xref: /openbmc/linux/drivers/net/pcs/pcs-rzn1-miic.c (revision ac3cb6de)
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 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 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 const struct phylink_pcs_ops miic_phylink_ops = {
283 	.pcs_validate = miic_validate,
284 	.pcs_config = miic_config,
285 	.pcs_link_up = miic_link_up,
286 };
287 
288 struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
289 {
290 	struct platform_device *pdev;
291 	struct miic_port *miic_port;
292 	struct device_node *pcs_np;
293 	struct miic *miic;
294 	u32 port;
295 
296 	if (!of_device_is_available(np))
297 		return ERR_PTR(-ENODEV);
298 
299 	if (of_property_read_u32(np, "reg", &port))
300 		return ERR_PTR(-EINVAL);
301 
302 	if (port > MIIC_MAX_NR_PORTS || port < 1)
303 		return ERR_PTR(-EINVAL);
304 
305 	/* The PCS pdev is attached to the parent node */
306 	pcs_np = of_get_parent(np);
307 	if (!pcs_np)
308 		return ERR_PTR(-ENODEV);
309 
310 	if (!of_device_is_available(pcs_np)) {
311 		of_node_put(pcs_np);
312 		return ERR_PTR(-ENODEV);
313 	}
314 
315 	pdev = of_find_device_by_node(pcs_np);
316 	of_node_put(pcs_np);
317 	if (!pdev || !platform_get_drvdata(pdev))
318 		return ERR_PTR(-EPROBE_DEFER);
319 
320 	miic_port = kzalloc(sizeof(*miic_port), GFP_KERNEL);
321 	if (!miic_port)
322 		return ERR_PTR(-ENOMEM);
323 
324 	miic = platform_get_drvdata(pdev);
325 	device_link_add(dev, miic->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
326 
327 	miic_port->miic = miic;
328 	miic_port->port = port - 1;
329 	miic_port->pcs.ops = &miic_phylink_ops;
330 
331 	return &miic_port->pcs;
332 }
333 EXPORT_SYMBOL(miic_create);
334 
335 void miic_destroy(struct phylink_pcs *pcs)
336 {
337 	struct miic_port *miic_port = phylink_pcs_to_miic_port(pcs);
338 
339 	miic_converter_enable(miic_port->miic, miic_port->port, 0);
340 	kfree(miic_port);
341 }
342 EXPORT_SYMBOL(miic_destroy);
343 
344 static int miic_init_hw(struct miic *miic, u32 cfg_mode)
345 {
346 	int port;
347 
348 	/* Unlock write access to accessory registers (cf datasheet). If this
349 	 * is going to be used in conjunction with the Cortex-M3, this sequence
350 	 * will have to be moved in register write
351 	 */
352 	miic_reg_writel(miic, MIIC_PRCMD, 0x00A5);
353 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
354 	miic_reg_writel(miic, MIIC_PRCMD, 0xFFFE);
355 	miic_reg_writel(miic, MIIC_PRCMD, 0x0001);
356 
357 	miic_reg_writel(miic, MIIC_MODCTRL,
358 			FIELD_PREP(MIIC_MODCTRL_SW_MODE, cfg_mode));
359 
360 	for (port = 0; port < MIIC_MAX_NR_PORTS; port++) {
361 		miic_converter_enable(miic, port, 0);
362 		/* Disable speed/duplex control from these registers, datasheet
363 		 * says switch registers should be used to setup switch port
364 		 * speed and duplex.
365 		 */
366 		miic_reg_writel(miic, MIIC_SWCTRL, 0x0);
367 		miic_reg_writel(miic, MIIC_SWDUPC, 0x0);
368 	}
369 
370 	return 0;
371 }
372 
373 static bool miic_modctrl_match(s8 table_val[MIIC_MODCTRL_CONF_CONV_NUM],
374 			       s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM])
375 {
376 	int i;
377 
378 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
379 		if (dt_val[i] == MIIC_MODCTRL_CONF_NONE)
380 			continue;
381 
382 		if (dt_val[i] != table_val[i])
383 			return false;
384 	}
385 
386 	return true;
387 }
388 
389 static void miic_dump_conf(struct device *dev,
390 			   s8 conf[MIIC_MODCTRL_CONF_CONV_NUM])
391 {
392 	const char *conf_name;
393 	int i;
394 
395 	for (i = 0; i < MIIC_MODCTRL_CONF_CONV_NUM; i++) {
396 		if (conf[i] != MIIC_MODCTRL_CONF_NONE)
397 			conf_name = conf_to_string[conf[i]];
398 		else
399 			conf_name = "NONE";
400 
401 		dev_err(dev, "%s: %s\n", index_to_string[i], conf_name);
402 	}
403 }
404 
405 static int miic_match_dt_conf(struct device *dev,
406 			      s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM],
407 			      u32 *mode_cfg)
408 {
409 	struct modctrl_match *table_entry;
410 	int i;
411 
412 	for (i = 0; i < ARRAY_SIZE(modctrl_match_table); i++) {
413 		table_entry = &modctrl_match_table[i];
414 
415 		if (miic_modctrl_match(table_entry->conv, dt_val)) {
416 			*mode_cfg = table_entry->mode_cfg;
417 			return 0;
418 		}
419 	}
420 
421 	dev_err(dev, "Failed to apply requested configuration\n");
422 	miic_dump_conf(dev, dt_val);
423 
424 	return -EINVAL;
425 }
426 
427 static int miic_parse_dt(struct device *dev, u32 *mode_cfg)
428 {
429 	s8 dt_val[MIIC_MODCTRL_CONF_CONV_NUM];
430 	struct device_node *np = dev->of_node;
431 	struct device_node *conv;
432 	u32 conf;
433 	int port;
434 
435 	memset(dt_val, MIIC_MODCTRL_CONF_NONE, sizeof(dt_val));
436 
437 	if (of_property_read_u32(np, "renesas,miic-switch-portin", &conf) == 0)
438 		dt_val[0] = conf;
439 
440 	for_each_child_of_node(np, conv) {
441 		if (of_property_read_u32(conv, "reg", &port))
442 			continue;
443 
444 		if (!of_device_is_available(conv))
445 			continue;
446 
447 		if (of_property_read_u32(conv, "renesas,miic-input", &conf) == 0)
448 			dt_val[port] = conf;
449 	}
450 
451 	return miic_match_dt_conf(dev, dt_val, mode_cfg);
452 }
453 
454 static int miic_probe(struct platform_device *pdev)
455 {
456 	struct device *dev = &pdev->dev;
457 	struct miic *miic;
458 	u32 mode_cfg;
459 	int ret;
460 
461 	ret = miic_parse_dt(dev, &mode_cfg);
462 	if (ret < 0)
463 		return ret;
464 
465 	miic = devm_kzalloc(dev, sizeof(*miic), GFP_KERNEL);
466 	if (!miic)
467 		return -ENOMEM;
468 
469 	spin_lock_init(&miic->lock);
470 	miic->dev = dev;
471 	miic->base = devm_platform_ioremap_resource(pdev, 0);
472 	if (IS_ERR(miic->base))
473 		return PTR_ERR(miic->base);
474 
475 	ret = devm_pm_runtime_enable(dev);
476 	if (ret < 0)
477 		return ret;
478 
479 	ret = pm_runtime_resume_and_get(dev);
480 	if (ret < 0)
481 		return ret;
482 
483 	ret = miic_init_hw(miic, mode_cfg);
484 	if (ret)
485 		goto disable_runtime_pm;
486 
487 	/* miic_create() relies on that fact that data are attached to the
488 	 * platform device to determine if the driver is ready so this needs to
489 	 * be the last thing to be done after everything is initialized
490 	 * properly.
491 	 */
492 	platform_set_drvdata(pdev, miic);
493 
494 	return 0;
495 
496 disable_runtime_pm:
497 	pm_runtime_put(dev);
498 
499 	return ret;
500 }
501 
502 static int miic_remove(struct platform_device *pdev)
503 {
504 	pm_runtime_put(&pdev->dev);
505 
506 	return 0;
507 }
508 
509 static const struct of_device_id miic_of_mtable[] = {
510 	{ .compatible = "renesas,rzn1-miic" },
511 	{ /* sentinel */ },
512 };
513 MODULE_DEVICE_TABLE(of, miic_of_mtable);
514 
515 static struct platform_driver miic_driver = {
516 	.driver = {
517 		.name	 = "rzn1_miic",
518 		.suppress_bind_attrs = true,
519 		.of_match_table = miic_of_mtable,
520 	},
521 	.probe = miic_probe,
522 	.remove = miic_remove,
523 };
524 module_platform_driver(miic_driver);
525 
526 MODULE_LICENSE("GPL");
527 MODULE_DESCRIPTION("Renesas MII converter PCS driver");
528 MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
529