linux/drivers/net/ethernet/intel/igc/igc_mac.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (c)  2018 Intel Corporation */
   3
   4#include <linux/pci.h>
   5#include <linux/delay.h>
   6
   7#include "igc_mac.h"
   8#include "igc_hw.h"
   9
  10/**
  11 * igc_disable_pcie_master - Disables PCI-express master access
  12 * @hw: pointer to the HW structure
  13 *
  14 * Returns 0 (0) if successful, else returns -10
  15 * (-IGC_ERR_MASTER_REQUESTS_PENDING) if master disable bit has not caused
  16 * the master requests to be disabled.
  17 *
  18 * Disables PCI-Express master access and verifies there are no pending
  19 * requests.
  20 */
  21s32 igc_disable_pcie_master(struct igc_hw *hw)
  22{
  23        s32 timeout = MASTER_DISABLE_TIMEOUT;
  24        s32 ret_val = 0;
  25        u32 ctrl;
  26
  27        ctrl = rd32(IGC_CTRL);
  28        ctrl |= IGC_CTRL_GIO_MASTER_DISABLE;
  29        wr32(IGC_CTRL, ctrl);
  30
  31        while (timeout) {
  32                if (!(rd32(IGC_STATUS) &
  33                    IGC_STATUS_GIO_MASTER_ENABLE))
  34                        break;
  35                usleep_range(2000, 3000);
  36                timeout--;
  37        }
  38
  39        if (!timeout) {
  40                hw_dbg("Master requests are pending.\n");
  41                ret_val = -IGC_ERR_MASTER_REQUESTS_PENDING;
  42                goto out;
  43        }
  44
  45out:
  46        return ret_val;
  47}
  48
  49/**
  50 * igc_init_rx_addrs - Initialize receive addresses
  51 * @hw: pointer to the HW structure
  52 * @rar_count: receive address registers
  53 *
  54 * Setup the receive address registers by setting the base receive address
  55 * register to the devices MAC address and clearing all the other receive
  56 * address registers to 0.
  57 */
  58void igc_init_rx_addrs(struct igc_hw *hw, u16 rar_count)
  59{
  60        u8 mac_addr[ETH_ALEN] = {0};
  61        u32 i;
  62
  63        /* Setup the receive address */
  64        hw_dbg("Programming MAC Address into RAR[0]\n");
  65
  66        hw->mac.ops.rar_set(hw, hw->mac.addr, 0);
  67
  68        /* Zero out the other (rar_entry_count - 1) receive addresses */
  69        hw_dbg("Clearing RAR[1-%u]\n", rar_count - 1);
  70        for (i = 1; i < rar_count; i++)
  71                hw->mac.ops.rar_set(hw, mac_addr, i);
  72}
  73
  74/**
  75 * igc_set_fc_watermarks - Set flow control high/low watermarks
  76 * @hw: pointer to the HW structure
  77 *
  78 * Sets the flow control high/low threshold (watermark) registers.  If
  79 * flow control XON frame transmission is enabled, then set XON frame
  80 * transmission as well.
  81 */
  82static s32 igc_set_fc_watermarks(struct igc_hw *hw)
  83{
  84        u32 fcrtl = 0, fcrth = 0;
  85
  86        /* Set the flow control receive threshold registers.  Normally,
  87         * these registers will be set to a default threshold that may be
  88         * adjusted later by the driver's runtime code.  However, if the
  89         * ability to transmit pause frames is not enabled, then these
  90         * registers will be set to 0.
  91         */
  92        if (hw->fc.current_mode & igc_fc_tx_pause) {
  93                /* We need to set up the Receive Threshold high and low water
  94                 * marks as well as (optionally) enabling the transmission of
  95                 * XON frames.
  96                 */
  97                fcrtl = hw->fc.low_water;
  98                if (hw->fc.send_xon)
  99                        fcrtl |= IGC_FCRTL_XONE;
 100
 101                fcrth = hw->fc.high_water;
 102        }
 103        wr32(IGC_FCRTL, fcrtl);
 104        wr32(IGC_FCRTH, fcrth);
 105
 106        return 0;
 107}
 108
 109/**
 110 * igc_setup_link - Setup flow control and link settings
 111 * @hw: pointer to the HW structure
 112 *
 113 * Determines which flow control settings to use, then configures flow
 114 * control.  Calls the appropriate media-specific link configuration
 115 * function.  Assuming the adapter has a valid link partner, a valid link
 116 * should be established.  Assumes the hardware has previously been reset
 117 * and the transmitter and receiver are not enabled.
 118 */
 119s32 igc_setup_link(struct igc_hw *hw)
 120{
 121        s32 ret_val = 0;
 122
 123        /* In the case of the phy reset being blocked, we already have a link.
 124         * We do not need to set it up again.
 125         */
 126        if (igc_check_reset_block(hw))
 127                goto out;
 128
 129        /* If requested flow control is set to default, set flow control
 130         * to the both 'rx' and 'tx' pause frames.
 131         */
 132        if (hw->fc.requested_mode == igc_fc_default)
 133                hw->fc.requested_mode = igc_fc_full;
 134
 135        /* We want to save off the original Flow Control configuration just
 136         * in case we get disconnected and then reconnected into a different
 137         * hub or switch with different Flow Control capabilities.
 138         */
 139        hw->fc.current_mode = hw->fc.requested_mode;
 140
 141        hw_dbg("After fix-ups FlowControl is now = %x\n", hw->fc.current_mode);
 142
 143        /* Call the necessary media_type subroutine to configure the link. */
 144        ret_val = hw->mac.ops.setup_physical_interface(hw);
 145        if (ret_val)
 146                goto out;
 147
 148        /* Initialize the flow control address, type, and PAUSE timer
 149         * registers to their default values.  This is done even if flow
 150         * control is disabled, because it does not hurt anything to
 151         * initialize these registers.
 152         */
 153        hw_dbg("Initializing the Flow Control address, type and timer regs\n");
 154        wr32(IGC_FCT, FLOW_CONTROL_TYPE);
 155        wr32(IGC_FCAH, FLOW_CONTROL_ADDRESS_HIGH);
 156        wr32(IGC_FCAL, FLOW_CONTROL_ADDRESS_LOW);
 157
 158        wr32(IGC_FCTTV, hw->fc.pause_time);
 159
 160        ret_val = igc_set_fc_watermarks(hw);
 161
 162out:
 163        return ret_val;
 164}
 165
 166/**
 167 * igc_force_mac_fc - Force the MAC's flow control settings
 168 * @hw: pointer to the HW structure
 169 *
 170 * Force the MAC's flow control settings.  Sets the TFCE and RFCE bits in the
 171 * device control register to reflect the adapter settings.  TFCE and RFCE
 172 * need to be explicitly set by software when a copper PHY is used because
 173 * autonegotiation is managed by the PHY rather than the MAC.  Software must
 174 * also configure these bits when link is forced on a fiber connection.
 175 */
 176s32 igc_force_mac_fc(struct igc_hw *hw)
 177{
 178        s32 ret_val = 0;
 179        u32 ctrl;
 180
 181        ctrl = rd32(IGC_CTRL);
 182
 183        /* Because we didn't get link via the internal auto-negotiation
 184         * mechanism (we either forced link or we got link via PHY
 185         * auto-neg), we have to manually enable/disable transmit an
 186         * receive flow control.
 187         *
 188         * The "Case" statement below enables/disable flow control
 189         * according to the "hw->fc.current_mode" parameter.
 190         *
 191         * The possible values of the "fc" parameter are:
 192         *      0:  Flow control is completely disabled
 193         *      1:  Rx flow control is enabled (we can receive pause
 194         *          frames but not send pause frames).
 195         *      2:  Tx flow control is enabled (we can send pause frames
 196         *          frames but we do not receive pause frames).
 197         *      3:  Both Rx and TX flow control (symmetric) is enabled.
 198         *  other:  No other values should be possible at this point.
 199         */
 200        hw_dbg("hw->fc.current_mode = %u\n", hw->fc.current_mode);
 201
 202        switch (hw->fc.current_mode) {
 203        case igc_fc_none:
 204                ctrl &= (~(IGC_CTRL_TFCE | IGC_CTRL_RFCE));
 205                break;
 206        case igc_fc_rx_pause:
 207                ctrl &= (~IGC_CTRL_TFCE);
 208                ctrl |= IGC_CTRL_RFCE;
 209                break;
 210        case igc_fc_tx_pause:
 211                ctrl &= (~IGC_CTRL_RFCE);
 212                ctrl |= IGC_CTRL_TFCE;
 213                break;
 214        case igc_fc_full:
 215                ctrl |= (IGC_CTRL_TFCE | IGC_CTRL_RFCE);
 216                break;
 217        default:
 218                hw_dbg("Flow control param set incorrectly\n");
 219                ret_val = -IGC_ERR_CONFIG;
 220                goto out;
 221        }
 222
 223        wr32(IGC_CTRL, ctrl);
 224
 225out:
 226        return ret_val;
 227}
 228
 229/**
 230 * igc_clear_hw_cntrs_base - Clear base hardware counters
 231 * @hw: pointer to the HW structure
 232 *
 233 * Clears the base hardware counters by reading the counter registers.
 234 */
 235void igc_clear_hw_cntrs_base(struct igc_hw *hw)
 236{
 237        rd32(IGC_CRCERRS);
 238        rd32(IGC_MPC);
 239        rd32(IGC_SCC);
 240        rd32(IGC_ECOL);
 241        rd32(IGC_MCC);
 242        rd32(IGC_LATECOL);
 243        rd32(IGC_COLC);
 244        rd32(IGC_RERC);
 245        rd32(IGC_DC);
 246        rd32(IGC_RLEC);
 247        rd32(IGC_XONRXC);
 248        rd32(IGC_XONTXC);
 249        rd32(IGC_XOFFRXC);
 250        rd32(IGC_XOFFTXC);
 251        rd32(IGC_FCRUC);
 252        rd32(IGC_GPRC);
 253        rd32(IGC_BPRC);
 254        rd32(IGC_MPRC);
 255        rd32(IGC_GPTC);
 256        rd32(IGC_GORCL);
 257        rd32(IGC_GORCH);
 258        rd32(IGC_GOTCL);
 259        rd32(IGC_GOTCH);
 260        rd32(IGC_RNBC);
 261        rd32(IGC_RUC);
 262        rd32(IGC_RFC);
 263        rd32(IGC_ROC);
 264        rd32(IGC_RJC);
 265        rd32(IGC_TORL);
 266        rd32(IGC_TORH);
 267        rd32(IGC_TOTL);
 268        rd32(IGC_TOTH);
 269        rd32(IGC_TPR);
 270        rd32(IGC_TPT);
 271        rd32(IGC_MPTC);
 272        rd32(IGC_BPTC);
 273
 274        rd32(IGC_PRC64);
 275        rd32(IGC_PRC127);
 276        rd32(IGC_PRC255);
 277        rd32(IGC_PRC511);
 278        rd32(IGC_PRC1023);
 279        rd32(IGC_PRC1522);
 280        rd32(IGC_PTC64);
 281        rd32(IGC_PTC127);
 282        rd32(IGC_PTC255);
 283        rd32(IGC_PTC511);
 284        rd32(IGC_PTC1023);
 285        rd32(IGC_PTC1522);
 286
 287        rd32(IGC_ALGNERRC);
 288        rd32(IGC_RXERRC);
 289        rd32(IGC_TNCRS);
 290        rd32(IGC_HTDPMC);
 291        rd32(IGC_TSCTC);
 292
 293        rd32(IGC_MGTPRC);
 294        rd32(IGC_MGTPDC);
 295        rd32(IGC_MGTPTC);
 296
 297        rd32(IGC_IAC);
 298
 299        rd32(IGC_RPTHC);
 300        rd32(IGC_TLPIC);
 301        rd32(IGC_RLPIC);
 302        rd32(IGC_HGPTC);
 303        rd32(IGC_RXDMTC);
 304        rd32(IGC_HGORCL);
 305        rd32(IGC_HGORCH);
 306        rd32(IGC_HGOTCL);
 307        rd32(IGC_HGOTCH);
 308        rd32(IGC_LENERRS);
 309}
 310
 311/**
 312 * igc_rar_set - Set receive address register
 313 * @hw: pointer to the HW structure
 314 * @addr: pointer to the receive address
 315 * @index: receive address array register
 316 *
 317 * Sets the receive address array register at index to the address passed
 318 * in by addr.
 319 */
 320void igc_rar_set(struct igc_hw *hw, u8 *addr, u32 index)
 321{
 322        u32 rar_low, rar_high;
 323
 324        /* HW expects these in little endian so we reverse the byte order
 325         * from network order (big endian) to little endian
 326         */
 327        rar_low = ((u32)addr[0] |
 328                   ((u32)addr[1] << 8) |
 329                   ((u32)addr[2] << 16) | ((u32)addr[3] << 24));
 330
 331        rar_high = ((u32)addr[4] | ((u32)addr[5] << 8));
 332
 333        /* If MAC address zero, no need to set the AV bit */
 334        if (rar_low || rar_high)
 335                rar_high |= IGC_RAH_AV;
 336
 337        /* Some bridges will combine consecutive 32-bit writes into
 338         * a single burst write, which will malfunction on some parts.
 339         * The flushes avoid this.
 340         */
 341        wr32(IGC_RAL(index), rar_low);
 342        wrfl();
 343        wr32(IGC_RAH(index), rar_high);
 344        wrfl();
 345}
 346
 347/**
 348 * igc_check_for_copper_link - Check for link (Copper)
 349 * @hw: pointer to the HW structure
 350 *
 351 * Checks to see of the link status of the hardware has changed.  If a
 352 * change in link status has been detected, then we read the PHY registers
 353 * to get the current speed/duplex if link exists.
 354 */
 355s32 igc_check_for_copper_link(struct igc_hw *hw)
 356{
 357        struct igc_mac_info *mac = &hw->mac;
 358        bool link = false;
 359        s32 ret_val;
 360
 361        /* We only want to go out to the PHY registers to see if Auto-Neg
 362         * has completed and/or if our link status has changed.  The
 363         * get_link_status flag is set upon receiving a Link Status
 364         * Change or Rx Sequence Error interrupt.
 365         */
 366        if (!mac->get_link_status) {
 367                ret_val = 0;
 368                goto out;
 369        }
 370
 371        /* First we want to see if the MII Status Register reports
 372         * link.  If so, then we want to get the current speed/duplex
 373         * of the PHY.
 374         */
 375        ret_val = igc_phy_has_link(hw, 1, 0, &link);
 376        if (ret_val)
 377                goto out;
 378
 379        if (!link)
 380                goto out; /* No link detected */
 381
 382        mac->get_link_status = false;
 383
 384        /* Check if there was DownShift, must be checked
 385         * immediately after link-up
 386         */
 387        igc_check_downshift(hw);
 388
 389        /* If we are forcing speed/duplex, then we simply return since
 390         * we have already determined whether we have link or not.
 391         */
 392        if (!mac->autoneg) {
 393                ret_val = -IGC_ERR_CONFIG;
 394                goto out;
 395        }
 396
 397        /* Auto-Neg is enabled.  Auto Speed Detection takes care
 398         * of MAC speed/duplex configuration.  So we only need to
 399         * configure Collision Distance in the MAC.
 400         */
 401        igc_config_collision_dist(hw);
 402
 403        /* Configure Flow Control now that Auto-Neg has completed.
 404         * First, we need to restore the desired flow control
 405         * settings because we may have had to re-autoneg with a
 406         * different link partner.
 407         */
 408        ret_val = igc_config_fc_after_link_up(hw);
 409        if (ret_val)
 410                hw_dbg("Error configuring flow control\n");
 411
 412out:
 413        /* Now that we are aware of our link settings, we can set the LTR
 414         * thresholds.
 415         */
 416        ret_val = igc_set_ltr_i225(hw, link);
 417
 418        return ret_val;
 419}
 420
 421/**
 422 * igc_config_collision_dist - Configure collision distance
 423 * @hw: pointer to the HW structure
 424 *
 425 * Configures the collision distance to the default value and is used
 426 * during link setup. Currently no func pointer exists and all
 427 * implementations are handled in the generic version of this function.
 428 */
 429void igc_config_collision_dist(struct igc_hw *hw)
 430{
 431        u32 tctl;
 432
 433        tctl = rd32(IGC_TCTL);
 434
 435        tctl &= ~IGC_TCTL_COLD;
 436        tctl |= IGC_COLLISION_DISTANCE << IGC_COLD_SHIFT;
 437
 438        wr32(IGC_TCTL, tctl);
 439        wrfl();
 440}
 441
 442/**
 443 * igc_config_fc_after_link_up - Configures flow control after link
 444 * @hw: pointer to the HW structure
 445 *
 446 * Checks the status of auto-negotiation after link up to ensure that the
 447 * speed and duplex were not forced.  If the link needed to be forced, then
 448 * flow control needs to be forced also.  If auto-negotiation is enabled
 449 * and did not fail, then we configure flow control based on our link
 450 * partner.
 451 */
 452s32 igc_config_fc_after_link_up(struct igc_hw *hw)
 453{
 454        u16 mii_status_reg, mii_nway_adv_reg, mii_nway_lp_ability_reg;
 455        struct igc_mac_info *mac = &hw->mac;
 456        u16 speed, duplex;
 457        s32 ret_val = 0;
 458
 459        /* Check for the case where we have fiber media and auto-neg failed
 460         * so we had to force link.  In this case, we need to force the
 461         * configuration of the MAC to match the "fc" parameter.
 462         */
 463        if (mac->autoneg_failed)
 464                ret_val = igc_force_mac_fc(hw);
 465
 466        if (ret_val) {
 467                hw_dbg("Error forcing flow control settings\n");
 468                goto out;
 469        }
 470
 471        /* Check for the case where we have copper media and auto-neg is
 472         * enabled.  In this case, we need to check and see if Auto-Neg
 473         * has completed, and if so, how the PHY and link partner has
 474         * flow control configured.
 475         */
 476        if (mac->autoneg) {
 477                /* Read the MII Status Register and check to see if AutoNeg
 478                 * has completed.  We read this twice because this reg has
 479                 * some "sticky" (latched) bits.
 480                 */
 481                ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
 482                                               &mii_status_reg);
 483                if (ret_val)
 484                        goto out;
 485                ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS,
 486                                               &mii_status_reg);
 487                if (ret_val)
 488                        goto out;
 489
 490                if (!(mii_status_reg & MII_SR_AUTONEG_COMPLETE)) {
 491                        hw_dbg("Copper PHY and Auto Neg has not completed.\n");
 492                        goto out;
 493                }
 494
 495                /* The AutoNeg process has completed, so we now need to
 496                 * read both the Auto Negotiation Advertisement
 497                 * Register (Address 4) and the Auto_Negotiation Base
 498                 * Page Ability Register (Address 5) to determine how
 499                 * flow control was negotiated.
 500                 */
 501                ret_val = hw->phy.ops.read_reg(hw, PHY_AUTONEG_ADV,
 502                                               &mii_nway_adv_reg);
 503                if (ret_val)
 504                        goto out;
 505                ret_val = hw->phy.ops.read_reg(hw, PHY_LP_ABILITY,
 506                                               &mii_nway_lp_ability_reg);
 507                if (ret_val)
 508                        goto out;
 509                /* Two bits in the Auto Negotiation Advertisement Register
 510                 * (Address 4) and two bits in the Auto Negotiation Base
 511                 * Page Ability Register (Address 5) determine flow control
 512                 * for both the PHY and the link partner.  The following
 513                 * table, taken out of the IEEE 802.3ab/D6.0 dated March 25,
 514                 * 1999, describes these PAUSE resolution bits and how flow
 515                 * control is determined based upon these settings.
 516                 * NOTE:  DC = Don't Care
 517                 *
 518                 *   LOCAL DEVICE  |   LINK PARTNER
 519                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | NIC Resolution
 520                 *-------|---------|-------|---------|--------------------
 521                 *   0   |    0    |  DC   |   DC    | igc_fc_none
 522                 *   0   |    1    |   0   |   DC    | igc_fc_none
 523                 *   0   |    1    |   1   |    0    | igc_fc_none
 524                 *   0   |    1    |   1   |    1    | igc_fc_tx_pause
 525                 *   1   |    0    |   0   |   DC    | igc_fc_none
 526                 *   1   |   DC    |   1   |   DC    | igc_fc_full
 527                 *   1   |    1    |   0   |    0    | igc_fc_none
 528                 *   1   |    1    |   0   |    1    | igc_fc_rx_pause
 529                 *
 530                 * Are both PAUSE bits set to 1?  If so, this implies
 531                 * Symmetric Flow Control is enabled at both ends.  The
 532                 * ASM_DIR bits are irrelevant per the spec.
 533                 *
 534                 * For Symmetric Flow Control:
 535                 *
 536                 *   LOCAL DEVICE  |   LINK PARTNER
 537                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
 538                 *-------|---------|-------|---------|--------------------
 539                 *   1   |   DC    |   1   |   DC    | IGC_fc_full
 540                 *
 541                 */
 542                if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
 543                    (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE)) {
 544                        /* Now we need to check if the user selected RX ONLY
 545                         * of pause frames.  In this case, we had to advertise
 546                         * FULL flow control because we could not advertise RX
 547                         * ONLY. Hence, we must now check to see if we need to
 548                         * turn OFF  the TRANSMISSION of PAUSE frames.
 549                         */
 550                        if (hw->fc.requested_mode == igc_fc_full) {
 551                                hw->fc.current_mode = igc_fc_full;
 552                                hw_dbg("Flow Control = FULL.\n");
 553                        } else {
 554                                hw->fc.current_mode = igc_fc_rx_pause;
 555                                hw_dbg("Flow Control = RX PAUSE frames only.\n");
 556                        }
 557                }
 558
 559                /* For receiving PAUSE frames ONLY.
 560                 *
 561                 *   LOCAL DEVICE  |   LINK PARTNER
 562                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
 563                 *-------|---------|-------|---------|--------------------
 564                 *   0   |    1    |   1   |    1    | igc_fc_tx_pause
 565                 */
 566                else if (!(mii_nway_adv_reg & NWAY_AR_PAUSE) &&
 567                         (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
 568                         (mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
 569                         (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
 570                        hw->fc.current_mode = igc_fc_tx_pause;
 571                        hw_dbg("Flow Control = TX PAUSE frames only.\n");
 572                }
 573                /* For transmitting PAUSE frames ONLY.
 574                 *
 575                 *   LOCAL DEVICE  |   LINK PARTNER
 576                 * PAUSE | ASM_DIR | PAUSE | ASM_DIR | Result
 577                 *-------|---------|-------|---------|--------------------
 578                 *   1   |    1    |   0   |    1    | igc_fc_rx_pause
 579                 */
 580                else if ((mii_nway_adv_reg & NWAY_AR_PAUSE) &&
 581                         (mii_nway_adv_reg & NWAY_AR_ASM_DIR) &&
 582                         !(mii_nway_lp_ability_reg & NWAY_LPAR_PAUSE) &&
 583                         (mii_nway_lp_ability_reg & NWAY_LPAR_ASM_DIR)) {
 584                        hw->fc.current_mode = igc_fc_rx_pause;
 585                        hw_dbg("Flow Control = RX PAUSE frames only.\n");
 586                }
 587                /* Per the IEEE spec, at this point flow control should be
 588                 * disabled.  However, we want to consider that we could
 589                 * be connected to a legacy switch that doesn't advertise
 590                 * desired flow control, but can be forced on the link
 591                 * partner.  So if we advertised no flow control, that is
 592                 * what we will resolve to.  If we advertised some kind of
 593                 * receive capability (Rx Pause Only or Full Flow Control)
 594                 * and the link partner advertised none, we will configure
 595                 * ourselves to enable Rx Flow Control only.  We can do
 596                 * this safely for two reasons:  If the link partner really
 597                 * didn't want flow control enabled, and we enable Rx, no
 598                 * harm done since we won't be receiving any PAUSE frames
 599                 * anyway.  If the intent on the link partner was to have
 600                 * flow control enabled, then by us enabling RX only, we
 601                 * can at least receive pause frames and process them.
 602                 * This is a good idea because in most cases, since we are
 603                 * predominantly a server NIC, more times than not we will
 604                 * be asked to delay transmission of packets than asking
 605                 * our link partner to pause transmission of frames.
 606                 */
 607                else if ((hw->fc.requested_mode == igc_fc_none) ||
 608                         (hw->fc.requested_mode == igc_fc_tx_pause) ||
 609                         (hw->fc.strict_ieee)) {
 610                        hw->fc.current_mode = igc_fc_none;
 611                        hw_dbg("Flow Control = NONE.\n");
 612                } else {
 613                        hw->fc.current_mode = igc_fc_rx_pause;
 614                        hw_dbg("Flow Control = RX PAUSE frames only.\n");
 615                }
 616
 617                /* Now we need to do one last check...  If we auto-
 618                 * negotiated to HALF DUPLEX, flow control should not be
 619                 * enabled per IEEE 802.3 spec.
 620                 */
 621                ret_val = hw->mac.ops.get_speed_and_duplex(hw, &speed, &duplex);
 622                if (ret_val) {
 623                        hw_dbg("Error getting link speed and duplex\n");
 624                        goto out;
 625                }
 626
 627                if (duplex == HALF_DUPLEX)
 628                        hw->fc.current_mode = igc_fc_none;
 629
 630                /* Now we call a subroutine to actually force the MAC
 631                 * controller to use the correct flow control settings.
 632                 */
 633                ret_val = igc_force_mac_fc(hw);
 634                if (ret_val) {
 635                        hw_dbg("Error forcing flow control settings\n");
 636                        goto out;
 637                }
 638        }
 639
 640out:
 641        return ret_val;
 642}
 643
 644/**
 645 * igc_get_auto_rd_done - Check for auto read completion
 646 * @hw: pointer to the HW structure
 647 *
 648 * Check EEPROM for Auto Read done bit.
 649 */
 650s32 igc_get_auto_rd_done(struct igc_hw *hw)
 651{
 652        s32 ret_val = 0;
 653        s32 i = 0;
 654
 655        while (i < AUTO_READ_DONE_TIMEOUT) {
 656                if (rd32(IGC_EECD) & IGC_EECD_AUTO_RD)
 657                        break;
 658                usleep_range(1000, 2000);
 659                i++;
 660        }
 661
 662        if (i == AUTO_READ_DONE_TIMEOUT) {
 663                hw_dbg("Auto read by HW from NVM has not completed.\n");
 664                ret_val = -IGC_ERR_RESET;
 665                goto out;
 666        }
 667
 668out:
 669        return ret_val;
 670}
 671
 672/**
 673 * igc_get_speed_and_duplex_copper - Retrieve current speed/duplex
 674 * @hw: pointer to the HW structure
 675 * @speed: stores the current speed
 676 * @duplex: stores the current duplex
 677 *
 678 * Read the status register for the current speed/duplex and store the current
 679 * speed and duplex for copper connections.
 680 */
 681s32 igc_get_speed_and_duplex_copper(struct igc_hw *hw, u16 *speed,
 682                                    u16 *duplex)
 683{
 684        u32 status;
 685
 686        status = rd32(IGC_STATUS);
 687        if (status & IGC_STATUS_SPEED_1000) {
 688                /* For I225, STATUS will indicate 1G speed in both 1 Gbps
 689                 * and 2.5 Gbps link modes. An additional bit is used
 690                 * to differentiate between 1 Gbps and 2.5 Gbps.
 691                 */
 692                if (hw->mac.type == igc_i225 &&
 693                    (status & IGC_STATUS_SPEED_2500)) {
 694                        *speed = SPEED_2500;
 695                        hw_dbg("2500 Mbs, ");
 696                } else {
 697                        *speed = SPEED_1000;
 698                        hw_dbg("1000 Mbs, ");
 699                }
 700        } else if (status & IGC_STATUS_SPEED_100) {
 701                *speed = SPEED_100;
 702                hw_dbg("100 Mbs, ");
 703        } else {
 704                *speed = SPEED_10;
 705                hw_dbg("10 Mbs, ");
 706        }
 707
 708        if (status & IGC_STATUS_FD) {
 709                *duplex = FULL_DUPLEX;
 710                hw_dbg("Full Duplex\n");
 711        } else {
 712                *duplex = HALF_DUPLEX;
 713                hw_dbg("Half Duplex\n");
 714        }
 715
 716        return 0;
 717}
 718
 719/**
 720 * igc_put_hw_semaphore - Release hardware semaphore
 721 * @hw: pointer to the HW structure
 722 *
 723 * Release hardware semaphore used to access the PHY or NVM
 724 */
 725void igc_put_hw_semaphore(struct igc_hw *hw)
 726{
 727        u32 swsm;
 728
 729        swsm = rd32(IGC_SWSM);
 730
 731        swsm &= ~(IGC_SWSM_SMBI | IGC_SWSM_SWESMBI);
 732
 733        wr32(IGC_SWSM, swsm);
 734}
 735
 736/**
 737 * igc_enable_mng_pass_thru - Enable processing of ARP's
 738 * @hw: pointer to the HW structure
 739 *
 740 * Verifies the hardware needs to leave interface enabled so that frames can
 741 * be directed to and from the management interface.
 742 */
 743bool igc_enable_mng_pass_thru(struct igc_hw *hw)
 744{
 745        bool ret_val = false;
 746        u32 fwsm, factps;
 747        u32 manc;
 748
 749        if (!hw->mac.asf_firmware_present)
 750                goto out;
 751
 752        manc = rd32(IGC_MANC);
 753
 754        if (!(manc & IGC_MANC_RCV_TCO_EN))
 755                goto out;
 756
 757        if (hw->mac.arc_subsystem_valid) {
 758                fwsm = rd32(IGC_FWSM);
 759                factps = rd32(IGC_FACTPS);
 760
 761                if (!(factps & IGC_FACTPS_MNGCG) &&
 762                    ((fwsm & IGC_FWSM_MODE_MASK) ==
 763                    (igc_mng_mode_pt << IGC_FWSM_MODE_SHIFT))) {
 764                        ret_val = true;
 765                        goto out;
 766                }
 767        } else {
 768                if ((manc & IGC_MANC_SMBUS_EN) &&
 769                    !(manc & IGC_MANC_ASF_EN)) {
 770                        ret_val = true;
 771                        goto out;
 772                }
 773        }
 774
 775out:
 776        return ret_val;
 777}
 778
 779/**
 780 *  igc_hash_mc_addr - Generate a multicast hash value
 781 *  @hw: pointer to the HW structure
 782 *  @mc_addr: pointer to a multicast address
 783 *
 784 *  Generates a multicast address hash value which is used to determine
 785 *  the multicast filter table array address and new table value.  See
 786 *  igc_mta_set()
 787 **/
 788static u32 igc_hash_mc_addr(struct igc_hw *hw, u8 *mc_addr)
 789{
 790        u32 hash_value, hash_mask;
 791        u8 bit_shift = 0;
 792
 793        /* Register count multiplied by bits per register */
 794        hash_mask = (hw->mac.mta_reg_count * 32) - 1;
 795
 796        /* For a mc_filter_type of 0, bit_shift is the number of left-shifts
 797         * where 0xFF would still fall within the hash mask.
 798         */
 799        while (hash_mask >> bit_shift != 0xFF)
 800                bit_shift++;
 801
 802        /* The portion of the address that is used for the hash table
 803         * is determined by the mc_filter_type setting.
 804         * The algorithm is such that there is a total of 8 bits of shifting.
 805         * The bit_shift for a mc_filter_type of 0 represents the number of
 806         * left-shifts where the MSB of mc_addr[5] would still fall within
 807         * the hash_mask.  Case 0 does this exactly.  Since there are a total
 808         * of 8 bits of shifting, then mc_addr[4] will shift right the
 809         * remaining number of bits. Thus 8 - bit_shift.  The rest of the
 810         * cases are a variation of this algorithm...essentially raising the
 811         * number of bits to shift mc_addr[5] left, while still keeping the
 812         * 8-bit shifting total.
 813         *
 814         * For example, given the following Destination MAC Address and an
 815         * MTA register count of 128 (thus a 4096-bit vector and 0xFFF mask),
 816         * we can see that the bit_shift for case 0 is 4.  These are the hash
 817         * values resulting from each mc_filter_type...
 818         * [0] [1] [2] [3] [4] [5]
 819         * 01  AA  00  12  34  56
 820         * LSB                 MSB
 821         *
 822         * case 0: hash_value = ((0x34 >> 4) | (0x56 << 4)) & 0xFFF = 0x563
 823         * case 1: hash_value = ((0x34 >> 3) | (0x56 << 5)) & 0xFFF = 0xAC6
 824         * case 2: hash_value = ((0x34 >> 2) | (0x56 << 6)) & 0xFFF = 0x163
 825         * case 3: hash_value = ((0x34 >> 0) | (0x56 << 8)) & 0xFFF = 0x634
 826         */
 827        switch (hw->mac.mc_filter_type) {
 828        default:
 829        case 0:
 830                break;
 831        case 1:
 832                bit_shift += 1;
 833                break;
 834        case 2:
 835                bit_shift += 2;
 836                break;
 837        case 3:
 838                bit_shift += 4;
 839                break;
 840        }
 841
 842        hash_value = hash_mask & (((mc_addr[4] >> (8 - bit_shift)) |
 843                                  (((u16)mc_addr[5]) << bit_shift)));
 844
 845        return hash_value;
 846}
 847
 848/**
 849 *  igc_update_mc_addr_list - Update Multicast addresses
 850 *  @hw: pointer to the HW structure
 851 *  @mc_addr_list: array of multicast addresses to program
 852 *  @mc_addr_count: number of multicast addresses to program
 853 *
 854 *  Updates entire Multicast Table Array.
 855 *  The caller must have a packed mc_addr_list of multicast addresses.
 856 **/
 857void igc_update_mc_addr_list(struct igc_hw *hw,
 858                             u8 *mc_addr_list, u32 mc_addr_count)
 859{
 860        u32 hash_value, hash_bit, hash_reg;
 861        int i;
 862
 863        /* clear mta_shadow */
 864        memset(&hw->mac.mta_shadow, 0, sizeof(hw->mac.mta_shadow));
 865
 866        /* update mta_shadow from mc_addr_list */
 867        for (i = 0; (u32)i < mc_addr_count; i++) {
 868                hash_value = igc_hash_mc_addr(hw, mc_addr_list);
 869
 870                hash_reg = (hash_value >> 5) & (hw->mac.mta_reg_count - 1);
 871                hash_bit = hash_value & 0x1F;
 872
 873                hw->mac.mta_shadow[hash_reg] |= BIT(hash_bit);
 874                mc_addr_list += ETH_ALEN;
 875        }
 876
 877        /* replace the entire MTA table */
 878        for (i = hw->mac.mta_reg_count - 1; i >= 0; i--)
 879                array_wr32(IGC_MTA, i, hw->mac.mta_shadow[i]);
 880        wrfl();
 881}
 882