LXR linux/drivers/net/ethernet/ibm/emac/tah.c

   1/*
   2 * drivers/net/ethernet/ibm/emac/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 tah_attach(struct platform_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 platform_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 platform_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",
  61                        ofdev->dev.of_node->full_name);
  62
  63        /* 10KB TAH TX FIFO accommodates the max MTU of 9000 */
  64        out_be32(&p->mr,
  65                 TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP |
  66                 TAH_MR_DIG);
  67}
  68
  69int tah_get_regs_len(struct platform_device *ofdev)
  70{
  71        return sizeof(struct emac_ethtool_regs_subhdr) +
  72                sizeof(struct tah_regs);
  73}
  74
  75void *tah_dump_regs(struct platform_device *ofdev, void *buf)
  76{
  77        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
  78        struct emac_ethtool_regs_subhdr *hdr = buf;
  79        struct tah_regs *regs = (struct tah_regs *)(hdr + 1);
  80
  81        hdr->version = 0;
  82        hdr->index = 0; /* for now, are there chips with more than one
  83                         * zmii ? if yes, then we'll add a cell_index
  84                         * like we do for emac
  85                         */
  86        memcpy_fromio(regs, dev->base, sizeof(struct tah_regs));
  87        return regs + 1;
  88}
  89
  90static int tah_probe(struct platform_device *ofdev)
  91{
  92        struct device_node *np = ofdev->dev.of_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                goto err_gone;
 101
 102        mutex_init(&dev->lock);
 103        dev->ofdev = ofdev;
 104
 105        rc = -ENXIO;
 106        if (of_address_to_resource(np, 0, &regs)) {
 107                printk(KERN_ERR "%s: Can't get registers address\n",
 108                       np->full_name);
 109                goto err_free;
 110        }
 111
 112        rc = -ENOMEM;
 113        dev->base = (struct tah_regs __iomem *)ioremap(regs.start,
 114                                               sizeof(struct tah_regs));
 115        if (dev->base == NULL) {
 116                printk(KERN_ERR "%s: Can't map device registers!\n",
 117                       np->full_name);
 118                goto err_free;
 119        }
 120
 121        dev_set_drvdata(&ofdev->dev, dev);
 122
 123        /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */
 124        tah_reset(ofdev);
 125
 126        printk(KERN_INFO
 127               "TAH %s initialized\n", ofdev->dev.of_node->full_name);
 128        wmb();
 129
 130        return 0;
 131
 132 err_free:
 133        kfree(dev);
 134 err_gone:
 135        return rc;
 136}
 137
 138static int tah_remove(struct platform_device *ofdev)
 139{
 140        struct tah_instance *dev = dev_get_drvdata(&ofdev->dev);
 141
 142        dev_set_drvdata(&ofdev->dev, NULL);
 143
 144        WARN_ON(dev->users != 0);
 145
 146        iounmap(dev->base);
 147        kfree(dev);
 148
 149        return 0;
 150}
 151
 152static struct of_device_id tah_match[] =
 153{
 154        {
 155                .compatible     = "ibm,tah",
 156        },
 157        /* For backward compat with old DT */
 158        {
 159                .type           = "tah",
 160        },
 161        {},
 162};
 163
 164static struct platform_driver tah_driver = {
 165        .driver = {
 166                .name = "emac-tah",
 167                .owner = THIS_MODULE,
 168                .of_match_table = tah_match,
 169        },
 170        .probe = tah_probe,
 171        .remove = tah_remove,
 172};
 173
 174int __init tah_init(void)
 175{
 176        return platform_driver_register(&tah_driver);
 177}
 178
 179void tah_exit(void)
 180{
 181        platform_driver_unregister(&tah_driver);
 182}
 183