xref: /openbmc/linux/drivers/net/phy/at803x.c (revision b1a3e75e)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * drivers/net/phy/at803x.c
4  *
5  * Driver for Qualcomm Atheros AR803x 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/ethtool_netlink.h>
16 #include <linux/of_gpio.h>
17 #include <linux/bitfield.h>
18 #include <linux/gpio/consumer.h>
19 #include <linux/regulator/of_regulator.h>
20 #include <linux/regulator/driver.h>
21 #include <linux/regulator/consumer.h>
22 #include <dt-bindings/net/qca-ar803x.h>
23 
24 #define AT803X_SPECIFIC_FUNCTION_CONTROL	0x10
25 #define AT803X_SFC_ASSERT_CRS			BIT(11)
26 #define AT803X_SFC_FORCE_LINK			BIT(10)
27 #define AT803X_SFC_MDI_CROSSOVER_MODE_M		GENMASK(6, 5)
28 #define AT803X_SFC_AUTOMATIC_CROSSOVER		0x3
29 #define AT803X_SFC_MANUAL_MDIX			0x1
30 #define AT803X_SFC_MANUAL_MDI			0x0
31 #define AT803X_SFC_SQE_TEST			BIT(2)
32 #define AT803X_SFC_POLARITY_REVERSAL		BIT(1)
33 #define AT803X_SFC_DISABLE_JABBER		BIT(0)
34 
35 #define AT803X_SPECIFIC_STATUS			0x11
36 #define AT803X_SS_SPEED_MASK			(3 << 14)
37 #define AT803X_SS_SPEED_1000			(2 << 14)
38 #define AT803X_SS_SPEED_100			(1 << 14)
39 #define AT803X_SS_SPEED_10			(0 << 14)
40 #define AT803X_SS_DUPLEX			BIT(13)
41 #define AT803X_SS_SPEED_DUPLEX_RESOLVED		BIT(11)
42 #define AT803X_SS_MDIX				BIT(6)
43 
44 #define AT803X_INTR_ENABLE			0x12
45 #define AT803X_INTR_ENABLE_AUTONEG_ERR		BIT(15)
46 #define AT803X_INTR_ENABLE_SPEED_CHANGED	BIT(14)
47 #define AT803X_INTR_ENABLE_DUPLEX_CHANGED	BIT(13)
48 #define AT803X_INTR_ENABLE_PAGE_RECEIVED	BIT(12)
49 #define AT803X_INTR_ENABLE_LINK_FAIL		BIT(11)
50 #define AT803X_INTR_ENABLE_LINK_SUCCESS		BIT(10)
51 #define AT803X_INTR_ENABLE_WIRESPEED_DOWNGRADE	BIT(5)
52 #define AT803X_INTR_ENABLE_POLARITY_CHANGED	BIT(1)
53 #define AT803X_INTR_ENABLE_WOL			BIT(0)
54 
55 #define AT803X_INTR_STATUS			0x13
56 
57 #define AT803X_SMART_SPEED			0x14
58 #define AT803X_SMART_SPEED_ENABLE		BIT(5)
59 #define AT803X_SMART_SPEED_RETRY_LIMIT_MASK	GENMASK(4, 2)
60 #define AT803X_SMART_SPEED_BYPASS_TIMER		BIT(1)
61 #define AT803X_CDT				0x16
62 #define AT803X_CDT_MDI_PAIR_MASK		GENMASK(9, 8)
63 #define AT803X_CDT_ENABLE_TEST			BIT(0)
64 #define AT803X_CDT_STATUS			0x1c
65 #define AT803X_CDT_STATUS_STAT_NORMAL		0
66 #define AT803X_CDT_STATUS_STAT_SHORT		1
67 #define AT803X_CDT_STATUS_STAT_OPEN		2
68 #define AT803X_CDT_STATUS_STAT_FAIL		3
69 #define AT803X_CDT_STATUS_STAT_MASK		GENMASK(9, 8)
70 #define AT803X_CDT_STATUS_DELTA_TIME_MASK	GENMASK(7, 0)
71 #define AT803X_LED_CONTROL			0x18
72 
73 #define AT803X_DEVICE_ADDR			0x03
74 #define AT803X_LOC_MAC_ADDR_0_15_OFFSET		0x804C
75 #define AT803X_LOC_MAC_ADDR_16_31_OFFSET	0x804B
76 #define AT803X_LOC_MAC_ADDR_32_47_OFFSET	0x804A
77 #define AT803X_REG_CHIP_CONFIG			0x1f
78 #define AT803X_BT_BX_REG_SEL			0x8000
79 
80 #define AT803X_DEBUG_ADDR			0x1D
81 #define AT803X_DEBUG_DATA			0x1E
82 
83 #define AT803X_MODE_CFG_MASK			0x0F
84 #define AT803X_MODE_CFG_SGMII			0x01
85 
86 #define AT803X_PSSR			0x11	/*PHY-Specific Status Register*/
87 #define AT803X_PSSR_MR_AN_COMPLETE	0x0200
88 
89 #define AT803X_DEBUG_REG_0			0x00
90 #define AT803X_DEBUG_RX_CLK_DLY_EN		BIT(15)
91 
92 #define AT803X_DEBUG_REG_5			0x05
93 #define AT803X_DEBUG_TX_CLK_DLY_EN		BIT(8)
94 
95 #define AT803X_DEBUG_REG_1F			0x1F
96 #define AT803X_DEBUG_PLL_ON			BIT(2)
97 #define AT803X_DEBUG_RGMII_1V8			BIT(3)
98 
99 /* AT803x supports either the XTAL input pad, an internal PLL or the
100  * DSP as clock reference for the clock output pad. The XTAL reference
101  * is only used for 25 MHz output, all other frequencies need the PLL.
102  * The DSP as a clock reference is used in synchronous ethernet
103  * applications.
104  *
105  * By default the PLL is only enabled if there is a link. Otherwise
106  * the PHY will go into low power state and disabled the PLL. You can
107  * set the PLL_ON bit (see debug register 0x1f) to keep the PLL always
108  * enabled.
109  */
110 #define AT803X_MMD7_CLK25M			0x8016
111 #define AT803X_CLK_OUT_MASK			GENMASK(4, 2)
112 #define AT803X_CLK_OUT_25MHZ_XTAL		0
113 #define AT803X_CLK_OUT_25MHZ_DSP		1
114 #define AT803X_CLK_OUT_50MHZ_PLL		2
115 #define AT803X_CLK_OUT_50MHZ_DSP		3
116 #define AT803X_CLK_OUT_62_5MHZ_PLL		4
117 #define AT803X_CLK_OUT_62_5MHZ_DSP		5
118 #define AT803X_CLK_OUT_125MHZ_PLL		6
119 #define AT803X_CLK_OUT_125MHZ_DSP		7
120 
121 /* The AR8035 has another mask which is compatible with the AR8031/AR8033 mask
122  * but doesn't support choosing between XTAL/PLL and DSP.
123  */
124 #define AT8035_CLK_OUT_MASK			GENMASK(4, 3)
125 
126 #define AT803X_CLK_OUT_STRENGTH_MASK		GENMASK(8, 7)
127 #define AT803X_CLK_OUT_STRENGTH_FULL		0
128 #define AT803X_CLK_OUT_STRENGTH_HALF		1
129 #define AT803X_CLK_OUT_STRENGTH_QUARTER		2
130 
131 #define AT803X_DEFAULT_DOWNSHIFT 5
132 #define AT803X_MIN_DOWNSHIFT 2
133 #define AT803X_MAX_DOWNSHIFT 9
134 
135 #define ATH9331_PHY_ID 0x004dd041
136 #define ATH8030_PHY_ID 0x004dd076
137 #define ATH8031_PHY_ID 0x004dd074
138 #define ATH8032_PHY_ID 0x004dd023
139 #define ATH8035_PHY_ID 0x004dd072
140 #define AT8030_PHY_ID_MASK			0xffffffef
141 
142 MODULE_DESCRIPTION("Qualcomm Atheros AR803x PHY driver");
143 MODULE_AUTHOR("Matus Ujhelyi");
144 MODULE_LICENSE("GPL");
145 
146 struct at803x_priv {
147 	int flags;
148 #define AT803X_KEEP_PLL_ENABLED	BIT(0)	/* don't turn off internal PLL */
149 	u16 clk_25m_reg;
150 	u16 clk_25m_mask;
151 	struct regulator_dev *vddio_rdev;
152 	struct regulator_dev *vddh_rdev;
153 	struct regulator *vddio;
154 };
155 
156 struct at803x_context {
157 	u16 bmcr;
158 	u16 advertise;
159 	u16 control1000;
160 	u16 int_enable;
161 	u16 smart_speed;
162 	u16 led_control;
163 };
164 
165 static int at803x_debug_reg_read(struct phy_device *phydev, u16 reg)
166 {
167 	int ret;
168 
169 	ret = phy_write(phydev, AT803X_DEBUG_ADDR, reg);
170 	if (ret < 0)
171 		return ret;
172 
173 	return phy_read(phydev, AT803X_DEBUG_DATA);
174 }
175 
176 static int at803x_debug_reg_mask(struct phy_device *phydev, u16 reg,
177 				 u16 clear, u16 set)
178 {
179 	u16 val;
180 	int ret;
181 
182 	ret = at803x_debug_reg_read(phydev, reg);
183 	if (ret < 0)
184 		return ret;
185 
186 	val = ret & 0xffff;
187 	val &= ~clear;
188 	val |= set;
189 
190 	return phy_write(phydev, AT803X_DEBUG_DATA, val);
191 }
192 
193 static int at803x_enable_rx_delay(struct phy_device *phydev)
194 {
195 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0, 0,
196 				     AT803X_DEBUG_RX_CLK_DLY_EN);
197 }
198 
199 static int at803x_enable_tx_delay(struct phy_device *phydev)
200 {
201 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5, 0,
202 				     AT803X_DEBUG_TX_CLK_DLY_EN);
203 }
204 
205 static int at803x_disable_rx_delay(struct phy_device *phydev)
206 {
207 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_0,
208 				     AT803X_DEBUG_RX_CLK_DLY_EN, 0);
209 }
210 
211 static int at803x_disable_tx_delay(struct phy_device *phydev)
212 {
213 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_5,
214 				     AT803X_DEBUG_TX_CLK_DLY_EN, 0);
215 }
216 
217 /* save relevant PHY registers to private copy */
218 static void at803x_context_save(struct phy_device *phydev,
219 				struct at803x_context *context)
220 {
221 	context->bmcr = phy_read(phydev, MII_BMCR);
222 	context->advertise = phy_read(phydev, MII_ADVERTISE);
223 	context->control1000 = phy_read(phydev, MII_CTRL1000);
224 	context->int_enable = phy_read(phydev, AT803X_INTR_ENABLE);
225 	context->smart_speed = phy_read(phydev, AT803X_SMART_SPEED);
226 	context->led_control = phy_read(phydev, AT803X_LED_CONTROL);
227 }
228 
229 /* restore relevant PHY registers from private copy */
230 static void at803x_context_restore(struct phy_device *phydev,
231 				   const struct at803x_context *context)
232 {
233 	phy_write(phydev, MII_BMCR, context->bmcr);
234 	phy_write(phydev, MII_ADVERTISE, context->advertise);
235 	phy_write(phydev, MII_CTRL1000, context->control1000);
236 	phy_write(phydev, AT803X_INTR_ENABLE, context->int_enable);
237 	phy_write(phydev, AT803X_SMART_SPEED, context->smart_speed);
238 	phy_write(phydev, AT803X_LED_CONTROL, context->led_control);
239 }
240 
241 static int at803x_set_wol(struct phy_device *phydev,
242 			  struct ethtool_wolinfo *wol)
243 {
244 	struct net_device *ndev = phydev->attached_dev;
245 	const u8 *mac;
246 	int ret;
247 	u32 value;
248 	unsigned int i, offsets[] = {
249 		AT803X_LOC_MAC_ADDR_32_47_OFFSET,
250 		AT803X_LOC_MAC_ADDR_16_31_OFFSET,
251 		AT803X_LOC_MAC_ADDR_0_15_OFFSET,
252 	};
253 
254 	if (!ndev)
255 		return -ENODEV;
256 
257 	if (wol->wolopts & WAKE_MAGIC) {
258 		mac = (const u8 *) ndev->dev_addr;
259 
260 		if (!is_valid_ether_addr(mac))
261 			return -EINVAL;
262 
263 		for (i = 0; i < 3; i++)
264 			phy_write_mmd(phydev, AT803X_DEVICE_ADDR, offsets[i],
265 				      mac[(i * 2) + 1] | (mac[(i * 2)] << 8));
266 
267 		value = phy_read(phydev, AT803X_INTR_ENABLE);
268 		value |= AT803X_INTR_ENABLE_WOL;
269 		ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
270 		if (ret)
271 			return ret;
272 		value = phy_read(phydev, AT803X_INTR_STATUS);
273 	} else {
274 		value = phy_read(phydev, AT803X_INTR_ENABLE);
275 		value &= (~AT803X_INTR_ENABLE_WOL);
276 		ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
277 		if (ret)
278 			return ret;
279 		value = phy_read(phydev, AT803X_INTR_STATUS);
280 	}
281 
282 	return ret;
283 }
284 
285 static void at803x_get_wol(struct phy_device *phydev,
286 			   struct ethtool_wolinfo *wol)
287 {
288 	u32 value;
289 
290 	wol->supported = WAKE_MAGIC;
291 	wol->wolopts = 0;
292 
293 	value = phy_read(phydev, AT803X_INTR_ENABLE);
294 	if (value & AT803X_INTR_ENABLE_WOL)
295 		wol->wolopts |= WAKE_MAGIC;
296 }
297 
298 static int at803x_suspend(struct phy_device *phydev)
299 {
300 	int value;
301 	int wol_enabled;
302 
303 	value = phy_read(phydev, AT803X_INTR_ENABLE);
304 	wol_enabled = value & AT803X_INTR_ENABLE_WOL;
305 
306 	if (wol_enabled)
307 		value = BMCR_ISOLATE;
308 	else
309 		value = BMCR_PDOWN;
310 
311 	phy_modify(phydev, MII_BMCR, 0, value);
312 
313 	return 0;
314 }
315 
316 static int at803x_resume(struct phy_device *phydev)
317 {
318 	return phy_modify(phydev, MII_BMCR, BMCR_PDOWN | BMCR_ISOLATE, 0);
319 }
320 
321 static int at803x_rgmii_reg_set_voltage_sel(struct regulator_dev *rdev,
322 					    unsigned int selector)
323 {
324 	struct phy_device *phydev = rdev_get_drvdata(rdev);
325 
326 	if (selector)
327 		return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_1F,
328 					     0, AT803X_DEBUG_RGMII_1V8);
329 	else
330 		return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_1F,
331 					     AT803X_DEBUG_RGMII_1V8, 0);
332 }
333 
334 static int at803x_rgmii_reg_get_voltage_sel(struct regulator_dev *rdev)
335 {
336 	struct phy_device *phydev = rdev_get_drvdata(rdev);
337 	int val;
338 
339 	val = at803x_debug_reg_read(phydev, AT803X_DEBUG_REG_1F);
340 	if (val < 0)
341 		return val;
342 
343 	return (val & AT803X_DEBUG_RGMII_1V8) ? 1 : 0;
344 }
345 
346 static struct regulator_ops vddio_regulator_ops = {
347 	.list_voltage = regulator_list_voltage_table,
348 	.set_voltage_sel = at803x_rgmii_reg_set_voltage_sel,
349 	.get_voltage_sel = at803x_rgmii_reg_get_voltage_sel,
350 };
351 
352 static const unsigned int vddio_voltage_table[] = {
353 	1500000,
354 	1800000,
355 };
356 
357 static const struct regulator_desc vddio_desc = {
358 	.name = "vddio",
359 	.of_match = of_match_ptr("vddio-regulator"),
360 	.n_voltages = ARRAY_SIZE(vddio_voltage_table),
361 	.volt_table = vddio_voltage_table,
362 	.ops = &vddio_regulator_ops,
363 	.type = REGULATOR_VOLTAGE,
364 	.owner = THIS_MODULE,
365 };
366 
367 static struct regulator_ops vddh_regulator_ops = {
368 };
369 
370 static const struct regulator_desc vddh_desc = {
371 	.name = "vddh",
372 	.of_match = of_match_ptr("vddh-regulator"),
373 	.n_voltages = 1,
374 	.fixed_uV = 2500000,
375 	.ops = &vddh_regulator_ops,
376 	.type = REGULATOR_VOLTAGE,
377 	.owner = THIS_MODULE,
378 };
379 
380 static int at8031_register_regulators(struct phy_device *phydev)
381 {
382 	struct at803x_priv *priv = phydev->priv;
383 	struct device *dev = &phydev->mdio.dev;
384 	struct regulator_config config = { };
385 
386 	config.dev = dev;
387 	config.driver_data = phydev;
388 
389 	priv->vddio_rdev = devm_regulator_register(dev, &vddio_desc, &config);
390 	if (IS_ERR(priv->vddio_rdev)) {
391 		phydev_err(phydev, "failed to register VDDIO regulator\n");
392 		return PTR_ERR(priv->vddio_rdev);
393 	}
394 
395 	priv->vddh_rdev = devm_regulator_register(dev, &vddh_desc, &config);
396 	if (IS_ERR(priv->vddh_rdev)) {
397 		phydev_err(phydev, "failed to register VDDH regulator\n");
398 		return PTR_ERR(priv->vddh_rdev);
399 	}
400 
401 	return 0;
402 }
403 
404 static bool at803x_match_phy_id(struct phy_device *phydev, u32 phy_id)
405 {
406 	return (phydev->phy_id & phydev->drv->phy_id_mask)
407 		== (phy_id & phydev->drv->phy_id_mask);
408 }
409 
410 static int at803x_parse_dt(struct phy_device *phydev)
411 {
412 	struct device_node *node = phydev->mdio.dev.of_node;
413 	struct at803x_priv *priv = phydev->priv;
414 	u32 freq, strength;
415 	unsigned int sel;
416 	int ret;
417 
418 	if (!IS_ENABLED(CONFIG_OF_MDIO))
419 		return 0;
420 
421 	ret = of_property_read_u32(node, "qca,clk-out-frequency", &freq);
422 	if (!ret) {
423 		switch (freq) {
424 		case 25000000:
425 			sel = AT803X_CLK_OUT_25MHZ_XTAL;
426 			break;
427 		case 50000000:
428 			sel = AT803X_CLK_OUT_50MHZ_PLL;
429 			break;
430 		case 62500000:
431 			sel = AT803X_CLK_OUT_62_5MHZ_PLL;
432 			break;
433 		case 125000000:
434 			sel = AT803X_CLK_OUT_125MHZ_PLL;
435 			break;
436 		default:
437 			phydev_err(phydev, "invalid qca,clk-out-frequency\n");
438 			return -EINVAL;
439 		}
440 
441 		priv->clk_25m_reg |= FIELD_PREP(AT803X_CLK_OUT_MASK, sel);
442 		priv->clk_25m_mask |= AT803X_CLK_OUT_MASK;
443 
444 		/* Fixup for the AR8030/AR8035. This chip has another mask and
445 		 * doesn't support the DSP reference. Eg. the lowest bit of the
446 		 * mask. The upper two bits select the same frequencies. Mask
447 		 * the lowest bit here.
448 		 *
449 		 * Warning:
450 		 *   There was no datasheet for the AR8030 available so this is
451 		 *   just a guess. But the AR8035 is listed as pin compatible
452 		 *   to the AR8030 so there might be a good chance it works on
453 		 *   the AR8030 too.
454 		 */
455 		if (at803x_match_phy_id(phydev, ATH8030_PHY_ID) ||
456 		    at803x_match_phy_id(phydev, ATH8035_PHY_ID)) {
457 			priv->clk_25m_reg &= AT8035_CLK_OUT_MASK;
458 			priv->clk_25m_mask &= AT8035_CLK_OUT_MASK;
459 		}
460 	}
461 
462 	ret = of_property_read_u32(node, "qca,clk-out-strength", &strength);
463 	if (!ret) {
464 		priv->clk_25m_mask |= AT803X_CLK_OUT_STRENGTH_MASK;
465 		switch (strength) {
466 		case AR803X_STRENGTH_FULL:
467 			priv->clk_25m_reg |= AT803X_CLK_OUT_STRENGTH_FULL;
468 			break;
469 		case AR803X_STRENGTH_HALF:
470 			priv->clk_25m_reg |= AT803X_CLK_OUT_STRENGTH_HALF;
471 			break;
472 		case AR803X_STRENGTH_QUARTER:
473 			priv->clk_25m_reg |= AT803X_CLK_OUT_STRENGTH_QUARTER;
474 			break;
475 		default:
476 			phydev_err(phydev, "invalid qca,clk-out-strength\n");
477 			return -EINVAL;
478 		}
479 	}
480 
481 	/* Only supported on AR8031/AR8033, the AR8030/AR8035 use strapping
482 	 * options.
483 	 */
484 	if (at803x_match_phy_id(phydev, ATH8031_PHY_ID)) {
485 		if (of_property_read_bool(node, "qca,keep-pll-enabled"))
486 			priv->flags |= AT803X_KEEP_PLL_ENABLED;
487 
488 		ret = at8031_register_regulators(phydev);
489 		if (ret < 0)
490 			return ret;
491 
492 		priv->vddio = devm_regulator_get_optional(&phydev->mdio.dev,
493 							  "vddio");
494 		if (IS_ERR(priv->vddio)) {
495 			phydev_err(phydev, "failed to get VDDIO regulator\n");
496 			return PTR_ERR(priv->vddio);
497 		}
498 
499 		ret = regulator_enable(priv->vddio);
500 		if (ret < 0)
501 			return ret;
502 	}
503 
504 	return 0;
505 }
506 
507 static int at803x_probe(struct phy_device *phydev)
508 {
509 	struct device *dev = &phydev->mdio.dev;
510 	struct at803x_priv *priv;
511 
512 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
513 	if (!priv)
514 		return -ENOMEM;
515 
516 	phydev->priv = priv;
517 
518 	return at803x_parse_dt(phydev);
519 }
520 
521 static void at803x_remove(struct phy_device *phydev)
522 {
523 	struct at803x_priv *priv = phydev->priv;
524 
525 	if (priv->vddio)
526 		regulator_disable(priv->vddio);
527 }
528 
529 static int at803x_clk_out_config(struct phy_device *phydev)
530 {
531 	struct at803x_priv *priv = phydev->priv;
532 	int val;
533 
534 	if (!priv->clk_25m_mask)
535 		return 0;
536 
537 	val = phy_read_mmd(phydev, MDIO_MMD_AN, AT803X_MMD7_CLK25M);
538 	if (val < 0)
539 		return val;
540 
541 	val &= ~priv->clk_25m_mask;
542 	val |= priv->clk_25m_reg;
543 
544 	return phy_write_mmd(phydev, MDIO_MMD_AN, AT803X_MMD7_CLK25M, val);
545 }
546 
547 static int at8031_pll_config(struct phy_device *phydev)
548 {
549 	struct at803x_priv *priv = phydev->priv;
550 
551 	/* The default after hardware reset is PLL OFF. After a soft reset, the
552 	 * values are retained.
553 	 */
554 	if (priv->flags & AT803X_KEEP_PLL_ENABLED)
555 		return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_1F,
556 					     0, AT803X_DEBUG_PLL_ON);
557 	else
558 		return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_1F,
559 					     AT803X_DEBUG_PLL_ON, 0);
560 }
561 
562 static int at803x_config_init(struct phy_device *phydev)
563 {
564 	int ret;
565 
566 	/* The RX and TX delay default is:
567 	 *   after HW reset: RX delay enabled and TX delay disabled
568 	 *   after SW reset: RX delay enabled, while TX delay retains the
569 	 *   value before reset.
570 	 */
571 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
572 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID)
573 		ret = at803x_enable_rx_delay(phydev);
574 	else
575 		ret = at803x_disable_rx_delay(phydev);
576 	if (ret < 0)
577 		return ret;
578 
579 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
580 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
581 		ret = at803x_enable_tx_delay(phydev);
582 	else
583 		ret = at803x_disable_tx_delay(phydev);
584 	if (ret < 0)
585 		return ret;
586 
587 	ret = at803x_clk_out_config(phydev);
588 	if (ret < 0)
589 		return ret;
590 
591 	if (at803x_match_phy_id(phydev, ATH8031_PHY_ID)) {
592 		ret = at8031_pll_config(phydev);
593 		if (ret < 0)
594 			return ret;
595 	}
596 
597 	return 0;
598 }
599 
600 static int at803x_ack_interrupt(struct phy_device *phydev)
601 {
602 	int err;
603 
604 	err = phy_read(phydev, AT803X_INTR_STATUS);
605 
606 	return (err < 0) ? err : 0;
607 }
608 
609 static int at803x_config_intr(struct phy_device *phydev)
610 {
611 	int err;
612 	int value;
613 
614 	value = phy_read(phydev, AT803X_INTR_ENABLE);
615 
616 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
617 		value |= AT803X_INTR_ENABLE_AUTONEG_ERR;
618 		value |= AT803X_INTR_ENABLE_SPEED_CHANGED;
619 		value |= AT803X_INTR_ENABLE_DUPLEX_CHANGED;
620 		value |= AT803X_INTR_ENABLE_LINK_FAIL;
621 		value |= AT803X_INTR_ENABLE_LINK_SUCCESS;
622 
623 		err = phy_write(phydev, AT803X_INTR_ENABLE, value);
624 	}
625 	else
626 		err = phy_write(phydev, AT803X_INTR_ENABLE, 0);
627 
628 	return err;
629 }
630 
631 static void at803x_link_change_notify(struct phy_device *phydev)
632 {
633 	/*
634 	 * Conduct a hardware reset for AT8030 every time a link loss is
635 	 * signalled. This is necessary to circumvent a hardware bug that
636 	 * occurs when the cable is unplugged while TX packets are pending
637 	 * in the FIFO. In such cases, the FIFO enters an error mode it
638 	 * cannot recover from by software.
639 	 */
640 	if (phydev->state == PHY_NOLINK && phydev->mdio.reset_gpio) {
641 		struct at803x_context context;
642 
643 		at803x_context_save(phydev, &context);
644 
645 		phy_device_reset(phydev, 1);
646 		msleep(1);
647 		phy_device_reset(phydev, 0);
648 		msleep(1);
649 
650 		at803x_context_restore(phydev, &context);
651 
652 		phydev_dbg(phydev, "%s(): phy was reset\n", __func__);
653 	}
654 }
655 
656 static int at803x_aneg_done(struct phy_device *phydev)
657 {
658 	int ccr;
659 
660 	int aneg_done = genphy_aneg_done(phydev);
661 	if (aneg_done != BMSR_ANEGCOMPLETE)
662 		return aneg_done;
663 
664 	/*
665 	 * in SGMII mode, if copper side autoneg is successful,
666 	 * also check SGMII side autoneg result
667 	 */
668 	ccr = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
669 	if ((ccr & AT803X_MODE_CFG_MASK) != AT803X_MODE_CFG_SGMII)
670 		return aneg_done;
671 
672 	/* switch to SGMII/fiber page */
673 	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr & ~AT803X_BT_BX_REG_SEL);
674 
675 	/* check if the SGMII link is OK. */
676 	if (!(phy_read(phydev, AT803X_PSSR) & AT803X_PSSR_MR_AN_COMPLETE)) {
677 		phydev_warn(phydev, "803x_aneg_done: SGMII link is not ok\n");
678 		aneg_done = 0;
679 	}
680 	/* switch back to copper page */
681 	phy_write(phydev, AT803X_REG_CHIP_CONFIG, ccr | AT803X_BT_BX_REG_SEL);
682 
683 	return aneg_done;
684 }
685 
686 static int at803x_read_status(struct phy_device *phydev)
687 {
688 	int ss, err, old_link = phydev->link;
689 
690 	/* Update the link, but return if there was an error */
691 	err = genphy_update_link(phydev);
692 	if (err)
693 		return err;
694 
695 	/* why bother the PHY if nothing can have changed */
696 	if (phydev->autoneg == AUTONEG_ENABLE && old_link && phydev->link)
697 		return 0;
698 
699 	phydev->speed = SPEED_UNKNOWN;
700 	phydev->duplex = DUPLEX_UNKNOWN;
701 	phydev->pause = 0;
702 	phydev->asym_pause = 0;
703 
704 	err = genphy_read_lpa(phydev);
705 	if (err < 0)
706 		return err;
707 
708 	/* Read the AT8035 PHY-Specific Status register, which indicates the
709 	 * speed and duplex that the PHY is actually using, irrespective of
710 	 * whether we are in autoneg mode or not.
711 	 */
712 	ss = phy_read(phydev, AT803X_SPECIFIC_STATUS);
713 	if (ss < 0)
714 		return ss;
715 
716 	if (ss & AT803X_SS_SPEED_DUPLEX_RESOLVED) {
717 		int sfc;
718 
719 		sfc = phy_read(phydev, AT803X_SPECIFIC_FUNCTION_CONTROL);
720 		if (sfc < 0)
721 			return sfc;
722 
723 		switch (ss & AT803X_SS_SPEED_MASK) {
724 		case AT803X_SS_SPEED_10:
725 			phydev->speed = SPEED_10;
726 			break;
727 		case AT803X_SS_SPEED_100:
728 			phydev->speed = SPEED_100;
729 			break;
730 		case AT803X_SS_SPEED_1000:
731 			phydev->speed = SPEED_1000;
732 			break;
733 		}
734 		if (ss & AT803X_SS_DUPLEX)
735 			phydev->duplex = DUPLEX_FULL;
736 		else
737 			phydev->duplex = DUPLEX_HALF;
738 
739 		if (ss & AT803X_SS_MDIX)
740 			phydev->mdix = ETH_TP_MDI_X;
741 		else
742 			phydev->mdix = ETH_TP_MDI;
743 
744 		switch (FIELD_GET(AT803X_SFC_MDI_CROSSOVER_MODE_M, sfc)) {
745 		case AT803X_SFC_MANUAL_MDI:
746 			phydev->mdix_ctrl = ETH_TP_MDI;
747 			break;
748 		case AT803X_SFC_MANUAL_MDIX:
749 			phydev->mdix_ctrl = ETH_TP_MDI_X;
750 			break;
751 		case AT803X_SFC_AUTOMATIC_CROSSOVER:
752 			phydev->mdix_ctrl = ETH_TP_MDI_AUTO;
753 			break;
754 		}
755 	}
756 
757 	if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete)
758 		phy_resolve_aneg_pause(phydev);
759 
760 	return 0;
761 }
762 
763 static int at803x_config_mdix(struct phy_device *phydev, u8 ctrl)
764 {
765 	u16 val;
766 
767 	switch (ctrl) {
768 	case ETH_TP_MDI:
769 		val = AT803X_SFC_MANUAL_MDI;
770 		break;
771 	case ETH_TP_MDI_X:
772 		val = AT803X_SFC_MANUAL_MDIX;
773 		break;
774 	case ETH_TP_MDI_AUTO:
775 		val = AT803X_SFC_AUTOMATIC_CROSSOVER;
776 		break;
777 	default:
778 		return 0;
779 	}
780 
781 	return phy_modify_changed(phydev, AT803X_SPECIFIC_FUNCTION_CONTROL,
782 			  AT803X_SFC_MDI_CROSSOVER_MODE_M,
783 			  FIELD_PREP(AT803X_SFC_MDI_CROSSOVER_MODE_M, val));
784 }
785 
786 static int at803x_config_aneg(struct phy_device *phydev)
787 {
788 	int ret;
789 
790 	ret = at803x_config_mdix(phydev, phydev->mdix_ctrl);
791 	if (ret < 0)
792 		return ret;
793 
794 	/* Changes of the midx bits are disruptive to the normal operation;
795 	 * therefore any changes to these registers must be followed by a
796 	 * software reset to take effect.
797 	 */
798 	if (ret == 1) {
799 		ret = genphy_soft_reset(phydev);
800 		if (ret < 0)
801 			return ret;
802 	}
803 
804 	return genphy_config_aneg(phydev);
805 }
806 
807 static int at803x_get_downshift(struct phy_device *phydev, u8 *d)
808 {
809 	int val;
810 
811 	val = phy_read(phydev, AT803X_SMART_SPEED);
812 	if (val < 0)
813 		return val;
814 
815 	if (val & AT803X_SMART_SPEED_ENABLE)
816 		*d = FIELD_GET(AT803X_SMART_SPEED_RETRY_LIMIT_MASK, val) + 2;
817 	else
818 		*d = DOWNSHIFT_DEV_DISABLE;
819 
820 	return 0;
821 }
822 
823 static int at803x_set_downshift(struct phy_device *phydev, u8 cnt)
824 {
825 	u16 mask, set;
826 	int ret;
827 
828 	switch (cnt) {
829 	case DOWNSHIFT_DEV_DEFAULT_COUNT:
830 		cnt = AT803X_DEFAULT_DOWNSHIFT;
831 		fallthrough;
832 	case AT803X_MIN_DOWNSHIFT ... AT803X_MAX_DOWNSHIFT:
833 		set = AT803X_SMART_SPEED_ENABLE |
834 		      AT803X_SMART_SPEED_BYPASS_TIMER |
835 		      FIELD_PREP(AT803X_SMART_SPEED_RETRY_LIMIT_MASK, cnt - 2);
836 		mask = AT803X_SMART_SPEED_RETRY_LIMIT_MASK;
837 		break;
838 	case DOWNSHIFT_DEV_DISABLE:
839 		set = 0;
840 		mask = AT803X_SMART_SPEED_ENABLE |
841 		       AT803X_SMART_SPEED_BYPASS_TIMER;
842 		break;
843 	default:
844 		return -EINVAL;
845 	}
846 
847 	ret = phy_modify_changed(phydev, AT803X_SMART_SPEED, mask, set);
848 
849 	/* After changing the smart speed settings, we need to perform a
850 	 * software reset, use phy_init_hw() to make sure we set the
851 	 * reapply any values which might got lost during software reset.
852 	 */
853 	if (ret == 1)
854 		ret = phy_init_hw(phydev);
855 
856 	return ret;
857 }
858 
859 static int at803x_get_tunable(struct phy_device *phydev,
860 			      struct ethtool_tunable *tuna, void *data)
861 {
862 	switch (tuna->id) {
863 	case ETHTOOL_PHY_DOWNSHIFT:
864 		return at803x_get_downshift(phydev, data);
865 	default:
866 		return -EOPNOTSUPP;
867 	}
868 }
869 
870 static int at803x_set_tunable(struct phy_device *phydev,
871 			      struct ethtool_tunable *tuna, const void *data)
872 {
873 	switch (tuna->id) {
874 	case ETHTOOL_PHY_DOWNSHIFT:
875 		return at803x_set_downshift(phydev, *(const u8 *)data);
876 	default:
877 		return -EOPNOTSUPP;
878 	}
879 }
880 
881 static int at803x_cable_test_result_trans(u16 status)
882 {
883 	switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) {
884 	case AT803X_CDT_STATUS_STAT_NORMAL:
885 		return ETHTOOL_A_CABLE_RESULT_CODE_OK;
886 	case AT803X_CDT_STATUS_STAT_SHORT:
887 		return ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT;
888 	case AT803X_CDT_STATUS_STAT_OPEN:
889 		return ETHTOOL_A_CABLE_RESULT_CODE_OPEN;
890 	case AT803X_CDT_STATUS_STAT_FAIL:
891 	default:
892 		return ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC;
893 	}
894 }
895 
896 static bool at803x_cdt_test_failed(u16 status)
897 {
898 	return FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status) ==
899 		AT803X_CDT_STATUS_STAT_FAIL;
900 }
901 
902 static bool at803x_cdt_fault_length_valid(u16 status)
903 {
904 	switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) {
905 	case AT803X_CDT_STATUS_STAT_OPEN:
906 	case AT803X_CDT_STATUS_STAT_SHORT:
907 		return true;
908 	}
909 	return false;
910 }
911 
912 static int at803x_cdt_fault_length(u16 status)
913 {
914 	int dt;
915 
916 	/* According to the datasheet the distance to the fault is
917 	 * DELTA_TIME * 0.824 meters.
918 	 *
919 	 * The author suspect the correct formula is:
920 	 *
921 	 *   fault_distance = DELTA_TIME * (c * VF) / 125MHz / 2
922 	 *
923 	 * where c is the speed of light, VF is the velocity factor of
924 	 * the twisted pair cable, 125MHz the counter frequency and
925 	 * we need to divide by 2 because the hardware will measure the
926 	 * round trip time to the fault and back to the PHY.
927 	 *
928 	 * With a VF of 0.69 we get the factor 0.824 mentioned in the
929 	 * datasheet.
930 	 */
931 	dt = FIELD_GET(AT803X_CDT_STATUS_DELTA_TIME_MASK, status);
932 
933 	return (dt * 824) / 10;
934 }
935 
936 static int at803x_cdt_start(struct phy_device *phydev, int pair)
937 {
938 	u16 cdt;
939 
940 	cdt = FIELD_PREP(AT803X_CDT_MDI_PAIR_MASK, pair) |
941 	      AT803X_CDT_ENABLE_TEST;
942 
943 	return phy_write(phydev, AT803X_CDT, cdt);
944 }
945 
946 static int at803x_cdt_wait_for_completion(struct phy_device *phydev)
947 {
948 	int val, ret;
949 
950 	/* One test run takes about 25ms */
951 	ret = phy_read_poll_timeout(phydev, AT803X_CDT, val,
952 				    !(val & AT803X_CDT_ENABLE_TEST),
953 				    30000, 100000, true);
954 
955 	return ret < 0 ? ret : 0;
956 }
957 
958 static int at803x_cable_test_one_pair(struct phy_device *phydev, int pair)
959 {
960 	static const int ethtool_pair[] = {
961 		ETHTOOL_A_CABLE_PAIR_A,
962 		ETHTOOL_A_CABLE_PAIR_B,
963 		ETHTOOL_A_CABLE_PAIR_C,
964 		ETHTOOL_A_CABLE_PAIR_D,
965 	};
966 	int ret, val;
967 
968 	ret = at803x_cdt_start(phydev, pair);
969 	if (ret)
970 		return ret;
971 
972 	ret = at803x_cdt_wait_for_completion(phydev);
973 	if (ret)
974 		return ret;
975 
976 	val = phy_read(phydev, AT803X_CDT_STATUS);
977 	if (val < 0)
978 		return val;
979 
980 	if (at803x_cdt_test_failed(val))
981 		return 0;
982 
983 	ethnl_cable_test_result(phydev, ethtool_pair[pair],
984 				at803x_cable_test_result_trans(val));
985 
986 	if (at803x_cdt_fault_length_valid(val))
987 		ethnl_cable_test_fault_length(phydev, ethtool_pair[pair],
988 					      at803x_cdt_fault_length(val));
989 
990 	return 1;
991 }
992 
993 static int at803x_cable_test_get_status(struct phy_device *phydev,
994 					bool *finished)
995 {
996 	unsigned long pair_mask;
997 	int retries = 20;
998 	int pair, ret;
999 
1000 	if (phydev->phy_id == ATH9331_PHY_ID ||
1001 	    phydev->phy_id == ATH8032_PHY_ID)
1002 		pair_mask = 0x3;
1003 	else
1004 		pair_mask = 0xf;
1005 
1006 	*finished = false;
1007 
1008 	/* According to the datasheet the CDT can be performed when
1009 	 * there is no link partner or when the link partner is
1010 	 * auto-negotiating. Starting the test will restart the AN
1011 	 * automatically. It seems that doing this repeatedly we will
1012 	 * get a slot where our link partner won't disturb our
1013 	 * measurement.
1014 	 */
1015 	while (pair_mask && retries--) {
1016 		for_each_set_bit(pair, &pair_mask, 4) {
1017 			ret = at803x_cable_test_one_pair(phydev, pair);
1018 			if (ret < 0)
1019 				return ret;
1020 			if (ret)
1021 				clear_bit(pair, &pair_mask);
1022 		}
1023 		if (pair_mask)
1024 			msleep(250);
1025 	}
1026 
1027 	*finished = true;
1028 
1029 	return 0;
1030 }
1031 
1032 static int at803x_cable_test_start(struct phy_device *phydev)
1033 {
1034 	/* Enable auto-negotiation, but advertise no capabilities, no link
1035 	 * will be established. A restart of the auto-negotiation is not
1036 	 * required, because the cable test will automatically break the link.
1037 	 */
1038 	phy_write(phydev, MII_BMCR, BMCR_ANENABLE);
1039 	phy_write(phydev, MII_ADVERTISE, ADVERTISE_CSMA);
1040 	if (phydev->phy_id != ATH9331_PHY_ID &&
1041 	    phydev->phy_id != ATH8032_PHY_ID)
1042 		phy_write(phydev, MII_CTRL1000, 0);
1043 
1044 	/* we do all the (time consuming) work later */
1045 	return 0;
1046 }
1047 
1048 static struct phy_driver at803x_driver[] = {
1049 {
1050 	/* Qualcomm Atheros AR8035 */
1051 	PHY_ID_MATCH_EXACT(ATH8035_PHY_ID),
1052 	.name			= "Qualcomm Atheros AR8035",
1053 	.flags			= PHY_POLL_CABLE_TEST,
1054 	.probe			= at803x_probe,
1055 	.remove			= at803x_remove,
1056 	.config_aneg		= at803x_config_aneg,
1057 	.config_init		= at803x_config_init,
1058 	.soft_reset		= genphy_soft_reset,
1059 	.set_wol		= at803x_set_wol,
1060 	.get_wol		= at803x_get_wol,
1061 	.suspend		= at803x_suspend,
1062 	.resume			= at803x_resume,
1063 	/* PHY_GBIT_FEATURES */
1064 	.read_status		= at803x_read_status,
1065 	.ack_interrupt		= at803x_ack_interrupt,
1066 	.config_intr		= at803x_config_intr,
1067 	.get_tunable		= at803x_get_tunable,
1068 	.set_tunable		= at803x_set_tunable,
1069 	.cable_test_start	= at803x_cable_test_start,
1070 	.cable_test_get_status	= at803x_cable_test_get_status,
1071 }, {
1072 	/* Qualcomm Atheros AR8030 */
1073 	.phy_id			= ATH8030_PHY_ID,
1074 	.name			= "Qualcomm Atheros AR8030",
1075 	.phy_id_mask		= AT8030_PHY_ID_MASK,
1076 	.probe			= at803x_probe,
1077 	.remove			= at803x_remove,
1078 	.config_init		= at803x_config_init,
1079 	.link_change_notify	= at803x_link_change_notify,
1080 	.set_wol		= at803x_set_wol,
1081 	.get_wol		= at803x_get_wol,
1082 	.suspend		= at803x_suspend,
1083 	.resume			= at803x_resume,
1084 	/* PHY_BASIC_FEATURES */
1085 	.ack_interrupt		= at803x_ack_interrupt,
1086 	.config_intr		= at803x_config_intr,
1087 }, {
1088 	/* Qualcomm Atheros AR8031/AR8033 */
1089 	PHY_ID_MATCH_EXACT(ATH8031_PHY_ID),
1090 	.name			= "Qualcomm Atheros AR8031/AR8033",
1091 	.flags			= PHY_POLL_CABLE_TEST,
1092 	.probe			= at803x_probe,
1093 	.remove			= at803x_remove,
1094 	.config_init		= at803x_config_init,
1095 	.soft_reset		= genphy_soft_reset,
1096 	.set_wol		= at803x_set_wol,
1097 	.get_wol		= at803x_get_wol,
1098 	.suspend		= at803x_suspend,
1099 	.resume			= at803x_resume,
1100 	/* PHY_GBIT_FEATURES */
1101 	.read_status		= at803x_read_status,
1102 	.aneg_done		= at803x_aneg_done,
1103 	.ack_interrupt		= &at803x_ack_interrupt,
1104 	.config_intr		= &at803x_config_intr,
1105 	.get_tunable		= at803x_get_tunable,
1106 	.set_tunable		= at803x_set_tunable,
1107 	.cable_test_start	= at803x_cable_test_start,
1108 	.cable_test_get_status	= at803x_cable_test_get_status,
1109 }, {
1110 	/* Qualcomm Atheros AR8032 */
1111 	PHY_ID_MATCH_EXACT(ATH8032_PHY_ID),
1112 	.name			= "Qualcomm Atheros AR8032",
1113 	.probe			= at803x_probe,
1114 	.remove			= at803x_remove,
1115 	.flags			= PHY_POLL_CABLE_TEST,
1116 	.config_init		= at803x_config_init,
1117 	.link_change_notify	= at803x_link_change_notify,
1118 	.set_wol		= at803x_set_wol,
1119 	.get_wol		= at803x_get_wol,
1120 	.suspend		= at803x_suspend,
1121 	.resume			= at803x_resume,
1122 	/* PHY_BASIC_FEATURES */
1123 	.ack_interrupt		= at803x_ack_interrupt,
1124 	.config_intr		= at803x_config_intr,
1125 	.cable_test_start	= at803x_cable_test_start,
1126 	.cable_test_get_status	= at803x_cable_test_get_status,
1127 }, {
1128 	/* ATHEROS AR9331 */
1129 	PHY_ID_MATCH_EXACT(ATH9331_PHY_ID),
1130 	.name			= "Qualcomm Atheros AR9331 built-in PHY",
1131 	.suspend		= at803x_suspend,
1132 	.resume			= at803x_resume,
1133 	.flags			= PHY_POLL_CABLE_TEST,
1134 	/* PHY_BASIC_FEATURES */
1135 	.ack_interrupt		= &at803x_ack_interrupt,
1136 	.config_intr		= &at803x_config_intr,
1137 	.cable_test_start	= at803x_cable_test_start,
1138 	.cable_test_get_status	= at803x_cable_test_get_status,
1139 	.read_status		= at803x_read_status,
1140 	.soft_reset		= genphy_soft_reset,
1141 	.config_aneg		= at803x_config_aneg,
1142 } };
1143 
1144 module_phy_driver(at803x_driver);
1145 
1146 static struct mdio_device_id __maybe_unused atheros_tbl[] = {
1147 	{ ATH8030_PHY_ID, AT8030_PHY_ID_MASK },
1148 	{ PHY_ID_MATCH_EXACT(ATH8031_PHY_ID) },
1149 	{ PHY_ID_MATCH_EXACT(ATH8032_PHY_ID) },
1150 	{ PHY_ID_MATCH_EXACT(ATH8035_PHY_ID) },
1151 	{ PHY_ID_MATCH_EXACT(ATH9331_PHY_ID) },
1152 	{ }
1153 };
1154 
1155 MODULE_DEVICE_TABLE(mdio, atheros_tbl);
1156