[thirdparty/kernel/stable.git] / drivers / firewire / core-topology.c

/*
 * 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/bug.h>
#include <linux/errno.h>
#include <linux/firewire.h>
#include <linux/firewire-constants.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spinlock.h>

#include <linux/atomic.h>
#include <asm/byteorder.h>

#include "core.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)

#define SELFID_PORT_CHILD	0x3
#define SELFID_PORT_PARENT	0x2
#define SELFID_PORT_NCONN	0x1
#define SELFID_PORT_NONE	0x0

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(struct_size(node, ports, port_count), 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->initiated_reset = SELF_ID_PHY_INITIATOR(sid);
	node->port_count = port_count;

	refcount_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] == NULL)
			continue;

		if (node->ports[i]->max_hops > max_child_hops)
			max_child_hops = node->ports[i]->max_hops;

		if (node->ports[i]->max_depth > depths[0]) {
			depths[1] = depths[0];
			depths[0] = node->ports[i]->max_depth;
		} else if (node->ports[i]->max_depth > depths[1])
			depths[1] = node->ports[i]->max_depth;
	}

	node->max_depth = depths[0] + 1;
	node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
}

static inline struct fw_node *fw_node(struct list_head *l)
{
	return list_entry(l, struct fw_node, link);
}

/*
 * 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 success this function 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;
	bool beta_repeaters_present;

	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);
	beta_repeaters_present = false;

	while (sid < end) {
		next_sid = count_ports(sid, &port_count, &child_port_count);

		if (next_sid == NULL) {
			fw_err(card, "inconsistent extended self IDs\n");
			return NULL;
		}

		q = *sid;
		if (phy_id != SELF_ID_PHY_ID(q)) {
			fw_err(card, "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_err(card, "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;
		/*
		 * When the stack is empty, this yields an invalid value,
		 * but that pointer will never be dereferenced.
		 */
		child = fw_node(h);

		node = fw_node_create(q, port_count, card->color);
		if (node == NULL) {
			fw_err(card, "out of memory while building topology\n");
			return NULL;
		}

		if (phy_id == (card->node_id & 0x3f))
			local_node = node;

		if (SELF_ID_CONTENDER(q))
			irm_node = node;

		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] = child;
				/*
				 * Fix up parent reference for this
				 * child node.
				 */
				child->ports[child->color] = 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_err(card, "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 (node->phy_speed == SCODE_BETA &&
		    parent_count + child_port_count > 1)
			beta_repeaters_present = true;

		/*
		 * If PHYs report different gap counts, set an invalid count
		 * which will force a gap count reconfiguration and a reset.
		 */
		if (SELF_ID_GAP_COUNT(q) != gap_count)
			gap_count = 0;

		update_hop_count(node);

		sid = next_sid;
		phy_id++;
	}

	card->root_node = node;
	card->irm_node = irm_node;
	card->gap_count = gap_count;
	card->beta_repeaters_present = beta_repeaters_present;

	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];
			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);

	/* Topology has changed - reset bus manager retry counter */
	card->bm_retries = 0;
}

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);

	/* Topology has changed - reset bus manager retry counter */
	card->bm_retries = 0;
}

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);
	card->local_node = NULL;
	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];
	node0->ports[port] = tree;
	for (i = 0; i < tree->port_count; i++) {
		if (tree->ports[i] == node1) {
			tree->ports[i] = node0;
			break;
		}
	}
}

/*
 * 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, *next1;
	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) {
		WARN_ON(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 if (node1->initiated_reset && node1->link_on)
			event = FW_NODE_INITIATED_RESET;
		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] && node1->ports[i]) {
				/*
				 * This port didn't change, queue the
				 * connected node for further
				 * investigation.
				 */
				if (node0->ports[i]->color == card->color)
					continue;
				list_add_tail(&node0->ports[i]->link, &list0);
				list_add_tail(&node1->ports[i]->link, &list1);
			} else if (node0->ports[i]) {
				/*
				 * 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],
						 report_lost_node);
				node0->ports[i] = NULL;
			} else if (node1->ports[i]) {
				/*
				 * 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],
						 report_found_node);
			}
		}

		node0 = fw_node(node0->link.next);
		next1 = fw_node(node1->link.next);
		fw_node_put(node1);
		node1 = next1;
	}
}

static void update_topology_map(struct fw_card *card,
				u32 *self_ids, int self_id_count)
{
	int node_count = (card->root_node->node_id & 0x3f) + 1;
	__be32 *map = card->topology_map;

	*map++ = cpu_to_be32((self_id_count + 2) << 16);
	*map++ = cpu_to_be32(be32_to_cpu(card->topology_map[1]) + 1);
	*map++ = cpu_to_be32((node_count << 16) | self_id_count);

	while (self_id_count--)
		*map++ = cpu_to_be32p(self_ids++);

	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, bool bm_abdicate)
{
	struct fw_node *local_node;
	unsigned long flags;

	/*
	 * If the selfID buffer is not the immediate successor of the
	 * previously processed one, we cannot reliably compare the
	 * old and new topologies.
	 */
	if (!is_next_generation(generation, card->generation) &&
	    card->local_node != NULL) {
		fw_destroy_nodes(card);
		card->bm_retries = 0;
	}

	spin_lock_irqsave(&card->lock, flags);

	card->broadcast_channel_allocated = card->broadcast_channel_auto_allocated;
	card->node_id = node_id;
	/*
	 * Update node_id before generation to prevent anybody from using
	 * a stale node_id together with a current generation.
	 */
	smp_wmb();
	card->generation = generation;
	card->reset_jiffies = get_jiffies_64();
	card->bm_node_id  = 0xffff;
	card->bm_abdicate = bm_abdicate;
	fw_schedule_bm_work(card, 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_err(card, "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);
Commit	Line	Data
c781c06d KH	1	/*
c781c06d KH	2	* Incremental bus scan, based on bus topology
3038e353 KH	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
e8ca9702	21	#include <linux/bug.h>
3038e353	22	#include <linux/errno.h>
77c9a5da SR	23	#include <linux/firewire.h>
77c9a5da SR	24	#include <linux/firewire-constants.h>
e8ca9702 SR	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>
e8ca9702	31
60063497	32	#include <linux/atomic.h>
cb7c96da	33	#include <asm/byteorder.h>
e8ca9702	34
77c9a5da	35	#include "core.h"
3038e353	36
a77754a7 KH	37	#define SELF_ID_PHY_ID(q) (((q) >> 24) & 0x3f)
	38	#define SELF_ID_EXTENDED(q) (((q) >> 23) & 0x01)
	39	#define SELF_ID_LINK_ON(q) (((q) >> 22) & 0x01)
	40	#define SELF_ID_GAP_COUNT(q) (((q) >> 16) & 0x3f)
	41	#define SELF_ID_PHY_SPEED(q) (((q) >> 14) & 0x03)
	42	#define SELF_ID_CONTENDER(q) (((q) >> 11) & 0x01)
	43	#define SELF_ID_PHY_INITIATOR(q) (((q) >> 1) & 0x01)
	44	#define SELF_ID_MORE_PACKETS(q) (((q) >> 0) & 0x01)
3038e353	45
a77754a7	46	#define SELF_ID_EXT_SEQUENCE(q) (((q) >> 20) & 0x07)
3038e353	47
77c9a5da SR	48	#define SELFID_PORT_CHILD 0x3
	49	#define SELFID_PORT_PARENT 0x2
	50	#define SELFID_PORT_NCONN 0x1
	51	#define SELFID_PORT_NONE 0x0
	52
3038e353 KH	53	static u32 count_ports(u32 sid, int total_port_count, int child_port_count)
	54	{
	55	u32 q;
	56	int port_type, shift, seq;
	57
	58	*total_port_count = 0;
	59	*child_port_count = 0;
	60
	61	shift = 6;
	62	q = *sid;
	63	seq = 0;
	64
	65	while (1) {
	66	port_type = (q >> shift) & 0x03;
	67	switch (port_type) {
	68	case SELFID_PORT_CHILD:
	69	(*child_port_count)++;
	70	case SELFID_PORT_PARENT:
	71	case SELFID_PORT_NCONN:
	72	(*total_port_count)++;
	73	case SELFID_PORT_NONE:
	74	break;
	75	}
	76
	77	shift -= 2;
	78	if (shift == 0) {
a77754a7	79	if (!SELF_ID_MORE_PACKETS(q))
3038e353 KH	80	return sid + 1;
	81
	82	shift = 16;
	83	sid++;
	84	q = *sid;
	85
c781c06d KH	86	/*
c781c06d KH	87	* Check that the extra packets actually are
3038e353 KH	88	* extended self ID packets and that the
3038e353 KH	89	* sequence numbers in the extended self ID
c781c06d KH	90	* packets increase as expected.
c781c06d KH	91	*/
3038e353	92
a77754a7 KH	93	if (!SELF_ID_EXTENDED(q) \|\|
a77754a7 KH	94	seq != SELF_ID_EXT_SEQUENCE(q))
3038e353 KH	95	return NULL;
	96
	97	seq++;
	98	}
	99	}
	100	}
	101
	102	static int get_port_type(u32 *sid, int port_index)
	103	{
	104	int index, shift;
	105
	106	index = (port_index + 5) / 8;
	107	shift = 16 - ((port_index + 5) & 7) * 2;
	108	return (sid[index] >> shift) & 0x03;
	109	}
	110
95688e97	111	static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
3038e353 KH	112	{
	113	struct fw_node *node;
	114
acafe7e3	115	node = kzalloc(struct_size(node, ports, port_count), GFP_ATOMIC);
3038e353 KH	116	if (node == NULL)
	117	return NULL;
	118
	119	node->color = color;
a77754a7 KH	120	node->node_id = LOCAL_BUS \| SELF_ID_PHY_ID(sid);
	121	node->link_on = SELF_ID_LINK_ON(sid);
	122	node->phy_speed = SELF_ID_PHY_SPEED(sid);
c9755e14	123	node->initiated_reset = SELF_ID_PHY_INITIATOR(sid);
3038e353 KH	124	node->port_count = port_count;
3038e353 KH	125
392910cf	126	refcount_set(&node->ref_count, 1);
3038e353 KH	127	INIT_LIST_HEAD(&node->link);
	128
	129	return node;
	130	}
	131
c781c06d KH	132	/*
c781c06d KH	133	* Compute the maximum hop count for this node and it's children. The
83db801c KH	134	* maximum hop count is the maximum number of connections between any
	135	* two nodes in the subtree rooted at this node. We need this for
	136	* setting the gap count. As we build the tree bottom up in
	137	* build_tree() below, this is fairly easy to do: for each node we
	138	* maintain the max hop count and the max depth, ie the number of hops
	139	* to the furthest leaf. Computing the max hop count breaks down into
	140	* two cases: either the path goes through this node, in which case
	141	* the hop count is the sum of the two biggest child depths plus 2.
	142	* Or it could be the case that the max hop path is entirely
	143	* containted in a child tree, in which case the max hop count is just
	144	* the max hop count of this child.
	145	*/
	146	static void update_hop_count(struct fw_node *node)
	147	{
	148	int depths[2] = { -1, -1 };
	149	int max_child_hops = 0;
	150	int i;
	151
	152	for (i = 0; i < node->port_count; i++) {
dae1a3aa	153	if (node->ports[i] == NULL)
83db801c KH	154	continue;
83db801c KH	155
dae1a3aa SR	156	if (node->ports[i]->max_hops > max_child_hops)
dae1a3aa SR	157	max_child_hops = node->ports[i]->max_hops;
83db801c	158
dae1a3aa	159	if (node->ports[i]->max_depth > depths[0]) {
83db801c	160	depths[1] = depths[0];
dae1a3aa SR	161	depths[0] = node->ports[i]->max_depth;
	162	} else if (node->ports[i]->max_depth > depths[1])
	163	depths[1] = node->ports[i]->max_depth;
83db801c KH	164	}
	165
	166	node->max_depth = depths[0] + 1;
	167	node->max_hops = max(max_child_hops, depths[0] + depths[1] + 2);
	168	}
	169
e5f84f82 SR	170	static inline struct fw_node fw_node(struct list_head l)
	171	{
	172	return list_entry(l, struct fw_node, link);
	173	}
83db801c	174
656b7afd	175	/*
3038e353 KH	176	* This function builds the tree representation of the topology given
	177	* by the self IDs from the latest bus reset. During the construction
	178	* of the tree, the function checks that the self IDs are valid and
af901ca1	179	* internally consistent. On success this function returns the
3038e353 KH	180	* fw_node corresponding to the local card otherwise NULL.
3038e353 KH	181	*/
473d28c7 KH	182	static struct fw_node build_tree(struct fw_card card,
473d28c7 KH	183	u32 *sid, int self_id_count)
3038e353	184	{
93e4fd45	185	struct fw_node node, child, local_node, irm_node;
3038e353	186	struct list_head stack, *h;
473d28c7	187	u32 next_sid, end, q;
3038e353	188	int i, port_count, child_port_count, phy_id, parent_count, stack_depth;
24d40125 SR	189	int gap_count;
24d40125 SR	190	bool beta_repeaters_present;
3038e353 KH	191
	192	local_node = NULL;
	193	node = NULL;
	194	INIT_LIST_HEAD(&stack);
	195	stack_depth = 0;
473d28c7	196	end = sid + self_id_count;
3038e353	197	phy_id = 0;
93e4fd45	198	irm_node = NULL;
a77754a7	199	gap_count = SELF_ID_GAP_COUNT(*sid);
24d40125	200	beta_repeaters_present = false;
3038e353 KH	201
	202	while (sid < end) {
	203	next_sid = count_ports(sid, &port_count, &child_port_count);
	204
	205	if (next_sid == NULL) {
26b4950d	206	fw_err(card, "inconsistent extended self IDs\n");
3038e353 KH	207	return NULL;
	208	}
	209
	210	q = *sid;
a77754a7	211	if (phy_id != SELF_ID_PHY_ID(q)) {
26b4950d SR	212	fw_err(card, "PHY ID mismatch in self ID: %d != %d\n",
26b4950d SR	213	phy_id, SELF_ID_PHY_ID(q));
3038e353 KH	214	return NULL;
	215	}
	216
	217	if (child_port_count > stack_depth) {
26b4950d	218	fw_err(card, "topology stack underflow\n");
3038e353 KH	219	return NULL;
	220	}
	221
c781c06d KH	222	/*
	223	* Seek back from the top of our stack to find the
	224	* start of the child nodes for this node.
	225	*/
3038e353 KH	226	for (i = 0, h = &stack; i < child_port_count; i++)
3038e353 KH	227	h = h->prev;
c1b91ce4 YD	228	/*
	229	* When the stack is empty, this yields an invalid value,
	230	* but that pointer will never be dereferenced.
	231	*/
3038e353 KH	232	child = fw_node(h);
	233
	234	node = fw_node_create(q, port_count, card->color);
	235	if (node == NULL) {
26b4950d	236	fw_err(card, "out of memory while building topology\n");
3038e353 KH	237	return NULL;
	238	}
	239
	240	if (phy_id == (card->node_id & 0x3f))
	241	local_node = node;
	242
a77754a7	243	if (SELF_ID_CONTENDER(q))
93e4fd45	244	irm_node = node;
3038e353 KH	245
	246	parent_count = 0;
	247
	248	for (i = 0; i < port_count; i++) {
	249	switch (get_port_type(sid, i)) {
	250	case SELFID_PORT_PARENT:
c781c06d KH	251	/*
c781c06d KH	252	* Who's your daddy? We dont know the
3038e353 KH	253	* parent node at this time, so we
	254	* temporarily abuse node->color for
	255	* remembering the entry in the
	256	* node->ports array where the parent
	257	* node should be. Later, when we
	258	* handle the parent node, we fix up
	259	* the reference.
	260	*/
	261	parent_count++;
	262	node->color = i;
	263	break;
	264
	265	case SELFID_PORT_CHILD:
dae1a3aa	266	node->ports[i] = child;
c781c06d KH	267	/*
	268	* Fix up parent reference for this
	269	* child node.
	270	*/
dae1a3aa	271	child->ports[child->color] = node;
3038e353 KH	272	child->color = card->color;
	273	child = fw_node(child->link.next);
	274	break;
	275	}
	276	}
	277
c781c06d KH	278	/*
c781c06d KH	279	* Check that the node reports exactly one parent
3038e353	280	* port, except for the root, which of course should
c781c06d KH	281	* have no parents.
c781c06d KH	282	*/
3038e353 KH	283	if ((next_sid == end && parent_count != 0) \|\|
3038e353 KH	284	(next_sid < end && parent_count != 1)) {
26b4950d SR	285	fw_err(card, "parent port inconsistency for node %d: "
26b4950d SR	286	"parent_count=%d\n", phy_id, parent_count);
3038e353 KH	287	return NULL;
	288	}
	289
	290	/* Pop the child nodes off the stack and push the new node. */
	291	__list_del(h->prev, &stack);
	292	list_add_tail(&node->link, &stack);
	293	stack_depth += 1 - child_port_count;
	294
24d40125 SR	295	if (node->phy_speed == SCODE_BETA &&
	296	parent_count + child_port_count > 1)
	297	beta_repeaters_present = true;
	298
c781c06d	299	/*
25b1c3d8 SR	300	* If PHYs report different gap counts, set an invalid count
25b1c3d8 SR	301	* which will force a gap count reconfiguration and a reset.
c781c06d	302	*/
a77754a7	303	if (SELF_ID_GAP_COUNT(q) != gap_count)
25b1c3d8	304	gap_count = 0;
83db801c KH	305
	306	update_hop_count(node);
	307
3038e353 KH	308	sid = next_sid;
	309	phy_id++;
	310	}
	311
	312	card->root_node = node;
93e4fd45	313	card->irm_node = irm_node;
83db801c	314	card->gap_count = gap_count;
24d40125	315	card->beta_repeaters_present = beta_repeaters_present;
3038e353 KH	316
	317	return local_node;
	318	}
	319
a98e2719 KH	320	typedef void (fw_node_callback_t)(struct fw_card card,
	321	struct fw_node * node,
	322	struct fw_node * parent);
3038e353	323
53dca511 SR	324	static void for_each_fw_node(struct fw_card card, struct fw_node root,
53dca511 SR	325	fw_node_callback_t callback)
3038e353 KH	326	{
	327	struct list_head list;
	328	struct fw_node node, next, child, parent;
	329	int i;
	330
	331	INIT_LIST_HEAD(&list);
	332
	333	fw_node_get(root);
	334	list_add_tail(&root->link, &list);
	335	parent = NULL;
	336	list_for_each_entry(node, &list, link) {
	337	node->color = card->color;
	338
	339	for (i = 0; i < node->port_count; i++) {
dae1a3aa	340	child = node->ports[i];
3038e353 KH	341	if (!child)
	342	continue;
	343	if (child->color == card->color)
	344	parent = child;
	345	else {
	346	fw_node_get(child);
	347	list_add_tail(&child->link, &list);
	348	}
	349	}
	350
	351	callback(card, node, parent);
	352	}
	353
	354	list_for_each_entry_safe(node, next, &list, link)
	355	fw_node_put(node);
	356	}
	357
53dca511 SR	358	static void report_lost_node(struct fw_card *card,
53dca511 SR	359	struct fw_node node, struct fw_node parent)
3038e353 KH	360	{
	361	fw_node_event(card, node, FW_NODE_DESTROYED);
	362	fw_node_put(node);
d6f95a3d SR	363
	364	/* Topology has changed - reset bus manager retry counter */
	365	card->bm_retries = 0;
3038e353 KH	366	}
3038e353 KH	367
53dca511 SR	368	static void report_found_node(struct fw_card *card,
53dca511 SR	369	struct fw_node node, struct fw_node parent)
3038e353 KH	370	{
	371	int b_path = (node->phy_speed == SCODE_BETA);
	372
	373	if (parent != NULL) {
748086eb SR	374	/* min() macro doesn't work here with gcc 3.4 */
	375	node->max_speed = parent->max_speed < node->phy_speed ?
	376	parent->max_speed : node->phy_speed;
3038e353 KH	377	node->b_path = parent->b_path && b_path;
	378	} else {
	379	node->max_speed = node->phy_speed;
	380	node->b_path = b_path;
	381	}
	382
	383	fw_node_event(card, node, FW_NODE_CREATED);
d6f95a3d SR	384
	385	/* Topology has changed - reset bus manager retry counter */
	386	card->bm_retries = 0;
3038e353 KH	387	}
	388
	389	void fw_destroy_nodes(struct fw_card *card)
	390	{
	391	unsigned long flags;
	392
	393	spin_lock_irqsave(&card->lock, flags);
	394	card->color++;
	395	if (card->local_node != NULL)
	396	for_each_fw_node(card, card->local_node, report_lost_node);
15803478	397	card->local_node = NULL;
3038e353 KH	398	spin_unlock_irqrestore(&card->lock, flags);
	399	}
	400
	401	static void move_tree(struct fw_node node0, struct fw_node node1, int port)
	402	{
	403	struct fw_node *tree;
	404	int i;
	405
dae1a3aa SR	406	tree = node1->ports[port];
dae1a3aa SR	407	node0->ports[port] = tree;
3038e353	408	for (i = 0; i < tree->port_count; i++) {
dae1a3aa SR	409	if (tree->ports[i] == node1) {
dae1a3aa SR	410	tree->ports[i] = node0;
3038e353 KH	411	break;
	412	}
	413	}
	414	}
	415
656b7afd SR	416	/*
	417	* Compare the old topology tree for card with the new one specified by root.
	418	* Queue the nodes and mark them as either found, lost or updated.
	419	* Update the nodes in the card topology tree as we go.
3038e353	420	*/
53dca511	421	static void update_tree(struct fw_card card, struct fw_node root)
3038e353 KH	422	{
3038e353 KH	423	struct list_head list0, list1;
77e55719	424	struct fw_node node0, node1, *next1;
3038e353 KH	425	int i, event;
	426
	427	INIT_LIST_HEAD(&list0);
	428	list_add_tail(&card->local_node->link, &list0);
	429	INIT_LIST_HEAD(&list1);
	430	list_add_tail(&root->link, &list1);
	431
	432	node0 = fw_node(list0.next);
	433	node1 = fw_node(list1.next);
3038e353 KH	434
3038e353 KH	435	while (&node0->link != &list0) {
a2cdebe3	436	WARN_ON(node0->port_count != node1->port_count);
3038e353	437
3038e353 KH	438	if (node0->link_on && !node1->link_on)
	439	event = FW_NODE_LINK_OFF;
	440	else if (!node0->link_on && node1->link_on)
	441	event = FW_NODE_LINK_ON;
c9755e14 SR	442	else if (node1->initiated_reset && node1->link_on)
c9755e14 SR	443	event = FW_NODE_INITIATED_RESET;
3038e353 KH	444	else
	445	event = FW_NODE_UPDATED;
	446
	447	node0->node_id = node1->node_id;
	448	node0->color = card->color;
	449	node0->link_on = node1->link_on;
	450	node0->initiated_reset = node1->initiated_reset;
83db801c	451	node0->max_hops = node1->max_hops;
3038e353 KH	452	node1->color = card->color;
	453	fw_node_event(card, node0, event);
	454
	455	if (card->root_node == node1)
	456	card->root_node = node0;
	457	if (card->irm_node == node1)
	458	card->irm_node = node0;
	459
	460	for (i = 0; i < node0->port_count; i++) {
dae1a3aa	461	if (node0->ports[i] && node1->ports[i]) {
c781c06d KH	462	/*
c781c06d KH	463	* This port didn't change, queue the
3038e353	464	* connected node for further
c781c06d KH	465	* investigation.
c781c06d KH	466	*/
dae1a3aa	467	if (node0->ports[i]->color == card->color)
3038e353	468	continue;
dae1a3aa SR	469	list_add_tail(&node0->ports[i]->link, &list0);
	470	list_add_tail(&node1->ports[i]->link, &list1);
	471	} else if (node0->ports[i]) {
c781c06d KH	472	/*
c781c06d KH	473	* The nodes connected here were
3038e353 KH	474	* unplugged; unref the lost nodes and
3038e353 KH	475	* queue FW_NODE_LOST callbacks for
c781c06d KH	476	* them.
c781c06d KH	477	*/
3038e353	478
dae1a3aa	479	for_each_fw_node(card, node0->ports[i],
3038e353	480	report_lost_node);
dae1a3aa SR	481	node0->ports[i] = NULL;
dae1a3aa SR	482	} else if (node1->ports[i]) {
c781c06d KH	483	/*
c781c06d KH	484	* One or more node were connected to
3038e353 KH	485	* this port. Move the new nodes into
3038e353 KH	486	* the tree and queue FW_NODE_CREATED
c781c06d KH	487	* callbacks for them.
c781c06d KH	488	*/
3038e353	489	move_tree(node0, node1, i);
dae1a3aa	490	for_each_fw_node(card, node0->ports[i],
3038e353	491	report_found_node);
3038e353 KH	492	}
	493	}
	494
	495	node0 = fw_node(node0->link.next);
77e55719 JF	496	next1 = fw_node(node1->link.next);
	497	fw_node_put(node1);
	498	node1 = next1;
3038e353 KH	499	}
	500	}
	501
53dca511 SR	502	static void update_topology_map(struct fw_card *card,
53dca511 SR	503	u32 *self_ids, int self_id_count)
473d28c7	504	{
cb7c96da SR	505	int node_count = (card->root_node->node_id & 0x3f) + 1;
	506	__be32 *map = card->topology_map;
	507
	508	*map++ = cpu_to_be32((self_id_count + 2) << 16);
	509	*map++ = cpu_to_be32(be32_to_cpu(card->topology_map[1]) + 1);
	510	*map++ = cpu_to_be32((node_count << 16) \| self_id_count);
	511
	512	while (self_id_count--)
	513	*map++ = cpu_to_be32p(self_ids++);
473d28c7	514
e175569c	515	fw_compute_block_crc(card->topology_map);
473d28c7 KH	516	}
473d28c7 KH	517
53dca511	518	void fw_core_handle_bus_reset(struct fw_card *card, int node_id, int generation,
c8a94ded	519	int self_id_count, u32 *self_ids, bool bm_abdicate)
3038e353 KH	520	{
	521	struct fw_node *local_node;
	522	unsigned long flags;
3038e353	523
a5c7f471 SR	524	/*
	525	* If the selfID buffer is not the immediate successor of the
	526	* previously processed one, we cannot reliably compare the
	527	* old and new topologies.
	528	*/
8cd0bbbd	529	if (!is_next_generation(generation, card->generation) &&
a5c7f471	530	card->local_node != NULL) {
a5c7f471 SR	531	fw_destroy_nodes(card);
	532	card->bm_retries = 0;
	533	}
	534
3038e353 KH	535	spin_lock_irqsave(&card->lock, flags);
3038e353 KH	536
db3c9cc1	537	card->broadcast_channel_allocated = card->broadcast_channel_auto_allocated;
3038e353	538	card->node_id = node_id;
b5d2a5e0 SR	539	/*
	540	* Update node_id before generation to prevent anybody from using
	541	* a stale node_id together with a current generation.
	542	*/
	543	smp_wmb();
3038e353	544	card->generation = generation;
e71084af	545	card->reset_jiffies = get_jiffies_64();
250b2b6d	546	card->bm_node_id = 0xffff;
c8a94ded	547	card->bm_abdicate = bm_abdicate;
0fa1986f	548	fw_schedule_bm_work(card, 0);
3038e353	549
473d28c7 KH	550	local_node = build_tree(card, self_ids, self_id_count);
	551
	552	update_topology_map(card, self_ids, self_id_count);
3038e353 KH	553
	554	card->color++;
	555
	556	if (local_node == NULL) {
26b4950d	557	fw_err(card, "topology build failed\n");
3038e353 KH	558	/* FIXME: We need to issue a bus reset in this case. */
	559	} else if (card->local_node == NULL) {
	560	card->local_node = local_node;
	561	for_each_fw_node(card, local_node, report_found_node);
	562	} else {
83db801c	563	update_tree(card, local_node);
3038e353 KH	564	}
	565
	566	spin_unlock_irqrestore(&card->lock, flags);
	567	}
3038e353	568	EXPORT_SYMBOL(fw_core_handle_bus_reset);