xref: /linux/drivers/net/pcs/pcs-rzn1-miic.c (revision 320fefa9e2edc67011e235ea1d50f0d00ddfe004)
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/pm_runtime.h>
16 #include <dt-bindings/net/pcs-rzn1-miic.h>
17 
18 #define MIIC_PRCMD			0x0
19 #define MIIC_ESID_CODE			0x4
20 
21 #define MIIC_MODCTRL			0x20
22 #define MIIC_MODCTRL_SW_MODE		GENMASK(4, 0)
23 
24 #define MIIC_CONVCTRL(port)		(0x100 + (port) * 4)
25 
26 #define MIIC_CONVCTRL_CONV_SPEED	GENMASK(1, 0)
27 #define CONV_MODE_10MBPS		0
28 #define CONV_MODE_100MBPS		1
29 #define CONV_MODE_1000MBPS		2
30 
31 #define MIIC_CONVCTRL_CONV_MODE		GENMASK(3, 2)
32 #define CONV_MODE_MII			0
33 #define CONV_MODE_RMII			1
34 #define CONV_MODE_RGMII			2
35 
36 #define MIIC_CONVCTRL_FULLD		BIT(8)
37 #define MIIC_CONVCTRL_RGMII_LINK	BIT(12)
38 #define MIIC_CONVCTRL_RGMII_DUPLEX	BIT(13)
39 #define MIIC_CONVCTRL_RGMII_SPEED	GENMASK(15, 14)
40 
41 #define MIIC_CONVRST			0x114
42 #define MIIC_CONVRST_PHYIF_RST(port)	BIT(port)
43 #define MIIC_CONVRST_PHYIF_RST_MASK	GENMASK(4, 0)
44 
45 #define MIIC_SWCTRL			0x304
46 #define MIIC_SWDUPC			0x308
47 
48 #define MIIC_MAX_NR_PORTS		5
49 
50 #define MIIC_MODCTRL_CONF_CONV_NUM	6
51 #define MIIC_MODCTRL_CONF_NONE		-1
52 
53 /**
54  * struct modctrl_match - Matching table entry for  convctrl configuration
55  *			  See section 8.2.1 of manual.
56  * @mode_cfg: Configuration value for convctrl
57  * @conv: Configuration of ethernet port muxes. First index is SWITCH_PORTIN,
58  *	  then index 1 - 5 are CONV1 - CONV5.
59  */
60 struct modctrl_match {
61 	u32 mode_cfg;
62 	u8 conv[MIIC_MODCTRL_CONF_CONV_NUM];
63 };
64 
65 static struct modctrl_match modctrl_match_table[] = {
66 	{0x0, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
67 	       MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
68 	{0x1, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
69 	       MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
70 	{0x2, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
71 	       MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
72 	{0x3, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
73 	       MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}},
74 
75 	{0x8, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
76 	       MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
77 	{0x9, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
78 	       MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
79 	{0xA, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
80 	       MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
81 	{0xB, {MIIC_RTOS_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
82 	       MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}},
83 
84 	{0x10, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
85 		MIIC_SWITCH_PORTC, MIIC_SERCOS_PORTB, MIIC_SERCOS_PORTA}},
86 	{0x11, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
87 		MIIC_SWITCH_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
88 	{0x12, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
89 		MIIC_ETHERCAT_PORTC, MIIC_ETHERCAT_PORTB, MIIC_ETHERCAT_PORTA}},
90 	{0x13, {MIIC_GMAC2_PORT, MIIC_GMAC1_PORT, MIIC_SWITCH_PORTD,
91 		MIIC_SWITCH_PORTC, MIIC_SWITCH_PORTB, MIIC_SWITCH_PORTA}}
92 };
93 
94 static const char * const conf_to_string[] = {
95 	[MIIC_GMAC1_PORT]	= "GMAC1_PORT",
96 	[MIIC_GMAC2_PORT]	= "GMAC2_PORT",
97 	[MIIC_RTOS_PORT]	= "RTOS_PORT",
98 	[MIIC_SERCOS_PORTA]	= "SERCOS_PORTA",
99 	[MIIC_SERCOS_PORTB]	= "SERCOS_PORTB",
100 	[MIIC_ETHERCAT_PORTA]	= "ETHERCAT_PORTA",
101 	[MIIC_ETHERCAT_PORTB]	= "ETHERCAT_PORTB",
102 	[MIIC_ETHERCAT_PORTC]	= "ETHERCAT_PORTC",
103 	[MIIC_SWITCH_PORTA]	= "SWITCH_PORTA",
104 	[MIIC_SWITCH_PORTB]	= "SWITCH_PORTB",
105 	[MIIC_SWITCH_PORTC]	= "SWITCH_PORTC",
106 	[MIIC_SWITCH_PORTD]	= "SWITCH_PORTD",
107 	[MIIC_HSR_PORTA]	= "HSR_PORTA",
108 	[MIIC_HSR_PORTB]	= "HSR_PORTB",
109 };
110 
111 static const char *index_to_string[MIIC_MODCTRL_CONF_CONV_NUM] = {
112 	"SWITCH_PORTIN",
113 	"CONV1",
114 	"CONV2",
115 	"CONV3",
116 	"CONV4",
117 	"CONV5",
118 };
119 
120 /**
121  * struct miic - MII converter structure
122  * @base: base address of the MII converter
123  * @dev: Device associated to the MII converter
124  * @clks: Clocks used for this device
125  * @nclk: Number of clocks
126  * @lock: Lock used for read-modify-write access
127  */
128 struct miic {
129 	void __iomem *base;
130 	struct device *dev;
131 	struct clk_bulk_data *clks;
132 	int nclk;
133 	spinlock_t lock;
134 };
135 
136 /**
137  * struct miic_port - Per port MII converter struct
138  * @miic: backiling to MII converter structure
139  * @pcs: PCS structure associated to the port
140  * @port: port number
141  * @interface: interface mode of the port
142  */
143 struct miic_port {
144 	struct miic *miic;
145 	struct phylink_pcs pcs;
146 	int port;
147 	phy_interface_t interface;
148 };
149 
150 static struct miic_port *phylink_pcs_to_miic_port(struct phylink_pcs *pcs)
151 {
152 	return container_of(pcs, struct miic_port, pcs);
153 }
154 
155 static void miic_reg_writel(struct miic *miic, int offset, u32 value)
156 {
157 	writel(value, miic->base + offset);
158 }
159 
160 static u32 miic_reg_readl(struct miic *miic, int offset)
161 {
162 	return readl(miic->base + offset);
163 }
164 
165 static void miic_reg_rmw(struct miic *miic, int offset, u32 mask, u32 val)
166 {
167 	u32 reg;
168 
169 	spin_lock(&miic->lock);
170 
171 	reg = miic_reg_readl(miic, offset);
172 	reg &= ~mask;
173 	reg |= val;
174 	miic_reg_writel(miic, offset, reg);
175 
176 	spin_unlock(&miic->lock);
177 }
178 
179 static void miic_converter_enable(struct miic *miic, int port, int enable)
180 {
181 	u32 val = 0;
182 
183 	if (enable)
184 		val = MIIC_CONVRST_PHYIF_RST(port);
185 
186 	miic_reg_rmw(miic, MIIC_CONVRST, MIIC_CONVRST_PHYIF_RST(port), val);
187 }
188 
189 static int miic_config(struct phylink_pcs *pcs, unsigned int mode,
190 		       phy_interface_t interface,
191 		       const unsigned long *advertising, bool permit)
192 {
193 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
194 	struct miic *miic = miic_port->miic;
195 	u32 speed, conv_mode, val, mask;
196 	int port = miic_port->port;
197 
198 	switch (interface) {
199 	case PHY_INTERFACE_MODE_RMII:
200 		conv_mode = CONV_MODE_RMII;
201 		speed = CONV_MODE_100MBPS;
202 		break;
203 	case PHY_INTERFACE_MODE_RGMII:
204 	case PHY_INTERFACE_MODE_RGMII_ID:
205 	case PHY_INTERFACE_MODE_RGMII_TXID:
206 	case PHY_INTERFACE_MODE_RGMII_RXID:
207 		conv_mode = CONV_MODE_RGMII;
208 		speed = CONV_MODE_1000MBPS;
209 		break;
210 	case PHY_INTERFACE_MODE_MII:
211 		conv_mode = CONV_MODE_MII;
212 		/* When in MII mode, speed should be set to 0 (which is actually
213 		 * CONV_MODE_10MBPS)
214 		 */
215 		speed = CONV_MODE_10MBPS;
216 		break;
217 	default:
218 		return -EOPNOTSUPP;
219 	}
220 
221 	val = FIELD_PREP(MIIC_CONVCTRL_CONV_MODE, conv_mode);
222 	mask = MIIC_CONVCTRL_CONV_MODE;
223 
224 	/* Update speed only if we are going to change the interface because
225 	 * the link might already be up and it would break it if the speed is
226 	 * changed.
227 	 */
228 	if (interface != miic_port->interface) {
229 		val |= FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, speed);
230 		mask |= MIIC_CONVCTRL_CONV_SPEED;
231 		miic_port->interface = interface;
232 	}
233 
234 	miic_reg_rmw(miic, MIIC_CONVCTRL(port), mask, val);
235 	miic_converter_enable(miic_port->miic, miic_port->port, 1);
236 
237 	return 0;
238 }
239 
240 static void miic_link_up(struct phylink_pcs *pcs, unsigned int mode,
241 			 phy_interface_t interface, int speed, int duplex)
242 {
243 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
244 	struct miic *miic = miic_port->miic;
245 	u32 conv_speed = 0, val = 0;
246 	int port = miic_port->port;
247 
248 	if (duplex == DUPLEX_FULL)
249 		val |= MIIC_CONVCTRL_FULLD;
250 
251 	/* No speed in MII through-mode */
252 	if (interface != PHY_INTERFACE_MODE_MII) {
253 		switch (speed) {
254 		case SPEED_1000:
255 			conv_speed = CONV_MODE_1000MBPS;
256 			break;
257 		case SPEED_100:
258 			conv_speed = CONV_MODE_100MBPS;
259 			break;
260 		case SPEED_10:
261 			conv_speed = CONV_MODE_10MBPS;
262 			break;
263 		default:
264 			return;
265 		}
266 	}
267 
268 	val |= FIELD_PREP(MIIC_CONVCTRL_CONV_SPEED, conv_speed);
269 
270 	miic_reg_rmw(miic, MIIC_CONVCTRL(port),
271 		     (MIIC_CONVCTRL_CONV_SPEED | MIIC_CONVCTRL_FULLD), val);
272 }
273 
274 static int miic_validate(struct phylink_pcs *pcs, unsigned long *supported,
275 			 const struct phylink_link_state *state)
276 {
277 	if (phy_interface_mode_is_rgmii(state->interface) ||
278 	    state->interface == PHY_INTERFACE_MODE_RMII ||
279 	    state->interface == PHY_INTERFACE_MODE_MII)
280 		return 1;
281 
282 	return -EINVAL;
283 }
284 
285 static const struct phylink_pcs_ops miic_phylink_ops = {
286 	.pcs_validate = miic_validate,
287 	.pcs_config = miic_config,
288 	.pcs_link_up = miic_link_up,
289 };
290 
291 struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
292 {
293 	struct platform_device *pdev;
294 	struct miic_port *miic_port;
295 	struct device_node *pcs_np;
296 	struct miic *miic;
297 	u32 port;
298 
299 	if (!of_device_is_available(np))
300 		return ERR_PTR(-ENODEV);
301 
302 	if (of_property_read_u32(np, "reg", &port))
303 		return ERR_PTR(-EINVAL);
304 
305 	if (port > MIIC_MAX_NR_PORTS || port < 1)
306 		return ERR_PTR(-EINVAL);
307 
308 	/* The PCS pdev is attached to the parent node */
309 	pcs_np = of_get_parent(np);
310 	if (!pcs_np)
311 		return ERR_PTR(-ENODEV);
312 
313 	if (!of_device_is_available(pcs_np)) {
314 		of_node_put(pcs_np);
315 		return ERR_PTR(-ENODEV);
316 	}
317 
318 	pdev = of_find_device_by_node(pcs_np);
319 	of_node_put(pcs_np);
320 	if (!pdev || !platform_get_drvdata(pdev))
321 		return ERR_PTR(-EPROBE_DEFER);
322 
323 	miic_port = kzalloc(sizeof(*miic_port), GFP_KERNEL);
324 	if (!miic_port)
325 		return ERR_PTR(-ENOMEM);
326 
327 	miic = platform_get_drvdata(pdev);
328 	device_link_add(dev, miic->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
329 
330 	miic_port->miic = miic;
331 	miic_port->port = port - 1;
332 	miic_port->pcs.ops = &miic_phylink_ops;
333 
334 	return &miic_port->pcs;
335 }
336 EXPORT_SYMBOL(miic_create);
337 
338 void miic_destroy(struct phylink_pcs *pcs)
339 {
340 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
341 
342 	miic_converter_enable(miic_port->miic, miic_port->port, 0);
343 	kfree(miic_port);
344 }
345 EXPORT_SYMBOL(miic_destroy);
346 
347 static int miic_init_hw(struct miic *miic, u32 cfg_mode)
348 {
349 	int port;
350 
351 	/* Unlock write access to accessory registers (cf datasheet). If this
352 	 * is going to be used in conjunction with the Cortex-M3, this sequence
353 	 * will have to be moved in register write
354 	 */
355 	miic_reg_writel(miic, MIIC_PRCMD, 0x00A5);
356 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
357 	miic_reg_writel(miic, MIIC_PRCMD, 0xFFFE);
358 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
359 
360 	miic_reg_writel(miic, MIIC_MODCTRL,
361 			FIELD_PREP(MIIC_MODCTRL_SW_MODE, cfg_mode));
362 
363 	for (port = 0; port < MIIC_MAX_NR_PORTS; port++) {
364 		miic_converter_enable(miic, port, 0);
365 		/* Disable speed/duplex control from these registers, datasheet
366 		 * says switch registers should be used to setup switch port
367 		 * speed and duplex.
368 		 */
369 		miic_reg_writel(miic, MIIC_SWCTRL, 0x0);
370 		miic_reg_writel(miic, MIIC_SWDUPC, 0x0);
371 	}
372 
373 	return 0;
374 }
375 
376 static bool miic_modctrl_match(s8 table_val[MIIC_MODCTRL_CONF_CONV_NUM],
377 			       s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM])
378 {
379 	int i;
380 
381 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
382 		if (dt_val[i] == MIIC_MODCTRL_CONF_NONE)
383 			continue;
384 
385 		if (dt_val[i] != table_val[i])
386 			return false;
387 	}
388 
389 	return true;
390 }
391 
392 static void miic_dump_conf(struct device *dev,
393 			   s8 conf[MIIC_MODCTRL_CONF_CONV_NUM])
394 {
395 	const char *conf_name;
396 	int i;
397 
398 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
399 		if (conf[i] != MIIC_MODCTRL_CONF_NONE)
400 			conf_name = conf_to_string[conf[i]];
401 		else
402 			conf_name = "NONE";
403 
404 		dev_err(dev, "%s: %s\n", index_to_string[i], conf_name);
405 	}
406 }
407 
408 static int miic_match_dt_conf(struct device *dev,
409 			      s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM],
410 			      u32 *mode_cfg)
411 {
412 	struct modctrl_match *table_entry;
413 	int i;
414 
415 	for (i = 0; i < ARRAY_SIZE(modctrl_match_table); i++) {
416 		table_entry = &modctrl_match_table[i];
417 
418 		if (miic_modctrl_match(table_entry->conv, dt_val)) {
419 			*mode_cfg = table_entry->mode_cfg;
420 			return 0;
421 		}
422 	}
423 
424 	dev_err(dev, "Failed to apply requested configuration\n");
425 	miic_dump_conf(dev, dt_val);
426 
427 	return -EINVAL;
428 }
429 
430 static int miic_parse_dt(struct device *dev, u32 *mode_cfg)
431 {
432 	s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM];
433 	struct device_node *np = dev->of_node;
434 	struct device_node *conv;
435 	u32 conf;
436 	int port;
437 
438 	memset(dt_val, MIIC_MODCTRL_CONF_NONE, sizeof(dt_val));
439 
440 	if (of_property_read_u32(np, "renesas,miic-switch-portin", &conf) == 0)
441 		dt_val[0] = conf;
442 
443 	for_each_child_of_node(np, conv) {
444 		if (of_property_read_u32(conv, "reg", &port))
445 			continue;
446 
447 		if (!of_device_is_available(conv))
448 			continue;
449 
450 		if (of_property_read_u32(conv, "renesas,miic-input", &conf) == 0)
451 			dt_val[port] = conf;
452 	}
453 
454 	return miic_match_dt_conf(dev, dt_val, mode_cfg);
455 }
456 
457 static int miic_probe(struct platform_device *pdev)
458 {
459 	struct device *dev = &pdev->dev;
460 	struct miic *miic;
461 	u32 mode_cfg;
462 	int ret;
463 
464 	ret = miic_parse_dt(dev, &mode_cfg);
465 	if (ret < 0)
466 		return ret;
467 
468 	miic = devm_kzalloc(dev, sizeof(*miic), GFP_KERNEL);
469 	if (!miic)
470 		return -ENOMEM;
471 
472 	spin_lock_init(&miic->lock);
473 	miic->dev = dev;
474 	miic->base = devm_platform_ioremap_resource(pdev, 0);
475 	if (IS_ERR(miic->base))
476 		return PTR_ERR(miic->base);
477 
478 	ret = devm_pm_runtime_enable(dev);
479 	if (ret < 0)
480 		return ret;
481 
482 	ret = pm_runtime_resume_and_get(dev);
483 	if (ret < 0)
484 		return ret;
485 
486 	ret = miic_init_hw(miic, mode_cfg);
487 	if (ret)
488 		goto disable_runtime_pm;
489 
490 	/* miic_create() relies on that fact that data are attached to the
491 	 * platform device to determine if the driver is ready so this needs to
492 	 * be the last thing to be done after everything is initialized
493 	 * properly.
494 	 */
495 	platform_set_drvdata(pdev, miic);
496 
497 	return 0;
498 
499 disable_runtime_pm:
500 	pm_runtime_put(dev);
501 
502 	return ret;
503 }
504 
505 static int miic_remove(struct platform_device *pdev)
506 {
507 	pm_runtime_put(&pdev->dev);
508 
509 	return 0;
510 }
511 
512 static const struct of_device_id miic_of_mtable[] = {
513 	{ .compatible = "renesas,rzn1-miic" },
514 	{ /* sentinel */ },
515 };
516 MODULE_DEVICE_TABLE(of, miic_of_mtable);
517 
518 static struct platform_driver miic_driver = {
519 	.driver = {
520 		.name	 = "rzn1_miic",
521 		.suppress_bind_attrs = true,
522 		.of_match_table = miic_of_mtable,
523 	},
524 	.probe = miic_probe,
525 	.remove = miic_remove,
526 };
527 module_platform_driver(miic_driver);
528 
529 MODULE_LICENSE("GPL");
530 MODULE_DESCRIPTION("Renesas MII converter PCS driver");
531 MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
532