xref: /linux/drivers/net/pcs/pcs-rzn1-miic.c (revision 861d10f09250537e6eb0cfd3b6fcee8ada8b482f)
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/array_size.h>
9 #include <linux/bits.h>
10 #include <linux/clk.h>
11 #include <linux/device.h>
12 #include <linux/mdio.h>
13 #include <linux/of.h>
14 #include <linux/of_platform.h>
15 #include <linux/pcs-rzn1-miic.h>
16 #include <linux/phylink.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm_runtime.h>
19 #include <dt-bindings/net/pcs-rzn1-miic.h>
20 
21 #define MIIC_PRCMD			0x0
22 #define MIIC_ESID_CODE			0x4
23 
24 #define MIIC_MODCTRL			0x8
25 #define MIIC_MODCTRL_SW_MODE		GENMASK(4, 0)
26 
27 #define MIIC_CONVCTRL(port)		(0x100 + (port) * 4)
28 
29 #define MIIC_CONVCTRL_CONV_SPEED	GENMASK(1, 0)
30 #define CONV_MODE_10MBPS		0
31 #define CONV_MODE_100MBPS		1
32 #define CONV_MODE_1000MBPS		2
33 
34 #define MIIC_CONVCTRL_CONV_MODE		GENMASK(3, 2)
35 #define CONV_MODE_MII			0
36 #define CONV_MODE_RMII			1
37 #define CONV_MODE_RGMII			2
38 
39 #define MIIC_CONVCTRL_FULLD		BIT(8)
40 #define MIIC_CONVCTRL_RGMII_LINK	BIT(12)
41 #define MIIC_CONVCTRL_RGMII_DUPLEX	BIT(13)
42 #define MIIC_CONVCTRL_RGMII_SPEED	GENMASK(15, 14)
43 
44 #define MIIC_CONVRST			0x114
45 #define MIIC_CONVRST_PHYIF_RST(port)	BIT(port)
46 #define MIIC_CONVRST_PHYIF_RST_MASK	GENMASK(4, 0)
47 
48 #define MIIC_SWCTRL			0x304
49 #define MIIC_SWDUPC			0x308
50 
51 #define MIIC_MAX_NR_PORTS		5
52 
53 #define MIIC_MODCTRL_CONF_CONV_NUM	6
54 #define MIIC_MODCTRL_CONF_NONE		-1
55 
56 /**
57  * struct modctrl_match - Matching table entry for  convctrl configuration
58  *			  See section 8.2.1 of manual.
59  * @mode_cfg: Configuration value for convctrl
60  * @conv: Configuration of ethernet port muxes. First index is SWITCH_PORTIN,
61  *	  then index 1 - 5 are CONV1 - CONV5.
62  */
63 struct modctrl_match {
64 	u32 mode_cfg;
65 	u8 conv[MIIC_MODCTRL_CONF_CONV_NUM];
66 };
67 
68 static struct modctrl_match modctrl_match_table[] = {
69 	{0x0, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
70 	       MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
71 	{0x1, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
72 	       MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
73 	{0x2, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
74 	       MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
75 	{0x3, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
76 	       MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}},
77 
78 	{0x8, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
79 	       MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
80 	{0x9, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
81 	       MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
82 	{0xA, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
83 	       MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
84 	{0xB, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
85 	       MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}},
86 
87 	{0x10, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
88 		MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
89 	{0x11, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
90 		MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
91 	{0x12, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
92 		MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
93 	{0x13, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
94 		MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}}
95 };
96 
97 static const char * const conf_to_string[] = {
98 	[MIIC_GMAC1_PORT]	= "GMAC1_PORT",
99 	[MIIC_GMAC2_PORT]	= "GMAC2_PORT",
100 	[MIIC_RTOS_PORT]	= "RTOS_PORT",
101 	[MIIC_SERCOS_PORTA]	= "SERCOS_PORTA",
102 	[MIIC_SERCOS_PORTB]	= "SERCOS_PORTB",
103 	[MIIC_ETHERCAT_PORTA]	= "ETHERCAT_PORTA",
104 	[MIIC_ETHERCAT_PORTB]	= "ETHERCAT_PORTB",
105 	[MIIC_ETHERCAT_PORTC]	= "ETHERCAT_PORTC",
106 	[MIIC_SWITCH_PORTA]	= "SWITCH_PORTA",
107 	[MIIC_SWITCH_PORTB]	= "SWITCH_PORTB",
108 	[MIIC_SWITCH_PORTC]	= "SWITCH_PORTC",
109 	[MIIC_SWITCH_PORTD]	= "SWITCH_PORTD",
110 	[MIIC_HSR_PORTA]	= "HSR_PORTA",
111 	[MIIC_HSR_PORTB]	= "HSR_PORTB",
112 };
113 
114 static const char *index_to_string[MIIC_MODCTRL_CONF_CONV_NUM] = {
115 	"SWITCH_PORTIN",
116 	"CONV1",
117 	"CONV2",
118 	"CONV3",
119 	"CONV4",
120 	"CONV5",
121 };
122 
123 /**
124  * struct miic - MII converter structure
125  * @base: base address of the MII converter
126  * @dev: Device associated to the MII converter
127  * @lock: Lock used for read-modify-write access
128  */
129 struct miic {
130 	void __iomem *base;
131 	struct device *dev;
132 	spinlock_t lock;
133 };
134 
135 /**
136  * struct miic_port - Per port MII converter struct
137  * @miic: backiling to MII converter structure
138  * @pcs: PCS structure associated to the port
139  * @port: port number
140  * @interface: interface mode of the port
141  */
142 struct miic_port {
143 	struct miic *miic;
144 	struct phylink_pcs pcs;
145 	int port;
146 	phy_interface_t interface;
147 };
148 
149 static struct miic_port *phylink_pcs_to_miic_port(struct phylink_pcs *pcs)
150 {
151 	return container_of(pcs, struct miic_port, pcs);
152 }
153 
154 static void miic_reg_writel(struct miic *miic, int offset, u32 value)
155 {
156 	writel(value, miic->base + offset);
157 }
158 
159 static u32 miic_reg_readl(struct miic *miic, int offset)
160 {
161 	return readl(miic->base + offset);
162 }
163 
164 static void miic_reg_rmw(struct miic *miic, int offset, u32 mask, u32 val)
165 {
166 	u32 reg;
167 
168 	spin_lock(&miic->lock);
169 
170 	reg = miic_reg_readl(miic, offset);
171 	reg &= ~mask;
172 	reg |= val;
173 	miic_reg_writel(miic, offset, reg);
174 
175 	spin_unlock(&miic->lock);
176 }
177 
178 static void miic_converter_enable(struct miic *miic, int port, int enable)
179 {
180 	u32 val = 0;
181 
182 	if (enable)
183 		val = MIIC_CONVRST_PHYIF_RST(port);
184 
185 	miic_reg_rmw(miic, MIIC_CONVRST, MIIC_CONVRST_PHYIF_RST(port), val);
186 }
187 
188 static int miic_config(struct phylink_pcs *pcs, unsigned int neg_mode,
189 		       phy_interface_t interface,
190 		       const unsigned long *advertising, bool permit)
191 {
192 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
193 	struct miic *miic = miic_port->miic;
194 	u32 speed, conv_mode, val, mask;
195 	int port = miic_port->port;
196 
197 	switch (interface) {
198 	case PHY_INTERFACE_MODE_RMII:
199 		conv_mode = CONV_MODE_RMII;
200 		speed = CONV_MODE_100MBPS;
201 		break;
202 	case PHY_INTERFACE_MODE_RGMII:
203 	case PHY_INTERFACE_MODE_RGMII_ID:
204 	case PHY_INTERFACE_MODE_RGMII_TXID:
205 	case PHY_INTERFACE_MODE_RGMII_RXID:
206 		conv_mode = CONV_MODE_RGMII;
207 		speed = CONV_MODE_1000MBPS;
208 		break;
209 	case PHY_INTERFACE_MODE_MII:
210 		conv_mode = CONV_MODE_MII;
211 		/* When in MII mode, speed should be set to 0 (which is actually
212 		 * CONV_MODE_10MBPS)
213 		 */
214 		speed = CONV_MODE_10MBPS;
215 		break;
216 	default:
217 		return -EOPNOTSUPP;
218 	}
219 
220 	val = FIELD_PREP(MIIC_CONVCTRL_CONV_MODE, conv_mode);
221 	mask = MIIC_CONVCTRL_CONV_MODE;
222 
223 	/* Update speed only if we are going to change the interface because
224 	 * the link might already be up and it would break it if the speed is
225 	 * changed.
226 	 */
227 	if (interface != miic_port->interface) {
228 		val |= FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, speed);
229 		mask |= MIIC_CONVCTRL_CONV_SPEED;
230 		miic_port->interface = interface;
231 	}
232 
233 	miic_reg_rmw(miic, MIIC_CONVCTRL(port), mask, val);
234 	miic_converter_enable(miic, miic_port->port, 1);
235 
236 	return 0;
237 }
238 
239 static void miic_link_up(struct phylink_pcs *pcs, unsigned int neg_mode,
240 			 phy_interface_t interface, int speed, int duplex)
241 {
242 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
243 	struct miic *miic = miic_port->miic;
244 	u32 conv_speed = 0, val = 0;
245 	int port = miic_port->port;
246 
247 	if (duplex == DUPLEX_FULL)
248 		val |= MIIC_CONVCTRL_FULLD;
249 
250 	/* No speed in MII through-mode */
251 	if (interface != PHY_INTERFACE_MODE_MII) {
252 		switch (speed) {
253 		case SPEED_1000:
254 			conv_speed = CONV_MODE_1000MBPS;
255 			break;
256 		case SPEED_100:
257 			conv_speed = CONV_MODE_100MBPS;
258 			break;
259 		case SPEED_10:
260 			conv_speed = CONV_MODE_10MBPS;
261 			break;
262 		default:
263 			return;
264 		}
265 	}
266 
267 	val |= FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, conv_speed);
268 
269 	miic_reg_rmw(miic, MIIC_CONVCTRL(port),
270 		     (MIIC_CONVCTRL_CONV_SPEED | MIIC_CONVCTRL_FULLD), val);
271 }
272 
273 static int miic_pre_init(struct phylink_pcs *pcs)
274 {
275 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
276 	struct miic *miic = miic_port->miic;
277 	u32 val, mask;
278 
279 	/* Start RX clock if required */
280 	if (pcs->rxc_always_on) {
281 		/* In MII through mode, the clock signals will be driven by the
282 		 * external PHY, which might not be initialized yet. Set RMII
283 		 * as default mode to ensure that a reference clock signal is
284 		 * generated.
285 		 */
286 		miic_port->interface = PHY_INTERFACE_MODE_RMII;
287 
288 		val = FIELD_PREP(MIIC_CONVCTRL_CONV_MODE, CONV_MODE_RMII) |
289 		      FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, CONV_MODE_100MBPS);
290 		mask = MIIC_CONVCTRL_CONV_MODE | MIIC_CONVCTRL_CONV_SPEED;
291 
292 		miic_reg_rmw(miic, MIIC_CONVCTRL(miic_port->port), mask, val);
293 
294 		miic_converter_enable(miic, miic_port->port, 1);
295 	}
296 
297 	return 0;
298 }
299 
300 static const struct phylink_pcs_ops miic_phylink_ops = {
301 	.pcs_config = miic_config,
302 	.pcs_link_up = miic_link_up,
303 	.pcs_pre_init = miic_pre_init,
304 };
305 
306 struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
307 {
308 	struct platform_device *pdev;
309 	struct miic_port *miic_port;
310 	struct device_node *pcs_np;
311 	struct miic *miic;
312 	u32 port;
313 
314 	if (!of_device_is_available(np))
315 		return ERR_PTR(-ENODEV);
316 
317 	if (of_property_read_u32(np, "reg", &port))
318 		return ERR_PTR(-EINVAL);
319 
320 	if (port > MIIC_MAX_NR_PORTS || port < 1)
321 		return ERR_PTR(-EINVAL);
322 
323 	/* The PCS pdev is attached to the parent node */
324 	pcs_np = of_get_parent(np);
325 	if (!pcs_np)
326 		return ERR_PTR(-ENODEV);
327 
328 	if (!of_device_is_available(pcs_np)) {
329 		of_node_put(pcs_np);
330 		return ERR_PTR(-ENODEV);
331 	}
332 
333 	pdev = of_find_device_by_node(pcs_np);
334 	of_node_put(pcs_np);
335 	if (!pdev || !platform_get_drvdata(pdev)) {
336 		if (pdev)
337 			put_device(&pdev->dev);
338 		return ERR_PTR(-EPROBE_DEFER);
339 	}
340 
341 	miic_port = kzalloc(sizeof(*miic_port), GFP_KERNEL);
342 	if (!miic_port) {
343 		put_device(&pdev->dev);
344 		return ERR_PTR(-ENOMEM);
345 	}
346 
347 	miic = platform_get_drvdata(pdev);
348 	device_link_add(dev, miic->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
349 	put_device(&pdev->dev);
350 
351 	miic_port->miic = miic;
352 	miic_port->port = port - 1;
353 	miic_port->pcs.ops = &miic_phylink_ops;
354 
355 	phy_interface_set_rgmii(miic_port->pcs.supported_interfaces);
356 	__set_bit(PHY_INTERFACE_MODE_RMII, miic_port->pcs.supported_interfaces);
357 	__set_bit(PHY_INTERFACE_MODE_MII, miic_port->pcs.supported_interfaces);
358 
359 	return &miic_port->pcs;
360 }
361 EXPORT_SYMBOL(miic_create);
362 
363 void miic_destroy(struct phylink_pcs *pcs)
364 {
365 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
366 
367 	miic_converter_enable(miic_port->miic, miic_port->port, 0);
368 	kfree(miic_port);
369 }
370 EXPORT_SYMBOL(miic_destroy);
371 
372 static int miic_init_hw(struct miic *miic, u32 cfg_mode)
373 {
374 	int port;
375 
376 	/* Unlock write access to accessory registers (cf datasheet). If this
377 	 * is going to be used in conjunction with the Cortex-M3, this sequence
378 	 * will have to be moved in register write
379 	 */
380 	miic_reg_writel(miic, MIIC_PRCMD, 0x00A5);
381 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
382 	miic_reg_writel(miic, MIIC_PRCMD, 0xFFFE);
383 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
384 
385 	miic_reg_writel(miic, MIIC_MODCTRL,
386 			FIELD_PREP(MIIC_MODCTRL_SW_MODE, cfg_mode));
387 
388 	for (port = 0; port < MIIC_MAX_NR_PORTS; port++) {
389 		miic_converter_enable(miic, port, 0);
390 		/* Disable speed/duplex control from these registers, datasheet
391 		 * says switch registers should be used to setup switch port
392 		 * speed and duplex.
393 		 */
394 		miic_reg_writel(miic, MIIC_SWCTRL, 0x0);
395 		miic_reg_writel(miic, MIIC_SWDUPC, 0x0);
396 	}
397 
398 	return 0;
399 }
400 
401 static bool miic_modctrl_match(s8 table_val[MIIC_MODCTRL_CONF_CONV_NUM],
402 			       s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM])
403 {
404 	int i;
405 
406 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
407 		if (dt_val[i] == MIIC_MODCTRL_CONF_NONE)
408 			continue;
409 
410 		if (dt_val[i] != table_val[i])
411 			return false;
412 	}
413 
414 	return true;
415 }
416 
417 static void miic_dump_conf(struct device *dev,
418 			   s8 conf[MIIC_MODCTRL_CONF_CONV_NUM])
419 {
420 	const char *conf_name;
421 	int i;
422 
423 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
424 		if (conf[i] != MIIC_MODCTRL_CONF_NONE)
425 			conf_name = conf_to_string[conf[i]];
426 		else
427 			conf_name = "NONE";
428 
429 		dev_err(dev, "%s: %s\n", index_to_string[i], conf_name);
430 	}
431 }
432 
433 static int miic_match_dt_conf(struct device *dev,
434 			      s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM],
435 			      u32 *mode_cfg)
436 {
437 	struct modctrl_match *table_entry;
438 	int i;
439 
440 	for (i = 0; i < ARRAY_SIZE(modctrl_match_table); i++) {
441 		table_entry = &modctrl_match_table[i];
442 
443 		if (miic_modctrl_match(table_entry->conv, dt_val)) {
444 			*mode_cfg = table_entry->mode_cfg;
445 			return 0;
446 		}
447 	}
448 
449 	dev_err(dev, "Failed to apply requested configuration\n");
450 	miic_dump_conf(dev, dt_val);
451 
452 	return -EINVAL;
453 }
454 
455 static int miic_parse_dt(struct device *dev, u32 *mode_cfg)
456 {
457 	s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM];
458 	struct device_node *np = dev->of_node;
459 	struct device_node *conv;
460 	u32 conf;
461 	int port;
462 
463 	memset(dt_val, MIIC_MODCTRL_CONF_NONE, sizeof(dt_val));
464 
465 	if (of_property_read_u32(np, "renesas,miic-switch-portin", &conf) == 0)
466 		dt_val[0] = conf;
467 
468 	for_each_available_child_of_node(np, conv) {
469 		if (of_property_read_u32(conv, "reg", &port))
470 			continue;
471 
472 		if (of_property_read_u32(conv, "renesas,miic-input", &conf) == 0)
473 			dt_val[port] = conf;
474 	}
475 
476 	return miic_match_dt_conf(dev, dt_val, mode_cfg);
477 }
478 
479 static int miic_probe(struct platform_device *pdev)
480 {
481 	struct device *dev = &pdev->dev;
482 	struct miic *miic;
483 	u32 mode_cfg;
484 	int ret;
485 
486 	ret = miic_parse_dt(dev, &mode_cfg);
487 	if (ret < 0)
488 		return ret;
489 
490 	miic = devm_kzalloc(dev, sizeof(*miic), GFP_KERNEL);
491 	if (!miic)
492 		return -ENOMEM;
493 
494 	spin_lock_init(&miic->lock);
495 	miic->dev = dev;
496 	miic->base = devm_platform_ioremap_resource(pdev, 0);
497 	if (IS_ERR(miic->base))
498 		return PTR_ERR(miic->base);
499 
500 	ret = devm_pm_runtime_enable(dev);
501 	if (ret < 0)
502 		return ret;
503 
504 	ret = pm_runtime_resume_and_get(dev);
505 	if (ret < 0)
506 		return ret;
507 
508 	ret = miic_init_hw(miic, mode_cfg);
509 	if (ret)
510 		goto disable_runtime_pm;
511 
512 	/* miic_create() relies on that fact that data are attached to the
513 	 * platform device to determine if the driver is ready so this needs to
514 	 * be the last thing to be done after everything is initialized
515 	 * properly.
516 	 */
517 	platform_set_drvdata(pdev, miic);
518 
519 	return 0;
520 
521 disable_runtime_pm:
522 	pm_runtime_put(dev);
523 
524 	return ret;
525 }
526 
527 static void miic_remove(struct platform_device *pdev)
528 {
529 	pm_runtime_put(&pdev->dev);
530 }
531 
532 static const struct of_device_id miic_of_mtable[] = {
533 	{ .compatible = "renesas,rzn1-miic" },
534 	{ /* sentinel */ }
535 };
536 MODULE_DEVICE_TABLE(of, miic_of_mtable);
537 
538 static struct platform_driver miic_driver = {
539 	.driver = {
540 		.name	 = "rzn1_miic",
541 		.suppress_bind_attrs = true,
542 		.of_match_table = miic_of_mtable,
543 	},
544 	.probe = miic_probe,
545 	.remove = miic_remove,
546 };
547 module_platform_driver(miic_driver);
548 
549 MODULE_LICENSE("GPL");
550 MODULE_DESCRIPTION("Renesas MII converter PCS driver");
551 MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
552