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 = dev->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 	struct bcmgenet_priv *priv;
119 	u32 reg;
120 
121 	if (dev && dev->phydev && status) {
122 		priv = netdev_priv(dev);
123 		reg = bcmgenet_umac_readl(priv, UMAC_MODE);
124 		status->link = !!(reg & MODE_LINK_STATUS);
125 	}
126 
127 	return 0;
128 }
129 
130 void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
131 {
132 	struct bcmgenet_priv *priv = netdev_priv(dev);
133 	u32 reg = 0;
134 
135 	/* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
136 	if (GENET_IS_V4(priv)) {
137 		reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
138 		if (enable) {
139 			reg &= ~EXT_CK25_DIS;
140 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
141 			mdelay(1);
142 
143 			reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
144 			reg |= EXT_GPHY_RESET;
145 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
146 			mdelay(1);
147 
148 			reg &= ~EXT_GPHY_RESET;
149 		} else {
150 			reg |= EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN |
151 			       EXT_GPHY_RESET;
152 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
153 			mdelay(1);
154 			reg |= EXT_CK25_DIS;
155 		}
156 		bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
157 		udelay(60);
158 	} else {
159 		mdelay(1);
160 	}
161 }
162 
163 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
164 {
165 	u32 reg;
166 
167 	if (!GENET_IS_V5(priv)) {
168 		/* Speed settings are set in bcmgenet_mii_setup() */
169 		reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
170 		reg |= LED_ACT_SOURCE_MAC;
171 		bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
172 	}
173 
174 	if (priv->hw_params->flags & GENET_HAS_MOCA_LINK_DET)
175 		fixed_phy_set_link_update(priv->dev->phydev,
176 					  bcmgenet_fixed_phy_link_update);
177 }
178 
179 int bcmgenet_mii_config(struct net_device *dev, bool init)
180 {
181 	struct bcmgenet_priv *priv = netdev_priv(dev);
182 	struct phy_device *phydev = dev->phydev;
183 	struct device *kdev = &priv->pdev->dev;
184 	const char *phy_name = NULL;
185 	u32 id_mode_dis = 0;
186 	u32 port_ctrl;
187 	u32 reg;
188 
189 	priv->ext_phy = !priv->internal_phy &&
190 			(priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
191 
192 	switch (priv->phy_interface) {
193 	case PHY_INTERFACE_MODE_INTERNAL:
194 	case PHY_INTERFACE_MODE_MOCA:
195 		/* Irrespective of the actually configured PHY speed (100 or
196 		 * 1000) GENETv4 only has an internal GPHY so we will just end
197 		 * up masking the Gigabit features from what we support, not
198 		 * switching to the EPHY
199 		 */
200 		if (GENET_IS_V4(priv))
201 			port_ctrl = PORT_MODE_INT_GPHY;
202 		else
203 			port_ctrl = PORT_MODE_INT_EPHY;
204 
205 		bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
206 
207 		if (priv->internal_phy) {
208 			phy_name = "internal PHY";
209 		} else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
210 			phy_name = "MoCA";
211 			bcmgenet_moca_phy_setup(priv);
212 		}
213 		break;
214 
215 	case PHY_INTERFACE_MODE_MII:
216 		phy_name = "external MII";
217 		phy_set_max_speed(phydev, SPEED_100);
218 		bcmgenet_sys_writel(priv,
219 				    PORT_MODE_EXT_EPHY, SYS_PORT_CTRL);
220 		break;
221 
222 	case PHY_INTERFACE_MODE_REVMII:
223 		phy_name = "external RvMII";
224 		/* of_mdiobus_register took care of reading the 'max-speed'
225 		 * PHY property for us, effectively limiting the PHY supported
226 		 * capabilities, use that knowledge to also configure the
227 		 * Reverse MII interface correctly.
228 		 */
229 		if (linkmode_test_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
230 				      dev->phydev->supported))
231 			port_ctrl = PORT_MODE_EXT_RVMII_50;
232 		else
233 			port_ctrl = PORT_MODE_EXT_RVMII_25;
234 		bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
235 		break;
236 
237 	case PHY_INTERFACE_MODE_RGMII:
238 		/* RGMII_NO_ID: TXC transitions at the same time as TXD
239 		 *		(requires PCB or receiver-side delay)
240 		 * RGMII:	Add 2ns delay on TXC (90 degree shift)
241 		 *
242 		 * ID is implicitly disabled for 100Mbps (RG)MII operation.
243 		 */
244 		id_mode_dis = BIT(16);
245 		/* fall through */
246 	case PHY_INTERFACE_MODE_RGMII_TXID:
247 		if (id_mode_dis)
248 			phy_name = "external RGMII (no delay)";
249 		else
250 			phy_name = "external RGMII (TX delay)";
251 		bcmgenet_sys_writel(priv,
252 				    PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
253 		break;
254 	default:
255 		dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
256 		return -EINVAL;
257 	}
258 
259 	/* This is an external PHY (xMII), so we need to enable the RGMII
260 	 * block for the interface to work
261 	 */
262 	if (priv->ext_phy) {
263 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
264 		reg |= RGMII_MODE_EN | id_mode_dis;
265 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
266 	}
267 
268 	if (init)
269 		dev_info(kdev, "configuring instance for %s\n", phy_name);
270 
271 	return 0;
272 }
273 
274 int bcmgenet_mii_probe(struct net_device *dev)
275 {
276 	struct bcmgenet_priv *priv = netdev_priv(dev);
277 	struct device_node *dn = priv->pdev->dev.of_node;
278 	struct phy_device *phydev;
279 	u32 phy_flags;
280 	int ret;
281 
282 	/* Communicate the integrated PHY revision */
283 	phy_flags = priv->gphy_rev;
284 
285 	/* Initialize link state variables that bcmgenet_mii_setup() uses */
286 	priv->old_link = -1;
287 	priv->old_speed = -1;
288 	priv->old_duplex = -1;
289 	priv->old_pause = -1;
290 
291 	if (dn) {
292 		phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
293 					phy_flags, priv->phy_interface);
294 		if (!phydev) {
295 			pr_err("could not attach to PHY\n");
296 			return -ENODEV;
297 		}
298 	} else {
299 		phydev = dev->phydev;
300 		phydev->dev_flags = phy_flags;
301 
302 		ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
303 					 priv->phy_interface);
304 		if (ret) {
305 			pr_err("could not attach to PHY\n");
306 			return -ENODEV;
307 		}
308 	}
309 
310 	/* Configure port multiplexer based on what the probed PHY device since
311 	 * reading the 'max-speed' property determines the maximum supported
312 	 * PHY speed which is needed for bcmgenet_mii_config() to configure
313 	 * things appropriately.
314 	 */
315 	ret = bcmgenet_mii_config(dev, true);
316 	if (ret) {
317 		phy_disconnect(dev->phydev);
318 		return ret;
319 	}
320 
321 	linkmode_copy(phydev->advertising, phydev->supported);
322 
323 	/* The internal PHY has its link interrupts routed to the
324 	 * Ethernet MAC ISRs. On GENETv5 there is a hardware issue
325 	 * that prevents the signaling of link UP interrupts when
326 	 * the link operates at 10Mbps, so fallback to polling for
327 	 * those versions of GENET.
328 	 */
329 	if (priv->internal_phy && !GENET_IS_V5(priv))
330 		dev->phydev->irq = PHY_IGNORE_INTERRUPT;
331 
332 	return 0;
333 }
334 
335 static struct device_node *bcmgenet_mii_of_find_mdio(struct bcmgenet_priv *priv)
336 {
337 	struct device_node *dn = priv->pdev->dev.of_node;
338 	struct device *kdev = &priv->pdev->dev;
339 	char *compat;
340 
341 	compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
342 	if (!compat)
343 		return NULL;
344 
345 	priv->mdio_dn = of_get_compatible_child(dn, compat);
346 	kfree(compat);
347 	if (!priv->mdio_dn) {
348 		dev_err(kdev, "unable to find MDIO bus node\n");
349 		return NULL;
350 	}
351 
352 	return priv->mdio_dn;
353 }
354 
355 static void bcmgenet_mii_pdata_init(struct bcmgenet_priv *priv,
356 				    struct unimac_mdio_pdata *ppd)
357 {
358 	struct device *kdev = &priv->pdev->dev;
359 	struct bcmgenet_platform_data *pd = kdev->platform_data;
360 
361 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
362 		/*
363 		 * Internal or external PHY with MDIO access
364 		 */
365 		if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
366 			ppd->phy_mask = 1 << pd->phy_address;
367 		else
368 			ppd->phy_mask = 0;
369 	}
370 }
371 
372 static int bcmgenet_mii_wait(void *wait_func_data)
373 {
374 	struct bcmgenet_priv *priv = wait_func_data;
375 
376 	wait_event_timeout(priv->wq,
377 			   !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
378 			   & MDIO_START_BUSY),
379 			   HZ / 100);
380 	return 0;
381 }
382 
383 static int bcmgenet_mii_register(struct bcmgenet_priv *priv)
384 {
385 	struct platform_device *pdev = priv->pdev;
386 	struct bcmgenet_platform_data *pdata = pdev->dev.platform_data;
387 	struct device_node *dn = pdev->dev.of_node;
388 	struct unimac_mdio_pdata ppd;
389 	struct platform_device *ppdev;
390 	struct resource *pres, res;
391 	int id, ret;
392 
393 	pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
394 	memset(&res, 0, sizeof(res));
395 	memset(&ppd, 0, sizeof(ppd));
396 
397 	ppd.wait_func = bcmgenet_mii_wait;
398 	ppd.wait_func_data = priv;
399 	ppd.bus_name = "bcmgenet MII bus";
400 
401 	/* Unimac MDIO bus controller starts at UniMAC offset + MDIO_CMD
402 	 * and is 2 * 32-bits word long, 8 bytes total.
403 	 */
404 	res.start = pres->start + GENET_UMAC_OFF + UMAC_MDIO_CMD;
405 	res.end = res.start + 8;
406 	res.flags = IORESOURCE_MEM;
407 
408 	if (dn)
409 		id = of_alias_get_id(dn, "eth");
410 	else
411 		id = pdev->id;
412 
413 	ppdev = platform_device_alloc(UNIMAC_MDIO_DRV_NAME, id);
414 	if (!ppdev)
415 		return -ENOMEM;
416 
417 	/* Retain this platform_device pointer for later cleanup */
418 	priv->mii_pdev = ppdev;
419 	ppdev->dev.parent = &pdev->dev;
420 	ppdev->dev.of_node = bcmgenet_mii_of_find_mdio(priv);
421 	if (pdata)
422 		bcmgenet_mii_pdata_init(priv, &ppd);
423 
424 	ret = platform_device_add_resources(ppdev, &res, 1);
425 	if (ret)
426 		goto out;
427 
428 	ret = platform_device_add_data(ppdev, &ppd, sizeof(ppd));
429 	if (ret)
430 		goto out;
431 
432 	ret = platform_device_add(ppdev);
433 	if (ret)
434 		goto out;
435 
436 	return 0;
437 out:
438 	platform_device_put(ppdev);
439 	return ret;
440 }
441 
442 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
443 {
444 	struct device_node *dn = priv->pdev->dev.of_node;
445 	struct device *kdev = &priv->pdev->dev;
446 	struct phy_device *phydev;
447 	int phy_mode;
448 	int ret;
449 
450 	/* Fetch the PHY phandle */
451 	priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
452 
453 	/* In the case of a fixed PHY, the DT node associated
454 	 * to the PHY is the Ethernet MAC DT node.
455 	 */
456 	if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
457 		ret = of_phy_register_fixed_link(dn);
458 		if (ret)
459 			return ret;
460 
461 		priv->phy_dn = of_node_get(dn);
462 	}
463 
464 	/* Get the link mode */
465 	phy_mode = of_get_phy_mode(dn);
466 	if (phy_mode < 0) {
467 		dev_err(kdev, "invalid PHY mode property\n");
468 		return phy_mode;
469 	}
470 
471 	priv->phy_interface = phy_mode;
472 
473 	/* We need to specifically look up whether this PHY interface is internal
474 	 * or not *before* we even try to probe the PHY driver over MDIO as we
475 	 * may have shut down the internal PHY for power saving purposes.
476 	 */
477 	if (priv->phy_interface == PHY_INTERFACE_MODE_INTERNAL)
478 		priv->internal_phy = true;
479 
480 	/* Make sure we initialize MoCA PHYs with a link down */
481 	if (phy_mode == PHY_INTERFACE_MODE_MOCA) {
482 		phydev = of_phy_find_device(dn);
483 		if (phydev) {
484 			phydev->link = 0;
485 			put_device(&phydev->mdio.dev);
486 		}
487 	}
488 
489 	return 0;
490 }
491 
492 static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)
493 {
494 	struct device *kdev = &priv->pdev->dev;
495 	struct bcmgenet_platform_data *pd = kdev->platform_data;
496 	char phy_name[MII_BUS_ID_SIZE + 3];
497 	char mdio_bus_id[MII_BUS_ID_SIZE];
498 	struct phy_device *phydev;
499 
500 	snprintf(mdio_bus_id, MII_BUS_ID_SIZE, "%s-%d",
501 		 UNIMAC_MDIO_DRV_NAME, priv->pdev->id);
502 
503 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
504 		snprintf(phy_name, MII_BUS_ID_SIZE, PHY_ID_FMT,
505 			 mdio_bus_id, pd->phy_address);
506 
507 		/*
508 		 * Internal or external PHY with MDIO access
509 		 */
510 		phydev = phy_attach(priv->dev, phy_name, pd->phy_interface);
511 		if (!phydev) {
512 			dev_err(kdev, "failed to register PHY device\n");
513 			return -ENODEV;
514 		}
515 	} else {
516 		/*
517 		 * MoCA port or no MDIO access.
518 		 * Use fixed PHY to represent the link layer.
519 		 */
520 		struct fixed_phy_status fphy_status = {
521 			.link = 1,
522 			.speed = pd->phy_speed,
523 			.duplex = pd->phy_duplex,
524 			.pause = 0,
525 			.asym_pause = 0,
526 		};
527 
528 		phydev = fixed_phy_register(PHY_POLL, &fphy_status, -1, NULL);
529 		if (!phydev || IS_ERR(phydev)) {
530 			dev_err(kdev, "failed to register fixed PHY device\n");
531 			return -ENODEV;
532 		}
533 
534 		/* Make sure we initialize MoCA PHYs with a link down */
535 		phydev->link = 0;
536 
537 	}
538 
539 	priv->phy_interface = pd->phy_interface;
540 
541 	return 0;
542 }
543 
544 static int bcmgenet_mii_bus_init(struct bcmgenet_priv *priv)
545 {
546 	struct device_node *dn = priv->pdev->dev.of_node;
547 
548 	if (dn)
549 		return bcmgenet_mii_of_init(priv);
550 	else
551 		return bcmgenet_mii_pd_init(priv);
552 }
553 
554 int bcmgenet_mii_init(struct net_device *dev)
555 {
556 	struct bcmgenet_priv *priv = netdev_priv(dev);
557 	int ret;
558 
559 	ret = bcmgenet_mii_register(priv);
560 	if (ret)
561 		return ret;
562 
563 	ret = bcmgenet_mii_bus_init(priv);
564 	if (ret)
565 		goto out;
566 
567 	return 0;
568 
569 out:
570 	bcmgenet_mii_exit(dev);
571 	return ret;
572 }
573 
574 void bcmgenet_mii_exit(struct net_device *dev)
575 {
576 	struct bcmgenet_priv *priv = netdev_priv(dev);
577 	struct device_node *dn = priv->pdev->dev.of_node;
578 
579 	if (of_phy_is_fixed_link(dn))
580 		of_phy_deregister_fixed_link(dn);
581 	of_node_put(priv->phy_dn);
582 	platform_device_unregister(priv->mii_pdev);
583 }
584