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 MODULE_DESCRIPTION("Generic support for MDIO-compatible transceivers");
  18 MODULE_AUTHOR("Copyright 2006-2009 Solarflare Communications Inc.");
  19 MODULE_LICENSE("GPL");
  20
  21 /**
  22  * mdio45_probe - probe for an MDIO (clause 45) device
  23  * @mdio: MDIO interface
  24  * @prtad: Expected PHY address
  25  *
  26  * This sets @prtad and @mmds in the MDIO interface if successful.
  27  * Returns 0 on success, negative on error.
  28  */
  29 int mdio45_probe(struct mdio_if_info *mdio, int prtad)
  30 {
  31         int mmd, stat2, devs1, devs2;
  32
  33         /* Assume PHY must have at least one of PMA/PMD, WIS, PCS, PHY
  34          * XS or DTE XS; give up if none is present. */
  35         for (mmd = 1; mmd <= 5; mmd++) {
  36                 /* Is this MMD present? */
  37                 stat2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_STAT2);
  38                 if (stat2 < 0 ||
  39                     (stat2 & MDIO_STAT2_DEVPRST) != MDIO_STAT2_DEVPRST_VAL)
  40                         continue;
  41
  42                 /* It should tell us about all the other MMDs */
  43                 devs1 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS1);
  44                 devs2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS2);
  45                 if (devs1 < 0 || devs2 < 0)
  46                         continue;
  47
  48                 mdio->prtad = prtad;
  49                 mdio->mmds = devs1 | (devs2 << 16);
  50                 return 0;
  51         }
  52
  53         return -ENODEV;
  54 }
  55 EXPORT_SYMBOL(mdio45_probe);
  56
  57 /**
  58  * mdio_set_flag - set or clear flag in an MDIO register
  59  * @mdio: MDIO interface
  60  * @prtad: PHY address
  61  * @devad: MMD address
  62  * @addr: Register address
  63  * @mask: Mask for flag (single bit set)
  64  * @sense: New value of flag
  65  *
  66  * This debounces changes: it does not write the register if the flag
  67  * already has the proper value.  Returns 0 on success, negative on error.
  68  */
  69 int mdio_set_flag(const struct mdio_if_info *mdio,
  70                   int prtad, int devad, u16 addr, int mask,
  71                   bool sense)
  72 {
  73         int old_val = mdio->mdio_read(mdio->dev, prtad, devad, addr);
  74         int new_val;
  75
  76         if (old_val < 0)
  77                 return old_val;
  78         if (sense)
  79                 new_val = old_val | mask;
  80         else
  81                 new_val = old_val & ~mask;
  82         if (old_val == new_val)
  83                 return 0;
  84         return mdio->mdio_write(mdio->dev, prtad, devad, addr, new_val);
  85 }
  86 EXPORT_SYMBOL(mdio_set_flag);
  87
  88 /**
  89  * mdio_link_ok - is link status up/OK
  90  * @mdio: MDIO interface
  91  * @mmd_mask: Mask for MMDs to check
  92  *
  93  * Returns 1 if the PHY reports link status up/OK, 0 otherwise.
  94  * @mmd_mask is normally @mdio->mmds, but if loopback is enabled
  95  * the MMDs being bypassed should be excluded from the mask.
  96  */
  97 int mdio45_links_ok(const struct mdio_if_info *mdio, u32 mmd_mask)
  98 {
  99         int devad, reg;
 100
 101         if (!mmd_mask) {
 102                 /* Use absence of XGMII faults in lieu of link state */
 103                 reg = mdio->mdio_read(mdio->dev, mdio->prtad,
 104                                       MDIO_MMD_PHYXS, MDIO_STAT2);
 105                 return reg >= 0 && !(reg & MDIO_STAT2_RXFAULT);
 106         }
 107
 108         for (devad = 0; mmd_mask; devad++) {
 109                 if (mmd_mask & (1 << devad)) {
 110                         mmd_mask &= ~(1 << devad);
 111
 112                         /* Read twice because link state is latched and a
 113                          * read moves the current state into the register */
 114                         mdio->mdio_read(mdio->dev, mdio->prtad,
 115                                         devad, MDIO_STAT1);
 116                         reg = mdio->mdio_read(mdio->dev, mdio->prtad,
 117                                               devad, MDIO_STAT1);
 118                         if (reg < 0 || !(reg & MDIO_STAT1_LSTATUS))
 119                                 return false;
 120                 }
 121         }
 122
 123         return true;
 124 }
 125 EXPORT_SYMBOL(mdio45_links_ok);
 126
 127 /**
 128  * mdio45_nway_restart - restart auto-negotiation for this interface
 129  * @mdio: MDIO interface
 130  *
 131  * Returns 0 on success, negative on error.
 132  */
 133 int mdio45_nway_restart(const struct mdio_if_info *mdio)
 134 {
 135         if (!(mdio->mmds & MDIO_DEVS_AN))
 136                 return -EOPNOTSUPP;
 137
 138         mdio_set_flag(mdio, mdio->prtad, MDIO_MMD_AN, MDIO_CTRL1,
 139                       MDIO_AN_CTRL1_RESTART, true);
 140         return 0;
 141 }
 142 EXPORT_SYMBOL(mdio45_nway_restart);
 143
 144 static u32 mdio45_get_an(const struct mdio_if_info *mdio, u16 addr)
 145 {
 146         u32 result = 0;
 147         int reg;
 148
 149         reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN, addr);
 150         if (reg & ADVERTISE_10HALF)
 151                 result |= ADVERTISED_10baseT_Half;
 152         if (reg & ADVERTISE_10FULL)
 153                 result |= ADVERTISED_10baseT_Full;
 154         if (reg & ADVERTISE_100HALF)
 155                 result |= ADVERTISED_100baseT_Half;
 156         if (reg & ADVERTISE_100FULL)
 157                 result |= ADVERTISED_100baseT_Full;
 158         return result;
 159 }
 160
 161 /**
 162  * mdio45_ethtool_gset_npage - get settings for ETHTOOL_GSET
 163  * @mdio: MDIO interface
 164  * @ecmd: Ethtool request structure
 165  * @npage_adv: Modes currently advertised on next pages
 166  * @npage_lpa: Modes advertised by link partner on next pages
 167  *
 168  * Since the CSRs for auto-negotiation using next pages are not fully
 169  * standardised, this function does not attempt to decode them.  The
 170  * caller must pass them in.
 171  */
 172 void mdio45_ethtool_gset_npage(const struct mdio_if_info *mdio,
 173                                struct ethtool_cmd *ecmd,
 174                                u32 npage_adv, u32 npage_lpa)
 175 {
 176         int reg;
 177
 178         ecmd->transceiver = XCVR_INTERNAL;
 179         ecmd->phy_address = mdio->prtad;
 180         ecmd->mdio_support =
 181                 mdio->mode_support & (MDIO_SUPPORTS_C45 | MDIO_SUPPORTS_C22);
 182
 183         reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 184                               MDIO_CTRL2);
 185         switch (reg & MDIO_PMA_CTRL2_TYPE) {
 186         case MDIO_PMA_CTRL2_10GBT:
 187         case MDIO_PMA_CTRL2_1000BT:
 188         case MDIO_PMA_CTRL2_100BTX:
 189         case MDIO_PMA_CTRL2_10BT:
 190                 ecmd->port = PORT_TP;
 191                 ecmd->supported = SUPPORTED_TP;
 192                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 193                                       MDIO_SPEED);
 194                 if (reg & MDIO_SPEED_10G)
 195                         ecmd->supported |= SUPPORTED_10000baseT_Full;
 196                 if (reg & MDIO_PMA_SPEED_1000)
 197                         ecmd->supported |= (SUPPORTED_1000baseT_Full |
 198                                             SUPPORTED_1000baseT_Half);
 199                 if (reg & MDIO_PMA_SPEED_100)
 200                         ecmd->supported |= (SUPPORTED_100baseT_Full |
 201                                             SUPPORTED_100baseT_Half);
 202                 if (reg & MDIO_PMA_SPEED_10)
 203                         ecmd->supported |= (SUPPORTED_10baseT_Full |
 204                                             SUPPORTED_10baseT_Half);
 205                 ecmd->advertising = ADVERTISED_TP;
 206                 break;
 207
 208         case MDIO_PMA_CTRL2_10GBCX4:
 209                 ecmd->port = PORT_OTHER;
 210                 ecmd->supported = 0;
 211                 ecmd->advertising = 0;
 212                 break;
 213
 214         case MDIO_PMA_CTRL2_10GBKX4:
 215         case MDIO_PMA_CTRL2_10GBKR:
 216         case MDIO_PMA_CTRL2_1000BKX:
 217                 ecmd->port = PORT_OTHER;
 218                 ecmd->supported = SUPPORTED_Backplane;
 219                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 220                                       MDIO_PMA_EXTABLE);
 221                 if (reg & MDIO_PMA_EXTABLE_10GBKX4)
 222                         ecmd->supported |= SUPPORTED_10000baseKX4_Full;
 223                 if (reg & MDIO_PMA_EXTABLE_10GBKR)
 224                         ecmd->supported |= SUPPORTED_10000baseKR_Full;
 225                 if (reg & MDIO_PMA_EXTABLE_1000BKX)
 226                         ecmd->supported |= SUPPORTED_1000baseKX_Full;
 227                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 228                                       MDIO_PMA_10GBR_FECABLE);
 229                 if (reg & MDIO_PMA_10GBR_FECABLE_ABLE)
 230                         ecmd->supported |= SUPPORTED_10000baseR_FEC;
 231                 ecmd->advertising = ADVERTISED_Backplane;
 232                 break;
 233
 234         /* All the other defined modes are flavours of optical */
 235         default:
 236                 ecmd->port = PORT_FIBRE;
 237                 ecmd->supported = SUPPORTED_FIBRE;
 238                 ecmd->advertising = ADVERTISED_FIBRE;
 239                 break;
 240         }
 241
 242         if (mdio->mmds & MDIO_DEVS_AN) {
 243                 ecmd->supported |= SUPPORTED_Autoneg;
 244                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 245                                       MDIO_CTRL1);
 246                 if (reg & MDIO_AN_CTRL1_ENABLE) {
 247                         ecmd->autoneg = AUTONEG_ENABLE;
 248                         ecmd->advertising |=
 249                                 ADVERTISED_Autoneg |
 250                                 mdio45_get_an(mdio, MDIO_AN_ADVERTISE) |
 251                                 npage_adv;
 252                 } else {
 253                         ecmd->autoneg = AUTONEG_DISABLE;
 254                 }
 255         } else {
 256                 ecmd->autoneg = AUTONEG_DISABLE;
 257         }
 258
 259         if (ecmd->autoneg) {
 260                 u32 modes = 0;
 261                 int an_stat = mdio->mdio_read(mdio->dev, mdio->prtad,
 262                                               MDIO_MMD_AN, MDIO_STAT1);
 263
 264                 /* If AN is complete and successful, report best common
 265                  * mode, otherwise report best advertised mode. */
 266                 if (an_stat & MDIO_AN_STAT1_COMPLETE) {
 267                         ecmd->lp_advertising =
 268                                 mdio45_get_an(mdio, MDIO_AN_LPA) | npage_lpa;
 269                         if (an_stat & MDIO_AN_STAT1_LPABLE)
 270                                 ecmd->lp_advertising |= ADVERTISED_Autoneg;
 271                         modes = ecmd->advertising & ecmd->lp_advertising;
 272                 }
 273                 if ((modes & ~ADVERTISED_Autoneg) == 0)
 274                         modes = ecmd->advertising;
 275
 276                 if (modes & (ADVERTISED_10000baseT_Full |
 277                              ADVERTISED_10000baseKX4_Full |
 278                              ADVERTISED_10000baseKR_Full)) {
 279                         ecmd->speed = SPEED_10000;
 280                         ecmd->duplex = DUPLEX_FULL;
 281                 } else if (modes & (ADVERTISED_1000baseT_Full |
 282                                     ADVERTISED_1000baseT_Half |
 283                                     ADVERTISED_1000baseKX_Full)) {
 284                         ecmd->speed = SPEED_1000;
 285                         ecmd->duplex = !(modes & ADVERTISED_1000baseT_Half);
 286                 } else if (modes & (ADVERTISED_100baseT_Full |
 287                                     ADVERTISED_100baseT_Half)) {
 288                         ecmd->speed = SPEED_100;
 289                         ecmd->duplex = !!(modes & ADVERTISED_100baseT_Full);
 290                 } else {
 291                         ecmd->speed = SPEED_10;
 292                         ecmd->duplex = !!(modes & ADVERTISED_10baseT_Full);
 293                 }
 294         } else {
 295                 /* Report forced settings */
 296                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 297                                       MDIO_CTRL1);
 298                 ecmd->speed = (((reg & MDIO_PMA_CTRL1_SPEED1000) ? 100 : 1) *
 299                                ((reg & MDIO_PMA_CTRL1_SPEED100) ? 100 : 10));
 300                 ecmd->duplex = (reg & MDIO_CTRL1_FULLDPLX ||
 301                                 ecmd->speed == SPEED_10000);
 302         }
 303
 304         /* 10GBASE-T MDI/MDI-X */
 305         if (ecmd->port == PORT_TP && ecmd->speed == SPEED_10000) {
 306                 switch (mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 307                                         MDIO_PMA_10GBT_SWAPPOL)) {
 308                 case MDIO_PMA_10GBT_SWAPPOL_ABNX | MDIO_PMA_10GBT_SWAPPOL_CDNX:
 309                         ecmd->eth_tp_mdix = ETH_TP_MDI;
 310                         break;
 311                 case 0:
 312                         ecmd->eth_tp_mdix = ETH_TP_MDI_X;
 313                         break;
 314                 default:
 315                         /* It's complicated... */
 316                         ecmd->eth_tp_mdix = ETH_TP_MDI_INVALID;
 317                         break;
 318                 }
 319         }
 320 }
 321 EXPORT_SYMBOL(mdio45_ethtool_gset_npage);
 322
 323 /**
 324  * mdio45_ethtool_spauseparam_an - set auto-negotiated pause parameters
 325  * @mdio: MDIO interface
 326  * @ecmd: Ethtool request structure
 327  *
 328  * This function assumes that the PHY has an auto-negotiation MMD.  It
 329  * will enable and disable advertising of flow control as appropriate.
 330  */
 331 void mdio45_ethtool_spauseparam_an(const struct mdio_if_info *mdio,
 332                                    const struct ethtool_pauseparam *ecmd)
 333 {
 334         int adv, old_adv;
 335
 336         WARN_ON(!(mdio->mmds & MDIO_DEVS_AN));
 337
 338         old_adv = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 339                                   MDIO_AN_ADVERTISE);
 340         adv = old_adv & ~(ADVERTISE_PAUSE_CAP | ADVERTISE_PAUSE_ASYM);
 341         if (ecmd->autoneg)
 342                 adv |= mii_advertise_flowctrl(
 343                         (ecmd->rx_pause ? FLOW_CTRL_RX : 0) |
 344                         (ecmd->tx_pause ? FLOW_CTRL_TX : 0));
 345         if (adv != old_adv) {
 346                 mdio->mdio_write(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 347                                  MDIO_AN_ADVERTISE, adv);
 348                 mdio45_nway_restart(mdio);
 349         }
 350 }
 351 EXPORT_SYMBOL(mdio45_ethtool_spauseparam_an);
 352
 353 /**
 354  * mdio_mii_ioctl - MII ioctl interface for MDIO (clause 22 or 45) PHYs
 355  * @mdio: MDIO interface
 356  * @mii_data: MII ioctl data structure
 357  * @cmd: MII ioctl command
 358  *
 359  * Returns 0 on success, negative on error.
 360  */
 361 int mdio_mii_ioctl(const struct mdio_if_info *mdio,
 362                    struct mii_ioctl_data *mii_data, int cmd)
 363 {
 364         int prtad, devad;
 365         u16 addr = mii_data->reg_num;
 366
 367         /* Validate/convert cmd to one of SIOC{G,S}MIIREG */
 368         switch (cmd) {
 369         case SIOCGMIIPHY:
 370                 if (mdio->prtad == MDIO_PRTAD_NONE)
 371                         return -EOPNOTSUPP;
 372                 mii_data->phy_id = mdio->prtad;
 373                 cmd = SIOCGMIIREG;
 374                 break;
 375         case SIOCGMIIREG:
 376                 break;
 377         case SIOCSMIIREG:
 378                 if (!capable(CAP_NET_ADMIN))
 379                         return -EPERM;
 380                 break;
 381         default:
 382                 return -EOPNOTSUPP;
 383         }
 384
 385         /* Validate/convert phy_id */
 386         if ((mdio->mode_support & MDIO_SUPPORTS_C45) &&
 387             mdio_phy_id_is_c45(mii_data->phy_id)) {
 388                 prtad = mdio_phy_id_prtad(mii_data->phy_id);
 389                 devad = mdio_phy_id_devad(mii_data->phy_id);
 390         } else if ((mdio->mode_support & MDIO_SUPPORTS_C22) &&
 391                    mii_data->phy_id < 0x20) {
 392                 prtad = mii_data->phy_id;
 393                 devad = MDIO_DEVAD_NONE;
 394                 addr &= 0x1f;
 395         } else if ((mdio->mode_support & MDIO_EMULATE_C22) &&
 396                    mdio->prtad != MDIO_PRTAD_NONE &&
 397                    mii_data->phy_id == mdio->prtad) {
 398                 /* Remap commonly-used MII registers. */
 399                 prtad = mdio->prtad;
 400                 switch (addr) {
 401                 case MII_BMCR:
 402                 case MII_BMSR:
 403                 case MII_PHYSID1:
 404                 case MII_PHYSID2:
 405                         devad = __ffs(mdio->mmds);
 406                         break;
 407                 case MII_ADVERTISE:
 408                 case MII_LPA:
 409                         if (!(mdio->mmds & MDIO_DEVS_AN))
 410                                 return -EINVAL;
 411                         devad = MDIO_MMD_AN;
 412                         if (addr == MII_ADVERTISE)
 413                                 addr = MDIO_AN_ADVERTISE;
 414                         else
 415                                 addr = MDIO_AN_LPA;
 416                         break;
 417                 default:
 418                         return -EINVAL;
 419                 }
 420         } else {
 421                 return -EINVAL;
 422         }
 423
 424         if (cmd == SIOCGMIIREG) {
 425                 int rc = mdio->mdio_read(mdio->dev, prtad, devad, addr);
 426                 if (rc < 0)
 427                         return rc;
 428                 mii_data->val_out = rc;
 429                 return 0;
 430         } else {
 431                 return mdio->mdio_write(mdio->dev, prtad, devad, addr,
 432                                         mii_data->val_in);
 433         }
 434 }
 435 EXPORT_SYMBOL(mdio_mii_ioctl);