drivers/net/ethernet/broadcom/genet/bcmmii.c

   1 /*
   2  * Broadcom GENET MDIO routines
   3  *
   4  * Copyright (c) 2014 Broadcom Corporation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11
  12 #include <linux/types.h>
  13 #include <linux/delay.h>
  14 #include <linux/wait.h>
  15 #include <linux/mii.h>
  16 #include <linux/ethtool.h>
  17 #include <linux/bitops.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/phy.h>
  21 #include <linux/phy_fixed.h>
  22 #include <linux/brcmphy.h>
  23 #include <linux/of.h>
  24 #include <linux/of_net.h>
  25 #include <linux/of_mdio.h>
  26
  27 #include "bcmgenet.h"
  28
  29 /* read a value from the MII */
  30 static int bcmgenet_mii_read(struct mii_bus *bus, int phy_id, int location)
  31 {
  32         int ret;
  33         struct net_device *dev = bus->priv;
  34         struct bcmgenet_priv *priv = netdev_priv(dev);
  35         u32 reg;
  36
  37         bcmgenet_umac_writel(priv, (MDIO_RD | (phy_id << MDIO_PMD_SHIFT) |
  38                              (location << MDIO_REG_SHIFT)), UMAC_MDIO_CMD);
  39         /* Start MDIO transaction*/
  40         reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  41         reg |= MDIO_START_BUSY;
  42         bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
  43         wait_event_timeout(priv->wq,
  44                            !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
  45                            & MDIO_START_BUSY),
  46                            HZ / 100);
  47         ret = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  48
  49         if (ret & MDIO_READ_FAIL)
  50                 return -EIO;
  51
  52         return ret & 0xffff;
  53 }
  54
  55 /* write a value to the MII */
  56 static int bcmgenet_mii_write(struct mii_bus *bus, int phy_id,
  57                               int location, u16 val)
  58 {
  59         struct net_device *dev = bus->priv;
  60         struct bcmgenet_priv *priv = netdev_priv(dev);
  61         u32 reg;
  62
  63         bcmgenet_umac_writel(priv, (MDIO_WR | (phy_id << MDIO_PMD_SHIFT) |
  64                              (location << MDIO_REG_SHIFT) | (0xffff & val)),
  65                              UMAC_MDIO_CMD);
  66         reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  67         reg |= MDIO_START_BUSY;
  68         bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
  69         wait_event_timeout(priv->wq,
  70                            !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD) &
  71                            MDIO_START_BUSY),
  72                            HZ / 100);
  73
  74         return 0;
  75 }
  76
  77 /* setup netdev link state when PHY link status change and
  78  * update UMAC and RGMII block when link up
  79  */
  80 static void bcmgenet_mii_setup(struct net_device *dev)
  81 {
  82         struct bcmgenet_priv *priv = netdev_priv(dev);
  83         struct phy_device *phydev = priv->phydev;
  84         u32 reg, cmd_bits = 0;
  85         bool status_changed = false;
  86
  87         if (priv->old_link != phydev->link) {
  88                 status_changed = true;
  89                 priv->old_link = phydev->link;
  90         }
  91
  92         if (phydev->link) {
  93                 /* check speed/duplex/pause changes */
  94                 if (priv->old_speed != phydev->speed) {
  95                         status_changed = true;
  96                         priv->old_speed = phydev->speed;
  97                 }
  98
  99                 if (priv->old_duplex != phydev->duplex) {
 100                         status_changed = true;
 101                         priv->old_duplex = phydev->duplex;
 102                 }
 103
 104                 if (priv->old_pause != phydev->pause) {
 105                         status_changed = true;
 106                         priv->old_pause = phydev->pause;
 107                 }
 108
 109                 /* done if nothing has changed */
 110                 if (!status_changed)
 111                         return;
 112
 113                 /* speed */
 114                 if (phydev->speed == SPEED_1000)
 115                         cmd_bits = UMAC_SPEED_1000;
 116                 else if (phydev->speed == SPEED_100)
 117                         cmd_bits = UMAC_SPEED_100;
 118                 else
 119                         cmd_bits = UMAC_SPEED_10;
 120                 cmd_bits <<= CMD_SPEED_SHIFT;
 121
 122                 /* duplex */
 123                 if (phydev->duplex != DUPLEX_FULL)
 124                         cmd_bits |= CMD_HD_EN;
 125
 126                 /* pause capability */
 127                 if (!phydev->pause)
 128                         cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE;
 129
 130                 /*
 131                  * Program UMAC and RGMII block based on established
 132                  * link speed, duplex, and pause. The speed set in
 133                  * umac->cmd tell RGMII block which clock to use for
 134                  * transmit -- 25MHz(100Mbps) or 125MHz(1Gbps).
 135                  * Receive clock is provided by the PHY.
 136                  */
 137                 reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 138                 reg &= ~OOB_DISABLE;
 139                 reg |= RGMII_LINK;
 140                 bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
 141
 142                 reg = bcmgenet_umac_readl(priv, UMAC_CMD);
 143                 reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
 144                                CMD_HD_EN |
 145                                CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE);
 146                 reg |= cmd_bits;
 147                 bcmgenet_umac_writel(priv, reg, UMAC_CMD);
 148         } else {
 149                 /* done if nothing has changed */
 150                 if (!status_changed)
 151                         return;
 152
 153                 /* needed for MoCA fixed PHY to reflect correct link status */
 154                 netif_carrier_off(dev);
 155         }
 156
 157         phy_print_status(phydev);
 158 }
 159
 160 void bcmgenet_mii_reset(struct net_device *dev)
 161 {
 162         struct bcmgenet_priv *priv = netdev_priv(dev);
 163
 164         if (priv->phydev) {
 165                 phy_init_hw(priv->phydev);
 166                 phy_start_aneg(priv->phydev);
 167         }
 168 }
 169
 170 static void bcmgenet_ephy_power_up(struct net_device *dev)
 171 {
 172         struct bcmgenet_priv *priv = netdev_priv(dev);
 173         u32 reg = 0;
 174
 175         /* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
 176         if (!GENET_IS_V4(priv))
 177                 return;
 178
 179         reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
 180         reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
 181         reg |= EXT_GPHY_RESET;
 182         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 183         mdelay(2);
 184
 185         reg &= ~EXT_GPHY_RESET;
 186         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 187         udelay(20);
 188 }
 189
 190 static void bcmgenet_internal_phy_setup(struct net_device *dev)
 191 {
 192         struct bcmgenet_priv *priv = netdev_priv(dev);
 193         u32 reg;
 194
 195         /* Power up EPHY */
 196         bcmgenet_ephy_power_up(dev);
 197         /* enable APD */
 198         reg = bcmgenet_ext_readl(priv, EXT_EXT_PWR_MGMT);
 199         reg |= EXT_PWR_DN_EN_LD;
 200         bcmgenet_ext_writel(priv, reg, EXT_EXT_PWR_MGMT);
 201         bcmgenet_mii_reset(dev);
 202 }
 203
 204 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
 205 {
 206         u32 reg;
 207
 208         /* Speed settings are set in bcmgenet_mii_setup() */
 209         reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
 210         reg |= LED_ACT_SOURCE_MAC;
 211         bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
 212 }
 213
 214 int bcmgenet_mii_config(struct net_device *dev)
 215 {
 216         struct bcmgenet_priv *priv = netdev_priv(dev);
 217         struct phy_device *phydev = priv->phydev;
 218         struct device *kdev = &priv->pdev->dev;
 219         const char *phy_name = NULL;
 220         u32 id_mode_dis = 0;
 221         u32 port_ctrl;
 222         u32 reg;
 223
 224         priv->ext_phy = !phy_is_internal(priv->phydev) &&
 225                         (priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
 226
 227         if (phy_is_internal(priv->phydev))
 228                 priv->phy_interface = PHY_INTERFACE_MODE_NA;
 229
 230         switch (priv->phy_interface) {
 231         case PHY_INTERFACE_MODE_NA:
 232         case PHY_INTERFACE_MODE_MOCA:
 233                 /* Irrespective of the actually configured PHY speed (100 or
 234                  * 1000) GENETv4 only has an internal GPHY so we will just end
 235                  * up masking the Gigabit features from what we support, not
 236                  * switching to the EPHY
 237                  */
 238                 if (GENET_IS_V4(priv))
 239                         port_ctrl = PORT_MODE_INT_GPHY;
 240                 else
 241                         port_ctrl = PORT_MODE_INT_EPHY;
 242
 243                 bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
 244
 245                 if (phy_is_internal(priv->phydev)) {
 246                         phy_name = "internal PHY";
 247                         bcmgenet_internal_phy_setup(dev);
 248                 } else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
 249                         phy_name = "MoCA";
 250                         bcmgenet_moca_phy_setup(priv);
 251                 }
 252                 break;
 253
 254         case PHY_INTERFACE_MODE_MII:
 255                 phy_name = "external MII";
 256                 phydev->supported &= PHY_BASIC_FEATURES;
 257                 bcmgenet_sys_writel(priv,
 258                                     PORT_MODE_EXT_EPHY, SYS_PORT_CTRL);
 259                 break;
 260
 261         case PHY_INTERFACE_MODE_REVMII:
 262                 phy_name = "external RvMII";
 263                 /* of_mdiobus_register took care of reading the 'max-speed'
 264                  * PHY property for us, effectively limiting the PHY supported
 265                  * capabilities, use that knowledge to also configure the
 266                  * Reverse MII interface correctly.
 267                  */
 268                 if ((priv->phydev->supported & PHY_BASIC_FEATURES) ==
 269                                 PHY_BASIC_FEATURES)
 270                         port_ctrl = PORT_MODE_EXT_RVMII_25;
 271                 else
 272                         port_ctrl = PORT_MODE_EXT_RVMII_50;
 273                 bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
 274                 break;
 275
 276         case PHY_INTERFACE_MODE_RGMII:
 277                 /* RGMII_NO_ID: TXC transitions at the same time as TXD
 278                  *              (requires PCB or receiver-side delay)
 279                  * RGMII:       Add 2ns delay on TXC (90 degree shift)
 280                  *
 281                  * ID is implicitly disabled for 100Mbps (RG)MII operation.
 282                  */
 283                 id_mode_dis = BIT(16);
 284                 /* fall through */
 285         case PHY_INTERFACE_MODE_RGMII_TXID:
 286                 if (id_mode_dis)
 287                         phy_name = "external RGMII (no delay)";
 288                 else
 289                         phy_name = "external RGMII (TX delay)";
 290                 reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 291                 reg |= RGMII_MODE_EN | id_mode_dis;
 292                 bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
 293                 bcmgenet_sys_writel(priv,
 294                                     PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
 295                 break;
 296         default:
 297                 dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
 298                 return -EINVAL;
 299         }
 300
 301         dev_info(kdev, "configuring instance for %s\n", phy_name);
 302
 303         return 0;
 304 }
 305
 306 static int bcmgenet_mii_probe(struct net_device *dev)
 307 {
 308         struct bcmgenet_priv *priv = netdev_priv(dev);
 309         struct device_node *dn = priv->pdev->dev.of_node;
 310         struct phy_device *phydev;
 311         u32 phy_flags;
 312         int ret;
 313
 314         if (priv->phydev) {
 315                 pr_info("PHY already attached\n");
 316                 return 0;
 317         }
 318
 319         /* In the case of a fixed PHY, the DT node associated
 320          * to the PHY is the Ethernet MAC DT node.
 321          */
 322         if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
 323                 ret = of_phy_register_fixed_link(dn);
 324                 if (ret)
 325                         return ret;
 326
 327                 priv->phy_dn = of_node_get(dn);
 328         }
 329
 330         /* Communicate the integrated PHY revision */
 331         phy_flags = priv->gphy_rev;
 332
 333         /* Initialize link state variables that bcmgenet_mii_setup() uses */
 334         priv->old_link = -1;
 335         priv->old_speed = -1;
 336         priv->old_duplex = -1;
 337         priv->old_pause = -1;
 338
 339         phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
 340                                 phy_flags, priv->phy_interface);
 341         if (!phydev) {
 342                 pr_err("could not attach to PHY\n");
 343                 return -ENODEV;
 344         }
 345
 346         priv->phydev = phydev;
 347
 348         /* Configure port multiplexer based on what the probed PHY device since
 349          * reading the 'max-speed' property determines the maximum supported
 350          * PHY speed which is needed for bcmgenet_mii_config() to configure
 351          * things appropriately.
 352          */
 353         ret = bcmgenet_mii_config(dev);
 354         if (ret) {
 355                 phy_disconnect(priv->phydev);
 356                 return ret;
 357         }
 358
 359         phydev->advertising = phydev->supported;
 360
 361         /* The internal PHY has its link interrupts routed to the
 362          * Ethernet MAC ISRs
 363          */
 364         if (phy_is_internal(priv->phydev))
 365                 priv->mii_bus->irq[phydev->addr] = PHY_IGNORE_INTERRUPT;
 366         else
 367                 priv->mii_bus->irq[phydev->addr] = PHY_POLL;
 368
 369         pr_info("attached PHY at address %d [%s]\n",
 370                 phydev->addr, phydev->drv->name);
 371
 372         return 0;
 373 }
 374
 375 static int bcmgenet_mii_alloc(struct bcmgenet_priv *priv)
 376 {
 377         struct mii_bus *bus;
 378
 379         if (priv->mii_bus)
 380                 return 0;
 381
 382         priv->mii_bus = mdiobus_alloc();
 383         if (!priv->mii_bus) {
 384                 pr_err("failed to allocate\n");
 385                 return -ENOMEM;
 386         }
 387
 388         bus = priv->mii_bus;
 389         bus->priv = priv->dev;
 390         bus->name = "bcmgenet MII bus";
 391         bus->parent = &priv->pdev->dev;
 392         bus->read = bcmgenet_mii_read;
 393         bus->write = bcmgenet_mii_write;
 394         snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d",
 395                  priv->pdev->name, priv->pdev->id);
 396
 397         bus->irq = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL);
 398         if (!bus->irq) {
 399                 mdiobus_free(priv->mii_bus);
 400                 return -ENOMEM;
 401         }
 402
 403         return 0;
 404 }
 405
 406 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
 407 {
 408         struct device_node *dn = priv->pdev->dev.of_node;
 409         struct device *kdev = &priv->pdev->dev;
 410         struct device_node *mdio_dn;
 411         char *compat;
 412         int ret;
 413
 414         compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
 415         if (!compat)
 416                 return -ENOMEM;
 417
 418         mdio_dn = of_find_compatible_node(dn, NULL, compat);
 419         kfree(compat);
 420         if (!mdio_dn) {
 421                 dev_err(kdev, "unable to find MDIO bus node\n");
 422                 return -ENODEV;
 423         }
 424
 425         ret = of_mdiobus_register(priv->mii_bus, mdio_dn);
 426         if (ret) {
 427                 dev_err(kdev, "failed to register MDIO bus\n");
 428                 return ret;
 429         }
 430
 431         /* Fetch the PHY phandle */
 432         priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
 433
 434         /* Get the link mode */
 435         priv->phy_interface = of_get_phy_mode(dn);
 436
 437         return 0;
 438 }
 439
 440 int bcmgenet_mii_init(struct net_device *dev)
 441 {
 442         struct bcmgenet_priv *priv = netdev_priv(dev);
 443         int ret;
 444
 445         ret = bcmgenet_mii_alloc(priv);
 446         if (ret)
 447                 return ret;
 448
 449         ret = bcmgenet_mii_of_init(priv);
 450         if (ret)
 451                 goto out_free;
 452
 453         ret = bcmgenet_mii_probe(dev);
 454         if (ret)
 455                 goto out;
 456
 457         return 0;
 458
 459 out:
 460         of_node_put(priv->phy_dn);
 461         mdiobus_unregister(priv->mii_bus);
 462 out_free:
 463         kfree(priv->mii_bus->irq);
 464         mdiobus_free(priv->mii_bus);
 465         return ret;
 466 }
 467
 468 void bcmgenet_mii_exit(struct net_device *dev)
 469 {
 470         struct bcmgenet_priv *priv = netdev_priv(dev);
 471
 472         of_node_put(priv->phy_dn);
 473         mdiobus_unregister(priv->mii_bus);
 474         kfree(priv->mii_bus->irq);
 475         mdiobus_free(priv->mii_bus);
 476 }