drivers/net/ucc_geth_mii.c

   1 /*
   2  * drivers/net/ucc_geth_mii.c
   3  *
   4  * QE UCC Gigabit Ethernet Driver -- MII Management Bus Implementation
   5  * Provides Bus interface for MII Management regs in the UCC register space
   6  *
   7  * Copyright (C) 2007 Freescale Semiconductor, Inc.
   8  *
   9  * Authors: Li Yang <leoli@freescale.com>
  10  *          Kim Phillips <kim.phillips@freescale.com>
  11  *
  12  * This program is free software; you can redistribute  it and/or modify it
  13  * under  the terms of  the GNU General  Public License as published by the
  14  * Free Software Foundation;  either version 2 of the  License, or (at your
  15  * option) any later version.
  16  *
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/sched.h>
  21 #include <linux/string.h>
  22 #include <linux/errno.h>
  23 #include <linux/unistd.h>
  24 #include <linux/slab.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/init.h>
  27 #include <linux/delay.h>
  28 #include <linux/netdevice.h>
  29 #include <linux/etherdevice.h>
  30 #include <linux/skbuff.h>
  31 #include <linux/spinlock.h>
  32 #include <linux/mm.h>
  33 #include <linux/module.h>
  34 #include <linux/platform_device.h>
  35 #include <linux/crc32.h>
  36 #include <linux/mii.h>
  37 #include <linux/phy.h>
  38 #include <linux/fsl_devices.h>
  39 #include <linux/of_platform.h>
  40
  41 #include <asm/io.h>
  42 #include <asm/irq.h>
  43 #include <asm/uaccess.h>
  44 #include <asm/ucc.h>
  45
  46 #include "ucc_geth_mii.h"
  47 #include "ucc_geth.h"
  48
  49 #define DEBUG
  50 #ifdef DEBUG
  51 #define vdbg(format, arg...) printk(KERN_DEBUG , format "\n" , ## arg)
  52 #else
  53 #define vdbg(format, arg...) do {} while(0)
  54 #endif
  55
  56 #define MII_DRV_DESC "QE UCC Ethernet Controller MII Bus"
  57 #define MII_DRV_NAME "fsl-uec_mdio"
  58
  59 /* Write value to the PHY for this device to the register at regnum, */
  60 /* waiting until the write is done before it returns.  All PHY */
  61 /* configuration has to be done through the master UEC MIIM regs */
  62 int uec_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
  63 {
  64         struct ucc_mii_mng __iomem *regs = (void __iomem *)bus->priv;
  65
  66         /* Setting up the MII Mangement Address Register */
  67         out_be32(&regs->miimadd,
  68                  (mii_id << MIIMADD_PHY_ADDRESS_SHIFT) | regnum);
  69
  70         /* Setting up the MII Mangement Control Register with the value */
  71         out_be32(&regs->miimcon, value);
  72
  73         /* Wait till MII management write is complete */
  74         while ((in_be32(&regs->miimind)) & MIIMIND_BUSY)
  75                 cpu_relax();
  76
  77         return 0;
  78 }
  79
  80 /* Reads from register regnum in the PHY for device dev, */
  81 /* returning the value.  Clears miimcom first.  All PHY */
  82 /* configuration has to be done through the TSEC1 MIIM regs */
  83 int uec_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
  84 {
  85         struct ucc_mii_mng __iomem *regs = (void __iomem *)bus->priv;
  86         u16 value;
  87
  88         /* Setting up the MII Mangement Address Register */
  89         out_be32(&regs->miimadd,
  90                  (mii_id << MIIMADD_PHY_ADDRESS_SHIFT) | regnum);
  91
  92         /* Clear miimcom, perform an MII management read cycle */
  93         out_be32(&regs->miimcom, 0);
  94         out_be32(&regs->miimcom, MIIMCOM_READ_CYCLE);
  95
  96         /* Wait till MII management write is complete */
  97         while ((in_be32(&regs->miimind)) & (MIIMIND_BUSY | MIIMIND_NOT_VALID))
  98                 cpu_relax();
  99
 100         /* Read MII management status  */
 101         value = in_be32(&regs->miimstat);
 102
 103         return value;
 104 }
 105
 106 /* Reset the MIIM registers, and wait for the bus to free */
 107 static int uec_mdio_reset(struct mii_bus *bus)
 108 {
 109         struct ucc_mii_mng __iomem *regs = (void __iomem *)bus->priv;
 110         unsigned int timeout = PHY_INIT_TIMEOUT;
 111
 112         mutex_lock(&bus->mdio_lock);
 113
 114         /* Reset the management interface */
 115         out_be32(&regs->miimcfg, MIIMCFG_RESET_MANAGEMENT);
 116
 117         /* Setup the MII Mgmt clock speed */
 118         out_be32(&regs->miimcfg, MIIMCFG_MANAGEMENT_CLOCK_DIVIDE_BY_112);
 119
 120         /* Wait until the bus is free */
 121         while ((in_be32(&regs->miimind) & MIIMIND_BUSY) && timeout--)
 122                 cpu_relax();
 123
 124         mutex_unlock(&bus->mdio_lock);
 125
 126         if (timeout <= 0) {
 127                 printk(KERN_ERR "%s: The MII Bus is stuck!\n", bus->name);
 128                 return -EBUSY;
 129         }
 130
 131         return 0;
 132 }
 133
 134 static int uec_mdio_probe(struct of_device *ofdev, const struct of_device_id *match)
 135 {
 136         struct device *device = &ofdev->dev;
 137         struct device_node *np = ofdev->node, *tempnp = NULL;
 138         struct device_node *child = NULL;
 139         struct ucc_mii_mng __iomem *regs;
 140         struct mii_bus *new_bus;
 141         struct resource res;
 142         int k, err = 0;
 143
 144         new_bus = mdiobus_alloc();
 145         if (NULL == new_bus)
 146                 return -ENOMEM;
 147
 148         new_bus->name = "UCC Ethernet Controller MII Bus";
 149         new_bus->read = &uec_mdio_read;
 150         new_bus->write = &uec_mdio_write;
 151         new_bus->reset = &uec_mdio_reset;
 152
 153         memset(&res, 0, sizeof(res));
 154
 155         err = of_address_to_resource(np, 0, &res);
 156         if (err)
 157                 goto reg_map_fail;
 158
 159         uec_mdio_bus_name(new_bus->id, np);
 160
 161         new_bus->irq = kmalloc(32 * sizeof(int), GFP_KERNEL);
 162
 163         if (NULL == new_bus->irq) {
 164                 err = -ENOMEM;
 165                 goto reg_map_fail;
 166         }
 167
 168         for (k = 0; k < 32; k++)
 169                 new_bus->irq[k] = PHY_POLL;
 170
 171         while ((child = of_get_next_child(np, child)) != NULL) {
 172                 int irq = irq_of_parse_and_map(child, 0);
 173                 if (irq != NO_IRQ) {
 174                         const u32 *id = of_get_property(child, "reg", NULL);
 175                         new_bus->irq[*id] = irq;
 176                 }
 177         }
 178
 179         /* Set the base address */
 180         regs = ioremap(res.start, sizeof(struct ucc_mii_mng));
 181
 182         if (NULL == regs) {
 183                 err = -ENOMEM;
 184                 goto ioremap_fail;
 185         }
 186
 187         new_bus->priv = (void __force *)regs;
 188
 189         new_bus->parent = device;
 190         dev_set_drvdata(device, new_bus);
 191
 192         /* Read MII management master from device tree */
 193         while ((tempnp = of_find_compatible_node(tempnp, "network", "ucc_geth"))
 194                != NULL) {
 195                 struct resource tempres;
 196
 197                 err = of_address_to_resource(tempnp, 0, &tempres);
 198                 if (err)
 199                         goto bus_register_fail;
 200
 201                 /* if our mdio regs fall within this UCC regs range */
 202                 if ((res.start >= tempres.start) &&
 203                     (res.end <= tempres.end)) {
 204                         /* set this UCC to be the MII master */
 205                         const u32 *id;
 206
 207                         id = of_get_property(tempnp, "cell-index", NULL);
 208                         if (!id) {
 209                                 id = of_get_property(tempnp, "device-id", NULL);
 210                                 if (!id)
 211                                         goto bus_register_fail;
 212                         }
 213
 214                         ucc_set_qe_mux_mii_mng(*id - 1);
 215
 216                         /* assign the TBI an address which won't
 217                          * conflict with the PHYs */
 218                         out_be32(&regs->utbipar, UTBIPAR_INIT_TBIPA);
 219                         break;
 220                 }
 221         }
 222
 223         err = mdiobus_register(new_bus);
 224         if (0 != err) {
 225                 printk(KERN_ERR "%s: Cannot register as MDIO bus\n",
 226                        new_bus->name);
 227                 goto bus_register_fail;
 228         }
 229
 230         return 0;
 231
 232 bus_register_fail:
 233         iounmap(regs);
 234 ioremap_fail:
 235         kfree(new_bus->irq);
 236 reg_map_fail:
 237         mdiobus_free(new_bus);
 238
 239         return err;
 240 }
 241
 242 static int uec_mdio_remove(struct of_device *ofdev)
 243 {
 244         struct device *device = &ofdev->dev;
 245         struct mii_bus *bus = dev_get_drvdata(device);
 246
 247         mdiobus_unregister(bus);
 248
 249         dev_set_drvdata(device, NULL);
 250
 251         iounmap((void __iomem *)bus->priv);
 252         bus->priv = NULL;
 253         mdiobus_free(bus);
 254
 255         return 0;
 256 }
 257
 258 static struct of_device_id uec_mdio_match[] = {
 259         {
 260                 .type = "mdio",
 261                 .compatible = "ucc_geth_phy",
 262         },
 263         {
 264                 .compatible = "fsl,ucc-mdio",
 265         },
 266         {},
 267 };
 268
 269 static struct of_platform_driver uec_mdio_driver = {
 270         .name   = MII_DRV_NAME,
 271         .probe  = uec_mdio_probe,
 272         .remove = uec_mdio_remove,
 273         .match_table    = uec_mdio_match,
 274 };
 275
 276 int __init uec_mdio_init(void)
 277 {
 278         return of_register_platform_driver(&uec_mdio_driver);
 279 }
 280
 281 /* called from __init ucc_geth_init, therefore can not be __exit */
 282 void uec_mdio_exit(void)
 283 {
 284         of_unregister_platform_driver(&uec_mdio_driver);
 285 }
 286
 287 void uec_mdio_bus_name(char *name, struct device_node *np)
 288 {
 289         const u32 *reg;
 290
 291         reg = of_get_property(np, "reg", NULL);
 292
 293         snprintf(name, MII_BUS_ID_SIZE, "%s@%x", np->name, reg ? *reg : 0);
 294 }
 295