xref: /linux/drivers/net/pcs/pcs-rzn1-miic.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2022 Schneider Electric
4  *
5  * Clément Léger <clement.leger@bootlin.com>
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/device.h>
10 #include <linux/mdio.h>
11 #include <linux/of.h>
12 #include <linux/of_platform.h>
13 #include <linux/pcs-rzn1-miic.h>
14 #include <linux/phylink.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <dt-bindings/net/pcs-rzn1-miic.h>
18 
19 #define MIIC_PRCMD			0x0
20 #define MIIC_ESID_CODE			0x4
21 
22 #define MIIC_MODCTRL			0x20
23 #define MIIC_MODCTRL_SW_MODE		GENMASK(4, 0)
24 
25 #define MIIC_CONVCTRL(port)		(0x100 + (port) * 4)
26 
27 #define MIIC_CONVCTRL_CONV_SPEED	GENMASK(1, 0)
28 #define CONV_MODE_10MBPS		0
29 #define CONV_MODE_100MBPS		1
30 #define CONV_MODE_1000MBPS		2
31 
32 #define MIIC_CONVCTRL_CONV_MODE		GENMASK(3, 2)
33 #define CONV_MODE_MII			0
34 #define CONV_MODE_RMII			1
35 #define CONV_MODE_RGMII			2
36 
37 #define MIIC_CONVCTRL_FULLD		BIT(8)
38 #define MIIC_CONVCTRL_RGMII_LINK	BIT(12)
39 #define MIIC_CONVCTRL_RGMII_DUPLEX	BIT(13)
40 #define MIIC_CONVCTRL_RGMII_SPEED	GENMASK(15, 14)
41 
42 #define MIIC_CONVRST			0x114
43 #define MIIC_CONVRST_PHYIF_RST(port)	BIT(port)
44 #define MIIC_CONVRST_PHYIF_RST_MASK	GENMASK(4, 0)
45 
46 #define MIIC_SWCTRL			0x304
47 #define MIIC_SWDUPC			0x308
48 
49 #define MIIC_MAX_NR_PORTS		5
50 
51 #define MIIC_MODCTRL_CONF_CONV_NUM	6
52 #define MIIC_MODCTRL_CONF_NONE		-1
53 
54 /**
55  * struct modctrl_match - Matching table entry for  convctrl configuration
56  *			  See section 8.2.1 of manual.
57  * @mode_cfg: Configuration value for convctrl
58  * @conv: Configuration of ethernet port muxes. First index is SWITCH_PORTIN,
59  *	  then index 1 - 5 are CONV1 - CONV5.
60  */
61 struct modctrl_match {
62 	u32 mode_cfg;
63 	u8 conv[MIIC_MODCTRL_CONF_CONV_NUM];
64 };
65 
66 static struct modctrl_match modctrl_match_table[] = {
67 	{0x0, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
68 	       MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
69 	{0x1, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
70 	       MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
71 	{0x2, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
72 	       MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
73 	{0x3, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
74 	       MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}},
75 
76 	{0x8, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
77 	       MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
78 	{0x9, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
79 	       MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
80 	{0xA, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
81 	       MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
82 	{0xB, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
83 	       MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}},
84 
85 	{0x10, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
86 		MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
87 	{0x11, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
88 		MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
89 	{0x12, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
90 		MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
91 	{0x13, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
92 		MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}}
93 };
94 
95 static const char * const conf_to_string[] = {
96 	[MIIC_GMAC1_PORT]	= "GMAC1_PORT",
97 	[MIIC_GMAC2_PORT]	= "GMAC2_PORT",
98 	[MIIC_RTOS_PORT]	= "RTOS_PORT",
99 	[MIIC_SERCOS_PORTA]	= "SERCOS_PORTA",
100 	[MIIC_SERCOS_PORTB]	= "SERCOS_PORTB",
101 	[MIIC_ETHERCAT_PORTA]	= "ETHERCAT_PORTA",
102 	[MIIC_ETHERCAT_PORTB]	= "ETHERCAT_PORTB",
103 	[MIIC_ETHERCAT_PORTC]	= "ETHERCAT_PORTC",
104 	[MIIC_SWITCH_PORTA]	= "SWITCH_PORTA",
105 	[MIIC_SWITCH_PORTB]	= "SWITCH_PORTB",
106 	[MIIC_SWITCH_PORTC]	= "SWITCH_PORTC",
107 	[MIIC_SWITCH_PORTD]	= "SWITCH_PORTD",
108 	[MIIC_HSR_PORTA]	= "HSR_PORTA",
109 	[MIIC_HSR_PORTB]	= "HSR_PORTB",
110 };
111 
112 static const char *index_to_string[MIIC_MODCTRL_CONF_CONV_NUM] = {
113 	"SWITCH_PORTIN",
114 	"CONV1",
115 	"CONV2",
116 	"CONV3",
117 	"CONV4",
118 	"CONV5",
119 };
120 
121 /**
122  * struct miic - MII converter structure
123  * @base: base address of the MII converter
124  * @dev: Device associated to the MII converter
125  * @lock: Lock used for read-modify-write access
126  */
127 struct miic {
128 	void __iomem *base;
129 	struct device *dev;
130 	spinlock_t lock;
131 };
132 
133 /**
134  * struct miic_port - Per port MII converter struct
135  * @miic: backiling to MII converter structure
136  * @pcs: PCS structure associated to the port
137  * @port: port number
138  * @interface: interface mode of the port
139  */
140 struct miic_port {
141 	struct miic *miic;
142 	struct phylink_pcs pcs;
143 	int port;
144 	phy_interface_t interface;
145 };
146 
147 static struct miic_port *phylink_pcs_to_miic_port(struct phylink_pcs *pcs)
148 {
149 	return container_of(pcs, struct miic_port, pcs);
150 }
151 
152 static void miic_reg_writel(struct miic *miic, int offset, u32 value)
153 {
154 	writel(value, miic->base + offset);
155 }
156 
157 static u32 miic_reg_readl(struct miic *miic, int offset)
158 {
159 	return readl(miic->base + offset);
160 }
161 
162 static void miic_reg_rmw(struct miic *miic, int offset, u32 mask, u32 val)
163 {
164 	u32 reg;
165 
166 	spin_lock(&miic->lock);
167 
168 	reg = miic_reg_readl(miic, offset);
169 	reg &= ~mask;
170 	reg |= val;
171 	miic_reg_writel(miic, offset, reg);
172 
173 	spin_unlock(&miic->lock);
174 }
175 
176 static void miic_converter_enable(struct miic *miic, int port, int enable)
177 {
178 	u32 val = 0;
179 
180 	if (enable)
181 		val = MIIC_CONVRST_PHYIF_RST(port);
182 
183 	miic_reg_rmw(miic, MIIC_CONVRST, MIIC_CONVRST_PHYIF_RST(port), val);
184 }
185 
186 static int miic_config(struct phylink_pcs *pcs, unsigned int neg_mode,
187 		       phy_interface_t interface,
188 		       const unsigned long *advertising, bool permit)
189 {
190 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
191 	struct miic *miic = miic_port->miic;
192 	u32 speed, conv_mode, val, mask;
193 	int port = miic_port->port;
194 
195 	switch (interface) {
196 	case PHY_INTERFACE_MODE_RMII:
197 		conv_mode = CONV_MODE_RMII;
198 		speed = CONV_MODE_100MBPS;
199 		break;
200 	case PHY_INTERFACE_MODE_RGMII:
201 	case PHY_INTERFACE_MODE_RGMII_ID:
202 	case PHY_INTERFACE_MODE_RGMII_TXID:
203 	case PHY_INTERFACE_MODE_RGMII_RXID:
204 		conv_mode = CONV_MODE_RGMII;
205 		speed = CONV_MODE_1000MBPS;
206 		break;
207 	case PHY_INTERFACE_MODE_MII:
208 		conv_mode = CONV_MODE_MII;
209 		/* When in MII mode, speed should be set to 0 (which is actually
210 		 * CONV_MODE_10MBPS)
211 		 */
212 		speed = CONV_MODE_10MBPS;
213 		break;
214 	default:
215 		return -EOPNOTSUPP;
216 	}
217 
218 	val = FIELD_PREP(MIIC_CONVCTRL_CONV_MODE, conv_mode);
219 	mask = MIIC_CONVCTRL_CONV_MODE;
220 
221 	/* Update speed only if we are going to change the interface because
222 	 * the link might already be up and it would break it if the speed is
223 	 * changed.
224 	 */
225 	if (interface != miic_port->interface) {
226 		val |= FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, speed);
227 		mask |= MIIC_CONVCTRL_CONV_SPEED;
228 		miic_port->interface = interface;
229 	}
230 
231 	miic_reg_rmw(miic, MIIC_CONVCTRL(port), mask, val);
232 	miic_converter_enable(miic, miic_port->port, 1);
233 
234 	return 0;
235 }
236 
237 static void miic_link_up(struct phylink_pcs *pcs, unsigned int neg_mode,
238 			 phy_interface_t interface, int speed, int duplex)
239 {
240 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
241 	struct miic *miic = miic_port->miic;
242 	u32 conv_speed = 0, val = 0;
243 	int port = miic_port->port;
244 
245 	if (duplex == DUPLEX_FULL)
246 		val |= MIIC_CONVCTRL_FULLD;
247 
248 	/* No speed in MII through-mode */
249 	if (interface != PHY_INTERFACE_MODE_MII) {
250 		switch (speed) {
251 		case SPEED_1000:
252 			conv_speed = CONV_MODE_1000MBPS;
253 			break;
254 		case SPEED_100:
255 			conv_speed = CONV_MODE_100MBPS;
256 			break;
257 		case SPEED_10:
258 			conv_speed = CONV_MODE_10MBPS;
259 			break;
260 		default:
261 			return;
262 		}
263 	}
264 
265 	val |= FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, conv_speed);
266 
267 	miic_reg_rmw(miic, MIIC_CONVCTRL(port),
268 		     (MIIC_CONVCTRL_CONV_SPEED | MIIC_CONVCTRL_FULLD), val);
269 }
270 
271 static int miic_validate(struct phylink_pcs *pcs, unsigned long *supported,
272 			 const struct phylink_link_state *state)
273 {
274 	if (phy_interface_mode_is_rgmii(state->interface) ||
275 	    state->interface == PHY_INTERFACE_MODE_RMII ||
276 	    state->interface == PHY_INTERFACE_MODE_MII)
277 		return 1;
278 
279 	return -EINVAL;
280 }
281 
282 static int miic_pre_init(struct phylink_pcs *pcs)
283 {
284 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
285 	struct miic *miic = miic_port->miic;
286 	u32 val, mask;
287 
288 	/* Start RX clock if required */
289 	if (pcs->rxc_always_on) {
290 		/* In MII through mode, the clock signals will be driven by the
291 		 * external PHY, which might not be initialized yet. Set RMII
292 		 * as default mode to ensure that a reference clock signal is
293 		 * generated.
294 		 */
295 		miic_port->interface = PHY_INTERFACE_MODE_RMII;
296 
297 		val = FIELD_PREP(MIIC_CONVCTRL_CONV_MODE, CONV_MODE_RMII) |
298 		      FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, CONV_MODE_100MBPS);
299 		mask = MIIC_CONVCTRL_CONV_MODE | MIIC_CONVCTRL_CONV_SPEED;
300 
301 		miic_reg_rmw(miic, MIIC_CONVCTRL(miic_port->port), mask, val);
302 
303 		miic_converter_enable(miic, miic_port->port, 1);
304 	}
305 
306 	return 0;
307 }
308 
309 static const struct phylink_pcs_ops miic_phylink_ops = {
310 	.pcs_validate = miic_validate,
311 	.pcs_config = miic_config,
312 	.pcs_link_up = miic_link_up,
313 	.pcs_pre_init = miic_pre_init,
314 };
315 
316 struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
317 {
318 	struct platform_device *pdev;
319 	struct miic_port *miic_port;
320 	struct device_node *pcs_np;
321 	struct miic *miic;
322 	u32 port;
323 
324 	if (!of_device_is_available(np))
325 		return ERR_PTR(-ENODEV);
326 
327 	if (of_property_read_u32(np, "reg", &port))
328 		return ERR_PTR(-EINVAL);
329 
330 	if (port > MIIC_MAX_NR_PORTS || port < 1)
331 		return ERR_PTR(-EINVAL);
332 
333 	/* The PCS pdev is attached to the parent node */
334 	pcs_np = of_get_parent(np);
335 	if (!pcs_np)
336 		return ERR_PTR(-ENODEV);
337 
338 	if (!of_device_is_available(pcs_np)) {
339 		of_node_put(pcs_np);
340 		return ERR_PTR(-ENODEV);
341 	}
342 
343 	pdev = of_find_device_by_node(pcs_np);
344 	of_node_put(pcs_np);
345 	if (!pdev || !platform_get_drvdata(pdev)) {
346 		if (pdev)
347 			put_device(&pdev->dev);
348 		return ERR_PTR(-EPROBE_DEFER);
349 	}
350 
351 	miic_port = kzalloc(sizeof(*miic_port), GFP_KERNEL);
352 	if (!miic_port) {
353 		put_device(&pdev->dev);
354 		return ERR_PTR(-ENOMEM);
355 	}
356 
357 	miic = platform_get_drvdata(pdev);
358 	device_link_add(dev, miic->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
359 	put_device(&pdev->dev);
360 
361 	miic_port->miic = miic;
362 	miic_port->port = port - 1;
363 	miic_port->pcs.ops = &miic_phylink_ops;
364 	miic_port->pcs.neg_mode = true;
365 
366 	return &miic_port->pcs;
367 }
368 EXPORT_SYMBOL(miic_create);
369 
370 void miic_destroy(struct phylink_pcs *pcs)
371 {
372 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
373 
374 	miic_converter_enable(miic_port->miic, miic_port->port, 0);
375 	kfree(miic_port);
376 }
377 EXPORT_SYMBOL(miic_destroy);
378 
379 static int miic_init_hw(struct miic *miic, u32 cfg_mode)
380 {
381 	int port;
382 
383 	/* Unlock write access to accessory registers (cf datasheet). If this
384 	 * is going to be used in conjunction with the Cortex-M3, this sequence
385 	 * will have to be moved in register write
386 	 */
387 	miic_reg_writel(miic, MIIC_PRCMD, 0x00A5);
388 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
389 	miic_reg_writel(miic, MIIC_PRCMD, 0xFFFE);
390 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
391 
392 	miic_reg_writel(miic, MIIC_MODCTRL,
393 			FIELD_PREP(MIIC_MODCTRL_SW_MODE, cfg_mode));
394 
395 	for (port = 0; port < MIIC_MAX_NR_PORTS; port++) {
396 		miic_converter_enable(miic, port, 0);
397 		/* Disable speed/duplex control from these registers, datasheet
398 		 * says switch registers should be used to setup switch port
399 		 * speed and duplex.
400 		 */
401 		miic_reg_writel(miic, MIIC_SWCTRL, 0x0);
402 		miic_reg_writel(miic, MIIC_SWDUPC, 0x0);
403 	}
404 
405 	return 0;
406 }
407 
408 static bool miic_modctrl_match(s8 table_val[MIIC_MODCTRL_CONF_CONV_NUM],
409 			       s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM])
410 {
411 	int i;
412 
413 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
414 		if (dt_val[i] == MIIC_MODCTRL_CONF_NONE)
415 			continue;
416 
417 		if (dt_val[i] != table_val[i])
418 			return false;
419 	}
420 
421 	return true;
422 }
423 
424 static void miic_dump_conf(struct device *dev,
425 			   s8 conf[MIIC_MODCTRL_CONF_CONV_NUM])
426 {
427 	const char *conf_name;
428 	int i;
429 
430 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
431 		if (conf[i] != MIIC_MODCTRL_CONF_NONE)
432 			conf_name = conf_to_string[conf[i]];
433 		else
434 			conf_name = "NONE";
435 
436 		dev_err(dev, "%s: %s\n", index_to_string[i], conf_name);
437 	}
438 }
439 
440 static int miic_match_dt_conf(struct device *dev,
441 			      s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM],
442 			      u32 *mode_cfg)
443 {
444 	struct modctrl_match *table_entry;
445 	int i;
446 
447 	for (i = 0; i < ARRAY_SIZE(modctrl_match_table); i++) {
448 		table_entry = &modctrl_match_table[i];
449 
450 		if (miic_modctrl_match(table_entry->conv, dt_val)) {
451 			*mode_cfg = table_entry->mode_cfg;
452 			return 0;
453 		}
454 	}
455 
456 	dev_err(dev, "Failed to apply requested configuration\n");
457 	miic_dump_conf(dev, dt_val);
458 
459 	return -EINVAL;
460 }
461 
462 static int miic_parse_dt(struct device *dev, u32 *mode_cfg)
463 {
464 	s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM];
465 	struct device_node *np = dev->of_node;
466 	struct device_node *conv;
467 	u32 conf;
468 	int port;
469 
470 	memset(dt_val, MIIC_MODCTRL_CONF_NONE, sizeof(dt_val));
471 
472 	if (of_property_read_u32(np, "renesas,miic-switch-portin", &conf) == 0)
473 		dt_val[0] = conf;
474 
475 	for_each_child_of_node(np, conv) {
476 		if (of_property_read_u32(conv, "reg", &port))
477 			continue;
478 
479 		if (!of_device_is_available(conv))
480 			continue;
481 
482 		if (of_property_read_u32(conv, "renesas,miic-input", &conf) == 0)
483 			dt_val[port] = conf;
484 	}
485 
486 	return miic_match_dt_conf(dev, dt_val, mode_cfg);
487 }
488 
489 static int miic_probe(struct platform_device *pdev)
490 {
491 	struct device *dev = &pdev->dev;
492 	struct miic *miic;
493 	u32 mode_cfg;
494 	int ret;
495 
496 	ret = miic_parse_dt(dev, &mode_cfg);
497 	if (ret < 0)
498 		return ret;
499 
500 	miic = devm_kzalloc(dev, sizeof(*miic), GFP_KERNEL);
501 	if (!miic)
502 		return -ENOMEM;
503 
504 	spin_lock_init(&miic->lock);
505 	miic->dev = dev;
506 	miic->base = devm_platform_ioremap_resource(pdev, 0);
507 	if (IS_ERR(miic->base))
508 		return PTR_ERR(miic->base);
509 
510 	ret = devm_pm_runtime_enable(dev);
511 	if (ret < 0)
512 		return ret;
513 
514 	ret = pm_runtime_resume_and_get(dev);
515 	if (ret < 0)
516 		return ret;
517 
518 	ret = miic_init_hw(miic, mode_cfg);
519 	if (ret)
520 		goto disable_runtime_pm;
521 
522 	/* miic_create() relies on that fact that data are attached to the
523 	 * platform device to determine if the driver is ready so this needs to
524 	 * be the last thing to be done after everything is initialized
525 	 * properly.
526 	 */
527 	platform_set_drvdata(pdev, miic);
528 
529 	return 0;
530 
531 disable_runtime_pm:
532 	pm_runtime_put(dev);
533 
534 	return ret;
535 }
536 
537 static void miic_remove(struct platform_device *pdev)
538 {
539 	pm_runtime_put(&pdev->dev);
540 }
541 
542 static const struct of_device_id miic_of_mtable[] = {
543 	{ .compatible = "renesas,rzn1-miic" },
544 	{ /* sentinel */ },
545 };
546 MODULE_DEVICE_TABLE(of, miic_of_mtable);
547 
548 static struct platform_driver miic_driver = {
549 	.driver = {
550 		.name	 = "rzn1_miic",
551 		.suppress_bind_attrs = true,
552 		.of_match_table = miic_of_mtable,
553 	},
554 	.probe = miic_probe,
555 	.remove = miic_remove,
556 };
557 module_platform_driver(miic_driver);
558 
559 MODULE_LICENSE("GPL");
560 MODULE_DESCRIPTION("Renesas MII converter PCS driver");
561 MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
562