xref: /openbmc/linux/drivers/net/phy/lxt.c (revision 3213486f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * drivers/net/phy/lxt.c
4  *
5  * Driver for Intel LXT PHYs
6  *
7  * Author: Andy Fleming
8  *
9  * Copyright (c) 2004 Freescale Semiconductor, Inc.
10  */
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include <linux/unistd.h>
15 #include <linux/interrupt.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/netdevice.h>
19 #include <linux/etherdevice.h>
20 #include <linux/skbuff.h>
21 #include <linux/spinlock.h>
22 #include <linux/mm.h>
23 #include <linux/module.h>
24 #include <linux/mii.h>
25 #include <linux/ethtool.h>
26 #include <linux/phy.h>
27 
28 #include <asm/io.h>
29 #include <asm/irq.h>
30 #include <linux/uaccess.h>
31 
32 /* The Level one LXT970 is used by many boards				     */
33 
34 #define MII_LXT970_IER       17  /* Interrupt Enable Register */
35 
36 #define MII_LXT970_IER_IEN	0x0002
37 
38 #define MII_LXT970_ISR       18  /* Interrupt Status Register */
39 
40 #define MII_LXT970_CONFIG    19  /* Configuration Register    */
41 
42 /* ------------------------------------------------------------------------- */
43 /* The Level one LXT971 is used on some of my custom boards                  */
44 
45 /* register definitions for the 971 */
46 #define MII_LXT971_IER		18  /* Interrupt Enable Register */
47 #define MII_LXT971_IER_IEN	0x00f2
48 
49 #define MII_LXT971_ISR		19  /* Interrupt Status Register */
50 
51 /* register definitions for the 973 */
52 #define MII_LXT973_PCR 16 /* Port Configuration Register */
53 #define PCR_FIBER_SELECT 1
54 
55 MODULE_DESCRIPTION("Intel LXT PHY driver");
56 MODULE_AUTHOR("Andy Fleming");
57 MODULE_LICENSE("GPL");
58 
59 static int lxt970_ack_interrupt(struct phy_device *phydev)
60 {
61 	int err;
62 
63 	err = phy_read(phydev, MII_BMSR);
64 
65 	if (err < 0)
66 		return err;
67 
68 	err = phy_read(phydev, MII_LXT970_ISR);
69 
70 	if (err < 0)
71 		return err;
72 
73 	return 0;
74 }
75 
76 static int lxt970_config_intr(struct phy_device *phydev)
77 {
78 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
79 		return phy_write(phydev, MII_LXT970_IER, MII_LXT970_IER_IEN);
80 	else
81 		return phy_write(phydev, MII_LXT970_IER, 0);
82 }
83 
84 static int lxt970_config_init(struct phy_device *phydev)
85 {
86 	return phy_write(phydev, MII_LXT970_CONFIG, 0);
87 }
88 
89 
90 static int lxt971_ack_interrupt(struct phy_device *phydev)
91 {
92 	int err = phy_read(phydev, MII_LXT971_ISR);
93 
94 	if (err < 0)
95 		return err;
96 
97 	return 0;
98 }
99 
100 static int lxt971_config_intr(struct phy_device *phydev)
101 {
102 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
103 		return phy_write(phydev, MII_LXT971_IER, MII_LXT971_IER_IEN);
104 	else
105 		return phy_write(phydev, MII_LXT971_IER, 0);
106 }
107 
108 /*
109  * A2 version of LXT973 chip has an ERRATA: it randomly return the contents
110  * of the previous even register when you read a odd register regularly
111  */
112 
113 static int lxt973a2_update_link(struct phy_device *phydev)
114 {
115 	int status;
116 	int control;
117 	int retry = 8; /* we try 8 times */
118 
119 	/* Do a fake read */
120 	status = phy_read(phydev, MII_BMSR);
121 
122 	if (status < 0)
123 		return status;
124 
125 	control = phy_read(phydev, MII_BMCR);
126 	if (control < 0)
127 		return control;
128 
129 	do {
130 		/* Read link and autonegotiation status */
131 		status = phy_read(phydev, MII_BMSR);
132 	} while (status >= 0 && retry-- && status == control);
133 
134 	if (status < 0)
135 		return status;
136 
137 	if ((status & BMSR_LSTATUS) == 0)
138 		phydev->link = 0;
139 	else
140 		phydev->link = 1;
141 
142 	return 0;
143 }
144 
145 static int lxt973a2_read_status(struct phy_device *phydev)
146 {
147 	int adv;
148 	int err;
149 	int lpa;
150 
151 	/* Update the link, but return if there was an error */
152 	err = lxt973a2_update_link(phydev);
153 	if (err)
154 		return err;
155 
156 	if (AUTONEG_ENABLE == phydev->autoneg) {
157 		int retry = 1;
158 
159 		adv = phy_read(phydev, MII_ADVERTISE);
160 
161 		if (adv < 0)
162 			return adv;
163 
164 		do {
165 			lpa = phy_read(phydev, MII_LPA);
166 
167 			if (lpa < 0)
168 				return lpa;
169 
170 			/* If both registers are equal, it is suspect but not
171 			* impossible, hence a new try
172 			*/
173 		} while (lpa == adv && retry--);
174 
175 		mii_lpa_to_linkmode_lpa_t(phydev->lp_advertising, lpa);
176 
177 		lpa &= adv;
178 
179 		phydev->speed = SPEED_10;
180 		phydev->duplex = DUPLEX_HALF;
181 		phydev->pause = phydev->asym_pause = 0;
182 
183 		if (lpa & (LPA_100FULL | LPA_100HALF)) {
184 			phydev->speed = SPEED_100;
185 
186 			if (lpa & LPA_100FULL)
187 				phydev->duplex = DUPLEX_FULL;
188 		} else {
189 			if (lpa & LPA_10FULL)
190 				phydev->duplex = DUPLEX_FULL;
191 		}
192 
193 		if (phydev->duplex == DUPLEX_FULL) {
194 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
195 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
196 		}
197 	} else {
198 		int bmcr = phy_read(phydev, MII_BMCR);
199 
200 		if (bmcr < 0)
201 			return bmcr;
202 
203 		if (bmcr & BMCR_FULLDPLX)
204 			phydev->duplex = DUPLEX_FULL;
205 		else
206 			phydev->duplex = DUPLEX_HALF;
207 
208 		if (bmcr & BMCR_SPEED1000)
209 			phydev->speed = SPEED_1000;
210 		else if (bmcr & BMCR_SPEED100)
211 			phydev->speed = SPEED_100;
212 		else
213 			phydev->speed = SPEED_10;
214 
215 		phydev->pause = phydev->asym_pause = 0;
216 		linkmode_zero(phydev->lp_advertising);
217 	}
218 
219 	return 0;
220 }
221 
222 static int lxt973_probe(struct phy_device *phydev)
223 {
224 	int val = phy_read(phydev, MII_LXT973_PCR);
225 
226 	if (val & PCR_FIBER_SELECT) {
227 		/*
228 		 * If fiber is selected, then the only correct setting
229 		 * is 100Mbps, full duplex, and auto negotiation off.
230 		 */
231 		val = phy_read(phydev, MII_BMCR);
232 		val |= (BMCR_SPEED100 | BMCR_FULLDPLX);
233 		val &= ~BMCR_ANENABLE;
234 		phy_write(phydev, MII_BMCR, val);
235 		/* Remember that the port is in fiber mode. */
236 		phydev->priv = lxt973_probe;
237 	} else {
238 		phydev->priv = NULL;
239 	}
240 	return 0;
241 }
242 
243 static int lxt973_config_aneg(struct phy_device *phydev)
244 {
245 	/* Do nothing if port is in fiber mode. */
246 	return phydev->priv ? 0 : genphy_config_aneg(phydev);
247 }
248 
249 static struct phy_driver lxt97x_driver[] = {
250 {
251 	.phy_id		= 0x78100000,
252 	.name		= "LXT970",
253 	.phy_id_mask	= 0xfffffff0,
254 	.features	= PHY_BASIC_FEATURES,
255 	.config_init	= lxt970_config_init,
256 	.ack_interrupt	= lxt970_ack_interrupt,
257 	.config_intr	= lxt970_config_intr,
258 }, {
259 	.phy_id		= 0x001378e0,
260 	.name		= "LXT971",
261 	.phy_id_mask	= 0xfffffff0,
262 	.features	= PHY_BASIC_FEATURES,
263 	.ack_interrupt	= lxt971_ack_interrupt,
264 	.config_intr	= lxt971_config_intr,
265 }, {
266 	.phy_id		= 0x00137a10,
267 	.name		= "LXT973-A2",
268 	.phy_id_mask	= 0xffffffff,
269 	.features	= PHY_BASIC_FEATURES,
270 	.flags		= 0,
271 	.probe		= lxt973_probe,
272 	.config_aneg	= lxt973_config_aneg,
273 	.read_status	= lxt973a2_read_status,
274 }, {
275 	.phy_id		= 0x00137a10,
276 	.name		= "LXT973",
277 	.phy_id_mask	= 0xfffffff0,
278 	.features	= PHY_BASIC_FEATURES,
279 	.flags		= 0,
280 	.probe		= lxt973_probe,
281 	.config_aneg	= lxt973_config_aneg,
282 } };
283 
284 module_phy_driver(lxt97x_driver);
285 
286 static struct mdio_device_id __maybe_unused lxt_tbl[] = {
287 	{ 0x78100000, 0xfffffff0 },
288 	{ 0x001378e0, 0xfffffff0 },
289 	{ 0x00137a10, 0xfffffff0 },
290 	{ }
291 };
292 
293 MODULE_DEVICE_TABLE(mdio, lxt_tbl);
294