1 /******************************************************************************* 2 STMMAC Ethernet Driver -- MDIO bus implementation 3 Provides Bus interface for MII registers 4 5 Copyright (C) 2007-2009 STMicroelectronics Ltd 6 7 This program is free software; you can redistribute it and/or modify it 8 under the terms and conditions of the GNU General Public License, 9 version 2, as published by the Free Software Foundation. 10 11 This program is distributed in the hope it will be useful, but WITHOUT 12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 more details. 15 16 The full GNU General Public License is included in this distribution in 17 the file called "COPYING". 18 19 Author: Carl Shaw <carl.shaw@st.com> 20 Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com> 21 *******************************************************************************/ 22 23 #include <linux/io.h> 24 #include <linux/iopoll.h> 25 #include <linux/mii.h> 26 #include <linux/of.h> 27 #include <linux/of_gpio.h> 28 #include <linux/of_mdio.h> 29 #include <linux/phy.h> 30 #include <linux/slab.h> 31 32 #include "dwxgmac2.h" 33 #include "stmmac.h" 34 35 #define MII_BUSY 0x00000001 36 #define MII_WRITE 0x00000002 37 38 /* GMAC4 defines */ 39 #define MII_GMAC4_GOC_SHIFT 2 40 #define MII_GMAC4_WRITE (1 << MII_GMAC4_GOC_SHIFT) 41 #define MII_GMAC4_READ (3 << MII_GMAC4_GOC_SHIFT) 42 43 /* XGMAC defines */ 44 #define MII_XGMAC_SADDR BIT(18) 45 #define MII_XGMAC_CMD_SHIFT 16 46 #define MII_XGMAC_WRITE (1 << MII_XGMAC_CMD_SHIFT) 47 #define MII_XGMAC_READ (3 << MII_XGMAC_CMD_SHIFT) 48 #define MII_XGMAC_BUSY BIT(22) 49 #define MII_XGMAC_MAX_C22ADDR 3 50 #define MII_XGMAC_C22P_MASK GENMASK(MII_XGMAC_MAX_C22ADDR, 0) 51 52 static int stmmac_xgmac2_c22_format(struct stmmac_priv *priv, int phyaddr, 53 int phyreg, u32 *hw_addr) 54 { 55 unsigned int mii_data = priv->hw->mii.data; 56 u32 tmp; 57 58 /* HW does not support C22 addr >= 4 */ 59 if (phyaddr > MII_XGMAC_MAX_C22ADDR) 60 return -ENODEV; 61 /* Wait until any existing MII operation is complete */ 62 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp, 63 !(tmp & MII_XGMAC_BUSY), 100, 10000)) 64 return -EBUSY; 65 66 /* Set port as Clause 22 */ 67 tmp = readl(priv->ioaddr + XGMAC_MDIO_C22P); 68 tmp &= ~MII_XGMAC_C22P_MASK; 69 tmp |= BIT(phyaddr); 70 writel(tmp, priv->ioaddr + XGMAC_MDIO_C22P); 71 72 *hw_addr = (phyaddr << 16) | (phyreg & 0x1f); 73 return 0; 74 } 75 76 static int stmmac_xgmac2_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg) 77 { 78 struct net_device *ndev = bus->priv; 79 struct stmmac_priv *priv = netdev_priv(ndev); 80 unsigned int mii_address = priv->hw->mii.addr; 81 unsigned int mii_data = priv->hw->mii.data; 82 u32 tmp, addr, value = MII_XGMAC_BUSY; 83 int ret; 84 85 if (phyreg & MII_ADDR_C45) { 86 return -EOPNOTSUPP; 87 } else { 88 ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr); 89 if (ret) 90 return ret; 91 } 92 93 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift) 94 & priv->hw->mii.clk_csr_mask; 95 value |= MII_XGMAC_SADDR | MII_XGMAC_READ; 96 97 /* Wait until any existing MII operation is complete */ 98 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp, 99 !(tmp & MII_XGMAC_BUSY), 100, 10000)) 100 return -EBUSY; 101 102 /* Set the MII address register to read */ 103 writel(addr, priv->ioaddr + mii_address); 104 writel(value, priv->ioaddr + mii_data); 105 106 /* Wait until any existing MII operation is complete */ 107 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp, 108 !(tmp & MII_XGMAC_BUSY), 100, 10000)) 109 return -EBUSY; 110 111 /* Read the data from the MII data register */ 112 return readl(priv->ioaddr + mii_data) & GENMASK(15, 0); 113 } 114 115 static int stmmac_xgmac2_mdio_write(struct mii_bus *bus, int phyaddr, 116 int phyreg, u16 phydata) 117 { 118 struct net_device *ndev = bus->priv; 119 struct stmmac_priv *priv = netdev_priv(ndev); 120 unsigned int mii_address = priv->hw->mii.addr; 121 unsigned int mii_data = priv->hw->mii.data; 122 u32 addr, tmp, value = MII_XGMAC_BUSY; 123 int ret; 124 125 if (phyreg & MII_ADDR_C45) { 126 return -EOPNOTSUPP; 127 } else { 128 ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr); 129 if (ret) 130 return ret; 131 } 132 133 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift) 134 & priv->hw->mii.clk_csr_mask; 135 value |= phydata | MII_XGMAC_SADDR; 136 value |= MII_XGMAC_WRITE; 137 138 /* Wait until any existing MII operation is complete */ 139 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp, 140 !(tmp & MII_XGMAC_BUSY), 100, 10000)) 141 return -EBUSY; 142 143 /* Set the MII address register to write */ 144 writel(addr, priv->ioaddr + mii_address); 145 writel(value, priv->ioaddr + mii_data); 146 147 /* Wait until any existing MII operation is complete */ 148 return readl_poll_timeout(priv->ioaddr + mii_data, tmp, 149 !(tmp & MII_XGMAC_BUSY), 100, 10000); 150 } 151 152 /** 153 * stmmac_mdio_read 154 * @bus: points to the mii_bus structure 155 * @phyaddr: MII addr 156 * @phyreg: MII reg 157 * Description: it reads data from the MII register from within the phy device. 158 * For the 7111 GMAC, we must set the bit 0 in the MII address register while 159 * accessing the PHY registers. 160 * Fortunately, it seems this has no drawback for the 7109 MAC. 161 */ 162 static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg) 163 { 164 struct net_device *ndev = bus->priv; 165 struct stmmac_priv *priv = netdev_priv(ndev); 166 unsigned int mii_address = priv->hw->mii.addr; 167 unsigned int mii_data = priv->hw->mii.data; 168 u32 v; 169 int data; 170 u32 value = MII_BUSY; 171 172 value |= (phyaddr << priv->hw->mii.addr_shift) 173 & priv->hw->mii.addr_mask; 174 value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask; 175 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift) 176 & priv->hw->mii.clk_csr_mask; 177 if (priv->plat->has_gmac4) 178 value |= MII_GMAC4_READ; 179 180 if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY), 181 100, 10000)) 182 return -EBUSY; 183 184 writel(value, priv->ioaddr + mii_address); 185 186 if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY), 187 100, 10000)) 188 return -EBUSY; 189 190 /* Read the data from the MII data register */ 191 data = (int)readl(priv->ioaddr + mii_data); 192 193 return data; 194 } 195 196 /** 197 * stmmac_mdio_write 198 * @bus: points to the mii_bus structure 199 * @phyaddr: MII addr 200 * @phyreg: MII reg 201 * @phydata: phy data 202 * Description: it writes the data into the MII register from within the device. 203 */ 204 static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg, 205 u16 phydata) 206 { 207 struct net_device *ndev = bus->priv; 208 struct stmmac_priv *priv = netdev_priv(ndev); 209 unsigned int mii_address = priv->hw->mii.addr; 210 unsigned int mii_data = priv->hw->mii.data; 211 u32 v; 212 u32 value = MII_BUSY; 213 214 value |= (phyaddr << priv->hw->mii.addr_shift) 215 & priv->hw->mii.addr_mask; 216 value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask; 217 218 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift) 219 & priv->hw->mii.clk_csr_mask; 220 if (priv->plat->has_gmac4) 221 value |= MII_GMAC4_WRITE; 222 else 223 value |= MII_WRITE; 224 225 /* Wait until any existing MII operation is complete */ 226 if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY), 227 100, 10000)) 228 return -EBUSY; 229 230 /* Set the MII address register to write */ 231 writel(phydata, priv->ioaddr + mii_data); 232 writel(value, priv->ioaddr + mii_address); 233 234 /* Wait until any existing MII operation is complete */ 235 return readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY), 236 100, 10000); 237 } 238 239 /** 240 * stmmac_mdio_reset 241 * @bus: points to the mii_bus structure 242 * Description: reset the MII bus 243 */ 244 int stmmac_mdio_reset(struct mii_bus *bus) 245 { 246 #if IS_ENABLED(CONFIG_STMMAC_PLATFORM) 247 struct net_device *ndev = bus->priv; 248 struct stmmac_priv *priv = netdev_priv(ndev); 249 unsigned int mii_address = priv->hw->mii.addr; 250 struct stmmac_mdio_bus_data *data = priv->plat->mdio_bus_data; 251 252 #ifdef CONFIG_OF 253 if (priv->device->of_node) { 254 if (data->reset_gpio < 0) { 255 struct device_node *np = priv->device->of_node; 256 257 if (!np) 258 return 0; 259 260 data->reset_gpio = of_get_named_gpio(np, 261 "snps,reset-gpio", 0); 262 if (data->reset_gpio < 0) 263 return 0; 264 265 data->active_low = of_property_read_bool(np, 266 "snps,reset-active-low"); 267 of_property_read_u32_array(np, 268 "snps,reset-delays-us", data->delays, 3); 269 270 if (devm_gpio_request(priv->device, data->reset_gpio, 271 "mdio-reset")) 272 return 0; 273 } 274 275 gpio_direction_output(data->reset_gpio, 276 data->active_low ? 1 : 0); 277 if (data->delays[0]) 278 msleep(DIV_ROUND_UP(data->delays[0], 1000)); 279 280 gpio_set_value(data->reset_gpio, data->active_low ? 0 : 1); 281 if (data->delays[1]) 282 msleep(DIV_ROUND_UP(data->delays[1], 1000)); 283 284 gpio_set_value(data->reset_gpio, data->active_low ? 1 : 0); 285 if (data->delays[2]) 286 msleep(DIV_ROUND_UP(data->delays[2], 1000)); 287 } 288 #endif 289 290 if (data->phy_reset) { 291 netdev_dbg(ndev, "stmmac_mdio_reset: calling phy_reset\n"); 292 data->phy_reset(priv->plat->bsp_priv); 293 } 294 295 /* This is a workaround for problems with the STE101P PHY. 296 * It doesn't complete its reset until at least one clock cycle 297 * on MDC, so perform a dummy mdio read. To be updated for GMAC4 298 * if needed. 299 */ 300 if (!priv->plat->has_gmac4) 301 writel(0, priv->ioaddr + mii_address); 302 #endif 303 return 0; 304 } 305 306 /** 307 * stmmac_mdio_register 308 * @ndev: net device structure 309 * Description: it registers the MII bus 310 */ 311 int stmmac_mdio_register(struct net_device *ndev) 312 { 313 int err = 0; 314 struct mii_bus *new_bus; 315 struct stmmac_priv *priv = netdev_priv(ndev); 316 struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data; 317 struct device_node *mdio_node = priv->plat->mdio_node; 318 struct device *dev = ndev->dev.parent; 319 int addr, found, max_addr; 320 321 if (!mdio_bus_data) 322 return 0; 323 324 new_bus = mdiobus_alloc(); 325 if (!new_bus) 326 return -ENOMEM; 327 328 if (mdio_bus_data->irqs) 329 memcpy(new_bus->irq, mdio_bus_data->irqs, sizeof(new_bus->irq)); 330 331 #ifdef CONFIG_OF 332 if (priv->device->of_node) 333 mdio_bus_data->reset_gpio = -1; 334 #endif 335 336 new_bus->name = "stmmac"; 337 338 if (priv->plat->has_xgmac) { 339 new_bus->read = &stmmac_xgmac2_mdio_read; 340 new_bus->write = &stmmac_xgmac2_mdio_write; 341 342 /* Right now only C22 phys are supported */ 343 max_addr = MII_XGMAC_MAX_C22ADDR + 1; 344 345 /* Check if DT specified an unsupported phy addr */ 346 if (priv->plat->phy_addr > MII_XGMAC_MAX_C22ADDR) 347 dev_err(dev, "Unsupported phy_addr (max=%d)\n", 348 MII_XGMAC_MAX_C22ADDR); 349 } else { 350 new_bus->read = &stmmac_mdio_read; 351 new_bus->write = &stmmac_mdio_write; 352 max_addr = PHY_MAX_ADDR; 353 } 354 355 new_bus->reset = &stmmac_mdio_reset; 356 snprintf(new_bus->id, MII_BUS_ID_SIZE, "%s-%x", 357 new_bus->name, priv->plat->bus_id); 358 new_bus->priv = ndev; 359 new_bus->phy_mask = mdio_bus_data->phy_mask; 360 new_bus->parent = priv->device; 361 362 err = of_mdiobus_register(new_bus, mdio_node); 363 if (err != 0) { 364 dev_err(dev, "Cannot register the MDIO bus\n"); 365 goto bus_register_fail; 366 } 367 368 if (priv->plat->phy_node || mdio_node) 369 goto bus_register_done; 370 371 found = 0; 372 for (addr = 0; addr < max_addr; addr++) { 373 struct phy_device *phydev = mdiobus_get_phy(new_bus, addr); 374 375 if (!phydev) 376 continue; 377 378 /* 379 * If an IRQ was provided to be assigned after 380 * the bus probe, do it here. 381 */ 382 if (!mdio_bus_data->irqs && 383 (mdio_bus_data->probed_phy_irq > 0)) { 384 new_bus->irq[addr] = mdio_bus_data->probed_phy_irq; 385 phydev->irq = mdio_bus_data->probed_phy_irq; 386 } 387 388 /* 389 * If we're going to bind the MAC to this PHY bus, 390 * and no PHY number was provided to the MAC, 391 * use the one probed here. 392 */ 393 if (priv->plat->phy_addr == -1) 394 priv->plat->phy_addr = addr; 395 396 phy_attached_info(phydev); 397 found = 1; 398 } 399 400 if (!found && !mdio_node) { 401 dev_warn(dev, "No PHY found\n"); 402 mdiobus_unregister(new_bus); 403 mdiobus_free(new_bus); 404 return -ENODEV; 405 } 406 407 bus_register_done: 408 priv->mii = new_bus; 409 410 return 0; 411 412 bus_register_fail: 413 mdiobus_free(new_bus); 414 return err; 415 } 416 417 /** 418 * stmmac_mdio_unregister 419 * @ndev: net device structure 420 * Description: it unregisters the MII bus 421 */ 422 int stmmac_mdio_unregister(struct net_device *ndev) 423 { 424 struct stmmac_priv *priv = netdev_priv(ndev); 425 426 if (!priv->mii) 427 return 0; 428 429 mdiobus_unregister(priv->mii); 430 priv->mii->priv = NULL; 431 mdiobus_free(priv->mii); 432 priv->mii = NULL; 433 434 return 0; 435 } 436