2 * Incremental bus scan, based on bus topology
4 * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
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.
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.
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.
21 #include <linux/module.h>
22 #include <linux/wait.h>
23 #include <linux/errno.h>
25 #include <asm/system.h>
26 #include "fw-transaction.h"
27 #include "fw-topology.h"
29 #define SELF_ID_PHY_ID(q) (((q) >> 24) & 0x3f)
30 #define SELF_ID_EXTENDED(q) (((q) >> 23) & 0x01)
31 #define SELF_ID_LINK_ON(q) (((q) >> 22) & 0x01)
32 #define SELF_ID_GAP_COUNT(q) (((q) >> 16) & 0x3f)
33 #define SELF_ID_PHY_SPEED(q) (((q) >> 14) & 0x03)
34 #define SELF_ID_CONTENDER(q) (((q) >> 11) & 0x01)
35 #define SELF_ID_PHY_INITIATOR(q) (((q) >> 1) & 0x01)
36 #define SELF_ID_MORE_PACKETS(q) (((q) >> 0) & 0x01)
38 #define SELF_ID_EXT_SEQUENCE(q) (((q) >> 20) & 0x07)
40 static u32 *count_ports(u32 *sid, int *total_port_count, int *child_port_count)
43 int port_type, shift, seq;
45 *total_port_count = 0;
46 *child_port_count = 0;
53 port_type = (q >> shift) & 0x03;
55 case SELFID_PORT_CHILD:
56 (*child_port_count)++;
57 case SELFID_PORT_PARENT:
58 case SELFID_PORT_NCONN:
59 (*total_port_count)++;
60 case SELFID_PORT_NONE:
66 if (!SELF_ID_MORE_PACKETS(q))
74 * Check that the extra packets actually are
75 * extended self ID packets and that the
76 * sequence numbers in the extended self ID
77 * packets increase as expected.
80 if (!SELF_ID_EXTENDED(q) ||
81 seq != SELF_ID_EXT_SEQUENCE(q))
89 static int get_port_type(u32 *sid, int port_index)
93 index = (port_index + 5) / 8;
94 shift = 16 - ((port_index + 5) & 7) * 2;
95 return (sid[index] >> shift) & 0x03;
98 static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
100 struct fw_node *node;
102 node = kzalloc(sizeof(*node) + port_count * sizeof(node->ports[0]),
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;
114 atomic_set(&node->ref_count, 1);
115 INIT_LIST_HEAD(&node->link);
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.
134 static void update_hop_count(struct fw_node *node)
136 int depths[2] = { -1, -1 };
137 int max_child_hops = 0;
140 for (i = 0; i < node->port_count; i++) {
141 if (node->ports[i] == NULL)
144 if (node->ports[i]->max_hops > max_child_hops)
145 max_child_hops = node->ports[i]->max_hops;
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;
154 node->max_depth = depths[0] + 1;
155 node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
158 static inline struct fw_node *fw_node(struct list_head *l)
160 return list_entry(l, struct fw_node, link);
164 * build_tree - Build the tree representation of the topology
165 * @self_ids: array of self IDs to create the tree from
166 * @self_id_count: the length of the self_ids array
167 * @local_id: the node ID of the local node
169 * This function builds the tree representation of the topology given
170 * by the self IDs from the latest bus reset. During the construction
171 * of the tree, the function checks that the self IDs are valid and
172 * internally consistent. On succcess this function returns the
173 * fw_node corresponding to the local card otherwise NULL.
175 static struct fw_node *build_tree(struct fw_card *card,
176 u32 *sid, int self_id_count)
178 struct fw_node *node, *child, *local_node, *irm_node;
179 struct list_head stack, *h;
180 u32 *next_sid, *end, q;
181 int i, port_count, child_port_count, phy_id, parent_count, stack_depth;
183 bool beta_repeaters_present;
187 INIT_LIST_HEAD(&stack);
189 end = sid + self_id_count;
192 gap_count = SELF_ID_GAP_COUNT(*sid);
193 beta_repeaters_present = false;
196 next_sid = count_ports(sid, &port_count, &child_port_count);
198 if (next_sid == NULL) {
199 fw_error("Inconsistent extended self IDs.\n");
204 if (phy_id != SELF_ID_PHY_ID(q)) {
205 fw_error("PHY ID mismatch in self ID: %d != %d.\n",
206 phy_id, SELF_ID_PHY_ID(q));
210 if (child_port_count > stack_depth) {
211 fw_error("Topology stack underflow\n");
216 * Seek back from the top of our stack to find the
217 * start of the child nodes for this node.
219 for (i = 0, h = &stack; i < child_port_count; i++)
222 * When the stack is empty, this yields an invalid value,
223 * but that pointer will never be dereferenced.
227 node = fw_node_create(q, port_count, card->color);
229 fw_error("Out of memory while building topology.\n");
233 if (phy_id == (card->node_id & 0x3f))
236 if (SELF_ID_CONTENDER(q))
241 for (i = 0; i < port_count; i++) {
242 switch (get_port_type(sid, i)) {
243 case SELFID_PORT_PARENT:
245 * Who's your daddy? We dont know the
246 * parent node at this time, so we
247 * temporarily abuse node->color for
248 * remembering the entry in the
249 * node->ports array where the parent
250 * node should be. Later, when we
251 * handle the parent node, we fix up
258 case SELFID_PORT_CHILD:
259 node->ports[i] = child;
261 * Fix up parent reference for this
264 child->ports[child->color] = node;
265 child->color = card->color;
266 child = fw_node(child->link.next);
272 * Check that the node reports exactly one parent
273 * port, except for the root, which of course should
276 if ((next_sid == end && parent_count != 0) ||
277 (next_sid < end && parent_count != 1)) {
278 fw_error("Parent port inconsistency for node %d: "
279 "parent_count=%d\n", phy_id, parent_count);
283 /* Pop the child nodes off the stack and push the new node. */
284 __list_del(h->prev, &stack);
285 list_add_tail(&node->link, &stack);
286 stack_depth += 1 - child_port_count;
288 if (node->phy_speed == SCODE_BETA &&
289 parent_count + child_port_count > 1)
290 beta_repeaters_present = true;
293 * If all PHYs does not report the same gap count
294 * setting, we fall back to 63 which will force a gap
295 * count reconfiguration and a reset.
297 if (SELF_ID_GAP_COUNT(q) != gap_count)
300 update_hop_count(node);
306 card->root_node = node;
307 card->irm_node = irm_node;
308 card->gap_count = gap_count;
309 card->beta_repeaters_present = beta_repeaters_present;
314 typedef void (*fw_node_callback_t)(struct fw_card * card,
315 struct fw_node * node,
316 struct fw_node * parent);
319 for_each_fw_node(struct fw_card *card, struct fw_node *root,
320 fw_node_callback_t callback)
322 struct list_head list;
323 struct fw_node *node, *next, *child, *parent;
326 INIT_LIST_HEAD(&list);
329 list_add_tail(&root->link, &list);
331 list_for_each_entry(node, &list, link) {
332 node->color = card->color;
334 for (i = 0; i < node->port_count; i++) {
335 child = node->ports[i];
338 if (child->color == card->color)
342 list_add_tail(&child->link, &list);
346 callback(card, node, parent);
349 list_for_each_entry_safe(node, next, &list, link)
354 report_lost_node(struct fw_card *card,
355 struct fw_node *node, struct fw_node *parent)
357 fw_node_event(card, node, FW_NODE_DESTROYED);
362 report_found_node(struct fw_card *card,
363 struct fw_node *node, struct fw_node *parent)
365 int b_path = (node->phy_speed == SCODE_BETA);
367 if (parent != NULL) {
368 /* min() macro doesn't work here with gcc 3.4 */
369 node->max_speed = parent->max_speed < node->phy_speed ?
370 parent->max_speed : node->phy_speed;
371 node->b_path = parent->b_path && b_path;
373 node->max_speed = node->phy_speed;
374 node->b_path = b_path;
377 fw_node_event(card, node, FW_NODE_CREATED);
380 void fw_destroy_nodes(struct fw_card *card)
384 spin_lock_irqsave(&card->lock, flags);
386 if (card->local_node != NULL)
387 for_each_fw_node(card, card->local_node, report_lost_node);
388 card->local_node = NULL;
389 spin_unlock_irqrestore(&card->lock, flags);
392 static void move_tree(struct fw_node *node0, struct fw_node *node1, int port)
394 struct fw_node *tree;
397 tree = node1->ports[port];
398 node0->ports[port] = tree;
399 for (i = 0; i < tree->port_count; i++) {
400 if (tree->ports[i] == node1) {
401 tree->ports[i] = node0;
408 * update_tree - compare the old topology tree for card with the new
409 * one specified by root. Queue the nodes and mark them as either
410 * found, lost or updated. Update the nodes in the card topology tree
414 update_tree(struct fw_card *card, struct fw_node *root)
416 struct list_head list0, list1;
417 struct fw_node *node0, *node1;
420 INIT_LIST_HEAD(&list0);
421 list_add_tail(&card->local_node->link, &list0);
422 INIT_LIST_HEAD(&list1);
423 list_add_tail(&root->link, &list1);
425 node0 = fw_node(list0.next);
426 node1 = fw_node(list1.next);
428 while (&node0->link != &list0) {
429 WARN_ON(node0->port_count != node1->port_count);
431 if (node0->link_on && !node1->link_on)
432 event = FW_NODE_LINK_OFF;
433 else if (!node0->link_on && node1->link_on)
434 event = FW_NODE_LINK_ON;
435 else if (node1->initiated_reset && node1->link_on)
436 event = FW_NODE_INITIATED_RESET;
438 event = FW_NODE_UPDATED;
440 node0->node_id = node1->node_id;
441 node0->color = card->color;
442 node0->link_on = node1->link_on;
443 node0->initiated_reset = node1->initiated_reset;
444 node0->max_hops = node1->max_hops;
445 node1->color = card->color;
446 fw_node_event(card, node0, event);
448 if (card->root_node == node1)
449 card->root_node = node0;
450 if (card->irm_node == node1)
451 card->irm_node = node0;
453 for (i = 0; i < node0->port_count; i++) {
454 if (node0->ports[i] && node1->ports[i]) {
456 * This port didn't change, queue the
457 * connected node for further
460 if (node0->ports[i]->color == card->color)
462 list_add_tail(&node0->ports[i]->link, &list0);
463 list_add_tail(&node1->ports[i]->link, &list1);
464 } else if (node0->ports[i]) {
466 * The nodes connected here were
467 * unplugged; unref the lost nodes and
468 * queue FW_NODE_LOST callbacks for
472 for_each_fw_node(card, node0->ports[i],
474 node0->ports[i] = NULL;
475 } else if (node1->ports[i]) {
477 * One or more node were connected to
478 * this port. Move the new nodes into
479 * the tree and queue FW_NODE_CREATED
480 * callbacks for them.
482 move_tree(node0, node1, i);
483 for_each_fw_node(card, node0->ports[i],
488 node0 = fw_node(node0->link.next);
489 node1 = fw_node(node1->link.next);
494 update_topology_map(struct fw_card *card, u32 *self_ids, int self_id_count)
498 card->topology_map[1]++;
499 node_count = (card->root_node->node_id & 0x3f) + 1;
500 card->topology_map[2] = (node_count << 16) | self_id_count;
501 card->topology_map[0] = (self_id_count + 2) << 16;
502 memcpy(&card->topology_map[3], self_ids, self_id_count * 4);
503 fw_compute_block_crc(card->topology_map);
507 fw_core_handle_bus_reset(struct fw_card *card,
508 int node_id, int generation,
509 int self_id_count, u32 * self_ids)
511 struct fw_node *local_node;
514 fw_flush_transactions(card);
516 spin_lock_irqsave(&card->lock, flags);
519 * If the new topology has a different self_id_count the topology
520 * changed, either nodes were added or removed. In that case we
521 * reset the IRM reset counter.
523 if (card->self_id_count != self_id_count)
524 card->bm_retries = 0;
526 card->node_id = node_id;
528 * Update node_id before generation to prevent anybody from using
529 * a stale node_id together with a current generation.
532 card->generation = generation;
533 card->reset_jiffies = jiffies;
534 schedule_delayed_work(&card->work, 0);
536 local_node = build_tree(card, self_ids, self_id_count);
538 update_topology_map(card, self_ids, self_id_count);
542 if (local_node == NULL) {
543 fw_error("topology build failed\n");
544 /* FIXME: We need to issue a bus reset in this case. */
545 } else if (card->local_node == NULL) {
546 card->local_node = local_node;
547 for_each_fw_node(card, local_node, report_found_node);
549 update_tree(card, local_node);
552 spin_unlock_irqrestore(&card->lock, flags);
554 EXPORT_SYMBOL(fw_core_handle_bus_reset);