drivers/net/mdio.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * mdio.c: Generic support for MDIO-compatible transceivers
   4  * Copyright 2006-2009 Solarflare Communications Inc.
   5  */
   6
   7 #include <linux/kernel.h>
   8 #include <linux/capability.h>
   9 #include <linux/errno.h>
  10 #include <linux/ethtool.h>
  11 #include <linux/mdio.h>
  12 #include <linux/module.h>
  13
  14 MODULE_DESCRIPTION("Generic support for MDIO-compatible transceivers");
  15 MODULE_AUTHOR("Copyright 2006-2009 Solarflare Communications Inc.");
  16 MODULE_LICENSE("GPL");
  17
  18 /**
  19  * mdio45_probe - probe for an MDIO (clause 45) device
  20  * @mdio: MDIO interface
  21  * @prtad: Expected PHY address
  22  *
  23  * This sets @prtad and @mmds in the MDIO interface if successful.
  24  * Returns 0 on success, negative on error.
  25  */
  26 int mdio45_probe(struct mdio_if_info *mdio, int prtad)
  27 {
  28         int mmd, stat2, devs1, devs2;
  29
  30         /* Assume PHY must have at least one of PMA/PMD, WIS, PCS, PHY
  31          * XS or DTE XS; give up if none is present. */
  32         for (mmd = 1; mmd <= 5; mmd++) {
  33                 /* Is this MMD present? */
  34                 stat2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_STAT2);
  35                 if (stat2 < 0 ||
  36                     (stat2 & MDIO_STAT2_DEVPRST) != MDIO_STAT2_DEVPRST_VAL)
  37                         continue;
  38
  39                 /* It should tell us about all the other MMDs */
  40                 devs1 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS1);
  41                 devs2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS2);
  42                 if (devs1 < 0 || devs2 < 0)
  43                         continue;
  44
  45                 mdio->prtad = prtad;
  46                 mdio->mmds = devs1 | (devs2 << 16);
  47                 return 0;
  48         }
  49
  50         return -ENODEV;
  51 }
  52 EXPORT_SYMBOL(mdio45_probe);
  53
  54 /**
  55  * mdio_set_flag - set or clear flag in an MDIO register
  56  * @mdio: MDIO interface
  57  * @prtad: PHY address
  58  * @devad: MMD address
  59  * @addr: Register address
  60  * @mask: Mask for flag (single bit set)
  61  * @sense: New value of flag
  62  *
  63  * This debounces changes: it does not write the register if the flag
  64  * already has the proper value.  Returns 0 on success, negative on error.
  65  */
  66 int mdio_set_flag(const struct mdio_if_info *mdio,
  67                   int prtad, int devad, u16 addr, int mask,
  68                   bool sense)
  69 {
  70         int old_val = mdio->mdio_read(mdio->dev, prtad, devad, addr);
  71         int new_val;
  72
  73         if (old_val < 0)
  74                 return old_val;
  75         if (sense)
  76                 new_val = old_val | mask;
  77         else
  78                 new_val = old_val & ~mask;
  79         if (old_val == new_val)
  80                 return 0;
  81         return mdio->mdio_write(mdio->dev, prtad, devad, addr, new_val);
  82 }
  83 EXPORT_SYMBOL(mdio_set_flag);
  84
  85 /**
  86  * mdio45_links_ok - is link status up/OK
  87  * @mdio: MDIO interface
  88  * @mmd_mask: Mask for MMDs to check
  89  *
  90  * Returns 1 if the PHY reports link status up/OK, 0 otherwise.
  91  * @mmd_mask is normally @mdio->mmds, but if loopback is enabled
  92  * the MMDs being bypassed should be excluded from the mask.
  93  */
  94 int mdio45_links_ok(const struct mdio_if_info *mdio, u32 mmd_mask)
  95 {
  96         int devad, reg;
  97
  98         if (!mmd_mask) {
  99                 /* Use absence of XGMII faults in lieu of link state */
 100                 reg = mdio->mdio_read(mdio->dev, mdio->prtad,
 101                                       MDIO_MMD_PHYXS, MDIO_STAT2);
 102                 return reg >= 0 && !(reg & MDIO_STAT2_RXFAULT);
 103         }
 104
 105         for (devad = 0; mmd_mask; devad++) {
 106                 if (mmd_mask & (1 << devad)) {
 107                         mmd_mask &= ~(1 << devad);
 108
 109                         /* Reset the latched status and fault flags */
 110                         mdio->mdio_read(mdio->dev, mdio->prtad,
 111                                         devad, MDIO_STAT1);
 112                         if (devad == MDIO_MMD_PMAPMD || devad == MDIO_MMD_PCS ||
 113                             devad == MDIO_MMD_PHYXS || devad == MDIO_MMD_DTEXS)
 114                                 mdio->mdio_read(mdio->dev, mdio->prtad,
 115                                                 devad, MDIO_STAT2);
 116
 117                         /* Check the current status and fault flags */
 118                         reg = mdio->mdio_read(mdio->dev, mdio->prtad,
 119                                               devad, MDIO_STAT1);
 120                         if (reg < 0 ||
 121                             (reg & (MDIO_STAT1_FAULT | MDIO_STAT1_LSTATUS)) !=
 122                             MDIO_STAT1_LSTATUS)
 123                                 return false;
 124                 }
 125         }
 126
 127         return true;
 128 }
 129 EXPORT_SYMBOL(mdio45_links_ok);
 130
 131 /**
 132  * mdio45_nway_restart - restart auto-negotiation for this interface
 133  * @mdio: MDIO interface
 134  *
 135  * Returns 0 on success, negative on error.
 136  */
 137 int mdio45_nway_restart(const struct mdio_if_info *mdio)
 138 {
 139         if (!(mdio->mmds & MDIO_DEVS_AN))
 140                 return -EOPNOTSUPP;
 141
 142         mdio_set_flag(mdio, mdio->prtad, MDIO_MMD_AN, MDIO_CTRL1,
 143                       MDIO_AN_CTRL1_RESTART, true);
 144         return 0;
 145 }
 146 EXPORT_SYMBOL(mdio45_nway_restart);
 147
 148 static u32 mdio45_get_an(const struct mdio_if_info *mdio, u16 addr)
 149 {
 150         u32 result = 0;
 151         int reg;
 152
 153         reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN, addr);
 154         if (reg & ADVERTISE_10HALF)
 155                 result |= ADVERTISED_10baseT_Half;
 156         if (reg & ADVERTISE_10FULL)
 157                 result |= ADVERTISED_10baseT_Full;
 158         if (reg & ADVERTISE_100HALF)
 159                 result |= ADVERTISED_100baseT_Half;
 160         if (reg & ADVERTISE_100FULL)
 161                 result |= ADVERTISED_100baseT_Full;
 162         if (reg & ADVERTISE_PAUSE_CAP)
 163                 result |= ADVERTISED_Pause;
 164         if (reg & ADVERTISE_PAUSE_ASYM)
 165                 result |= ADVERTISED_Asym_Pause;
 166         return result;
 167 }
 168
 169 /**
 170  * mdio45_ethtool_ksettings_get_npage - get settings for ETHTOOL_GLINKSETTINGS
 171  * @mdio: MDIO interface
 172  * @cmd: Ethtool request structure
 173  * @npage_adv: Modes currently advertised on next pages
 174  * @npage_lpa: Modes advertised by link partner on next pages
 175  *
 176  * The @cmd parameter is expected to have been cleared before calling
 177  * mdio45_ethtool_ksettings_get_npage().
 178  *
 179  * Since the CSRs for auto-negotiation using next pages are not fully
 180  * standardised, this function does not attempt to decode them.  The
 181  * caller must pass them in.
 182  */
 183 void mdio45_ethtool_ksettings_get_npage(const struct mdio_if_info *mdio,
 184                                         struct ethtool_link_ksettings *cmd,
 185                                         u32 npage_adv, u32 npage_lpa)
 186 {
 187         int reg;
 188         u32 speed, supported = 0, advertising = 0, lp_advertising = 0;
 189
 190         BUILD_BUG_ON(MDIO_SUPPORTS_C22 != ETH_MDIO_SUPPORTS_C22);
 191         BUILD_BUG_ON(MDIO_SUPPORTS_C45 != ETH_MDIO_SUPPORTS_C45);
 192
 193         cmd->base.phy_address = mdio->prtad;
 194         cmd->base.mdio_support =
 195                 mdio->mode_support & (MDIO_SUPPORTS_C45 | MDIO_SUPPORTS_C22);
 196
 197         reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 198                               MDIO_CTRL2);
 199         switch (reg & MDIO_PMA_CTRL2_TYPE) {
 200         case MDIO_PMA_CTRL2_10GBT:
 201         case MDIO_PMA_CTRL2_1000BT:
 202         case MDIO_PMA_CTRL2_100BTX:
 203         case MDIO_PMA_CTRL2_10BT:
 204                 cmd->base.port = PORT_TP;
 205                 supported = SUPPORTED_TP;
 206                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 207                                       MDIO_SPEED);
 208                 if (reg & MDIO_SPEED_10G)
 209                         supported |= SUPPORTED_10000baseT_Full;
 210                 if (reg & MDIO_PMA_SPEED_1000)
 211                         supported |= (SUPPORTED_1000baseT_Full |
 212                                             SUPPORTED_1000baseT_Half);
 213                 if (reg & MDIO_PMA_SPEED_100)
 214                         supported |= (SUPPORTED_100baseT_Full |
 215                                             SUPPORTED_100baseT_Half);
 216                 if (reg & MDIO_PMA_SPEED_10)
 217                         supported |= (SUPPORTED_10baseT_Full |
 218                                             SUPPORTED_10baseT_Half);
 219                 advertising = ADVERTISED_TP;
 220                 break;
 221
 222         case MDIO_PMA_CTRL2_10GBCX4:
 223                 cmd->base.port = PORT_OTHER;
 224                 supported = 0;
 225                 advertising = 0;
 226                 break;
 227
 228         case MDIO_PMA_CTRL2_10GBKX4:
 229         case MDIO_PMA_CTRL2_10GBKR:
 230         case MDIO_PMA_CTRL2_1000BKX:
 231                 cmd->base.port = PORT_OTHER;
 232                 supported = SUPPORTED_Backplane;
 233                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 234                                       MDIO_PMA_EXTABLE);
 235                 if (reg & MDIO_PMA_EXTABLE_10GBKX4)
 236                         supported |= SUPPORTED_10000baseKX4_Full;
 237                 if (reg & MDIO_PMA_EXTABLE_10GBKR)
 238                         supported |= SUPPORTED_10000baseKR_Full;
 239                 if (reg & MDIO_PMA_EXTABLE_1000BKX)
 240                         supported |= SUPPORTED_1000baseKX_Full;
 241                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 242                                       MDIO_PMA_10GBR_FECABLE);
 243                 if (reg & MDIO_PMA_10GBR_FECABLE_ABLE)
 244                         supported |= SUPPORTED_10000baseR_FEC;
 245                 advertising = ADVERTISED_Backplane;
 246                 break;
 247
 248         /* All the other defined modes are flavours of optical */
 249         default:
 250                 cmd->base.port = PORT_FIBRE;
 251                 supported = SUPPORTED_FIBRE;
 252                 advertising = ADVERTISED_FIBRE;
 253                 break;
 254         }
 255
 256         if (mdio->mmds & MDIO_DEVS_AN) {
 257                 supported |= SUPPORTED_Autoneg;
 258                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
 259                                       MDIO_CTRL1);
 260                 if (reg & MDIO_AN_CTRL1_ENABLE) {
 261                         cmd->base.autoneg = AUTONEG_ENABLE;
 262                         advertising |=
 263                                 ADVERTISED_Autoneg |
 264                                 mdio45_get_an(mdio, MDIO_AN_ADVERTISE) |
 265                                 npage_adv;
 266                 } else {
 267                         cmd->base.autoneg = AUTONEG_DISABLE;
 268                 }
 269         } else {
 270                 cmd->base.autoneg = AUTONEG_DISABLE;
 271         }
 272
 273         if (cmd->base.autoneg) {
 274                 u32 modes = 0;
 275                 int an_stat = mdio->mdio_read(mdio->dev, mdio->prtad,
 276                                               MDIO_MMD_AN, MDIO_STAT1);
 277
 278                 /* If AN is complete and successful, report best common
 279                  * mode, otherwise report best advertised mode.
 280                  */
 281                 if (an_stat & MDIO_AN_STAT1_COMPLETE) {
 282                         lp_advertising =
 283                                 mdio45_get_an(mdio, MDIO_AN_LPA) | npage_lpa;
 284                         if (an_stat & MDIO_AN_STAT1_LPABLE)
 285                                 lp_advertising |= ADVERTISED_Autoneg;
 286                         modes = advertising & lp_advertising;
 287                 }
 288                 if ((modes & ~ADVERTISED_Autoneg) == 0)
 289                         modes = advertising;
 290
 291                 if (modes & (ADVERTISED_10000baseT_Full |
 292                              ADVERTISED_10000baseKX4_Full |
 293                              ADVERTISED_10000baseKR_Full)) {
 294                         speed = SPEED_10000;
 295                         cmd->base.duplex = DUPLEX_FULL;
 296                 } else if (modes & (ADVERTISED_1000baseT_Full |
 297                                     ADVERTISED_1000baseT_Half |
 298                                     ADVERTISED_1000baseKX_Full)) {
 299                         speed = SPEED_1000;
 300                         cmd->base.duplex = !(modes & ADVERTISED_1000baseT_Half);
 301                 } else if (modes & (ADVERTISED_100baseT_Full |
 302                                     ADVERTISED_100baseT_Half)) {
 303                         speed = SPEED_100;
 304                         cmd->base.duplex = !!(modes & ADVERTISED_100baseT_Full);
 305                 } else {
 306                         speed = SPEED_10;
 307                         cmd->base.duplex = !!(modes & ADVERTISED_10baseT_Full);
 308                 }
 309         } else {
 310                 /* Report forced settings */
 311                 reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 312                                       MDIO_CTRL1);
 313                 speed = (((reg & MDIO_PMA_CTRL1_SPEED1000) ? 100 : 1)
 314                          * ((reg & MDIO_PMA_CTRL1_SPEED100) ? 100 : 10));
 315                 cmd->base.duplex = (reg & MDIO_CTRL1_FULLDPLX ||
 316                                     speed == SPEED_10000);
 317         }
 318
 319         cmd->base.speed = speed;
 320
 321         ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
 322                                                 supported);
 323         ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.advertising,
 324                                                 advertising);
 325         ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.lp_advertising,
 326                                                 lp_advertising);
 327
 328         /* 10GBASE-T MDI/MDI-X */
 329         if (cmd->base.port == PORT_TP && (cmd->base.speed == SPEED_10000)) {
 330                 switch (mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
 331                                         MDIO_PMA_10GBT_SWAPPOL)) {
 332                 case MDIO_PMA_10GBT_SWAPPOL_ABNX | MDIO_PMA_10GBT_SWAPPOL_CDNX:
 333                         cmd->base.eth_tp_mdix = ETH_TP_MDI;
 334                         break;
 335                 case 0:
 336                         cmd->base.eth_tp_mdix = ETH_TP_MDI_X;
 337                         break;
 338                 default:
 339                         /* It's complicated... */
 340                         cmd->base.eth_tp_mdix = ETH_TP_MDI_INVALID;
 341                         break;
 342                 }
 343         }
 344 }
 345 EXPORT_SYMBOL(mdio45_ethtool_ksettings_get_npage);
 346
 347 /**
 348  * mdio_mii_ioctl - MII ioctl interface for MDIO (clause 22 or 45) PHYs
 349  * @mdio: MDIO interface
 350  * @mii_data: MII ioctl data structure
 351  * @cmd: MII ioctl command
 352  *
 353  * Returns 0 on success, negative on error.
 354  */
 355 int mdio_mii_ioctl(const struct mdio_if_info *mdio,
 356                    struct mii_ioctl_data *mii_data, int cmd)
 357 {
 358         int prtad, devad;
 359         u16 addr = mii_data->reg_num;
 360
 361         /* Validate/convert cmd to one of SIOC{G,S}MIIREG */
 362         switch (cmd) {
 363         case SIOCGMIIPHY:
 364                 if (mdio->prtad == MDIO_PRTAD_NONE)
 365                         return -EOPNOTSUPP;
 366                 mii_data->phy_id = mdio->prtad;
 367                 cmd = SIOCGMIIREG;
 368                 break;
 369         case SIOCGMIIREG:
 370         case SIOCSMIIREG:
 371                 break;
 372         default:
 373                 return -EOPNOTSUPP;
 374         }
 375
 376         /* Validate/convert phy_id */
 377         if ((mdio->mode_support & MDIO_SUPPORTS_C45) &&
 378             mdio_phy_id_is_c45(mii_data->phy_id)) {
 379                 prtad = mdio_phy_id_prtad(mii_data->phy_id);
 380                 devad = mdio_phy_id_devad(mii_data->phy_id);
 381         } else if ((mdio->mode_support & MDIO_SUPPORTS_C22) &&
 382                    mii_data->phy_id < 0x20) {
 383                 prtad = mii_data->phy_id;
 384                 devad = MDIO_DEVAD_NONE;
 385                 addr &= 0x1f;
 386         } else if ((mdio->mode_support & MDIO_EMULATE_C22) &&
 387                    mdio->prtad != MDIO_PRTAD_NONE &&
 388                    mii_data->phy_id == mdio->prtad) {
 389                 /* Remap commonly-used MII registers. */
 390                 prtad = mdio->prtad;
 391                 switch (addr) {
 392                 case MII_BMCR:
 393                 case MII_BMSR:
 394                 case MII_PHYSID1:
 395                 case MII_PHYSID2:
 396                         devad = __ffs(mdio->mmds);
 397                         break;
 398                 case MII_ADVERTISE:
 399                 case MII_LPA:
 400                         if (!(mdio->mmds & MDIO_DEVS_AN))
 401                                 return -EINVAL;
 402                         devad = MDIO_MMD_AN;
 403                         if (addr == MII_ADVERTISE)
 404                                 addr = MDIO_AN_ADVERTISE;
 405                         else
 406                                 addr = MDIO_AN_LPA;
 407                         break;
 408                 default:
 409                         return -EINVAL;
 410                 }
 411         } else {
 412                 return -EINVAL;
 413         }
 414
 415         if (cmd == SIOCGMIIREG) {
 416                 int rc = mdio->mdio_read(mdio->dev, prtad, devad, addr);
 417                 if (rc < 0)
 418                         return rc;
 419                 mii_data->val_out = rc;
 420                 return 0;
 421         } else {
 422                 return mdio->mdio_write(mdio->dev, prtad, devad, addr,
 423                                         mii_data->val_in);
 424         }
 425 }
 426 EXPORT_SYMBOL(mdio_mii_ioctl);