drivers/net/ibm_newemac/tah.c

   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
  26 int __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
  38 void 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
  47 void 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
  68 int tah_get_regs_len(struct of_device *ofdev)
  69 {
  70         return sizeof(struct emac_ethtool_regs_subhdr) +
  71                 sizeof(struct tah_regs);
  72 }
  73
  74 void *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
  89 static 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
 141 static 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
 155 static 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
 167 static 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
 175 int __init tah_init(void)
 176 {
 177         return of_register_platform_driver(&tah_driver);
 178 }
 179
 180 void tah_exit(void)
 181 {
 182         of_unregister_platform_driver(&tah_driver);
 183 }