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-rw-r--r--drivers/firewire/fw-topology.c537
1 files changed, 537 insertions, 0 deletions
diff --git a/drivers/firewire/fw-topology.c b/drivers/firewire/fw-topology.c
new file mode 100644
index 000000000000..7aebb8ae0efa
--- /dev/null
+++ b/drivers/firewire/fw-topology.c
@@ -0,0 +1,537 @@
+/*
+ * Incremental bus scan, based on bus topology
+ *
+ * Copyright (C) 2004-2006 Kristian Hoegsberg <krh@bitplanet.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/module.h>
+#include <linux/wait.h>
+#include <linux/errno.h>
+#include "fw-transaction.h"
+#include "fw-topology.h"
+
+#define SELF_ID_PHY_ID(q) (((q) >> 24) & 0x3f)
+#define SELF_ID_EXTENDED(q) (((q) >> 23) & 0x01)
+#define SELF_ID_LINK_ON(q) (((q) >> 22) & 0x01)
+#define SELF_ID_GAP_COUNT(q) (((q) >> 16) & 0x3f)
+#define SELF_ID_PHY_SPEED(q) (((q) >> 14) & 0x03)
+#define SELF_ID_CONTENDER(q) (((q) >> 11) & 0x01)
+#define SELF_ID_PHY_INITIATOR(q) (((q) >> 1) & 0x01)
+#define SELF_ID_MORE_PACKETS(q) (((q) >> 0) & 0x01)
+
+#define SELF_ID_EXT_SEQUENCE(q) (((q) >> 20) & 0x07)
+
+static u32 *count_ports(u32 *sid, int *total_port_count, int *child_port_count)
+{
+ u32 q;
+ int port_type, shift, seq;
+
+ *total_port_count = 0;
+ *child_port_count = 0;
+
+ shift = 6;
+ q = *sid;
+ seq = 0;
+
+ while (1) {
+ port_type = (q >> shift) & 0x03;
+ switch (port_type) {
+ case SELFID_PORT_CHILD:
+ (*child_port_count)++;
+ case SELFID_PORT_PARENT:
+ case SELFID_PORT_NCONN:
+ (*total_port_count)++;
+ case SELFID_PORT_NONE:
+ break;
+ }
+
+ shift -= 2;
+ if (shift == 0) {
+ if (!SELF_ID_MORE_PACKETS(q))
+ return sid + 1;
+
+ shift = 16;
+ sid++;
+ q = *sid;
+
+ /*
+ * Check that the extra packets actually are
+ * extended self ID packets and that the
+ * sequence numbers in the extended self ID
+ * packets increase as expected.
+ */
+
+ if (!SELF_ID_EXTENDED(q) ||
+ seq != SELF_ID_EXT_SEQUENCE(q))
+ return NULL;
+
+ seq++;
+ }
+ }
+}
+
+static int get_port_type(u32 *sid, int port_index)
+{
+ int index, shift;
+
+ index = (port_index + 5) / 8;
+ shift = 16 - ((port_index + 5) & 7) * 2;
+ return (sid[index] >> shift) & 0x03;
+}
+
+static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
+{
+ struct fw_node *node;
+
+ node = kzalloc(sizeof(*node) + port_count * sizeof(node->ports[0]),
+ GFP_ATOMIC);
+ if (node == NULL)
+ return NULL;
+
+ node->color = color;
+ node->node_id = LOCAL_BUS | SELF_ID_PHY_ID(sid);
+ node->link_on = SELF_ID_LINK_ON(sid);
+ node->phy_speed = SELF_ID_PHY_SPEED(sid);
+ node->port_count = port_count;
+
+ atomic_set(&node->ref_count, 1);
+ INIT_LIST_HEAD(&node->link);
+
+ return node;
+}
+
+/*
+ * Compute the maximum hop count for this node and it's children. The
+ * maximum hop count is the maximum number of connections between any
+ * two nodes in the subtree rooted at this node. We need this for
+ * setting the gap count. As we build the tree bottom up in
+ * build_tree() below, this is fairly easy to do: for each node we
+ * maintain the max hop count and the max depth, ie the number of hops
+ * to the furthest leaf. Computing the max hop count breaks down into
+ * two cases: either the path goes through this node, in which case
+ * the hop count is the sum of the two biggest child depths plus 2.
+ * Or it could be the case that the max hop path is entirely
+ * containted in a child tree, in which case the max hop count is just
+ * the max hop count of this child.
+ */
+static void update_hop_count(struct fw_node *node)
+{
+ int depths[2] = { -1, -1 };
+ int max_child_hops = 0;
+ int i;
+
+ for (i = 0; i < node->port_count; i++) {
+ if (node->ports[i].node == NULL)
+ continue;
+
+ if (node->ports[i].node->max_hops > max_child_hops)
+ max_child_hops = node->ports[i].node->max_hops;
+
+ if (node->ports[i].node->max_depth > depths[0]) {
+ depths[1] = depths[0];
+ depths[0] = node->ports[i].node->max_depth;
+ } else if (node->ports[i].node->max_depth > depths[1])
+ depths[1] = node->ports[i].node->max_depth;
+ }
+
+ node->max_depth = depths[0] + 1;
+ node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
+}
+
+
+/**
+ * build_tree - Build the tree representation of the topology
+ * @self_ids: array of self IDs to create the tree from
+ * @self_id_count: the length of the self_ids array
+ * @local_id: the node ID of the local node
+ *
+ * This function builds the tree representation of the topology given
+ * by the self IDs from the latest bus reset. During the construction
+ * of the tree, the function checks that the self IDs are valid and
+ * internally consistent. On succcess this funtions returns the
+ * fw_node corresponding to the local card otherwise NULL.
+ */
+static struct fw_node *build_tree(struct fw_card *card,
+ u32 *sid, int self_id_count)
+{
+ struct fw_node *node, *child, *local_node, *irm_node;
+ struct list_head stack, *h;
+ u32 *next_sid, *end, q;
+ int i, port_count, child_port_count, phy_id, parent_count, stack_depth;
+ int gap_count, topology_type;
+
+ local_node = NULL;
+ node = NULL;
+ INIT_LIST_HEAD(&stack);
+ stack_depth = 0;
+ end = sid + self_id_count;
+ phy_id = 0;
+ irm_node = NULL;
+ gap_count = SELF_ID_GAP_COUNT(*sid);
+ topology_type = 0;
+
+ while (sid < end) {
+ next_sid = count_ports(sid, &port_count, &child_port_count);
+
+ if (next_sid == NULL) {
+ fw_error("Inconsistent extended self IDs.\n");
+ return NULL;
+ }
+
+ q = *sid;
+ if (phy_id != SELF_ID_PHY_ID(q)) {
+ fw_error("PHY ID mismatch in self ID: %d != %d.\n",
+ phy_id, SELF_ID_PHY_ID(q));
+ return NULL;
+ }
+
+ if (child_port_count > stack_depth) {
+ fw_error("Topology stack underflow\n");
+ return NULL;
+ }
+
+ /*
+ * Seek back from the top of our stack to find the
+ * start of the child nodes for this node.
+ */
+ for (i = 0, h = &stack; i < child_port_count; i++)
+ h = h->prev;
+ child = fw_node(h);
+
+ node = fw_node_create(q, port_count, card->color);
+ if (node == NULL) {
+ fw_error("Out of memory while building topology.");
+ return NULL;
+ }
+
+ if (phy_id == (card->node_id & 0x3f))
+ local_node = node;
+
+ if (SELF_ID_CONTENDER(q))
+ irm_node = node;
+
+ if (node->phy_speed == SCODE_BETA)
+ topology_type |= FW_TOPOLOGY_B;
+ else
+ topology_type |= FW_TOPOLOGY_A;
+
+ parent_count = 0;
+
+ for (i = 0; i < port_count; i++) {
+ switch (get_port_type(sid, i)) {
+ case SELFID_PORT_PARENT:
+ /*
+ * Who's your daddy? We dont know the
+ * parent node at this time, so we
+ * temporarily abuse node->color for
+ * remembering the entry in the
+ * node->ports array where the parent
+ * node should be. Later, when we
+ * handle the parent node, we fix up
+ * the reference.
+ */
+ parent_count++;
+ node->color = i;
+ break;
+
+ case SELFID_PORT_CHILD:
+ node->ports[i].node = child;
+ /*
+ * Fix up parent reference for this
+ * child node.
+ */
+ child->ports[child->color].node = node;
+ child->color = card->color;
+ child = fw_node(child->link.next);
+ break;
+ }
+ }
+
+ /*
+ * Check that the node reports exactly one parent
+ * port, except for the root, which of course should
+ * have no parents.
+ */
+ if ((next_sid == end && parent_count != 0) ||
+ (next_sid < end && parent_count != 1)) {
+ fw_error("Parent port inconsistency for node %d: "
+ "parent_count=%d\n", phy_id, parent_count);
+ return NULL;
+ }
+
+ /* Pop the child nodes off the stack and push the new node. */
+ __list_del(h->prev, &stack);
+ list_add_tail(&node->link, &stack);
+ stack_depth += 1 - child_port_count;
+
+ /*
+ * If all PHYs does not report the same gap count
+ * setting, we fall back to 63 which will force a gap
+ * count reconfiguration and a reset.
+ */
+ if (SELF_ID_GAP_COUNT(q) != gap_count)
+ gap_count = 63;
+
+ update_hop_count(node);
+
+ sid = next_sid;
+ phy_id++;
+ }
+
+ card->root_node = node;
+ card->irm_node = irm_node;
+ card->gap_count = gap_count;
+ card->topology_type = topology_type;
+
+ return local_node;
+}
+
+typedef void (*fw_node_callback_t)(struct fw_card * card,
+ struct fw_node * node,
+ struct fw_node * parent);
+
+static void
+for_each_fw_node(struct fw_card *card, struct fw_node *root,
+ fw_node_callback_t callback)
+{
+ struct list_head list;
+ struct fw_node *node, *next, *child, *parent;
+ int i;
+
+ INIT_LIST_HEAD(&list);
+
+ fw_node_get(root);
+ list_add_tail(&root->link, &list);
+ parent = NULL;
+ list_for_each_entry(node, &list, link) {
+ node->color = card->color;
+
+ for (i = 0; i < node->port_count; i++) {
+ child = node->ports[i].node;
+ if (!child)
+ continue;
+ if (child->color == card->color)
+ parent = child;
+ else {
+ fw_node_get(child);
+ list_add_tail(&child->link, &list);
+ }
+ }
+
+ callback(card, node, parent);
+ }
+
+ list_for_each_entry_safe(node, next, &list, link)
+ fw_node_put(node);
+}
+
+static void
+report_lost_node(struct fw_card *card,
+ struct fw_node *node, struct fw_node *parent)
+{
+ fw_node_event(card, node, FW_NODE_DESTROYED);
+ fw_node_put(node);
+}
+
+static void
+report_found_node(struct fw_card *card,
+ struct fw_node *node, struct fw_node *parent)
+{
+ int b_path = (node->phy_speed == SCODE_BETA);
+
+ if (parent != NULL) {
+ /* min() macro doesn't work here with gcc 3.4 */
+ node->max_speed = parent->max_speed < node->phy_speed ?
+ parent->max_speed : node->phy_speed;
+ node->b_path = parent->b_path && b_path;
+ } else {
+ node->max_speed = node->phy_speed;
+ node->b_path = b_path;
+ }
+
+ fw_node_event(card, node, FW_NODE_CREATED);
+}
+
+void fw_destroy_nodes(struct fw_card *card)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&card->lock, flags);
+ card->color++;
+ if (card->local_node != NULL)
+ for_each_fw_node(card, card->local_node, report_lost_node);
+ spin_unlock_irqrestore(&card->lock, flags);
+}
+
+static void move_tree(struct fw_node *node0, struct fw_node *node1, int port)
+{
+ struct fw_node *tree;
+ int i;
+
+ tree = node1->ports[port].node;
+ node0->ports[port].node = tree;
+ for (i = 0; i < tree->port_count; i++) {
+ if (tree->ports[i].node == node1) {
+ tree->ports[i].node = node0;
+ break;
+ }
+ }
+}
+
+/**
+ * update_tree - compare the old topology tree for card with the new
+ * one specified by root. Queue the nodes and mark them as either
+ * found, lost or updated. Update the nodes in the card topology tree
+ * as we go.
+ */
+static void
+update_tree(struct fw_card *card, struct fw_node *root)
+{
+ struct list_head list0, list1;
+ struct fw_node *node0, *node1;
+ int i, event;
+
+ INIT_LIST_HEAD(&list0);
+ list_add_tail(&card->local_node->link, &list0);
+ INIT_LIST_HEAD(&list1);
+ list_add_tail(&root->link, &list1);
+
+ node0 = fw_node(list0.next);
+ node1 = fw_node(list1.next);
+
+ while (&node0->link != &list0) {
+
+ /* assert(node0->port_count == node1->port_count); */
+ if (node0->link_on && !node1->link_on)
+ event = FW_NODE_LINK_OFF;
+ else if (!node0->link_on && node1->link_on)
+ event = FW_NODE_LINK_ON;
+ else
+ event = FW_NODE_UPDATED;
+
+ node0->node_id = node1->node_id;
+ node0->color = card->color;
+ node0->link_on = node1->link_on;
+ node0->initiated_reset = node1->initiated_reset;
+ node0->max_hops = node1->max_hops;
+ node1->color = card->color;
+ fw_node_event(card, node0, event);
+
+ if (card->root_node == node1)
+ card->root_node = node0;
+ if (card->irm_node == node1)
+ card->irm_node = node0;
+
+ for (i = 0; i < node0->port_count; i++) {
+ if (node0->ports[i].node && node1->ports[i].node) {
+ /*
+ * This port didn't change, queue the
+ * connected node for further
+ * investigation.
+ */
+ if (node0->ports[i].node->color == card->color)
+ continue;
+ list_add_tail(&node0->ports[i].node->link,
+ &list0);
+ list_add_tail(&node1->ports[i].node->link,
+ &list1);
+ } else if (node0->ports[i].node) {
+ /*
+ * The nodes connected here were
+ * unplugged; unref the lost nodes and
+ * queue FW_NODE_LOST callbacks for
+ * them.
+ */
+
+ for_each_fw_node(card, node0->ports[i].node,
+ report_lost_node);
+ node0->ports[i].node = NULL;
+ } else if (node1->ports[i].node) {
+ /*
+ * One or more node were connected to
+ * this port. Move the new nodes into
+ * the tree and queue FW_NODE_CREATED
+ * callbacks for them.
+ */
+ move_tree(node0, node1, i);
+ for_each_fw_node(card, node0->ports[i].node,
+ report_found_node);
+ }
+ }
+
+ node0 = fw_node(node0->link.next);
+ node1 = fw_node(node1->link.next);
+ }
+}
+
+static void
+update_topology_map(struct fw_card *card, u32 *self_ids, int self_id_count)
+{
+ int node_count;
+
+ card->topology_map[1]++;
+ node_count = (card->root_node->node_id & 0x3f) + 1;
+ card->topology_map[2] = (node_count << 16) | self_id_count;
+ card->topology_map[0] = (self_id_count + 2) << 16;
+ memcpy(&card->topology_map[3], self_ids, self_id_count * 4);
+ fw_compute_block_crc(card->topology_map);
+}
+
+void
+fw_core_handle_bus_reset(struct fw_card *card,
+ int node_id, int generation,
+ int self_id_count, u32 * self_ids)
+{
+ struct fw_node *local_node;
+ unsigned long flags;
+
+ fw_flush_transactions(card);
+
+ spin_lock_irqsave(&card->lock, flags);
+
+ /*
+ * If the new topology has a different self_id_count the topology
+ * changed, either nodes were added or removed. In that case we
+ * reset the IRM reset counter.
+ */
+ if (card->self_id_count != self_id_count)
+ card->bm_retries = 0;
+
+ card->node_id = node_id;
+ card->generation = generation;
+ card->reset_jiffies = jiffies;
+ schedule_delayed_work(&card->work, 0);
+
+ local_node = build_tree(card, self_ids, self_id_count);
+
+ update_topology_map(card, self_ids, self_id_count);
+
+ card->color++;
+
+ if (local_node == NULL) {
+ fw_error("topology build failed\n");
+ /* FIXME: We need to issue a bus reset in this case. */
+ } else if (card->local_node == NULL) {
+ card->local_node = local_node;
+ for_each_fw_node(card, local_node, report_found_node);
+ } else {
+ update_tree(card, local_node);
+ }
+
+ spin_unlock_irqrestore(&card->lock, flags);
+}
+EXPORT_SYMBOL(fw_core_handle_bus_reset);
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