1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * drivers/net/ethernet/ibm/emac/tah.c
5 * Driver for PowerPC 4xx on-chip ethernet controller, TAH support.
7 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
8 * <benh@kernel.crashing.org>
10 * Based on the arch/ppc version of the driver:
12 * Copyright 2004 MontaVista Software, Inc.
13 * Matt Porter <mporter@kernel.crashing.org>
15 * Copyright (c) 2005 Eugene Surovegin <ebs@ebshome.net>
17 #include <linux/of_address.h>
23 int tah_attach(struct platform_device *ofdev, int channel)
25 struct tah_instance *dev = platform_get_drvdata(ofdev);
27 mutex_lock(&dev->lock);
28 /* Reset has been done at probe() time... nothing else to do for now */
30 mutex_unlock(&dev->lock);
35 void tah_detach(struct platform_device *ofdev, int channel)
37 struct tah_instance *dev = platform_get_drvdata(ofdev);
39 mutex_lock(&dev->lock);
41 mutex_unlock(&dev->lock);
44 void tah_reset(struct platform_device *ofdev)
46 struct tah_instance *dev = platform_get_drvdata(ofdev);
47 struct tah_regs __iomem *p = dev->base;
51 out_be32(&p->mr, TAH_MR_SR);
53 while ((in_be32(&p->mr) & TAH_MR_SR) && n)
57 printk(KERN_ERR "%pOF: reset timeout\n", ofdev->dev.of_node);
59 /* 10KB TAH TX FIFO accommodates the max MTU of 9000 */
61 TAH_MR_CVR | TAH_MR_ST_768 | TAH_MR_TFS_10KB | TAH_MR_DTFP |
65 int tah_get_regs_len(struct platform_device *ofdev)
67 return sizeof(struct emac_ethtool_regs_subhdr) +
68 sizeof(struct tah_regs);
71 void *tah_dump_regs(struct platform_device *ofdev, void *buf)
73 struct tah_instance *dev = platform_get_drvdata(ofdev);
74 struct emac_ethtool_regs_subhdr *hdr = buf;
75 struct tah_regs *regs = (struct tah_regs *)(hdr + 1);
78 hdr->index = 0; /* for now, are there chips with more than one
79 * zmii ? if yes, then we'll add a cell_index
82 memcpy_fromio(regs, dev->base, sizeof(struct tah_regs));
86 static int tah_probe(struct platform_device *ofdev)
88 struct device_node *np = ofdev->dev.of_node;
89 struct tah_instance *dev;
94 dev = kzalloc(sizeof(struct tah_instance), GFP_KERNEL);
98 mutex_init(&dev->lock);
102 if (of_address_to_resource(np, 0, ®s)) {
103 printk(KERN_ERR "%pOF: Can't get registers address\n", np);
108 dev->base = (struct tah_regs __iomem *)ioremap(regs.start,
109 sizeof(struct tah_regs));
110 if (dev->base == NULL) {
111 printk(KERN_ERR "%pOF: Can't map device registers!\n", np);
115 platform_set_drvdata(ofdev, dev);
117 /* Initialize TAH and enable IPv4 checksum verification, no TSO yet */
120 printk(KERN_INFO "TAH %pOF initialized\n", ofdev->dev.of_node);
131 static int tah_remove(struct platform_device *ofdev)
133 struct tah_instance *dev = platform_get_drvdata(ofdev);
135 WARN_ON(dev->users != 0);
143 static const struct of_device_id tah_match[] =
146 .compatible = "ibm,tah",
148 /* For backward compat with old DT */
155 static struct platform_driver tah_driver = {
158 .of_match_table = tah_match,
161 .remove = tah_remove,
164 int __init tah_init(void)
166 return platform_driver_register(&tah_driver);
171 platform_driver_unregister(&tah_driver);