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 <asm/ocp.h>
  36 #include <linux/crc32.h>
  37 #include <linux/mii.h>
  38 #include <linux/phy.h>
  39 #include <linux/fsl_devices.h>
  40
  41 #include <asm/of_platform.h>
  42 #include <asm/io.h>
  43 #include <asm/irq.h>
  44 #include <asm/uaccess.h>
  45 #include <asm/ucc.h>
  46
  47 #include "ucc_geth_mii.h"
  48 #include "ucc_geth.h"
  49
  50 #define DEBUG
  51 #ifdef DEBUG
  52 #define vdbg(format, arg...) printk(KERN_DEBUG , format "\n" , ## arg)
  53 #else
  54 #define vdbg(format, arg...) do {} while(0)
  55 #endif
  56
  57 #define MII_DRV_DESC "QE UCC Ethernet Controller MII Bus"
  58 #define MII_DRV_NAME "fsl-uec_mdio"
  59
  60 /* Write value to the PHY for this device to the register at regnum, */
  61 /* waiting until the write is done before it returns.  All PHY */
  62 /* configuration has to be done through the master UEC MIIM regs */
  63 int uec_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
  64 {
  65         struct ucc_mii_mng __iomem *regs = (void __iomem *)bus->priv;
  66
  67         /* Setting up the MII Mangement Address Register */
  68         out_be32(&regs->miimadd,
  69                  (mii_id << MIIMADD_PHY_ADDRESS_SHIFT) | regnum);
  70
  71         /* Setting up the MII Mangement Control Register with the value */
  72         out_be32(&regs->miimcon, value);
  73
  74         /* Wait till MII management write is complete */
  75         while ((in_be32(&regs->miimind)) & MIIMIND_BUSY)
  76                 cpu_relax();
  77
  78         return 0;
  79 }
  80
  81 /* Reads from register regnum in the PHY for device dev, */
  82 /* returning the value.  Clears miimcom first.  All PHY */
  83 /* configuration has to be done through the TSEC1 MIIM regs */
  84 int uec_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
  85 {
  86         struct ucc_mii_mng __iomem *regs = (void __iomem *)bus->priv;
  87         u16 value;
  88
  89         /* Setting up the MII Mangement Address Register */
  90         out_be32(&regs->miimadd,
  91                  (mii_id << MIIMADD_PHY_ADDRESS_SHIFT) | regnum);
  92
  93         /* Clear miimcom, perform an MII management read cycle */
  94         out_be32(&regs->miimcom, 0);
  95         out_be32(&regs->miimcom, MIIMCOM_READ_CYCLE);
  96
  97         /* Wait till MII management write is complete */
  98         while ((in_be32(&regs->miimind)) & (MIIMIND_BUSY | MIIMIND_NOT_VALID))
  99                 cpu_relax();
 100
 101         /* Read MII management status  */
 102         value = in_be32(&regs->miimstat);
 103
 104         return value;
 105 }
 106
 107 /* Reset the MIIM registers, and wait for the bus to free */
 108 int uec_mdio_reset(struct mii_bus *bus)
 109 {
 110         struct ucc_mii_mng __iomem *regs = (void __iomem *)bus->priv;
 111         unsigned int timeout = PHY_INIT_TIMEOUT;
 112
 113         spin_lock_bh(&bus->mdio_lock);
 114
 115         /* Reset the management interface */
 116         out_be32(&regs->miimcfg, MIIMCFG_RESET_MANAGEMENT);
 117
 118         /* Setup the MII Mgmt clock speed */
 119         out_be32(&regs->miimcfg, MIIMCFG_MANAGEMENT_CLOCK_DIVIDE_BY_112);
 120
 121         /* Wait until the bus is free */
 122         while ((in_be32(&regs->miimind) & MIIMIND_BUSY) && timeout--)
 123                 cpu_relax();
 124
 125         spin_unlock_bh(&bus->mdio_lock);
 126
 127         if (timeout <= 0) {
 128                 printk(KERN_ERR "%s: The MII Bus is stuck!\n", bus->name);
 129                 return -EBUSY;
 130         }
 131
 132         return 0;
 133 }
 134
 135 static int uec_mdio_probe(struct of_device *ofdev, const struct of_device_id *match)
 136 {
 137         struct device *device = &ofdev->dev;
 138         struct device_node *np = ofdev->node, *tempnp = NULL;
 139         struct device_node *child = NULL;
 140         struct ucc_mii_mng __iomem *regs;
 141         struct mii_bus *new_bus;
 142         struct resource res;
 143         int k, err = 0;
 144
 145         new_bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
 146
 147         if (NULL == new_bus)
 148                 return -ENOMEM;
 149
 150         new_bus->name = "UCC Ethernet Controller MII Bus";
 151         new_bus->read = &uec_mdio_read;
 152         new_bus->write = &uec_mdio_write;
 153         new_bus->reset = &uec_mdio_reset;
 154
 155         memset(&res, 0, sizeof(res));
 156
 157         err = of_address_to_resource(np, 0, &res);
 158         if (err)
 159                 goto reg_map_fail;
 160
 161         new_bus->id = res.start;
 162
 163         new_bus->irq = kmalloc(32 * sizeof(int), GFP_KERNEL);
 164
 165         if (NULL == new_bus->irq) {
 166                 err = -ENOMEM;
 167                 goto reg_map_fail;
 168         }
 169
 170         for (k = 0; k < 32; k++)
 171                 new_bus->irq[k] = PHY_POLL;
 172
 173         while ((child = of_get_next_child(np, child)) != NULL) {
 174                 int irq = irq_of_parse_and_map(child, 0);
 175                 if (irq != NO_IRQ) {
 176                         const u32 *id = of_get_property(child, "reg", NULL);
 177                         new_bus->irq[*id] = irq;
 178                 }
 179         }
 180
 181         /* Set the base address */
 182         regs = ioremap(res.start, sizeof(struct ucc_mii_mng));
 183
 184         if (NULL == regs) {
 185                 err = -ENOMEM;
 186                 goto ioremap_fail;
 187         }
 188
 189         new_bus->priv = (void __force *)regs;
 190
 191         new_bus->dev = device;
 192         dev_set_drvdata(device, new_bus);
 193
 194         /* Read MII management master from device tree */
 195         while ((tempnp = of_find_compatible_node(tempnp, "network", "ucc_geth"))
 196                != NULL) {
 197                 struct resource tempres;
 198
 199                 err = of_address_to_resource(tempnp, 0, &tempres);
 200                 if (err)
 201                         goto bus_register_fail;
 202
 203                 /* if our mdio regs fall within this UCC regs range */
 204                 if ((res.start >= tempres.start) &&
 205                     (res.end <= tempres.end)) {
 206                         /* set this UCC to be the MII master */
 207                         const u32 *id = of_get_property(tempnp, "device-id", NULL);
 208                         if (id == NULL)
 209                                 goto bus_register_fail;
 210
 211                         ucc_set_qe_mux_mii_mng(*id - 1);
 212
 213                         /* assign the TBI an address which won't
 214                          * conflict with the PHYs */
 215                         out_be32(&regs->utbipar, UTBIPAR_INIT_TBIPA);
 216                         break;
 217                 }
 218         }
 219
 220         err = mdiobus_register(new_bus);
 221         if (0 != err) {
 222                 printk(KERN_ERR "%s: Cannot register as MDIO bus\n",
 223                        new_bus->name);
 224                 goto bus_register_fail;
 225         }
 226
 227         return 0;
 228
 229 bus_register_fail:
 230         iounmap(regs);
 231 ioremap_fail:
 232         kfree(new_bus->irq);
 233 reg_map_fail:
 234         kfree(new_bus);
 235
 236         return err;
 237 }
 238
 239 int uec_mdio_remove(struct of_device *ofdev)
 240 {
 241         struct device *device = &ofdev->dev;
 242         struct mii_bus *bus = dev_get_drvdata(device);
 243
 244         mdiobus_unregister(bus);
 245
 246         dev_set_drvdata(device, NULL);
 247
 248         iounmap((void __iomem *)bus->priv);
 249         bus->priv = NULL;
 250         kfree(bus);
 251
 252         return 0;
 253 }
 254
 255 static struct of_device_id uec_mdio_match[] = {
 256         {
 257                 .type = "mdio",
 258                 .compatible = "ucc_geth_phy",
 259         },
 260         {},
 261 };
 262
 263 static struct of_platform_driver uec_mdio_driver = {
 264         .name   = MII_DRV_NAME,
 265         .probe  = uec_mdio_probe,
 266         .remove = uec_mdio_remove,
 267         .match_table    = uec_mdio_match,
 268 };
 269
 270 int __init uec_mdio_init(void)
 271 {
 272         return of_register_platform_driver(&uec_mdio_driver);
 273 }
 274
 275 /* called from __init ucc_geth_init, therefore can not be __exit */
 276 void uec_mdio_exit(void)
 277 {
 278         of_unregister_platform_driver(&uec_mdio_driver);
 279 }