1/*
2 * net/dsa/dsa.c - Hardware switch handling
3 * Copyright (c) 2008-2009 Marvell Semiconductor
4 * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
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 as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12#include <linux/list.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <linux/module.h>
16#include <net/dsa.h>
17#include <linux/of.h>
18#include <linux/of_mdio.h>
19#include <linux/of_platform.h>
20#include "dsa_priv.h"
21
22char dsa_driver_version[] = "0.1";
23
24
25/* switch driver registration ***********************************************/
26static DEFINE_MUTEX(dsa_switch_drivers_mutex);
27static LIST_HEAD(dsa_switch_drivers);
28
29void register_switch_driver(struct dsa_switch_driver *drv)
30{
31	mutex_lock(&dsa_switch_drivers_mutex);
32	list_add_tail(&drv->list, &dsa_switch_drivers);
33	mutex_unlock(&dsa_switch_drivers_mutex);
34}
35EXPORT_SYMBOL_GPL(register_switch_driver);
36
37void unregister_switch_driver(struct dsa_switch_driver *drv)
38{
39	mutex_lock(&dsa_switch_drivers_mutex);
40	list_del_init(&drv->list);
41	mutex_unlock(&dsa_switch_drivers_mutex);
42}
43EXPORT_SYMBOL_GPL(unregister_switch_driver);
44
45static struct dsa_switch_driver *
46dsa_switch_probe(struct device *host_dev, int sw_addr, char **_name)
47{
48	struct dsa_switch_driver *ret;
49	struct list_head *list;
50	char *name;
51
52	ret = NULL;
53	name = NULL;
54
55	mutex_lock(&dsa_switch_drivers_mutex);
56	list_for_each(list, &dsa_switch_drivers) {
57		struct dsa_switch_driver *drv;
58
59		drv = list_entry(list, struct dsa_switch_driver, list);
60
61		name = drv->probe(host_dev, sw_addr);
62		if (name != NULL) {
63			ret = drv;
64			break;
65		}
66	}
67	mutex_unlock(&dsa_switch_drivers_mutex);
68
69	*_name = name;
70
71	return ret;
72}
73
74
75/* basic switch operations **************************************************/
76static struct dsa_switch *
77dsa_switch_setup(struct dsa_switch_tree *dst, int index,
78		 struct device *parent, struct device *host_dev)
79{
80	struct dsa_chip_data *pd = dst->pd->chip + index;
81	struct dsa_switch_driver *drv;
82	struct dsa_switch *ds;
83	int ret;
84	char *name;
85	int i;
86	bool valid_name_found = false;
87
88	/*
89	 * Probe for switch model.
90	 */
91	drv = dsa_switch_probe(host_dev, pd->sw_addr, &name);
92	if (drv == NULL) {
93		printk(KERN_ERR "%s[%d]: could not detect attached switch\n",
94		       dst->master_netdev->name, index);
95		return ERR_PTR(-EINVAL);
96	}
97	printk(KERN_INFO "%s[%d]: detected a %s switch\n",
98		dst->master_netdev->name, index, name);
99
100
101	/*
102	 * Allocate and initialise switch state.
103	 */
104	ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
105	if (ds == NULL)
106		return ERR_PTR(-ENOMEM);
107
108	ds->dst = dst;
109	ds->index = index;
110	ds->pd = dst->pd->chip + index;
111	ds->drv = drv;
112	ds->master_dev = host_dev;
113
114	/*
115	 * Validate supplied switch configuration.
116	 */
117	for (i = 0; i < DSA_MAX_PORTS; i++) {
118		char *name;
119
120		name = pd->port_names[i];
121		if (name == NULL)
122			continue;
123
124		if (!strcmp(name, "cpu")) {
125			if (dst->cpu_switch != -1) {
126				printk(KERN_ERR "multiple cpu ports?!\n");
127				ret = -EINVAL;
128				goto out;
129			}
130			dst->cpu_switch = index;
131			dst->cpu_port = i;
132		} else if (!strcmp(name, "dsa")) {
133			ds->dsa_port_mask |= 1 << i;
134		} else {
135			ds->phys_port_mask |= 1 << i;
136		}
137		valid_name_found = true;
138	}
139
140	if (!valid_name_found && i == DSA_MAX_PORTS) {
141		ret = -EINVAL;
142		goto out;
143	}
144
145	/* Make the built-in MII bus mask match the number of ports,
146	 * switch drivers can override this later
147	 */
148	ds->phys_mii_mask = ds->phys_port_mask;
149
150	/*
151	 * If the CPU connects to this switch, set the switch tree
152	 * tagging protocol to the preferred tagging format of this
153	 * switch.
154	 */
155	if (dst->cpu_switch == index) {
156		switch (drv->tag_protocol) {
157#ifdef CONFIG_NET_DSA_TAG_DSA
158		case DSA_TAG_PROTO_DSA:
159			dst->rcv = dsa_netdev_ops.rcv;
160			break;
161#endif
162#ifdef CONFIG_NET_DSA_TAG_EDSA
163		case DSA_TAG_PROTO_EDSA:
164			dst->rcv = edsa_netdev_ops.rcv;
165			break;
166#endif
167#ifdef CONFIG_NET_DSA_TAG_TRAILER
168		case DSA_TAG_PROTO_TRAILER:
169			dst->rcv = trailer_netdev_ops.rcv;
170			break;
171#endif
172#ifdef CONFIG_NET_DSA_TAG_BRCM
173		case DSA_TAG_PROTO_BRCM:
174			dst->rcv = brcm_netdev_ops.rcv;
175			break;
176#endif
177		case DSA_TAG_PROTO_NONE:
178			break;
179		default:
180			ret = -ENOPROTOOPT;
181			goto out;
182		}
183
184		dst->tag_protocol = drv->tag_protocol;
185	}
186
187	/*
188	 * Do basic register setup.
189	 */
190	ret = drv->setup(ds);
191	if (ret < 0)
192		goto out;
193
194	ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
195	if (ret < 0)
196		goto out;
197
198	ds->slave_mii_bus = mdiobus_alloc();
199	if (ds->slave_mii_bus == NULL) {
200		ret = -ENOMEM;
201		goto out;
202	}
203	dsa_slave_mii_bus_init(ds);
204
205	ret = mdiobus_register(ds->slave_mii_bus);
206	if (ret < 0)
207		goto out_free;
208
209
210	/*
211	 * Create network devices for physical switch ports.
212	 */
213	for (i = 0; i < DSA_MAX_PORTS; i++) {
214		struct net_device *slave_dev;
215
216		if (!(ds->phys_port_mask & (1 << i)))
217			continue;
218
219		slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
220		if (slave_dev == NULL) {
221			printk(KERN_ERR "%s[%d]: can't create dsa "
222			       "slave device for port %d(%s)\n",
223			       dst->master_netdev->name,
224			       index, i, pd->port_names[i]);
225			continue;
226		}
227
228		ds->ports[i] = slave_dev;
229	}
230
231	return ds;
232
233out_free:
234	mdiobus_free(ds->slave_mii_bus);
235out:
236	kfree(ds);
237	return ERR_PTR(ret);
238}
239
240static void dsa_switch_destroy(struct dsa_switch *ds)
241{
242}
243
244#ifdef CONFIG_PM_SLEEP
245static int dsa_switch_suspend(struct dsa_switch *ds)
246{
247	int i, ret = 0;
248
249	/* Suspend slave network devices */
250	for (i = 0; i < DSA_MAX_PORTS; i++) {
251		if (!(ds->phys_port_mask & (1 << i)))
252			continue;
253
254		ret = dsa_slave_suspend(ds->ports[i]);
255		if (ret)
256			return ret;
257	}
258
259	if (ds->drv->suspend)
260		ret = ds->drv->suspend(ds);
261
262	return ret;
263}
264
265static int dsa_switch_resume(struct dsa_switch *ds)
266{
267	int i, ret = 0;
268
269	if (ds->drv->resume)
270		ret = ds->drv->resume(ds);
271
272	if (ret)
273		return ret;
274
275	/* Resume slave network devices */
276	for (i = 0; i < DSA_MAX_PORTS; i++) {
277		if (!(ds->phys_port_mask & (1 << i)))
278			continue;
279
280		ret = dsa_slave_resume(ds->ports[i]);
281		if (ret)
282			return ret;
283	}
284
285	return 0;
286}
287#endif
288
289
290/* link polling *************************************************************/
291static void dsa_link_poll_work(struct work_struct *ugly)
292{
293	struct dsa_switch_tree *dst;
294	int i;
295
296	dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
297
298	for (i = 0; i < dst->pd->nr_chips; i++) {
299		struct dsa_switch *ds = dst->ds[i];
300
301		if (ds != NULL && ds->drv->poll_link != NULL)
302			ds->drv->poll_link(ds);
303	}
304
305	mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
306}
307
308static void dsa_link_poll_timer(unsigned long _dst)
309{
310	struct dsa_switch_tree *dst = (void *)_dst;
311
312	schedule_work(&dst->link_poll_work);
313}
314
315
316/* platform driver init and cleanup *****************************************/
317static int dev_is_class(struct device *dev, void *class)
318{
319	if (dev->class != NULL && !strcmp(dev->class->name, class))
320		return 1;
321
322	return 0;
323}
324
325static struct device *dev_find_class(struct device *parent, char *class)
326{
327	if (dev_is_class(parent, class)) {
328		get_device(parent);
329		return parent;
330	}
331
332	return device_find_child(parent, class, dev_is_class);
333}
334
335struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
336{
337	struct device *d;
338
339	d = dev_find_class(dev, "mdio_bus");
340	if (d != NULL) {
341		struct mii_bus *bus;
342
343		bus = to_mii_bus(d);
344		put_device(d);
345
346		return bus;
347	}
348
349	return NULL;
350}
351EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
352
353static struct net_device *dev_to_net_device(struct device *dev)
354{
355	struct device *d;
356
357	d = dev_find_class(dev, "net");
358	if (d != NULL) {
359		struct net_device *nd;
360
361		nd = to_net_dev(d);
362		dev_hold(nd);
363		put_device(d);
364
365		return nd;
366	}
367
368	return NULL;
369}
370
371#ifdef CONFIG_OF
372static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
373					struct dsa_chip_data *cd,
374					int chip_index,
375					struct device_node *link)
376{
377	int ret;
378	const __be32 *reg;
379	int link_port_addr;
380	int link_sw_addr;
381	struct device_node *parent_sw;
382	int len;
383
384	parent_sw = of_get_parent(link);
385	if (!parent_sw)
386		return -EINVAL;
387
388	reg = of_get_property(parent_sw, "reg", &len);
389	if (!reg || (len != sizeof(*reg) * 2))
390		return -EINVAL;
391
392	link_sw_addr = be32_to_cpup(reg + 1);
393
394	if (link_sw_addr >= pd->nr_chips)
395		return -EINVAL;
396
397	/* First time routing table allocation */
398	if (!cd->rtable) {
399		cd->rtable = kmalloc(pd->nr_chips * sizeof(s8), GFP_KERNEL);
400		if (!cd->rtable)
401			return -ENOMEM;
402
403		/* default to no valid uplink/downlink */
404		memset(cd->rtable, -1, pd->nr_chips * sizeof(s8));
405	}
406
407	reg = of_get_property(link, "reg", NULL);
408	if (!reg) {
409		ret = -EINVAL;
410		goto out;
411	}
412
413	link_port_addr = be32_to_cpup(reg);
414
415	cd->rtable[link_sw_addr] = link_port_addr;
416
417	return 0;
418out:
419	kfree(cd->rtable);
420	return ret;
421}
422
423static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
424{
425	int i;
426	int port_index;
427
428	for (i = 0; i < pd->nr_chips; i++) {
429		port_index = 0;
430		while (port_index < DSA_MAX_PORTS) {
431			kfree(pd->chip[i].port_names[port_index]);
432			port_index++;
433		}
434		kfree(pd->chip[i].rtable);
435	}
436	kfree(pd->chip);
437}
438
439static int dsa_of_probe(struct platform_device *pdev)
440{
441	struct device_node *np = pdev->dev.of_node;
442	struct device_node *child, *mdio, *ethernet, *port, *link;
443	struct mii_bus *mdio_bus;
444	struct platform_device *ethernet_dev;
445	struct dsa_platform_data *pd;
446	struct dsa_chip_data *cd;
447	const char *port_name;
448	int chip_index, port_index;
449	const unsigned int *sw_addr, *port_reg;
450	int ret;
451
452	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
453	if (!mdio)
454		return -EINVAL;
455
456	mdio_bus = of_mdio_find_bus(mdio);
457	if (!mdio_bus)
458		return -EINVAL;
459
460	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
461	if (!ethernet)
462		return -EINVAL;
463
464	ethernet_dev = of_find_device_by_node(ethernet);
465	if (!ethernet_dev)
466		return -ENODEV;
467
468	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
469	if (!pd)
470		return -ENOMEM;
471
472	pdev->dev.platform_data = pd;
473	pd->netdev = &ethernet_dev->dev;
474	pd->nr_chips = of_get_child_count(np);
475	if (pd->nr_chips > DSA_MAX_SWITCHES)
476		pd->nr_chips = DSA_MAX_SWITCHES;
477
478	pd->chip = kzalloc(pd->nr_chips * sizeof(struct dsa_chip_data),
479			GFP_KERNEL);
480	if (!pd->chip) {
481		ret = -ENOMEM;
482		goto out_free;
483	}
484
485	chip_index = -1;
486	for_each_available_child_of_node(np, child) {
487		chip_index++;
488		cd = &pd->chip[chip_index];
489
490		cd->of_node = child;
491		cd->host_dev = &mdio_bus->dev;
492
493		sw_addr = of_get_property(child, "reg", NULL);
494		if (!sw_addr)
495			continue;
496
497		cd->sw_addr = be32_to_cpup(sw_addr);
498		if (cd->sw_addr > PHY_MAX_ADDR)
499			continue;
500
501		for_each_available_child_of_node(child, port) {
502			port_reg = of_get_property(port, "reg", NULL);
503			if (!port_reg)
504				continue;
505
506			port_index = be32_to_cpup(port_reg);
507
508			port_name = of_get_property(port, "label", NULL);
509			if (!port_name)
510				continue;
511
512			cd->port_dn[port_index] = port;
513
514			cd->port_names[port_index] = kstrdup(port_name,
515					GFP_KERNEL);
516			if (!cd->port_names[port_index]) {
517				ret = -ENOMEM;
518				goto out_free_chip;
519			}
520
521			link = of_parse_phandle(port, "link", 0);
522
523			if (!strcmp(port_name, "dsa") && link &&
524					pd->nr_chips > 1) {
525				ret = dsa_of_setup_routing_table(pd, cd,
526						chip_index, link);
527				if (ret)
528					goto out_free_chip;
529			}
530
531			if (port_index == DSA_MAX_PORTS)
532				break;
533		}
534	}
535
536	return 0;
537
538out_free_chip:
539	dsa_of_free_platform_data(pd);
540out_free:
541	kfree(pd);
542	pdev->dev.platform_data = NULL;
543	return ret;
544}
545
546static void dsa_of_remove(struct platform_device *pdev)
547{
548	struct dsa_platform_data *pd = pdev->dev.platform_data;
549
550	if (!pdev->dev.of_node)
551		return;
552
553	dsa_of_free_platform_data(pd);
554	kfree(pd);
555}
556#else
557static inline int dsa_of_probe(struct platform_device *pdev)
558{
559	return 0;
560}
561
562static inline void dsa_of_remove(struct platform_device *pdev)
563{
564}
565#endif
566
567static int dsa_probe(struct platform_device *pdev)
568{
569	static int dsa_version_printed;
570	struct dsa_platform_data *pd = pdev->dev.platform_data;
571	struct net_device *dev;
572	struct dsa_switch_tree *dst;
573	int i, ret;
574
575	if (!dsa_version_printed++)
576		printk(KERN_NOTICE "Distributed Switch Architecture "
577			"driver version %s\n", dsa_driver_version);
578
579	if (pdev->dev.of_node) {
580		ret = dsa_of_probe(pdev);
581		if (ret)
582			return ret;
583
584		pd = pdev->dev.platform_data;
585	}
586
587	if (pd == NULL || pd->netdev == NULL)
588		return -EINVAL;
589
590	dev = dev_to_net_device(pd->netdev);
591	if (dev == NULL) {
592		ret = -EINVAL;
593		goto out;
594	}
595
596	if (dev->dsa_ptr != NULL) {
597		dev_put(dev);
598		ret = -EEXIST;
599		goto out;
600	}
601
602	dst = kzalloc(sizeof(*dst), GFP_KERNEL);
603	if (dst == NULL) {
604		dev_put(dev);
605		ret = -ENOMEM;
606		goto out;
607	}
608
609	platform_set_drvdata(pdev, dst);
610
611	dst->pd = pd;
612	dst->master_netdev = dev;
613	dst->cpu_switch = -1;
614	dst->cpu_port = -1;
615
616	for (i = 0; i < pd->nr_chips; i++) {
617		struct dsa_switch *ds;
618
619		ds = dsa_switch_setup(dst, i, &pdev->dev, pd->chip[i].host_dev);
620		if (IS_ERR(ds)) {
621			printk(KERN_ERR "%s[%d]: couldn't create dsa switch "
622				"instance (error %ld)\n", dev->name, i,
623				PTR_ERR(ds));
624			continue;
625		}
626
627		dst->ds[i] = ds;
628		if (ds->drv->poll_link != NULL)
629			dst->link_poll_needed = 1;
630	}
631
632	/*
633	 * If we use a tagging format that doesn't have an ethertype
634	 * field, make sure that all packets from this point on get
635	 * sent to the tag format's receive function.
636	 */
637	wmb();
638	dev->dsa_ptr = (void *)dst;
639
640	if (dst->link_poll_needed) {
641		INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
642		init_timer(&dst->link_poll_timer);
643		dst->link_poll_timer.data = (unsigned long)dst;
644		dst->link_poll_timer.function = dsa_link_poll_timer;
645		dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
646		add_timer(&dst->link_poll_timer);
647	}
648
649	return 0;
650
651out:
652	dsa_of_remove(pdev);
653
654	return ret;
655}
656
657static int dsa_remove(struct platform_device *pdev)
658{
659	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
660	int i;
661
662	if (dst->link_poll_needed)
663		del_timer_sync(&dst->link_poll_timer);
664
665	flush_work(&dst->link_poll_work);
666
667	for (i = 0; i < dst->pd->nr_chips; i++) {
668		struct dsa_switch *ds = dst->ds[i];
669
670		if (ds != NULL)
671			dsa_switch_destroy(ds);
672	}
673
674	dsa_of_remove(pdev);
675
676	return 0;
677}
678
679static void dsa_shutdown(struct platform_device *pdev)
680{
681}
682
683static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
684			  struct packet_type *pt, struct net_device *orig_dev)
685{
686	struct dsa_switch_tree *dst = dev->dsa_ptr;
687
688	if (unlikely(dst == NULL)) {
689		kfree_skb(skb);
690		return 0;
691	}
692
693	return dst->rcv(skb, dev, pt, orig_dev);
694}
695
696static struct packet_type dsa_pack_type __read_mostly = {
697	.type	= cpu_to_be16(ETH_P_XDSA),
698	.func	= dsa_switch_rcv,
699};
700
701#ifdef CONFIG_PM_SLEEP
702static int dsa_suspend(struct device *d)
703{
704	struct platform_device *pdev = to_platform_device(d);
705	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
706	int i, ret = 0;
707
708	for (i = 0; i < dst->pd->nr_chips; i++) {
709		struct dsa_switch *ds = dst->ds[i];
710
711		if (ds != NULL)
712			ret = dsa_switch_suspend(ds);
713	}
714
715	return ret;
716}
717
718static int dsa_resume(struct device *d)
719{
720	struct platform_device *pdev = to_platform_device(d);
721	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
722	int i, ret = 0;
723
724	for (i = 0; i < dst->pd->nr_chips; i++) {
725		struct dsa_switch *ds = dst->ds[i];
726
727		if (ds != NULL)
728			ret = dsa_switch_resume(ds);
729	}
730
731	return ret;
732}
733#endif
734
735static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
736
737static const struct of_device_id dsa_of_match_table[] = {
738	{ .compatible = "brcm,bcm7445-switch-v4.0" },
739	{ .compatible = "marvell,dsa", },
740	{}
741};
742MODULE_DEVICE_TABLE(of, dsa_of_match_table);
743
744static struct platform_driver dsa_driver = {
745	.probe		= dsa_probe,
746	.remove		= dsa_remove,
747	.shutdown	= dsa_shutdown,
748	.driver = {
749		.name	= "dsa",
750		.owner	= THIS_MODULE,
751		.of_match_table = dsa_of_match_table,
752		.pm	= &dsa_pm_ops,
753	},
754};
755
756static int __init dsa_init_module(void)
757{
758	int rc;
759
760	rc = platform_driver_register(&dsa_driver);
761	if (rc)
762		return rc;
763
764	dev_add_pack(&dsa_pack_type);
765
766	return 0;
767}
768module_init(dsa_init_module);
769
770static void __exit dsa_cleanup_module(void)
771{
772	dev_remove_pack(&dsa_pack_type);
773	platform_driver_unregister(&dsa_driver);
774}
775module_exit(dsa_cleanup_module);
776
777MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
778MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
779MODULE_LICENSE("GPL");
780MODULE_ALIAS("platform:dsa");
781