drivers/net/mdio.c

   1 /*
   2  * mdio.c: Generic support for MDIO-compatible transceivers
   3  * Copyright 2006-2009 Solarflare Communications Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published
   7  * by the Free Software Foundation, incorporated herein by reference.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/capability.h>
  12 #include <linux/errno.h>
  13 #include <linux/ethtool.h>
  14 #include <linux/mdio.h>
  15 #include <linux/module.h>
  16
  17 /**
  18  * mdio45_probe - probe for an MDIO (clause 45) device
  19  * @mdio: MDIO interface
  20  * @prtad: Expected PHY address
  21  *
  22  * This sets @prtad and @mmds in the MDIO interface if successful.
  23  * Returns 0 on success, negative on error.
  24  */
  25 int mdio45_probe(struct mdio_if_info *mdio, int prtad)
  26 {
  27         int mmd, stat2, devs1, devs2;
  28
  29         /* Assume PHY must have at least one of PMA/PMD, WIS, PCS, PHY
  30          * XS or DTE XS; give up if none is present. */
  31         for (mmd = 1; mmd <= 5; mmd++) {
  32                 /* Is this MMD present? */
  33                 stat2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_STAT2);
  34                 if (stat2 < 0 ||
  35                     (stat2 & MDIO_STAT2_DEVPRST) != MDIO_STAT2_DEVPRST_VAL)
  36                         continue;
  37
  38                 /* It should tell us about all the other MMDs */
  39                 devs1 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS1);
  40                 devs2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS2);
  41                 if (devs1 < 0 || devs2 < 0)
  42                         continue;
  43
  44                 mdio->prtad = prtad;
  45                 mdio->mmds = devs1 | (devs2 << 16);
  46                 return 0;
  47         }
  48
  49         return -ENODEV;
  50 }
  51 EXPORT_SYMBOL(mdio45_probe);
  52
  53 /**
  54  * mdio_set_flag - set or clear flag in an MDIO register
  55  * @mdio: MDIO interface
  56  * @prtad: PHY address
  57  * @devad: MMD address
  58  * @addr: Register address
  59  * @mask: Mask for flag (single bit set)
  60  * @sense: New value of flag
  61  *
  62  * This debounces changes: it does not write the register if the flag
  63  * already has the proper value.  Returns 0 on success, negative on error.
  64  */
  65 int mdio_set_flag(const struct mdio_if_info *mdio,
  66                   int prtad, int devad, u16 addr, int mask,
  67                   bool sense)
  68 {
  69         int old_val = mdio->mdio_read(mdio->dev, prtad, devad, addr);
  70         int new_val;
  71
  72         if (old_val < 0)
  73                 return old_val;
  74         if (sense)
  75                 new_val = old_val | mask;
  76         else
  77                 new_val = old_val & ~mask;
  78         if (old_val == new_val)
  79                 return 0;
  80         return mdio->mdio_write(mdio->dev, prtad, devad, addr, new_val);
  81 }
  82 EXPORT_SYMBOL(mdio_set_flag);
  83
  84 /**
  85  * mdio_link_ok - is link status up/OK
  86  * @mdio: MDIO interface
  87  * @mmd_mask: Mask for MMDs to check
  88  *
  89  * Returns 1 if the PHY reports link status up/OK, 0 otherwise.
  90  * @mmd_mask is normally @mdio->mmds, but if loopback is enabled
  91  * the MMDs being bypassed should be excluded from the mask.
  92  */
  93 int mdio45_links_ok(const struct mdio_if_info *mdio, u32 mmd_mask)
  94 {
  95         int devad, reg;
  96
  97         if (!mmd_mask) {
  98                 /* Use absence of XGMII faults in lieu of link state */
  99                 reg = mdio->mdio_read(mdio->dev, mdio->prtad,
 100                                       MDIO_MMD_PHYXS, MDIO_STAT2);
 101                 return reg >= 0 && !(reg & MDIO_STAT2_RXFAULT);
 102         }
 103
 104         for (devad = 0; mmd_mask; devad++) {
 105                 if (mmd_mask & (1 << devad)) {
 106                         mmd_mask &= ~(1 << devad);
 107
 108                         /* Read twice because link state is latched and a
 109                          * read moves the current state into the register */
 110                         mdio->mdio_read(mdio->dev, mdio->prtad,
 111                                         devad, MDIO_STAT1);
 112                         reg = mdio->mdio_read(mdio->dev, mdio->prtad,
 113                                               devad, MDIO_STAT1);
 114                         if (reg < 0 || !(reg & MDIO_STAT1_LSTATUS))
 115                                 return false;
 116                 }
 117         }
 118
 119         return true;
 120 }
 121 EXPORT_SYMBOL(mdio45_links_ok);
 122
 123 /**
 124  * mdio45_nway_restart - restart auto-negotiation for this interface
 125  * @mdio: MDIO interface
 126  *
 127  * Returns 0 on success, negative on error.
 128  */
 129 int mdio45_nway_restart(const struct mdio_if_info *mdio)
 130 {
 131         if (!(mdio->mmds & MDIO_DEVS_AN))
 132                 return -EOPNOTSUPP;
 133
 134         mdio_set_flag(mdio, mdio->prtad, MDIO_MMD_AN, MDIO_CTRL1,
 135                       MDIO_AN_CTRL1_RESTART, true);
 136         return 0;
 137 }
 138 EXPORT_SYMBOL(mdio45_nway_restart);
 139
 140 static u32 mdio45_get_an(const struct mdio_if_info *mdio, u16 addr)
 141 {
 142         u32 result = 0;
 143         int reg;
 144
 145         reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN, addr);
 146         if (reg & ADVERTISE_10HALF)
 147                 result |= ADVERTISED_10baseT_Half;
 148         if (reg & ADVERTISE_10FULL)
 149                 result |= ADVERTISED_10baseT_Full;
 150         if (reg & ADVERTISE_100HALF)
 151                 result |= ADVERTISED_100baseT_Half;
 152         if (reg & ADVERTISE_100FULL)
 153                 result |= ADVERTISED_100baseT_Full;
 154         return result;
 155 }
 156
 157 /**
 158  * mdio45_ethtool_gset_npage - get settings for ETHTOOL_GSET
 159  * @mdio: MDIO interface
 160  * @ecmd: Ethtool request structure
 161  * @npage_adv: Modes currently advertised on next pages
 162  * @npage_lpa: Modes advertised by link partner on next pages
 163  *
 164  * Since the CSRs for auto-negotiation using next pages are not fully
 165  * standardised, this function does not attempt to decode them.  The
 166  * caller must pass them in.
 167  */
 168 void mdio45_ethtool_gset_npage(const struct mdio_if_info *mdio,
 169                                struct ethtool_cmd *ecmd,
 170                                u32 npage_adv, u32 npage_lpa)
 171 {
 172         int reg;
 173
 174         ecmd->transceiver = XCVR_INTERNAL;
 175         ecmd->phy_address = mdio->prtad;
 176         ecmd->mdio_support =
 177                 mdio->mode_support & (MDIO_SUPPORTS_C45 | MDIO_SUPPORTS_C22);
 178
 179         reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 180                               MDIO_CTRL2);
 181         switch (reg & MDIO_PMA_CTRL2_TYPE) {
 182         case MDIO_PMA_CTRL2_10GBT:
 183         case MDIO_PMA_CTRL2_1000BT:
 184         case MDIO_PMA_CTRL2_100BTX:
 185         case MDIO_PMA_CTRL2_10BT:
 186                 ecmd->port = PORT_TP;
 187                 ecmd->supported = SUPPORTED_TP;
 188                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 189                                       MDIO_SPEED);
 190                 if (reg & MDIO_SPEED_10G)
 191                         ecmd->supported |= SUPPORTED_10000baseT_Full;
 192                 if (reg & MDIO_PMA_SPEED_1000)
 193                         ecmd->supported |= (SUPPORTED_1000baseT_Full |
 194                                             SUPPORTED_1000baseT_Half);
 195                 if (reg & MDIO_PMA_SPEED_100)
 196                         ecmd->supported |= (SUPPORTED_100baseT_Full |
 197                                             SUPPORTED_100baseT_Half);
 198                 if (reg & MDIO_PMA_SPEED_10)
 199                         ecmd->supported |= (SUPPORTED_10baseT_Full |
 200                                             SUPPORTED_10baseT_Half);
 201                 ecmd->advertising = ADVERTISED_TP;
 202                 break;
 203
 204         case MDIO_PMA_CTRL2_10GBCX4:
 205                 ecmd->port = PORT_OTHER;
 206                 ecmd->supported = 0;
 207                 ecmd->advertising = 0;
 208                 break;
 209
 210         case MDIO_PMA_CTRL2_10GBKX4:
 211         case MDIO_PMA_CTRL2_10GBKR:
 212         case MDIO_PMA_CTRL2_1000BKX:
 213                 ecmd->port = PORT_OTHER;
 214                 ecmd->supported = SUPPORTED_Backplane;
 215                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 216                                       MDIO_PMA_EXTABLE);
 217                 if (reg & MDIO_PMA_EXTABLE_10GBKX4)
 218                         ecmd->supported |= SUPPORTED_10000baseKX4_Full;
 219                 if (reg & MDIO_PMA_EXTABLE_10GBKR)
 220                         ecmd->supported |= SUPPORTED_10000baseKR_Full;
 221                 if (reg & MDIO_PMA_EXTABLE_1000BKX)
 222                         ecmd->supported |= SUPPORTED_1000baseKX_Full;
 223                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 224                                       MDIO_PMA_10GBR_FECABLE);
 225                 if (reg & MDIO_PMA_10GBR_FECABLE_ABLE)
 226                         ecmd->supported |= SUPPORTED_10000baseR_FEC;
 227                 ecmd->advertising = ADVERTISED_Backplane;
 228                 break;
 229
 230         /* All the other defined modes are flavours of optical */
 231         default:
 232                 ecmd->port = PORT_FIBRE;
 233                 ecmd->supported = SUPPORTED_FIBRE;
 234                 ecmd->advertising = ADVERTISED_FIBRE;
 235                 break;
 236         }
 237
 238         if (mdio->mmds & MDIO_DEVS_AN) {
 239                 ecmd->supported |= SUPPORTED_Autoneg;
 240                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 241                                       MDIO_CTRL1);
 242                 if (reg & MDIO_AN_CTRL1_ENABLE) {
 243                         ecmd->autoneg = AUTONEG_ENABLE;
 244                         ecmd->advertising |=
 245                                 ADVERTISED_Autoneg |
 246                                 mdio45_get_an(mdio, MDIO_AN_ADVERTISE) |
 247                                 npage_adv;
 248                 } else {
 249                         ecmd->autoneg = AUTONEG_DISABLE;
 250                 }
 251         } else {
 252                 ecmd->autoneg = AUTONEG_DISABLE;
 253         }
 254
 255         if (ecmd->autoneg) {
 256                 u32 modes = 0;
 257                 int an_stat = mdio->mdio_read(mdio->dev, mdio->prtad,
 258                                               MDIO_MMD_AN, MDIO_STAT1);
 259
 260                 /* If AN is complete and successful, report best common
 261                  * mode, otherwise report best advertised mode. */
 262                 if (an_stat & MDIO_AN_STAT1_COMPLETE) {
 263                         ecmd->lp_advertising =
 264                                 mdio45_get_an(mdio, MDIO_AN_LPA) | npage_lpa;
 265                         if (an_stat & MDIO_AN_STAT1_LPABLE)
 266                                 ecmd->lp_advertising |= ADVERTISED_Autoneg;
 267                         modes = ecmd->advertising & ecmd->lp_advertising;
 268                 }
 269                 if ((modes & ~ADVERTISED_Autoneg) == 0)
 270                         modes = ecmd->advertising;
 271
 272                 if (modes & (ADVERTISED_10000baseT_Full |
 273                              ADVERTISED_10000baseKX4_Full |
 274                              ADVERTISED_10000baseKR_Full)) {
 275                         ecmd->speed = SPEED_10000;
 276                         ecmd->duplex = DUPLEX_FULL;
 277                 } else if (modes & (ADVERTISED_1000baseT_Full |
 278                                     ADVERTISED_1000baseT_Half |
 279                                     ADVERTISED_1000baseKX_Full)) {
 280                         ecmd->speed = SPEED_1000;
 281                         ecmd->duplex = !(modes & ADVERTISED_1000baseT_Half);
 282                 } else if (modes & (ADVERTISED_100baseT_Full |
 283                                     ADVERTISED_100baseT_Half)) {
 284                         ecmd->speed = SPEED_100;
 285                         ecmd->duplex = !!(modes & ADVERTISED_100baseT_Full);
 286                 } else {
 287                         ecmd->speed = SPEED_10;
 288                         ecmd->duplex = !!(modes & ADVERTISED_10baseT_Full);
 289                 }
 290         } else {
 291                 /* Report forced settings */
 292                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 293                                       MDIO_CTRL1);
 294                 ecmd->speed = (((reg & MDIO_PMA_CTRL1_SPEED1000) ? 100 : 1) *
 295                                ((reg & MDIO_PMA_CTRL1_SPEED100) ? 100 : 10));
 296                 ecmd->duplex = (reg & MDIO_CTRL1_FULLDPLX ||
 297                                 ecmd->speed == SPEED_10000);
 298         }
 299
 300         /* 10GBASE-T MDI/MDI-X */
 301         if (ecmd->port == PORT_TP && ecmd->speed == SPEED_10000) {
 302                 switch (mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 303                                         MDIO_PMA_10GBT_SWAPPOL)) {
 304                 case MDIO_PMA_10GBT_SWAPPOL_ABNX | MDIO_PMA_10GBT_SWAPPOL_CDNX:
 305                         ecmd->eth_tp_mdix = ETH_TP_MDI;
 306                         break;
 307                 case 0:
 308                         ecmd->eth_tp_mdix = ETH_TP_MDI_X;
 309                         break;
 310                 default:
 311                         /* It's complicated... */
 312                         ecmd->eth_tp_mdix = ETH_TP_MDI_INVALID;
 313                         break;
 314                 }
 315         }
 316 }
 317 EXPORT_SYMBOL(mdio45_ethtool_gset_npage);
 318
 319 /**
 320  * mdio45_ethtool_spauseparam_an - set auto-negotiated pause parameters
 321  * @mdio: MDIO interface
 322  * @ecmd: Ethtool request structure
 323  *
 324  * This function assumes that the PHY has an auto-negotiation MMD.  It
 325  * will enable and disable advertising of flow control as appropriate.
 326  */
 327 void mdio45_ethtool_spauseparam_an(const struct mdio_if_info *mdio,
 328                                    const struct ethtool_pauseparam *ecmd)
 329 {
 330         int adv, old_adv;
 331
 332         WARN_ON(!(mdio->mmds & MDIO_DEVS_AN));
 333
 334         old_adv = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 335                                   MDIO_AN_ADVERTISE);
 336         adv = old_adv & ~(ADVERTISE_PAUSE_CAP | ADVERTISE_PAUSE_ASYM);
 337         if (ecmd->autoneg)
 338                 adv |= mii_advertise_flowctrl(
 339                         (ecmd->rx_pause ? FLOW_CTRL_RX : 0) |
 340                         (ecmd->tx_pause ? FLOW_CTRL_TX : 0));
 341         if (adv != old_adv) {
 342                 mdio->mdio_write(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 343                                  MDIO_AN_ADVERTISE, adv);
 344                 mdio45_nway_restart(mdio);
 345         }
 346 }
 347 EXPORT_SYMBOL(mdio45_ethtool_spauseparam_an);
 348
 349 /**
 350  * mdio_mii_ioctl - MII ioctl interface for MDIO (clause 22 or 45) PHYs
 351  * @mdio: MDIO interface
 352  * @mii_data: MII ioctl data structure
 353  * @cmd: MII ioctl command
 354  *
 355  * Returns 0 on success, negative on error.
 356  */
 357 int mdio_mii_ioctl(const struct mdio_if_info *mdio,
 358                    struct mii_ioctl_data *mii_data, int cmd)
 359 {
 360         int prtad, devad;
 361         u16 addr = mii_data->reg_num;
 362
 363         /* Validate/convert cmd to one of SIOC{G,S}MIIREG */
 364         switch (cmd) {
 365         case SIOCGMIIPHY:
 366                 if (mdio->prtad == MDIO_PRTAD_NONE)
 367                         return -EOPNOTSUPP;
 368                 mii_data->phy_id = mdio->prtad;
 369                 cmd = SIOCGMIIREG;
 370                 break;
 371         case SIOCGMIIREG:
 372                 break;
 373         case SIOCSMIIREG:
 374                 if (!capable(CAP_NET_ADMIN))
 375                         return -EPERM;
 376                 break;
 377         default:
 378                 return -EOPNOTSUPP;
 379         }
 380
 381         /* Validate/convert phy_id */
 382         if ((mdio->mode_support & MDIO_SUPPORTS_C45) &&
 383             mdio_phy_id_is_c45(mii_data->phy_id)) {
 384                 prtad = mdio_phy_id_prtad(mii_data->phy_id);
 385                 devad = mdio_phy_id_devad(mii_data->phy_id);
 386         } else if ((mdio->mode_support & MDIO_SUPPORTS_C22) &&
 387                    mii_data->phy_id < 0x20) {
 388                 prtad = mii_data->phy_id;
 389                 devad = MDIO_DEVAD_NONE;
 390                 addr &= 0x1f;
 391         } else if ((mdio->mode_support & MDIO_EMULATE_C22) &&
 392                    mdio->prtad != MDIO_PRTAD_NONE &&
 393                    mii_data->phy_id == mdio->prtad) {
 394                 /* Remap commonly-used MII registers. */
 395                 prtad = mdio->prtad;
 396                 switch (addr) {
 397                 case MII_BMCR:
 398                 case MII_BMSR:
 399                 case MII_PHYSID1:
 400                 case MII_PHYSID2:
 401                         devad = __ffs(mdio->mmds);
 402                         break;
 403                 case MII_ADVERTISE:
 404                 case MII_LPA:
 405                         if (!(mdio->mmds & MDIO_DEVS_AN))
 406                                 return -EINVAL;
 407                         devad = MDIO_MMD_AN;
 408                         if (addr == MII_ADVERTISE)
 409                                 addr = MDIO_AN_ADVERTISE;
 410                         else
 411                                 addr = MDIO_AN_LPA;
 412                         break;
 413                 default:
 414                         return -EINVAL;
 415                 }
 416         } else {
 417                 return -EINVAL;
 418         }
 419
 420         if (cmd == SIOCGMIIREG) {
 421                 int rc = mdio->mdio_read(mdio->dev, prtad, devad, addr);
 422                 if (rc < 0)
 423                         return rc;
 424                 mii_data->val_out = rc;
 425                 return 0;
 426         } else {
 427                 return mdio->mdio_write(mdio->dev, prtad, devad, addr,
 428                                         mii_data->val_in);
 429         }
 430 }
 431 EXPORT_SYMBOL(mdio_mii_ioctl);