1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Broadcom GENET MDIO routines
4  *
5  * Copyright (c) 2014-2017 Broadcom
6  */
7 
8 
9 #include <linux/types.h>
10 #include <linux/delay.h>
11 #include <linux/wait.h>
12 #include <linux/mii.h>
13 #include <linux/ethtool.h>
14 #include <linux/bitops.h>
15 #include <linux/netdevice.h>
16 #include <linux/platform_device.h>
17 #include <linux/phy.h>
18 #include <linux/phy_fixed.h>
19 #include <linux/brcmphy.h>
20 #include <linux/of.h>
21 #include <linux/of_net.h>
22 #include <linux/of_mdio.h>
23 #include <linux/platform_data/bcmgenet.h>
24 #include <linux/platform_data/mdio-bcm-unimac.h>
25 
26 #include "bcmgenet.h"
27 
28 /* setup netdev link state when PHY link status change and
29  * update UMAC and RGMII block when link up
30  */
31 void bcmgenet_mii_setup(struct net_device *dev)
32 {
33 	struct bcmgenet_priv *priv = netdev_priv(dev);
34 	struct phy_device *phydev = dev->phydev;
35 	u32 reg, cmd_bits = 0;
36 	bool status_changed = false;
37 
38 	if (priv->old_link != phydev->link) {
39 		status_changed = true;
40 		priv->old_link = phydev->link;
41 	}
42 
43 	if (phydev->link) {
44 		/* check speed/duplex/pause changes */
45 		if (priv->old_speed != phydev->speed) {
46 			status_changed = true;
47 			priv->old_speed = phydev->speed;
48 		}
49 
50 		if (priv->old_duplex != phydev->duplex) {
51 			status_changed = true;
52 			priv->old_duplex = phydev->duplex;
53 		}
54 
55 		if (priv->old_pause != phydev->pause) {
56 			status_changed = true;
57 			priv->old_pause = phydev->pause;
58 		}
59 
60 		/* done if nothing has changed */
61 		if (!status_changed)
62 			return;
63 
64 		/* speed */
65 		if (phydev->speed == SPEED_1000)
66 			cmd_bits = UMAC_SPEED_1000;
67 		else if (phydev->speed == SPEED_100)
68 			cmd_bits = UMAC_SPEED_100;
69 		else
70 			cmd_bits = UMAC_SPEED_10;
71 		cmd_bits <<= CMD_SPEED_SHIFT;
72 
73 		/* duplex */
74 		if (phydev->duplex != DUPLEX_FULL)
75 			cmd_bits |= CMD_HD_EN;
76 
77 		/* pause capability */
78 		if (!phydev->pause)
79 			cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE;
80 
81 		/*
82 		 * Program UMAC and RGMII block based on established
83 		 * link speed, duplex, and pause. The speed set in
84 		 * umac->cmd tell RGMII block which clock to use for
85 		 * transmit -- 25MHz(100Mbps) or 125MHz(1Gbps).
86 		 * Receive clock is provided by the PHY.
87 		 */
88 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
89 		reg &= ~OOB_DISABLE;
90 		reg |= RGMII_LINK;
91 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
92 
93 		reg = bcmgenet_umac_readl(priv, UMAC_CMD);
94 		reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) |
95 			       CMD_HD_EN |
96 			       CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE);
97 		reg |= cmd_bits;
98 		bcmgenet_umac_writel(priv, reg, UMAC_CMD);
99 	} else {
100 		/* done if nothing has changed */
101 		if (!status_changed)
102 			return;
103 
104 		/* needed for MoCA fixed PHY to reflect correct link status */
105 		netif_carrier_off(dev);
106 	}
107 
108 	phy_print_status(phydev);
109 }
110 
111 
112 static int bcmgenet_fixed_phy_link_update(struct net_device *dev,
113 					  struct fixed_phy_status *status)
114 {
115 	struct bcmgenet_priv *priv;
116 	u32 reg;
117 
118 	if (dev && dev->phydev && status) {
119 		priv = netdev_priv(dev);
120 		reg = bcmgenet_umac_readl(priv, UMAC_MODE);
121 		status->link = !!(reg & MODE_LINK_STATUS);
122 	}
123 
124 	return 0;
125 }
126 
127 void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
128 {
129 	struct bcmgenet_priv *priv = netdev_priv(dev);
130 	u32 reg = 0;
131 
132 	/* EXT_GPHY_CTRL is only valid for GENETv4 and onward */
133 	if (GENET_IS_V4(priv)) {
134 		reg = bcmgenet_ext_readl(priv, EXT_GPHY_CTRL);
135 		if (enable) {
136 			reg &= ~EXT_CK25_DIS;
137 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
138 			mdelay(1);
139 
140 			reg &= ~(EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN);
141 			reg |= EXT_GPHY_RESET;
142 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
143 			mdelay(1);
144 
145 			reg &= ~EXT_GPHY_RESET;
146 		} else {
147 			reg |= EXT_CFG_IDDQ_BIAS | EXT_CFG_PWR_DOWN |
148 			       EXT_GPHY_RESET;
149 			bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
150 			mdelay(1);
151 			reg |= EXT_CK25_DIS;
152 		}
153 		bcmgenet_ext_writel(priv, reg, EXT_GPHY_CTRL);
154 		udelay(60);
155 	} else {
156 		mdelay(1);
157 	}
158 }
159 
160 static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
161 {
162 	u32 reg;
163 
164 	if (!GENET_IS_V5(priv)) {
165 		/* Speed settings are set in bcmgenet_mii_setup() */
166 		reg = bcmgenet_sys_readl(priv, SYS_PORT_CTRL);
167 		reg |= LED_ACT_SOURCE_MAC;
168 		bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);
169 	}
170 
171 	if (priv->hw_params->flags & GENET_HAS_MOCA_LINK_DET)
172 		fixed_phy_set_link_update(priv->dev->phydev,
173 					  bcmgenet_fixed_phy_link_update);
174 }
175 
176 int bcmgenet_mii_config(struct net_device *dev, bool init)
177 {
178 	struct bcmgenet_priv *priv = netdev_priv(dev);
179 	struct phy_device *phydev = dev->phydev;
180 	struct device *kdev = &priv->pdev->dev;
181 	const char *phy_name = NULL;
182 	u32 id_mode_dis = 0;
183 	u32 port_ctrl;
184 	int bmcr = -1;
185 	int ret;
186 	u32 reg;
187 
188 	/* MAC clocking workaround during reset of umac state machines */
189 	reg = bcmgenet_umac_readl(priv, UMAC_CMD);
190 	if (reg & CMD_SW_RESET) {
191 		/* An MII PHY must be isolated to prevent TXC contention */
192 		if (priv->phy_interface == PHY_INTERFACE_MODE_MII) {
193 			ret = phy_read(phydev, MII_BMCR);
194 			if (ret >= 0) {
195 				bmcr = ret;
196 				ret = phy_write(phydev, MII_BMCR,
197 						bmcr | BMCR_ISOLATE);
198 			}
199 			if (ret) {
200 				netdev_err(dev, "failed to isolate PHY\n");
201 				return ret;
202 			}
203 		}
204 		/* Switch MAC clocking to RGMII generated clock */
205 		bcmgenet_sys_writel(priv, PORT_MODE_EXT_GPHY, SYS_PORT_CTRL);
206 		/* Ensure 5 clks with Rx disabled
207 		 * followed by 5 clks with Reset asserted
208 		 */
209 		udelay(4);
210 		reg &= ~(CMD_SW_RESET | CMD_LCL_LOOP_EN);
211 		bcmgenet_umac_writel(priv, reg, UMAC_CMD);
212 		/* Ensure 5 more clocks before Rx is enabled */
213 		udelay(2);
214 	}
215 
216 	switch (priv->phy_interface) {
217 	case PHY_INTERFACE_MODE_INTERNAL:
218 		phy_name = "internal PHY";
219 		/* fall through */
220 	case PHY_INTERFACE_MODE_MOCA:
221 		/* Irrespective of the actually configured PHY speed (100 or
222 		 * 1000) GENETv4 only has an internal GPHY so we will just end
223 		 * up masking the Gigabit features from what we support, not
224 		 * switching to the EPHY
225 		 */
226 		if (GENET_IS_V4(priv))
227 			port_ctrl = PORT_MODE_INT_GPHY;
228 		else
229 			port_ctrl = PORT_MODE_INT_EPHY;
230 
231 		if (!phy_name) {
232 			phy_name = "MoCA";
233 			bcmgenet_moca_phy_setup(priv);
234 		}
235 		break;
236 
237 	case PHY_INTERFACE_MODE_MII:
238 		phy_name = "external MII";
239 		phy_set_max_speed(phydev, SPEED_100);
240 		port_ctrl = PORT_MODE_EXT_EPHY;
241 		break;
242 
243 	case PHY_INTERFACE_MODE_REVMII:
244 		phy_name = "external RvMII";
245 		/* of_mdiobus_register took care of reading the 'max-speed'
246 		 * PHY property for us, effectively limiting the PHY supported
247 		 * capabilities, use that knowledge to also configure the
248 		 * Reverse MII interface correctly.
249 		 */
250 		if (linkmode_test_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
251 				      dev->phydev->supported))
252 			port_ctrl = PORT_MODE_EXT_RVMII_50;
253 		else
254 			port_ctrl = PORT_MODE_EXT_RVMII_25;
255 		break;
256 
257 	case PHY_INTERFACE_MODE_RGMII:
258 		/* RGMII_NO_ID: TXC transitions at the same time as TXD
259 		 *		(requires PCB or receiver-side delay)
260 		 *
261 		 * ID is implicitly disabled for 100Mbps (RG)MII operation.
262 		 */
263 		phy_name = "external RGMII (no delay)";
264 		id_mode_dis = BIT(16);
265 		port_ctrl = PORT_MODE_EXT_GPHY;
266 		break;
267 
268 	case PHY_INTERFACE_MODE_RGMII_TXID:
269 		/* RGMII_TXID:	Add 2ns delay on TXC (90 degree shift) */
270 		phy_name = "external RGMII (TX delay)";
271 		port_ctrl = PORT_MODE_EXT_GPHY;
272 		break;
273 
274 	case PHY_INTERFACE_MODE_RGMII_RXID:
275 		phy_name = "external RGMII (RX delay)";
276 		port_ctrl = PORT_MODE_EXT_GPHY;
277 		break;
278 	default:
279 		dev_err(kdev, "unknown phy mode: %d\n", priv->phy_interface);
280 		return -EINVAL;
281 	}
282 
283 	bcmgenet_sys_writel(priv, port_ctrl, SYS_PORT_CTRL);
284 
285 	/* Restore the MII PHY after isolation */
286 	if (bmcr >= 0)
287 		phy_write(phydev, MII_BMCR, bmcr);
288 
289 	priv->ext_phy = !priv->internal_phy &&
290 			(priv->phy_interface != PHY_INTERFACE_MODE_MOCA);
291 
292 	/* This is an external PHY (xMII), so we need to enable the RGMII
293 	 * block for the interface to work
294 	 */
295 	if (priv->ext_phy) {
296 		reg = bcmgenet_ext_readl(priv, EXT_RGMII_OOB_CTRL);
297 		reg |= id_mode_dis;
298 		if (GENET_IS_V1(priv) || GENET_IS_V2(priv) || GENET_IS_V3(priv))
299 			reg |= RGMII_MODE_EN_V123;
300 		else
301 			reg |= RGMII_MODE_EN;
302 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
303 	}
304 
305 	if (init)
306 		dev_info(kdev, "configuring instance for %s\n", phy_name);
307 
308 	return 0;
309 }
310 
311 int bcmgenet_mii_probe(struct net_device *dev)
312 {
313 	struct bcmgenet_priv *priv = netdev_priv(dev);
314 	struct device_node *dn = priv->pdev->dev.of_node;
315 	struct phy_device *phydev;
316 	u32 phy_flags = 0;
317 	int ret;
318 
319 	/* Communicate the integrated PHY revision */
320 	if (priv->internal_phy)
321 		phy_flags = priv->gphy_rev;
322 
323 	/* Initialize link state variables that bcmgenet_mii_setup() uses */
324 	priv->old_link = -1;
325 	priv->old_speed = -1;
326 	priv->old_duplex = -1;
327 	priv->old_pause = -1;
328 
329 	if (dn) {
330 		phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
331 					phy_flags, priv->phy_interface);
332 		if (!phydev) {
333 			pr_err("could not attach to PHY\n");
334 			return -ENODEV;
335 		}
336 	} else {
337 		phydev = dev->phydev;
338 		phydev->dev_flags = phy_flags;
339 
340 		ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
341 					 priv->phy_interface);
342 		if (ret) {
343 			pr_err("could not attach to PHY\n");
344 			return -ENODEV;
345 		}
346 	}
347 
348 	/* Configure port multiplexer based on what the probed PHY device since
349 	 * reading the 'max-speed' property determines the maximum supported
350 	 * PHY speed which is needed for bcmgenet_mii_config() to configure
351 	 * things appropriately.
352 	 */
353 	ret = bcmgenet_mii_config(dev, true);
354 	if (ret) {
355 		phy_disconnect(dev->phydev);
356 		return ret;
357 	}
358 
359 	linkmode_copy(phydev->advertising, phydev->supported);
360 
361 	/* The internal PHY has its link interrupts routed to the
362 	 * Ethernet MAC ISRs. On GENETv5 there is a hardware issue
363 	 * that prevents the signaling of link UP interrupts when
364 	 * the link operates at 10Mbps, so fallback to polling for
365 	 * those versions of GENET.
366 	 */
367 	if (priv->internal_phy && !GENET_IS_V5(priv))
368 		dev->phydev->irq = PHY_IGNORE_INTERRUPT;
369 
370 	return 0;
371 }
372 
373 static struct device_node *bcmgenet_mii_of_find_mdio(struct bcmgenet_priv *priv)
374 {
375 	struct device_node *dn = priv->pdev->dev.of_node;
376 	struct device *kdev = &priv->pdev->dev;
377 	char *compat;
378 
379 	compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
380 	if (!compat)
381 		return NULL;
382 
383 	priv->mdio_dn = of_get_compatible_child(dn, compat);
384 	kfree(compat);
385 	if (!priv->mdio_dn) {
386 		dev_err(kdev, "unable to find MDIO bus node\n");
387 		return NULL;
388 	}
389 
390 	return priv->mdio_dn;
391 }
392 
393 static void bcmgenet_mii_pdata_init(struct bcmgenet_priv *priv,
394 				    struct unimac_mdio_pdata *ppd)
395 {
396 	struct device *kdev = &priv->pdev->dev;
397 	struct bcmgenet_platform_data *pd = kdev->platform_data;
398 
399 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
400 		/*
401 		 * Internal or external PHY with MDIO access
402 		 */
403 		if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
404 			ppd->phy_mask = 1 << pd->phy_address;
405 		else
406 			ppd->phy_mask = 0;
407 	}
408 }
409 
410 static int bcmgenet_mii_wait(void *wait_func_data)
411 {
412 	struct bcmgenet_priv *priv = wait_func_data;
413 
414 	wait_event_timeout(priv->wq,
415 			   !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
416 			   & MDIO_START_BUSY),
417 			   HZ / 100);
418 	return 0;
419 }
420 
421 static int bcmgenet_mii_register(struct bcmgenet_priv *priv)
422 {
423 	struct platform_device *pdev = priv->pdev;
424 	struct bcmgenet_platform_data *pdata = pdev->dev.platform_data;
425 	struct device_node *dn = pdev->dev.of_node;
426 	struct unimac_mdio_pdata ppd;
427 	struct platform_device *ppdev;
428 	struct resource *pres, res;
429 	int id, ret;
430 
431 	pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
432 	memset(&res, 0, sizeof(res));
433 	memset(&ppd, 0, sizeof(ppd));
434 
435 	ppd.wait_func = bcmgenet_mii_wait;
436 	ppd.wait_func_data = priv;
437 	ppd.bus_name = "bcmgenet MII bus";
438 
439 	/* Unimac MDIO bus controller starts at UniMAC offset + MDIO_CMD
440 	 * and is 2 * 32-bits word long, 8 bytes total.
441 	 */
442 	res.start = pres->start + GENET_UMAC_OFF + UMAC_MDIO_CMD;
443 	res.end = res.start + 8;
444 	res.flags = IORESOURCE_MEM;
445 
446 	if (dn)
447 		id = of_alias_get_id(dn, "eth");
448 	else
449 		id = pdev->id;
450 
451 	ppdev = platform_device_alloc(UNIMAC_MDIO_DRV_NAME, id);
452 	if (!ppdev)
453 		return -ENOMEM;
454 
455 	/* Retain this platform_device pointer for later cleanup */
456 	priv->mii_pdev = ppdev;
457 	ppdev->dev.parent = &pdev->dev;
458 	ppdev->dev.of_node = bcmgenet_mii_of_find_mdio(priv);
459 	if (pdata)
460 		bcmgenet_mii_pdata_init(priv, &ppd);
461 
462 	ret = platform_device_add_resources(ppdev, &res, 1);
463 	if (ret)
464 		goto out;
465 
466 	ret = platform_device_add_data(ppdev, &ppd, sizeof(ppd));
467 	if (ret)
468 		goto out;
469 
470 	ret = platform_device_add(ppdev);
471 	if (ret)
472 		goto out;
473 
474 	return 0;
475 out:
476 	platform_device_put(ppdev);
477 	return ret;
478 }
479 
480 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
481 {
482 	struct device_node *dn = priv->pdev->dev.of_node;
483 	struct device *kdev = &priv->pdev->dev;
484 	struct phy_device *phydev;
485 	phy_interface_t phy_mode;
486 	int ret;
487 
488 	/* Fetch the PHY phandle */
489 	priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
490 
491 	/* In the case of a fixed PHY, the DT node associated
492 	 * to the PHY is the Ethernet MAC DT node.
493 	 */
494 	if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
495 		ret = of_phy_register_fixed_link(dn);
496 		if (ret)
497 			return ret;
498 
499 		priv->phy_dn = of_node_get(dn);
500 	}
501 
502 	/* Get the link mode */
503 	ret = of_get_phy_mode(dn, &phy_mode);
504 	if (ret) {
505 		dev_err(kdev, "invalid PHY mode property\n");
506 		return ret;
507 	}
508 
509 	priv->phy_interface = phy_mode;
510 
511 	/* We need to specifically look up whether this PHY interface is internal
512 	 * or not *before* we even try to probe the PHY driver over MDIO as we
513 	 * may have shut down the internal PHY for power saving purposes.
514 	 */
515 	if (priv->phy_interface == PHY_INTERFACE_MODE_INTERNAL)
516 		priv->internal_phy = true;
517 
518 	/* Make sure we initialize MoCA PHYs with a link down */
519 	if (phy_mode == PHY_INTERFACE_MODE_MOCA) {
520 		phydev = of_phy_find_device(dn);
521 		if (phydev) {
522 			phydev->link = 0;
523 			put_device(&phydev->mdio.dev);
524 		}
525 	}
526 
527 	return 0;
528 }
529 
530 static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)
531 {
532 	struct device *kdev = &priv->pdev->dev;
533 	struct bcmgenet_platform_data *pd = kdev->platform_data;
534 	char phy_name[MII_BUS_ID_SIZE + 3];
535 	char mdio_bus_id[MII_BUS_ID_SIZE];
536 	struct phy_device *phydev;
537 
538 	snprintf(mdio_bus_id, MII_BUS_ID_SIZE, "%s-%d",
539 		 UNIMAC_MDIO_DRV_NAME, priv->pdev->id);
540 
541 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
542 		snprintf(phy_name, MII_BUS_ID_SIZE, PHY_ID_FMT,
543 			 mdio_bus_id, pd->phy_address);
544 
545 		/*
546 		 * Internal or external PHY with MDIO access
547 		 */
548 		phydev = phy_attach(priv->dev, phy_name, pd->phy_interface);
549 		if (!phydev) {
550 			dev_err(kdev, "failed to register PHY device\n");
551 			return -ENODEV;
552 		}
553 	} else {
554 		/*
555 		 * MoCA port or no MDIO access.
556 		 * Use fixed PHY to represent the link layer.
557 		 */
558 		struct fixed_phy_status fphy_status = {
559 			.link = 1,
560 			.speed = pd->phy_speed,
561 			.duplex = pd->phy_duplex,
562 			.pause = 0,
563 			.asym_pause = 0,
564 		};
565 
566 		phydev = fixed_phy_register(PHY_POLL, &fphy_status, NULL);
567 		if (!phydev || IS_ERR(phydev)) {
568 			dev_err(kdev, "failed to register fixed PHY device\n");
569 			return -ENODEV;
570 		}
571 
572 		/* Make sure we initialize MoCA PHYs with a link down */
573 		phydev->link = 0;
574 
575 	}
576 
577 	priv->phy_interface = pd->phy_interface;
578 
579 	return 0;
580 }
581 
582 static int bcmgenet_mii_bus_init(struct bcmgenet_priv *priv)
583 {
584 	struct device_node *dn = priv->pdev->dev.of_node;
585 
586 	if (dn)
587 		return bcmgenet_mii_of_init(priv);
588 	else
589 		return bcmgenet_mii_pd_init(priv);
590 }
591 
592 int bcmgenet_mii_init(struct net_device *dev)
593 {
594 	struct bcmgenet_priv *priv = netdev_priv(dev);
595 	int ret;
596 
597 	ret = bcmgenet_mii_register(priv);
598 	if (ret)
599 		return ret;
600 
601 	ret = bcmgenet_mii_bus_init(priv);
602 	if (ret)
603 		goto out;
604 
605 	return 0;
606 
607 out:
608 	bcmgenet_mii_exit(dev);
609 	return ret;
610 }
611 
612 void bcmgenet_mii_exit(struct net_device *dev)
613 {
614 	struct bcmgenet_priv *priv = netdev_priv(dev);
615 	struct device_node *dn = priv->pdev->dev.of_node;
616 
617 	if (of_phy_is_fixed_link(dn))
618 		of_phy_deregister_fixed_link(dn);
619 	of_node_put(priv->phy_dn);
620 	platform_device_unregister(priv->mii_pdev);
621 }
622