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 You should have received a copy of the GNU General Public License along with 17 this program; if not, write to the Free Software Foundation, Inc., 18 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 19 20 The full GNU General Public License is included in this distribution in 21 the file called "COPYING". 22 23 Author: Carl Shaw <carl.shaw@st.com> 24 Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com> 25 *******************************************************************************/ 26 27 #include <linux/mii.h> 28 #include <linux/phy.h> 29 #include <linux/slab.h> 30 #include <asm/io.h> 31 32 #include "stmmac.h" 33 34 #define MII_BUSY 0x00000001 35 #define MII_WRITE 0x00000002 36 37 static int stmmac_mdio_busy_wait(void __iomem *ioaddr, unsigned int mii_addr) 38 { 39 unsigned long curr; 40 unsigned long finish = jiffies + 3 * HZ; 41 42 do { 43 curr = jiffies; 44 if (readl(ioaddr + mii_addr) & MII_BUSY) 45 cpu_relax(); 46 else 47 return 0; 48 } while (!time_after_eq(curr, finish)); 49 50 return -EBUSY; 51 } 52 53 /** 54 * stmmac_mdio_read 55 * @bus: points to the mii_bus structure 56 * @phyaddr: MII addr reg bits 15-11 57 * @phyreg: MII addr reg bits 10-6 58 * Description: it reads data from the MII register from within the phy device. 59 * For the 7111 GMAC, we must set the bit 0 in the MII address register while 60 * accessing the PHY registers. 61 * Fortunately, it seems this has no drawback for the 7109 MAC. 62 */ 63 static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg) 64 { 65 struct net_device *ndev = bus->priv; 66 struct stmmac_priv *priv = netdev_priv(ndev); 67 unsigned int mii_address = priv->hw->mii.addr; 68 unsigned int mii_data = priv->hw->mii.data; 69 70 int data; 71 u16 regValue = (((phyaddr << 11) & (0x0000F800)) | 72 ((phyreg << 6) & (0x000007C0))); 73 regValue |= MII_BUSY | ((priv->clk_csr & 0xF) << 2); 74 75 if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address)) 76 return -EBUSY; 77 78 writel(regValue, priv->ioaddr + mii_address); 79 80 if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address)) 81 return -EBUSY; 82 83 /* Read the data from the MII data register */ 84 data = (int)readl(priv->ioaddr + mii_data); 85 86 return data; 87 } 88 89 /** 90 * stmmac_mdio_write 91 * @bus: points to the mii_bus structure 92 * @phyaddr: MII addr reg bits 15-11 93 * @phyreg: MII addr reg bits 10-6 94 * @phydata: phy data 95 * Description: it writes the data into the MII register from within the device. 96 */ 97 static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg, 98 u16 phydata) 99 { 100 struct net_device *ndev = bus->priv; 101 struct stmmac_priv *priv = netdev_priv(ndev); 102 unsigned int mii_address = priv->hw->mii.addr; 103 unsigned int mii_data = priv->hw->mii.data; 104 105 u16 value = 106 (((phyaddr << 11) & (0x0000F800)) | ((phyreg << 6) & (0x000007C0))) 107 | MII_WRITE; 108 109 value |= MII_BUSY | ((priv->clk_csr & 0xF) << 2); 110 111 /* Wait until any existing MII operation is complete */ 112 if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address)) 113 return -EBUSY; 114 115 /* Set the MII address register to write */ 116 writel(phydata, priv->ioaddr + mii_data); 117 writel(value, priv->ioaddr + mii_address); 118 119 /* Wait until any existing MII operation is complete */ 120 return stmmac_mdio_busy_wait(priv->ioaddr, mii_address); 121 } 122 123 /** 124 * stmmac_mdio_reset 125 * @bus: points to the mii_bus structure 126 * Description: reset the MII bus 127 */ 128 static int stmmac_mdio_reset(struct mii_bus *bus) 129 { 130 #if defined(CONFIG_STMMAC_PLATFORM) 131 struct net_device *ndev = bus->priv; 132 struct stmmac_priv *priv = netdev_priv(ndev); 133 unsigned int mii_address = priv->hw->mii.addr; 134 135 if (priv->plat->mdio_bus_data->phy_reset) { 136 pr_debug("stmmac_mdio_reset: calling phy_reset\n"); 137 priv->plat->mdio_bus_data->phy_reset(priv->plat->bsp_priv); 138 } 139 140 /* This is a workaround for problems with the STE101P PHY. 141 * It doesn't complete its reset until at least one clock cycle 142 * on MDC, so perform a dummy mdio read. 143 */ 144 writel(0, priv->ioaddr + mii_address); 145 #endif 146 return 0; 147 } 148 149 /** 150 * stmmac_mdio_register 151 * @ndev: net device structure 152 * Description: it registers the MII bus 153 */ 154 int stmmac_mdio_register(struct net_device *ndev) 155 { 156 int err = 0; 157 struct mii_bus *new_bus; 158 int *irqlist; 159 struct stmmac_priv *priv = netdev_priv(ndev); 160 struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data; 161 int addr, found; 162 163 if (!mdio_bus_data) 164 return 0; 165 166 new_bus = mdiobus_alloc(); 167 if (new_bus == NULL) 168 return -ENOMEM; 169 170 if (mdio_bus_data->irqs) 171 irqlist = mdio_bus_data->irqs; 172 else 173 irqlist = priv->mii_irq; 174 175 new_bus->name = "stmmac"; 176 new_bus->read = &stmmac_mdio_read; 177 new_bus->write = &stmmac_mdio_write; 178 new_bus->reset = &stmmac_mdio_reset; 179 snprintf(new_bus->id, MII_BUS_ID_SIZE, "%s-%x", 180 new_bus->name, priv->plat->bus_id); 181 new_bus->priv = ndev; 182 new_bus->irq = irqlist; 183 new_bus->phy_mask = mdio_bus_data->phy_mask; 184 new_bus->parent = priv->device; 185 err = mdiobus_register(new_bus); 186 if (err != 0) { 187 pr_err("%s: Cannot register as MDIO bus\n", new_bus->name); 188 goto bus_register_fail; 189 } 190 191 found = 0; 192 for (addr = 0; addr < PHY_MAX_ADDR; addr++) { 193 struct phy_device *phydev = new_bus->phy_map[addr]; 194 if (phydev) { 195 int act = 0; 196 char irq_num[4]; 197 char *irq_str; 198 199 /* 200 * If an IRQ was provided to be assigned after 201 * the bus probe, do it here. 202 */ 203 if ((mdio_bus_data->irqs == NULL) && 204 (mdio_bus_data->probed_phy_irq > 0)) { 205 irqlist[addr] = mdio_bus_data->probed_phy_irq; 206 phydev->irq = mdio_bus_data->probed_phy_irq; 207 } 208 209 /* 210 * If we're going to bind the MAC to this PHY bus, 211 * and no PHY number was provided to the MAC, 212 * use the one probed here. 213 */ 214 if (priv->plat->phy_addr == -1) 215 priv->plat->phy_addr = addr; 216 217 act = (priv->plat->phy_addr == addr); 218 switch (phydev->irq) { 219 case PHY_POLL: 220 irq_str = "POLL"; 221 break; 222 case PHY_IGNORE_INTERRUPT: 223 irq_str = "IGNORE"; 224 break; 225 default: 226 sprintf(irq_num, "%d", phydev->irq); 227 irq_str = irq_num; 228 break; 229 } 230 pr_info("%s: PHY ID %08x at %d IRQ %s (%s)%s\n", 231 ndev->name, phydev->phy_id, addr, 232 irq_str, dev_name(&phydev->dev), 233 act ? " active" : ""); 234 found = 1; 235 } 236 } 237 238 if (!found) { 239 pr_warning("%s: No PHY found\n", ndev->name); 240 mdiobus_unregister(new_bus); 241 mdiobus_free(new_bus); 242 return -ENODEV; 243 } 244 245 priv->mii = new_bus; 246 247 return 0; 248 249 bus_register_fail: 250 mdiobus_free(new_bus); 251 return err; 252 } 253 254 /** 255 * stmmac_mdio_unregister 256 * @ndev: net device structure 257 * Description: it unregisters the MII bus 258 */ 259 int stmmac_mdio_unregister(struct net_device *ndev) 260 { 261 struct stmmac_priv *priv = netdev_priv(ndev); 262 263 if (!priv->mii) 264 return 0; 265 266 mdiobus_unregister(priv->mii); 267 priv->mii->priv = NULL; 268 mdiobus_free(priv->mii); 269 priv->mii = NULL; 270 271 return 0; 272 } 273