1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * drivers/net/ethernet/ibm/emac/rgmii.c
4 *
5 * Driver for PowerPC 4xx on-chip ethernet controller, RGMII bridge support.
6 *
7 * Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
8 *                <benh@kernel.crashing.org>
9 *
10 * Based on the arch/ppc version of the driver:
11 *
12 * Copyright (c) 2004, 2005 Zultys Technologies.
13 * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
14 *
15 * Based on original work by
16 * 	Matt Porter <mporter@kernel.crashing.org>
17 * 	Copyright 2004 MontaVista Software, Inc.
18 */
19#include <linux/slab.h>
20#include <linux/kernel.h>
21#include <linux/ethtool.h>
22#include <linux/of_address.h>
23#include <asm/io.h>
24
25#include "emac.h"
26#include "debug.h"
27
28// XXX FIXME: Axon seems to support a subset of the RGMII, we
29// thus need to take that into account and possibly change some
30// of the bit settings below that don't seem to quite match the
31// AXON spec
32
33/* RGMIIx_FER */
34#define RGMII_FER_MASK(idx)	(0x7 << ((idx) * 4))
35#define RGMII_FER_RTBI(idx)	(0x4 << ((idx) * 4))
36#define RGMII_FER_RGMII(idx)	(0x5 << ((idx) * 4))
37#define RGMII_FER_TBI(idx)	(0x6 << ((idx) * 4))
38#define RGMII_FER_GMII(idx)	(0x7 << ((idx) * 4))
39#define RGMII_FER_MII(idx)	RGMII_FER_GMII(idx)
40
41/* RGMIIx_SSR */
42#define RGMII_SSR_MASK(idx)	(0x7 << ((idx) * 8))
43#define RGMII_SSR_10(idx)	(0x1 << ((idx) * 8))
44#define RGMII_SSR_100(idx)	(0x2 << ((idx) * 8))
45#define RGMII_SSR_1000(idx)	(0x4 << ((idx) * 8))
46
47/* RGMII bridge supports only GMII/TBI and RGMII/RTBI PHYs */
48static inline int rgmii_valid_mode(int phy_mode)
49{
50	return  phy_interface_mode_is_rgmii(phy_mode) ||
51		phy_mode == PHY_INTERFACE_MODE_GMII ||
52		phy_mode == PHY_INTERFACE_MODE_MII ||
53		phy_mode == PHY_INTERFACE_MODE_TBI ||
54		phy_mode == PHY_INTERFACE_MODE_RTBI;
55}
56
57static inline u32 rgmii_mode_mask(int mode, int input)
58{
59	switch (mode) {
60	case PHY_INTERFACE_MODE_RGMII:
61	case PHY_INTERFACE_MODE_RGMII_ID:
62	case PHY_INTERFACE_MODE_RGMII_RXID:
63	case PHY_INTERFACE_MODE_RGMII_TXID:
64		return RGMII_FER_RGMII(input);
65	case PHY_INTERFACE_MODE_TBI:
66		return RGMII_FER_TBI(input);
67	case PHY_INTERFACE_MODE_GMII:
68		return RGMII_FER_GMII(input);
69	case PHY_INTERFACE_MODE_MII:
70		return RGMII_FER_MII(input);
71	case PHY_INTERFACE_MODE_RTBI:
72		return RGMII_FER_RTBI(input);
73	default:
74		BUG();
75	}
76}
77
78int rgmii_attach(struct platform_device *ofdev, int input, int mode)
79{
80	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
81	struct rgmii_regs __iomem *p = dev->base;
82
83	RGMII_DBG(dev, "attach(%d)" NL, input);
84
85	/* Check if we need to attach to a RGMII */
86	if (input < 0 || !rgmii_valid_mode(mode)) {
87		printk(KERN_ERR "%pOF: unsupported settings !\n",
88		       ofdev->dev.of_node);
89		return -ENODEV;
90	}
91
92	mutex_lock(&dev->lock);
93
94	/* Enable this input */
95	out_be32(&p->fer, in_be32(&p->fer) | rgmii_mode_mask(mode, input));
96
97	printk(KERN_NOTICE "%pOF: input %d in %s mode\n",
98	       ofdev->dev.of_node, input, phy_modes(mode));
99
100	++dev->users;
101
102	mutex_unlock(&dev->lock);
103
104	return 0;
105}
106
107void rgmii_set_speed(struct platform_device *ofdev, int input, int speed)
108{
109	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
110	struct rgmii_regs __iomem *p = dev->base;
111	u32 ssr;
112
113	mutex_lock(&dev->lock);
114
115	ssr = in_be32(&p->ssr) & ~RGMII_SSR_MASK(input);
116
117	RGMII_DBG(dev, "speed(%d, %d)" NL, input, speed);
118
119	if (speed == SPEED_1000)
120		ssr |= RGMII_SSR_1000(input);
121	else if (speed == SPEED_100)
122		ssr |= RGMII_SSR_100(input);
123	else if (speed == SPEED_10)
124		ssr |= RGMII_SSR_10(input);
125
126	out_be32(&p->ssr, ssr);
127
128	mutex_unlock(&dev->lock);
129}
130
131void rgmii_get_mdio(struct platform_device *ofdev, int input)
132{
133	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
134	struct rgmii_regs __iomem *p = dev->base;
135	u32 fer;
136
137	RGMII_DBG2(dev, "get_mdio(%d)" NL, input);
138
139	if (!(dev->flags & EMAC_RGMII_FLAG_HAS_MDIO))
140		return;
141
142	mutex_lock(&dev->lock);
143
144	fer = in_be32(&p->fer);
145	fer |= 0x00080000u >> input;
146	out_be32(&p->fer, fer);
147	(void)in_be32(&p->fer);
148
149	DBG2(dev, " fer = 0x%08x\n", fer);
150}
151
152void rgmii_put_mdio(struct platform_device *ofdev, int input)
153{
154	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
155	struct rgmii_regs __iomem *p = dev->base;
156	u32 fer;
157
158	RGMII_DBG2(dev, "put_mdio(%d)" NL, input);
159
160	if (!(dev->flags & EMAC_RGMII_FLAG_HAS_MDIO))
161		return;
162
163	fer = in_be32(&p->fer);
164	fer &= ~(0x00080000u >> input);
165	out_be32(&p->fer, fer);
166	(void)in_be32(&p->fer);
167
168	DBG2(dev, " fer = 0x%08x\n", fer);
169
170	mutex_unlock(&dev->lock);
171}
172
173void rgmii_detach(struct platform_device *ofdev, int input)
174{
175	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
176	struct rgmii_regs __iomem *p;
177
178	BUG_ON(!dev || dev->users == 0);
179	p = dev->base;
180
181	mutex_lock(&dev->lock);
182
183	RGMII_DBG(dev, "detach(%d)" NL, input);
184
185	/* Disable this input */
186	out_be32(&p->fer, in_be32(&p->fer) & ~RGMII_FER_MASK(input));
187
188	--dev->users;
189
190	mutex_unlock(&dev->lock);
191}
192
193int rgmii_get_regs_len(struct platform_device *ofdev)
194{
195	return sizeof(struct emac_ethtool_regs_subhdr) +
196		sizeof(struct rgmii_regs);
197}
198
199void *rgmii_dump_regs(struct platform_device *ofdev, void *buf)
200{
201	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
202	struct emac_ethtool_regs_subhdr *hdr = buf;
203	struct rgmii_regs *regs = (struct rgmii_regs *)(hdr + 1);
204
205	hdr->version = 0;
206	hdr->index = 0; /* for now, are there chips with more than one
207			 * rgmii ? if yes, then we'll add a cell_index
208			 * like we do for emac
209			 */
210	memcpy_fromio(regs, dev->base, sizeof(struct rgmii_regs));
211	return regs + 1;
212}
213
214
215static int rgmii_probe(struct platform_device *ofdev)
216{
217	struct device_node *np = ofdev->dev.of_node;
218	struct rgmii_instance *dev;
219	struct resource regs;
220	int rc;
221
222	rc = -ENOMEM;
223	dev = kzalloc(sizeof(struct rgmii_instance), GFP_KERNEL);
224	if (dev == NULL)
225		goto err_gone;
226
227	mutex_init(&dev->lock);
228	dev->ofdev = ofdev;
229
230	rc = -ENXIO;
231	if (of_address_to_resource(np, 0, &regs)) {
232		printk(KERN_ERR "%pOF: Can't get registers address\n", np);
233		goto err_free;
234	}
235
236	rc = -ENOMEM;
237	dev->base = (struct rgmii_regs __iomem *)ioremap(regs.start,
238						 sizeof(struct rgmii_regs));
239	if (dev->base == NULL) {
240		printk(KERN_ERR "%pOF: Can't map device registers!\n", np);
241		goto err_free;
242	}
243
244	/* Check for RGMII flags */
245	if (of_get_property(ofdev->dev.of_node, "has-mdio", NULL))
246		dev->flags |= EMAC_RGMII_FLAG_HAS_MDIO;
247
248	/* CAB lacks the right properties, fix this up */
249	if (of_device_is_compatible(ofdev->dev.of_node, "ibm,rgmii-axon"))
250		dev->flags |= EMAC_RGMII_FLAG_HAS_MDIO;
251
252	DBG2(dev, " Boot FER = 0x%08x, SSR = 0x%08x\n",
253	     in_be32(&dev->base->fer), in_be32(&dev->base->ssr));
254
255	/* Disable all inputs by default */
256	out_be32(&dev->base->fer, 0);
257
258	printk(KERN_INFO
259	       "RGMII %pOF initialized with%s MDIO support\n",
260	       ofdev->dev.of_node,
261	       (dev->flags & EMAC_RGMII_FLAG_HAS_MDIO) ? "" : "out");
262
263	wmb();
264	platform_set_drvdata(ofdev, dev);
265
266	return 0;
267
268 err_free:
269	kfree(dev);
270 err_gone:
271	return rc;
272}
273
274static int rgmii_remove(struct platform_device *ofdev)
275{
276	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
277
278	WARN_ON(dev->users != 0);
279
280	iounmap(dev->base);
281	kfree(dev);
282
283	return 0;
284}
285
286static const struct of_device_id rgmii_match[] =
287{
288	{
289		.compatible	= "ibm,rgmii",
290	},
291	{
292		.type		= "emac-rgmii",
293	},
294	{},
295};
296
297static struct platform_driver rgmii_driver = {
298	.driver = {
299		.name = "emac-rgmii",
300		.of_match_table = rgmii_match,
301	},
302	.probe = rgmii_probe,
303	.remove = rgmii_remove,
304};
305
306int __init rgmii_init(void)
307{
308	return platform_driver_register(&rgmii_driver);
309}
310
311void rgmii_exit(void)
312{
313	platform_driver_unregister(&rgmii_driver);
314}
315