xref: /openbmc/linux/drivers/net/ethernet/ibm/emac/rgmii.c (revision 79f08d9e)
1 /*
2  * drivers/net/ethernet/ibm/emac/rgmii.c
3  *
4  * Driver for PowerPC 4xx on-chip ethernet controller, RGMII bridge 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 (c) 2004, 2005 Zultys Technologies.
12  * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
13  *
14  * Based on original work by
15  * 	Matt Porter <mporter@kernel.crashing.org>
16  * 	Copyright 2004 MontaVista Software, Inc.
17  *
18  * This program is free software; you can redistribute  it and/or modify it
19  * under  the terms of  the GNU General  Public License as published by the
20  * Free Software Foundation;  either version 2 of the  License, or (at your
21  * option) any later version.
22  *
23  */
24 #include <linux/slab.h>
25 #include <linux/kernel.h>
26 #include <linux/ethtool.h>
27 #include <linux/of_address.h>
28 #include <asm/io.h>
29 
30 #include "emac.h"
31 #include "debug.h"
32 
33 // XXX FIXME: Axon seems to support a subset of the RGMII, we
34 // thus need to take that into account and possibly change some
35 // of the bit settings below that don't seem to quite match the
36 // AXON spec
37 
38 /* RGMIIx_FER */
39 #define RGMII_FER_MASK(idx)	(0x7 << ((idx) * 4))
40 #define RGMII_FER_RTBI(idx)	(0x4 << ((idx) * 4))
41 #define RGMII_FER_RGMII(idx)	(0x5 << ((idx) * 4))
42 #define RGMII_FER_TBI(idx)	(0x6 << ((idx) * 4))
43 #define RGMII_FER_GMII(idx)	(0x7 << ((idx) * 4))
44 #define RGMII_FER_MII(idx)	RGMII_FER_GMII(idx)
45 
46 /* RGMIIx_SSR */
47 #define RGMII_SSR_MASK(idx)	(0x7 << ((idx) * 8))
48 #define RGMII_SSR_100(idx)	(0x2 << ((idx) * 8))
49 #define RGMII_SSR_1000(idx)	(0x4 << ((idx) * 8))
50 
51 /* RGMII bridge supports only GMII/TBI and RGMII/RTBI PHYs */
52 static inline int rgmii_valid_mode(int phy_mode)
53 {
54 	return  phy_mode == PHY_MODE_GMII ||
55 		phy_mode == PHY_MODE_MII ||
56 		phy_mode == PHY_MODE_RGMII ||
57 		phy_mode == PHY_MODE_TBI ||
58 		phy_mode == PHY_MODE_RTBI;
59 }
60 
61 static inline const char *rgmii_mode_name(int mode)
62 {
63 	switch (mode) {
64 	case PHY_MODE_RGMII:
65 		return "RGMII";
66 	case PHY_MODE_TBI:
67 		return "TBI";
68 	case PHY_MODE_GMII:
69 		return "GMII";
70 	case PHY_MODE_MII:
71 		return "MII";
72 	case PHY_MODE_RTBI:
73 		return "RTBI";
74 	default:
75 		BUG();
76 	}
77 }
78 
79 static inline u32 rgmii_mode_mask(int mode, int input)
80 {
81 	switch (mode) {
82 	case PHY_MODE_RGMII:
83 		return RGMII_FER_RGMII(input);
84 	case PHY_MODE_TBI:
85 		return RGMII_FER_TBI(input);
86 	case PHY_MODE_GMII:
87 		return RGMII_FER_GMII(input);
88 	case PHY_MODE_MII:
89 		return RGMII_FER_MII(input);
90 	case PHY_MODE_RTBI:
91 		return RGMII_FER_RTBI(input);
92 	default:
93 		BUG();
94 	}
95 }
96 
97 int rgmii_attach(struct platform_device *ofdev, int input, int mode)
98 {
99 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
100 	struct rgmii_regs __iomem *p = dev->base;
101 
102 	RGMII_DBG(dev, "attach(%d)" NL, input);
103 
104 	/* Check if we need to attach to a RGMII */
105 	if (input < 0 || !rgmii_valid_mode(mode)) {
106 		printk(KERN_ERR "%s: unsupported settings !\n",
107 		       ofdev->dev.of_node->full_name);
108 		return -ENODEV;
109 	}
110 
111 	mutex_lock(&dev->lock);
112 
113 	/* Enable this input */
114 	out_be32(&p->fer, in_be32(&p->fer) | rgmii_mode_mask(mode, input));
115 
116 	printk(KERN_NOTICE "%s: input %d in %s mode\n",
117 	       ofdev->dev.of_node->full_name, input, rgmii_mode_name(mode));
118 
119 	++dev->users;
120 
121 	mutex_unlock(&dev->lock);
122 
123 	return 0;
124 }
125 
126 void rgmii_set_speed(struct platform_device *ofdev, int input, int speed)
127 {
128 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
129 	struct rgmii_regs __iomem *p = dev->base;
130 	u32 ssr;
131 
132 	mutex_lock(&dev->lock);
133 
134 	ssr = in_be32(&p->ssr) & ~RGMII_SSR_MASK(input);
135 
136 	RGMII_DBG(dev, "speed(%d, %d)" NL, input, speed);
137 
138 	if (speed == SPEED_1000)
139 		ssr |= RGMII_SSR_1000(input);
140 	else if (speed == SPEED_100)
141 		ssr |= RGMII_SSR_100(input);
142 
143 	out_be32(&p->ssr, ssr);
144 
145 	mutex_unlock(&dev->lock);
146 }
147 
148 void rgmii_get_mdio(struct platform_device *ofdev, int input)
149 {
150 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
151 	struct rgmii_regs __iomem *p = dev->base;
152 	u32 fer;
153 
154 	RGMII_DBG2(dev, "get_mdio(%d)" NL, input);
155 
156 	if (!(dev->flags & EMAC_RGMII_FLAG_HAS_MDIO))
157 		return;
158 
159 	mutex_lock(&dev->lock);
160 
161 	fer = in_be32(&p->fer);
162 	fer |= 0x00080000u >> input;
163 	out_be32(&p->fer, fer);
164 	(void)in_be32(&p->fer);
165 
166 	DBG2(dev, " fer = 0x%08x\n", fer);
167 }
168 
169 void rgmii_put_mdio(struct platform_device *ofdev, int input)
170 {
171 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
172 	struct rgmii_regs __iomem *p = dev->base;
173 	u32 fer;
174 
175 	RGMII_DBG2(dev, "put_mdio(%d)" NL, input);
176 
177 	if (!(dev->flags & EMAC_RGMII_FLAG_HAS_MDIO))
178 		return;
179 
180 	fer = in_be32(&p->fer);
181 	fer &= ~(0x00080000u >> input);
182 	out_be32(&p->fer, fer);
183 	(void)in_be32(&p->fer);
184 
185 	DBG2(dev, " fer = 0x%08x\n", fer);
186 
187 	mutex_unlock(&dev->lock);
188 }
189 
190 void rgmii_detach(struct platform_device *ofdev, int input)
191 {
192 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
193 	struct rgmii_regs __iomem *p;
194 
195 	BUG_ON(!dev || dev->users == 0);
196 	p = dev->base;
197 
198 	mutex_lock(&dev->lock);
199 
200 	RGMII_DBG(dev, "detach(%d)" NL, input);
201 
202 	/* Disable this input */
203 	out_be32(&p->fer, in_be32(&p->fer) & ~RGMII_FER_MASK(input));
204 
205 	--dev->users;
206 
207 	mutex_unlock(&dev->lock);
208 }
209 
210 int rgmii_get_regs_len(struct platform_device *ofdev)
211 {
212 	return sizeof(struct emac_ethtool_regs_subhdr) +
213 		sizeof(struct rgmii_regs);
214 }
215 
216 void *rgmii_dump_regs(struct platform_device *ofdev, void *buf)
217 {
218 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
219 	struct emac_ethtool_regs_subhdr *hdr = buf;
220 	struct rgmii_regs *regs = (struct rgmii_regs *)(hdr + 1);
221 
222 	hdr->version = 0;
223 	hdr->index = 0; /* for now, are there chips with more than one
224 			 * rgmii ? if yes, then we'll add a cell_index
225 			 * like we do for emac
226 			 */
227 	memcpy_fromio(regs, dev->base, sizeof(struct rgmii_regs));
228 	return regs + 1;
229 }
230 
231 
232 static int rgmii_probe(struct platform_device *ofdev)
233 {
234 	struct device_node *np = ofdev->dev.of_node;
235 	struct rgmii_instance *dev;
236 	struct resource regs;
237 	int rc;
238 
239 	rc = -ENOMEM;
240 	dev = kzalloc(sizeof(struct rgmii_instance), GFP_KERNEL);
241 	if (dev == NULL)
242 		goto err_gone;
243 
244 	mutex_init(&dev->lock);
245 	dev->ofdev = ofdev;
246 
247 	rc = -ENXIO;
248 	if (of_address_to_resource(np, 0, &regs)) {
249 		printk(KERN_ERR "%s: Can't get registers address\n",
250 		       np->full_name);
251 		goto err_free;
252 	}
253 
254 	rc = -ENOMEM;
255 	dev->base = (struct rgmii_regs __iomem *)ioremap(regs.start,
256 						 sizeof(struct rgmii_regs));
257 	if (dev->base == NULL) {
258 		printk(KERN_ERR "%s: Can't map device registers!\n",
259 		       np->full_name);
260 		goto err_free;
261 	}
262 
263 	/* Check for RGMII flags */
264 	if (of_get_property(ofdev->dev.of_node, "has-mdio", NULL))
265 		dev->flags |= EMAC_RGMII_FLAG_HAS_MDIO;
266 
267 	/* CAB lacks the right properties, fix this up */
268 	if (of_device_is_compatible(ofdev->dev.of_node, "ibm,rgmii-axon"))
269 		dev->flags |= EMAC_RGMII_FLAG_HAS_MDIO;
270 
271 	DBG2(dev, " Boot FER = 0x%08x, SSR = 0x%08x\n",
272 	     in_be32(&dev->base->fer), in_be32(&dev->base->ssr));
273 
274 	/* Disable all inputs by default */
275 	out_be32(&dev->base->fer, 0);
276 
277 	printk(KERN_INFO
278 	       "RGMII %s initialized with%s MDIO support\n",
279 	       ofdev->dev.of_node->full_name,
280 	       (dev->flags & EMAC_RGMII_FLAG_HAS_MDIO) ? "" : "out");
281 
282 	wmb();
283 	platform_set_drvdata(ofdev, dev);
284 
285 	return 0;
286 
287  err_free:
288 	kfree(dev);
289  err_gone:
290 	return rc;
291 }
292 
293 static int rgmii_remove(struct platform_device *ofdev)
294 {
295 	struct rgmii_instance *dev = platform_get_drvdata(ofdev);
296 
297 	WARN_ON(dev->users != 0);
298 
299 	iounmap(dev->base);
300 	kfree(dev);
301 
302 	return 0;
303 }
304 
305 static struct of_device_id rgmii_match[] =
306 {
307 	{
308 		.compatible	= "ibm,rgmii",
309 	},
310 	{
311 		.type		= "emac-rgmii",
312 	},
313 	{},
314 };
315 
316 static struct platform_driver rgmii_driver = {
317 	.driver = {
318 		.name = "emac-rgmii",
319 		.owner = THIS_MODULE,
320 		.of_match_table = rgmii_match,
321 	},
322 	.probe = rgmii_probe,
323 	.remove = rgmii_remove,
324 };
325 
326 int __init rgmii_init(void)
327 {
328 	return platform_driver_register(&rgmii_driver);
329 }
330 
331 void rgmii_exit(void)
332 {
333 	platform_driver_unregister(&rgmii_driver);
334 }
335