xref: /openbmc/linux/drivers/net/ethernet/ibm/emac/rgmii.c (revision ded1ffea)
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 */
50 static 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 
59 static 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 
80 int 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 
109 void 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 
133 void 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 
154 void 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 
175 void 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 
195 int rgmii_get_regs_len(struct platform_device *ofdev)
196 {
197 	return sizeof(struct emac_ethtool_regs_subhdr) +
198 		sizeof(struct rgmii_regs);
199 }
200 
201 void *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 
217 static 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 
276 static int 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 	return 0;
286 }
287 
288 static const struct of_device_id rgmii_match[] =
289 {
290 	{
291 		.compatible	= "ibm,rgmii",
292 	},
293 	{
294 		.type		= "emac-rgmii",
295 	},
296 	{},
297 };
298 
299 static struct platform_driver rgmii_driver = {
300 	.driver = {
301 		.name = "emac-rgmii",
302 		.of_match_table = rgmii_match,
303 	},
304 	.probe = rgmii_probe,
305 	.remove = rgmii_remove,
306 };
307 
308 int __init rgmii_init(void)
309 {
310 	return platform_driver_register(&rgmii_driver);
311 }
312 
313 void rgmii_exit(void)
314 {
315 	platform_driver_unregister(&rgmii_driver);
316 }
317