drivers/net/fsl_pq_mdio.c

   1 /*
   2  * Freescale PowerQUICC Ethernet Driver -- MIIM bus implementation
   3  * Provides Bus interface for MIIM regs
   4  *
   5  * Author: Andy Fleming <afleming@freescale.com>
   6  *
   7  * Copyright (c) 2002-2004,2008 Freescale Semiconductor, Inc.
   8  *
   9  * Based on gianfar_mii.c and ucc_geth_mii.c (Li Yang, Kim Phillips)
  10  *
  11  * This program is free software; you can redistribute  it and/or modify it
  12  * under  the terms of  the GNU General  Public License as published by the
  13  * Free Software Foundation;  either version 2 of the  License, or (at your
  14  * option) any later version.
  15  *
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/string.h>
  20 #include <linux/errno.h>
  21 #include <linux/unistd.h>
  22 #include <linux/slab.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/init.h>
  25 #include <linux/delay.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/mm.h>
  31 #include <linux/module.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/crc32.h>
  34 #include <linux/mii.h>
  35 #include <linux/phy.h>
  36 #include <linux/of.h>
  37 #include <linux/of_mdio.h>
  38 #include <linux/of_platform.h>
  39
  40 #include <asm/io.h>
  41 #include <asm/irq.h>
  42 #include <asm/uaccess.h>
  43 #include <asm/ucc.h>
  44
  45 #include "gianfar.h"
  46 #include "fsl_pq_mdio.h"
  47
  48 /*
  49  * Write value to the PHY at mii_id at register regnum,
  50  * on the bus attached to the local interface, which may be different from the
  51  * generic mdio bus (tied to a single interface), waiting until the write is
  52  * done before returning. This is helpful in programming interfaces like
  53  * the TBI which control interfaces like onchip SERDES and are always tied to
  54  * the local mdio pins, which may not be the same as system mdio bus, used for
  55  * controlling the external PHYs, for example.
  56  */
  57 int fsl_pq_local_mdio_write(struct fsl_pq_mdio __iomem *regs, int mii_id,
  58                 int regnum, u16 value)
  59 {
  60         /* Set the PHY address and the register address we want to write */
  61         out_be32(&regs->miimadd, (mii_id << 8) | regnum);
  62
  63         /* Write out the value we want */
  64         out_be32(&regs->miimcon, value);
  65
  66         /* Wait for the transaction to finish */
  67         while (in_be32(&regs->miimind) & MIIMIND_BUSY)
  68                 cpu_relax();
  69
  70         return 0;
  71 }
  72
  73 /*
  74  * Read the bus for PHY at addr mii_id, register regnum, and
  75  * return the value.  Clears miimcom first.  All PHY operation
  76  * done on the bus attached to the local interface,
  77  * which may be different from the generic mdio bus
  78  * This is helpful in programming interfaces like
  79  * the TBI which, in turn, control interfaces like onchip SERDES
  80  * and are always tied to the local mdio pins, which may not be the
  81  * same as system mdio bus, used for controlling the external PHYs, for eg.
  82  */
  83 int fsl_pq_local_mdio_read(struct fsl_pq_mdio __iomem *regs,
  84                 int mii_id, int regnum)
  85 {
  86         u16 value;
  87
  88         /* Set the PHY address and the register address we want to read */
  89         out_be32(&regs->miimadd, (mii_id << 8) | regnum);
  90
  91         /* Clear miimcom, and then initiate a read */
  92         out_be32(&regs->miimcom, 0);
  93         out_be32(&regs->miimcom, MII_READ_COMMAND);
  94
  95         /* Wait for the transaction to finish */
  96         while (in_be32(&regs->miimind) & (MIIMIND_NOTVALID | MIIMIND_BUSY))
  97                 cpu_relax();
  98
  99         /* Grab the value of the register from miimstat */
 100         value = in_be32(&regs->miimstat);
 101
 102         return value;
 103 }
 104
 105 /*
 106  * Write value to the PHY at mii_id at register regnum,
 107  * on the bus, waiting until the write is done before returning.
 108  */
 109 int fsl_pq_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
 110 {
 111         struct fsl_pq_mdio __iomem *regs = (void __iomem *)bus->priv;
 112
 113         /* Write to the local MII regs */
 114         return(fsl_pq_local_mdio_write(regs, mii_id, regnum, value));
 115 }
 116
 117 /*
 118  * Read the bus for PHY at addr mii_id, register regnum, and
 119  * return the value.  Clears miimcom first.
 120  */
 121 int fsl_pq_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
 122 {
 123         struct fsl_pq_mdio __iomem *regs = (void __iomem *)bus->priv;
 124
 125         /* Read the local MII regs */
 126         return(fsl_pq_local_mdio_read(regs, mii_id, regnum));
 127 }
 128
 129 /* Reset the MIIM registers, and wait for the bus to free */
 130 static int fsl_pq_mdio_reset(struct mii_bus *bus)
 131 {
 132         struct fsl_pq_mdio __iomem *regs = (void __iomem *)bus->priv;
 133         int timeout = PHY_INIT_TIMEOUT;
 134
 135         mutex_lock(&bus->mdio_lock);
 136
 137         /* Reset the management interface */
 138         out_be32(&regs->miimcfg, MIIMCFG_RESET);
 139
 140         /* Setup the MII Mgmt clock speed */
 141         out_be32(&regs->miimcfg, MIIMCFG_INIT_VALUE);
 142
 143         /* Wait until the bus is free */
 144         while ((in_be32(&regs->miimind) & MIIMIND_BUSY) && timeout--)
 145                 cpu_relax();
 146
 147         mutex_unlock(&bus->mdio_lock);
 148
 149         if (timeout < 0) {
 150                 printk(KERN_ERR "%s: The MII Bus is stuck!\n",
 151                                 bus->name);
 152                 return -EBUSY;
 153         }
 154
 155         return 0;
 156 }
 157
 158 void fsl_pq_mdio_bus_name(char *name, struct device_node *np)
 159 {
 160         const u32 *addr;
 161         u64 taddr = OF_BAD_ADDR;
 162
 163         addr = of_get_address(np, 0, NULL, NULL);
 164         if (addr)
 165                 taddr = of_translate_address(np, addr);
 166
 167         snprintf(name, MII_BUS_ID_SIZE, "%s@%llx", np->name,
 168                 (unsigned long long)taddr);
 169 }
 170 EXPORT_SYMBOL_GPL(fsl_pq_mdio_bus_name);
 171
 172 /* Scan the bus in reverse, looking for an empty spot */
 173 static int fsl_pq_mdio_find_free(struct mii_bus *new_bus)
 174 {
 175         int i;
 176
 177         for (i = PHY_MAX_ADDR; i > 0; i--) {
 178                 u32 phy_id;
 179
 180                 if (get_phy_id(new_bus, i, &phy_id))
 181                         return -1;
 182
 183                 if (phy_id == 0xffffffff)
 184                         break;
 185         }
 186
 187         return i;
 188 }
 189
 190
 191 #if defined(CONFIG_GIANFAR) || defined(CONFIG_GIANFAR_MODULE)
 192 static u32 __iomem *get_gfar_tbipa(struct fsl_pq_mdio __iomem *regs)
 193 {
 194         struct gfar __iomem *enet_regs;
 195
 196         /*
 197          * This is mildly evil, but so is our hardware for doing this.
 198          * Also, we have to cast back to struct gfar because of
 199          * definition weirdness done in gianfar.h.
 200          */
 201         enet_regs = (struct gfar __iomem *)
 202                 ((char __iomem *)regs - offsetof(struct gfar, gfar_mii_regs));
 203
 204         return &enet_regs->tbipa;
 205 }
 206 #endif
 207
 208
 209 #if defined(CONFIG_UCC_GETH) || defined(CONFIG_UCC_GETH_MODULE)
 210 static int get_ucc_id_for_range(u64 start, u64 end, u32 *ucc_id)
 211 {
 212         struct device_node *np = NULL;
 213         int err = 0;
 214
 215         for_each_compatible_node(np, NULL, "ucc_geth") {
 216                 struct resource tempres;
 217
 218                 err = of_address_to_resource(np, 0, &tempres);
 219                 if (err)
 220                         continue;
 221
 222                 /* if our mdio regs fall within this UCC regs range */
 223                 if ((start >= tempres.start) && (end <= tempres.end)) {
 224                         /* Find the id of the UCC */
 225                         const u32 *id;
 226
 227                         id = of_get_property(np, "cell-index", NULL);
 228                         if (!id) {
 229                                 id = of_get_property(np, "device-id", NULL);
 230                                 if (!id)
 231                                         continue;
 232                         }
 233
 234                         *ucc_id = *id;
 235
 236                         return 0;
 237                 }
 238         }
 239
 240         if (err)
 241                 return err;
 242         else
 243                 return -EINVAL;
 244 }
 245 #endif
 246
 247
 248 static int fsl_pq_mdio_probe(struct of_device *ofdev,
 249                 const struct of_device_id *match)
 250 {
 251         struct device_node *np = ofdev->node;
 252         struct device_node *tbi;
 253         struct fsl_pq_mdio __iomem *regs;
 254         u32 __iomem *tbipa;
 255         struct mii_bus *new_bus;
 256         int tbiaddr = -1;
 257         u64 addr, size;
 258         int err = 0;
 259
 260         new_bus = mdiobus_alloc();
 261         if (NULL == new_bus)
 262                 return -ENOMEM;
 263
 264         new_bus->name = "Freescale PowerQUICC MII Bus",
 265         new_bus->read = &fsl_pq_mdio_read,
 266         new_bus->write = &fsl_pq_mdio_write,
 267         new_bus->reset = &fsl_pq_mdio_reset,
 268         fsl_pq_mdio_bus_name(new_bus->id, np);
 269
 270         /* Set the PHY base address */
 271         addr = of_translate_address(np, of_get_address(np, 0, &size, NULL));
 272         regs = ioremap(addr, size);
 273
 274         if (NULL == regs) {
 275                 err = -ENOMEM;
 276                 goto err_free_bus;
 277         }
 278
 279         new_bus->priv = (void __force *)regs;
 280
 281         new_bus->irq = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL);
 282
 283         if (NULL == new_bus->irq) {
 284                 err = -ENOMEM;
 285                 goto err_unmap_regs;
 286         }
 287
 288         new_bus->parent = &ofdev->dev;
 289         dev_set_drvdata(&ofdev->dev, new_bus);
 290
 291         if (of_device_is_compatible(np, "fsl,gianfar-mdio") ||
 292                         of_device_is_compatible(np, "fsl,gianfar-tbi") ||
 293                         of_device_is_compatible(np, "gianfar")) {
 294 #if defined(CONFIG_GIANFAR) || defined(CONFIG_GIANFAR_MODULE)
 295                 tbipa = get_gfar_tbipa(regs);
 296 #else
 297                 err = -ENODEV;
 298                 goto err_free_irqs;
 299 #endif
 300         } else if (of_device_is_compatible(np, "fsl,ucc-mdio") ||
 301                         of_device_is_compatible(np, "ucc_geth_phy")) {
 302 #if defined(CONFIG_UCC_GETH) || defined(CONFIG_UCC_GETH_MODULE)
 303                 u32 id;
 304                 static u32 mii_mng_master;
 305
 306                 tbipa = &regs->utbipar;
 307
 308                 if ((err = get_ucc_id_for_range(addr, addr + size, &id)))
 309                         goto err_free_irqs;
 310
 311                 if (!mii_mng_master) {
 312                         mii_mng_master = id;
 313                         ucc_set_qe_mux_mii_mng(id - 1);
 314                 }
 315 #else
 316                 err = -ENODEV;
 317                 goto err_free_irqs;
 318 #endif
 319         } else {
 320                 err = -ENODEV;
 321                 goto err_free_irqs;
 322         }
 323
 324         for_each_child_of_node(np, tbi) {
 325                 if (!strncmp(tbi->type, "tbi-phy", 8))
 326                         break;
 327         }
 328
 329         if (tbi) {
 330                 const u32 *prop = of_get_property(tbi, "reg", NULL);
 331
 332                 if (prop)
 333                         tbiaddr = *prop;
 334         }
 335
 336         if (tbiaddr == -1) {
 337                 out_be32(tbipa, 0);
 338
 339                 tbiaddr = fsl_pq_mdio_find_free(new_bus);
 340         }
 341
 342         /*
 343          * We define TBIPA at 0 to be illegal, opting to fail for boards that
 344          * have PHYs at 1-31, rather than change tbipa and rescan.
 345          */
 346         if (tbiaddr == 0) {
 347                 err = -EBUSY;
 348
 349                 goto err_free_irqs;
 350         }
 351
 352         out_be32(tbipa, tbiaddr);
 353
 354         err = of_mdiobus_register(new_bus, np);
 355         if (err) {
 356                 printk (KERN_ERR "%s: Cannot register as MDIO bus\n",
 357                                 new_bus->name);
 358                 goto err_free_irqs;
 359         }
 360
 361         return 0;
 362
 363 err_free_irqs:
 364         kfree(new_bus->irq);
 365 err_unmap_regs:
 366         iounmap(regs);
 367 err_free_bus:
 368         kfree(new_bus);
 369
 370         return err;
 371 }
 372
 373
 374 static int fsl_pq_mdio_remove(struct of_device *ofdev)
 375 {
 376         struct device *device = &ofdev->dev;
 377         struct mii_bus *bus = dev_get_drvdata(device);
 378
 379         mdiobus_unregister(bus);
 380
 381         dev_set_drvdata(device, NULL);
 382
 383         iounmap((void __iomem *)bus->priv);
 384         bus->priv = NULL;
 385         mdiobus_free(bus);
 386
 387         return 0;
 388 }
 389
 390 static struct of_device_id fsl_pq_mdio_match[] = {
 391         {
 392                 .type = "mdio",
 393                 .compatible = "ucc_geth_phy",
 394         },
 395         {
 396                 .type = "mdio",
 397                 .compatible = "gianfar",
 398         },
 399         {
 400                 .compatible = "fsl,ucc-mdio",
 401         },
 402         {
 403                 .compatible = "fsl,gianfar-tbi",
 404         },
 405         {
 406                 .compatible = "fsl,gianfar-mdio",
 407         },
 408         {},
 409 };
 410 MODULE_DEVICE_TABLE(of, fsl_pq_mdio_match);
 411
 412 static struct of_platform_driver fsl_pq_mdio_driver = {
 413         .name = "fsl-pq_mdio",
 414         .probe = fsl_pq_mdio_probe,
 415         .remove = fsl_pq_mdio_remove,
 416         .match_table = fsl_pq_mdio_match,
 417 };
 418
 419 int __init fsl_pq_mdio_init(void)
 420 {
 421         return of_register_platform_driver(&fsl_pq_mdio_driver);
 422 }
 423 module_init(fsl_pq_mdio_init);
 424
 425 void fsl_pq_mdio_exit(void)
 426 {
 427         of_unregister_platform_driver(&fsl_pq_mdio_driver);
 428 }
 429 module_exit(fsl_pq_mdio_exit);
 430 MODULE_LICENSE("GPL");