1 /*
2  * Broadcom GENET MDIO routines
3  *
4  * Copyright (c) 2014-2017 Broadcom
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 #include <linux/platform_data/mdio-bcm-unimac.h>
28 
29 #include "bcmgenet.h"
30 
31 /* setup netdev link state when PHY link status change and
32  * update UMAC and RGMII block when link up
33  */
34 void bcmgenet_mii_setup(struct net_device *dev)
35 {
36 	struct bcmgenet_priv *priv = netdev_priv(dev);
37 	struct phy_device *phydev = priv->phydev;
38 	u32 reg, cmd_bits = 0;
39 	bool status_changed = false;
40 
41 	if (priv->old_link != phydev->link) {
42 		status_changed = true;
43 		priv->old_link = phydev->link;
44 	}
45 
46 	if (phydev->link) {
47 		/* check speed/duplex/pause changes */
48 		if (priv->old_speed != phydev->speed) {
49 			status_changed = true;
50 			priv->old_speed = phydev->speed;
51 		}
52 
53 		if (priv->old_duplex != phydev->duplex) {
54 			status_changed = true;
55 			priv->old_duplex = phydev->duplex;
56 		}
57 
58 		if (priv->old_pause != phydev->pause) {
59 			status_changed = true;
60 			priv->old_pause = phydev->pause;
61 		}
62 
63 		/* done if nothing has changed */
64 		if (!status_changed)
65 			return;
66 
67 		/* speed */
68 		if (phydev->speed == SPEED_1000)
69 			cmd_bits = UMAC_SPEED_1000;
70 		else if (phydev->speed == SPEED_100)
71 			cmd_bits = UMAC_SPEED_100;
72 		else
73 			cmd_bits = UMAC_SPEED_10;
74 		cmd_bits <<= CMD_SPEED_SHIFT;
75 
76 		/* duplex */
77 		if (phydev->duplex != DUPLEX_FULL)
78 			cmd_bits |= CMD_HD_EN;
79 
80 		/* pause capability */
81 		if (!phydev->pause)
82 			cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE;
83 
84 		/*
85 		 * Program UMAC and RGMII block based on established
86 		 * link speed, duplex, and pause. The speed set in
87 		 * umac->cmd tell RGMII block which clock to use for
88 		 * transmit -- 25MHz(100Mbps) or 125MHz(1Gbps).
89 		 * Receive clock is provided by the PHY.
90 		 */
91 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
92 		reg &= ~OOB_DISABLE;
93 		reg |= RGMII_LINK;
94 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
95 
96 		reg = bcmgenet_umac_readl(priv, UMAC_CMD);
97 		reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
98 			       CMD_HD_EN |
99 			       CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE);
100 		reg |= cmd_bits;
101 		bcmgenet_umac_writel(priv, reg, UMAC_CMD);
102 	} else {
103 		/* done if nothing has changed */
104 		if (!status_changed)
105 			return;
106 
107 		/* needed for MoCA fixed PHY to reflect correct link status */
108 		netif_carrier_off(dev);
109 	}
110 
111 	phy_print_status(phydev);
112 }
113 
114 
115 static int bcmgenet_fixed_phy_link_update(struct net_device *dev,
116 					  struct fixed_phy_status *status)
117 {
118 	if (dev && dev->phydev && status)
119 		status->link = dev->phydev->link;
120 
121 	return 0;
122 }
123 
124 /* Perform a voluntary PHY software reset, since the EPHY is very finicky about
125  * not doing it and will start corrupting packets
126  */
127 void bcmgenet_mii_reset(struct net_device *dev)
128 {
129 	struct bcmgenet_priv *priv = netdev_priv(dev);
130 
131 	if (GENET_IS_V4(priv))
132 		return;
133 
134 	if (priv->phydev) {
135 		phy_init_hw(priv->phydev);
136 		phy_start_aneg(priv->phydev);
137 	}
138 }
139 
140 void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
141 {
142 	struct bcmgenet_priv *priv = netdev_priv(dev);
143 	u32 reg = 0;
144 
145 	/* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
146 	if (GENET_IS_V4(priv)) {
147 		reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
148 		if (enable) {
149 			reg &= ~EXT_CK25_DIS;
150 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
151 			mdelay(1);
152 
153 			reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
154 			reg |= EXT_GPHY_RESET;
155 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
156 			mdelay(1);
157 
158 			reg &= ~EXT_GPHY_RESET;
159 		} else {
160 			reg |= EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN |
161 			       EXT_GPHY_RESET;
162 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
163 			mdelay(1);
164 			reg |= EXT_CK25_DIS;
165 		}
166 		bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
167 		udelay(60);
168 	} else {
169 		mdelay(1);
170 	}
171 }
172 
173 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
174 {
175 	u32 reg;
176 
177 	if (!GENET_IS_V5(priv)) {
178 		/* Speed settings are set in bcmgenet_mii_setup() */
179 		reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
180 		reg |= LED_ACT_SOURCE_MAC;
181 		bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
182 	}
183 
184 	if (priv->hw_params->flags & GENET_HAS_MOCA_LINK_DET)
185 		fixed_phy_set_link_update(priv->phydev,
186 					  bcmgenet_fixed_phy_link_update);
187 }
188 
189 int bcmgenet_mii_config(struct net_device *dev, bool init)
190 {
191 	struct bcmgenet_priv *priv = netdev_priv(dev);
192 	struct phy_device *phydev = priv->phydev;
193 	struct device *kdev = &priv->pdev->dev;
194 	const char *phy_name = NULL;
195 	u32 id_mode_dis = 0;
196 	u32 port_ctrl;
197 	u32 reg;
198 
199 	priv->ext_phy = !priv->internal_phy &&
200 			(priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
201 
202 	switch (priv->phy_interface) {
203 	case PHY_INTERFACE_MODE_INTERNAL:
204 	case PHY_INTERFACE_MODE_MOCA:
205 		/* Irrespective of the actually configured PHY speed (100 or
206 		 * 1000) GENETv4 only has an internal GPHY so we will just end
207 		 * up masking the Gigabit features from what we support, not
208 		 * switching to the EPHY
209 		 */
210 		if (GENET_IS_V4(priv))
211 			port_ctrl = PORT_MODE_INT_GPHY;
212 		else
213 			port_ctrl = PORT_MODE_INT_EPHY;
214 
215 		bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
216 
217 		if (priv->internal_phy) {
218 			phy_name = "internal PHY";
219 		} else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
220 			phy_name = "MoCA";
221 			bcmgenet_moca_phy_setup(priv);
222 		}
223 		break;
224 
225 	case PHY_INTERFACE_MODE_MII:
226 		phy_name = "external MII";
227 		phydev->supported &= PHY_BASIC_FEATURES;
228 		bcmgenet_sys_writel(priv,
229 				    PORT_MODE_EXT_EPHY, SYS_PORT_CTRL);
230 		break;
231 
232 	case PHY_INTERFACE_MODE_REVMII:
233 		phy_name = "external RvMII";
234 		/* of_mdiobus_register took care of reading the 'max-speed'
235 		 * PHY property for us, effectively limiting the PHY supported
236 		 * capabilities, use that knowledge to also configure the
237 		 * Reverse MII interface correctly.
238 		 */
239 		if ((priv->phydev->supported & PHY_BASIC_FEATURES) ==
240 				PHY_BASIC_FEATURES)
241 			port_ctrl = PORT_MODE_EXT_RVMII_25;
242 		else
243 			port_ctrl = PORT_MODE_EXT_RVMII_50;
244 		bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
245 		break;
246 
247 	case PHY_INTERFACE_MODE_RGMII:
248 		/* RGMII_NO_ID: TXC transitions at the same time as TXD
249 		 *		(requires PCB or receiver-side delay)
250 		 * RGMII:	Add 2ns delay on TXC (90 degree shift)
251 		 *
252 		 * ID is implicitly disabled for 100Mbps (RG)MII operation.
253 		 */
254 		id_mode_dis = BIT(16);
255 		/* fall through */
256 	case PHY_INTERFACE_MODE_RGMII_TXID:
257 		if (id_mode_dis)
258 			phy_name = "external RGMII (no delay)";
259 		else
260 			phy_name = "external RGMII (TX delay)";
261 		bcmgenet_sys_writel(priv,
262 				    PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
263 		break;
264 	default:
265 		dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
266 		return -EINVAL;
267 	}
268 
269 	/* This is an external PHY (xMII), so we need to enable the RGMII
270 	 * block for the interface to work
271 	 */
272 	if (priv->ext_phy) {
273 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
274 		reg |= RGMII_MODE_EN | id_mode_dis;
275 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
276 	}
277 
278 	if (init)
279 		dev_info(kdev, "configuring instance for %s\n", phy_name);
280 
281 	return 0;
282 }
283 
284 int bcmgenet_mii_probe(struct net_device *dev)
285 {
286 	struct bcmgenet_priv *priv = netdev_priv(dev);
287 	struct device_node *dn = priv->pdev->dev.of_node;
288 	struct phy_device *phydev;
289 	u32 phy_flags;
290 	int ret;
291 
292 	/* Communicate the integrated PHY revision */
293 	phy_flags = priv->gphy_rev;
294 
295 	/* Initialize link state variables that bcmgenet_mii_setup() uses */
296 	priv->old_link = -1;
297 	priv->old_speed = -1;
298 	priv->old_duplex = -1;
299 	priv->old_pause = -1;
300 
301 	if (dn) {
302 		phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
303 					phy_flags, priv->phy_interface);
304 		if (!phydev) {
305 			pr_err("could not attach to PHY\n");
306 			return -ENODEV;
307 		}
308 	} else {
309 		phydev = priv->phydev;
310 		phydev->dev_flags = phy_flags;
311 
312 		ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
313 					 priv->phy_interface);
314 		if (ret) {
315 			pr_err("could not attach to PHY\n");
316 			return -ENODEV;
317 		}
318 	}
319 
320 	priv->phydev = phydev;
321 
322 	/* Configure port multiplexer based on what the probed PHY device since
323 	 * reading the 'max-speed' property determines the maximum supported
324 	 * PHY speed which is needed for bcmgenet_mii_config() to configure
325 	 * things appropriately.
326 	 */
327 	ret = bcmgenet_mii_config(dev, true);
328 	if (ret) {
329 		phy_disconnect(priv->phydev);
330 		return ret;
331 	}
332 
333 	phydev->advertising = phydev->supported;
334 
335 	/* The internal PHY has its link interrupts routed to the
336 	 * Ethernet MAC ISRs
337 	 */
338 	if (priv->internal_phy)
339 		priv->phydev->irq = PHY_IGNORE_INTERRUPT;
340 
341 	return 0;
342 }
343 
344 static struct device_node *bcmgenet_mii_of_find_mdio(struct bcmgenet_priv *priv)
345 {
346 	struct device_node *dn = priv->pdev->dev.of_node;
347 	struct device *kdev = &priv->pdev->dev;
348 	char *compat;
349 
350 	compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
351 	if (!compat)
352 		return NULL;
353 
354 	priv->mdio_dn = of_find_compatible_node(dn, NULL, compat);
355 	kfree(compat);
356 	if (!priv->mdio_dn) {
357 		dev_err(kdev, "unable to find MDIO bus node\n");
358 		return NULL;
359 	}
360 
361 	return priv->mdio_dn;
362 }
363 
364 static void bcmgenet_mii_pdata_init(struct bcmgenet_priv *priv,
365 				    struct unimac_mdio_pdata *ppd)
366 {
367 	struct device *kdev = &priv->pdev->dev;
368 	struct bcmgenet_platform_data *pd = kdev->platform_data;
369 
370 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
371 		/*
372 		 * Internal or external PHY with MDIO access
373 		 */
374 		if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
375 			ppd->phy_mask = 1 << pd->phy_address;
376 		else
377 			ppd->phy_mask = 0;
378 	}
379 }
380 
381 static int bcmgenet_mii_wait(void *wait_func_data)
382 {
383 	struct bcmgenet_priv *priv = wait_func_data;
384 
385 	wait_event_timeout(priv->wq,
386 			   !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
387 			   & MDIO_START_BUSY),
388 			   HZ / 100);
389 	return 0;
390 }
391 
392 static int bcmgenet_mii_register(struct bcmgenet_priv *priv)
393 {
394 	struct platform_device *pdev = priv->pdev;
395 	struct bcmgenet_platform_data *pdata = pdev->dev.platform_data;
396 	struct device_node *dn = pdev->dev.of_node;
397 	struct unimac_mdio_pdata ppd;
398 	struct platform_device *ppdev;
399 	struct resource *pres, res;
400 	int id, ret;
401 
402 	pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
403 	memset(&res, 0, sizeof(res));
404 	memset(&ppd, 0, sizeof(ppd));
405 
406 	ppd.wait_func = bcmgenet_mii_wait;
407 	ppd.wait_func_data = priv;
408 	ppd.bus_name = "bcmgenet MII bus";
409 
410 	/* Unimac MDIO bus controller starts at UniMAC offset + MDIO_CMD
411 	 * and is 2 * 32-bits word long, 8 bytes total.
412 	 */
413 	res.start = pres->start + GENET_UMAC_OFF + UMAC_MDIO_CMD;
414 	res.end = res.start + 8;
415 	res.flags = IORESOURCE_MEM;
416 
417 	if (dn)
418 		id = of_alias_get_id(dn, "eth");
419 	else
420 		id = pdev->id;
421 
422 	ppdev = platform_device_alloc(UNIMAC_MDIO_DRV_NAME, id);
423 	if (!ppdev)
424 		return -ENOMEM;
425 
426 	/* Retain this platform_device pointer for later cleanup */
427 	priv->mii_pdev = ppdev;
428 	ppdev->dev.parent = &pdev->dev;
429 	ppdev->dev.of_node = bcmgenet_mii_of_find_mdio(priv);
430 	if (pdata)
431 		bcmgenet_mii_pdata_init(priv, &ppd);
432 
433 	ret = platform_device_add_resources(ppdev, &res, 1);
434 	if (ret)
435 		goto out;
436 
437 	ret = platform_device_add_data(ppdev, &ppd, sizeof(ppd));
438 	if (ret)
439 		goto out;
440 
441 	ret = platform_device_add(ppdev);
442 	if (ret)
443 		goto out;
444 
445 	return 0;
446 out:
447 	platform_device_put(ppdev);
448 	return ret;
449 }
450 
451 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
452 {
453 	struct device_node *dn = priv->pdev->dev.of_node;
454 	struct device *kdev = &priv->pdev->dev;
455 	struct phy_device *phydev;
456 	int phy_mode;
457 	int ret;
458 
459 	/* Fetch the PHY phandle */
460 	priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
461 
462 	/* In the case of a fixed PHY, the DT node associated
463 	 * to the PHY is the Ethernet MAC DT node.
464 	 */
465 	if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
466 		ret = of_phy_register_fixed_link(dn);
467 		if (ret)
468 			return ret;
469 
470 		priv->phy_dn = of_node_get(dn);
471 	}
472 
473 	/* Get the link mode */
474 	phy_mode = of_get_phy_mode(dn);
475 	if (phy_mode < 0) {
476 		dev_err(kdev, "invalid PHY mode property\n");
477 		return phy_mode;
478 	}
479 
480 	priv->phy_interface = phy_mode;
481 
482 	/* We need to specifically look up whether this PHY interface is internal
483 	 * or not *before* we even try to probe the PHY driver over MDIO as we
484 	 * may have shut down the internal PHY for power saving purposes.
485 	 */
486 	if (priv->phy_interface == PHY_INTERFACE_MODE_INTERNAL)
487 		priv->internal_phy = true;
488 
489 	/* Make sure we initialize MoCA PHYs with a link down */
490 	if (phy_mode == PHY_INTERFACE_MODE_MOCA) {
491 		phydev = of_phy_find_device(dn);
492 		if (phydev) {
493 			phydev->link = 0;
494 			put_device(&phydev->mdio.dev);
495 		}
496 	}
497 
498 	return 0;
499 }
500 
501 static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)
502 {
503 	struct device *kdev = &priv->pdev->dev;
504 	struct bcmgenet_platform_data *pd = kdev->platform_data;
505 	char phy_name[MII_BUS_ID_SIZE + 3];
506 	char mdio_bus_id[MII_BUS_ID_SIZE];
507 	struct phy_device *phydev;
508 
509 	snprintf(mdio_bus_id, MII_BUS_ID_SIZE, "%s-%d",
510 		 UNIMAC_MDIO_DRV_NAME, priv->pdev->id);
511 
512 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
513 		snprintf(phy_name, MII_BUS_ID_SIZE, PHY_ID_FMT,
514 			 mdio_bus_id, pd->phy_address);
515 
516 		/*
517 		 * Internal or external PHY with MDIO access
518 		 */
519 		phydev = phy_attach(priv->dev, phy_name, pd->phy_interface);
520 		if (!phydev) {
521 			dev_err(kdev, "failed to register PHY device\n");
522 			return -ENODEV;
523 		}
524 	} else {
525 		/*
526 		 * MoCA port or no MDIO access.
527 		 * Use fixed PHY to represent the link layer.
528 		 */
529 		struct fixed_phy_status fphy_status = {
530 			.link = 1,
531 			.speed = pd->phy_speed,
532 			.duplex = pd->phy_duplex,
533 			.pause = 0,
534 			.asym_pause = 0,
535 		};
536 
537 		phydev = fixed_phy_register(PHY_POLL, &fphy_status, -1, NULL);
538 		if (!phydev || IS_ERR(phydev)) {
539 			dev_err(kdev, "failed to register fixed PHY device\n");
540 			return -ENODEV;
541 		}
542 
543 		/* Make sure we initialize MoCA PHYs with a link down */
544 		phydev->link = 0;
545 
546 	}
547 
548 	priv->phydev = phydev;
549 	priv->phy_interface = pd->phy_interface;
550 
551 	return 0;
552 }
553 
554 static int bcmgenet_mii_bus_init(struct bcmgenet_priv *priv)
555 {
556 	struct device_node *dn = priv->pdev->dev.of_node;
557 
558 	if (dn)
559 		return bcmgenet_mii_of_init(priv);
560 	else
561 		return bcmgenet_mii_pd_init(priv);
562 }
563 
564 int bcmgenet_mii_init(struct net_device *dev)
565 {
566 	struct bcmgenet_priv *priv = netdev_priv(dev);
567 	int ret;
568 
569 	ret = bcmgenet_mii_register(priv);
570 	if (ret)
571 		return ret;
572 
573 	ret = bcmgenet_mii_bus_init(priv);
574 	if (ret)
575 		goto out;
576 
577 	return 0;
578 
579 out:
580 	bcmgenet_mii_exit(dev);
581 	return ret;
582 }
583 
584 void bcmgenet_mii_exit(struct net_device *dev)
585 {
586 	struct bcmgenet_priv *priv = netdev_priv(dev);
587 	struct device_node *dn = priv->pdev->dev.of_node;
588 
589 	if (of_phy_is_fixed_link(dn))
590 		of_phy_deregister_fixed_link(dn);
591 	of_node_put(priv->phy_dn);
592 	platform_device_unregister(priv->mii_pdev);
593 	platform_device_put(priv->mii_pdev);
594 }
595