isci: workaround port task scheduler starvation issue

[deliverable/linux.git] / drivers / scsi / isci / core / scic_sds_port.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.
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 *     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
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "intel_sas.h"
#include "sci_base_port.h"
#include "scic_controller.h"
#include "scic_phy.h"
#include "scic_port.h"
#include "scic_sds_controller.h"
#include "scic_sds_phy.h"
#include "scic_sds_phy_registers.h"
#include "scic_sds_port.h"
#include "scic_sds_port_registers.h"
#include "scic_sds_remote_device.h"
#include "scic_sds_remote_node_context.h"
#include "scic_sds_request.h"
#include "sci_environment.h"
#include "scic_sds_controller_registers.h"


static void scic_sds_port_invalid_link_up(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *phy);
static void scic_sds_port_timeout_handler(
        void *port);
#define SCIC_SDS_PORT_MIN_TIMER_COUNT  (SCI_MAX_PORTS)
#define SCIC_SDS_PORT_MAX_TIMER_COUNT  (SCI_MAX_PORTS)

#define SCIC_SDS_PORT_HARD_RESET_TIMEOUT  (1000)
#define SCU_DUMMY_INDEX    (0xFFFF)

void sci_base_port_construct(
        struct sci_base_port *base_port,
        const struct sci_base_state *state_table)
{
        base_port->parent.private = NULL;
        sci_base_state_machine_construct(
                &base_port->state_machine,
                &base_port->parent,
                state_table,
                SCI_BASE_PORT_STATE_STOPPED
                );

        sci_base_state_machine_start(
                &base_port->state_machine
                );
}

/**
 *
 * @this_port: This is the port object to which the phy is being assigned.
 * @phy_index: This is the phy index that is being assigned to the port.
 *
 * This method will return a true value if the specified phy can be assigned to
 * this port The following is a list of phys for each port that are allowed: -
 * Port 0 - 3 2 1 0 - Port 1 -     1 - Port 2 - 3 2 - Port 3 - 3 This method
 * doesn't preclude all configurations.  It merely ensures that a phy is part
 * of the allowable set of phy identifiers for that port.  For example, one
 * could assign phy 3 to port 0 and no other phys.  Please refer to
 * scic_sds_port_is_phy_mask_valid() for information regarding whether the
 * phy_mask for a port can be supported. bool true if this is a valid phy
 * assignment for the port false if this is not a valid phy assignment for the
 * port
 */
bool scic_sds_port_is_valid_phy_assignment(
        struct scic_sds_port *this_port,
        u32 phy_index)
{
        /* Initialize to invalid value. */
        u32 existing_phy_index = SCI_MAX_PHYS;
        u32 index;

        if ((this_port->physical_port_index == 1) && (phy_index != 1)) {
                return false;
        }

        if (this_port->physical_port_index == 3 && phy_index != 3) {
                return false;
        }

        if (
                (this_port->physical_port_index == 2)
                && ((phy_index == 0) || (phy_index == 1))
                ) {
                return false;
        }

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if ((this_port->phy_table[index] != NULL)
                    && (index != phy_index)) {
                        existing_phy_index = index;
                }
        }

        /*
         * Ensure that all of the phys in the port are capable of
         * operating at the same maximum link rate. */
        if (
                (existing_phy_index < SCI_MAX_PHYS)
                && (this_port->owning_controller->user_parameters.sds1.phys[
                            phy_index].max_speed_generation !=
                    this_port->owning_controller->user_parameters.sds1.phys[
                            existing_phy_index].max_speed_generation)
                )
                return false;

        return true;
}

/**
 * This method requests a list (mask) of the phys contained in the supplied SAS
 *    port.
 * @this_port: a handle corresponding to the SAS port for which to return the
 *    phy mask.
 *
 * Return a bit mask indicating which phys are a part of this port. Each bit
 * corresponds to a phy identifier (e.g. bit 0 = phy id 0).
 */
u32 scic_sds_port_get_phys(struct scic_sds_port *this_port)
{
        u32 index;
        u32 mask;

        mask = 0;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if (this_port->phy_table[index] != NULL) {
                        mask |= (1 << index);
                }
        }

        return mask;
}

/**
 *
 * @this_port: This is the port object for which to determine if the phy mask
 *    can be supported.
 *
 * This method will return a true value if the port's phy mask can be supported
 * by the SCU. The following is a list of valid PHY mask configurations for
 * each port: - Port 0 - [[3  2] 1] 0 - Port 1 -        [1] - Port 2 - [[3] 2]
 * - Port 3 -  [3] This method returns a boolean indication specifying if the
 * phy mask can be supported. true if this is a valid phy assignment for the
 * port false if this is not a valid phy assignment for the port
 */
bool scic_sds_port_is_phy_mask_valid(
        struct scic_sds_port *this_port,
        u32 phy_mask)
{
        if (this_port->physical_port_index == 0) {
                if (((phy_mask & 0x0F) == 0x0F)
                    || ((phy_mask & 0x03) == 0x03)
                    || ((phy_mask & 0x01) == 0x01)
                    || (phy_mask == 0))
                        return true;
        } else if (this_port->physical_port_index == 1) {
                if (((phy_mask & 0x02) == 0x02)
                    || (phy_mask == 0))
                        return true;
        } else if (this_port->physical_port_index == 2) {
                if (((phy_mask & 0x0C) == 0x0C)
                    || ((phy_mask & 0x04) == 0x04)
                    || (phy_mask == 0))
                        return true;
        } else if (this_port->physical_port_index == 3) {
                if (((phy_mask & 0x08) == 0x08)
                    || (phy_mask == 0))
                        return true;
        }

        return false;
}

/**
 *
 * @this_port: This parameter specifies the port from which to return a
 *    connected phy.
 *
 * This method retrieves a currently active (i.e. connected) phy contained in
 * the port.  Currently, the lowest order phy that is connected is returned.
 * This method returns a pointer to a SCIS_SDS_PHY object. NULL This value is
 * returned if there are no currently active (i.e. connected to a remote end
 * point) phys contained in the port. All other values specify a struct scic_sds_phy
 * object that is active in the port.
 */
static struct scic_sds_phy *scic_sds_port_get_a_connected_phy(
        struct scic_sds_port *this_port
        ) {
        u32 index;
        struct scic_sds_phy *phy;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                /*
                 * Ensure that the phy is both part of the port and currently
                 * connected to the remote end-point. */
                phy = this_port->phy_table[index];
                if (
                        (phy != NULL)
                        && scic_sds_port_active_phy(this_port, phy)
                        ) {
                        return phy;
                }
        }

        return NULL;
}

/**
 * scic_sds_port_set_phy() -
 * @out]: port The port object to which the phy assignement is being made.
 * @out]: phy The phy which is being assigned to the port.
 *
 * This method attempts to make the assignment of the phy to the port. If
 * successful the phy is assigned to the ports phy table. bool true if the phy
 * assignment can be made. false if the phy assignement can not be made. This
 * is a functional test that only fails if the phy is currently assigned to a
 * different port.
 */
enum sci_status scic_sds_port_set_phy(
        struct scic_sds_port *port,
        struct scic_sds_phy *phy)
{
        /*
         * Check to see if we can add this phy to a port
         * that means that the phy is not part of a port and that the port does
         * not already have a phy assinged to the phy index. */
        if (
                (port->phy_table[phy->phy_index] == NULL)
                && (scic_sds_phy_get_port(phy) == NULL)
                && scic_sds_port_is_valid_phy_assignment(port, phy->phy_index)
                ) {
                /*
                 * Phy is being added in the stopped state so we are in MPC mode
                 * make logical port index = physical port index */
                port->logical_port_index = port->physical_port_index;
                port->phy_table[phy->phy_index] = phy;
                scic_sds_phy_set_port(phy, port);

                return SCI_SUCCESS;
        }

        return SCI_FAILURE;
}

/**
 * scic_sds_port_clear_phy() -
 * @out]: port The port from which the phy is being cleared.
 * @out]: phy The phy being cleared from the port.
 *
 * This method will clear the phy assigned to this port.  This method fails if
 * this phy is not currently assinged to this port. bool true if the phy is
 * removed from the port. false if this phy is not assined to this port.
 */
enum sci_status scic_sds_port_clear_phy(
        struct scic_sds_port *port,
        struct scic_sds_phy *phy)
{
        /* Make sure that this phy is part of this port */
        if (
                (port->phy_table[phy->phy_index] == phy)
                && (scic_sds_phy_get_port(phy) == port)
                ) {
                /* Yep it is assigned to this port so remove it */
                scic_sds_phy_set_port(
                        phy,
                        &scic_sds_port_get_controller(port)->port_table[SCI_MAX_PORTS]
                        );

                port->phy_table[phy->phy_index] = NULL;

                return SCI_SUCCESS;
        }

        return SCI_FAILURE;
}

/**
 * scic_sds_port_add_phy() -
 * @this_port: This parameter specifies the port in which the phy will be added.
 * @the_phy: This parameter is the phy which is to be added to the port.
 *
 * This method will add a PHY to the selected port. This method returns an
 * enum sci_status. SCI_SUCCESS the phy has been added to the port. Any other status
 * is failre to add the phy to the port.
 */
enum sci_status scic_sds_port_add_phy(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        return this_port->state_handlers->parent.add_phy_handler(
                       &this_port->parent, &the_phy->parent);
}


/**
 * scic_sds_port_remove_phy() -
 * @this_port: This parameter specifies the port in which the phy will be added.
 * @the_phy: This parameter is the phy which is to be added to the port.
 *
 * This method will remove the PHY from the selected PORT. This method returns
 * an enum sci_status. SCI_SUCCESS the phy has been removed from the port. Any other
 * status is failre to add the phy to the port.
 */
enum sci_status scic_sds_port_remove_phy(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        return this_port->state_handlers->parent.remove_phy_handler(
                       &this_port->parent, &the_phy->parent);
}

/**
 * This method requests the SAS address for the supplied SAS port from the SCI
 *    implementation.
 * @this_port: a handle corresponding to the SAS port for which to return the
 *    SAS address.
 * @sas_address: This parameter specifies a pointer to a SAS address structure
 *    into which the core will copy the SAS address for the port.
 *
 */
void scic_sds_port_get_sas_address(
        struct scic_sds_port *this_port,
        struct sci_sas_address *sas_address)
{
        u32 index;

        sas_address->high = 0;
        sas_address->low  = 0;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if (this_port->phy_table[index] != NULL) {
                        scic_sds_phy_get_sas_address(this_port->phy_table[index], sas_address);
                }
        }
}

/**
 * This method will indicate which protocols are supported by this port.
 * @this_port: a handle corresponding to the SAS port for which to return the
 *    supported protocols.
 * @protocols: This parameter specifies a pointer to an IAF protocol field
 *    structure into which the core will copy the protocol values for the port.
 *     The values are returned as part of a bit mask in order to allow for
 *    multi-protocol support.
 *
 */
static void scic_sds_port_get_protocols(
        struct scic_sds_port *this_port,
        struct sci_sas_identify_address_frame_protocols *protocols)
{
        u8 index;

        protocols->u.all = 0;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if (this_port->phy_table[index] != NULL) {
                        scic_sds_phy_get_protocols(this_port->phy_table[index], protocols);
                }
        }
}

/**
 * This method requests the SAS address for the device directly attached to
 *    this SAS port.
 * @this_port: a handle corresponding to the SAS port for which to return the
 *    SAS address.
 * @sas_address: This parameter specifies a pointer to a SAS address structure
 *    into which the core will copy the SAS address for the device directly
 *    attached to the port.
 *
 */
void scic_sds_port_get_attached_sas_address(
        struct scic_sds_port *this_port,
        struct sci_sas_address *sas_address)
{
        struct sci_sas_identify_address_frame_protocols protocols;
        struct scic_sds_phy *phy;

        /*
         * Ensure that the phy is both part of the port and currently
         * connected to the remote end-point. */
        phy = scic_sds_port_get_a_connected_phy(this_port);
        if (phy != NULL) {
                scic_sds_phy_get_attached_phy_protocols(phy, &protocols);

                if (!protocols.u.bits.stp_target) {
                        scic_sds_phy_get_attached_sas_address(phy, sas_address);
                } else {
                        scic_sds_phy_get_sas_address(phy, sas_address);
                        sas_address->low += phy->phy_index;
                }
        } else {
                sas_address->high = 0;
                sas_address->low  = 0;
        }
}

/**
 * This method will indicate which protocols are supported by this remote
 *    device.
 * @this_port: a handle corresponding to the SAS port for which to return the
 *    supported protocols.
 * @protocols: This parameter specifies a pointer to an IAF protocol field
 *    structure into which the core will copy the protocol values for the port.
 *     The values are returned as part of a bit mask in order to allow for
 *    multi-protocol support.
 *
 */
void scic_sds_port_get_attached_protocols(
        struct scic_sds_port *this_port,
        struct sci_sas_identify_address_frame_protocols *protocols)
{
        struct scic_sds_phy *phy;

        /*
         * Ensure that the phy is both part of the port and currently
         * connected to the remote end-point. */
        phy = scic_sds_port_get_a_connected_phy(this_port);
        if (phy != NULL)
                scic_sds_phy_get_attached_phy_protocols(phy, protocols);
        else
                protocols->u.all = 0;
}

/**
 * scic_sds_port_construct_dummy_rnc() - create dummy rnc for si workaround
 *
 * @sci_port: logical port on which we need to create the remote node context
 * @rni: remote node index for this remote node context.
 *
 * This routine will construct a dummy remote node context data structure
 * This structure will be posted to the hardware to work around a scheduler
 * error in the hardware.
 */
void scic_sds_port_construct_dummy_rnc(struct scic_sds_port *sci_port, u16 rni)
{
        union scu_remote_node_context *rnc;

        rnc = &sci_port->owning_controller->remote_node_context_table[rni];

        memset(rnc, 0, sizeof(union scu_remote_node_context));

        rnc->ssp.remote_sas_address_hi = 0;
        rnc->ssp.remote_sas_address_lo = 0;

        rnc->ssp.remote_node_index = rni;
        rnc->ssp.remote_node_port_width = 1;
        rnc->ssp.logical_port_index = sci_port->physical_port_index;

        rnc->ssp.nexus_loss_timer_enable = false;
        rnc->ssp.check_bit = false;
        rnc->ssp.is_valid = true;
        rnc->ssp.is_remote_node_context = true;
        rnc->ssp.function_number = 0;
        rnc->ssp.arbitration_wait_time = 0;
}

/**
 * scic_sds_port_construct_dummy_task() - create dummy task for si workaround
 * @sci_port The logical port on which we need to create the
 *            remote node context.
 *            context.
 * @tci The remote node index for this remote node context.
 *
 * This routine will construct a dummy task context data structure.  This
 * structure will be posted to the hardwre to work around a scheduler error
 * in the hardware.
 *
 */
void scic_sds_port_construct_dummy_task(struct scic_sds_port *sci_port, u16 tci)
{
        struct scu_task_context *task_context;

        task_context = scic_sds_controller_get_task_context_buffer(sci_port->owning_controller, tci);

        memset(task_context, 0, sizeof(struct scu_task_context));

        task_context->abort = 0;
        task_context->priority = 0;
        task_context->initiator_request = 1;
        task_context->connection_rate = 1;
        task_context->protocol_engine_index = 0;
        task_context->logical_port_index = sci_port->physical_port_index;
        task_context->protocol_type = SCU_TASK_CONTEXT_PROTOCOL_SSP;
        task_context->task_index = scic_sds_io_tag_get_index(tci);
        task_context->valid = SCU_TASK_CONTEXT_VALID;
        task_context->context_type = SCU_TASK_CONTEXT_TYPE;

        task_context->remote_node_index = sci_port->reserved_rni;
        task_context->command_code = 0;

        task_context->link_layer_control = 0;
        task_context->do_not_dma_ssp_good_response = 1;
        task_context->strict_ordering = 0;
        task_context->control_frame = 0;
        task_context->timeout_enable = 0;
        task_context->block_guard_enable = 0;

        task_context->address_modifier = 0;

        task_context->task_phase = 0x01;
}

void scic_sds_port_destroy_dummy_resources(struct scic_sds_port *sci_port)
{
        struct scic_sds_controller *scic = sci_port->owning_controller;

        if (sci_port->reserved_tci != SCU_DUMMY_INDEX)
                scic_controller_free_io_tag(scic, sci_port->reserved_tci);

        if (sci_port->reserved_rni != SCU_DUMMY_INDEX)
                scic_sds_remote_node_table_release_remote_node_index(&scic->available_remote_nodes,
                                                                     1, sci_port->reserved_rni);

        sci_port->reserved_rni = SCU_DUMMY_INDEX;
        sci_port->reserved_tci = SCU_DUMMY_INDEX;
}

void scic_sds_port_construct(struct scic_sds_port *sci_port, u8 port_index,
                             struct scic_sds_controller *scic)
{
        u32 index;

        sci_base_port_construct(&sci_port->parent, scic_sds_port_state_table);

        sci_base_state_machine_construct(
                scic_sds_port_get_ready_substate_machine(sci_port),
                &sci_port->parent.parent,
                scic_sds_port_ready_substate_table,
                SCIC_SDS_PORT_READY_SUBSTATE_WAITING
                );

        sci_port->logical_port_index  = SCIC_SDS_DUMMY_PORT;
        sci_port->physical_port_index = port_index;
        sci_port->active_phy_mask     = 0;

        sci_port->owning_controller = scic;

        sci_port->started_request_count = 0;
        sci_port->assigned_device_count = 0;

        sci_port->reserved_rni = SCU_DUMMY_INDEX;
        sci_port->reserved_tci = SCU_DUMMY_INDEX;

        sci_port->timer_handle = NULL;

        sci_port->port_task_scheduler_registers = NULL;

        for (index = 0; index < SCI_MAX_PHYS; index++)
                sci_port->phy_table[index] = NULL;
}

/**
 * This method performs initialization of the supplied port. Initialization
 *    includes: - state machine initialization - member variable initialization
 *    - configuring the phy_mask
 * @this_port:
 * @transport_layer_registers:
 * @port_task_scheduler_registers:
 * @port_configuration_regsiter:
 *
 * enum sci_status SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION This value is returned
 * if the phy being added to the port
 */
enum sci_status scic_sds_port_initialize(
        struct scic_sds_port *this_port,
        void __iomem *port_task_scheduler_registers,
        void __iomem *port_configuration_regsiter,
        void __iomem *viit_registers)
{
        this_port->port_task_scheduler_registers  = port_task_scheduler_registers;
        this_port->port_pe_configuration_register = port_configuration_regsiter;
        this_port->viit_registers                 = viit_registers;

        /*
         * If this is not the dummy port make the assignment of
         * the timer and start the state machine */
        if (this_port->physical_port_index != SCI_MAX_PORTS) {
                /* / @todo should we create the timer at create time? */
                this_port->timer_handle = isci_event_timer_create(
                        scic_sds_port_get_controller(this_port),
                        scic_sds_port_timeout_handler,
                        this_port
                        );

        } else {
                /*
                 * Force the dummy port into a condition where it rejects all requests
                 * as its in an invalid state for any operation.
                 * / @todo should we set a set of specical handlers for the dummy port? */
                scic_sds_port_set_base_state_handlers(
                        this_port, SCI_BASE_PORT_STATE_STOPPED
                        );
        }

        return SCI_SUCCESS;
}

/**
 *
 * @this_port: This is the struct scic_sds_port object for which has a phy that has
 *    gone link up.
 * @the_phy: This is the struct scic_sds_phy object that has gone link up.
 * @do_notify_user: This parameter specifies whether to inform the user (via
 *    scic_cb_port_link_up()) as to the fact that a new phy as become ready.
 *
 * This method is the a general link up handler for the struct scic_sds_port object.
 * This function will determine if this struct scic_sds_phy can be assigned to this
 * struct scic_sds_port object. If the struct scic_sds_phy object can is not a valid PHY for
 * this port then the function will notify the SCIC_USER. A PHY can only be
 * part of a port if it's attached SAS ADDRESS is the same as all other PHYs in
 * the same port. none
 */
void scic_sds_port_general_link_up_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy,
        bool do_notify_user)
{
        struct sci_sas_address port_sas_address;
        struct sci_sas_address phy_sas_address;

        scic_sds_port_get_attached_sas_address(this_port, &port_sas_address);
        scic_sds_phy_get_attached_sas_address(the_phy, &phy_sas_address);

        /*
         * If the SAS address of the new phy matches the SAS address of
         * other phys in the port OR this is the first phy in the port,
         * then activate the phy and allow it to be used for operations
         * in this port. */
        if (
                (
                        (phy_sas_address.high == port_sas_address.high)
                        && (phy_sas_address.low  == port_sas_address.low)
                )
                || (this_port->active_phy_mask == 0)
                ) {
                scic_sds_port_activate_phy(this_port, the_phy, do_notify_user);

                if (this_port->parent.state_machine.current_state_id
                    == SCI_BASE_PORT_STATE_RESETTING) {
                        sci_base_state_machine_change_state(
                                &this_port->parent.state_machine, SCI_BASE_PORT_STATE_READY
                                );
                }
        } else {
                scic_sds_port_invalid_link_up(this_port, the_phy);
        }
}

enum sci_status scic_port_stop(struct scic_sds_port *port)
{
        return port->state_handlers->parent.stop_handler(&port->parent);
}

enum sci_status scic_port_get_properties(
        struct scic_sds_port *port,
        struct scic_port_properties *prop)
{
        if ((port == NULL) ||
            (port->logical_port_index == SCIC_SDS_DUMMY_PORT))
                return SCI_FAILURE_INVALID_PORT;

        prop->index    = port->logical_port_index;
        prop->phy_mask = scic_sds_port_get_phys(port);
        scic_sds_port_get_sas_address(port, &prop->local.sas_address);
        scic_sds_port_get_protocols(port, &prop->local.protocols);
        scic_sds_port_get_attached_sas_address(port, &prop->remote.sas_address);
        scic_sds_port_get_attached_protocols(port, &prop->remote.protocols);

        return SCI_SUCCESS;
}


enum sci_status scic_port_hard_reset(
        struct scic_sds_port *port,
        u32 reset_timeout)
{
        return port->state_handlers->parent.reset_handler(
                       &port->parent, reset_timeout);
}

/**
 * This method assigns the direct attached device ID for this port.
 *
 * @param[in] this_port The port for which the direct attached device id is to
 *       be assigned.
 * @param[in] device_id The direct attached device ID to assign to the port.
 *       This will be the RNi for the device
 */
void scic_sds_port_setup_transports(
        struct scic_sds_port *this_port,
        u32 device_id)
{
        u8 index;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if (this_port->active_phy_mask & (1 << index))
                        scic_sds_phy_setup_transport(this_port->phy_table[index], device_id);
        }
}

/**
 *
 * @this_port: This is the port on which the phy should be enabled.
 * @the_phy: This is the specific phy which to enable.
 * @do_notify_user: This parameter specifies whether to inform the user (via
 *    scic_cb_port_link_up()) as to the fact that a new phy as become ready.
 *
 * This method will activate the phy in the port. Activation includes: - adding
 * the phy to the port - enabling the Protocol Engine in the silicon. -
 * notifying the user that the link is up. none
 */
void scic_sds_port_activate_phy(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy,
        bool do_notify_user)
{
        struct scic_sds_controller *controller;
        struct sci_sas_identify_address_frame_protocols protocols;

        controller = scic_sds_port_get_controller(this_port);
        scic_sds_phy_get_attached_phy_protocols(the_phy, &protocols);

        /* If this is sata port then the phy has already been resumed */
        if (!protocols.u.bits.stp_target) {
                scic_sds_phy_resume(the_phy);
        }

        this_port->active_phy_mask |= 1 << the_phy->phy_index;

        scic_sds_controller_clear_invalid_phy(controller, the_phy);

        if (do_notify_user == true)
                isci_event_port_link_up(this_port->owning_controller,
                                        this_port,
                                        the_phy);
}

/**
 *
 * @this_port: This is the port on which the phy should be deactivated.
 * @the_phy: This is the specific phy that is no longer active in the port.
 * @do_notify_user: This parameter specifies whether to inform the user (via
 *    isci_event_port_link_down()) as to the fact that a new phy as become
 *    ready.
 *
 * This method will deactivate the supplied phy in the port. none
 */
void scic_sds_port_deactivate_phy(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy,
        bool do_notify_user)
{
        this_port->active_phy_mask &= ~(1 << the_phy->phy_index);

        the_phy->max_negotiated_speed = SCI_SAS_NO_LINK_RATE;

        /* Re-assign the phy back to the LP as if it were a narrow port */
        SCU_PCSPExCR_WRITE(this_port, the_phy->phy_index, the_phy->phy_index);

        if (do_notify_user == true)
                isci_event_port_link_down(this_port->owning_controller,
                                          this_port,
                                          the_phy);
}

/**
 *
 * @this_port: This is the port on which the phy should be disabled.
 * @the_phy: This is the specific phy which to disabled.
 *
 * This method will disable the phy and report that the phy is not valid for
 * this port object. None
 */
static void scic_sds_port_invalid_link_up(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        struct scic_sds_controller *controller = scic_sds_port_get_controller(this_port);

        /*
         * Check to see if we have alreay reported this link as bad and if not go
         * ahead and tell the SCI_USER that we have discovered an invalid link. */
        if ((controller->invalid_phy_mask & (1 << the_phy->phy_index)) == 0) {
                scic_sds_controller_set_invalid_phy(controller, the_phy);

                isci_event_port_invalid_link_up(controller, this_port, the_phy);
        }
}

/**
 * This method returns false if the port only has a single phy object assigned.
 *     If there are no phys or more than one phy then the method will return
 *    true.
 * @this_port: The port for which the wide port condition is to be checked.
 *
 * bool true Is returned if this is a wide ported port. false Is returned if
 * this is a narrow port.
 */
static bool scic_sds_port_is_wide(struct scic_sds_port *this_port)
{
        u32 index;
        u32 phy_count = 0;

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if (this_port->phy_table[index] != NULL) {
                        phy_count++;
                }
        }

        return phy_count != 1;
}

/**
 * This method is called by the PHY object when the link is detected. if the
 *    port wants the PHY to continue on to the link up state then the port
 *    layer must return true.  If the port object returns false the phy object
 *    must halt its attempt to go link up.
 * @this_port: The port associated with the phy object.
 * @the_phy: The phy object that is trying to go link up.
 *
 * true if the phy object can continue to the link up condition. true Is
 * returned if this phy can continue to the ready state. false Is returned if
 * can not continue on to the ready state. This notification is in place for
 * wide ports and direct attached phys.  Since there are no wide ported SATA
 * devices this could become an invalid port configuration.
 */
bool scic_sds_port_link_detected(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        struct sci_sas_identify_address_frame_protocols protocols;

        scic_sds_phy_get_attached_phy_protocols(the_phy, &protocols);

        if (
                (this_port->logical_port_index != SCIC_SDS_DUMMY_PORT)
                && (protocols.u.bits.stp_target)
                && scic_sds_port_is_wide(this_port)
                ) {
                scic_sds_port_invalid_link_up(this_port, the_phy);

                return false;
        }

        return true;
}

/**
 * This method is the entry point for the phy to inform the port that it is now
 *    in a ready state
 * @this_port:
 *
 *
 */
void scic_sds_port_link_up(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        the_phy->is_in_link_training = false;

        this_port->state_handlers->link_up_handler(this_port, the_phy);
}

/**
 * This method is the entry point for the phy to inform the port that it is no
 *    longer in a ready state
 * @this_port:
 *
 *
 */
void scic_sds_port_link_down(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        this_port->state_handlers->link_down_handler(this_port, the_phy);
}

/**
 * This method is called to start an IO request on this port.
 * @this_port:
 * @the_device:
 * @the_io_request:
 *
 * enum sci_status
 */
enum sci_status scic_sds_port_start_io(
        struct scic_sds_port *this_port,
        struct scic_sds_remote_device *the_device,
        struct scic_sds_request *the_io_request)
{
        return this_port->state_handlers->start_io_handler(
                       this_port, the_device, the_io_request);
}

/**
 * This method is called to complete an IO request to the port.
 * @this_port:
 * @the_device:
 * @the_io_request:
 *
 * enum sci_status
 */
enum sci_status scic_sds_port_complete_io(
        struct scic_sds_port *this_port,
        struct scic_sds_remote_device *the_device,
        struct scic_sds_request *the_io_request)
{
        return this_port->state_handlers->complete_io_handler(
                       this_port, the_device, the_io_request);
}

/**
 * This method is provided to timeout requests for port operations. Mostly its
 *    for the port reset operation.
 *
 *
 */
static void scic_sds_port_timeout_handler(void *port)
{
        struct scic_sds_port *this_port = port;
        u32 current_state;

        current_state = sci_base_state_machine_get_state(
                &this_port->parent.state_machine);

        if (current_state == SCI_BASE_PORT_STATE_RESETTING) {
                /*
                 * if the port is still in the resetting state then the timeout fired
                 * before the reset completed. */
                sci_base_state_machine_change_state(
                        &this_port->parent.state_machine,
                        SCI_BASE_PORT_STATE_FAILED
                        );
        } else if (current_state == SCI_BASE_PORT_STATE_STOPPED) {
                /*
                 * if the port is stopped then the start request failed
                 * In this case stay in the stopped state. */
                dev_err(sciport_to_dev(this_port),
                        "%s: SCIC Port 0x%p failed to stop before tiemout.\n",
                        __func__,
                        this_port);
        } else if (current_state == SCI_BASE_PORT_STATE_STOPPING) {
                /* if the port is still stopping then the stop has not completed */
                isci_event_port_stop_complete(
                        scic_sds_port_get_controller(this_port),
                        port,
                        SCI_FAILURE_TIMEOUT
                        );
        } else {
                /*
                 * The port is in the ready state and we have a timer reporting a timeout
                 * this should not happen. */
                dev_err(sciport_to_dev(this_port),
                        "%s: SCIC Port 0x%p is processing a timeout operation "
                        "in state %d.\n",
                        __func__,
                        this_port,
                        current_state);
        }
}

/* --------------------------------------------------------------------------- */

/**
 * This function updates the hardwares VIIT entry for this port.
 *
 *
 */
void scic_sds_port_update_viit_entry(struct scic_sds_port *this_port)
{
        struct sci_sas_address sas_address;

        scic_sds_port_get_sas_address(this_port, &sas_address);

        scu_port_viit_register_write(
                this_port, initiator_sas_address_hi, sas_address.high);

        scu_port_viit_register_write(
                this_port, initiator_sas_address_lo, sas_address.low);

        /* This value get cleared just in case its not already cleared */
        scu_port_viit_register_write(
                this_port, reserved, 0);

        /* We are required to update the status register last */
        scu_port_viit_register_write(
                this_port, status, (
                        SCU_VIIT_ENTRY_ID_VIIT
                        | SCU_VIIT_IPPT_INITIATOR
                        | ((1 << this_port->physical_port_index) << SCU_VIIT_ENTRY_LPVIE_SHIFT)
                        | SCU_VIIT_STATUS_ALL_VALID
                        )
                );
}

/**
 * This method returns the maximum allowed speed for data transfers on this
 *    port.  This maximum allowed speed evaluates to the maximum speed of the
 *    slowest phy in the port.
 * @this_port: This parameter specifies the port for which to retrieve the
 *    maximum allowed speed.
 *
 * This method returns the maximum negotiated speed of the slowest phy in the
 * port.
 */
enum sci_sas_link_rate scic_sds_port_get_max_allowed_speed(
        struct scic_sds_port *this_port)
{
        u16 index             = 0;
        enum sci_sas_link_rate max_allowed_speed = SCI_SAS_600_GB;
        struct scic_sds_phy *phy               = NULL;

        /*
         * Loop through all of the phys in this port and find the phy with the
         * lowest maximum link rate. */
        for (index = 0; index < SCI_MAX_PHYS; index++) {
                phy = this_port->phy_table[index];
                if (
                        (phy != NULL)
                        && (scic_sds_port_active_phy(this_port, phy) == true)
                        && (phy->max_negotiated_speed < max_allowed_speed)
                        )
                        max_allowed_speed = phy->max_negotiated_speed;
        }

        return max_allowed_speed;
}


/**
 * This method passes the event to core user.
 * @this_port: The port that a BCN happens.
 * @this_phy: The phy that receives BCN.
 *
 */
void scic_sds_port_broadcast_change_received(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *this_phy)
{
        /* notify the user. */
        isci_event_port_bc_change_primitive_received(
                this_port->owning_controller, this_port, this_phy
                );
}


/**
 * This API methhod enables the broadcast change notification from underneath
 *    hardware.
 * @this_port: The port that a BCN had been disabled from.
 *
 */
void scic_port_enable_broadcast_change_notification(
        struct scic_sds_port *port)
{
        struct scic_sds_phy *phy;
        u32 register_value;
        u8 index;

        /* Loop through all of the phys to enable BCN. */
        for (index = 0; index < SCI_MAX_PHYS; index++) {
                phy = port->phy_table[index];
                if (phy != NULL) {
                        register_value = SCU_SAS_LLCTL_READ(phy);

                        /* clear the bit by writing 1. */
                        SCU_SAS_LLCTL_WRITE(phy, register_value);
                }
        }
}

/*
 * ****************************************************************************
 * *  READY SUBSTATE HANDLERS
 * **************************************************************************** */

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This method is the general ready state stop handler for the struct scic_sds_port
 * object.  This function will transition the ready substate machine to its
 * final state. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_ready_substate_stop_handler(
        struct sci_base_port *port)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        sci_base_state_machine_change_state(
                &this_port->parent.state_machine,
                SCI_BASE_PORT_STATE_STOPPING
                );

        return SCI_SUCCESS;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @device: This is the struct sci_base_remote_device object which is not used in this
 *    function.
 * @io_request: This is the struct sci_base_request object which is not used in this
 *    function.
 *
 * This method is the general ready substate complete io handler for the
 * struct scic_sds_port object.  This function decrments the outstanding request count
 * for this port object. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_ready_substate_complete_io_handler(
        struct scic_sds_port *port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        scic_sds_port_decrement_request_count(this_port);

        return SCI_SUCCESS;
}

static enum sci_status scic_sds_port_ready_substate_add_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *this_phy  = (struct scic_sds_phy *)phy;
        enum sci_status status;

        status = scic_sds_port_set_phy(this_port, this_phy);

        if (status == SCI_SUCCESS) {
                scic_sds_port_general_link_up_handler(this_port, this_phy, true);

                this_port->not_ready_reason = SCIC_PORT_NOT_READY_RECONFIGURING;

                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING
                        );
        }

        return status;
}


static enum sci_status scic_sds_port_ready_substate_remove_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *this_phy  = (struct scic_sds_phy *)phy;
        enum sci_status status;

        status = scic_sds_port_clear_phy(this_port, this_phy);

        if (status == SCI_SUCCESS) {
                scic_sds_port_deactivate_phy(this_port, this_phy, true);

                this_port->not_ready_reason = SCIC_PORT_NOT_READY_RECONFIGURING;

                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING
                        );
        }

        return status;
}

/*
 * ****************************************************************************
 * *  READY SUBSTATE WAITING HANDLERS
 * **************************************************************************** */

/**
 *
 * @this_port: This is the struct scic_sds_port object that which has a phy that has
 *    gone link up.
 * @the_phy: This is the struct scic_sds_phy object that has gone link up.
 *
 * This method is the ready waiting substate link up handler for the
 * struct scic_sds_port object.  This methos will report the link up condition for
 * this port and will transition to the ready operational substate. none
 */
static void scic_sds_port_ready_waiting_substate_link_up_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        /*
         * Since this is the first phy going link up for the port we can just enable
         * it and continue. */
        scic_sds_port_activate_phy(this_port, the_phy, true);

        sci_base_state_machine_change_state(
                &this_port->ready_substate_machine,
                SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL
                );
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @device: This is the struct sci_base_remote_device object which is not used in this
 *    request.
 * @io_request: This is the struct sci_base_request object which is not used in this
 *    function.
 *
 * This method is the ready waiting substate start io handler for the
 * struct scic_sds_port object. The port object can not accept new requests so the
 * request is failed. enum sci_status SCI_FAILURE_INVALID_STATE
 */
static enum sci_status scic_sds_port_ready_waiting_substate_start_io_handler(
        struct scic_sds_port *port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        return SCI_FAILURE_INVALID_STATE;
}

/*
 * ****************************************************************************
 * *  READY SUBSTATE OPERATIONAL HANDLERS
 * **************************************************************************** */

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @timeout: This is the timeout for the reset request to complete.
 *
 * This method will casue the port to reset. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_ready_operational_substate_reset_handler(
        struct sci_base_port *port,
        u32 timeout)
{
        enum sci_status status = SCI_FAILURE_INVALID_PHY;
        u32 phy_index;
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *selected_phy = NULL;


        /* Select a phy on which we can send the hard reset request. */
        for (
                phy_index = 0;
                (phy_index < SCI_MAX_PHYS)
                && (selected_phy == NULL);
                phy_index++
                ) {
                selected_phy = this_port->phy_table[phy_index];

                if (
                        (selected_phy != NULL)
                        && !scic_sds_port_active_phy(this_port, selected_phy)
                        ) {
                        /* We found a phy but it is not ready select different phy */
                        selected_phy = NULL;
                }
        }

        /* If we have a phy then go ahead and start the reset procedure */
        if (selected_phy != NULL) {
                status = scic_sds_phy_reset(selected_phy);

                if (status == SCI_SUCCESS) {
                        isci_event_timer_start(
                                scic_sds_port_get_controller(this_port),
                                this_port->timer_handle,
                                timeout
                                );

                        this_port->not_ready_reason = SCIC_PORT_NOT_READY_HARD_RESET_REQUESTED;

                        sci_base_state_machine_change_state(
                                &this_port->parent.state_machine,
                                SCI_BASE_PORT_STATE_RESETTING
                                );
                }
        }

        return status;
}

/**
 * scic_sds_port_ready_operational_substate_link_up_handler() -
 * @this_port: This is the struct scic_sds_port object that which has a phy that has
 *    gone link up.
 * @the_phy: This is the struct scic_sds_phy object that has gone link up.
 *
 * This method is the ready operational substate link up handler for the
 * struct scic_sds_port object. This function notifies the SCI User that the phy has
 * gone link up. none
 */
static void scic_sds_port_ready_operational_substate_link_up_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        scic_sds_port_general_link_up_handler(this_port, the_phy, true);
}

/**
 * scic_sds_port_ready_operational_substate_link_down_handler() -
 * @this_port: This is the struct scic_sds_port object that which has a phy that has
 *    gone link down.
 * @the_phy: This is the struct scic_sds_phy object that has gone link down.
 *
 * This method is the ready operational substate link down handler for the
 * struct scic_sds_port object. This function notifies the SCI User that the phy has
 * gone link down and if this is the last phy in the port the port will change
 * state to the ready waiting substate. none
 */
static void scic_sds_port_ready_operational_substate_link_down_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *the_phy)
{
        scic_sds_port_deactivate_phy(this_port, the_phy, true);

        /*
         * If there are no active phys left in the port, then transition
         * the port to the WAITING state until such time as a phy goes
         * link up. */
        if (this_port->active_phy_mask == 0) {
                sci_base_state_machine_change_state(
                        scic_sds_port_get_ready_substate_machine(this_port),
                        SCIC_SDS_PORT_READY_SUBSTATE_WAITING
                        );
        }
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @device: This is the struct sci_base_remote_device object which is not used in this
 *    function.
 * @io_request: This is the struct sci_base_request object which is not used in this
 *    function.
 *
 * This method is the ready operational substate start io handler for the
 * struct scic_sds_port object.  This function incremetns the outstanding request
 * count for this port object. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_ready_operational_substate_start_io_handler(
        struct scic_sds_port *port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        scic_sds_port_increment_request_count(this_port);

        return SCI_SUCCESS;
}

/*
 * ****************************************************************************
 * *  READY SUBSTATE OPERATIONAL HANDLERS
 * **************************************************************************** */

/**
 * scic_sds_port_ready_configuring_substate_add_phy_handler() -
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port add phy request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
static enum sci_status scic_sds_port_ready_configuring_substate_add_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *this_phy  = (struct scic_sds_phy *)phy;
        enum sci_status status;

        status = scic_sds_port_set_phy(this_port, this_phy);

        if (status == SCI_SUCCESS) {
                scic_sds_port_general_link_up_handler(this_port, this_phy, true);

                /*
                 * Re-enter the configuring state since this may be the last phy in
                 * the port. */
                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING
                        );
        }

        return status;
}

/**
 * scic_sds_port_ready_configuring_substate_remove_phy_handler() -
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port remove phy request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
static enum sci_status scic_sds_port_ready_configuring_substate_remove_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *this_phy  = (struct scic_sds_phy *)phy;
        enum sci_status status;

        status = scic_sds_port_clear_phy(this_port, this_phy);

        if (status == SCI_SUCCESS) {
                scic_sds_port_deactivate_phy(this_port, this_phy, true);

                /*
                 * Re-enter the configuring state since this may be the last phy in
                 * the port. */
                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING
                        );
        }

        return status;
}

/**
 * scic_sds_port_ready_configuring_substate_complete_io_handler() -
 * @port: This is the port that is being requested to complete the io request.
 * @device: This is the device on which the io is completing.
 *
 * This method will decrement the outstanding request count for this port. If
 * the request count goes to 0 then the port can be reprogrammed with its new
 * phy data.
 */
static enum sci_status scic_sds_port_ready_configuring_substate_complete_io_handler(
        struct scic_sds_port *port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        scic_sds_port_decrement_request_count(port);

        if (port->started_request_count == 0) {
                sci_base_state_machine_change_state(
                        &port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL
                        );
        }

        return SCI_SUCCESS;
}

/* --------------------------------------------------------------------------- */

struct scic_sds_port_state_handler
scic_sds_port_ready_substate_handler_table[SCIC_SDS_PORT_READY_MAX_SUBSTATES] =
{
        /* SCIC_SDS_PORT_READY_SUBSTATE_WAITING */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_ready_substate_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_ready_substate_add_phy_handler,
                        scic_sds_port_default_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_ready_waiting_substate_link_up_handler,
                scic_sds_port_default_link_down_handler,
                scic_sds_port_ready_waiting_substate_start_io_handler,
                scic_sds_port_ready_substate_complete_io_handler,
        },
        /* SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_ready_substate_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_ready_operational_substate_reset_handler,
                        scic_sds_port_ready_substate_add_phy_handler,
                        scic_sds_port_ready_substate_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_ready_operational_substate_link_up_handler,
                scic_sds_port_ready_operational_substate_link_down_handler,
                scic_sds_port_ready_operational_substate_start_io_handler,
                scic_sds_port_ready_substate_complete_io_handler
        },
        /* SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_ready_substate_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_ready_configuring_substate_add_phy_handler,
                        scic_sds_port_ready_configuring_substate_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_default_link_up_handler,
                scic_sds_port_default_link_down_handler,
                scic_sds_port_default_start_io_handler,
                scic_sds_port_ready_configuring_substate_complete_io_handler
        }
};


/**
 * scic_sds_port_set_ready_state_handlers() -
 *
 * This macro sets the port ready substate handlers.
 */
#define scic_sds_port_set_ready_state_handlers(port, state_id) \
        scic_sds_port_set_state_handlers(\
                port, &scic_sds_port_ready_substate_handler_table[(state_id)] \
                )

/*
 * ******************************************************************************
 * *  PORT STATE PRIVATE METHODS
 * ****************************************************************************** */

/**
 *
 * @this_port: This is the struct scic_sds_port object to suspend.
 *
 * This method will susped the port task scheduler for this port object. none
 */
static void scic_sds_port_suspend_port_task_scheduler(
        struct scic_sds_port *this_port)
{
        u32 pts_control_value;

        pts_control_value = scu_port_task_scheduler_read(this_port, control);

        pts_control_value |= SCU_PTSxCR_GEN_BIT(SUSPEND);

        scu_port_task_scheduler_write(this_port, control, pts_control_value);
}

/**
 * scic_sds_port_post_dummy_request() - post dummy/workaround request
 * @sci_port: port to post task
 *
 * Prevent the hardware scheduler from posting new requests to the front
 * of the scheduler queue causing a starvation problem for currently
 * ongoing requests.
 *
 */
void scic_sds_port_post_dummy_request(struct scic_sds_port *sci_port)
{
        u32 command;
        struct scu_task_context *task_context;
        struct scic_sds_controller *scic = sci_port->owning_controller;
        u16 tci = sci_port->reserved_tci;

        task_context = scic_sds_controller_get_task_context_buffer(scic, tci);

        task_context->abort = 0;

        command = SCU_CONTEXT_COMMAND_REQUEST_TYPE_POST_TC |
                  sci_port->physical_port_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT |
                  tci;

        scic_sds_controller_post_request(scic, command);
}

/**
 * This routine will abort the dummy request.  This will alow the hardware to
 * power down parts of the silicon to save power.
 *
 * @sci_port: The port on which the task must be aborted.
 *
 */
void scic_sds_port_abort_dummy_request(struct scic_sds_port *sci_port)
{
        struct scic_sds_controller *scic = sci_port->owning_controller;
        u16 tci = sci_port->reserved_tci;
        struct scu_task_context *tc;
        u32 command;

        tc = scic_sds_controller_get_task_context_buffer(scic, tci);

        tc->abort = 1;

        command = SCU_CONTEXT_COMMAND_REQUEST_POST_TC_ABORT |
                  sci_port->physical_port_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT |
                  tci;

        scic_sds_controller_post_request(scic, command);
}

/**
 *
 * @this_port: This is the struct scic_sds_port object to resume.
 *
 * This method will resume the port task scheduler for this port object. none
 */
static void scic_sds_port_resume_port_task_scheduler(
        struct scic_sds_port *this_port)
{
        u32 pts_control_value;

        pts_control_value = scu_port_task_scheduler_read(this_port, control);

        pts_control_value &= ~SCU_PTSxCR_GEN_BIT(SUSPEND);

        scu_port_task_scheduler_write(this_port, control, pts_control_value);
}

/*
 * ******************************************************************************
 * *  PORT READY SUBSTATE METHODS
 * ****************************************************************************** */

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCIC_SDS_PORT_READY_SUBSTATE_WAITING. This function checks the
 * port for any ready phys.  If there is at least one phy in a ready state then
 * the port transitions to the ready operational substate. none
 */
static void scic_sds_port_ready_substate_waiting_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_ready_state_handlers(
                this_port, SCIC_SDS_PORT_READY_SUBSTATE_WAITING
                );

        scic_sds_port_suspend_port_task_scheduler(this_port);

        /* Kill the dummy task for this port if it has not yet posted
         * the hardware will treat this as a NOP and just return abort
         * complete.
         */
        scic_sds_port_abort_dummy_request(this_port);

        this_port->not_ready_reason = SCIC_PORT_NOT_READY_NO_ACTIVE_PHYS;

        if (this_port->active_phy_mask != 0) {
                /* At least one of the phys on the port is ready */
                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL
                        );
        }
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL. This function sets
 * the state handlers for the port object, notifies the SCI User that the port
 * is ready, and resumes port operations. none
 */
static void scic_sds_port_ready_substate_operational_enter(
        struct sci_base_object *object)
{
        u32 index;
        struct scic_sds_port *this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_ready_state_handlers(
                this_port, SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL
                );

        isci_event_port_ready(
                scic_sds_port_get_controller(this_port), this_port
                );

        for (index = 0; index < SCI_MAX_PHYS; index++) {
                if (this_port->phy_table[index] != NULL) {
                        scic_sds_port_write_phy_assignment(
                                this_port, this_port->phy_table[index]
                                );
                }
        }

        scic_sds_port_update_viit_entry(this_port);

        scic_sds_port_resume_port_task_scheduler(this_port);

        /* Post the dummy task for the port so the hardware can schedule
         * io correctly
         */
        scic_sds_port_post_dummy_request(this_port);
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * exiting the SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL. This function reports
 * the port not ready and suspends the port task scheduler. none
 */
static void scic_sds_port_ready_substate_operational_exit(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)object;

        isci_event_port_not_ready(
                scic_sds_port_get_controller(this_port),
                this_port,
                this_port->not_ready_reason
                );
}

/*
 * ******************************************************************************
 * *  PORT READY CONFIGURING METHODS
 * ****************************************************************************** */

/**
 * scic_sds_port_ready_substate_configuring_enter() -
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * exiting the SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL. This function reports
 * the port not ready and suspends the port task scheduler. none
 */
static void scic_sds_port_ready_substate_configuring_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_ready_state_handlers(
                this_port, SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING
                );

        if (this_port->active_phy_mask == 0) {
                isci_event_port_not_ready(
                        scic_sds_port_get_controller(this_port),
                        this_port,
                        SCIC_PORT_NOT_READY_NO_ACTIVE_PHYS
                        );

                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_WAITING
                        );
        } else if (this_port->started_request_count == 0) {
                sci_base_state_machine_change_state(
                        &this_port->ready_substate_machine,
                        SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL
                        );
        }
}

static void scic_sds_port_ready_substate_configuring_exit(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)object;

        scic_sds_port_suspend_port_task_scheduler(this_port);
}

/* --------------------------------------------------------------------------- */

const struct sci_base_state scic_sds_port_ready_substate_table[] = {
        [SCIC_SDS_PORT_READY_SUBSTATE_WAITING] = {
                .enter_state = scic_sds_port_ready_substate_waiting_enter,
        },
        [SCIC_SDS_PORT_READY_SUBSTATE_OPERATIONAL] = {
                .enter_state = scic_sds_port_ready_substate_operational_enter,
                .exit_state  = scic_sds_port_ready_substate_operational_exit
        },
        [SCIC_SDS_PORT_READY_SUBSTATE_CONFIGURING] = {
                .enter_state = scic_sds_port_ready_substate_configuring_enter,
                .exit_state  = scic_sds_port_ready_substate_configuring_exit
        },
};

/*
 * ***************************************************************************
 * *  DEFAULT HANDLERS
 * *************************************************************************** */

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for port a start request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
enum sci_status scic_sds_port_default_start_handler(
        struct sci_base_port *port)
{
        struct scic_sds_port *sci_port = (struct scic_sds_port *)port;

        dev_warn(sciport_to_dev(sci_port),
                 "%s: SCIC Port 0x%p requested to start while in invalid "
                 "state %d\n",
                 __func__,
                 port,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port stop request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
static enum sci_status scic_sds_port_default_stop_handler(
        struct sci_base_port *port)
{
        struct scic_sds_port *sci_port = (struct scic_sds_port *)port;

        dev_warn(sciport_to_dev(sci_port),
                 "%s: SCIC Port 0x%p requested to stop while in invalid "
                 "state %d\n",
                 __func__,
                 port,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port destruct request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
enum sci_status scic_sds_port_default_destruct_handler(
        struct sci_base_port *port)
{
        struct scic_sds_port *sci_port = (struct scic_sds_port *)port;

        dev_warn(sciport_to_dev(sci_port),
                 "%s: SCIC Port 0x%p requested to destruct while in invalid "
                 "state %d\n",
                 __func__,
                 port,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @timeout: This is the timeout for the reset request to complete.
 *
 * This is the default method for a port reset request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
enum sci_status scic_sds_port_default_reset_handler(
        struct sci_base_port *port,
        u32 timeout)
{
        struct scic_sds_port *sci_port = (struct scic_sds_port *)port;

        dev_warn(sciport_to_dev(sci_port),
                 "%s: SCIC Port 0x%p requested to reset while in invalid "
                 "state %d\n",
                 __func__,
                 port,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port add phy request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
static enum sci_status scic_sds_port_default_add_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *sci_port = (struct scic_sds_port *)port;

        dev_warn(sciport_to_dev(sci_port),
                 "%s: SCIC Port 0x%p requested to add phy 0x%p while in "
                 "invalid state %d\n",
                 __func__,
                 port,
                 phy,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port remove phy request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
enum sci_status scic_sds_port_default_remove_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *sci_port = (struct scic_sds_port *)port;

        dev_warn(sciport_to_dev(sci_port),
                 "%s: SCIC Port 0x%p requested to remove phy 0x%p while in "
                 "invalid state %d\n",
                 __func__,
                 port,
                 phy,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port unsolicited frame request.  It will
 * report a warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE Is it even
 * possible to receive an unsolicited frame directed to a port object?  It
 * seems possible if we implementing virtual functions but until then?
 */
enum sci_status scic_sds_port_default_frame_handler(
        struct scic_sds_port *port,
        u32 frame_index)
{
        dev_warn(sciport_to_dev(port),
                 "%s: SCIC Port 0x%p requested to process frame %d while in "
                 "invalid state %d\n",
                 __func__,
                 port,
                 frame_index,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(port)));

        scic_sds_controller_release_frame(
                scic_sds_port_get_controller(port), frame_index
                );

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port event request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
enum sci_status scic_sds_port_default_event_handler(
        struct scic_sds_port *port,
        u32 event_code)
{
        dev_warn(sciport_to_dev(port),
                 "%s: SCIC Port 0x%p requested to process event 0x%x while "
                 "in invalid state %d\n",
                 __func__,
                 port,
                 event_code,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(
                                 (struct scic_sds_port *)port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port link up notification.  It will report
 * a warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
void scic_sds_port_default_link_up_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *phy)
{
        dev_warn(sciport_to_dev(this_port),
                 "%s: SCIC Port 0x%p received link_up notification from phy "
                 "0x%p while in invalid state %d\n",
                 __func__,
                 this_port,
                 phy,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(this_port)));
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port link down notification.  It will
 * report a warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
void scic_sds_port_default_link_down_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *phy)
{
        dev_warn(sciport_to_dev(this_port),
                 "%s: SCIC Port 0x%p received link down notification from "
                 "phy 0x%p while in invalid state %d\n",
                 __func__,
                 this_port,
                 phy,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(this_port)));
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port start io request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
enum sci_status scic_sds_port_default_start_io_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        dev_warn(sciport_to_dev(this_port),
                 "%s: SCIC Port 0x%p requested to start io request 0x%p "
                 "while in invalid state %d\n",
                 __func__,
                 this_port,
                 io_request,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(this_port)));

        return SCI_FAILURE_INVALID_STATE;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This is the default method for a port complete io request.  It will report a
 * warning and exit. enum sci_status SCI_FAILURE_INVALID_STATE
 */
static enum sci_status scic_sds_port_default_complete_io_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        dev_warn(sciport_to_dev(this_port),
                 "%s: SCIC Port 0x%p requested to complete io request 0x%p "
                 "while in invalid state %d\n",
                 __func__,
                 this_port,
                 io_request,
                 sci_base_state_machine_get_state(
                         scic_sds_port_get_base_state_machine(this_port)));

        return SCI_FAILURE_INVALID_STATE;
}

/*
 * ****************************************************************************
 * * GENERAL STATE HANDLERS
 * **************************************************************************** */

/**
 *
 * @port: This is the struct scic_sds_port object on which the io request count will
 *    be decremented.
 * @device: This is the struct scic_sds_remote_device object to which the io request
 *    is being directed.  This parameter is not required to complete this
 *    operation.
 * @io_request: This is the request that is being completed on this port
 *    object.  This parameter is not required to complete this operation.
 *
 * This is a general complete io request handler for the struct scic_sds_port object.
 * enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_general_complete_io_handler(
        struct scic_sds_port *port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        scic_sds_port_decrement_request_count(this_port);

        return SCI_SUCCESS;
}

/*
 * ****************************************************************************
 * * STOPPED STATE HANDLERS
 * **************************************************************************** */

/**
 * scic_sds_port_stopped_state_start_handler() - stop a port from "started"
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This method takes the struct scic_sds_port from a stopped state and attempts to
 * start it.  To start a port it must have no assiged devices and it must have
 * at least one phy assigned to it.  If those conditions are met then the port
 * can transition to the ready state. enum sci_status
 * SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION This struct scic_sds_port object could
 * not be started because the port configuration is not valid. SCI_SUCCESS the
 * start request is successful and the struct scic_sds_port object has transitioned to
 * the SCI_BASE_PORT_STATE_READY.
 */
static enum sci_status scic_sds_port_stopped_state_start_handler(struct sci_base_port *base_port)
{
        struct scic_sds_port *sci_port = container_of(base_port, typeof(*sci_port), parent);
        struct scic_sds_controller *scic = sci_port->owning_controller;
        enum sci_status status = SCI_SUCCESS;
        u32 phy_mask;

        if (sci_port->assigned_device_count > 0) {
                /*
                 * / @todo This is a start failure operation because there are still
                 * /       devices assigned to this port.  There must be no devices
                 * /       assigned to a port on a start operation. */
                return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
        }

        sci_port->timer_handle = isci_event_timer_create(scic,
                                                         scic_sds_port_timeout_handler,
                                                         sci_port);

        if (!sci_port->timer_handle)
                return SCI_FAILURE_INSUFFICIENT_RESOURCES;

        if (sci_port->reserved_rni == SCU_DUMMY_INDEX) {
                u16 rni = scic_sds_remote_node_table_allocate_remote_node(&scic->available_remote_nodes, 1);

                if (rni != SCU_DUMMY_INDEX)
                        scic_sds_port_construct_dummy_rnc(sci_port, rni);
                else
                        status = SCI_FAILURE_INSUFFICIENT_RESOURCES;
                sci_port->reserved_rni = rni;
        }

        if (sci_port->reserved_tci == SCU_DUMMY_INDEX) {
                /* Allocate a TCI and remove the sequence nibble */
                u16 tci = scic_controller_allocate_io_tag(scic);

                if (tci != SCU_DUMMY_INDEX)
                        scic_sds_port_construct_dummy_task(sci_port, tci);
                else
                        status = SCI_FAILURE_INSUFFICIENT_RESOURCES;
                sci_port->reserved_tci = tci;
        }

        if (status == SCI_SUCCESS) {
                phy_mask = scic_sds_port_get_phys(sci_port);

                /*
                 * There are one or more phys assigned to this port.  Make sure
                 * the port's phy mask is in fact legal and supported by the
                 * silicon.
                 */
                if (scic_sds_port_is_phy_mask_valid(sci_port, phy_mask) == true) {
                        sci_base_state_machine_change_state(
                                scic_sds_port_get_base_state_machine(sci_port),
                                SCI_BASE_PORT_STATE_READY);

                        return SCI_SUCCESS;
                } else
                        status = SCI_FAILURE;
        }

        if (status != SCI_SUCCESS)
                scic_sds_port_destroy_dummy_resources(sci_port);

        return status;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This method takes the struct scic_sds_port that is in a stopped state and handles a
 * stop request.  This function takes no action. enum sci_status SCI_SUCCESS the
 * stop request is successful as the struct scic_sds_port object is already stopped.
 */
static enum sci_status scic_sds_port_stopped_state_stop_handler(
        struct sci_base_port *port)
{
        /* We are already stopped so there is nothing to do here */
        return SCI_SUCCESS;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This method takes the struct scic_sds_port that is in a stopped state and handles
 * the destruct request.  The stopped state is the only state in which the
 * struct scic_sds_port can be destroyed.  This function causes the port object to
 * transition to the SCI_BASE_PORT_STATE_FINAL. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_stopped_state_destruct_handler(
        struct sci_base_port *port)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        sci_base_state_machine_stop(&this_port->parent.state_machine);

        return SCI_SUCCESS;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @phy: This is the struct sci_base_phy object which is cast into a struct scic_sds_phy
 *    object.
 *
 * This method takes the struct scic_sds_port that is in a stopped state and handles
 * the add phy request.  In MPC mode the only time a phy can be added to a port
 * is in the SCI_BASE_PORT_STATE_STOPPED. enum sci_status
 * SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION is returned when the phy can not
 * be added to the port. SCI_SUCCESS if the phy is added to the port.
 */
static enum sci_status scic_sds_port_stopped_state_add_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *this_phy  = (struct scic_sds_phy *)phy;
        struct sci_sas_address port_sas_address;

        /* Read the port assigned SAS Address if there is one */
        scic_sds_port_get_sas_address(this_port, &port_sas_address);

        if (port_sas_address.high != 0 && port_sas_address.low != 0) {
                struct sci_sas_address phy_sas_address;

                /*
                 * Make sure that the PHY SAS Address matches the SAS Address
                 * for this port. */
                scic_sds_phy_get_sas_address(this_phy, &phy_sas_address);

                if (
                        (port_sas_address.high != phy_sas_address.high)
                        || (port_sas_address.low  != phy_sas_address.low)
                        ) {
                        return SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION;
                }
        }

        return scic_sds_port_set_phy(this_port, this_phy);
}


/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 * @phy: This is the struct sci_base_phy object which is cast into a struct scic_sds_phy
 *    object.
 *
 * This method takes the struct scic_sds_port that is in a stopped state and handles
 * the remove phy request.  In MPC mode the only time a phy can be removed from
 * a port is in the SCI_BASE_PORT_STATE_STOPPED. enum sci_status
 * SCI_FAILURE_UNSUPPORTED_PORT_CONFIGURATION is returned when the phy can not
 * be added to the port. SCI_SUCCESS if the phy is added to the port.
 */
static enum sci_status scic_sds_port_stopped_state_remove_phy_handler(
        struct sci_base_port *port,
        struct sci_base_phy *phy)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;
        struct scic_sds_phy *this_phy  = (struct scic_sds_phy *)phy;

        return scic_sds_port_clear_phy(this_port, this_phy);
}

/*
 * ****************************************************************************
 * *  READY STATE HANDLERS
 * **************************************************************************** */

/*
 * ****************************************************************************
 * *  RESETTING STATE HANDLERS
 * **************************************************************************** */

/*
 * ****************************************************************************
 * *  STOPPING STATE HANDLERS
 * **************************************************************************** */

/**
 *
 * @port: This is the struct scic_sds_port object on which the io request count will
 *    be decremented.
 * @device: This is the struct scic_sds_remote_device object to which the io request
 *    is being directed.  This parameter is not required to complete this
 *    operation.
 * @io_request: This is the request that is being completed on this port
 *    object.  This parameter is not required to complete this operation.
 *
 * This method takes the struct scic_sds_port that is in a stopping state and handles
 * the complete io request. Should the request count reach 0 then the port
 * object will transition to the stopped state. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_stopping_state_complete_io_handler(
        struct scic_sds_port *port,
        struct scic_sds_remote_device *device,
        struct scic_sds_request *io_request)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        scic_sds_port_decrement_request_count(this_port);

        if (this_port->started_request_count == 0) {
                sci_base_state_machine_change_state(
                        scic_sds_port_get_base_state_machine(this_port),
                        SCI_BASE_PORT_STATE_STOPPED
                        );
        }

        return SCI_SUCCESS;
}

/*
 * ****************************************************************************
 * *  RESETTING STATE HANDLERS
 * **************************************************************************** */

/**
 *
 * @port: This is the port object which is being requested to stop.
 *
 * This method will stop a failed port.  This causes a transition to the
 * stopping state. enum sci_status SCI_SUCCESS
 */
static enum sci_status scic_sds_port_reset_state_stop_handler(
        struct sci_base_port *port)
{
        struct scic_sds_port *this_port = (struct scic_sds_port *)port;

        sci_base_state_machine_change_state(
                &this_port->parent.state_machine,
                SCI_BASE_PORT_STATE_STOPPING
                );

        return SCI_SUCCESS;
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This method will transition a failed port to its ready state.  The port
 * failed because a hard reset request timed out but at some time later one or
 * more phys in the port became ready. enum sci_status SCI_SUCCESS
 */
static void scic_sds_port_reset_state_link_up_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *phy)
{
        /*
         * / @todo We should make sure that the phy that has gone link up is the same
         * /       one on which we sent the reset.  It is possible that the phy on
         * /       which we sent the reset is not the one that has gone link up and we
         * /       want to make sure that phy being reset comes back.  Consider the
         * /       case where a reset is sent but before the hardware processes the
         * /       reset it get a link up on the port because of a hot plug event.
         * /       because of the reset request this phy will go link down almost
         * /       immediately. */

        /*
         * In the resetting state we don't notify the user regarding
         * link up and link down notifications. */
        scic_sds_port_general_link_up_handler(this_port, phy, false);
}

/**
 *
 * @port: This is the struct sci_base_port object which is cast into a struct scic_sds_port
 *    object.
 *
 * This method process link down notifications that occur during a port reset
 * operation. Link downs can occur during the reset operation. enum sci_status
 * SCI_SUCCESS
 */
static void scic_sds_port_reset_state_link_down_handler(
        struct scic_sds_port *this_port,
        struct scic_sds_phy *phy)
{
        /*
         * In the resetting state we don't notify the user regarding
         * link up and link down notifications. */
        scic_sds_port_deactivate_phy(this_port, phy, false);
}

/* --------------------------------------------------------------------------- */

struct scic_sds_port_state_handler
scic_sds_port_state_handler_table[SCI_BASE_PORT_MAX_STATES] =
{
        /* SCI_BASE_PORT_STATE_STOPPED */
        {
                {
                        scic_sds_port_stopped_state_start_handler,
                        scic_sds_port_stopped_state_stop_handler,
                        scic_sds_port_stopped_state_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_stopped_state_add_phy_handler,
                        scic_sds_port_stopped_state_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_default_link_up_handler,
                scic_sds_port_default_link_down_handler,
                scic_sds_port_default_start_io_handler,
                scic_sds_port_default_complete_io_handler
        },
        /* SCI_BASE_PORT_STATE_STOPPING */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_default_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_default_add_phy_handler,
                        scic_sds_port_default_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_default_link_up_handler,
                scic_sds_port_default_link_down_handler,
                scic_sds_port_default_start_io_handler,
                scic_sds_port_stopping_state_complete_io_handler
        },
        /* SCI_BASE_PORT_STATE_READY */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_default_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_default_add_phy_handler,
                        scic_sds_port_default_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_default_link_up_handler,
                scic_sds_port_default_link_down_handler,
                scic_sds_port_default_start_io_handler,
                scic_sds_port_general_complete_io_handler
        },
        /* SCI_BASE_PORT_STATE_RESETTING */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_reset_state_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_default_add_phy_handler,
                        scic_sds_port_default_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_reset_state_link_up_handler,
                scic_sds_port_reset_state_link_down_handler,
                scic_sds_port_default_start_io_handler,
                scic_sds_port_general_complete_io_handler
        },
        /* SCI_BASE_PORT_STATE_FAILED */
        {
                {
                        scic_sds_port_default_start_handler,
                        scic_sds_port_default_stop_handler,
                        scic_sds_port_default_destruct_handler,
                        scic_sds_port_default_reset_handler,
                        scic_sds_port_default_add_phy_handler,
                        scic_sds_port_default_remove_phy_handler
                },
                scic_sds_port_default_frame_handler,
                scic_sds_port_default_event_handler,
                scic_sds_port_default_link_up_handler,
                scic_sds_port_default_link_down_handler,
                scic_sds_port_default_start_io_handler,
                scic_sds_port_general_complete_io_handler
        }
};

/*
 * ******************************************************************************
 * *  PORT STATE PRIVATE METHODS
 * ****************************************************************************** */

/**
 *
 * @this_port: This is the port object which to suspend.
 *
 * This method will enable the SCU Port Task Scheduler for this port object but
 * will leave the port task scheduler in a suspended state. none
 */
static void scic_sds_port_enable_port_task_scheduler(
        struct scic_sds_port *this_port)
{
        u32 pts_control_value;

        pts_control_value = scu_port_task_scheduler_read(this_port, control);

        pts_control_value |= SCU_PTSxCR_GEN_BIT(ENABLE) | SCU_PTSxCR_GEN_BIT(SUSPEND);

        scu_port_task_scheduler_write(this_port, control, pts_control_value);
}

/**
 *
 * @this_port: This is the port object which to resume.
 *
 * This method will disable the SCU port task scheduler for this port object.
 * none
 */
static void scic_sds_port_disable_port_task_scheduler(
        struct scic_sds_port *this_port)
{
        u32 pts_control_value;

        pts_control_value = scu_port_task_scheduler_read(this_port, control);

        pts_control_value &= ~(SCU_PTSxCR_GEN_BIT(ENABLE)
                               | SCU_PTSxCR_GEN_BIT(SUSPEND));

        scu_port_task_scheduler_write(this_port, control, pts_control_value);
}

void scic_sds_port_post_dummy_remote_node(struct scic_sds_port *sci_port)
{
        struct scic_sds_controller *scic = sci_port->owning_controller;
        u8 phys_index = sci_port->physical_port_index;
        union scu_remote_node_context *rnc;
        u16 rni = sci_port->reserved_rni;
        u32 command;

        rnc = &scic->remote_node_context_table[rni];
        rnc->ssp.is_valid = true;

        command = SCU_CONTEXT_COMMAND_POST_RNC_32 |
                  phys_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT | rni;

        scic_sds_controller_post_request(scic, command);

        /* ensure hardware has seen the post rnc command and give it
         * ample time to act before sending the suspend
         */
        SMU_ISR_READ(scic); /* flush */
        udelay(10);

        command = SCU_CONTEXT_COMMAND_POST_RNC_SUSPEND_TX_RX |
                  phys_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT | rni;

        scic_sds_controller_post_request(scic, command);
}

void scic_sds_port_invalidate_dummy_remote_node(struct scic_sds_port *sci_port)
{
        struct scic_sds_controller *scic = sci_port->owning_controller;
        u8 phys_index = sci_port->physical_port_index;
        union scu_remote_node_context *rnc;
        u16 rni = sci_port->reserved_rni;
        u32 command;

        rnc = &scic->remote_node_context_table[rni];

        rnc->ssp.is_valid = false;

        command = SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE |
                  phys_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT | rni;

        scic_sds_controller_post_request(scic, command);
}

/*
 * ******************************************************************************
 * *  PORT STATE METHODS
 * ****************************************************************************** */

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCI_BASE_PORT_STATE_STOPPED. This function sets the stopped
 * state handlers for the struct scic_sds_port object and disables the port task
 * scheduler in the hardware. none
 */
static void scic_sds_port_stopped_state_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_base_state_handlers(
                this_port, SCI_BASE_PORT_STATE_STOPPED
                );

        if (
                SCI_BASE_PORT_STATE_STOPPING
                == this_port->parent.state_machine.previous_state_id
                ) {
                /*
                 * If we enter this state becasuse of a request to stop
                 * the port then we want to disable the hardwares port
                 * task scheduler. */
                scic_sds_port_disable_port_task_scheduler(this_port);
        }
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * exiting the SCI_BASE_STATE_STOPPED. This function enables the SCU hardware
 * port task scheduler. none
 */
static void scic_sds_port_stopped_state_exit(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        /* Enable and suspend the port task scheduler */
        scic_sds_port_enable_port_task_scheduler(this_port);
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCI_BASE_PORT_STATE_READY. This function sets the ready state
 * handlers for the struct scic_sds_port object, reports the port object as not ready
 * and starts the ready substate machine. none
 */
static void scic_sds_port_ready_state_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        /* Put the ready state handlers in place though they will not be there long */
        scic_sds_port_set_base_state_handlers(
                this_port, SCI_BASE_PORT_STATE_READY
                );

        if (
                SCI_BASE_PORT_STATE_RESETTING
                == this_port->parent.state_machine.previous_state_id
                ) {
                isci_event_port_hard_reset_complete(
                        scic_sds_port_get_controller(this_port),
                        this_port,
                        SCI_SUCCESS
                        );
        } else {
                /* Notify the caller that the port is not yet ready */
                isci_event_port_not_ready(
                        scic_sds_port_get_controller(this_port),
                        this_port,
                        SCIC_PORT_NOT_READY_NO_ACTIVE_PHYS
                        );
        }

        /* Post and suspend the dummy remote node context for this port. */
        scic_sds_port_post_dummy_remote_node(this_port);

        /* Start the ready substate machine */
        sci_base_state_machine_start(
                scic_sds_port_get_ready_substate_machine(this_port)
                );
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * exiting the SCI_BASE_STATE_READY. This function does nothing. none
 */
static void scic_sds_port_ready_state_exit(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        sci_base_state_machine_stop(&this_port->ready_substate_machine);

        scic_sds_port_invalidate_dummy_remote_node(this_port);
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCI_BASE_PORT_STATE_RESETTING. This function sets the resetting
 * state handlers for the struct scic_sds_port object. none
 */
static void scic_sds_port_resetting_state_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_base_state_handlers(
                this_port, SCI_BASE_PORT_STATE_RESETTING
                );
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * exiting the SCI_BASE_STATE_RESETTING. This function does nothing. none
 */
static void scic_sds_port_resetting_state_exit(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        isci_event_timer_stop(
                scic_sds_port_get_controller(this_port),
                this_port->timer_handle
                );
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCI_BASE_PORT_STATE_STOPPING. This function sets the stopping
 * state handlers for the struct scic_sds_port object. none
 */
static void scic_sds_port_stopping_state_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_base_state_handlers(
                this_port, SCI_BASE_PORT_STATE_STOPPING
                );
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * exiting the SCI_BASE_STATE_STOPPING. This function does nothing. none
 */
static void scic_sds_port_stopping_state_exit(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        isci_event_timer_stop(
                scic_sds_port_get_controller(this_port),
                this_port->timer_handle
                );

        scic_sds_port_destroy_dummy_resources(this_port);
}

/**
 *
 * @object: This is the struct sci_base_object which is cast to a struct scic_sds_port object.
 *
 * This method will perform the actions required by the struct scic_sds_port on
 * entering the SCI_BASE_PORT_STATE_STOPPING. This function sets the stopping
 * state handlers for the struct scic_sds_port object. none
 */
static void scic_sds_port_failed_state_enter(
        struct sci_base_object *object)
{
        struct scic_sds_port *this_port;

        this_port = (struct scic_sds_port *)object;

        scic_sds_port_set_base_state_handlers(
                this_port,
                SCI_BASE_PORT_STATE_FAILED
                );

        isci_event_port_hard_reset_complete(
                scic_sds_port_get_controller(this_port),
                this_port,
                SCI_FAILURE_TIMEOUT
                );
}

/* --------------------------------------------------------------------------- */

const struct sci_base_state scic_sds_port_state_table[] = {
        [SCI_BASE_PORT_STATE_STOPPED] = {
                .enter_state = scic_sds_port_stopped_state_enter,
                .exit_state  = scic_sds_port_stopped_state_exit
        },
        [SCI_BASE_PORT_STATE_STOPPING] = {
                .enter_state = scic_sds_port_stopping_state_enter,
                .exit_state  = scic_sds_port_stopping_state_exit
        },
        [SCI_BASE_PORT_STATE_READY] = {
                .enter_state = scic_sds_port_ready_state_enter,
                .exit_state  = scic_sds_port_ready_state_exit
        },
        [SCI_BASE_PORT_STATE_RESETTING] = {
                .enter_state = scic_sds_port_resetting_state_enter,
                .exit_state  = scic_sds_port_resetting_state_exit
        },
        [SCI_BASE_PORT_STATE_FAILED] = {
                .enter_state = scic_sds_port_failed_state_enter,
        }
};