xref: /openbmc/linux/drivers/net/ethernet/ibm/emac/rgmii.c (revision 1edd0337)
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 */
48 static 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 
57 static 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 
78 int 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 
107 void 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 
131 void 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 
152 void 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 
173 void 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 
193 int rgmii_get_regs_len(struct platform_device *ofdev)
194 {
195 	return sizeof(struct emac_ethtool_regs_subhdr) +
196 		sizeof(struct rgmii_regs);
197 }
198 
199 void *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 
215 static 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_property_read_bool(ofdev->dev.of_node, "has-mdio"))
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 
274 static 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 
286 static const struct of_device_id rgmii_match[] =
287 {
288 	{
289 		.compatible	= "ibm,rgmii",
290 	},
291 	{
292 		.type		= "emac-rgmii",
293 	},
294 	{},
295 };
296 
297 static 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 
306 int __init rgmii_init(void)
307 {
308 	return platform_driver_register(&rgmii_driver);
309 }
310 
311 void rgmii_exit(void)
312 {
313 	platform_driver_unregister(&rgmii_driver);
314 }
315