xref: /openbmc/linux/drivers/net/phy/lxt.c (revision 3805e6a1)
1 /*
2  * drivers/net/phy/lxt.c
3  *
4  * Driver for Intel LXT PHYs
5  *
6  * Author: Andy Fleming
7  *
8  * Copyright (c) 2004 Freescale Semiconductor, Inc.
9  *
10  * This program is free software; you can redistribute  it and/or modify it
11  * under  the terms of  the GNU General  Public License as published by the
12  * Free Software Foundation;  either version 2 of the  License, or (at your
13  * option) any later version.
14  *
15  */
16 #include <linux/kernel.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/unistd.h>
20 #include <linux/interrupt.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
23 #include <linux/netdevice.h>
24 #include <linux/etherdevice.h>
25 #include <linux/skbuff.h>
26 #include <linux/spinlock.h>
27 #include <linux/mm.h>
28 #include <linux/module.h>
29 #include <linux/mii.h>
30 #include <linux/ethtool.h>
31 #include <linux/phy.h>
32 
33 #include <asm/io.h>
34 #include <asm/irq.h>
35 #include <asm/uaccess.h>
36 
37 /* The Level one LXT970 is used by many boards				     */
38 
39 #define MII_LXT970_IER       17  /* Interrupt Enable Register */
40 
41 #define MII_LXT970_IER_IEN	0x0002
42 
43 #define MII_LXT970_ISR       18  /* Interrupt Status Register */
44 
45 #define MII_LXT970_CONFIG    19  /* Configuration Register    */
46 
47 /* ------------------------------------------------------------------------- */
48 /* The Level one LXT971 is used on some of my custom boards                  */
49 
50 /* register definitions for the 971 */
51 #define MII_LXT971_IER		18  /* Interrupt Enable Register */
52 #define MII_LXT971_IER_IEN	0x00f2
53 
54 #define MII_LXT971_ISR		19  /* Interrupt Status Register */
55 
56 /* register definitions for the 973 */
57 #define MII_LXT973_PCR 16 /* Port Configuration Register */
58 #define PCR_FIBER_SELECT 1
59 
60 MODULE_DESCRIPTION("Intel LXT PHY driver");
61 MODULE_AUTHOR("Andy Fleming");
62 MODULE_LICENSE("GPL");
63 
64 static int lxt970_ack_interrupt(struct phy_device *phydev)
65 {
66 	int err;
67 
68 	err = phy_read(phydev, MII_BMSR);
69 
70 	if (err < 0)
71 		return err;
72 
73 	err = phy_read(phydev, MII_LXT970_ISR);
74 
75 	if (err < 0)
76 		return err;
77 
78 	return 0;
79 }
80 
81 static int lxt970_config_intr(struct phy_device *phydev)
82 {
83 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
84 		return phy_write(phydev, MII_LXT970_IER, MII_LXT970_IER_IEN);
85 	else
86 		return phy_write(phydev, MII_LXT970_IER, 0);
87 }
88 
89 static int lxt970_config_init(struct phy_device *phydev)
90 {
91 	return phy_write(phydev, MII_LXT970_CONFIG, 0);
92 }
93 
94 
95 static int lxt971_ack_interrupt(struct phy_device *phydev)
96 {
97 	int err = phy_read(phydev, MII_LXT971_ISR);
98 
99 	if (err < 0)
100 		return err;
101 
102 	return 0;
103 }
104 
105 static int lxt971_config_intr(struct phy_device *phydev)
106 {
107 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
108 		return phy_write(phydev, MII_LXT971_IER, MII_LXT971_IER_IEN);
109 	else
110 		return phy_write(phydev, MII_LXT971_IER, 0);
111 }
112 
113 /*
114  * A2 version of LXT973 chip has an ERRATA: it randomly return the contents
115  * of the previous even register when you read a odd register regularly
116  */
117 
118 static int lxt973a2_update_link(struct phy_device *phydev)
119 {
120 	int status;
121 	int control;
122 	int retry = 8; /* we try 8 times */
123 
124 	/* Do a fake read */
125 	status = phy_read(phydev, MII_BMSR);
126 
127 	if (status < 0)
128 		return status;
129 
130 	control = phy_read(phydev, MII_BMCR);
131 	if (control < 0)
132 		return control;
133 
134 	do {
135 		/* Read link and autonegotiation status */
136 		status = phy_read(phydev, MII_BMSR);
137 	} while (status >= 0 && retry-- && status == control);
138 
139 	if (status < 0)
140 		return status;
141 
142 	if ((status & BMSR_LSTATUS) == 0)
143 		phydev->link = 0;
144 	else
145 		phydev->link = 1;
146 
147 	return 0;
148 }
149 
150 static int lxt973a2_read_status(struct phy_device *phydev)
151 {
152 	int adv;
153 	int err;
154 	int lpa;
155 	int lpagb = 0;
156 
157 	/* Update the link, but return if there was an error */
158 	err = lxt973a2_update_link(phydev);
159 	if (err)
160 		return err;
161 
162 	if (AUTONEG_ENABLE == phydev->autoneg) {
163 		int retry = 1;
164 
165 		adv = phy_read(phydev, MII_ADVERTISE);
166 
167 		if (adv < 0)
168 			return adv;
169 
170 		do {
171 			lpa = phy_read(phydev, MII_LPA);
172 
173 			if (lpa < 0)
174 				return lpa;
175 
176 			/* If both registers are equal, it is suspect but not
177 			* impossible, hence a new try
178 			*/
179 		} while (lpa == adv && retry--);
180 
181 		lpa &= adv;
182 
183 		phydev->speed = SPEED_10;
184 		phydev->duplex = DUPLEX_HALF;
185 		phydev->pause = phydev->asym_pause = 0;
186 
187 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
188 			phydev->speed = SPEED_1000;
189 
190 			if (lpagb & LPA_1000FULL)
191 				phydev->duplex = DUPLEX_FULL;
192 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
193 			phydev->speed = SPEED_100;
194 
195 			if (lpa & LPA_100FULL)
196 				phydev->duplex = DUPLEX_FULL;
197 		} else {
198 			if (lpa & LPA_10FULL)
199 				phydev->duplex = DUPLEX_FULL;
200 		}
201 
202 		if (phydev->duplex == DUPLEX_FULL) {
203 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
204 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
205 		}
206 	} else {
207 		int bmcr = phy_read(phydev, MII_BMCR);
208 
209 		if (bmcr < 0)
210 			return bmcr;
211 
212 		if (bmcr & BMCR_FULLDPLX)
213 			phydev->duplex = DUPLEX_FULL;
214 		else
215 			phydev->duplex = DUPLEX_HALF;
216 
217 		if (bmcr & BMCR_SPEED1000)
218 			phydev->speed = SPEED_1000;
219 		else if (bmcr & BMCR_SPEED100)
220 			phydev->speed = SPEED_100;
221 		else
222 			phydev->speed = SPEED_10;
223 
224 		phydev->pause = phydev->asym_pause = 0;
225 	}
226 
227 	return 0;
228 }
229 
230 static int lxt973_probe(struct phy_device *phydev)
231 {
232 	int val = phy_read(phydev, MII_LXT973_PCR);
233 
234 	if (val & PCR_FIBER_SELECT) {
235 		/*
236 		 * If fiber is selected, then the only correct setting
237 		 * is 100Mbps, full duplex, and auto negotiation off.
238 		 */
239 		val = phy_read(phydev, MII_BMCR);
240 		val |= (BMCR_SPEED100 | BMCR_FULLDPLX);
241 		val &= ~BMCR_ANENABLE;
242 		phy_write(phydev, MII_BMCR, val);
243 		/* Remember that the port is in fiber mode. */
244 		phydev->priv = lxt973_probe;
245 	} else {
246 		phydev->priv = NULL;
247 	}
248 	return 0;
249 }
250 
251 static int lxt973_config_aneg(struct phy_device *phydev)
252 {
253 	/* Do nothing if port is in fiber mode. */
254 	return phydev->priv ? 0 : genphy_config_aneg(phydev);
255 }
256 
257 static struct phy_driver lxt97x_driver[] = {
258 {
259 	.phy_id		= 0x78100000,
260 	.name		= "LXT970",
261 	.phy_id_mask	= 0xfffffff0,
262 	.features	= PHY_BASIC_FEATURES,
263 	.flags		= PHY_HAS_INTERRUPT,
264 	.config_init	= lxt970_config_init,
265 	.config_aneg	= genphy_config_aneg,
266 	.read_status	= genphy_read_status,
267 	.ack_interrupt	= lxt970_ack_interrupt,
268 	.config_intr	= lxt970_config_intr,
269 }, {
270 	.phy_id		= 0x001378e0,
271 	.name		= "LXT971",
272 	.phy_id_mask	= 0xfffffff0,
273 	.features	= PHY_BASIC_FEATURES,
274 	.flags		= PHY_HAS_INTERRUPT,
275 	.config_aneg	= genphy_config_aneg,
276 	.read_status	= genphy_read_status,
277 	.ack_interrupt	= lxt971_ack_interrupt,
278 	.config_intr	= lxt971_config_intr,
279 }, {
280 	.phy_id		= 0x00137a10,
281 	.name		= "LXT973-A2",
282 	.phy_id_mask	= 0xffffffff,
283 	.features	= PHY_BASIC_FEATURES,
284 	.flags		= 0,
285 	.probe		= lxt973_probe,
286 	.config_aneg	= lxt973_config_aneg,
287 	.read_status	= lxt973a2_read_status,
288 }, {
289 	.phy_id		= 0x00137a10,
290 	.name		= "LXT973",
291 	.phy_id_mask	= 0xfffffff0,
292 	.features	= PHY_BASIC_FEATURES,
293 	.flags		= 0,
294 	.probe		= lxt973_probe,
295 	.config_aneg	= lxt973_config_aneg,
296 	.read_status	= genphy_read_status,
297 } };
298 
299 module_phy_driver(lxt97x_driver);
300 
301 static struct mdio_device_id __maybe_unused lxt_tbl[] = {
302 	{ 0x78100000, 0xfffffff0 },
303 	{ 0x001378e0, 0xfffffff0 },
304 	{ 0x00137a10, 0xfffffff0 },
305 	{ }
306 };
307 
308 MODULE_DEVICE_TABLE(mdio, lxt_tbl);
309