xref: /openbmc/linux/drivers/net/phy/at803x.c (revision 68198dca)
1 /*
2  * drivers/net/phy/at803x.c
3  *
4  * Driver for Atheros 803x PHY
5  *
6  * Author: Matus Ujhelyi <ujhelyi.m@gmail.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  */
13 
14 #include <linux/phy.h>
15 #include <linux/module.h>
16 #include <linux/string.h>
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/of_gpio.h>
20 #include <linux/gpio/consumer.h>
21 
22 #define AT803X_INTR_ENABLE			0x12
23 #define AT803X_INTR_ENABLE_AUTONEG_ERR		BIT(15)
24 #define AT803X_INTR_ENABLE_SPEED_CHANGED	BIT(14)
25 #define AT803X_INTR_ENABLE_DUPLEX_CHANGED	BIT(13)
26 #define AT803X_INTR_ENABLE_PAGE_RECEIVED	BIT(12)
27 #define AT803X_INTR_ENABLE_LINK_FAIL		BIT(11)
28 #define AT803X_INTR_ENABLE_LINK_SUCCESS		BIT(10)
29 #define AT803X_INTR_ENABLE_WIRESPEED_DOWNGRADE	BIT(5)
30 #define AT803X_INTR_ENABLE_POLARITY_CHANGED	BIT(1)
31 #define AT803X_INTR_ENABLE_WOL			BIT(0)
32 
33 #define AT803X_INTR_STATUS			0x13
34 
35 #define AT803X_SMART_SPEED			0x14
36 #define AT803X_LED_CONTROL			0x18
37 
38 #define AT803X_DEVICE_ADDR			0x03
39 #define AT803X_LOC_MAC_ADDR_0_15_OFFSET		0x804C
40 #define AT803X_LOC_MAC_ADDR_16_31_OFFSET	0x804B
41 #define AT803X_LOC_MAC_ADDR_32_47_OFFSET	0x804A
42 #define AT803X_MMD_ACCESS_CONTROL		0x0D
43 #define AT803X_MMD_ACCESS_CONTROL_DATA		0x0E
44 #define AT803X_FUNC_DATA			0x4003
45 #define AT803X_REG_CHIP_CONFIG			0x1f
46 #define AT803X_BT_BX_REG_SEL			0x8000
47 
48 #define AT803X_DEBUG_ADDR			0x1D
49 #define AT803X_DEBUG_DATA			0x1E
50 
51 #define AT803X_MODE_CFG_MASK			0x0F
52 #define AT803X_MODE_CFG_SGMII			0x01
53 
54 #define AT803X_PSSR			0x11	/*PHY-Specific Status Register*/
55 #define AT803X_PSSR_MR_AN_COMPLETE	0x0200
56 
57 #define AT803X_DEBUG_REG_0			0x00
58 #define AT803X_DEBUG_RX_CLK_DLY_EN		BIT(15)
59 
60 #define AT803X_DEBUG_REG_5			0x05
61 #define AT803X_DEBUG_TX_CLK_DLY_EN		BIT(8)
62 
63 #define ATH8030_PHY_ID 0x004dd076
64 #define ATH8031_PHY_ID 0x004dd074
65 #define ATH8035_PHY_ID 0x004dd072
66 #define AT803X_PHY_ID_MASK			0xffffffef
67 
68 MODULE_DESCRIPTION("Atheros 803x PHY driver");
69 MODULE_AUTHOR("Matus Ujhelyi");
70 MODULE_LICENSE("GPL");
71 
72 struct at803x_priv {
73 	bool phy_reset:1;
74 	struct gpio_desc *gpiod_reset;
75 };
76 
77 struct at803x_context {
78 	u16 bmcr;
79 	u16 advertise;
80 	u16 control1000;
81 	u16 int_enable;
82 	u16 smart_speed;
83 	u16 led_control;
84 };
85 
86 static int at803x_debug_reg_read(struct phy_device *phydev, u16 reg)
87 {
88 	int ret;
89 
90 	ret = phy_write(phydev, AT803X_DEBUG_ADDR, reg);
91 	if (ret < 0)
92 		return ret;
93 
94 	return phy_read(phydev, AT803X_DEBUG_DATA);
95 }
96 
97 static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg,
98 				 u16 clear, u16 set)
99 {
100 	u16 val;
101 	int ret;
102 
103 	ret = at803x_debug_reg_read(phydev, reg);
104 	if (ret < 0)
105 		return ret;
106 
107 	val = ret & 0xffff;
108 	val &= ~clear;
109 	val |= set;
110 
111 	return phy_write(phydev, AT803X_DEBUG_DATA, val);
112 }
113 
114 static inline int at803x_enable_rx_delay(struct phy_device *phydev)
115 {
116 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
117 					AT803X_DEBUG_RX_CLK_DLY_EN);
118 }
119 
120 static inline int at803x_enable_tx_delay(struct phy_device *phydev)
121 {
122 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0,
123 					AT803X_DEBUG_TX_CLK_DLY_EN);
124 }
125 
126 /* save relevant PHY registers to private copy */
127 static void at803x_context_save(struct phy_device *phydev,
128 				struct at803x_context *context)
129 {
130 	context->bmcr = phy_read(phydev, MII_BMCR);
131 	context->advertise = phy_read(phydev, MII_ADVERTISE);
132 	context->control1000 = phy_read(phydev, MII_CTRL1000);
133 	context->int_enable = phy_read(phydev, AT803X_INTR_ENABLE);
134 	context->smart_speed = phy_read(phydev, AT803X_SMART_SPEED);
135 	context->led_control = phy_read(phydev, AT803X_LED_CONTROL);
136 }
137 
138 /* restore relevant PHY registers from private copy */
139 static void at803x_context_restore(struct phy_device *phydev,
140 				   const struct at803x_context *context)
141 {
142 	phy_write(phydev, MII_BMCR, context->bmcr);
143 	phy_write(phydev, MII_ADVERTISE, context->advertise);
144 	phy_write(phydev, MII_CTRL1000, context->control1000);
145 	phy_write(phydev, AT803X_INTR_ENABLE, context->int_enable);
146 	phy_write(phydev, AT803X_SMART_SPEED, context->smart_speed);
147 	phy_write(phydev, AT803X_LED_CONTROL, context->led_control);
148 }
149 
150 static int at803x_set_wol(struct phy_device *phydev,
151 			  struct ethtool_wolinfo *wol)
152 {
153 	struct net_device *ndev = phydev->attached_dev;
154 	const u8 *mac;
155 	int ret;
156 	u32 value;
157 	unsigned int i, offsets[] = {
158 		AT803X_LOC_MAC_ADDR_32_47_OFFSET,
159 		AT803X_LOC_MAC_ADDR_16_31_OFFSET,
160 		AT803X_LOC_MAC_ADDR_0_15_OFFSET,
161 	};
162 
163 	if (!ndev)
164 		return -ENODEV;
165 
166 	if (wol->wolopts & WAKE_MAGIC) {
167 		mac = (const u8 *) ndev->dev_addr;
168 
169 		if (!is_valid_ether_addr(mac))
170 			return -EINVAL;
171 
172 		for (i = 0; i < 3; i++) {
173 			phy_write(phydev, AT803X_MMD_ACCESS_CONTROL,
174 				  AT803X_DEVICE_ADDR);
175 			phy_write(phydev, AT803X_MMD_ACCESS_CONTROL_DATA,
176 				  offsets[i]);
177 			phy_write(phydev, AT803X_MMD_ACCESS_CONTROL,
178 				  AT803X_FUNC_DATA);
179 			phy_write(phydev, AT803X_MMD_ACCESS_CONTROL_DATA,
180 				  mac[(i * 2) + 1] | (mac[(i * 2)] << 8));
181 		}
182 
183 		value = phy_read(phydev, AT803X_INTR_ENABLE);
184 		value |= AT803X_INTR_ENABLE_WOL;
185 		ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
186 		if (ret)
187 			return ret;
188 		value = phy_read(phydev, AT803X_INTR_STATUS);
189 	} else {
190 		value = phy_read(phydev, AT803X_INTR_ENABLE);
191 		value &= (~AT803X_INTR_ENABLE_WOL);
192 		ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
193 		if (ret)
194 			return ret;
195 		value = phy_read(phydev, AT803X_INTR_STATUS);
196 	}
197 
198 	return ret;
199 }
200 
201 static void at803x_get_wol(struct phy_device *phydev,
202 			   struct ethtool_wolinfo *wol)
203 {
204 	u32 value;
205 
206 	wol->supported = WAKE_MAGIC;
207 	wol->wolopts = 0;
208 
209 	value = phy_read(phydev, AT803X_INTR_ENABLE);
210 	if (value & AT803X_INTR_ENABLE_WOL)
211 		wol->wolopts |= WAKE_MAGIC;
212 }
213 
214 static int at803x_suspend(struct phy_device *phydev)
215 {
216 	int value;
217 	int wol_enabled;
218 
219 	mutex_lock(&phydev->lock);
220 
221 	value = phy_read(phydev, AT803X_INTR_ENABLE);
222 	wol_enabled = value & AT803X_INTR_ENABLE_WOL;
223 
224 	value = phy_read(phydev, MII_BMCR);
225 
226 	if (wol_enabled)
227 		value |= BMCR_ISOLATE;
228 	else
229 		value |= BMCR_PDOWN;
230 
231 	phy_write(phydev, MII_BMCR, value);
232 
233 	mutex_unlock(&phydev->lock);
234 
235 	return 0;
236 }
237 
238 static int at803x_resume(struct phy_device *phydev)
239 {
240 	int value;
241 
242 	value = phy_read(phydev, MII_BMCR);
243 	value &= ~(BMCR_PDOWN | BMCR_ISOLATE);
244 	phy_write(phydev, MII_BMCR, value);
245 
246 	return 0;
247 }
248 
249 static int at803x_probe(struct phy_device *phydev)
250 {
251 	struct device *dev = &phydev->mdio.dev;
252 	struct at803x_priv *priv;
253 	struct gpio_desc *gpiod_reset;
254 
255 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
256 	if (!priv)
257 		return -ENOMEM;
258 
259 	if (phydev->drv->phy_id != ATH8030_PHY_ID)
260 		goto does_not_require_reset_workaround;
261 
262 	gpiod_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
263 	if (IS_ERR(gpiod_reset))
264 		return PTR_ERR(gpiod_reset);
265 
266 	priv->gpiod_reset = gpiod_reset;
267 
268 does_not_require_reset_workaround:
269 	phydev->priv = priv;
270 
271 	return 0;
272 }
273 
274 static int at803x_config_init(struct phy_device *phydev)
275 {
276 	int ret;
277 
278 	ret = genphy_config_init(phydev);
279 	if (ret < 0)
280 		return ret;
281 
282 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
283 			phydev->interface == PHY_INTERFACE_MODE_RGMII_ID) {
284 		ret = at803x_enable_rx_delay(phydev);
285 		if (ret < 0)
286 			return ret;
287 	}
288 
289 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID ||
290 			phydev->interface == PHY_INTERFACE_MODE_RGMII_ID) {
291 		ret = at803x_enable_tx_delay(phydev);
292 		if (ret < 0)
293 			return ret;
294 	}
295 
296 	return 0;
297 }
298 
299 static int at803x_ack_interrupt(struct phy_device *phydev)
300 {
301 	int err;
302 
303 	err = phy_read(phydev, AT803X_INTR_STATUS);
304 
305 	return (err < 0) ? err : 0;
306 }
307 
308 static int at803x_config_intr(struct phy_device *phydev)
309 {
310 	int err;
311 	int value;
312 
313 	value = phy_read(phydev, AT803X_INTR_ENABLE);
314 
315 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
316 		value |= AT803X_INTR_ENABLE_AUTONEG_ERR;
317 		value |= AT803X_INTR_ENABLE_SPEED_CHANGED;
318 		value |= AT803X_INTR_ENABLE_DUPLEX_CHANGED;
319 		value |= AT803X_INTR_ENABLE_LINK_FAIL;
320 		value |= AT803X_INTR_ENABLE_LINK_SUCCESS;
321 
322 		err = phy_write(phydev, AT803X_INTR_ENABLE, value);
323 	}
324 	else
325 		err = phy_write(phydev, AT803X_INTR_ENABLE, 0);
326 
327 	return err;
328 }
329 
330 static void at803x_link_change_notify(struct phy_device *phydev)
331 {
332 	struct at803x_priv *priv = phydev->priv;
333 
334 	/*
335 	 * Conduct a hardware reset for AT8030 every time a link loss is
336 	 * signalled. This is necessary to circumvent a hardware bug that
337 	 * occurs when the cable is unplugged while TX packets are pending
338 	 * in the FIFO. In such cases, the FIFO enters an error mode it
339 	 * cannot recover from by software.
340 	 */
341 	if (phydev->state == PHY_NOLINK) {
342 		if (priv->gpiod_reset && !priv->phy_reset) {
343 			struct at803x_context context;
344 
345 			at803x_context_save(phydev, &context);
346 
347 			gpiod_set_value(priv->gpiod_reset, 1);
348 			msleep(1);
349 			gpiod_set_value(priv->gpiod_reset, 0);
350 			msleep(1);
351 
352 			at803x_context_restore(phydev, &context);
353 
354 			phydev_dbg(phydev, "%s(): phy was reset\n",
355 				   __func__);
356 			priv->phy_reset = true;
357 		}
358 	} else {
359 		priv->phy_reset = false;
360 	}
361 }
362 
363 static int at803x_aneg_done(struct phy_device *phydev)
364 {
365 	int ccr;
366 
367 	int aneg_done = genphy_aneg_done(phydev);
368 	if (aneg_done != BMSR_ANEGCOMPLETE)
369 		return aneg_done;
370 
371 	/*
372 	 * in SGMII mode, if copper side autoneg is successful,
373 	 * also check SGMII side autoneg result
374 	 */
375 	ccr = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
376 	if ((ccr & AT803X_MODE_CFG_MASK) != AT803X_MODE_CFG_SGMII)
377 		return aneg_done;
378 
379 	/* switch to SGMII/fiber page */
380 	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr & ~AT803X_BT_BX_REG_SEL);
381 
382 	/* check if the SGMII link is OK. */
383 	if (!(phy_read(phydev, AT803X_PSSR) & AT803X_PSSR_MR_AN_COMPLETE)) {
384 		pr_warn("803x_aneg_done: SGMII link is not ok\n");
385 		aneg_done = 0;
386 	}
387 	/* switch back to copper page */
388 	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr | AT803X_BT_BX_REG_SEL);
389 
390 	return aneg_done;
391 }
392 
393 static struct phy_driver at803x_driver[] = {
394 {
395 	/* ATHEROS 8035 */
396 	.phy_id			= ATH8035_PHY_ID,
397 	.name			= "Atheros 8035 ethernet",
398 	.phy_id_mask		= AT803X_PHY_ID_MASK,
399 	.probe			= at803x_probe,
400 	.config_init		= at803x_config_init,
401 	.set_wol		= at803x_set_wol,
402 	.get_wol		= at803x_get_wol,
403 	.suspend		= at803x_suspend,
404 	.resume			= at803x_resume,
405 	.features		= PHY_GBIT_FEATURES,
406 	.flags			= PHY_HAS_INTERRUPT,
407 	.config_aneg		= genphy_config_aneg,
408 	.read_status		= genphy_read_status,
409 	.ack_interrupt		= at803x_ack_interrupt,
410 	.config_intr		= at803x_config_intr,
411 }, {
412 	/* ATHEROS 8030 */
413 	.phy_id			= ATH8030_PHY_ID,
414 	.name			= "Atheros 8030 ethernet",
415 	.phy_id_mask		= AT803X_PHY_ID_MASK,
416 	.probe			= at803x_probe,
417 	.config_init		= at803x_config_init,
418 	.link_change_notify	= at803x_link_change_notify,
419 	.set_wol		= at803x_set_wol,
420 	.get_wol		= at803x_get_wol,
421 	.suspend		= at803x_suspend,
422 	.resume			= at803x_resume,
423 	.features		= PHY_BASIC_FEATURES,
424 	.flags			= PHY_HAS_INTERRUPT,
425 	.config_aneg		= genphy_config_aneg,
426 	.read_status		= genphy_read_status,
427 	.ack_interrupt		= at803x_ack_interrupt,
428 	.config_intr		= at803x_config_intr,
429 }, {
430 	/* ATHEROS 8031 */
431 	.phy_id			= ATH8031_PHY_ID,
432 	.name			= "Atheros 8031 ethernet",
433 	.phy_id_mask		= AT803X_PHY_ID_MASK,
434 	.probe			= at803x_probe,
435 	.config_init		= at803x_config_init,
436 	.set_wol		= at803x_set_wol,
437 	.get_wol		= at803x_get_wol,
438 	.suspend		= at803x_suspend,
439 	.resume			= at803x_resume,
440 	.features		= PHY_GBIT_FEATURES,
441 	.flags			= PHY_HAS_INTERRUPT,
442 	.config_aneg		= genphy_config_aneg,
443 	.read_status		= genphy_read_status,
444 	.aneg_done		= at803x_aneg_done,
445 	.ack_interrupt		= &at803x_ack_interrupt,
446 	.config_intr		= &at803x_config_intr,
447 } };
448 
449 module_phy_driver(at803x_driver);
450 
451 static struct mdio_device_id __maybe_unused atheros_tbl[] = {
452 	{ ATH8030_PHY_ID, AT803X_PHY_ID_MASK },
453 	{ ATH8031_PHY_ID, AT803X_PHY_ID_MASK },
454 	{ ATH8035_PHY_ID, AT803X_PHY_ID_MASK },
455 	{ }
456 };
457 
458 MODULE_DEVICE_TABLE(mdio, atheros_tbl);
459