xref: /openbmc/linux/drivers/net/phy/at803x.c (revision a44e4f3a)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * drivers/net/phy/at803x.c
4  *
5  * Driver for Atheros 803x PHY
6  *
7  * Author: Matus Ujhelyi <ujhelyi.m@gmail.com>
8  */
9 
10 #include <linux/phy.h>
11 #include <linux/module.h>
12 #include <linux/string.h>
13 #include <linux/netdevice.h>
14 #include <linux/etherdevice.h>
15 #include <linux/of_gpio.h>
16 #include <linux/gpio/consumer.h>
17 
18 #define AT803X_SPECIFIC_STATUS			0x11
19 #define AT803X_SS_SPEED_MASK			(3 << 14)
20 #define AT803X_SS_SPEED_1000			(2 << 14)
21 #define AT803X_SS_SPEED_100			(1 << 14)
22 #define AT803X_SS_SPEED_10			(0 << 14)
23 #define AT803X_SS_DUPLEX			BIT(13)
24 #define AT803X_SS_SPEED_DUPLEX_RESOLVED		BIT(11)
25 #define AT803X_SS_MDIX				BIT(6)
26 
27 #define AT803X_INTR_ENABLE			0x12
28 #define AT803X_INTR_ENABLE_AUTONEG_ERR		BIT(15)
29 #define AT803X_INTR_ENABLE_SPEED_CHANGED	BIT(14)
30 #define AT803X_INTR_ENABLE_DUPLEX_CHANGED	BIT(13)
31 #define AT803X_INTR_ENABLE_PAGE_RECEIVED	BIT(12)
32 #define AT803X_INTR_ENABLE_LINK_FAIL		BIT(11)
33 #define AT803X_INTR_ENABLE_LINK_SUCCESS		BIT(10)
34 #define AT803X_INTR_ENABLE_WIRESPEED_DOWNGRADE	BIT(5)
35 #define AT803X_INTR_ENABLE_POLARITY_CHANGED	BIT(1)
36 #define AT803X_INTR_ENABLE_WOL			BIT(0)
37 
38 #define AT803X_INTR_STATUS			0x13
39 
40 #define AT803X_SMART_SPEED			0x14
41 #define AT803X_LED_CONTROL			0x18
42 
43 #define AT803X_DEVICE_ADDR			0x03
44 #define AT803X_LOC_MAC_ADDR_0_15_OFFSET		0x804C
45 #define AT803X_LOC_MAC_ADDR_16_31_OFFSET	0x804B
46 #define AT803X_LOC_MAC_ADDR_32_47_OFFSET	0x804A
47 #define AT803X_REG_CHIP_CONFIG			0x1f
48 #define AT803X_BT_BX_REG_SEL			0x8000
49 
50 #define AT803X_DEBUG_ADDR			0x1D
51 #define AT803X_DEBUG_DATA			0x1E
52 
53 #define AT803X_MODE_CFG_MASK			0x0F
54 #define AT803X_MODE_CFG_SGMII			0x01
55 
56 #define AT803X_PSSR			0x11	/*PHY-Specific Status Register*/
57 #define AT803X_PSSR_MR_AN_COMPLETE	0x0200
58 
59 #define AT803X_DEBUG_REG_0			0x00
60 #define AT803X_DEBUG_RX_CLK_DLY_EN		BIT(15)
61 
62 #define AT803X_DEBUG_REG_5			0x05
63 #define AT803X_DEBUG_TX_CLK_DLY_EN		BIT(8)
64 
65 #define ATH8030_PHY_ID 0x004dd076
66 #define ATH8031_PHY_ID 0x004dd074
67 #define ATH8035_PHY_ID 0x004dd072
68 #define AT803X_PHY_ID_MASK			0xffffffef
69 
70 MODULE_DESCRIPTION("Atheros 803x PHY driver");
71 MODULE_AUTHOR("Matus Ujhelyi");
72 MODULE_LICENSE("GPL");
73 
74 struct at803x_priv {
75 	bool phy_reset:1;
76 };
77 
78 struct at803x_context {
79 	u16 bmcr;
80 	u16 advertise;
81 	u16 control1000;
82 	u16 int_enable;
83 	u16 smart_speed;
84 	u16 led_control;
85 };
86 
87 static int at803x_debug_reg_read(struct phy_device *phydev, u16 reg)
88 {
89 	int ret;
90 
91 	ret = phy_write(phydev, AT803X_DEBUG_ADDR, reg);
92 	if (ret < 0)
93 		return ret;
94 
95 	return phy_read(phydev, AT803X_DEBUG_DATA);
96 }
97 
98 static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg,
99 				 u16 clear, u16 set)
100 {
101 	u16 val;
102 	int ret;
103 
104 	ret = at803x_debug_reg_read(phydev, reg);
105 	if (ret < 0)
106 		return ret;
107 
108 	val = ret & 0xffff;
109 	val &= ~clear;
110 	val |= set;
111 
112 	return phy_write(phydev, AT803X_DEBUG_DATA, val);
113 }
114 
115 static int at803x_enable_rx_delay(struct phy_device *phydev)
116 {
117 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
118 				     AT803X_DEBUG_RX_CLK_DLY_EN);
119 }
120 
121 static int at803x_enable_tx_delay(struct phy_device *phydev)
122 {
123 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0,
124 				     AT803X_DEBUG_TX_CLK_DLY_EN);
125 }
126 
127 static int at803x_disable_rx_delay(struct phy_device *phydev)
128 {
129 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
130 				     AT803X_DEBUG_RX_CLK_DLY_EN, 0);
131 }
132 
133 static int at803x_disable_tx_delay(struct phy_device *phydev)
134 {
135 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5,
136 				     AT803X_DEBUG_TX_CLK_DLY_EN, 0);
137 }
138 
139 /* save relevant PHY registers to private copy */
140 static void at803x_context_save(struct phy_device *phydev,
141 				struct at803x_context *context)
142 {
143 	context->bmcr = phy_read(phydev, MII_BMCR);
144 	context->advertise = phy_read(phydev, MII_ADVERTISE);
145 	context->control1000 = phy_read(phydev, MII_CTRL1000);
146 	context->int_enable = phy_read(phydev, AT803X_INTR_ENABLE);
147 	context->smart_speed = phy_read(phydev, AT803X_SMART_SPEED);
148 	context->led_control = phy_read(phydev, AT803X_LED_CONTROL);
149 }
150 
151 /* restore relevant PHY registers from private copy */
152 static void at803x_context_restore(struct phy_device *phydev,
153 				   const struct at803x_context *context)
154 {
155 	phy_write(phydev, MII_BMCR, context->bmcr);
156 	phy_write(phydev, MII_ADVERTISE, context->advertise);
157 	phy_write(phydev, MII_CTRL1000, context->control1000);
158 	phy_write(phydev, AT803X_INTR_ENABLE, context->int_enable);
159 	phy_write(phydev, AT803X_SMART_SPEED, context->smart_speed);
160 	phy_write(phydev, AT803X_LED_CONTROL, context->led_control);
161 }
162 
163 static int at803x_set_wol(struct phy_device *phydev,
164 			  struct ethtool_wolinfo *wol)
165 {
166 	struct net_device *ndev = phydev->attached_dev;
167 	const u8 *mac;
168 	int ret;
169 	u32 value;
170 	unsigned int i, offsets[] = {
171 		AT803X_LOC_MAC_ADDR_32_47_OFFSET,
172 		AT803X_LOC_MAC_ADDR_16_31_OFFSET,
173 		AT803X_LOC_MAC_ADDR_0_15_OFFSET,
174 	};
175 
176 	if (!ndev)
177 		return -ENODEV;
178 
179 	if (wol->wolopts & WAKE_MAGIC) {
180 		mac = (const u8 *) ndev->dev_addr;
181 
182 		if (!is_valid_ether_addr(mac))
183 			return -EINVAL;
184 
185 		for (i = 0; i < 3; i++)
186 			phy_write_mmd(phydev, AT803X_DEVICE_ADDR, offsets[i],
187 				      mac[(i * 2) + 1] | (mac[(i * 2)] << 8));
188 
189 		value = phy_read(phydev, AT803X_INTR_ENABLE);
190 		value |= AT803X_INTR_ENABLE_WOL;
191 		ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
192 		if (ret)
193 			return ret;
194 		value = phy_read(phydev, AT803X_INTR_STATUS);
195 	} else {
196 		value = phy_read(phydev, AT803X_INTR_ENABLE);
197 		value &= (~AT803X_INTR_ENABLE_WOL);
198 		ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
199 		if (ret)
200 			return ret;
201 		value = phy_read(phydev, AT803X_INTR_STATUS);
202 	}
203 
204 	return ret;
205 }
206 
207 static void at803x_get_wol(struct phy_device *phydev,
208 			   struct ethtool_wolinfo *wol)
209 {
210 	u32 value;
211 
212 	wol->supported = WAKE_MAGIC;
213 	wol->wolopts = 0;
214 
215 	value = phy_read(phydev, AT803X_INTR_ENABLE);
216 	if (value & AT803X_INTR_ENABLE_WOL)
217 		wol->wolopts |= WAKE_MAGIC;
218 }
219 
220 static int at803x_suspend(struct phy_device *phydev)
221 {
222 	int value;
223 	int wol_enabled;
224 
225 	value = phy_read(phydev, AT803X_INTR_ENABLE);
226 	wol_enabled = value & AT803X_INTR_ENABLE_WOL;
227 
228 	if (wol_enabled)
229 		value = BMCR_ISOLATE;
230 	else
231 		value = BMCR_PDOWN;
232 
233 	phy_modify(phydev, MII_BMCR, 0, value);
234 
235 	return 0;
236 }
237 
238 static int at803x_resume(struct phy_device *phydev)
239 {
240 	return phy_modify(phydev, MII_BMCR, BMCR_PDOWN | BMCR_ISOLATE, 0);
241 }
242 
243 static int at803x_probe(struct phy_device *phydev)
244 {
245 	struct device *dev = &phydev->mdio.dev;
246 	struct at803x_priv *priv;
247 
248 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
249 	if (!priv)
250 		return -ENOMEM;
251 
252 	phydev->priv = priv;
253 
254 	return 0;
255 }
256 
257 static int at803x_config_init(struct phy_device *phydev)
258 {
259 	int ret;
260 
261 	/* The RX and TX delay default is:
262 	 *   after HW reset: RX delay enabled and TX delay disabled
263 	 *   after SW reset: RX delay enabled, while TX delay retains the
264 	 *   value before reset.
265 	 */
266 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
267 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID)
268 		ret = at803x_enable_rx_delay(phydev);
269 	else
270 		ret = at803x_disable_rx_delay(phydev);
271 	if (ret < 0)
272 		return ret;
273 
274 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
275 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
276 		ret = at803x_enable_tx_delay(phydev);
277 	else
278 		ret = at803x_disable_tx_delay(phydev);
279 
280 	return ret;
281 }
282 
283 static int at803x_ack_interrupt(struct phy_device *phydev)
284 {
285 	int err;
286 
287 	err = phy_read(phydev, AT803X_INTR_STATUS);
288 
289 	return (err < 0) ? err : 0;
290 }
291 
292 static int at803x_config_intr(struct phy_device *phydev)
293 {
294 	int err;
295 	int value;
296 
297 	value = phy_read(phydev, AT803X_INTR_ENABLE);
298 
299 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
300 		value |= AT803X_INTR_ENABLE_AUTONEG_ERR;
301 		value |= AT803X_INTR_ENABLE_SPEED_CHANGED;
302 		value |= AT803X_INTR_ENABLE_DUPLEX_CHANGED;
303 		value |= AT803X_INTR_ENABLE_LINK_FAIL;
304 		value |= AT803X_INTR_ENABLE_LINK_SUCCESS;
305 
306 		err = phy_write(phydev, AT803X_INTR_ENABLE, value);
307 	}
308 	else
309 		err = phy_write(phydev, AT803X_INTR_ENABLE, 0);
310 
311 	return err;
312 }
313 
314 static void at803x_link_change_notify(struct phy_device *phydev)
315 {
316 	/*
317 	 * Conduct a hardware reset for AT8030 every time a link loss is
318 	 * signalled. This is necessary to circumvent a hardware bug that
319 	 * occurs when the cable is unplugged while TX packets are pending
320 	 * in the FIFO. In such cases, the FIFO enters an error mode it
321 	 * cannot recover from by software.
322 	 */
323 	if (phydev->state == PHY_NOLINK && phydev->mdio.reset_gpio) {
324 		struct at803x_context context;
325 
326 		at803x_context_save(phydev, &context);
327 
328 		phy_device_reset(phydev, 1);
329 		msleep(1);
330 		phy_device_reset(phydev, 0);
331 		msleep(1);
332 
333 		at803x_context_restore(phydev, &context);
334 
335 		phydev_dbg(phydev, "%s(): phy was reset\n", __func__);
336 	}
337 }
338 
339 static int at803x_aneg_done(struct phy_device *phydev)
340 {
341 	int ccr;
342 
343 	int aneg_done = genphy_aneg_done(phydev);
344 	if (aneg_done != BMSR_ANEGCOMPLETE)
345 		return aneg_done;
346 
347 	/*
348 	 * in SGMII mode, if copper side autoneg is successful,
349 	 * also check SGMII side autoneg result
350 	 */
351 	ccr = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
352 	if ((ccr & AT803X_MODE_CFG_MASK) != AT803X_MODE_CFG_SGMII)
353 		return aneg_done;
354 
355 	/* switch to SGMII/fiber page */
356 	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr & ~AT803X_BT_BX_REG_SEL);
357 
358 	/* check if the SGMII link is OK. */
359 	if (!(phy_read(phydev, AT803X_PSSR) & AT803X_PSSR_MR_AN_COMPLETE)) {
360 		phydev_warn(phydev, "803x_aneg_done: SGMII link is not ok\n");
361 		aneg_done = 0;
362 	}
363 	/* switch back to copper page */
364 	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr | AT803X_BT_BX_REG_SEL);
365 
366 	return aneg_done;
367 }
368 
369 static int at803x_read_status(struct phy_device *phydev)
370 {
371 	int ss, err, old_link = phydev->link;
372 
373 	/* Update the link, but return if there was an error */
374 	err = genphy_update_link(phydev);
375 	if (err)
376 		return err;
377 
378 	/* why bother the PHY if nothing can have changed */
379 	if (phydev->autoneg == AUTONEG_ENABLE && old_link && phydev->link)
380 		return 0;
381 
382 	phydev->speed = SPEED_UNKNOWN;
383 	phydev->duplex = DUPLEX_UNKNOWN;
384 	phydev->pause = 0;
385 	phydev->asym_pause = 0;
386 
387 	err = genphy_read_lpa(phydev);
388 	if (err < 0)
389 		return err;
390 
391 	/* Read the AT8035 PHY-Specific Status register, which indicates the
392 	 * speed and duplex that the PHY is actually using, irrespective of
393 	 * whether we are in autoneg mode or not.
394 	 */
395 	ss = phy_read(phydev, AT803X_SPECIFIC_STATUS);
396 	if (ss < 0)
397 		return ss;
398 
399 	if (ss & AT803X_SS_SPEED_DUPLEX_RESOLVED) {
400 		switch (ss & AT803X_SS_SPEED_MASK) {
401 		case AT803X_SS_SPEED_10:
402 			phydev->speed = SPEED_10;
403 			break;
404 		case AT803X_SS_SPEED_100:
405 			phydev->speed = SPEED_100;
406 			break;
407 		case AT803X_SS_SPEED_1000:
408 			phydev->speed = SPEED_1000;
409 			break;
410 		}
411 		if (ss & AT803X_SS_DUPLEX)
412 			phydev->duplex = DUPLEX_FULL;
413 		else
414 			phydev->duplex = DUPLEX_HALF;
415 		if (ss & AT803X_SS_MDIX)
416 			phydev->mdix = ETH_TP_MDI_X;
417 		else
418 			phydev->mdix = ETH_TP_MDI;
419 	}
420 
421 	if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete)
422 		phy_resolve_aneg_pause(phydev);
423 
424 	return 0;
425 }
426 
427 static struct phy_driver at803x_driver[] = {
428 {
429 	/* ATHEROS 8035 */
430 	.phy_id			= ATH8035_PHY_ID,
431 	.name			= "Atheros 8035 ethernet",
432 	.phy_id_mask		= AT803X_PHY_ID_MASK,
433 	.probe			= at803x_probe,
434 	.config_init		= at803x_config_init,
435 	.set_wol		= at803x_set_wol,
436 	.get_wol		= at803x_get_wol,
437 	.suspend		= at803x_suspend,
438 	.resume			= at803x_resume,
439 	/* PHY_GBIT_FEATURES */
440 	.read_status		= at803x_read_status,
441 	.ack_interrupt		= at803x_ack_interrupt,
442 	.config_intr		= at803x_config_intr,
443 }, {
444 	/* ATHEROS 8030 */
445 	.phy_id			= ATH8030_PHY_ID,
446 	.name			= "Atheros 8030 ethernet",
447 	.phy_id_mask		= AT803X_PHY_ID_MASK,
448 	.probe			= at803x_probe,
449 	.config_init		= at803x_config_init,
450 	.link_change_notify	= at803x_link_change_notify,
451 	.set_wol		= at803x_set_wol,
452 	.get_wol		= at803x_get_wol,
453 	.suspend		= at803x_suspend,
454 	.resume			= at803x_resume,
455 	/* PHY_BASIC_FEATURES */
456 	.ack_interrupt		= at803x_ack_interrupt,
457 	.config_intr		= at803x_config_intr,
458 }, {
459 	/* ATHEROS 8031 */
460 	.phy_id			= ATH8031_PHY_ID,
461 	.name			= "Atheros 8031 ethernet",
462 	.phy_id_mask		= AT803X_PHY_ID_MASK,
463 	.probe			= at803x_probe,
464 	.config_init		= at803x_config_init,
465 	.set_wol		= at803x_set_wol,
466 	.get_wol		= at803x_get_wol,
467 	.suspend		= at803x_suspend,
468 	.resume			= at803x_resume,
469 	/* PHY_GBIT_FEATURES */
470 	.read_status		= at803x_read_status,
471 	.aneg_done		= at803x_aneg_done,
472 	.ack_interrupt		= &at803x_ack_interrupt,
473 	.config_intr		= &at803x_config_intr,
474 } };
475 
476 module_phy_driver(at803x_driver);
477 
478 static struct mdio_device_id __maybe_unused atheros_tbl[] = {
479 	{ ATH8030_PHY_ID, AT803X_PHY_ID_MASK },
480 	{ ATH8031_PHY_ID, AT803X_PHY_ID_MASK },
481 	{ ATH8035_PHY_ID, AT803X_PHY_ID_MASK },
482 	{ }
483 };
484 
485 MODULE_DEVICE_TABLE(mdio, atheros_tbl);
486