[deliverable/linux.git] / drivers / scsi / isci / port_config.c

/*
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * 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., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 * The full GNU General Public License is included in this distribution
 * in the file called LICENSE.GPL.
 *
 * BSD LICENSE
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *   * Neither the name of Intel Corporation nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "host.h"
#include "timers.h"

#define SCIC_SDS_MPC_RECONFIGURATION_TIMEOUT    (10)
#define SCIC_SDS_APC_RECONFIGURATION_TIMEOUT    (10)
#define SCIC_SDS_APC_WAIT_LINK_UP_NOTIFICATION  (100)

enum SCIC_SDS_APC_ACTIVITY {
        SCIC_SDS_APC_SKIP_PHY,
        SCIC_SDS_APC_ADD_PHY,
        SCIC_SDS_APC_START_TIMER,

        SCIC_SDS_APC_ACTIVITY_MAX
};

/*
 * ******************************************************************************
 * General port configuration agent routines
 * ****************************************************************************** */

/**
 *
 * @address_one: A SAS Address to be compared.
 * @address_two: A SAS Address to be compared.
 *
 * Compare the two SAS Address and if SAS Address One is greater than SAS
 * Address Two then return > 0 else if SAS Address One is less than SAS Address
 * Two return < 0 Otherwise they are the same return 0 A signed value of x > 0
 * > y where x is returned for Address One > Address Two y is returned for
 * Address One < Address Two 0 is returned ofr Address One = Address Two
 */
static s32 sci_sas_address_compare(
        struct sci_sas_address address_one,
        struct sci_sas_address address_two)
{
        if (address_one.high > address_two.high) {
                return 1;
        } else if (address_one.high < address_two.high) {
                return -1;
        } else if (address_one.low > address_two.low) {
                return 1;
        } else if (address_one.low < address_two.low) {
                return -1;
        }

        /* The two SAS Address must be identical */
        return 0;
}

/**
 *
 * @controller: The controller object used for the port search.
 * @phy: The phy object to match.
 *
 * This routine will find a matching port for the phy.  This means that the
 * port and phy both have the same broadcast sas address and same received sas
 * address. The port address or the NULL if there is no matching
 * port. port address if the port can be found to match the phy.
 * NULL if there is no matching port for the phy.
 */
static struct scic_sds_port *scic_sds_port_configuration_agent_find_port(
        struct scic_sds_controller *scic,
        struct scic_sds_phy *phy)
{
        u8 i;
        struct sci_sas_address port_sas_address;
        struct sci_sas_address port_attached_device_address;
        struct sci_sas_address phy_sas_address;
        struct sci_sas_address phy_attached_device_address;

        /*
         * Since this phy can be a member of a wide port check to see if one or
         * more phys match the sent and received SAS address as this phy in which
         * case it should participate in the same port.
         */
        scic_sds_phy_get_sas_address(phy, &phy_sas_address);
        scic_sds_phy_get_attached_sas_address(phy, &phy_attached_device_address);

        for (i = 0; i < scic->logical_port_entries; i++) {
                struct isci_host *ihost = scic_to_ihost(scic);
                struct scic_sds_port *sci_port = &ihost->ports[i].sci;

                scic_sds_port_get_sas_address(sci_port, &port_sas_address);
                scic_sds_port_get_attached_sas_address(sci_port, &port_attached_device_address);

                if (sci_sas_address_compare(port_sas_address, phy_sas_address) == 0 &&
                    sci_sas_address_compare(port_attached_device_address, phy_attached_device_address) == 0)
                        return sci_port;
        }

        return NULL;
}

/**
 *
 * @controller: This is the controller object that contains the port agent
 * @port_agent: This is the port configruation agent for the controller.
 *
 * This routine will validate the port configuration is correct for the SCU
 * hardware.  The SCU hardware allows for port configurations as follows. LP0
 * -> (PE0), (PE0, PE1), (PE0, PE1, PE2, PE3) LP1 -> (PE1) LP2 -> (PE2), (PE2,
 * PE3) LP3 -> (PE3) enum sci_status SCI_SUCCESS the port configuration is valid for
 * this port configuration agent. SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION
 * the port configuration is not valid for this port configuration agent.
 */
static enum sci_status scic_sds_port_configuration_agent_validate_ports(
        struct scic_sds_controller *controller,
        struct scic_sds_port_configuration_agent *port_agent)
{
        struct isci_host *ihost = scic_to_ihost(controller);
        struct sci_sas_address first_address;
        struct sci_sas_address second_address;

        /*
         * Sanity check the max ranges for all the phys the max index
         * is always equal to the port range index */
        if (port_agent->phy_valid_port_range[0].max_index != 0 ||
            port_agent->phy_valid_port_range[1].max_index != 1 ||
            port_agent->phy_valid_port_range[2].max_index != 2 ||
            port_agent->phy_valid_port_range[3].max_index != 3)
                return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;

        /*
         * This is a request to configure a single x4 port or at least attempt
         * to make all the phys into a single port */
        if (port_agent->phy_valid_port_range[0].min_index == 0 &&
            port_agent->phy_valid_port_range[1].min_index == 0 &&
            port_agent->phy_valid_port_range[2].min_index == 0 &&
            port_agent->phy_valid_port_range[3].min_index == 0)
                return SCI_SUCCESS;

        /*
         * This is a degenerate case where phy 1 and phy 2 are assigned
         * to the same port this is explicitly disallowed by the hardware
         * unless they are part of the same x4 port and this condition was
         * already checked above. */
        if (port_agent->phy_valid_port_range[2].min_index == 1) {
                return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
        }

        /*
         * PE0 and PE3 can never have the same SAS Address unless they
         * are part of the same x4 wide port and we have already checked
         * for this condition. */
        scic_sds_phy_get_sas_address(&ihost->phys[0].sci, &first_address);
        scic_sds_phy_get_sas_address(&ihost->phys[3].sci, &second_address);

        if (sci_sas_address_compare(first_address, second_address) == 0) {
                return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
        }

        /*
         * PE0 and PE1 are configured into a 2x1 ports make sure that the
         * SAS Address for PE0 and PE2 are different since they can not be
         * part of the same port. */
        if (port_agent->phy_valid_port_range[0].min_index == 0 &&
            port_agent->phy_valid_port_range[1].min_index == 1) {
                scic_sds_phy_get_sas_address(&ihost->phys[0].sci, &first_address);
                scic_sds_phy_get_sas_address(&ihost->phys[2].sci, &second_address);

                if (sci_sas_address_compare(first_address, second_address) == 0) {
                        return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
                }
        }

        /*
         * PE2 and PE3 are configured into a 2x1 ports make sure that the
         * SAS Address for PE1 and PE3 are different since they can not be
         * part of the same port. */
        if (port_agent->phy_valid_port_range[2].min_index == 2 &&
            port_agent->phy_valid_port_range[3].min_index == 3) {
                scic_sds_phy_get_sas_address(&ihost->phys[1].sci, &first_address);
                scic_sds_phy_get_sas_address(&ihost->phys[3].sci, &second_address);

                if (sci_sas_address_compare(first_address, second_address) == 0) {
                        return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
                }
        }

        return SCI_SUCCESS;
}

/*
 * ******************************************************************************
 * Manual port configuration agent routines
 * ****************************************************************************** */

/**
 *
 *
 * This routine will verify that all of the phys in the same port are using the
 * same SAS address.
 */
static enum sci_status scic_sds_mpc_agent_validate_phy_configuration(
        struct scic_sds_controller *controller,
        struct scic_sds_port_configuration_agent *port_agent)
{
        struct isci_host *ihost = scic_to_ihost(controller);
        u32 phy_mask;
        u32 assigned_phy_mask;
        struct sci_sas_address sas_address;
        struct sci_sas_address phy_assigned_address;
        u8 port_index;
        u8 phy_index;

        assigned_phy_mask = 0;
        sas_address.high = 0;
        sas_address.low = 0;

        for (port_index = 0; port_index < SCI_MAX_PORTS; port_index++) {
                phy_mask = controller->oem_parameters.sds1.ports[port_index].phy_mask;

                if (!phy_mask)
                        continue;
                /*
                 * Make sure that one or more of the phys were not already assinged to
                 * a different port. */
                if ((phy_mask & ~assigned_phy_mask) == 0) {
                        return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
                }

                /* Find the starting phy index for this round through the loop */
                for (phy_index = 0; phy_index < SCI_MAX_PHYS; phy_index++) {
                        if ((phy_mask & (1 << phy_index)) == 0)
                                continue;
                        scic_sds_phy_get_sas_address(&ihost->phys[phy_index].sci,
                                                     &sas_address);

                        /*
                         * The phy_index can be used as the starting point for the
                         * port range since the hardware starts all logical ports
                         * the same as the PE index. */
                        port_agent->phy_valid_port_range[phy_index].min_index = port_index;
                        port_agent->phy_valid_port_range[phy_index].max_index = phy_index;

                        if (phy_index != port_index) {
                                return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
                        }

                        break;
                }

                /*
                 * See how many additional phys are being added to this logical port.
                 * Note: We have not moved the current phy_index so we will actually
                 *       compare the startting phy with itself.
                 *       This is expected and required to add the phy to the port. */
                while (phy_index < SCI_MAX_PHYS) {
                        if ((phy_mask & (1 << phy_index)) == 0)
                                continue;
                        scic_sds_phy_get_sas_address(&ihost->phys[phy_index].sci,
                                                     &phy_assigned_address);

                        if (sci_sas_address_compare(sas_address, phy_assigned_address) != 0) {
                                /*
                                 * The phy mask specified that this phy is part of the same port
                                 * as the starting phy and it is not so fail this configuration */
                                return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
                        }

                        port_agent->phy_valid_port_range[phy_index].min_index = port_index;
                        port_agent->phy_valid_port_range[phy_index].max_index = phy_index;

                        scic_sds_port_add_phy(&ihost->ports[port_index].sci,
                                              &ihost->phys[phy_index].sci);

                        assigned_phy_mask |= (1 << phy_index);
                }

                phy_index++;
        }

        return scic_sds_port_configuration_agent_validate_ports(controller, port_agent);
}

/**
 *
 *
 * This timer routine is used to allow the SCI User to rediscover or change
 * device objects before a new series of link up notifications because a link
 * down has allowed a better port configuration.
 */
static void scic_sds_mpc_agent_timeout_handler(void *object)
{
        u8 index;
        struct scic_sds_controller *scic = object;
        struct isci_host *ihost = scic_to_ihost(scic);
        struct scic_sds_port_configuration_agent *port_agent = &scic->port_agent;
        u16 configure_phy_mask;

        port_agent->timer_pending = false;

        /* Find the mask of phys that are reported read but as yet unconfigured into a port */
        configure_phy_mask = ~port_agent->phy_configured_mask & port_agent->phy_ready_mask;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                struct scic_sds_phy *sci_phy = &ihost->phys[index].sci;

                if (configure_phy_mask & (1 << index)) {
                        port_agent->link_up_handler(scic, port_agent,
                                                    phy_get_non_dummy_port(sci_phy),
                                                    sci_phy);
                }
        }
}

/**
 *
 * @controller: This is the controller object that receives the link up
 *    notification.
 * @port: This is the port object associated with the phy.  If the is no
 *    associated port this is an NULL.
 * @phy: This is the phy object which has gone ready.
 *
 * This method handles the manual port configuration link up notifications.
 * Since all ports and phys are associate at initialization time we just turn
 * around and notifiy the port object that there is a link up.  If this PHY is
 * not associated with a port there is no action taken. Is it possible to get a
 * link up notification from a phy that has no assocoated port?
 */
static void scic_sds_mpc_agent_link_up(
        struct scic_sds_controller *controller,
        struct scic_sds_port_configuration_agent *port_agent,
        struct scic_sds_port *port,
        struct scic_sds_phy *phy)
{
        /*
         * If the port has an invalid handle then the phy was not assigned to
         * a port.  This is because the phy was not given the same SAS Address
         * as the other PHYs in the port. */
        if (port != NULL) {
                port_agent->phy_ready_mask |= (1 << scic_sds_phy_get_index(phy));

                scic_sds_port_link_up(port, phy);

                if ((port->active_phy_mask & (1 << scic_sds_phy_get_index(phy))) != 0) {
                        port_agent->phy_configured_mask |= (1 << scic_sds_phy_get_index(phy));
                }
        }
}

/**
 *
 * @controller: This is the controller object that receives the link down
 *    notification.
 * @port: This is the port object associated with the phy.  If the is no
 *    associated port this is an NULL.  The port is an invalid
 *    handle only if the phy was never port of this port.  This happens when
 *    the phy is not broadcasting the same SAS address as the other phys in the
 *    assigned port.
 * @phy: This is the phy object which has gone link down.
 *
 * This function handles the manual port configuration link down notifications.
 * Since all ports and phys are associated at initialization time we just turn
 * around and notifiy the port object of the link down event.  If this PHY is
 * not associated with a port there is no action taken. Is it possible to get a
 * link down notification from a phy that has no assocoated port?
 */
static void scic_sds_mpc_agent_link_down(
        struct scic_sds_controller *scic,
        struct scic_sds_port_configuration_agent *port_agent,
        struct scic_sds_port *sci_port,
        struct scic_sds_phy *sci_phy)
{
        if (sci_port != NULL) {
                /*
                 * If we can form a new port from the remainder of the phys
                 * then we want to start the timer to allow the SCI User to
                 * cleanup old devices and rediscover the port before
                 * rebuilding the port with the phys that remain in the ready
                 * state.
                 */
                port_agent->phy_ready_mask &=
                        ~(1 << scic_sds_phy_get_index(sci_phy));
                port_agent->phy_configured_mask &=
                        ~(1 << scic_sds_phy_get_index(sci_phy));

                /*
                 * Check to see if there are more phys waiting to be
                 * configured into a port. If there are allow the SCI User
                 * to tear down this port, if necessary, and then reconstruct
                 * the port after the timeout.
                 */
                if ((port_agent->phy_configured_mask == 0x0000) &&
                    (port_agent->phy_ready_mask != 0x0000) &&
                    !port_agent->timer_pending) {
                        port_agent->timer_pending = true;

                        isci_timer_start(port_agent->timer,
                                         SCIC_SDS_MPC_RECONFIGURATION_TIMEOUT);
                }

                scic_sds_port_link_down(sci_port, sci_phy);
        }
}

/*
 * ******************************************************************************
 * Automatic port configuration agent routines
 * ****************************************************************************** */

/**
 *
 *
 * This routine will verify that the phys are assigned a valid SAS address for
 * automatic port configuration mode.
 */
static enum sci_status scic_sds_apc_agent_validate_phy_configuration(
        struct scic_sds_controller *controller,
        struct scic_sds_port_configuration_agent *port_agent)
{
        u8 phy_index;
        u8 port_index;
        struct sci_sas_address sas_address;
        struct sci_sas_address phy_assigned_address;
        struct isci_host *ihost = scic_to_ihost(controller);

        phy_index = 0;

        while (phy_index < SCI_MAX_PHYS) {
                port_index = phy_index;

                /* Get the assigned SAS Address for the first PHY on the controller. */
                scic_sds_phy_get_sas_address(&ihost->phys[phy_index].sci,
                                            &sas_address);

                while (++phy_index < SCI_MAX_PHYS) {
                        scic_sds_phy_get_sas_address(&ihost->phys[phy_index].sci,
                                                     &phy_assigned_address);

                        /* Verify each of the SAS address are all the same for every PHY */
                        if (sci_sas_address_compare(sas_address, phy_assigned_address) == 0) {
                                port_agent->phy_valid_port_range[phy_index].min_index = port_index;
                                port_agent->phy_valid_port_range[phy_index].max_index = phy_index;
                        } else {
                                port_agent->phy_valid_port_range[phy_index].min_index = phy_index;
                                port_agent->phy_valid_port_range[phy_index].max_index = phy_index;
                                break;
                        }
                }
        }

        return scic_sds_port_configuration_agent_validate_ports(controller, port_agent);
}

/**
 *
 * @controller: This is the controller that to which the port agent is assigned.
 * @port_agent: This is the port agent that is requesting the timer start
 *    operation.
 * @phy: This is the phy that has caused the timer operation to be scheduled.
 *
 * This routine will restart the automatic port configuration timeout timer for
 * the next time period.  This could be caused by either a link down event or a
 * link up event where we can not yet tell to which port a phy belongs.
 */
static inline void scic_sds_apc_agent_start_timer(
        struct scic_sds_controller *scic,
        struct scic_sds_port_configuration_agent *port_agent,
        struct scic_sds_phy *sci_phy,
        u32 timeout)
{
        if (port_agent->timer_pending)
                isci_timer_stop(port_agent->timer);

        port_agent->timer_pending = true;

        isci_timer_start(port_agent->timer, timeout);
}

/**
 *
 * @controller: This is the controller object that receives the link up
 *    notification.
 * @phy: This is the phy object which has gone link up.
 *
 * This method handles the automatic port configuration for link up
 * notifications.
 */
static void scic_sds_apc_agent_configure_ports(
        struct scic_sds_controller *controller,
        struct scic_sds_port_configuration_agent *port_agent,
        struct scic_sds_phy *phy,
        bool start_timer)
{
        u8 port_index;
        enum sci_status status;
        struct scic_sds_port *port;
        enum SCIC_SDS_APC_ACTIVITY apc_activity = SCIC_SDS_APC_SKIP_PHY;
        struct isci_host *ihost = scic_to_ihost(controller);

        port = scic_sds_port_configuration_agent_find_port(controller, phy);

        if (port != NULL) {
                if (scic_sds_port_is_valid_phy_assignment(port, phy->phy_index))
                        apc_activity = SCIC_SDS_APC_ADD_PHY;
                else
                        apc_activity = SCIC_SDS_APC_SKIP_PHY;
        } else {
                /*
                 * There is no matching Port for this PHY so lets search through the
                 * Ports and see if we can add the PHY to its own port or maybe start
                 * the timer and wait to see if a wider port can be made.
                 *
                 * Note the break when we reach the condition of the port id == phy id */
                for (
                        port_index = port_agent->phy_valid_port_range[phy->phy_index].min_index;
                        port_index <= port_agent->phy_valid_port_range[phy->phy_index].max_index;
                        port_index++
                        ) {

                        port = &ihost->ports[port_index].sci;

                        /* First we must make sure that this PHY can be added to this Port. */
                        if (scic_sds_port_is_valid_phy_assignment(port, phy->phy_index)) {
                                /*
                                 * Port contains a PHY with a greater PHY ID than the current
                                 * PHY that has gone link up.  This phy can not be part of any
                                 * port so skip it and move on. */
                                if (port->active_phy_mask > (1 << phy->phy_index)) {
                                        apc_activity = SCIC_SDS_APC_SKIP_PHY;
                                        break;
                                }

                                /*
                                 * We have reached the end of our Port list and have not found
                                 * any reason why we should not either add the PHY to the port
                                 * or wait for more phys to become active. */
                                if (port->physical_port_index == phy->phy_index) {
                                        /*
                                         * The Port either has no active PHYs.
                                         * Consider that if the port had any active PHYs we would have
                                         * or active PHYs with
                                         * a lower PHY Id than this PHY. */
                                        if (apc_activity != SCIC_SDS_APC_START_TIMER) {
                                                apc_activity = SCIC_SDS_APC_ADD_PHY;
                                        }

                                        break;
                                }

                                /*
                                 * The current Port has no active PHYs and this PHY could be part
                                 * of this Port.  Since we dont know as yet setup to start the
                                 * timer and see if there is a better configuration. */
                                if (port->active_phy_mask == 0) {
                                        apc_activity = SCIC_SDS_APC_START_TIMER;
                                }
                        } else if (port->active_phy_mask != 0) {
                                /*
                                 * The Port has an active phy and the current Phy can not
                                 * participate in this port so skip the PHY and see if
                                 * there is a better configuration. */
                                apc_activity = SCIC_SDS_APC_SKIP_PHY;
                        }
                }
        }

        /*
         * Check to see if the start timer operations should instead map to an
         * add phy operation.  This is caused because we have been waiting to
         * add a phy to a port but could not becuase the automatic port
         * configuration engine had a choice of possible ports for the phy.
         * Since we have gone through a timeout we are going to restrict the
         * choice to the smallest possible port. */
        if (
                (start_timer == false)
                && (apc_activity == SCIC_SDS_APC_START_TIMER)
                ) {
                apc_activity = SCIC_SDS_APC_ADD_PHY;
        }

        switch (apc_activity) {
        case SCIC_SDS_APC_ADD_PHY:
                status = scic_sds_port_add_phy(port, phy);

                if (status == SCI_SUCCESS) {
                        port_agent->phy_configured_mask |= (1 << phy->phy_index);
                }
                break;

        case SCIC_SDS_APC_START_TIMER:
                scic_sds_apc_agent_start_timer(
                        controller, port_agent, phy, SCIC_SDS_APC_WAIT_LINK_UP_NOTIFICATION
                        );
                break;

        case SCIC_SDS_APC_SKIP_PHY:
        default:
                /* do nothing the PHY can not be made part of a port at this time. */
                break;
        }
}

/**
 * scic_sds_apc_agent_link_up - handle apc link up events
 * @scic: This is the controller object that receives the link up
 *    notification.
 * @sci_port: This is the port object associated with the phy.  If the is no
 *    associated port this is an NULL.
 * @sci_phy: This is the phy object which has gone link up.
 *
 * This method handles the automatic port configuration for link up
 * notifications. Is it possible to get a link down notification from a phy
 * that has no assocoated port?
 */
static void scic_sds_apc_agent_link_up(struct scic_sds_controller *scic,
                                       struct scic_sds_port_configuration_agent *port_agent,
                                       struct scic_sds_port *sci_port,
                                       struct scic_sds_phy *sci_phy)
{
        u8 phy_index  = sci_phy->phy_index;

        if (!sci_port) {
                /* the phy is not the part of this port */
                port_agent->phy_ready_mask |= 1 << phy_index;
                scic_sds_apc_agent_configure_ports(scic, port_agent, sci_phy, true);
        } else {
                /* the phy is already the part of the port */
                u32 port_state = sci_port->state_machine.current_state_id;

                /* if the PORT'S state is resetting then the link up is from
                 * port hard reset in this case, we need to tell the port
                 * that link up is recieved
                 */
                BUG_ON(port_state != SCI_BASE_PORT_STATE_RESETTING);
                port_agent->phy_ready_mask |= 1 << phy_index;
                scic_sds_port_link_up(sci_port, sci_phy);
        }
}

/**
 *
 * @controller: This is the controller object that receives the link down
 *    notification.
 * @port: This is the port object associated with the phy.  If the is no
 *    associated port this is an NULL.
 * @phy: This is the phy object which has gone link down.
 *
 * This method handles the automatic port configuration link down
 * notifications. not associated with a port there is no action taken. Is it
 * possible to get a link down notification from a phy that has no assocoated
 * port?
 */
static void scic_sds_apc_agent_link_down(
        struct scic_sds_controller *controller,
        struct scic_sds_port_configuration_agent *port_agent,
        struct scic_sds_port *port,
        struct scic_sds_phy *phy)
{
        port_agent->phy_ready_mask &= ~(1 << scic_sds_phy_get_index(phy));

        if (port != NULL) {
                if (port_agent->phy_configured_mask & (1 << phy->phy_index)) {
                        enum sci_status status;

                        status = scic_sds_port_remove_phy(port, phy);

                        if (status == SCI_SUCCESS) {
                                port_agent->phy_configured_mask &= ~(1 << phy->phy_index);
                        }
                }
        }
}

/* configure the phys into ports when the timer fires */
static void scic_sds_apc_agent_timeout_handler(void *object)
{
        u32 index;
        struct scic_sds_port_configuration_agent *port_agent;
        struct scic_sds_controller *scic = object;
        struct isci_host *ihost = scic_to_ihost(scic);
        u16 configure_phy_mask;

        port_agent = scic_sds_controller_get_port_configuration_agent(scic);

        port_agent->timer_pending = false;

        configure_phy_mask = ~port_agent->phy_configured_mask & port_agent->phy_ready_mask;

        if (!configure_phy_mask)
                return;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if ((configure_phy_mask & (1 << index)) == 0)
                        continue;

                scic_sds_apc_agent_configure_ports(scic, port_agent,
                                                   &ihost->phys[index].sci, false);
        }
}

/*
 * ******************************************************************************
 * Public port configuration agent routines
 * ****************************************************************************** */

/**
 *
 *
 * This method will construct the port configuration agent for operation. This
 * call is universal for both manual port configuration and automatic port
 * configuration modes.
 */
void scic_sds_port_configuration_agent_construct(
        struct scic_sds_port_configuration_agent *port_agent)
{
        u32 index;

        port_agent->phy_configured_mask = 0x00;
        port_agent->phy_ready_mask = 0x00;

        port_agent->link_up_handler = NULL;
        port_agent->link_down_handler = NULL;

        port_agent->timer_pending = false;
        port_agent->timer = NULL;

        for (index = 0; index < SCI_MAX_PORTS; index++) {
                port_agent->phy_valid_port_range[index].min_index = 0;
                port_agent->phy_valid_port_range[index].max_index = 0;
        }
}

enum sci_status scic_sds_port_configuration_agent_initialize(
        struct scic_sds_controller *scic,
        struct scic_sds_port_configuration_agent *port_agent)
{
        enum sci_status status = SCI_SUCCESS;
        enum scic_port_configuration_mode mode;
        struct isci_host *ihost = scic_to_ihost(scic);

        mode = scic->oem_parameters.sds1.controller.mode_type;

        if (mode == SCIC_PORT_MANUAL_CONFIGURATION_MODE) {
                status = scic_sds_mpc_agent_validate_phy_configuration(
                                scic, port_agent);

                port_agent->link_up_handler = scic_sds_mpc_agent_link_up;
                port_agent->link_down_handler = scic_sds_mpc_agent_link_down;

                port_agent->timer = isci_timer_create(
                                ihost,
                                scic,
                                scic_sds_mpc_agent_timeout_handler);
        } else {
                status = scic_sds_apc_agent_validate_phy_configuration(
                                scic, port_agent);

                port_agent->link_up_handler = scic_sds_apc_agent_link_up;
                port_agent->link_down_handler = scic_sds_apc_agent_link_down;

                port_agent->timer = isci_timer_create(
                                ihost,
                                scic,
                                scic_sds_apc_agent_timeout_handler);
        }

        /* Make sure we have actually gotten a timer */
        if ((status == SCI_SUCCESS) && (port_agent->timer == NULL)) {
                dev_err(scic_to_dev(scic),
                        "%s: Controller 0x%p automatic port configuration "
                        "agent could not get timer.\n",
                        __func__,
                        scic);

                status = SCI_FAILURE;
        }

        return status;
}