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  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18  */
  19
  20
  21 #include <linux/types.h>
  22 #include <linux/delay.h>
  23 #include <linux/wait.h>
  24 #include <linux/mii.h>
  25 #include <linux/ethtool.h>
  26 #include <linux/bitops.h>
  27 #include <linux/netdevice.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/phy.h>
  30 #include <linux/phy_fixed.h>
  31 #include <linux/brcmphy.h>
  32 #include <linux/of.h>
  33 #include <linux/of_net.h>
  34 #include <linux/of_mdio.h>
  35
  36 #include "bcmgenet.h"
  37
  38 /* read a value from the MII */
  39 static int bcmgenet_mii_read(struct mii_bus *bus, int phy_id, int location)
  40 {
  41         int ret;
  42         struct net_device *dev = bus->priv;
  43         struct bcmgenet_priv *priv = netdev_priv(dev);
  44         u32 reg;
  45
  46         bcmgenet_umac_writel(priv, (MDIO_RD | (phy_id << MDIO_PMD_SHIFT) |
  47                         (location << MDIO_REG_SHIFT)), UMAC_MDIO_CMD);
  48         /* Start MDIO transaction*/
  49         reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  50         reg |= MDIO_START_BUSY;
  51         bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
  52         wait_event_timeout(priv->wq,
  53                         !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
  54                                 & MDIO_START_BUSY),
  55                         HZ / 100);
  56         ret = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  57
  58         if (ret & MDIO_READ_FAIL)
  59                 return -EIO;
  60
  61         return ret & 0xffff;
  62 }
  63
  64 /* write a value to the MII */
  65 static int bcmgenet_mii_write(struct mii_bus *bus, int phy_id,
  66                         int location, u16 val)
  67 {
  68         struct net_device *dev = bus->priv;
  69         struct bcmgenet_priv *priv = netdev_priv(dev);
  70         u32 reg;
  71
  72         bcmgenet_umac_writel(priv, (MDIO_WR | (phy_id << MDIO_PMD_SHIFT) |
  73                         (location << MDIO_REG_SHIFT) | (0xffff & val)),
  74                         UMAC_MDIO_CMD);
  75         reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
  76         reg |= MDIO_START_BUSY;
  77         bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
  78         wait_event_timeout(priv->wq,
  79                         !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD) &
  80                                 MDIO_START_BUSY),
  81                         HZ / 100);
  82
  83         return 0;
  84 }
  85
  86 /* setup netdev link state when PHY link status change and
  87  * update UMAC and RGMII block when link up
  88  */
  89 static void bcmgenet_mii_setup(struct net_device *dev)
  90 {
  91         struct bcmgenet_priv *priv = netdev_priv(dev);
  92         struct phy_device *phydev = priv->phydev;
  93         u32 reg, cmd_bits = 0;
  94         unsigned int status_changed = 0;
  95
  96         if (priv->old_link != phydev->link) {
  97                 status_changed = 1;
  98                 priv->old_link = phydev->link;
  99         }
 100
 101         if (phydev->link) {
 102                 /* program UMAC and RGMII block based on established link
 103                  * speed, pause, and duplex.
 104                  * the speed set in umac->cmd tell RGMII block which clock
 105                  * 25MHz(100Mbps)/125MHz(1Gbps) to use for transmit.
 106                  * receive clock is provided by PHY.
 107                  */
 108                 reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 109                 reg &= ~OOB_DISABLE;
 110                 reg |= RGMII_LINK;
 111                 bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
 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                 if (priv->old_duplex != phydev->duplex) {
 123                         status_changed = 1;
 124                         priv->old_duplex = phydev->duplex;
 125                 }
 126
 127                 /* duplex */
 128                 if (phydev->duplex != DUPLEX_FULL)
 129                         cmd_bits |= CMD_HD_EN;
 130
 131                 if (priv->old_pause != phydev->pause) {
 132                         status_changed = 1;
 133                         priv->old_pause = phydev->pause;
 134                 }
 135
 136                 /* pause capability */
 137                 if (!phydev->pause)
 138                         cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE;
 139
 140                 reg = bcmgenet_umac_readl(priv, UMAC_CMD);
 141                 reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
 142                                CMD_HD_EN |
 143                                CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE);
 144                 reg |= cmd_bits;
 145                 bcmgenet_umac_writel(priv, reg, UMAC_CMD);
 146         }
 147
 148         if (status_changed)
 149                 phy_print_status(phydev);
 150 }
 151
 152 void bcmgenet_mii_reset(struct net_device *dev)
 153 {
 154         struct bcmgenet_priv *priv = netdev_priv(dev);
 155
 156         if (priv->phydev) {
 157                 phy_init_hw(priv->phydev);
 158                 phy_start_aneg(priv->phydev);
 159         }
 160 }
 161
 162 static void bcmgenet_ephy_power_up(struct net_device *dev)
 163 {
 164         struct bcmgenet_priv *priv = netdev_priv(dev);
 165         u32 reg = 0;
 166
 167         /* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
 168         if (!GENET_IS_V4(priv))
 169                 return;
 170
 171         reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
 172         reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
 173         reg |= EXT_GPHY_RESET;
 174         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 175         mdelay(2);
 176
 177         reg &= ~EXT_GPHY_RESET;
 178         bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
 179         udelay(20);
 180 }
 181
 182 static void bcmgenet_internal_phy_setup(struct net_device *dev)
 183 {
 184         struct bcmgenet_priv *priv = netdev_priv(dev);
 185         u32 reg;
 186
 187         /* Power up EPHY */
 188         bcmgenet_ephy_power_up(dev);
 189         /* enable APD */
 190         reg = bcmgenet_ext_readl(priv, EXT_EXT_PWR_MGMT);
 191         reg |= EXT_PWR_DN_EN_LD;
 192         bcmgenet_ext_writel(priv, reg, EXT_EXT_PWR_MGMT);
 193         bcmgenet_mii_reset(dev);
 194 }
 195
 196 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
 197 {
 198         u32 reg;
 199
 200         /* Speed settings are set in bcmgenet_mii_setup() */
 201         reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
 202         reg |= LED_ACT_SOURCE_MAC;
 203         bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
 204 }
 205
 206 int bcmgenet_mii_config(struct net_device *dev)
 207 {
 208         struct bcmgenet_priv *priv = netdev_priv(dev);
 209         struct phy_device *phydev = priv->phydev;
 210         struct device *kdev = &priv->pdev->dev;
 211         const char *phy_name = NULL;
 212         u32 id_mode_dis = 0;
 213         u32 port_ctrl;
 214         u32 reg;
 215
 216         priv->ext_phy = !phy_is_internal(priv->phydev) &&
 217                         (priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
 218
 219         if (phy_is_internal(priv->phydev))
 220                 priv->phy_interface = PHY_INTERFACE_MODE_NA;
 221
 222         switch (priv->phy_interface) {
 223         case PHY_INTERFACE_MODE_NA:
 224         case PHY_INTERFACE_MODE_MOCA:
 225                 /* Irrespective of the actually configured PHY speed (100 or
 226                  * 1000) GENETv4 only has an internal GPHY so we will just end
 227                  * up masking the Gigabit features from what we support, not
 228                  * switching to the EPHY
 229                  */
 230                 if (GENET_IS_V4(priv))
 231                         port_ctrl = PORT_MODE_INT_GPHY;
 232                 else
 233                         port_ctrl = PORT_MODE_INT_EPHY;
 234
 235                 bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
 236
 237                 if (phy_is_internal(priv->phydev)) {
 238                         phy_name = "internal PHY";
 239                         bcmgenet_internal_phy_setup(dev);
 240                 } else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
 241                         phy_name = "MoCA";
 242                         bcmgenet_moca_phy_setup(priv);
 243                 }
 244                 break;
 245
 246         case PHY_INTERFACE_MODE_MII:
 247                 phy_name = "external MII";
 248                 phydev->supported &= PHY_BASIC_FEATURES;
 249                 bcmgenet_sys_writel(priv,
 250                                 PORT_MODE_EXT_EPHY, SYS_PORT_CTRL);
 251                 break;
 252
 253         case PHY_INTERFACE_MODE_REVMII:
 254                 phy_name = "external RvMII";
 255                 /* of_mdiobus_register took care of reading the 'max-speed'
 256                  * PHY property for us, effectively limiting the PHY supported
 257                  * capabilities, use that knowledge to also configure the
 258                  * Reverse MII interface correctly.
 259                  */
 260                 if ((priv->phydev->supported & PHY_BASIC_FEATURES) ==
 261                                 PHY_BASIC_FEATURES)
 262                         port_ctrl = PORT_MODE_EXT_RVMII_25;
 263                 else
 264                         port_ctrl = PORT_MODE_EXT_RVMII_50;
 265                 bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
 266                 break;
 267
 268         case PHY_INTERFACE_MODE_RGMII:
 269                 /* RGMII_NO_ID: TXC transitions at the same time as TXD
 270                  *              (requires PCB or receiver-side delay)
 271                  * RGMII:       Add 2ns delay on TXC (90 degree shift)
 272                  *
 273                  * ID is implicitly disabled for 100Mbps (RG)MII operation.
 274                  */
 275                 id_mode_dis = BIT(16);
 276                 /* fall through */
 277         case PHY_INTERFACE_MODE_RGMII_TXID:
 278                 if (id_mode_dis)
 279                         phy_name = "external RGMII (no delay)";
 280                 else
 281                         phy_name = "external RGMII (TX delay)";
 282                 reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
 283                 reg |= RGMII_MODE_EN | id_mode_dis;
 284                 bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
 285                 bcmgenet_sys_writel(priv,
 286                                 PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
 287                 break;
 288         default:
 289                 dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
 290                 return -EINVAL;
 291         }
 292
 293         dev_info(kdev, "configuring instance for %s\n", phy_name);
 294
 295         return 0;
 296 }
 297
 298 static int bcmgenet_mii_probe(struct net_device *dev)
 299 {
 300         struct bcmgenet_priv *priv = netdev_priv(dev);
 301         struct device_node *dn = priv->pdev->dev.of_node;
 302         struct phy_device *phydev;
 303         unsigned int phy_flags;
 304         int ret;
 305
 306         if (priv->phydev) {
 307                 pr_info("PHY already attached\n");
 308                 return 0;
 309         }
 310
 311         /* In the case of a fixed PHY, the DT node associated
 312          * to the PHY is the Ethernet MAC DT node.
 313          */
 314         if (of_phy_is_fixed_link(dn)) {
 315                 ret = of_phy_register_fixed_link(dn);
 316                 if (ret)
 317                         return ret;
 318
 319                 priv->phy_dn = dn;
 320         }
 321
 322         phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup, 0,
 323                                 priv->phy_interface);
 324         if (!phydev) {
 325                 pr_err("could not attach to PHY\n");
 326                 return -ENODEV;
 327         }
 328
 329         priv->old_link = -1;
 330         priv->old_duplex = -1;
 331         priv->old_pause = -1;
 332         priv->phydev = phydev;
 333
 334         /* Configure port multiplexer based on what the probed PHY device since
 335          * reading the 'max-speed' property determines the maximum supported
 336          * PHY speed which is needed for bcmgenet_mii_config() to configure
 337          * things appropriately.
 338          */
 339         ret = bcmgenet_mii_config(dev);
 340         if (ret) {
 341                 phy_disconnect(priv->phydev);
 342                 return ret;
 343         }
 344
 345         phy_flags = PHY_BRCM_100MBPS_WAR;
 346
 347         /* workarounds are only needed for 100Mpbs PHYs, and
 348          * never on GENET V1 hardware
 349          */
 350         if ((phydev->supported & PHY_GBIT_FEATURES) || GENET_IS_V1(priv))
 351                 phy_flags = 0;
 352
 353         phydev->dev_flags |= phy_flags;
 354         phydev->advertising = phydev->supported;
 355
 356         /* The internal PHY has its link interrupts routed to the
 357          * Ethernet MAC ISRs
 358          */
 359         if (phy_is_internal(priv->phydev))
 360                 priv->mii_bus->irq[phydev->addr] = PHY_IGNORE_INTERRUPT;
 361         else
 362                 priv->mii_bus->irq[phydev->addr] = PHY_POLL;
 363
 364         pr_info("attached PHY at address %d [%s]\n",
 365                         phydev->addr, phydev->drv->name);
 366
 367         return 0;
 368 }
 369
 370 static int bcmgenet_mii_alloc(struct bcmgenet_priv *priv)
 371 {
 372         struct mii_bus *bus;
 373
 374         if (priv->mii_bus)
 375                 return 0;
 376
 377         priv->mii_bus = mdiobus_alloc();
 378         if (!priv->mii_bus) {
 379                 pr_err("failed to allocate\n");
 380                 return -ENOMEM;
 381         }
 382
 383         bus = priv->mii_bus;
 384         bus->priv = priv->dev;
 385         bus->name = "bcmgenet MII bus";
 386         bus->parent = &priv->pdev->dev;
 387         bus->read = bcmgenet_mii_read;
 388         bus->write = bcmgenet_mii_write;
 389         snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d",
 390                         priv->pdev->name, priv->pdev->id);
 391
 392         bus->irq = kzalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
 393         if (!bus->irq) {
 394                 mdiobus_free(priv->mii_bus);
 395                 return -ENOMEM;
 396         }
 397
 398         return 0;
 399 }
 400
 401 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
 402 {
 403         struct device_node *dn = priv->pdev->dev.of_node;
 404         struct device *kdev = &priv->pdev->dev;
 405         struct device_node *mdio_dn;
 406         char *compat;
 407         int ret;
 408
 409         compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
 410         if (!compat)
 411                 return -ENOMEM;
 412
 413         mdio_dn = of_find_compatible_node(dn, NULL, compat);
 414         kfree(compat);
 415         if (!mdio_dn) {
 416                 dev_err(kdev, "unable to find MDIO bus node\n");
 417                 return -ENODEV;
 418         }
 419
 420         ret = of_mdiobus_register(priv->mii_bus, mdio_dn);
 421         if (ret) {
 422                 dev_err(kdev, "failed to register MDIO bus\n");
 423                 return ret;
 424         }
 425
 426         /* Fetch the PHY phandle */
 427         priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
 428
 429         /* Get the link mode */
 430         priv->phy_interface = of_get_phy_mode(dn);
 431
 432         return 0;
 433 }
 434
 435 int bcmgenet_mii_init(struct net_device *dev)
 436 {
 437         struct bcmgenet_priv *priv = netdev_priv(dev);
 438         int ret;
 439
 440         ret = bcmgenet_mii_alloc(priv);
 441         if (ret)
 442                 return ret;
 443
 444         ret = bcmgenet_mii_of_init(priv);
 445         if (ret)
 446                 goto out_free;
 447
 448         ret = bcmgenet_mii_probe(dev);
 449         if (ret)
 450                 goto out;
 451
 452         return 0;
 453
 454 out:
 455         mdiobus_unregister(priv->mii_bus);
 456 out_free:
 457         kfree(priv->mii_bus->irq);
 458         mdiobus_free(priv->mii_bus);
 459         return ret;
 460 }
 461
 462 void bcmgenet_mii_exit(struct net_device *dev)
 463 {
 464         struct bcmgenet_priv *priv = netdev_priv(dev);
 465
 466         mdiobus_unregister(priv->mii_bus);
 467         kfree(priv->mii_bus->irq);
 468         mdiobus_free(priv->mii_bus);
 469 }