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v3.1
 
  1/*
  2 * Incremental bus scan, based on bus topology
  3 *
  4 * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
  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 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program; if not, write to the Free Software Foundation,
 18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 19 */
 20
 21#include <linux/bug.h>
 22#include <linux/errno.h>
 23#include <linux/firewire.h>
 24#include <linux/firewire-constants.h>
 25#include <linux/jiffies.h>
 26#include <linux/kernel.h>
 27#include <linux/list.h>
 28#include <linux/module.h>
 29#include <linux/slab.h>
 30#include <linux/spinlock.h>
 31
 32#include <linux/atomic.h>
 33#include <asm/byteorder.h>
 34#include <asm/system.h>
 35
 36#include "core.h"
 37
 38#define SELF_ID_PHY_ID(q)		(((q) >> 24) & 0x3f)
 39#define SELF_ID_EXTENDED(q)		(((q) >> 23) & 0x01)
 40#define SELF_ID_LINK_ON(q)		(((q) >> 22) & 0x01)
 41#define SELF_ID_GAP_COUNT(q)		(((q) >> 16) & 0x3f)
 42#define SELF_ID_PHY_SPEED(q)		(((q) >> 14) & 0x03)
 43#define SELF_ID_CONTENDER(q)		(((q) >> 11) & 0x01)
 44#define SELF_ID_PHY_INITIATOR(q)	(((q) >>  1) & 0x01)
 45#define SELF_ID_MORE_PACKETS(q)		(((q) >>  0) & 0x01)
 46
 47#define SELF_ID_EXT_SEQUENCE(q)		(((q) >> 20) & 0x07)
 48
 49#define SELFID_PORT_CHILD	0x3
 50#define SELFID_PORT_PARENT	0x2
 51#define SELFID_PORT_NCONN	0x1
 52#define SELFID_PORT_NONE	0x0
 53
 54static u32 *count_ports(u32 *sid, int *total_port_count, int *child_port_count)
 55{
 56	u32 q;
 57	int port_type, shift, seq;
 58
 59	*total_port_count = 0;
 60	*child_port_count = 0;
 61
 62	shift = 6;
 63	q = *sid;
 64	seq = 0;
 65
 66	while (1) {
 67		port_type = (q >> shift) & 0x03;
 68		switch (port_type) {
 69		case SELFID_PORT_CHILD:
 70			(*child_port_count)++;
 
 71		case SELFID_PORT_PARENT:
 72		case SELFID_PORT_NCONN:
 73			(*total_port_count)++;
 74		case SELFID_PORT_NONE:
 75			break;
 76		}
 77
 78		shift -= 2;
 79		if (shift == 0) {
 80			if (!SELF_ID_MORE_PACKETS(q))
 81				return sid + 1;
 82
 83			shift = 16;
 84			sid++;
 85			q = *sid;
 86
 87			/*
 88			 * Check that the extra packets actually are
 89			 * extended self ID packets and that the
 90			 * sequence numbers in the extended self ID
 91			 * packets increase as expected.
 92			 */
 93
 94			if (!SELF_ID_EXTENDED(q) ||
 95			    seq != SELF_ID_EXT_SEQUENCE(q))
 96				return NULL;
 97
 98			seq++;
 99		}
100	}
101}
102
103static int get_port_type(u32 *sid, int port_index)
104{
105	int index, shift;
106
107	index = (port_index + 5) / 8;
108	shift = 16 - ((port_index + 5) & 7) * 2;
109	return (sid[index] >> shift) & 0x03;
110}
111
112static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
113{
114	struct fw_node *node;
115
116	node = kzalloc(sizeof(*node) + port_count * sizeof(node->ports[0]),
117		       GFP_ATOMIC);
118	if (node == NULL)
119		return NULL;
120
121	node->color = color;
122	node->node_id = LOCAL_BUS | SELF_ID_PHY_ID(sid);
123	node->link_on = SELF_ID_LINK_ON(sid);
124	node->phy_speed = SELF_ID_PHY_SPEED(sid);
125	node->initiated_reset = SELF_ID_PHY_INITIATOR(sid);
126	node->port_count = port_count;
127
128	atomic_set(&node->ref_count, 1);
129	INIT_LIST_HEAD(&node->link);
130
131	return node;
132}
133
134/*
135 * Compute the maximum hop count for this node and it's children.  The
136 * maximum hop count is the maximum number of connections between any
137 * two nodes in the subtree rooted at this node.  We need this for
138 * setting the gap count.  As we build the tree bottom up in
139 * build_tree() below, this is fairly easy to do: for each node we
140 * maintain the max hop count and the max depth, ie the number of hops
141 * to the furthest leaf.  Computing the max hop count breaks down into
142 * two cases: either the path goes through this node, in which case
143 * the hop count is the sum of the two biggest child depths plus 2.
144 * Or it could be the case that the max hop path is entirely
145 * containted in a child tree, in which case the max hop count is just
146 * the max hop count of this child.
147 */
148static void update_hop_count(struct fw_node *node)
149{
150	int depths[2] = { -1, -1 };
151	int max_child_hops = 0;
152	int i;
153
154	for (i = 0; i < node->port_count; i++) {
155		if (node->ports[i] == NULL)
156			continue;
157
158		if (node->ports[i]->max_hops > max_child_hops)
159			max_child_hops = node->ports[i]->max_hops;
160
161		if (node->ports[i]->max_depth > depths[0]) {
162			depths[1] = depths[0];
163			depths[0] = node->ports[i]->max_depth;
164		} else if (node->ports[i]->max_depth > depths[1])
165			depths[1] = node->ports[i]->max_depth;
166	}
167
168	node->max_depth = depths[0] + 1;
169	node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
170}
171
172static inline struct fw_node *fw_node(struct list_head *l)
173{
174	return list_entry(l, struct fw_node, link);
175}
176
177/*
178 * This function builds the tree representation of the topology given
179 * by the self IDs from the latest bus reset.  During the construction
180 * of the tree, the function checks that the self IDs are valid and
181 * internally consistent.  On success this function returns the
182 * fw_node corresponding to the local card otherwise NULL.
183 */
184static struct fw_node *build_tree(struct fw_card *card,
185				  u32 *sid, int self_id_count)
186{
187	struct fw_node *node, *child, *local_node, *irm_node;
188	struct list_head stack, *h;
189	u32 *next_sid, *end, q;
190	int i, port_count, child_port_count, phy_id, parent_count, stack_depth;
191	int gap_count;
192	bool beta_repeaters_present;
193
194	local_node = NULL;
195	node = NULL;
196	INIT_LIST_HEAD(&stack);
197	stack_depth = 0;
198	end = sid + self_id_count;
199	phy_id = 0;
200	irm_node = NULL;
201	gap_count = SELF_ID_GAP_COUNT(*sid);
202	beta_repeaters_present = false;
203
204	while (sid < end) {
205		next_sid = count_ports(sid, &port_count, &child_port_count);
206
207		if (next_sid == NULL) {
208			fw_error("Inconsistent extended self IDs.\n");
209			return NULL;
210		}
211
212		q = *sid;
213		if (phy_id != SELF_ID_PHY_ID(q)) {
214			fw_error("PHY ID mismatch in self ID: %d != %d.\n",
215				 phy_id, SELF_ID_PHY_ID(q));
216			return NULL;
217		}
218
219		if (child_port_count > stack_depth) {
220			fw_error("Topology stack underflow\n");
221			return NULL;
222		}
223
224		/*
225		 * Seek back from the top of our stack to find the
226		 * start of the child nodes for this node.
227		 */
228		for (i = 0, h = &stack; i < child_port_count; i++)
229			h = h->prev;
230		/*
231		 * When the stack is empty, this yields an invalid value,
232		 * but that pointer will never be dereferenced.
233		 */
234		child = fw_node(h);
235
236		node = fw_node_create(q, port_count, card->color);
237		if (node == NULL) {
238			fw_error("Out of memory while building topology.\n");
239			return NULL;
240		}
241
242		if (phy_id == (card->node_id & 0x3f))
243			local_node = node;
244
245		if (SELF_ID_CONTENDER(q))
246			irm_node = node;
247
248		parent_count = 0;
249
250		for (i = 0; i < port_count; i++) {
251			switch (get_port_type(sid, i)) {
252			case SELFID_PORT_PARENT:
253				/*
254				 * Who's your daddy?  We dont know the
255				 * parent node at this time, so we
256				 * temporarily abuse node->color for
257				 * remembering the entry in the
258				 * node->ports array where the parent
259				 * node should be.  Later, when we
260				 * handle the parent node, we fix up
261				 * the reference.
262				 */
263				parent_count++;
264				node->color = i;
265				break;
266
267			case SELFID_PORT_CHILD:
268				node->ports[i] = child;
269				/*
270				 * Fix up parent reference for this
271				 * child node.
272				 */
273				child->ports[child->color] = node;
274				child->color = card->color;
275				child = fw_node(child->link.next);
276				break;
277			}
278		}
279
280		/*
281		 * Check that the node reports exactly one parent
282		 * port, except for the root, which of course should
283		 * have no parents.
284		 */
285		if ((next_sid == end && parent_count != 0) ||
286		    (next_sid < end && parent_count != 1)) {
287			fw_error("Parent port inconsistency for node %d: "
288				 "parent_count=%d\n", phy_id, parent_count);
289			return NULL;
290		}
291
292		/* Pop the child nodes off the stack and push the new node. */
293		__list_del(h->prev, &stack);
294		list_add_tail(&node->link, &stack);
295		stack_depth += 1 - child_port_count;
296
297		if (node->phy_speed == SCODE_BETA &&
298		    parent_count + child_port_count > 1)
299			beta_repeaters_present = true;
300
301		/*
302		 * If PHYs report different gap counts, set an invalid count
303		 * which will force a gap count reconfiguration and a reset.
304		 */
305		if (SELF_ID_GAP_COUNT(q) != gap_count)
306			gap_count = 0;
307
308		update_hop_count(node);
309
310		sid = next_sid;
311		phy_id++;
312	}
313
314	card->root_node = node;
315	card->irm_node = irm_node;
316	card->gap_count = gap_count;
317	card->beta_repeaters_present = beta_repeaters_present;
318
319	return local_node;
320}
321
322typedef void (*fw_node_callback_t)(struct fw_card * card,
323				   struct fw_node * node,
324				   struct fw_node * parent);
325
326static void for_each_fw_node(struct fw_card *card, struct fw_node *root,
327			     fw_node_callback_t callback)
328{
329	struct list_head list;
330	struct fw_node *node, *next, *child, *parent;
331	int i;
332
333	INIT_LIST_HEAD(&list);
334
335	fw_node_get(root);
336	list_add_tail(&root->link, &list);
337	parent = NULL;
338	list_for_each_entry(node, &list, link) {
339		node->color = card->color;
340
341		for (i = 0; i < node->port_count; i++) {
342			child = node->ports[i];
343			if (!child)
344				continue;
345			if (child->color == card->color)
346				parent = child;
347			else {
348				fw_node_get(child);
349				list_add_tail(&child->link, &list);
350			}
351		}
352
353		callback(card, node, parent);
354	}
355
356	list_for_each_entry_safe(node, next, &list, link)
357		fw_node_put(node);
358}
359
360static void report_lost_node(struct fw_card *card,
361			     struct fw_node *node, struct fw_node *parent)
362{
363	fw_node_event(card, node, FW_NODE_DESTROYED);
364	fw_node_put(node);
365
366	/* Topology has changed - reset bus manager retry counter */
367	card->bm_retries = 0;
368}
369
370static void report_found_node(struct fw_card *card,
371			      struct fw_node *node, struct fw_node *parent)
372{
373	int b_path = (node->phy_speed == SCODE_BETA);
374
375	if (parent != NULL) {
376		/* min() macro doesn't work here with gcc 3.4 */
377		node->max_speed = parent->max_speed < node->phy_speed ?
378					parent->max_speed : node->phy_speed;
379		node->b_path = parent->b_path && b_path;
380	} else {
381		node->max_speed = node->phy_speed;
382		node->b_path = b_path;
383	}
384
385	fw_node_event(card, node, FW_NODE_CREATED);
386
387	/* Topology has changed - reset bus manager retry counter */
388	card->bm_retries = 0;
389}
390
391void fw_destroy_nodes(struct fw_card *card)
392{
393	unsigned long flags;
394
395	spin_lock_irqsave(&card->lock, flags);
396	card->color++;
397	if (card->local_node != NULL)
398		for_each_fw_node(card, card->local_node, report_lost_node);
399	card->local_node = NULL;
400	spin_unlock_irqrestore(&card->lock, flags);
401}
402
403static void move_tree(struct fw_node *node0, struct fw_node *node1, int port)
404{
405	struct fw_node *tree;
406	int i;
407
408	tree = node1->ports[port];
409	node0->ports[port] = tree;
410	for (i = 0; i < tree->port_count; i++) {
411		if (tree->ports[i] == node1) {
412			tree->ports[i] = node0;
413			break;
414		}
415	}
416}
417
418/*
419 * Compare the old topology tree for card with the new one specified by root.
420 * Queue the nodes and mark them as either found, lost or updated.
421 * Update the nodes in the card topology tree as we go.
422 */
423static void update_tree(struct fw_card *card, struct fw_node *root)
424{
425	struct list_head list0, list1;
426	struct fw_node *node0, *node1, *next1;
427	int i, event;
428
429	INIT_LIST_HEAD(&list0);
430	list_add_tail(&card->local_node->link, &list0);
431	INIT_LIST_HEAD(&list1);
432	list_add_tail(&root->link, &list1);
433
434	node0 = fw_node(list0.next);
435	node1 = fw_node(list1.next);
436
437	while (&node0->link != &list0) {
438		WARN_ON(node0->port_count != node1->port_count);
439
440		if (node0->link_on && !node1->link_on)
441			event = FW_NODE_LINK_OFF;
442		else if (!node0->link_on && node1->link_on)
443			event = FW_NODE_LINK_ON;
444		else if (node1->initiated_reset && node1->link_on)
445			event = FW_NODE_INITIATED_RESET;
446		else
447			event = FW_NODE_UPDATED;
448
449		node0->node_id = node1->node_id;
450		node0->color = card->color;
451		node0->link_on = node1->link_on;
452		node0->initiated_reset = node1->initiated_reset;
453		node0->max_hops = node1->max_hops;
454		node1->color = card->color;
455		fw_node_event(card, node0, event);
456
457		if (card->root_node == node1)
458			card->root_node = node0;
459		if (card->irm_node == node1)
460			card->irm_node = node0;
461
462		for (i = 0; i < node0->port_count; i++) {
463			if (node0->ports[i] && node1->ports[i]) {
464				/*
465				 * This port didn't change, queue the
466				 * connected node for further
467				 * investigation.
468				 */
469				if (node0->ports[i]->color == card->color)
470					continue;
471				list_add_tail(&node0->ports[i]->link, &list0);
472				list_add_tail(&node1->ports[i]->link, &list1);
473			} else if (node0->ports[i]) {
474				/*
475				 * The nodes connected here were
476				 * unplugged; unref the lost nodes and
477				 * queue FW_NODE_LOST callbacks for
478				 * them.
479				 */
480
481				for_each_fw_node(card, node0->ports[i],
482						 report_lost_node);
483				node0->ports[i] = NULL;
484			} else if (node1->ports[i]) {
485				/*
486				 * One or more node were connected to
487				 * this port. Move the new nodes into
488				 * the tree and queue FW_NODE_CREATED
489				 * callbacks for them.
490				 */
491				move_tree(node0, node1, i);
492				for_each_fw_node(card, node0->ports[i],
493						 report_found_node);
494			}
495		}
496
497		node0 = fw_node(node0->link.next);
498		next1 = fw_node(node1->link.next);
499		fw_node_put(node1);
500		node1 = next1;
501	}
502}
503
504static void update_topology_map(struct fw_card *card,
505				u32 *self_ids, int self_id_count)
506{
507	int node_count = (card->root_node->node_id & 0x3f) + 1;
508	__be32 *map = card->topology_map;
509
510	*map++ = cpu_to_be32((self_id_count + 2) << 16);
511	*map++ = cpu_to_be32(be32_to_cpu(card->topology_map[1]) + 1);
512	*map++ = cpu_to_be32((node_count << 16) | self_id_count);
513
514	while (self_id_count--)
515		*map++ = cpu_to_be32p(self_ids++);
516
517	fw_compute_block_crc(card->topology_map);
518}
519
520void fw_core_handle_bus_reset(struct fw_card *card, int node_id, int generation,
521			      int self_id_count, u32 *self_ids, bool bm_abdicate)
522{
523	struct fw_node *local_node;
524	unsigned long flags;
525
526	/*
527	 * If the selfID buffer is not the immediate successor of the
528	 * previously processed one, we cannot reliably compare the
529	 * old and new topologies.
530	 */
531	if (!is_next_generation(generation, card->generation) &&
532	    card->local_node != NULL) {
533		fw_notify("skipped bus generations, destroying all nodes\n");
534		fw_destroy_nodes(card);
535		card->bm_retries = 0;
536	}
537
538	spin_lock_irqsave(&card->lock, flags);
539
540	card->broadcast_channel_allocated = card->broadcast_channel_auto_allocated;
541	card->node_id = node_id;
542	/*
543	 * Update node_id before generation to prevent anybody from using
544	 * a stale node_id together with a current generation.
545	 */
546	smp_wmb();
547	card->generation = generation;
548	card->reset_jiffies = get_jiffies_64();
549	card->bm_node_id  = 0xffff;
550	card->bm_abdicate = bm_abdicate;
551	fw_schedule_bm_work(card, 0);
552
553	local_node = build_tree(card, self_ids, self_id_count);
554
555	update_topology_map(card, self_ids, self_id_count);
556
557	card->color++;
558
559	if (local_node == NULL) {
560		fw_error("topology build failed\n");
561		/* FIXME: We need to issue a bus reset in this case. */
562	} else if (card->local_node == NULL) {
563		card->local_node = local_node;
564		for_each_fw_node(card, local_node, report_found_node);
565	} else {
566		update_tree(card, local_node);
567	}
568
569	spin_unlock_irqrestore(&card->lock, flags);
570}
571EXPORT_SYMBOL(fw_core_handle_bus_reset);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Incremental bus scan, based on bus topology
  4 *
  5 * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  6 */
  7
  8#include <linux/bug.h>
  9#include <linux/errno.h>
 10#include <linux/firewire.h>
 11#include <linux/firewire-constants.h>
 12#include <linux/jiffies.h>
 13#include <linux/kernel.h>
 14#include <linux/list.h>
 15#include <linux/module.h>
 16#include <linux/slab.h>
 17#include <linux/spinlock.h>
 18
 19#include <linux/atomic.h>
 20#include <asm/byteorder.h>
 
 21
 22#include "core.h"
 23
 24#define SELF_ID_PHY_ID(q)		(((q) >> 24) & 0x3f)
 25#define SELF_ID_EXTENDED(q)		(((q) >> 23) & 0x01)
 26#define SELF_ID_LINK_ON(q)		(((q) >> 22) & 0x01)
 27#define SELF_ID_GAP_COUNT(q)		(((q) >> 16) & 0x3f)
 28#define SELF_ID_PHY_SPEED(q)		(((q) >> 14) & 0x03)
 29#define SELF_ID_CONTENDER(q)		(((q) >> 11) & 0x01)
 30#define SELF_ID_PHY_INITIATOR(q)	(((q) >>  1) & 0x01)
 31#define SELF_ID_MORE_PACKETS(q)		(((q) >>  0) & 0x01)
 32
 33#define SELF_ID_EXT_SEQUENCE(q)		(((q) >> 20) & 0x07)
 34
 35#define SELFID_PORT_CHILD	0x3
 36#define SELFID_PORT_PARENT	0x2
 37#define SELFID_PORT_NCONN	0x1
 38#define SELFID_PORT_NONE	0x0
 39
 40static u32 *count_ports(u32 *sid, int *total_port_count, int *child_port_count)
 41{
 42	u32 q;
 43	int port_type, shift, seq;
 44
 45	*total_port_count = 0;
 46	*child_port_count = 0;
 47
 48	shift = 6;
 49	q = *sid;
 50	seq = 0;
 51
 52	while (1) {
 53		port_type = (q >> shift) & 0x03;
 54		switch (port_type) {
 55		case SELFID_PORT_CHILD:
 56			(*child_port_count)++;
 57			/* fall through */
 58		case SELFID_PORT_PARENT:
 59		case SELFID_PORT_NCONN:
 60			(*total_port_count)++;
 61		case SELFID_PORT_NONE:
 62			break;
 63		}
 64
 65		shift -= 2;
 66		if (shift == 0) {
 67			if (!SELF_ID_MORE_PACKETS(q))
 68				return sid + 1;
 69
 70			shift = 16;
 71			sid++;
 72			q = *sid;
 73
 74			/*
 75			 * Check that the extra packets actually are
 76			 * extended self ID packets and that the
 77			 * sequence numbers in the extended self ID
 78			 * packets increase as expected.
 79			 */
 80
 81			if (!SELF_ID_EXTENDED(q) ||
 82			    seq != SELF_ID_EXT_SEQUENCE(q))
 83				return NULL;
 84
 85			seq++;
 86		}
 87	}
 88}
 89
 90static int get_port_type(u32 *sid, int port_index)
 91{
 92	int index, shift;
 93
 94	index = (port_index + 5) / 8;
 95	shift = 16 - ((port_index + 5) & 7) * 2;
 96	return (sid[index] >> shift) & 0x03;
 97}
 98
 99static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
100{
101	struct fw_node *node;
102
103	node = kzalloc(struct_size(node, ports, port_count), GFP_ATOMIC);
 
104	if (node == NULL)
105		return NULL;
106
107	node->color = color;
108	node->node_id = LOCAL_BUS | SELF_ID_PHY_ID(sid);
109	node->link_on = SELF_ID_LINK_ON(sid);
110	node->phy_speed = SELF_ID_PHY_SPEED(sid);
111	node->initiated_reset = SELF_ID_PHY_INITIATOR(sid);
112	node->port_count = port_count;
113
114	refcount_set(&node->ref_count, 1);
115	INIT_LIST_HEAD(&node->link);
116
117	return node;
118}
119
120/*
121 * Compute the maximum hop count for this node and it's children.  The
122 * maximum hop count is the maximum number of connections between any
123 * two nodes in the subtree rooted at this node.  We need this for
124 * setting the gap count.  As we build the tree bottom up in
125 * build_tree() below, this is fairly easy to do: for each node we
126 * maintain the max hop count and the max depth, ie the number of hops
127 * to the furthest leaf.  Computing the max hop count breaks down into
128 * two cases: either the path goes through this node, in which case
129 * the hop count is the sum of the two biggest child depths plus 2.
130 * Or it could be the case that the max hop path is entirely
131 * containted in a child tree, in which case the max hop count is just
132 * the max hop count of this child.
133 */
134static void update_hop_count(struct fw_node *node)
135{
136	int depths[2] = { -1, -1 };
137	int max_child_hops = 0;
138	int i;
139
140	for (i = 0; i < node->port_count; i++) {
141		if (node->ports[i] == NULL)
142			continue;
143
144		if (node->ports[i]->max_hops > max_child_hops)
145			max_child_hops = node->ports[i]->max_hops;
146
147		if (node->ports[i]->max_depth > depths[0]) {
148			depths[1] = depths[0];
149			depths[0] = node->ports[i]->max_depth;
150		} else if (node->ports[i]->max_depth > depths[1])
151			depths[1] = node->ports[i]->max_depth;
152	}
153
154	node->max_depth = depths[0] + 1;
155	node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
156}
157
158static inline struct fw_node *fw_node(struct list_head *l)
159{
160	return list_entry(l, struct fw_node, link);
161}
162
163/*
164 * This function builds the tree representation of the topology given
165 * by the self IDs from the latest bus reset.  During the construction
166 * of the tree, the function checks that the self IDs are valid and
167 * internally consistent.  On success this function returns the
168 * fw_node corresponding to the local card otherwise NULL.
169 */
170static struct fw_node *build_tree(struct fw_card *card,
171				  u32 *sid, int self_id_count)
172{
173	struct fw_node *node, *child, *local_node, *irm_node;
174	struct list_head stack, *h;
175	u32 *next_sid, *end, q;
176	int i, port_count, child_port_count, phy_id, parent_count, stack_depth;
177	int gap_count;
178	bool beta_repeaters_present;
179
180	local_node = NULL;
181	node = NULL;
182	INIT_LIST_HEAD(&stack);
183	stack_depth = 0;
184	end = sid + self_id_count;
185	phy_id = 0;
186	irm_node = NULL;
187	gap_count = SELF_ID_GAP_COUNT(*sid);
188	beta_repeaters_present = false;
189
190	while (sid < end) {
191		next_sid = count_ports(sid, &port_count, &child_port_count);
192
193		if (next_sid == NULL) {
194			fw_err(card, "inconsistent extended self IDs\n");
195			return NULL;
196		}
197
198		q = *sid;
199		if (phy_id != SELF_ID_PHY_ID(q)) {
200			fw_err(card, "PHY ID mismatch in self ID: %d != %d\n",
201			       phy_id, SELF_ID_PHY_ID(q));
202			return NULL;
203		}
204
205		if (child_port_count > stack_depth) {
206			fw_err(card, "topology stack underflow\n");
207			return NULL;
208		}
209
210		/*
211		 * Seek back from the top of our stack to find the
212		 * start of the child nodes for this node.
213		 */
214		for (i = 0, h = &stack; i < child_port_count; i++)
215			h = h->prev;
216		/*
217		 * When the stack is empty, this yields an invalid value,
218		 * but that pointer will never be dereferenced.
219		 */
220		child = fw_node(h);
221
222		node = fw_node_create(q, port_count, card->color);
223		if (node == NULL) {
224			fw_err(card, "out of memory while building topology\n");
225			return NULL;
226		}
227
228		if (phy_id == (card->node_id & 0x3f))
229			local_node = node;
230
231		if (SELF_ID_CONTENDER(q))
232			irm_node = node;
233
234		parent_count = 0;
235
236		for (i = 0; i < port_count; i++) {
237			switch (get_port_type(sid, i)) {
238			case SELFID_PORT_PARENT:
239				/*
240				 * Who's your daddy?  We dont know the
241				 * parent node at this time, so we
242				 * temporarily abuse node->color for
243				 * remembering the entry in the
244				 * node->ports array where the parent
245				 * node should be.  Later, when we
246				 * handle the parent node, we fix up
247				 * the reference.
248				 */
249				parent_count++;
250				node->color = i;
251				break;
252
253			case SELFID_PORT_CHILD:
254				node->ports[i] = child;
255				/*
256				 * Fix up parent reference for this
257				 * child node.
258				 */
259				child->ports[child->color] = node;
260				child->color = card->color;
261				child = fw_node(child->link.next);
262				break;
263			}
264		}
265
266		/*
267		 * Check that the node reports exactly one parent
268		 * port, except for the root, which of course should
269		 * have no parents.
270		 */
271		if ((next_sid == end && parent_count != 0) ||
272		    (next_sid < end && parent_count != 1)) {
273			fw_err(card, "parent port inconsistency for node %d: "
274			       "parent_count=%d\n", phy_id, parent_count);
275			return NULL;
276		}
277
278		/* Pop the child nodes off the stack and push the new node. */
279		__list_del(h->prev, &stack);
280		list_add_tail(&node->link, &stack);
281		stack_depth += 1 - child_port_count;
282
283		if (node->phy_speed == SCODE_BETA &&
284		    parent_count + child_port_count > 1)
285			beta_repeaters_present = true;
286
287		/*
288		 * If PHYs report different gap counts, set an invalid count
289		 * which will force a gap count reconfiguration and a reset.
290		 */
291		if (SELF_ID_GAP_COUNT(q) != gap_count)
292			gap_count = 0;
293
294		update_hop_count(node);
295
296		sid = next_sid;
297		phy_id++;
298	}
299
300	card->root_node = node;
301	card->irm_node = irm_node;
302	card->gap_count = gap_count;
303	card->beta_repeaters_present = beta_repeaters_present;
304
305	return local_node;
306}
307
308typedef void (*fw_node_callback_t)(struct fw_card * card,
309				   struct fw_node * node,
310				   struct fw_node * parent);
311
312static void for_each_fw_node(struct fw_card *card, struct fw_node *root,
313			     fw_node_callback_t callback)
314{
315	struct list_head list;
316	struct fw_node *node, *next, *child, *parent;
317	int i;
318
319	INIT_LIST_HEAD(&list);
320
321	fw_node_get(root);
322	list_add_tail(&root->link, &list);
323	parent = NULL;
324	list_for_each_entry(node, &list, link) {
325		node->color = card->color;
326
327		for (i = 0; i < node->port_count; i++) {
328			child = node->ports[i];
329			if (!child)
330				continue;
331			if (child->color == card->color)
332				parent = child;
333			else {
334				fw_node_get(child);
335				list_add_tail(&child->link, &list);
336			}
337		}
338
339		callback(card, node, parent);
340	}
341
342	list_for_each_entry_safe(node, next, &list, link)
343		fw_node_put(node);
344}
345
346static void report_lost_node(struct fw_card *card,
347			     struct fw_node *node, struct fw_node *parent)
348{
349	fw_node_event(card, node, FW_NODE_DESTROYED);
350	fw_node_put(node);
351
352	/* Topology has changed - reset bus manager retry counter */
353	card->bm_retries = 0;
354}
355
356static void report_found_node(struct fw_card *card,
357			      struct fw_node *node, struct fw_node *parent)
358{
359	int b_path = (node->phy_speed == SCODE_BETA);
360
361	if (parent != NULL) {
362		/* min() macro doesn't work here with gcc 3.4 */
363		node->max_speed = parent->max_speed < node->phy_speed ?
364					parent->max_speed : node->phy_speed;
365		node->b_path = parent->b_path && b_path;
366	} else {
367		node->max_speed = node->phy_speed;
368		node->b_path = b_path;
369	}
370
371	fw_node_event(card, node, FW_NODE_CREATED);
372
373	/* Topology has changed - reset bus manager retry counter */
374	card->bm_retries = 0;
375}
376
377void fw_destroy_nodes(struct fw_card *card)
378{
379	unsigned long flags;
380
381	spin_lock_irqsave(&card->lock, flags);
382	card->color++;
383	if (card->local_node != NULL)
384		for_each_fw_node(card, card->local_node, report_lost_node);
385	card->local_node = NULL;
386	spin_unlock_irqrestore(&card->lock, flags);
387}
388
389static void move_tree(struct fw_node *node0, struct fw_node *node1, int port)
390{
391	struct fw_node *tree;
392	int i;
393
394	tree = node1->ports[port];
395	node0->ports[port] = tree;
396	for (i = 0; i < tree->port_count; i++) {
397		if (tree->ports[i] == node1) {
398			tree->ports[i] = node0;
399			break;
400		}
401	}
402}
403
404/*
405 * Compare the old topology tree for card with the new one specified by root.
406 * Queue the nodes and mark them as either found, lost or updated.
407 * Update the nodes in the card topology tree as we go.
408 */
409static void update_tree(struct fw_card *card, struct fw_node *root)
410{
411	struct list_head list0, list1;
412	struct fw_node *node0, *node1, *next1;
413	int i, event;
414
415	INIT_LIST_HEAD(&list0);
416	list_add_tail(&card->local_node->link, &list0);
417	INIT_LIST_HEAD(&list1);
418	list_add_tail(&root->link, &list1);
419
420	node0 = fw_node(list0.next);
421	node1 = fw_node(list1.next);
422
423	while (&node0->link != &list0) {
424		WARN_ON(node0->port_count != node1->port_count);
425
426		if (node0->link_on && !node1->link_on)
427			event = FW_NODE_LINK_OFF;
428		else if (!node0->link_on && node1->link_on)
429			event = FW_NODE_LINK_ON;
430		else if (node1->initiated_reset && node1->link_on)
431			event = FW_NODE_INITIATED_RESET;
432		else
433			event = FW_NODE_UPDATED;
434
435		node0->node_id = node1->node_id;
436		node0->color = card->color;
437		node0->link_on = node1->link_on;
438		node0->initiated_reset = node1->initiated_reset;
439		node0->max_hops = node1->max_hops;
440		node1->color = card->color;
441		fw_node_event(card, node0, event);
442
443		if (card->root_node == node1)
444			card->root_node = node0;
445		if (card->irm_node == node1)
446			card->irm_node = node0;
447
448		for (i = 0; i < node0->port_count; i++) {
449			if (node0->ports[i] && node1->ports[i]) {
450				/*
451				 * This port didn't change, queue the
452				 * connected node for further
453				 * investigation.
454				 */
455				if (node0->ports[i]->color == card->color)
456					continue;
457				list_add_tail(&node0->ports[i]->link, &list0);
458				list_add_tail(&node1->ports[i]->link, &list1);
459			} else if (node0->ports[i]) {
460				/*
461				 * The nodes connected here were
462				 * unplugged; unref the lost nodes and
463				 * queue FW_NODE_LOST callbacks for
464				 * them.
465				 */
466
467				for_each_fw_node(card, node0->ports[i],
468						 report_lost_node);
469				node0->ports[i] = NULL;
470			} else if (node1->ports[i]) {
471				/*
472				 * One or more node were connected to
473				 * this port. Move the new nodes into
474				 * the tree and queue FW_NODE_CREATED
475				 * callbacks for them.
476				 */
477				move_tree(node0, node1, i);
478				for_each_fw_node(card, node0->ports[i],
479						 report_found_node);
480			}
481		}
482
483		node0 = fw_node(node0->link.next);
484		next1 = fw_node(node1->link.next);
485		fw_node_put(node1);
486		node1 = next1;
487	}
488}
489
490static void update_topology_map(struct fw_card *card,
491				u32 *self_ids, int self_id_count)
492{
493	int node_count = (card->root_node->node_id & 0x3f) + 1;
494	__be32 *map = card->topology_map;
495
496	*map++ = cpu_to_be32((self_id_count + 2) << 16);
497	*map++ = cpu_to_be32(be32_to_cpu(card->topology_map[1]) + 1);
498	*map++ = cpu_to_be32((node_count << 16) | self_id_count);
499
500	while (self_id_count--)
501		*map++ = cpu_to_be32p(self_ids++);
502
503	fw_compute_block_crc(card->topology_map);
504}
505
506void fw_core_handle_bus_reset(struct fw_card *card, int node_id, int generation,
507			      int self_id_count, u32 *self_ids, bool bm_abdicate)
508{
509	struct fw_node *local_node;
510	unsigned long flags;
511
512	/*
513	 * If the selfID buffer is not the immediate successor of the
514	 * previously processed one, we cannot reliably compare the
515	 * old and new topologies.
516	 */
517	if (!is_next_generation(generation, card->generation) &&
518	    card->local_node != NULL) {
 
519		fw_destroy_nodes(card);
520		card->bm_retries = 0;
521	}
522
523	spin_lock_irqsave(&card->lock, flags);
524
525	card->broadcast_channel_allocated = card->broadcast_channel_auto_allocated;
526	card->node_id = node_id;
527	/*
528	 * Update node_id before generation to prevent anybody from using
529	 * a stale node_id together with a current generation.
530	 */
531	smp_wmb();
532	card->generation = generation;
533	card->reset_jiffies = get_jiffies_64();
534	card->bm_node_id  = 0xffff;
535	card->bm_abdicate = bm_abdicate;
536	fw_schedule_bm_work(card, 0);
537
538	local_node = build_tree(card, self_ids, self_id_count);
539
540	update_topology_map(card, self_ids, self_id_count);
541
542	card->color++;
543
544	if (local_node == NULL) {
545		fw_err(card, "topology build failed\n");
546		/* FIXME: We need to issue a bus reset in this case. */
547	} else if (card->local_node == NULL) {
548		card->local_node = local_node;
549		for_each_fw_node(card, local_node, report_found_node);
550	} else {
551		update_tree(card, local_node);
552	}
553
554	spin_unlock_irqrestore(&card->lock, flags);
555}
556EXPORT_SYMBOL(fw_core_handle_bus_reset);