1 /*
2  * Broadcom GENET MDIO routines
3  *
4  * Copyright (c) 2014 Broadcom Corporation
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 
12 #include <linux/types.h>
13 #include <linux/delay.h>
14 #include <linux/wait.h>
15 #include <linux/mii.h>
16 #include <linux/ethtool.h>
17 #include <linux/bitops.h>
18 #include <linux/netdevice.h>
19 #include <linux/platform_device.h>
20 #include <linux/phy.h>
21 #include <linux/phy_fixed.h>
22 #include <linux/brcmphy.h>
23 #include <linux/of.h>
24 #include <linux/of_net.h>
25 #include <linux/of_mdio.h>
26 #include <linux/platform_data/bcmgenet.h>
27 
28 #include "bcmgenet.h"
29 
30 /* read a value from the MII */
31 static int bcmgenet_mii_read(struct mii_bus *bus, int phy_id, int location)
32 {
33 	int ret;
34 	struct net_device *dev = bus->priv;
35 	struct bcmgenet_priv *priv = netdev_priv(dev);
36 	u32 reg;
37 
38 	bcmgenet_umac_writel(priv, (MDIO_RD | (phy_id << MDIO_PMD_SHIFT) |
39 			     (location << MDIO_REG_SHIFT)), UMAC_MDIO_CMD);
40 	/* Start MDIO transaction*/
41 	reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
42 	reg |= MDIO_START_BUSY;
43 	bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
44 	wait_event_timeout(priv->wq,
45 			   !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
46 			   & MDIO_START_BUSY),
47 			   HZ / 100);
48 	ret = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
49 
50 	if (ret & MDIO_READ_FAIL)
51 		return -EIO;
52 
53 	return ret & 0xffff;
54 }
55 
56 /* write a value to the MII */
57 static int bcmgenet_mii_write(struct mii_bus *bus, int phy_id,
58 			      int location, u16 val)
59 {
60 	struct net_device *dev = bus->priv;
61 	struct bcmgenet_priv *priv = netdev_priv(dev);
62 	u32 reg;
63 
64 	bcmgenet_umac_writel(priv, (MDIO_WR | (phy_id << MDIO_PMD_SHIFT) |
65 			     (location << MDIO_REG_SHIFT) | (0xffff & val)),
66 			     UMAC_MDIO_CMD);
67 	reg = bcmgenet_umac_readl(priv, UMAC_MDIO_CMD);
68 	reg |= MDIO_START_BUSY;
69 	bcmgenet_umac_writel(priv, reg, UMAC_MDIO_CMD);
70 	wait_event_timeout(priv->wq,
71 			   !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD) &
72 			   MDIO_START_BUSY),
73 			   HZ / 100);
74 
75 	return 0;
76 }
77 
78 /* setup netdev link state when PHY link status change and
79  * update UMAC and RGMII block when link up
80  */
81 void bcmgenet_mii_setup(struct net_device *dev)
82 {
83 	struct bcmgenet_priv *priv = netdev_priv(dev);
84 	struct phy_device *phydev = priv->phydev;
85 	u32 reg, cmd_bits = 0;
86 	bool status_changed = false;
87 
88 	if (priv->old_link != phydev->link) {
89 		status_changed = true;
90 		priv->old_link = phydev->link;
91 	}
92 
93 	if (phydev->link) {
94 		/* check speed/duplex/pause changes */
95 		if (priv->old_speed != phydev->speed) {
96 			status_changed = true;
97 			priv->old_speed = phydev->speed;
98 		}
99 
100 		if (priv->old_duplex != phydev->duplex) {
101 			status_changed = true;
102 			priv->old_duplex = phydev->duplex;
103 		}
104 
105 		if (priv->old_pause != phydev->pause) {
106 			status_changed = true;
107 			priv->old_pause = phydev->pause;
108 		}
109 
110 		/* done if nothing has changed */
111 		if (!status_changed)
112 			return;
113 
114 		/* speed */
115 		if (phydev->speed == SPEED_1000)
116 			cmd_bits = UMAC_SPEED_1000;
117 		else if (phydev->speed == SPEED_100)
118 			cmd_bits = UMAC_SPEED_100;
119 		else
120 			cmd_bits = UMAC_SPEED_10;
121 		cmd_bits <<= CMD_SPEED_SHIFT;
122 
123 		/* duplex */
124 		if (phydev->duplex != DUPLEX_FULL)
125 			cmd_bits |= CMD_HD_EN;
126 
127 		/* pause capability */
128 		if (!phydev->pause)
129 			cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE;
130 
131 		/*
132 		 * Program UMAC and RGMII block based on established
133 		 * link speed, duplex, and pause. The speed set in
134 		 * umac->cmd tell RGMII block which clock to use for
135 		 * transmit -- 25MHz(100Mbps) or 125MHz(1Gbps).
136 		 * Receive clock is provided by the PHY.
137 		 */
138 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
139 		reg &= ~OOB_DISABLE;
140 		reg |= RGMII_LINK;
141 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
142 
143 		reg = bcmgenet_umac_readl(priv, UMAC_CMD);
144 		reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
145 			       CMD_HD_EN |
146 			       CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE);
147 		reg |= cmd_bits;
148 		bcmgenet_umac_writel(priv, reg, UMAC_CMD);
149 	} else {
150 		/* done if nothing has changed */
151 		if (!status_changed)
152 			return;
153 
154 		/* needed for MoCA fixed PHY to reflect correct link status */
155 		netif_carrier_off(dev);
156 	}
157 
158 	phy_print_status(phydev);
159 }
160 
161 void bcmgenet_mii_reset(struct net_device *dev)
162 {
163 	struct bcmgenet_priv *priv = netdev_priv(dev);
164 
165 	if (priv->phydev) {
166 		phy_init_hw(priv->phydev);
167 		phy_start_aneg(priv->phydev);
168 	}
169 }
170 
171 void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
172 {
173 	struct bcmgenet_priv *priv = netdev_priv(dev);
174 	u32 reg = 0;
175 
176 	/* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
177 	if (!GENET_IS_V4(priv))
178 		return;
179 
180 	reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
181 	if (enable) {
182 		reg &= ~EXT_CK25_DIS;
183 		bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
184 		mdelay(1);
185 
186 		reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
187 		reg |= EXT_GPHY_RESET;
188 		bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
189 		mdelay(1);
190 
191 		reg &= ~EXT_GPHY_RESET;
192 	} else {
193 		reg |= EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN | EXT_GPHY_RESET;
194 		bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
195 		mdelay(1);
196 		reg |= EXT_CK25_DIS;
197 	}
198 	bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
199 	udelay(60);
200 }
201 
202 static void bcmgenet_internal_phy_setup(struct net_device *dev)
203 {
204 	struct bcmgenet_priv *priv = netdev_priv(dev);
205 	u32 reg;
206 
207 	/* Power up PHY */
208 	bcmgenet_phy_power_set(dev, true);
209 	/* enable APD */
210 	reg = bcmgenet_ext_readl(priv, EXT_EXT_PWR_MGMT);
211 	reg |= EXT_PWR_DN_EN_LD;
212 	bcmgenet_ext_writel(priv, reg, EXT_EXT_PWR_MGMT);
213 	bcmgenet_mii_reset(dev);
214 }
215 
216 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
217 {
218 	u32 reg;
219 
220 	/* Speed settings are set in bcmgenet_mii_setup() */
221 	reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
222 	reg |= LED_ACT_SOURCE_MAC;
223 	bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
224 }
225 
226 int bcmgenet_mii_config(struct net_device *dev, bool init)
227 {
228 	struct bcmgenet_priv *priv = netdev_priv(dev);
229 	struct phy_device *phydev = priv->phydev;
230 	struct device *kdev = &priv->pdev->dev;
231 	const char *phy_name = NULL;
232 	u32 id_mode_dis = 0;
233 	u32 port_ctrl;
234 	u32 reg;
235 
236 	priv->ext_phy = !phy_is_internal(priv->phydev) &&
237 			(priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
238 
239 	if (phy_is_internal(priv->phydev))
240 		priv->phy_interface = PHY_INTERFACE_MODE_NA;
241 
242 	switch (priv->phy_interface) {
243 	case PHY_INTERFACE_MODE_NA:
244 	case PHY_INTERFACE_MODE_MOCA:
245 		/* Irrespective of the actually configured PHY speed (100 or
246 		 * 1000) GENETv4 only has an internal GPHY so we will just end
247 		 * up masking the Gigabit features from what we support, not
248 		 * switching to the EPHY
249 		 */
250 		if (GENET_IS_V4(priv))
251 			port_ctrl = PORT_MODE_INT_GPHY;
252 		else
253 			port_ctrl = PORT_MODE_INT_EPHY;
254 
255 		bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
256 
257 		if (phy_is_internal(priv->phydev)) {
258 			phy_name = "internal PHY";
259 			bcmgenet_internal_phy_setup(dev);
260 		} else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
261 			phy_name = "MoCA";
262 			bcmgenet_moca_phy_setup(priv);
263 		}
264 		break;
265 
266 	case PHY_INTERFACE_MODE_MII:
267 		phy_name = "external MII";
268 		phydev->supported &= PHY_BASIC_FEATURES;
269 		bcmgenet_sys_writel(priv,
270 				    PORT_MODE_EXT_EPHY, SYS_PORT_CTRL);
271 		break;
272 
273 	case PHY_INTERFACE_MODE_REVMII:
274 		phy_name = "external RvMII";
275 		/* of_mdiobus_register took care of reading the 'max-speed'
276 		 * PHY property for us, effectively limiting the PHY supported
277 		 * capabilities, use that knowledge to also configure the
278 		 * Reverse MII interface correctly.
279 		 */
280 		if ((priv->phydev->supported & PHY_BASIC_FEATURES) ==
281 				PHY_BASIC_FEATURES)
282 			port_ctrl = PORT_MODE_EXT_RVMII_25;
283 		else
284 			port_ctrl = PORT_MODE_EXT_RVMII_50;
285 		bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
286 		break;
287 
288 	case PHY_INTERFACE_MODE_RGMII:
289 		/* RGMII_NO_ID: TXC transitions at the same time as TXD
290 		 *		(requires PCB or receiver-side delay)
291 		 * RGMII:	Add 2ns delay on TXC (90 degree shift)
292 		 *
293 		 * ID is implicitly disabled for 100Mbps (RG)MII operation.
294 		 */
295 		id_mode_dis = BIT(16);
296 		/* fall through */
297 	case PHY_INTERFACE_MODE_RGMII_TXID:
298 		if (id_mode_dis)
299 			phy_name = "external RGMII (no delay)";
300 		else
301 			phy_name = "external RGMII (TX delay)";
302 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
303 		reg |= RGMII_MODE_EN | id_mode_dis;
304 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
305 		bcmgenet_sys_writel(priv,
306 				    PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
307 		break;
308 	default:
309 		dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
310 		return -EINVAL;
311 	}
312 
313 	if (init)
314 		dev_info(kdev, "configuring instance for %s\n", phy_name);
315 
316 	return 0;
317 }
318 
319 static int bcmgenet_mii_probe(struct net_device *dev)
320 {
321 	struct bcmgenet_priv *priv = netdev_priv(dev);
322 	struct device_node *dn = priv->pdev->dev.of_node;
323 	struct phy_device *phydev;
324 	u32 phy_flags;
325 	int ret;
326 
327 	/* Communicate the integrated PHY revision */
328 	phy_flags = priv->gphy_rev;
329 
330 	/* Initialize link state variables that bcmgenet_mii_setup() uses */
331 	priv->old_link = -1;
332 	priv->old_speed = -1;
333 	priv->old_duplex = -1;
334 	priv->old_pause = -1;
335 
336 	if (dn) {
337 		if (priv->phydev) {
338 			pr_info("PHY already attached\n");
339 			return 0;
340 		}
341 
342 		/* In the case of a fixed PHY, the DT node associated
343 		 * to the PHY is the Ethernet MAC DT node.
344 		 */
345 		if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
346 			ret = of_phy_register_fixed_link(dn);
347 			if (ret)
348 				return ret;
349 
350 			priv->phy_dn = of_node_get(dn);
351 		}
352 
353 		phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
354 					phy_flags, priv->phy_interface);
355 		if (!phydev) {
356 			pr_err("could not attach to PHY\n");
357 			return -ENODEV;
358 		}
359 	} else {
360 		phydev = priv->phydev;
361 		phydev->dev_flags = phy_flags;
362 
363 		ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
364 					 priv->phy_interface);
365 		if (ret) {
366 			pr_err("could not attach to PHY\n");
367 			return -ENODEV;
368 		}
369 	}
370 
371 	priv->phydev = phydev;
372 
373 	/* Configure port multiplexer based on what the probed PHY device since
374 	 * reading the 'max-speed' property determines the maximum supported
375 	 * PHY speed which is needed for bcmgenet_mii_config() to configure
376 	 * things appropriately.
377 	 */
378 	ret = bcmgenet_mii_config(dev, true);
379 	if (ret) {
380 		phy_disconnect(priv->phydev);
381 		return ret;
382 	}
383 
384 	phydev->advertising = phydev->supported;
385 
386 	/* The internal PHY has its link interrupts routed to the
387 	 * Ethernet MAC ISRs
388 	 */
389 	if (phy_is_internal(priv->phydev))
390 		priv->mii_bus->irq[phydev->addr] = PHY_IGNORE_INTERRUPT;
391 	else
392 		priv->mii_bus->irq[phydev->addr] = PHY_POLL;
393 
394 	pr_info("attached PHY at address %d [%s]\n",
395 		phydev->addr, phydev->drv->name);
396 
397 	return 0;
398 }
399 
400 static int bcmgenet_mii_alloc(struct bcmgenet_priv *priv)
401 {
402 	struct mii_bus *bus;
403 
404 	if (priv->mii_bus)
405 		return 0;
406 
407 	priv->mii_bus = mdiobus_alloc();
408 	if (!priv->mii_bus) {
409 		pr_err("failed to allocate\n");
410 		return -ENOMEM;
411 	}
412 
413 	bus = priv->mii_bus;
414 	bus->priv = priv->dev;
415 	bus->name = "bcmgenet MII bus";
416 	bus->parent = &priv->pdev->dev;
417 	bus->read = bcmgenet_mii_read;
418 	bus->write = bcmgenet_mii_write;
419 	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d",
420 		 priv->pdev->name, priv->pdev->id);
421 
422 	bus->irq = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL);
423 	if (!bus->irq) {
424 		mdiobus_free(priv->mii_bus);
425 		return -ENOMEM;
426 	}
427 
428 	return 0;
429 }
430 
431 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
432 {
433 	struct device_node *dn = priv->pdev->dev.of_node;
434 	struct device *kdev = &priv->pdev->dev;
435 	struct device_node *mdio_dn;
436 	char *compat;
437 	int ret;
438 
439 	compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
440 	if (!compat)
441 		return -ENOMEM;
442 
443 	mdio_dn = of_find_compatible_node(dn, NULL, compat);
444 	kfree(compat);
445 	if (!mdio_dn) {
446 		dev_err(kdev, "unable to find MDIO bus node\n");
447 		return -ENODEV;
448 	}
449 
450 	ret = of_mdiobus_register(priv->mii_bus, mdio_dn);
451 	if (ret) {
452 		dev_err(kdev, "failed to register MDIO bus\n");
453 		return ret;
454 	}
455 
456 	/* Fetch the PHY phandle */
457 	priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
458 
459 	/* Get the link mode */
460 	priv->phy_interface = of_get_phy_mode(dn);
461 
462 	return 0;
463 }
464 
465 static int bcmgenet_fixed_phy_link_update(struct net_device *dev,
466 					  struct fixed_phy_status *status)
467 {
468 	if (dev && dev->phydev && status)
469 		status->link = dev->phydev->link;
470 
471 	return 0;
472 }
473 
474 static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)
475 {
476 	struct device *kdev = &priv->pdev->dev;
477 	struct bcmgenet_platform_data *pd = kdev->platform_data;
478 	struct mii_bus *mdio = priv->mii_bus;
479 	struct phy_device *phydev;
480 	int ret;
481 
482 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
483 		/*
484 		 * Internal or external PHY with MDIO access
485 		 */
486 		if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
487 			mdio->phy_mask = ~(1 << pd->phy_address);
488 		else
489 			mdio->phy_mask = 0;
490 
491 		ret = mdiobus_register(mdio);
492 		if (ret) {
493 			dev_err(kdev, "failed to register MDIO bus\n");
494 			return ret;
495 		}
496 
497 		if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
498 			phydev = mdio->phy_map[pd->phy_address];
499 		else
500 			phydev = phy_find_first(mdio);
501 
502 		if (!phydev) {
503 			dev_err(kdev, "failed to register PHY device\n");
504 			mdiobus_unregister(mdio);
505 			return -ENODEV;
506 		}
507 	} else {
508 		/*
509 		 * MoCA port or no MDIO access.
510 		 * Use fixed PHY to represent the link layer.
511 		 */
512 		struct fixed_phy_status fphy_status = {
513 			.link = 1,
514 			.speed = pd->phy_speed,
515 			.duplex = pd->phy_duplex,
516 			.pause = 0,
517 			.asym_pause = 0,
518 		};
519 
520 		phydev = fixed_phy_register(PHY_POLL, &fphy_status, NULL);
521 		if (!phydev || IS_ERR(phydev)) {
522 			dev_err(kdev, "failed to register fixed PHY device\n");
523 			return -ENODEV;
524 		}
525 
526 		if (priv->hw_params->flags & GENET_HAS_MOCA_LINK_DET) {
527 			ret = fixed_phy_set_link_update(
528 				phydev, bcmgenet_fixed_phy_link_update);
529 			if (!ret)
530 				phydev->link = 0;
531 		}
532 	}
533 
534 	priv->phydev = phydev;
535 	priv->phy_interface = pd->phy_interface;
536 
537 	return 0;
538 }
539 
540 static int bcmgenet_mii_bus_init(struct bcmgenet_priv *priv)
541 {
542 	struct device_node *dn = priv->pdev->dev.of_node;
543 
544 	if (dn)
545 		return bcmgenet_mii_of_init(priv);
546 	else
547 		return bcmgenet_mii_pd_init(priv);
548 }
549 
550 int bcmgenet_mii_init(struct net_device *dev)
551 {
552 	struct bcmgenet_priv *priv = netdev_priv(dev);
553 	int ret;
554 
555 	ret = bcmgenet_mii_alloc(priv);
556 	if (ret)
557 		return ret;
558 
559 	ret = bcmgenet_mii_bus_init(priv);
560 	if (ret)
561 		goto out_free;
562 
563 	ret = bcmgenet_mii_probe(dev);
564 	if (ret)
565 		goto out;
566 
567 	return 0;
568 
569 out:
570 	of_node_put(priv->phy_dn);
571 	mdiobus_unregister(priv->mii_bus);
572 out_free:
573 	kfree(priv->mii_bus->irq);
574 	mdiobus_free(priv->mii_bus);
575 	return ret;
576 }
577 
578 void bcmgenet_mii_exit(struct net_device *dev)
579 {
580 	struct bcmgenet_priv *priv = netdev_priv(dev);
581 
582 	of_node_put(priv->phy_dn);
583 	mdiobus_unregister(priv->mii_bus);
584 	kfree(priv->mii_bus->irq);
585 	mdiobus_free(priv->mii_bus);
586 }
587