1734        }
1735
1736        return 0;
1737}
1738
1739/**
1740 *  e1000e_reset_adaptive - Reset Adaptive Interframe Spacing
1741 *  @hw: pointer to the HW structure
1742 *
1743 *  Reset the Adaptive Interframe Spacing throttle to default values.
1744 **/
1745void e1000e_reset_adaptive(struct e1000_hw *hw)
1746{
1747        struct e1000_mac_info *mac = &hw->mac;
1748
1749        if (!mac->adaptive_ifs) {
1750                e_dbg("Not in Adaptive IFS mode!\n");
1751                return;
1752        }
1753
1754        mac->current_ifs_val = 0;
1755        mac->ifs_min_val = IFS_MIN;
1756        mac->ifs_max_val = IFS_MAX;
1757        mac->ifs_step_size = IFS_STEP;
1758        mac->ifs_ratio = IFS_RATIO;
1759
1760        mac->in_ifs_mode = false;
1761        ew32(AIT, 0);
1762}
1763
1764/**
1765 *  e1000e_update_adaptive - Update Adaptive Interframe Spacing
1766 *  @hw: pointer to the HW structure
1767 *
1768 *  Update the Adaptive Interframe Spacing Throttle value based on the
1769 *  time between transmitted packets and time between collisions.
1770 **/
1771void e1000e_update_adaptive(struct e1000_hw *hw)
1772{
1773        struct e1000_mac_info *mac = &hw->mac;
1774
1775        if (!mac->adaptive_ifs) {
1776                e_dbg("Not in Adaptive IFS mode!\n");
1777                return;
1778        }
1779
1780        if ((mac->collision_delta * mac->ifs_ratio) > mac->tx_packet_delta) {
1781                if (mac->tx_packet_delta > MIN_NUM_XMITS) {
1782                        mac->in_ifs_mode = true;
1783                        if (mac->current_ifs_val < mac->ifs_max_val) {
1784                                if (!mac->current_ifs_val)
1785                                        mac->current_ifs_val = mac->ifs_min_val;
1786                                else
1787                                        mac->current_ifs_val +=
1788                                            mac->ifs_step_size;
1789                                ew32(AIT, mac->current_ifs_val);
1790                        }
1791                }
1792        } else {
1793                if (mac->in_ifs_mode &&
1794                    (mac->tx_packet_delta <= MIN_NUM_XMITS)) {
1795                        mac->current_ifs_val = 0;
1796                        mac->in_ifs_mode = false;
1797                        ew32(AIT, 0);
1798                }
1799        }
1800}
1801