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