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 <linux/of_address.h>
  22#include <asm/io.h>
  23
  24#include "emac.h"
  25#include "core.h"
  26
  27int tah_attach(struct platform_device *ofdev, int channel)
  28{
  29        struct tah_instance *dev = platform_get_drvdata(ofdev);
  30
  31        mutex_lock(&dev->lock);
  32        /* Reset has been done at probe() time... nothing else to do for now */
  33        ++dev->users;
  34        mutex_unlock(&dev->lock);
  35
  36        return 0;
  37}
  38
  39void tah_detach(struct platform_device *ofdev, int channel)
  40{
  41        struct tah_instance *dev = platform_get_drvdata(ofdev);
  42
  43        mutex_lock(&dev->lock);
  44        --dev->users;
  45        mutex_unlock(&dev->lock);
  46}
  47
  48void tah_reset(struct platform_device *ofdev)
  49{
  50        struct tah_instance *dev = platform_get_drvdata(ofdev);
  51        struct tah_regs __iomem *p = dev->base;
  52        int n;
  53
  54        /* Reset TAH */
  55        out_be32(&p->mr, TAH_MR_SR);
  56        n = 100;
  57        while ((in_be32(&p->mr) & TAH_MR_SR) && n)
  58                --n;
  59
  60        if (unlikely(!n))
  61                printk(KERN_ERR "%s: reset timeout\n",
  62                        ofdev->dev.of_node->full_name);
  63
  64        /* 10KB TAH TX FIFO accommodates the max MTU of 9000 */
  65        out_be32(&p->mr,
  66                 TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP |
  67                 TAH_MR_DIG);
  68}
  69
  70int tah_get_regs_len(struct platform_device *ofdev)
  71{
  72        return sizeof(struct emac_ethtool_regs_subhdr) +
  73                sizeof(struct tah_regs);
  74}
  75
  76void *tah_dump_regs(struct platform_device *ofdev, void *buf)
  77{
  78        struct tah_instance *dev = platform_get_drvdata(ofdev);
  79        struct emac_ethtool_regs_subhdr *hdr = buf;
  80        struct tah_regs *regs = (struct tah_regs *)(hdr + 1);
  81
  82        hdr->version = 0;
  83        hdr->index = 0; /* for now, are there chips with more than one
  84                         * zmii ? if yes, then we'll add a cell_index
  85                         * like we do for emac
  86                         */
  87        memcpy_fromio(regs, dev->base, sizeof(struct tah_regs));
  88        return regs + 1;
  89}
  90
  91static int tah_probe(struct platform_device *ofdev)
  92{
  93        struct device_node *np = ofdev->dev.of_node;
  94        struct tah_instance *dev;
  95        struct resource regs;
  96        int rc;
  97
  98        rc = -ENOMEM;
  99        dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL);
 100        if (dev == NULL)
 101                goto err_gone;
 102
 103        mutex_init(&dev->lock);
 104        dev->ofdev = ofdev;
 105
 106        rc = -ENXIO;
 107        if (of_address_to_resource(np, 0, &regs)) {
 108                printk(KERN_ERR "%s: Can't get registers address\n",
 109                       np->full_name);
 110                goto err_free;
 111        }
 112
 113        rc = -ENOMEM;
 114        dev->base = (struct tah_regs __iomem *)ioremap(regs.start,
 115                                               sizeof(struct tah_regs));
 116        if (dev->base == NULL) {
 117                printk(KERN_ERR "%s: Can't map device registers!\n",
 118                       np->full_name);
 119                goto err_free;
 120        }
 121
 122        platform_set_drvdata(ofdev, dev);
 123
 124        /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */
 125        tah_reset(ofdev);
 126
 127        printk(KERN_INFO
 128               "TAH %s initialized\n", ofdev->dev.of_node->full_name);
 129        wmb();
 130
 131        return 0;
 132
 133 err_free:
 134        kfree(dev);
 135 err_gone:
 136        return rc;
 137}
 138
 139static int tah_remove(struct platform_device *ofdev)
 140{
 141        struct tah_instance *dev = platform_get_drvdata(ofdev);
 142
 143        WARN_ON(dev->users != 0);
 144
 145        iounmap(dev->base);
 146        kfree(dev);
 147
 148        return 0;
 149}
 150
 151static const struct of_device_id tah_match[] =
 152{
 153        {
 154                .compatible     = "ibm,tah",
 155        },
 156        /* For backward compat with old DT */
 157        {
 158                .type           = "tah",
 159        },
 160        {},
 161};
 162
 163static struct platform_driver tah_driver = {
 164        .driver = {
 165                .name = "emac-tah",
 166                .of_match_table = tah_match,
 167        },
 168        .probe = tah_probe,
 169        .remove = tah_remove,
 170};
 171
 172int __init tah_init(void)
 173{
 174        return platform_driver_register(&tah_driver);
 175}
 176
 177void tah_exit(void)
 178{
 179        platform_driver_unregister(&tah_driver);
 180}
 181