rio-scan.c

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	rio_mport_read_config_32(mport, destid, hopcount, RIO_SWP_INFO_CAR,
				 &result);

	return (u8) (result & 0xff);
}

/**
 * rio_get_swpinfo_tports- Gets total number of ports on the switch
 * @mport: Master port to send transaction
 * @destid: Destination ID associated with the switch
 * @hopcount: Number of hops to the device
 *
 * Returns total numbers of ports implemented by the switch device.
 */
static u8 rio_get_swpinfo_tports(struct rio_mport *mport, u16 destid,
				 u8 hopcount)
{
	u32 result;

	rio_mport_read_config_32(mport, destid, hopcount, RIO_SWP_INFO_CAR,
				 &result);

	return RIO_GET_TOTAL_PORTS(result);
}

/**
 * rio_net_add_mport- Add a master port to a RIO network
 * @net: RIO network
 * @port: Master port to add
 *
 * Adds a master port to the network list of associated master
 * ports..
 */
static void rio_net_add_mport(struct rio_net *net, struct rio_mport *port)
{
	spin_lock(&rio_global_list_lock);
	list_add_tail(&port->nnode, &net->mports);
	spin_unlock(&rio_global_list_lock);
}

/**
 * rio_enum_peer- Recursively enumerate a RIO network through a master port
 * @net: RIO network being enumerated
 * @port: Master port to send transactions
 * @hopcount: Number of hops into the network
 *
 * Recursively enumerates a RIO network.  Transactions are sent via the
 * master port passed in @port.
 */
static int rio_enum_peer(struct rio_net *net, struct rio_mport *port,
			 u8 hopcount)
{
	int port_num;
	int num_ports;
	int cur_destid;
	int sw_destid;
	int sw_inport;
	struct rio_dev *rdev;
	u16 destid;
	int tmp;

	if (rio_get_host_deviceid_lock(port, hopcount) == port->host_deviceid) {
		pr_debug("RIO: PE already discovered by this host\n");
		/*
		 * Already discovered by this host. Add it as another
		 * master port for the current network.
		 */
		rio_net_add_mport(net, port);
		return 0;
	}

	/* Attempt to acquire device lock */
	rio_mport_write_config_32(port, RIO_ANY_DESTID, hopcount,
				  RIO_HOST_DID_LOCK_CSR, port->host_deviceid);
	while ((tmp = rio_get_host_deviceid_lock(port, hopcount))
	       < port->host_deviceid) {
		/* Delay a bit */
		mdelay(1);
		/* Attempt to acquire device lock again */
		rio_mport_write_config_32(port, RIO_ANY_DESTID, hopcount,
					  RIO_HOST_DID_LOCK_CSR,
					  port->host_deviceid);
	}

	if (rio_get_host_deviceid_lock(port, hopcount) > port->host_deviceid) {
		pr_debug(
		    "RIO: PE locked by a higher priority host...retreating\n");
		return -1;
	}

	/* Setup new RIO device */
	if ((rdev = rio_setup_device(net, port, RIO_ANY_DESTID, hopcount, 1))) {
		/* Add device to the global and bus/net specific list. */
		list_add_tail(&rdev->net_list, &net->devices);
	} else
		return -1;

	if (rio_is_switch(rdev)) {
		next_switchid++;
		sw_inport = rio_get_swpinfo_inport(port, RIO_ANY_DESTID, hopcount);
		rio_route_add_entry(port, rdev->rswitch, RIO_GLOBAL_TABLE,
				    port->host_deviceid, sw_inport);
		rdev->rswitch->route_table[port->host_deviceid] = sw_inport;

		for (destid = 0; destid < next_destid; destid++) {
			if (destid == port->host_deviceid)
				continue;
			rio_route_add_entry(port, rdev->rswitch, RIO_GLOBAL_TABLE,
					    destid, sw_inport);
			rdev->rswitch->route_table[destid] = sw_inport;
		}

		num_ports =
		    rio_get_swpinfo_tports(port, RIO_ANY_DESTID, hopcount);
		pr_debug(
		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
		    rio_name(rdev), rdev->vid, rdev->did, num_ports);
		sw_destid = next_destid;
		for (port_num = 0; port_num < num_ports; port_num++) {
			if (sw_inport == port_num)
				continue;

			cur_destid = next_destid;

			if (rio_sport_is_active
			    (port, RIO_ANY_DESTID, hopcount, port_num)) {
				pr_debug(
				    "RIO: scanning device on port %d\n",
				    port_num);
				rio_route_add_entry(port, rdev->rswitch,
						    RIO_GLOBAL_TABLE,
						    RIO_ANY_DESTID, port_num);

				if (rio_enum_peer(net, port, hopcount + 1) < 0)
					return -1;

				/* Update routing tables */
				if (next_destid > cur_destid) {
					for (destid = cur_destid;
					     destid < next_destid; destid++) {
						if (destid == port->host_deviceid)
							continue;
						rio_route_add_entry(port, rdev->rswitch,
								    RIO_GLOBAL_TABLE,
								    destid,
								    port_num);
						rdev->rswitch->
						    route_table[destid] =
						    port_num;
					}
				}
			}
		}

		/* Check for empty switch */
		if (next_destid == sw_destid) {
			next_destid++;
			if (next_destid == port->host_deviceid)
				next_destid++;
		}

		rdev->rswitch->destid = sw_destid;
	} else
		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
		    rio_name(rdev), rdev->vid, rdev->did);

	return 0;
}

/**
 * rio_enum_complete- Tests if enumeration of a network is complete
 * @port: Master port to send transaction
 *
 * Tests the Component Tag CSR for presence of the magic enumeration
 * complete flag. Return %1 if enumeration is complete or %0 if
 * enumeration is incomplete.
 */
static int rio_enum_complete(struct rio_mport *port)
{
	u32 tag_csr;
	int ret = 0;

	rio_local_read_config_32(port, RIO_COMPONENT_TAG_CSR, &tag_csr);

	if (tag_csr == RIO_ENUM_CMPL_MAGIC)
		ret = 1;

	return ret;
}

/**
 * rio_disc_peer- Recursively discovers a RIO network through a master port
 * @net: RIO network being discovered
 * @port: Master port to send transactions
 * @destid: Current destination ID in network
 * @hopcount: Number of hops into the network
 *
 * Recursively discovers a RIO network.  Transactions are sent via the
 * master port passed in @port.
 */
static int
rio_disc_peer(struct rio_net *net, struct rio_mport *port, u16 destid,
	      u8 hopcount)
{
	u8 port_num, route_port;
	int num_ports;
	struct rio_dev *rdev;
	u16 ndestid;

	/* Setup new RIO device */
	if ((rdev = rio_setup_device(net, port, destid, hopcount, 0))) {
		/* Add device to the global and bus/net specific list. */
		list_add_tail(&rdev->net_list, &net->devices);
	} else
		return -1;

	if (rio_is_switch(rdev)) {
		next_switchid++;

		/* Associated destid is how we accessed this switch */
		rdev->rswitch->destid = destid;

		num_ports = rio_get_swpinfo_tports(port, destid, hopcount);
		pr_debug(
		    "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
		    rio_name(rdev), rdev->vid, rdev->did, num_ports);
		for (port_num = 0; port_num < num_ports; port_num++) {
			if (rio_get_swpinfo_inport(port, destid, hopcount) ==
			    port_num)
				continue;

			if (rio_sport_is_active
			    (port, destid, hopcount, port_num)) {
				pr_debug(
				    "RIO: scanning device on port %d\n",
				    port_num);
				for (ndestid = 0; ndestid < RIO_ANY_DESTID;
				     ndestid++) {
					rio_route_get_entry(port, rdev->rswitch,
							    RIO_GLOBAL_TABLE,
							    ndestid,
							    &route_port);
					if (route_port == port_num)
						break;
				}

				if (rio_disc_peer
				    (net, port, ndestid, hopcount + 1) < 0)
					return -1;
			}
		}
	} else
		pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
		    rio_name(rdev), rdev->vid, rdev->did);

	return 0;
}

/**
 * rio_mport_is_active- Tests if master port link is active
 * @port: Master port to test
 *
 * Reads the port error status CSR for the master port to
 * determine if the port has an active link.  Returns
 * %PORT_N_ERR_STS_PORT_OK if the  master port is active
 * or %0 if it is inactive.
 */
static int rio_mport_is_active(struct rio_mport *port)
{
	u32 result = 0;
	u32 ext_ftr_ptr;
	int *entry = rio_mport_phys_table;

	do {
		if ((ext_ftr_ptr =
		     rio_mport_get_feature(port, 1, 0, 0, *entry)))
			break;
	} while (*++entry >= 0);

	if (ext_ftr_ptr)
		rio_local_read_config_32(port,
					 ext_ftr_ptr +
					 RIO_PORT_N_ERR_STS_CSR(port->index),
					 &result);

	return (result & PORT_N_ERR_STS_PORT_OK);
}

/**
 * rio_alloc_net- Allocate and configure a new RIO network
 * @port: Master port associated with the RIO network
 *
 * Allocates a RIO network structure, initializes per-network
 * list heads, and adds the associated master port to the
 * network list of associated master ports. Returns a
 * RIO network pointer on success or %NULL on failure.
 */
static struct rio_net __devinit *rio_alloc_net(struct rio_mport *port)
{
	struct rio_net *net;

	net = kzalloc(sizeof(struct rio_net), GFP_KERNEL);
	if (net) {
		INIT_LIST_HEAD(&net->node);
		INIT_LIST_HEAD(&net->devices);
		INIT_LIST_HEAD(&net->mports);
		list_add_tail(&port->nnode, &net->mports);
		net->hport = port;
		net->id = next_net++;
	}
	return net;
}

/**
 * rio_update_route_tables- Updates route tables in switches
 * @port: Master port associated with the RIO network
 *
 * For each enumerated device, ensure that each switch in a system
 * has correct routing entries. Add routes for devices that where
 * unknown dirung the first enumeration pass through the switch.
 */
static void rio_update_route_tables(struct rio_mport *port)
{
	struct rio_dev *rdev;
	struct rio_switch *rswitch;
	u8 sport;
	u16 destid;

	list_for_each_entry(rdev, &rio_devices, global_list) {

		destid = (rio_is_switch(rdev))?rdev->rswitch->destid:rdev->destid;

		list_for_each_entry(rswitch, &rio_switches, node) {

			if (rio_is_switch(rdev)	&& (rdev->rswitch == rswitch))
				continue;

			if (RIO_INVALID_ROUTE == rswitch->route_table[destid]) {

				sport = rio_get_swpinfo_inport(port,
						rswitch->destid, rswitch->hopcount);

				if (rswitch->add_entry)	{
					rio_route_add_entry(port, rswitch, RIO_GLOBAL_TABLE, destid, sport);
					rswitch->route_table[destid] = sport;
				}
			}
		}
	}
}

/**
 * rio_enum_mport- Start enumeration through a master port
 * @mport: Master port to send transactions
 *
 * Starts the enumeration process. If somebody has enumerated our
 * master port device, then give up. If not and we have an active
 * link, then start recursive peer enumeration. Returns %0 if
 * enumeration succeeds or %-EBUSY if enumeration fails.
 */
int rio_enum_mport(struct rio_mport *mport)
{
	struct rio_net *net = NULL;
	int rc = 0;

	printk(KERN_INFO "RIO: enumerate master port %d, %s\n", mport->id,
	       mport->name);
	/* If somebody else enumerated our master port device, bail. */
	if (rio_enum_host(mport) < 0) {
		printk(KERN_INFO
		       "RIO: master port %d device has been enumerated by a remote host\n",
		       mport->id);
		rc = -EBUSY;
		goto out;
	}

	/* If master port has an active link, allocate net and enum peers */
	if (rio_mport_is_active(mport)) {
		if (!(net = rio_alloc_net(mport))) {
			printk(KERN_ERR "RIO: failed to allocate new net\n");
			rc = -ENOMEM;
			goto out;
		}
		if (rio_enum_peer(net, mport, 0) < 0) {
			/* A higher priority host won enumeration, bail. */
			printk(KERN_INFO
			       "RIO: master port %d device has lost enumeration to a remote host\n",
			       mport->id);
			rio_clear_locks(mport);
			rc = -EBUSY;
			goto out;
		}
		rio_update_route_tables(mport);
		rio_clear_locks(mport);
	} else {
		printk(KERN_INFO "RIO: master port %d link inactive\n",
		       mport->id);
		rc = -EINVAL;
	}

      out:
	return rc;
}

/**
 * rio_build_route_tables- Generate route tables from switch route entries
 *
 * For each switch device, generate a route table by copying existing
 * route entries from the switch.
 */
static void rio_build_route_tables(void)
{
	struct rio_dev *rdev;
	int i;
	u8 sport;

	list_for_each_entry(rdev, &rio_devices, global_list)
	    if (rio_is_switch(rdev))
		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES; i++) {
			if (rio_route_get_entry
			    (rdev->net->hport, rdev->rswitch, RIO_GLOBAL_TABLE,
			     i, &sport) < 0)
				continue;
			rdev->rswitch->route_table[i] = sport;
		}
}

/**
 * rio_enum_timeout- Signal that enumeration timed out
 * @data: Address of timeout flag.
 *
 * When the enumeration complete timer expires, set a flag that
 * signals to the discovery process that enumeration did not
 * complete in a sane amount of time.
 */
static void rio_enum_timeout(unsigned long data)
{
	/* Enumeration timed out, set flag */
	*(int *)data = 1;
}

/**
 * rio_disc_mport- Start discovery through a master port
 * @mport: Master port to send transactions
 *
 * Starts the discovery process. If we have an active link,
 * then wait for the signal that enumeration is complete.
 * When enumeration completion is signaled, start recursive
 * peer discovery. Returns %0 if discovery succeeds or %-EBUSY
 * on failure.
 */
int rio_disc_mport(struct rio_mport *mport)
{
	struct rio_net *net = NULL;
	int enum_timeout_flag = 0;

	printk(KERN_INFO "RIO: discover master port %d, %s\n", mport->id,
	       mport->name);

	/* If master port has an active link, allocate net and discover peers */
	if (rio_mport_is_active(mport)) {
		if (!(net = rio_alloc_net(mport))) {
			printk(KERN_ERR "RIO: Failed to allocate new net\n");
			goto bail;
		}

		pr_debug("RIO: wait for enumeration complete...");

		rio_enum_timer.expires =
		    jiffies + CONFIG_RAPIDIO_DISC_TIMEOUT * HZ;
		rio_enum_timer.data = (unsigned long)&enum_timeout_flag;
		add_timer(&rio_enum_timer);
		while (!rio_enum_complete(mport)) {
			mdelay(1);
			if (enum_timeout_flag) {
				del_timer_sync(&rio_enum_timer);
				goto timeout;
			}
		}
		del_timer_sync(&rio_enum_timer);

		pr_debug("done\n");
		if (rio_disc_peer(net, mport, RIO_ANY_DESTID, 0) < 0) {
			printk(KERN_INFO
			       "RIO: master port %d device has failed discovery\n",
			       mport->id);
			goto bail;
		}

		rio_build_route_tables();
	}

	return 0;

      timeout:
	pr_debug("timeout\n");
      bail:
	return -EBUSY;
}