LXR linux/drivers/net/ibm

   1/*
   2 * drivers/net/ibm_newemac/tah.c
   3 *
   4 * Driver for PowerPC 4xx on-chip ethernet controller, TAH support.
   5 *
   6 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
   7 *                <benh@kernel.crashing.org>
   8 *
   9 * Based on the arch/ppc version of the driver:
  10 *
  11 * Copyright 2004 MontaVista Software, Inc.
  12 * Matt Porter <mporter@kernel.crashing.org>
  13 *
  14 * Copyright (c) 2005 Eugene Surovegin <ebs@ebshome.net>
  15 *
  16 * This program is free software; you can redistribute  it and/or modify it
  17 * under  the terms of  the GNU General  Public License as published by the
  18 * Free Software Foundation;  either version 2 of the  License, or (at your
  19 * option) any later version.
  20 */
  21#include <asm/io.h>
  22
  23#include "emac.h"
  24#include "core.h"
  25
  26int __devinit tah_attach(struct of_device *ofdev, int channel)
  27{
  28        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
  29
  30        mutex_lock(&dev->lock);
  31        /* Reset has been done at probe() time... nothing else to do for now */
  32        ++dev->users;
  33        mutex_unlock(&dev->lock);
  34
  35        return 0;
  36}
  37
  38void tah_detach(struct of_device *ofdev, int channel)
  39{
  40        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
  41
  42        mutex_lock(&dev->lock);
  43        --dev->users;
  44        mutex_unlock(&dev->lock);
  45}
  46
  47void tah_reset(struct of_device *ofdev)
  48{
  49        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
  50        struct tah_regs __iomem *p = dev->base;
  51        int n;
  52
  53        /* Reset TAH */
  54        out_be32(&p->mr, TAH_MR_SR);
  55        n = 100;
  56        while ((in_be32(&p->mr) & TAH_MR_SR) && n)
  57                --n;
  58
  59        if (unlikely(!n))
  60                printk(KERN_ERR "%s: reset timeout\n", ofdev->node->full_name);
  61
  62        /* 10KB TAH TX FIFO accomodates the max MTU of 9000 */
  63        out_be32(&p->mr,
  64                 TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP |
  65                 TAH_MR_DIG);
  66}
  67
  68int tah_get_regs_len(struct of_device *ofdev)
  69{
  70        return sizeof(struct emac_ethtool_regs_subhdr) +
  71                sizeof(struct tah_regs);
  72}
  73
  74void *tah_dump_regs(struct of_device *ofdev, void *buf)
  75{
  76        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
  77        struct emac_ethtool_regs_subhdr *hdr = buf;
  78        struct tah_regs *regs = (struct tah_regs *)(hdr + 1);
  79
  80        hdr->version = 0;
  81        hdr->index = 0; /* for now, are there chips with more than one
  82                         * zmii ? if yes, then we'll add a cell_index
  83                         * like we do for emac
  84                         */
  85        memcpy_fromio(regs, dev->base, sizeof(struct tah_regs));
  86        return regs + 1;
  87}
  88
  89static int __devinit tah_probe(struct of_device *ofdev,
  90                               const struct of_device_id *match)
  91{
  92        struct device_node *np = ofdev->node;
  93        struct tah_instance *dev;
  94        struct resource regs;
  95        int rc;
  96
  97        rc = -ENOMEM;
  98        dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL);
  99        if (dev == NULL) {
 100                printk(KERN_ERR "%s: could not allocate TAH device!\n",
 101                       np->full_name);
 102                goto err_gone;
 103        }
 104
 105        mutex_init(&dev->lock);
 106        dev->ofdev = ofdev;
 107
 108        rc = -ENXIO;
 109        if (of_address_to_resource(np, 0, &regs)) {
 110                printk(KERN_ERR "%s: Can't get registers address\n",
 111                       np->full_name);
 112                goto err_free;
 113        }
 114
 115        rc = -ENOMEM;
 116        dev->base = (struct tah_regs __iomem *)ioremap(regs.start,
 117                                               sizeof(struct tah_regs));
 118        if (dev->base == NULL) {
 119                printk(KERN_ERR "%s: Can't map device registers!\n",
 120                       np->full_name);
 121                goto err_free;
 122        }
 123
 124        dev_set_drvdata(&ofdev->dev, dev);
 125
 126        /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */
 127        tah_reset(ofdev);
 128
 129        printk(KERN_INFO
 130               "TAH %s initialized\n", ofdev->node->full_name);
 131        wmb();
 132
 133        return 0;
 134
 135 err_free:
 136        kfree(dev);
 137 err_gone:
 138        return rc;
 139}
 140
 141static int __devexit tah_remove(struct of_device *ofdev)
 142{
 143        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
 144
 145        dev_set_drvdata(&ofdev->dev, NULL);
 146
 147        WARN_ON(dev->users != 0);
 148
 149        iounmap(dev->base);
 150        kfree(dev);
 151
 152        return 0;
 153}
 154
 155static struct of_device_id tah_match[] =
 156{
 157        {
 158                .compatible     = "ibm,tah",
 159        },
 160        /* For backward compat with old DT */
 161        {
 162                .type           = "tah",
 163        },
 164        {},
 165};
 166
 167static struct of_platform_driver tah_driver = {
 168        .name = "emac-tah",
 169        .match_table = tah_match,
 170
 171        .probe = tah_probe,
 172        .remove = tah_remove,
 173};
 174
 175int __init tah_init(void)
 176{
 177        return of_register_platform_driver(&tah_driver);
 178}
 179
 180void tah_exit(void)
 181{
 182        of_unregister_platform_driver(&tah_driver);
 183}
 184