Merge commit 'v2.6.28-rc7'; branch 'x86/dumpstack' into tracing/ftrace
[linux-2.6] / 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 }