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 		reg |= id_mode_dis;
299 		if (GENET_IS_V1(priv) || GENET_IS_V2(priv) || GENET_IS_V3(priv))
300 			reg |= RGMII_MODE_EN_V123;
301 		else
302 			reg |= RGMII_MODE_EN;
303 		bcmgenet_ext_writel(priv, reg, EXT_RGMII_OOB_CTRL);
304 	}
305 
306 	if (init)
307 		dev_info(kdev, "configuring instance for %s\n", phy_name);
308 
309 	return 0;
310 }
311 
312 int bcmgenet_mii_probe(struct net_device *dev)
313 {
314 	struct bcmgenet_priv *priv = netdev_priv(dev);
315 	struct device_node *dn = priv->pdev->dev.of_node;
316 	struct phy_device *phydev;
317 	u32 phy_flags = 0;
318 	int ret;
319 
320 	/* Communicate the integrated PHY revision */
321 	if (priv->internal_phy)
322 		phy_flags = priv->gphy_rev;
323 
324 	/* Initialize link state variables that bcmgenet_mii_setup() uses */
325 	priv->old_link = -1;
326 	priv->old_speed = -1;
327 	priv->old_duplex = -1;
328 	priv->old_pause = -1;
329 
330 	if (dn) {
331 		phydev = of_phy_connect(dev, priv->phy_dn, bcmgenet_mii_setup,
332 					phy_flags, priv->phy_interface);
333 		if (!phydev) {
334 			pr_err("could not attach to PHY\n");
335 			return -ENODEV;
336 		}
337 	} else {
338 		phydev = dev->phydev;
339 		phydev->dev_flags = phy_flags;
340 
341 		ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
342 					 priv->phy_interface);
343 		if (ret) {
344 			pr_err("could not attach to PHY\n");
345 			return -ENODEV;
346 		}
347 	}
348 
349 	/* Configure port multiplexer based on what the probed PHY device since
350 	 * reading the 'max-speed' property determines the maximum supported
351 	 * PHY speed which is needed for bcmgenet_mii_config() to configure
352 	 * things appropriately.
353 	 */
354 	ret = bcmgenet_mii_config(dev, true);
355 	if (ret) {
356 		phy_disconnect(dev->phydev);
357 		return ret;
358 	}
359 
360 	linkmode_copy(phydev->advertising, phydev->supported);
361 
362 	/* The internal PHY has its link interrupts routed to the
363 	 * Ethernet MAC ISRs. On GENETv5 there is a hardware issue
364 	 * that prevents the signaling of link UP interrupts when
365 	 * the link operates at 10Mbps, so fallback to polling for
366 	 * those versions of GENET.
367 	 */
368 	if (priv->internal_phy && !GENET_IS_V5(priv))
369 		dev->phydev->irq = PHY_IGNORE_INTERRUPT;
370 
371 	return 0;
372 }
373 
374 static struct device_node *bcmgenet_mii_of_find_mdio(struct bcmgenet_priv *priv)
375 {
376 	struct device_node *dn = priv->pdev->dev.of_node;
377 	struct device *kdev = &priv->pdev->dev;
378 	char *compat;
379 
380 	compat = kasprintf(GFP_KERNEL, "brcm,genet-mdio-v%d", priv->version);
381 	if (!compat)
382 		return NULL;
383 
384 	priv->mdio_dn = of_get_compatible_child(dn, compat);
385 	kfree(compat);
386 	if (!priv->mdio_dn) {
387 		dev_err(kdev, "unable to find MDIO bus node\n");
388 		return NULL;
389 	}
390 
391 	return priv->mdio_dn;
392 }
393 
394 static void bcmgenet_mii_pdata_init(struct bcmgenet_priv *priv,
395 				    struct unimac_mdio_pdata *ppd)
396 {
397 	struct device *kdev = &priv->pdev->dev;
398 	struct bcmgenet_platform_data *pd = kdev->platform_data;
399 
400 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
401 		/*
402 		 * Internal or external PHY with MDIO access
403 		 */
404 		if (pd->phy_address >= 0 && pd->phy_address < PHY_MAX_ADDR)
405 			ppd->phy_mask = 1 << pd->phy_address;
406 		else
407 			ppd->phy_mask = 0;
408 	}
409 }
410 
411 static int bcmgenet_mii_wait(void *wait_func_data)
412 {
413 	struct bcmgenet_priv *priv = wait_func_data;
414 
415 	wait_event_timeout(priv->wq,
416 			   !(bcmgenet_umac_readl(priv, UMAC_MDIO_CMD)
417 			   & MDIO_START_BUSY),
418 			   HZ / 100);
419 	return 0;
420 }
421 
422 static int bcmgenet_mii_register(struct bcmgenet_priv *priv)
423 {
424 	struct platform_device *pdev = priv->pdev;
425 	struct bcmgenet_platform_data *pdata = pdev->dev.platform_data;
426 	struct device_node *dn = pdev->dev.of_node;
427 	struct unimac_mdio_pdata ppd;
428 	struct platform_device *ppdev;
429 	struct resource *pres, res;
430 	int id, ret;
431 
432 	pres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
433 	memset(&res, 0, sizeof(res));
434 	memset(&ppd, 0, sizeof(ppd));
435 
436 	ppd.wait_func = bcmgenet_mii_wait;
437 	ppd.wait_func_data = priv;
438 	ppd.bus_name = "bcmgenet MII bus";
439 
440 	/* Unimac MDIO bus controller starts at UniMAC offset + MDIO_CMD
441 	 * and is 2 * 32-bits word long, 8 bytes total.
442 	 */
443 	res.start = pres->start + GENET_UMAC_OFF + UMAC_MDIO_CMD;
444 	res.end = res.start + 8;
445 	res.flags = IORESOURCE_MEM;
446 
447 	if (dn)
448 		id = of_alias_get_id(dn, "eth");
449 	else
450 		id = pdev->id;
451 
452 	ppdev = platform_device_alloc(UNIMAC_MDIO_DRV_NAME, id);
453 	if (!ppdev)
454 		return -ENOMEM;
455 
456 	/* Retain this platform_device pointer for later cleanup */
457 	priv->mii_pdev = ppdev;
458 	ppdev->dev.parent = &pdev->dev;
459 	ppdev->dev.of_node = bcmgenet_mii_of_find_mdio(priv);
460 	if (pdata)
461 		bcmgenet_mii_pdata_init(priv, &ppd);
462 
463 	ret = platform_device_add_resources(ppdev, &res, 1);
464 	if (ret)
465 		goto out;
466 
467 	ret = platform_device_add_data(ppdev, &ppd, sizeof(ppd));
468 	if (ret)
469 		goto out;
470 
471 	ret = platform_device_add(ppdev);
472 	if (ret)
473 		goto out;
474 
475 	return 0;
476 out:
477 	platform_device_put(ppdev);
478 	return ret;
479 }
480 
481 static int bcmgenet_mii_of_init(struct bcmgenet_priv *priv)
482 {
483 	struct device_node *dn = priv->pdev->dev.of_node;
484 	struct device *kdev = &priv->pdev->dev;
485 	struct phy_device *phydev;
486 	phy_interface_t phy_mode;
487 	int ret;
488 
489 	/* Fetch the PHY phandle */
490 	priv->phy_dn = of_parse_phandle(dn, "phy-handle", 0);
491 
492 	/* In the case of a fixed PHY, the DT node associated
493 	 * to the PHY is the Ethernet MAC DT node.
494 	 */
495 	if (!priv->phy_dn && of_phy_is_fixed_link(dn)) {
496 		ret = of_phy_register_fixed_link(dn);
497 		if (ret)
498 			return ret;
499 
500 		priv->phy_dn = of_node_get(dn);
501 	}
502 
503 	/* Get the link mode */
504 	ret = of_get_phy_mode(dn, &phy_mode);
505 	if (ret) {
506 		dev_err(kdev, "invalid PHY mode property\n");
507 		return ret;
508 	}
509 
510 	priv->phy_interface = phy_mode;
511 
512 	/* We need to specifically look up whether this PHY interface is internal
513 	 * or not *before* we even try to probe the PHY driver over MDIO as we
514 	 * may have shut down the internal PHY for power saving purposes.
515 	 */
516 	if (priv->phy_interface == PHY_INTERFACE_MODE_INTERNAL)
517 		priv->internal_phy = true;
518 
519 	/* Make sure we initialize MoCA PHYs with a link down */
520 	if (phy_mode == PHY_INTERFACE_MODE_MOCA) {
521 		phydev = of_phy_find_device(dn);
522 		if (phydev) {
523 			phydev->link = 0;
524 			put_device(&phydev->mdio.dev);
525 		}
526 	}
527 
528 	return 0;
529 }
530 
531 static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)
532 {
533 	struct device *kdev = &priv->pdev->dev;
534 	struct bcmgenet_platform_data *pd = kdev->platform_data;
535 	char phy_name[MII_BUS_ID_SIZE + 3];
536 	char mdio_bus_id[MII_BUS_ID_SIZE];
537 	struct phy_device *phydev;
538 
539 	snprintf(mdio_bus_id, MII_BUS_ID_SIZE, "%s-%d",
540 		 UNIMAC_MDIO_DRV_NAME, priv->pdev->id);
541 
542 	if (pd->phy_interface != PHY_INTERFACE_MODE_MOCA && pd->mdio_enabled) {
543 		snprintf(phy_name, MII_BUS_ID_SIZE, PHY_ID_FMT,
544 			 mdio_bus_id, pd->phy_address);
545 
546 		/*
547 		 * Internal or external PHY with MDIO access
548 		 */
549 		phydev = phy_attach(priv->dev, phy_name, pd->phy_interface);
550 		if (!phydev) {
551 			dev_err(kdev, "failed to register PHY device\n");
552 			return -ENODEV;
553 		}
554 	} else {
555 		/*
556 		 * MoCA port or no MDIO access.
557 		 * Use fixed PHY to represent the link layer.
558 		 */
559 		struct fixed_phy_status fphy_status = {
560 			.link = 1,
561 			.speed = pd->phy_speed,
562 			.duplex = pd->phy_duplex,
563 			.pause = 0,
564 			.asym_pause = 0,
565 		};
566 
567 		phydev = fixed_phy_register(PHY_POLL, &fphy_status, NULL);
568 		if (!phydev || IS_ERR(phydev)) {
569 			dev_err(kdev, "failed to register fixed PHY device\n");
570 			return -ENODEV;
571 		}
572 
573 		/* Make sure we initialize MoCA PHYs with a link down */
574 		phydev->link = 0;
575 
576 	}
577 
578 	priv->phy_interface = pd->phy_interface;
579 
580 	return 0;
581 }
582 
583 static int bcmgenet_mii_bus_init(struct bcmgenet_priv *priv)
584 {
585 	struct device_node *dn = priv->pdev->dev.of_node;
586 
587 	if (dn)
588 		return bcmgenet_mii_of_init(priv);
589 	else
590 		return bcmgenet_mii_pd_init(priv);
591 }
592 
593 int bcmgenet_mii_init(struct net_device *dev)
594 {
595 	struct bcmgenet_priv *priv = netdev_priv(dev);
596 	int ret;
597 
598 	ret = bcmgenet_mii_register(priv);
599 	if (ret)
600 		return ret;
601 
602 	ret = bcmgenet_mii_bus_init(priv);
603 	if (ret)
604 		goto out;
605 
606 	return 0;
607 
608 out:
609 	bcmgenet_mii_exit(dev);
610 	return ret;
611 }
612 
613 void bcmgenet_mii_exit(struct net_device *dev)
614 {
615 	struct bcmgenet_priv *priv = netdev_priv(dev);
616 	struct device_node *dn = priv->pdev->dev.of_node;
617 
618 	if (of_phy_is_fixed_link(dn))
619 		of_phy_deregister_fixed_link(dn);
620 	of_node_put(priv->phy_dn);
621 	platform_device_unregister(priv->mii_pdev);
622 }
623