/*
 * Node information (ConfigROM) collection and management.
 *
 * Copyright (C) 2000		Andreas E. Bombe
 *               2001-2003	Ben Collins <bcollins@debian.net>
 *
 * This code is licensed under the GPL.  See the file COPYING in the root
 * directory of the kernel sources for details.
 */

#include <linux/kernel.h>
#include <linux/config.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <linux/kmod.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <asm/atomic.h>

#include "ieee1394_types.h"
#include "ieee1394.h"
#include "hosts.h"
#include "ieee1394_transactions.h"
#include "highlevel.h"
#include "csr.h"
#include "nodemgr.h"



static char *nodemgr_find_oui_name(int oui)
{
#ifdef CONFIG_IEEE1394_OUI_DB
	extern struct oui_list_struct {
		int oui;
		char *name;
	} oui_list[];
	int i;

	for (i = 0; oui_list[i].name; i++)
		if (oui_list[i].oui == oui)
			return oui_list[i].name;
#endif
	return NULL;
}


/* 
 * Basically what we do here is start off retrieving the bus_info block.
 * From there will fill in some info about the node, verify it is of IEEE
 * 1394 type, and that the crc checks out ok. After that we start off with
 * the root directory, and subdirectories. To do this, we retrieve the
 * quadlet header for a directory, find out the length, and retrieve the
 * complete directory entry (be it a leaf or a directory). We then process
 * it and add the info to our structure for that particular node.
 *
 * We verify CRC's along the way for each directory/block/leaf. The entire
 * node structure is generic, and simply stores the information in a way
 * that's easy to parse by the protocol interface.
 */

/* 
 * The nodemgr relies heavily on the Driver Model for device callbacks and
 * driver/device mappings. The old nodemgr used to handle all this itself,
 * but now we are much simpler because of the LDM.
 */

static DECLARE_MUTEX(nodemgr_serialize);


struct host_info {
	struct hpsb_host *host;
	struct list_head list;
	struct completion exited;
	struct semaphore reset_sem;
	int pid;
	char daemon_name[15];
};

static struct hpsb_highlevel nodemgr_highlevel;

static int nodemgr_driverdata_ne;
static int nodemgr_driverdata_host;

static struct device_driver nodemgr_driver_ne = {
	.name	= "ieee1394_node",
	.bus	= &ieee1394_bus_type,
};

static struct device_driver nodemgr_driver_host = {
	.name	= "ieee1394_host",
	.bus	= &ieee1394_bus_type,
};


#define fw_attr(class, class_type, field, type, format_string)		\
static ssize_t fw_show_##class##_##field (struct device *dev, char *buf)\
{									\
	class_type *class;						\
	class = container_of(dev, class_type, device);			\
	return sprintf(buf, format_string, (type)class->field);		\
}									\
static struct device_attribute dev_attr_##class##_##field = {		\
	.attr = {.name = __stringify(field), .mode = S_IRUGO },		\
	.show   = fw_show_##class##_##field,				\
};


#define fw_drv_attr(field, type, format_string)			\
static ssize_t fw_drv_show_##field (struct device_driver *drv, char *buf) \
{								\
	struct hpsb_protocol_driver *driver;			\
	driver = container_of(drv, struct hpsb_protocol_driver, driver); \
	return sprintf(buf, format_string, (type)driver->field);\
}								\
static struct driver_attribute driver_attr_drv_##field = {	\
        .attr = {.name = __stringify(field), .mode = S_IRUGO },	\
        .show   = fw_drv_show_##field,				\
};


static ssize_t fw_show_ne_bus_options(struct device *dev, char *buf)
{
	struct node_entry *ne = container_of(dev, struct node_entry, device);

	return sprintf(buf, "IRMC(%d) CMC(%d) ISC(%d) BMC(%d) PMC(%d) GEN(%d) "
			"LSPD(%d) MAX_REC(%d) CYC_CLK_ACC(%d)\n", ne->busopt.irmc,
			ne->busopt.cmc, ne->busopt.isc, ne->busopt.bmc,
			ne->busopt.pmc, ne->busopt.generation, ne->busopt.lnkspd,
			ne->busopt.max_rec, ne->busopt.cyc_clk_acc);
}
static DEVICE_ATTR(bus_options,S_IRUGO,fw_show_ne_bus_options,NULL);


static ssize_t fw_show_ne_tlabels_free(struct device *dev, char *buf)
{
	struct node_entry *ne = container_of(dev, struct node_entry, device);
	return sprintf(buf, "%d\n", atomic_read(&ne->tpool->count.count) + 1);
}
static DEVICE_ATTR(tlabels_free,S_IRUGO,fw_show_ne_tlabels_free,NULL);


static ssize_t fw_show_ne_tlabels_allocations(struct device *dev, char *buf)
{
	struct node_entry *ne = container_of(dev, struct node_entry, device);
	return sprintf(buf, "%u\n", ne->tpool->allocations);
}
static DEVICE_ATTR(tlabels_allocations,S_IRUGO,fw_show_ne_tlabels_allocations,NULL);


static ssize_t fw_show_ne_tlabels_mask(struct device *dev, char *buf)
{
	struct node_entry *ne = container_of(dev, struct node_entry, device);
#if (BITS_PER_LONG <= 32)
	return sprintf(buf, "0x%08lx%08lx\n", ne->tpool->pool[0], ne->tpool->pool[1]);
#else
	return sprintf(buf, "0x%016lx\n", ne->tpool->pool[0]);
#endif
}
static DEVICE_ATTR(tlabels_mask,S_IRUGO,fw_show_ne_tlabels_mask,NULL);


fw_attr(ne, struct node_entry, capabilities, unsigned int, "0x%06x\n")
fw_attr(ne, struct node_entry, nodeid, unsigned int, "0x%04x\n")

fw_attr(ne, struct node_entry, vendor_id, unsigned int, "0x%06x\n")
fw_attr(ne, struct node_entry, vendor_name, const char *, "%s\n")
fw_attr(ne, struct node_entry, vendor_oui, const char *, "%s\n")

fw_attr(ne, struct node_entry, guid, unsigned long long, "0x%016Lx\n")
fw_attr(ne, struct node_entry, guid_vendor_id, unsigned int, "0x%06x\n")
fw_attr(ne, struct node_entry, guid_vendor_oui, const char *, "%s\n")

static struct device_attribute *const fw_ne_attrs[] = {
	&dev_attr_ne_guid,
	&dev_attr_ne_guid_vendor_id,
	&dev_attr_ne_capabilities,
	&dev_attr_ne_vendor_id,
	&dev_attr_ne_nodeid,
	&dev_attr_bus_options,
	&dev_attr_tlabels_free,
	&dev_attr_tlabels_allocations,
	&dev_attr_tlabels_mask,
};



fw_attr(ud, struct unit_directory, address, unsigned long long, "0x%016Lx\n")
fw_attr(ud, struct unit_directory, length, int, "%d\n")
/* These are all dependent on the value being provided */
fw_attr(ud, struct unit_directory, vendor_id, unsigned int, "0x%06x\n")
fw_attr(ud, struct unit_directory, model_id, unsigned int, "0x%06x\n")
fw_attr(ud, struct unit_directory, specifier_id, unsigned int, "0x%06x\n")
fw_attr(ud, struct unit_directory, version, unsigned int, "0x%06x\n")
fw_attr(ud, struct unit_directory, vendor_name, const char *, "%s\n")
fw_attr(ud, struct unit_directory, vendor_oui, const char *, "%s\n")
fw_attr(ud, struct unit_directory, model_name, const char *, "%s\n")

static struct device_attribute *const fw_ud_attrs[] = {
	&dev_attr_ud_address,
	&dev_attr_ud_length,
};


fw_attr(host, struct hpsb_host, node_count, int, "%d\n")
fw_attr(host, struct hpsb_host, selfid_count, int, "%d\n")
fw_attr(host, struct hpsb_host, nodes_active, int, "%d\n")
fw_attr(host, struct hpsb_host, in_bus_reset, int, "%d\n")
fw_attr(host, struct hpsb_host, is_root, int, "%d\n")
fw_attr(host, struct hpsb_host, is_cycmst, int, "%d\n")
fw_attr(host, struct hpsb_host, is_irm, int, "%d\n")
fw_attr(host, struct hpsb_host, is_busmgr, int, "%d\n")

static struct device_attribute *const fw_host_attrs[] = {
	&dev_attr_host_node_count,
	&dev_attr_host_selfid_count,
	&dev_attr_host_nodes_active,
	&dev_attr_host_in_bus_reset,
	&dev_attr_host_is_root,
	&dev_attr_host_is_cycmst,
	&dev_attr_host_is_irm,
	&dev_attr_host_is_busmgr,
};


static ssize_t fw_show_drv_device_ids(struct device_driver *drv, char *buf)
{
	struct hpsb_protocol_driver *driver;
	struct ieee1394_device_id *id;
	int length = 0;
	char *scratch = buf;

        driver = container_of(drv, struct hpsb_protocol_driver, driver);

	for (id = driver->id_table; id->match_flags != 0; id++) {
		int need_coma = 0;

		if (id->match_flags & IEEE1394_MATCH_VENDOR_ID) {
			length += sprintf(scratch, "vendor_id=0x%06x", id->vendor_id);
			scratch = buf + length;
			need_coma++;
		}

		if (id->match_flags & IEEE1394_MATCH_MODEL_ID) {
			length += sprintf(scratch, "%smodel_id=0x%06x",
					  need_coma++ ? "," : "",
					  id->model_id);
			scratch = buf + length;
		}

		if (id->match_flags & IEEE1394_MATCH_SPECIFIER_ID) {
			length += sprintf(scratch, "%sspecifier_id=0x%06x",
					  need_coma++ ? "," : "",
					  id->specifier_id);
			scratch = buf + length;
		}

		if (id->match_flags & IEEE1394_MATCH_VERSION) {
			length += sprintf(scratch, "%sversion=0x%06x",
					  need_coma++ ? "," : "",
					  id->version);
			scratch = buf + length;
		}

		if (need_coma) {
			*scratch++ = '\n';
			length++;
		}
	}

	return length;
}
static DRIVER_ATTR(device_ids,S_IRUGO,fw_show_drv_device_ids,NULL);


fw_drv_attr(name, const char *, "%s\n")

static struct driver_attribute *const fw_drv_attrs[] = {
	&driver_attr_drv_name,
	&driver_attr_device_ids,
};


static void nodemgr_create_drv_files(struct hpsb_protocol_driver *driver)
{
	struct device_driver *drv = &driver->driver;
	int i;

	for (i = 0; i < ARRAY_SIZE(fw_drv_attrs); i++)
		driver_create_file(drv, fw_drv_attrs[i]);
}


static void nodemgr_remove_drv_files(struct hpsb_protocol_driver *driver)
{
	struct device_driver *drv = &driver->driver;
	int i;

	for (i = 0; i < ARRAY_SIZE(fw_drv_attrs); i++)
		driver_remove_file(drv, fw_drv_attrs[i]);
}


static void nodemgr_create_ne_dev_files(struct node_entry *ne)
{
	struct device *dev = &ne->device;
	int i;

	for (i = 0; i < ARRAY_SIZE(fw_ne_attrs); i++)
		device_create_file(dev, fw_ne_attrs[i]);
}


static void nodemgr_create_host_dev_files(struct hpsb_host *host)
{
	struct device *dev = &host->device;
	int i;

	for (i = 0; i < ARRAY_SIZE(fw_host_attrs); i++)
		device_create_file(dev, fw_host_attrs[i]);
}


static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t nodeid);

static void nodemgr_update_host_dev_links(struct hpsb_host *host)
{
	struct device *dev = &host->device;
	struct node_entry *ne;

	sysfs_remove_link(&dev->kobj, "irm_id");
	sysfs_remove_link(&dev->kobj, "busmgr_id");
	sysfs_remove_link(&dev->kobj, "host_id");

	if ((ne = find_entry_by_nodeid(host, host->irm_id)))
		sysfs_create_link(&dev->kobj, &ne->device.kobj, "irm_id");
	if ((ne = find_entry_by_nodeid(host, host->busmgr_id)))
		sysfs_create_link(&dev->kobj, &ne->device.kobj, "busmgr_id");
	if ((ne = find_entry_by_nodeid(host, host->node_id)))
		sysfs_create_link(&dev->kobj, &ne->device.kobj, "host_id");
}

static void nodemgr_create_ud_dev_files(struct unit_directory *ud)
{
	struct device *dev = &ud->device;
	int i;

	for (i = 0; i < ARRAY_SIZE(fw_ud_attrs); i++)
		device_create_file(dev, fw_ud_attrs[i]);

	if (ud->flags & UNIT_DIRECTORY_SPECIFIER_ID)
		device_create_file(dev, &dev_attr_ud_specifier_id);

	if (ud->flags & UNIT_DIRECTORY_VERSION)
		device_create_file(dev, &dev_attr_ud_version);

	if (ud->flags & UNIT_DIRECTORY_VENDOR_ID) {
		device_create_file(dev, &dev_attr_ud_vendor_id);
		if (ud->flags & UNIT_DIRECTORY_VENDOR_TEXT)
			device_create_file(dev, &dev_attr_ud_vendor_name);
	}

	if (ud->flags & UNIT_DIRECTORY_MODEL_ID) {
		device_create_file(dev, &dev_attr_ud_model_id);
		if (ud->flags & UNIT_DIRECTORY_MODEL_TEXT)
			device_create_file(dev, &dev_attr_ud_model_name);
	}
}


static int nodemgr_bus_match(struct device * dev, struct device_driver * drv)
{
        struct hpsb_protocol_driver *driver;
        struct unit_directory *ud;
	struct ieee1394_device_id *id;

	if (dev->driver_data == &nodemgr_driverdata_ne ||
	    dev->driver_data == &nodemgr_driverdata_host ||
	    drv == &nodemgr_driver_ne || drv == &nodemgr_driver_host)
		return 0;

	ud = container_of(dev, struct unit_directory, device);
	driver = container_of(drv, struct hpsb_protocol_driver, driver);

        for (id = driver->id_table; id->match_flags != 0; id++) {
                if ((id->match_flags & IEEE1394_MATCH_VENDOR_ID) &&
                    id->vendor_id != ud->vendor_id)
                        continue;

                if ((id->match_flags & IEEE1394_MATCH_MODEL_ID) &&
                    id->model_id != ud->model_id)
                        continue;

                if ((id->match_flags & IEEE1394_MATCH_SPECIFIER_ID) &&
                    id->specifier_id != ud->specifier_id)
                        continue;

                if ((id->match_flags & IEEE1394_MATCH_VERSION) &&
                    id->version != ud->version)
                        continue;

		return 1;
        }

	return 0;
}


static void nodemgr_release_ud(struct device *dev)
{
	kfree(container_of(dev, struct unit_directory, device));
}


static void nodemgr_release_ne(struct device *dev)
{
	kfree(container_of(dev, struct node_entry, device));
}


static void nodemgr_remove_ud(struct unit_directory *ud)
{
	struct device *dev = &ud->device;
	struct list_head *lh, *next;
	int i;

	list_for_each_safe(lh, next, &ud->device.children) {
		struct unit_directory *ud;
		ud = container_of(list_to_dev(lh), struct unit_directory, device);
		nodemgr_remove_ud(ud);
	}

	for (i = 0; i < ARRAY_SIZE(fw_ud_attrs); i++)
		device_remove_file(dev, fw_ud_attrs[i]);

	device_remove_file(dev, &dev_attr_ud_specifier_id);
	device_remove_file(dev, &dev_attr_ud_version);
	device_remove_file(dev, &dev_attr_ud_vendor_id);
	device_remove_file(dev, &dev_attr_ud_vendor_name);
	device_remove_file(dev, &dev_attr_ud_vendor_oui);
	device_remove_file(dev, &dev_attr_ud_model_id);
	device_remove_file(dev, &dev_attr_ud_model_name);

	device_unregister(dev);
}


static void nodemgr_remove_node_uds(struct node_entry *ne)
{
	struct list_head *lh, *next;

	list_for_each_safe(lh, next, &ne->device.children) {
		struct unit_directory *ud;
		ud = container_of(list_to_dev(lh), struct unit_directory, device);
		nodemgr_remove_ud(ud);
	}
}


static void nodemgr_remove_ne(struct node_entry *ne)
{
	struct device *dev = &ne->device;
	int i;

	nodemgr_remove_node_uds(ne);

	for (i = 0; i < ARRAY_SIZE(fw_ne_attrs); i++)
		device_remove_file(dev, fw_ne_attrs[i]);

	device_remove_file(dev, &dev_attr_ne_guid_vendor_oui);
	device_remove_file(dev, &dev_attr_ne_vendor_name);
	device_remove_file(dev, &dev_attr_ne_vendor_oui);

	device_unregister(dev);
}


static void nodemgr_remove_host_dev(struct device *dev)
{
	int i;
	struct list_head *lh, *next;

	list_for_each_safe(lh, next, &dev->children) {
		struct node_entry *ne;
		ne = container_of(list_to_dev(lh), struct node_entry, device);
		nodemgr_remove_ne(ne);
	}

	for (i = 0; i < ARRAY_SIZE(fw_host_attrs); i++)
		device_remove_file(dev, fw_host_attrs[i]);

	sysfs_remove_link(&dev->kobj, "irm_id");
	sysfs_remove_link(&dev->kobj, "busmgr_id");
	sysfs_remove_link(&dev->kobj, "host_id");
}


static struct device nodemgr_dev_template_ud = {
	.bus		= &ieee1394_bus_type,
	.release	= nodemgr_release_ud,
};


static struct device nodemgr_dev_template_ne = {
	.bus		= &ieee1394_bus_type,
	.release	= nodemgr_release_ne,
	.driver		= &nodemgr_driver_ne,
	.driver_data	= &nodemgr_driverdata_ne,
};


static struct device nodemgr_dev_template_host = {
	.bus		= &ieee1394_bus_type,
	.driver		= &nodemgr_driver_host,
	.driver_data	= &nodemgr_driverdata_host,
};


static int nodemgr_hotplug(struct device *dev, char **envp, int num_envp,
                           char *buffer, int buffer_size);


struct bus_type ieee1394_bus_type = {
	.name		= "ieee1394",
	.match		= nodemgr_bus_match,
	.hotplug	= nodemgr_hotplug,
};


static int nodemgr_read_quadlet(struct hpsb_host *host,
				nodeid_t nodeid, unsigned int generation,
				octlet_t address, quadlet_t *quad)
{
	int i;
	int ret = 0;

	for (i = 0; i < 3; i++) {
		ret = hpsb_read(host, nodeid, generation, address, quad, 4);
		if (!ret)
			break;

		set_current_state(TASK_INTERRUPTIBLE);
		if (schedule_timeout (HZ/3))
			return -1;
	}
	*quad = be32_to_cpu(*quad);

	return ret;
}

static int nodemgr_size_text_leaf(struct hpsb_host *host,
				  nodeid_t nodeid, unsigned int generation,
				  octlet_t address)
{
	quadlet_t quad;
	int size = 0;

	if (nodemgr_read_quadlet(host, nodeid, generation, address, &quad))
		return -1;

	if (CONFIG_ROM_KEY(quad) == CONFIG_ROM_DESCRIPTOR_LEAF) {
		/* This is the offset.  */
		address += 4 * CONFIG_ROM_VALUE(quad); 
		if (nodemgr_read_quadlet(host, nodeid, generation, address, &quad))
			return -1;
		/* Now we got the size of the text descriptor leaf. */
		size = CONFIG_ROM_LEAF_LENGTH(quad);
	}

	return size;
}

static int nodemgr_read_text_leaf(struct node_entry *ne,
				  octlet_t address,
				  quadlet_t *quadp)
{
	quadlet_t quad;
	int i, size, ret;

	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation, address, &quad)
	    || CONFIG_ROM_KEY(quad) != CONFIG_ROM_DESCRIPTOR_LEAF)
		return -1;

	/* This is the offset.  */
	address += 4 * CONFIG_ROM_VALUE(quad);
	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation, address, &quad))
		return -1;

	/* Now we got the size of the text descriptor leaf. */
	size = CONFIG_ROM_LEAF_LENGTH(quad) - 2;
	if (size <= 0)
		return -1;

	address += 4;
	for (i = 0; i < 2; i++, address += 4, quadp++) {
		if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation, address, quadp))
			return -1;
	}

	/* Now read the text string.  */
	ret = -ENXIO;
	for (; size > 0; size--, address += 4, quadp++) {
		for (i = 0; i < 3; i++) {
			ret = hpsb_node_read(ne, address, quadp, 4);
			if (ret != -EAGAIN)
				break;
		}
		if (ret)
			break;
	}

	return ret;
}

static struct node_entry *nodemgr_scan_root_directory
	(struct hpsb_host *host, nodeid_t nodeid, unsigned int generation)
{
	octlet_t address;
	quadlet_t quad;
	int length;
	int code, size, total_size;
	struct node_entry *ne;

	address = CSR_REGISTER_BASE + CSR_CONFIG_ROM;
	
	if (nodemgr_read_quadlet(host, nodeid, generation, address, &quad))
		return NULL;

	if (CONFIG_ROM_BUS_INFO_LENGTH(quad) == 1)  /* minimal config rom */
		return NULL;

	address += 4 + CONFIG_ROM_BUS_INFO_LENGTH(quad) * 4;

	if (nodemgr_read_quadlet(host, nodeid, generation, address, &quad))
		return NULL;
	length = CONFIG_ROM_ROOT_LENGTH(quad);
	address += 4;

	size = 0;
	total_size = sizeof(struct node_entry);
	for (; length > 0; length--, address += 4) {
		if (nodemgr_read_quadlet(host, nodeid, generation, address, &quad))
			return NULL;
		code = CONFIG_ROM_KEY(quad);

		if (code == CONFIG_ROM_VENDOR_ID && length > 0) {
			/* Check if there is a text descriptor leaf
			   immediately after this.  */
			size = nodemgr_size_text_leaf(host, nodeid, generation,
						      address + 4);
			if (size > 0) {
				address += 4;
				length--;
				total_size += (size + 1) * sizeof (quadlet_t);
			} else if (size < 0)
				return NULL;
		}
	}
	ne = kmalloc(total_size, GFP_KERNEL);

	if (!ne)
		return NULL;

	memset(ne, 0, total_size);

	if (size != 0) {
		ne->vendor_name = (const char *) &(ne->quadlets[2]);
		ne->quadlets[size] = 0;
	} else {
		ne->vendor_name = NULL;
	}

	return ne; 
}


static void nodemgr_process_config_rom(struct host_info *hi,
		struct node_entry *ne, quadlet_t busoptions);

static struct node_entry *nodemgr_create_node(octlet_t guid, quadlet_t busoptions,
					      struct host_info *hi, nodeid_t nodeid,
					      unsigned int generation)
{
	struct hpsb_host *host = hi->host;
        struct node_entry *ne;

	ne = nodemgr_scan_root_directory (host, nodeid, generation);
        if (!ne) return NULL;

	ne->tpool = &host->tpool[nodeid & NODE_MASK];

        ne->host = host;
        ne->nodeid = nodeid;
	ne->generation = generation;

        ne->guid = guid;
	ne->guid_vendor_id = (guid >> 40) & 0xffffff;
	ne->guid_vendor_oui = nodemgr_find_oui_name(ne->guid_vendor_id);

	memcpy(&ne->device, &nodemgr_dev_template_ne,
	       sizeof(ne->device));
	ne->device.parent = &host->device;
	snprintf(ne->device.bus_id, BUS_ID_SIZE, "%016Lx",
		 (unsigned long long)(ne->guid));

	device_register(&ne->device);

	if (ne->guid_vendor_oui)
		device_create_file(&ne->device, &dev_attr_ne_guid_vendor_oui);
	nodemgr_create_ne_dev_files(ne);

	nodemgr_process_config_rom (hi, ne, busoptions);

	HPSB_DEBUG("%s added: ID:BUS[" NODE_BUS_FMT "]  GUID[%016Lx]",
		   (host->node_id == nodeid) ? "Host" : "Node",
		   NODE_BUS_ARGS(host, nodeid), (unsigned long long)guid);

        return ne;
}


struct guid_search_baton {
	u64 guid;
	struct node_entry *ne;
};

static int nodemgr_guid_search_cb(struct device *dev, void *__data)
{
        struct guid_search_baton *search = __data;
        struct node_entry *ne;

        if (dev->driver_data != &nodemgr_driverdata_ne)
                return 0;

        ne = container_of(dev, struct node_entry, device);

        if (ne->guid == search->guid) {
		search->ne = ne;
		return 1;
	}

	return 0;
}

static struct node_entry *find_entry_by_guid(u64 guid)
{
	struct guid_search_baton search;

	search.guid = guid;
	search.ne = NULL;

	bus_for_each_dev(&ieee1394_bus_type, NULL, &search, nodemgr_guid_search_cb);

        return search.ne;
}


struct nodeid_search_baton {
	nodeid_t nodeid;
	struct node_entry *ne;
	struct hpsb_host *host;
};

static int nodemgr_nodeid_search_cb(struct device *dev, void *__data)
{
	struct nodeid_search_baton *search = __data;
	struct node_entry *ne;

	if (dev->driver_data != &nodemgr_driverdata_ne)
		return 0;

	ne = container_of(dev, struct node_entry, device);

	if (ne->host == search->host && ne->nodeid == search->nodeid) {
		search->ne = ne;
		/* Returning 1 stops the iteration */
		return 1;
	}

	return 0;
}

static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t nodeid)
{
	struct nodeid_search_baton search;

	search.nodeid = nodeid;
	search.ne = NULL;
	search.host = host;

	bus_for_each_dev(&ieee1394_bus_type, NULL, &search, nodemgr_nodeid_search_cb);

	return search.ne;
}

static struct unit_directory *nodemgr_scan_unit_directory
	(struct node_entry *ne, octlet_t address)
{
	struct unit_directory *ud;
	quadlet_t quad;
	u8 flags, todo;
	int length, size, total_size, count;
	int vendor_name_size, model_name_size;

	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation, address, &quad))
		return NULL;
	length = CONFIG_ROM_DIRECTORY_LENGTH(quad) ;
	address += 4;

	size = 0;
	total_size = sizeof (struct unit_directory);
	flags = 0;
	count = 0;
	vendor_name_size = 0;
	model_name_size = 0;
	for (; length > 0; length--, address += 4) {
		int code;
		quadlet_t value;

		if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
					 address, &quad))
			return NULL;
		code = CONFIG_ROM_KEY(quad);
		value = CONFIG_ROM_VALUE(quad);

		todo = 0;
		switch (code) {
		case CONFIG_ROM_VENDOR_ID:
			todo = UNIT_DIRECTORY_VENDOR_TEXT;
			break;

		case CONFIG_ROM_MODEL_ID:
			todo = UNIT_DIRECTORY_MODEL_TEXT;
			break;

		case CONFIG_ROM_SPECIFIER_ID:
		case CONFIG_ROM_UNIT_SW_VERSION:
			break;

		case CONFIG_ROM_DESCRIPTOR_LEAF:
		case CONFIG_ROM_DESCRIPTOR_DIRECTORY:
			/* TODO: read strings... icons? */
			break;

		default:
			/* Which types of quadlets do we want to
			   store?  Only count immediate values and
			   CSR offsets for now.  */
			code &= CONFIG_ROM_KEY_TYPE_MASK;
			if ((code & CONFIG_ROM_KEY_TYPE_LEAF) == 0)
				count++;
			break;
		}

		if (todo && length > 0) {
			/* Check if there is a text descriptor leaf
			   immediately after this.  */
			size = nodemgr_size_text_leaf(ne->host,
						      ne->nodeid,
						      ne->generation,
						      address + 4);

			if (todo == UNIT_DIRECTORY_VENDOR_TEXT)
				vendor_name_size = size;
			else
				model_name_size = size;

			if (size > 0) {
				address += 4;
				length--;
				flags |= todo;
				total_size += (size + 1) * sizeof (quadlet_t);
			}
			else if (size < 0)
				return NULL;
		}
	}

	total_size += count * sizeof (quadlet_t);
	ud = kmalloc (total_size, GFP_KERNEL);

	if (ud != NULL) {
		memset (ud, 0, total_size);
		ud->flags = flags;
		ud->length = count;
		ud->vendor_name_size = vendor_name_size;
		ud->model_name_size = model_name_size;
	}

	return ud;
}


/* This implementation currently only scans the config rom and its
 * immediate unit directories looking for software_id and
 * software_version entries, in order to get driver autoloading working. */
static struct unit_directory *nodemgr_process_unit_directory
	(struct host_info *hi, struct node_entry *ne, octlet_t address, unsigned int *id,
	 struct unit_directory *parent)
{
	struct unit_directory *ud;
	quadlet_t quad;
	quadlet_t *infop;
	int length;
	struct unit_directory *ud_temp = NULL;

	if (!(ud = nodemgr_scan_unit_directory(ne, address)))
		goto unit_directory_error;

	ud->ne = ne;
	ud->address = address;
	ud->id = (*id)++;

	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
				 address, &quad))
		goto unit_directory_error;
	length = CONFIG_ROM_DIRECTORY_LENGTH(quad) ;
	address += 4;

	infop = (quadlet_t *) ud->quadlets;
	for (; length > 0; length--, address += 4) {
		int code;
		quadlet_t value;
		quadlet_t *quadp;

		if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
					 address, &quad))
			goto unit_directory_error;
		code = CONFIG_ROM_KEY(quad) ;
		value = CONFIG_ROM_VALUE(quad);

		switch (code) {
		case CONFIG_ROM_VENDOR_ID:
			ud->vendor_id = value;
			ud->flags |= UNIT_DIRECTORY_VENDOR_ID;

			if (ud->vendor_id)
				ud->vendor_oui = nodemgr_find_oui_name(ud->vendor_id);

			if ((ud->flags & UNIT_DIRECTORY_VENDOR_TEXT) != 0) {
				length--;
				address += 4;
				quadp = &(ud->quadlets[ud->length]);
				if (nodemgr_read_text_leaf(ne, address, quadp) == 0
				    && quadp[0] == 0 && quadp[1] == 0) {
				    	/* We only support minimal
					   ASCII and English. */
					quadp[ud->vendor_name_size] = 0;
					ud->vendor_name
						= (const char *) &(quadp[2]);
				}
			}
			break;

		case CONFIG_ROM_MODEL_ID:
			ud->model_id = value;
			ud->flags |= UNIT_DIRECTORY_MODEL_ID;
			if ((ud->flags & UNIT_DIRECTORY_MODEL_TEXT) != 0) {
				length--;
				address += 4;
				quadp = &(ud->quadlets[ud->length + ud->vendor_name_size + 1]);
				if (nodemgr_read_text_leaf(ne, address, quadp) == 0
				    && quadp[0] == 0 && quadp[1] == 0) {
				    	/* We only support minimal
					   ASCII and English. */
					quadp[ud->model_name_size] = 0;
					ud->model_name
						= (const char *) &(quadp[2]);
				}
			}
			break;

		case CONFIG_ROM_SPECIFIER_ID:
			ud->specifier_id = value;
			ud->flags |= UNIT_DIRECTORY_SPECIFIER_ID;
			break;

		case CONFIG_ROM_UNIT_SW_VERSION:
			ud->version = value;
			ud->flags |= UNIT_DIRECTORY_VERSION;
			break;

		case CONFIG_ROM_DESCRIPTOR_LEAF:
		case CONFIG_ROM_DESCRIPTOR_DIRECTORY:
			/* TODO: read strings... icons? */
			break;

		case CONFIG_ROM_LOGICAL_UNIT_DIRECTORY:
			ud->flags |= UNIT_DIRECTORY_HAS_LUN_DIRECTORY;
			ud_temp = nodemgr_process_unit_directory(hi, ne, address + value * 4, id,
								 parent);

			if (ud_temp == NULL)
				break;

			/* inherit unspecified values */
			if ((ud->flags & UNIT_DIRECTORY_VENDOR_ID) &&
				!(ud_temp->flags & UNIT_DIRECTORY_VENDOR_ID))
			{
				ud_temp->flags |=  UNIT_DIRECTORY_VENDOR_ID;
				ud_temp->vendor_id = ud->vendor_id;
				ud_temp->vendor_oui = ud->vendor_oui;
			}
			if ((ud->flags & UNIT_DIRECTORY_MODEL_ID) &&
				!(ud_temp->flags & UNIT_DIRECTORY_MODEL_ID))
			{
				ud_temp->flags |=  UNIT_DIRECTORY_MODEL_ID;
				ud_temp->model_id = ud->model_id;
			}
			if ((ud->flags & UNIT_DIRECTORY_SPECIFIER_ID) &&
				!(ud_temp->flags & UNIT_DIRECTORY_SPECIFIER_ID))
			{
				ud_temp->flags |=  UNIT_DIRECTORY_SPECIFIER_ID;
				ud_temp->specifier_id = ud->specifier_id;
			}
			if ((ud->flags & UNIT_DIRECTORY_VERSION) &&
				!(ud_temp->flags & UNIT_DIRECTORY_VERSION))
			{
				ud_temp->flags |=  UNIT_DIRECTORY_VERSION;
				ud_temp->version = ud->version;
			}

			break;

		default:
			/* Which types of quadlets do we want to
			   store?  Only count immediate values and
			   CSR offsets for now.  */
			code &= CONFIG_ROM_KEY_TYPE_MASK;
			if ((code & CONFIG_ROM_KEY_TYPE_LEAF) == 0)
				*infop++ = quad;
			break;
		}
	}

	memcpy(&ud->device, &nodemgr_dev_template_ud,
	       sizeof(ud->device));

	if (parent) {
		ud->flags |= UNIT_DIRECTORY_LUN_DIRECTORY;
		ud->device.parent = &parent->device;
	} else
		ud->device.parent = &ne->device;

	snprintf(ud->device.bus_id, BUS_ID_SIZE, "%s-%u",
		 ne->device.bus_id, ud->id);

	device_register(&ud->device);

	if (ud->vendor_oui)
		device_create_file(&ud->device, &dev_attr_ud_vendor_oui);
	nodemgr_create_ud_dev_files(ud);

	return ud;

unit_directory_error:	
	if (ud != NULL)
		kfree(ud);
	return NULL;
}


static void nodemgr_process_root_directory(struct host_info *hi, struct node_entry *ne)
{
	octlet_t address;
	quadlet_t quad;
	int length;
	unsigned int ud_id = 0;

	address = CSR_REGISTER_BASE + CSR_CONFIG_ROM;
	
	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
				 address, &quad))
		return;
	address += 4 + CONFIG_ROM_BUS_INFO_LENGTH(quad) * 4;

	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
				 address, &quad))
		return;
	length = CONFIG_ROM_ROOT_LENGTH(quad);
	address += 4;

	for (; length > 0; length--, address += 4) {
		int code, value;

		if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
					 address, &quad))
			return;
		code = CONFIG_ROM_KEY(quad);
		value = CONFIG_ROM_VALUE(quad);

		switch (code) {
		case CONFIG_ROM_VENDOR_ID:
			ne->vendor_id = value;

			if (ne->vendor_id)
				ne->vendor_oui = nodemgr_find_oui_name(ne->vendor_id);

			/* Now check if there is a vendor name text
			   string.  */
			if (ne->vendor_name != NULL) {
				length--;
				address += 4;
				if (nodemgr_read_text_leaf(ne, address, ne->quadlets) != 0
				    || ne->quadlets[0] != 0 || ne->quadlets[1] != 0)
				    	/* We only support minimal
					   ASCII and English. */
					ne->vendor_name = NULL;
				else
					device_create_file(&ne->device,
						&dev_attr_ne_vendor_name);
			}
			break;

		case CONFIG_ROM_NODE_CAPABILITES:
			ne->capabilities = value;
			break;

		case CONFIG_ROM_UNIT_DIRECTORY:
			nodemgr_process_unit_directory(hi, ne, address + value * 4, &ud_id,
						       NULL);
			break;			

		case CONFIG_ROM_DESCRIPTOR_LEAF:
		case CONFIG_ROM_DESCRIPTOR_DIRECTORY:
			/* TODO: read strings... icons? */
			break;
		}
	}
}

#ifdef CONFIG_HOTPLUG

static int nodemgr_hotplug(struct device *dev, char **envp, int num_envp,
			   char *buffer, int buffer_size)
{
	struct unit_directory *ud;
	char *scratch;
	int i = 0;
	int length = 0;

	if (!dev)
		return -ENODEV;

	/* Have to check driver_data, since on remove, driver == NULL */
	if (dev->driver_data == &nodemgr_driverdata_ne ||
	    dev->driver_data == &nodemgr_driverdata_host)
		return -ENODEV;

	ud = container_of(dev, struct unit_directory, device);

	scratch = buffer;

#define PUT_ENVP(fmt,val) 					\
do {								\
	envp[i++] = scratch;					\
	length += snprintf(scratch, buffer_size - length,	\
			   fmt, val);				\
	if ((buffer_size - length <= 0) || (i >= num_envp))	\
		return -ENOMEM;					\
	++length;						\
	scratch = buffer + length;				\
} while (0)

	PUT_ENVP("VENDOR_ID=%06x", ud->vendor_id);
	PUT_ENVP("MODEL_ID=%06x", ud->model_id);
	PUT_ENVP("GUID=%016Lx", (unsigned long long)ud->ne->guid);
	PUT_ENVP("SPECIFIER_ID=%06x", ud->specifier_id);
	PUT_ENVP("VERSION=%06x", ud->version);

#undef PUT_ENVP

	envp[i] = 0;

	return 0;
}

#else

static int nodemgr_hotplug(struct device *dev, char **envp, int num_envp,
			   char *buffer, int buffer_size)
{
	return -ENODEV;
} 

#endif /* CONFIG_HOTPLUG */


int hpsb_register_protocol(struct hpsb_protocol_driver *driver)
{
	driver_register(&driver->driver);
	nodemgr_create_drv_files(driver);

	/*
	 * Right now registration always succeeds, but maybe we should
	 * detect clashes in protocols handled by other drivers.
     * DRD> No because multiple drivers are needed to handle certain devices.
     * For example, a DV camera is an IEC 61883 device (dv1394) and AV/C (raw1394).
     * This will become less an issue with libiec61883 using raw1394.
     *
     * BenC: But can we handle this with an ALLOW_SHARED flag for a
     * protocol? When we get an SBP-3 driver, it will be nice if they were
     * mutually exclusive, since SBP-3 can handle SBP-2 protocol.
     *
     * Not to mention that we currently do not seem to support multiple
     * drivers claiming the same unitdirectory. If we implement both of
     * those, then we'll need to keep probing when a driver claims a
     * unitdirectory, but is sharable.
	 */

	return 0;
}

void hpsb_unregister_protocol(struct hpsb_protocol_driver *driver)
{
	nodemgr_remove_drv_files(driver);
	/* This will subsequently disconnect all devices that our driver
	 * is attached to. */
	driver_unregister(&driver->driver);
}

static void nodemgr_process_config_rom(struct host_info *hi,
		struct node_entry *ne, quadlet_t busoptions)
{
	ne->busopt.irmc		= (busoptions >> 31) & 1;
	ne->busopt.cmc		= (busoptions >> 30) & 1;
	ne->busopt.isc		= (busoptions >> 29) & 1;
	ne->busopt.bmc		= (busoptions >> 28) & 1;
	ne->busopt.pmc		= (busoptions >> 27) & 1;
	ne->busopt.cyc_clk_acc	= (busoptions >> 16) & 0xff;
	ne->busopt.max_rec	= 1 << (((busoptions >> 12) & 0xf) + 1);
	ne->busopt.generation	= (busoptions >> 4) & 0xf;
	ne->busopt.lnkspd	= busoptions & 0x7;

	HPSB_VERBOSE("NodeMgr: raw=0x%08x irmc=%d cmc=%d isc=%d bmc=%d pmc=%d "
		     "cyc_clk_acc=%d max_rec=%d gen=%d lspd=%d",
		     busoptions, ne->busopt.irmc, ne->busopt.cmc,
		     ne->busopt.isc, ne->busopt.bmc, ne->busopt.pmc,
		     ne->busopt.cyc_clk_acc, ne->busopt.max_rec,
		     ne->busopt.generation, ne->busopt.lnkspd);

	device_remove_file(&ne->device, &dev_attr_ne_vendor_oui);

	nodemgr_process_root_directory(hi, ne);

	if (ne->vendor_oui)
		device_create_file(&ne->device, &dev_attr_ne_vendor_oui);
}


/* Searches the list of ud's that match a ne as the parent. If the ud has
 * a driver associated with it, we call that driver's update function
 * with the ud as the argument. */
static int nodemgr_driver_search_cb(struct device *dev, void *__data)
{
	struct node_entry *ne = __data;
	struct unit_directory *ud;

	if (dev->driver_data == &nodemgr_driverdata_ne ||
	    dev->driver_data == &nodemgr_driverdata_host)
		return 0;

	ud = container_of(dev, struct unit_directory, device);

	if (&ne->device != ud->device.parent)
		return 0;

	if (ud->device.driver) {
		struct hpsb_protocol_driver *pdrv;

		pdrv = container_of(ud->device.driver,
				struct hpsb_protocol_driver, driver);

		if (pdrv->update)
			pdrv->update(ud);
	}

	return 0;
}

/*
 * This function updates nodes that were present on the bus before the
 * reset and still are after the reset.  The nodeid and the config rom
 * may have changed, and the drivers managing this device must be
 * informed that this device just went through a bus reset, to allow
 * the to take whatever actions required.
 */
static void nodemgr_update_node(struct node_entry *ne, quadlet_t busoptions,
				struct host_info *hi, nodeid_t nodeid,
				unsigned int generation)
{
	if (ne->nodeid != nodeid) {
		HPSB_DEBUG("Node changed: " NODE_BUS_FMT " -> " NODE_BUS_FMT,
			   NODE_BUS_ARGS(ne->host, ne->nodeid),
			   NODE_BUS_ARGS(ne->host, nodeid));
		ne->nodeid = nodeid;
	}

	if (ne->busopt.generation != ((busoptions >> 4) & 0xf)) {
		/* If the node's configrom generation has changed, we
		 * unregister all the unit directories. */
		nodemgr_remove_node_uds(ne);

		/* With all the ud's gone, mark the generation current,
		 * this way the probe will succeed. */
		ne->generation = generation;

		/* This will re-register our unitdir's */
		nodemgr_process_config_rom (hi, ne, busoptions);
	} else
		ne->generation = generation;

	/* Update unit_dirs with attached drivers */
	bus_for_each_dev(&ieee1394_bus_type, NULL, ne,
			 nodemgr_driver_search_cb);
}

static int read_businfo_block(struct hpsb_host *host, nodeid_t nodeid, unsigned int generation,
			      quadlet_t *buffer, int buffer_length)
{
	octlet_t addr = CSR_REGISTER_BASE + CSR_CONFIG_ROM;
	unsigned header_size;
	int i;

	/* IEEE P1212 says that devices should support 64byte block
	 * reads, aligned on 64byte boundaries. That doesn't seem to
	 * work though, and we are forced to doing quadlet sized
	 * reads.  */

	HPSB_VERBOSE("Initiating ConfigROM request for node " NODE_BUS_FMT,
		     NODE_BUS_ARGS(host, nodeid));

	/* 
	 * Must retry a few times if config rom read returns zero (how long?). Will
	 * not normally occur, but we should do the right thing. For example, with
	 * some sbp2 devices, the bridge chipset cannot return valid config rom reads
	 * immediately after power-on, since they need to detect the type of 
	 * device attached (disk or CD-ROM).
	 */
	for (i = 0; i < 4; i++) {
		if (nodemgr_read_quadlet(host, nodeid, generation,
					 addr, &buffer[0]) < 0) {
			HPSB_ERR("ConfigROM quadlet transaction error for node "
				 NODE_BUS_FMT, NODE_BUS_ARGS(host, nodeid));
			return -1;
		}
		if (buffer[0])
			break;

		set_current_state(TASK_INTERRUPTIBLE);
		if (schedule_timeout (HZ/4))
			return -1;
	}

	header_size = buffer[0] >> 24;
	addr += 4;

	if (header_size == 1) {
		HPSB_INFO("Node " NODE_BUS_FMT " has a minimal ROM.  "
			  "Vendor is %08x",
			  NODE_BUS_ARGS(host, nodeid), buffer[0] & 0x00ffffff);
		return -1;
	}

	if (header_size < 4) {
		HPSB_INFO("Node " NODE_BUS_FMT " has non-standard ROM "
			  "format (%d quads), cannot parse",
			  NODE_BUS_ARGS(host, nodeid), header_size);
		return -1;
	}

	for (i = 1; i < buffer_length; i++, addr += 4) {
		if (nodemgr_read_quadlet(host, nodeid, generation,
					 addr, &buffer[i]) < 0) {
			HPSB_ERR("ConfigROM quadlet transaction "
				 "error for node " NODE_BUS_FMT,
				 NODE_BUS_ARGS(host, nodeid));
			return -1;
		}
	}

	return 0;
}		


/* This is where we probe the nodes for their information and provided
 * features.  */
static void nodemgr_node_probe_one(struct host_info *hi,
				   nodeid_t nodeid, int generation)
{
	struct hpsb_host *host = hi->host;
	struct node_entry *ne;
	quadlet_t buffer[5];
	octlet_t guid;

	/* We need to detect when the ConfigROM's generation has changed,
	 * so we only update the node's info when it needs to be.  */

	if (read_businfo_block (host, nodeid, generation,
				buffer, sizeof(buffer) >> 2))
		return;

	if (buffer[1] != IEEE1394_BUSID_MAGIC) {
		/* This isn't a 1394 device, but we let it slide. There
		 * was a report of a device with broken firmware which
		 * reported '2394' instead of '1394', which is obviously a
		 * mistake. One would hope that a non-1394 device never
		 * gets connected to Firewire bus. If someone does, we
		 * shouldn't be held responsible, so we'll allow it with a
		 * warning.  */
		HPSB_WARN("Node " NODE_BUS_FMT " has invalid busID magic [0x%08x]",
			 NODE_BUS_ARGS(host, nodeid), buffer[1]);
	}

	guid = ((u64)buffer[3] << 32) | buffer[4];
	ne = find_entry_by_guid(guid);

	if (!ne)
		nodemgr_create_node(guid, buffer[2], hi, nodeid, generation);
	else
		nodemgr_update_node(ne, buffer[2], hi, nodeid, generation);

	return;
}


struct cleanup_baton {
	unsigned int generation;
	struct hpsb_host *host;
	struct node_entry *ne;
};

static int nodemgr_remove_node(struct device *dev, void *__data)
{
	struct cleanup_baton *cleanup = __data;
	struct node_entry *ne;

	if (dev->driver_data != &nodemgr_driverdata_ne)
		return 0;

	ne = container_of(dev, struct node_entry, device);

	if (ne->host != cleanup->host)
		return 0;

	if (ne->generation != cleanup->generation) {
		cleanup->ne = ne;
		return 1;
	}

	return 0;
}


static void nodemgr_node_probe(struct host_info *hi, int generation)
{
	int count;
	struct hpsb_host *host = hi->host;
	struct selfid *sid = (struct selfid *)host->topology_map;
	nodeid_t nodeid = LOCAL_BUS;

	/* Scan each node on the bus */
	for (count = host->selfid_count; count; count--, sid++) {
		if (sid->extended)
			continue;

		if (!sid->link_active) {
			nodeid++;
			continue;
		}
		nodemgr_node_probe_one(hi, nodeid++, generation);
	}

	/* If we had a bus reset while we were scanning the bus, it is
	 * possible that we did not probe all nodes.  In that case, we
	 * skip the clean up for now, since we could remove nodes that
	 * were still on the bus.  The bus reset increased hi->reset_sem,
	 * so there's a bus scan pending which will do the clean up
	 * eventually. */
	if (generation == get_hpsb_generation(host)) {
		struct cleanup_baton cleanup;

		cleanup.generation = generation;
		cleanup.host = host;

		/* This will iterate until all devices that do not match
		 * the generation are removed. */
		while (bus_for_each_dev(&ieee1394_bus_type, NULL, &cleanup,
					nodemgr_remove_node)) {
			struct node_entry *ne = cleanup.ne;

			HPSB_DEBUG("Node removed: ID:BUS[" NODE_BUS_FMT "]  GUID[%016Lx]",
				   NODE_BUS_ARGS(host, ne->nodeid), (unsigned long long)ne->guid);

			nodemgr_remove_ne(ne);
		}

		/* Now let's tell the bus to rescan our devices. This may
		 * seem like overhead, but the driver-model core will only
		 * scan a device for a driver when either the device is
		 * added, or when a new driver is added. A bus reset is a
		 * good reason to rescan devices that were there before.
		 * For example, an sbp2 device may become available for
		 * login, if the host that held it was just removed. */
		bus_rescan_devices(&ieee1394_bus_type);
	}

	return;
}

/* Because we are a 1394a-2000 compliant IRM, we need to inform all the other
 * nodes of the broadcast channel.  (Really we're only setting the validity
 * bit). Other IRM responsibilities go in here as well. */
static void nodemgr_do_irm_duties(struct hpsb_host *host)
{
	quadlet_t bc;
        
	if (!host->is_irm)
		return;

	host->csr.broadcast_channel |= 0x40000000;  /* set validity bit */

	bc = cpu_to_be32(host->csr.broadcast_channel);

	hpsb_write(host, LOCAL_BUS | ALL_NODES, get_hpsb_generation(host),
		   (CSR_REGISTER_BASE | CSR_BROADCAST_CHANNEL),
		   &bc, sizeof(quadlet_t));

	/* If there is no bus manager then we should set the root node's
	 * force_root bit to promote bus stability per the 1394
	 * spec. (8.4.2.6) */
	if (host->busmgr_id == 0xffff && host->node_count > 1)
	{
		u16 root_node = host->node_count - 1;
		struct node_entry *ne = find_entry_by_nodeid(host, root_node | LOCAL_BUS);

		if (ne && ne->busopt.cmc)
			hpsb_send_phy_config(host, root_node, -1);
		else {
			HPSB_DEBUG("The root node is not cycle master capable; "
				   "selecting a new root node and resetting...");
			hpsb_send_phy_config(host, NODEID_TO_NODE(host->node_id), -1);
			hpsb_reset_bus(host, LONG_RESET_FORCE_ROOT);
		}
	}
}

/* We need to ensure that if we are not the IRM, that the IRM node is capable of
 * everything we can do, otherwise issue a bus reset and try to become the IRM
 * ourselves. */
static int nodemgr_check_irm_capability(struct hpsb_host *host, int cycles)
{
	quadlet_t bc;
	int status;

	if (host->is_irm)
		return 1;

	status = hpsb_read(host, LOCAL_BUS | (host->irm_id),
			   get_hpsb_generation(host),
			   (CSR_REGISTER_BASE | CSR_BROADCAST_CHANNEL),
			   &bc, sizeof(quadlet_t));

	if (status < 0 || !(be32_to_cpu(bc) & 0x80000000)) {
		/* The current irm node does not have a valid BROADCAST_CHANNEL
		 * register and we do, so reset the bus with force_root set */
		HPSB_DEBUG("Current remote IRM is not 1394a-2000 compliant, resetting...");

		if (cycles >= 5) {
			/* Oh screw it! Just leave the bus as it is */
			HPSB_DEBUG("Stopping reset loop for IRM sanity");
			return 1;
		}

		hpsb_send_phy_config(host, NODEID_TO_NODE(host->node_id), -1);
		hpsb_reset_bus(host, LONG_RESET_FORCE_ROOT);

		return 0;
	}

	return 1;
}

static int nodemgr_host_thread(void *__hi)
{
	struct host_info *hi = (struct host_info *)__hi;
	struct hpsb_host *host = hi->host;
	int reset_cycles = 0;

	/* No userlevel access needed */
	daemonize(hi->daemon_name);
	allow_signal(SIGTERM);

	/* Setup our device-model entries */
	device_register(&host->device);
	nodemgr_create_host_dev_files(host);

	/* Sit and wait for a signal to probe the nodes on the bus. This
	 * happens when we get a bus reset. */
	while (!down_interruptible(&hi->reset_sem) &&
	       !down_interruptible(&nodemgr_serialize)) {
		unsigned int generation = 0;
		int i;

		/* Pause for 1/4 second in 1/16 second intervals,
		 * to make sure things settle down. */
		for (i = 0; i < 4 ; i++) {
			set_current_state(TASK_INTERRUPTIBLE);
			if (schedule_timeout(HZ/16))
				goto caught_signal;

			/* Now get the generation in which the node ID's we collect
			 * are valid.  During the bus scan we will use this generation
			 * for the read transactions, so that if another reset occurs
			 * during the scan the transactions will fail instead of
			 * returning bogus data. */
			generation = get_hpsb_generation(host);

			/* If we get a reset before we are done waiting, then
			 * start the the waiting over again */
			while (!down_trylock(&hi->reset_sem))
				i = 0;
		}

		if (!nodemgr_check_irm_capability(host, reset_cycles++)) {
			/* Do nothing, we are resetting */
			up(&nodemgr_serialize);
			continue;
		}

		reset_cycles = 0;

		nodemgr_node_probe(hi, generation);
		nodemgr_do_irm_duties(host);

		/* Update some of our sysfs symlinks */
		nodemgr_update_host_dev_links(host);

		up(&nodemgr_serialize);
	}

caught_signal:
	HPSB_VERBOSE("NodeMgr: Exiting thread");

	complete_and_exit(&hi->exited, 0);
}

struct node_entry *hpsb_guid_get_entry(u64 guid)
{
        struct node_entry *ne;

	down(&nodemgr_serialize);
        ne = find_entry_by_guid(guid);
	up(&nodemgr_serialize);

        return ne;
}

struct node_entry *hpsb_nodeid_get_entry(struct hpsb_host *host, nodeid_t nodeid)
{
	struct node_entry *ne;

	down(&nodemgr_serialize);
	ne = find_entry_by_nodeid(host, nodeid);
	up(&nodemgr_serialize);

	return ne;
}

/* The following four convenience functions use a struct node_entry
 * for addressing a node on the bus.  They are intended for use by any
 * process context, not just the nodemgr thread, so we need to be a
 * little careful when reading out the node ID and generation.  The
 * thing that can go wrong is that we get the node ID, then a bus
 * reset occurs, and then we read the generation.  The node ID is
 * possibly invalid, but the generation is current, and we end up
 * sending a packet to a the wrong node.
 *
 * The solution is to make sure we read the generation first, so that
 * if a reset occurs in the process, we end up with a stale generation
 * and the transactions will fail instead of silently using wrong node
 * ID's.
 */

void hpsb_node_fill_packet(struct node_entry *ne, struct hpsb_packet *pkt)
{
        pkt->host = ne->host;
        pkt->generation = ne->generation;
	barrier();
        pkt->node_id = ne->nodeid;
}

int hpsb_node_read(struct node_entry *ne, u64 addr,
		   quadlet_t *buffer, size_t length)
{
	unsigned int generation = ne->generation;

	barrier();
	return hpsb_read(ne->host, ne->nodeid, generation,
			 addr, buffer, length);
}

int hpsb_node_write(struct node_entry *ne, u64 addr, 
		    quadlet_t *buffer, size_t length)
{
	unsigned int generation = ne->generation;

	barrier();
	return hpsb_write(ne->host, ne->nodeid, generation,
			  addr, buffer, length);
}

int hpsb_node_lock(struct node_entry *ne, u64 addr, 
		   int extcode, quadlet_t *data, quadlet_t arg)
{
	unsigned int generation = ne->generation;

	barrier();
	return hpsb_lock(ne->host, ne->nodeid, generation,
			 addr, extcode, data, arg);
}

static void nodemgr_add_host(struct hpsb_host *host)
{
	struct host_info *hi;

	hi = hpsb_create_hostinfo(&nodemgr_highlevel, host, sizeof(*hi));

	if (!hi) {
		HPSB_ERR ("NodeMgr: out of memory in add host");
		return;
	}

	hi->host = host;
	init_completion(&hi->exited);
        sema_init(&hi->reset_sem, 0);

	memcpy(&host->device, &nodemgr_dev_template_host,
	       sizeof(host->device));
	host->device.parent = &host->pdev->dev;
	snprintf(host->device.bus_id, BUS_ID_SIZE, "fw-host%d", host->id);

	sprintf(hi->daemon_name, "knodemgrd_%d", host->id);

	hi->pid = kernel_thread(nodemgr_host_thread, hi, CLONE_KERNEL);

	if (hi->pid < 0) {
		HPSB_ERR ("NodeMgr: failed to start %s thread for %s",
			  hi->daemon_name, host->driver->name);
		hpsb_destroy_hostinfo(&nodemgr_highlevel, host);
		return;
	}

	return;
}

static void nodemgr_host_reset(struct hpsb_host *host)
{
	struct host_info *hi = hpsb_get_hostinfo(&nodemgr_highlevel, host);

	if (hi != NULL) {
		HPSB_VERBOSE("NodeMgr: Processing host reset for %s", hi->daemon_name);
		up(&hi->reset_sem);
	} else
		HPSB_ERR ("NodeMgr: could not process reset of unused host");

	return;
}

static void nodemgr_remove_host(struct hpsb_host *host)
{
	struct host_info *hi = hpsb_get_hostinfo(&nodemgr_highlevel, host);

	if (hi) {
		if (hi->pid >= 0) {
			kill_proc(hi->pid, SIGTERM, 1);
			wait_for_completion(&hi->exited);
			nodemgr_remove_host_dev(&host->device);
			device_unregister(&host->device);
		}
	} else
		HPSB_ERR("NodeMgr: host %s does not exist, cannot remove",
			 host->driver->name);

	return;
}

static struct hpsb_highlevel nodemgr_highlevel = {
	.name =		"Node manager",
	.add_host =	nodemgr_add_host,
	.host_reset =	nodemgr_host_reset,
	.remove_host =	nodemgr_remove_host,
};

void init_ieee1394_nodemgr(void)
{
	bus_register(&ieee1394_bus_type);
	driver_register(&nodemgr_driver_host);
	driver_register(&nodemgr_driver_ne);

	hpsb_register_highlevel(&nodemgr_highlevel);
}

void cleanup_ieee1394_nodemgr(void)
{
        hpsb_unregister_highlevel(&nodemgr_highlevel);

	driver_unregister(&nodemgr_driver_ne);
	driver_unregister(&nodemgr_driver_host);
	bus_unregister(&ieee1394_bus_type);
}
