/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * BSD LICENSE
 *
 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
#include <dev/isci/isci.h>

#include <sys/conf.h>
#include <sys/malloc.h>

#include <cam/cam_periph.h>
#include <cam/cam_xpt_periph.h>

#include <dev/isci/scil/sci_memory_descriptor_list.h>
#include <dev/isci/scil/sci_memory_descriptor_list_decorator.h>

#include <dev/isci/scil/scif_controller.h>
#include <dev/isci/scil/scif_library.h>
#include <dev/isci/scil/scif_io_request.h>
#include <dev/isci/scil/scif_task_request.h>
#include <dev/isci/scil/scif_remote_device.h>
#include <dev/isci/scil/scif_domain.h>
#include <dev/isci/scil/scif_user_callback.h>
#include <dev/isci/scil/scic_sgpio.h>

#include <dev/led/led.h>

void isci_action(struct cam_sim *sim, union ccb *ccb);
void isci_poll(struct cam_sim *sim);

#define ccb_sim_ptr sim_priv.entries[0].ptr

/**
 * @brief This user callback will inform the user that the controller has
 *        had a serious unexpected error.  The user should not the error,
 *        disable interrupts, and wait for current ongoing processing to
 *        complete.  Subsequently, the user should reset the controller.
 *
 * @param[in]  controller This parameter specifies the controller that had
 *                        an error.
 *
 * @return none
 */
void scif_cb_controller_error(SCI_CONTROLLER_HANDLE_T controller,
    SCI_CONTROLLER_ERROR error)
{

        isci_log_message(0, "ISCI", "scif_cb_controller_error: 0x%x\n",
            error);
}

/**
 * @brief This user callback will inform the user that the controller has
 *        finished the start process.
 *
 * @param[in]  controller This parameter specifies the controller that was
 *             started.
 * @param[in]  completion_status This parameter specifies the results of
 *             the start operation.  SCI_SUCCESS indicates successful
 *             completion.
 *
 * @return none
 */
void scif_cb_controller_start_complete(SCI_CONTROLLER_HANDLE_T controller,
    SCI_STATUS completion_status)
{
        uint32_t index;
        struct ISCI_CONTROLLER *isci_controller = (struct ISCI_CONTROLLER *)
            sci_object_get_association(controller);

        isci_controller->is_started = TRUE;

        /* Set bits for all domains.  We will clear them one-by-one once
         *  the domains complete discovery, or return error when calling
         *  scif_domain_discover.  Once all bits are clear, we will register
         *  the controller with CAM.
         */
        isci_controller->initial_discovery_mask = (1 << SCI_MAX_DOMAINS) - 1;

        for(index = 0; index < SCI_MAX_DOMAINS; index++) {
                SCI_STATUS status;
                SCI_DOMAIN_HANDLE_T domain =
                    isci_controller->domain[index].sci_object;

                status = scif_domain_discover(
                        domain,
                        scif_domain_get_suggested_discover_timeout(domain),
                        DEVICE_TIMEOUT
                );

                if (status != SCI_SUCCESS)
                {
                        isci_controller_domain_discovery_complete(
                            isci_controller, &isci_controller->domain[index]);
                }
        }
}

/**
 * @brief This user callback will inform the user that the controller has
 *        finished the stop process. Note, after user calls
 *        scif_controller_stop(), before user receives this controller stop
 *        complete callback, user should not expect any callback from
 *        framework, such like scif_cb_domain_change_notification().
 *
 * @param[in]  controller This parameter specifies the controller that was
 *             stopped.
 * @param[in]  completion_status This parameter specifies the results of
 *             the stop operation.  SCI_SUCCESS indicates successful
 *             completion.
 *
 * @return none
 */
void scif_cb_controller_stop_complete(SCI_CONTROLLER_HANDLE_T controller,
    SCI_STATUS completion_status)
{
        struct ISCI_CONTROLLER *isci_controller = (struct ISCI_CONTROLLER *)
            sci_object_get_association(controller);

        isci_controller->is_started = FALSE;
}

static void
isci_single_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
{
        SCI_PHYSICAL_ADDRESS *phys_addr = arg;

        *phys_addr = seg[0].ds_addr;
}

/**
 * @brief This method will be invoked to allocate memory dynamically.
 *
 * @param[in]  controller This parameter represents the controller
 *             object for which to allocate memory.
 * @param[out] mde This parameter represents the memory descriptor to
 *             be filled in by the user that will reference the newly
 *             allocated memory.
 *
 * @return none
 */
void scif_cb_controller_allocate_memory(SCI_CONTROLLER_HANDLE_T controller,
    SCI_PHYSICAL_MEMORY_DESCRIPTOR_T *mde)
{
        struct ISCI_CONTROLLER *isci_controller = (struct ISCI_CONTROLLER *)
            sci_object_get_association(controller);

        /*
         * Note this routine is only used for buffers needed to translate
         * SCSI UNMAP commands to ATA DSM commands for SATA disks.
         *
         * We first try to pull a buffer from the controller's pool, and only
         * call contigmalloc if one isn't there.
         */
        if (!sci_pool_empty(isci_controller->unmap_buffer_pool)) {
                sci_pool_get(isci_controller->unmap_buffer_pool,
                    mde->virtual_address);
        } else
                mde->virtual_address = contigmalloc(PAGE_SIZE,
                    M_ISCI, M_NOWAIT, 0, BUS_SPACE_MAXADDR,
                    mde->constant_memory_alignment, 0);

        if (mde->virtual_address != NULL)
                bus_dmamap_load(isci_controller->buffer_dma_tag,
                    NULL, mde->virtual_address, PAGE_SIZE,
                    isci_single_map, &mde->physical_address,
                    BUS_DMA_NOWAIT);
}

/**
 * @brief This method will be invoked to allocate memory dynamically.
 *
 * @param[in]  controller This parameter represents the controller
 *             object for which to allocate memory.
 * @param[out] mde This parameter represents the memory descriptor to
 *             be filled in by the user that will reference the newly
 *             allocated memory.
 *
 * @return none
 */
void scif_cb_controller_free_memory(SCI_CONTROLLER_HANDLE_T controller,
    SCI_PHYSICAL_MEMORY_DESCRIPTOR_T * mde)
{
        struct ISCI_CONTROLLER *isci_controller = (struct ISCI_CONTROLLER *)
            sci_object_get_association(controller);

        /*
         * Put the buffer back into the controller's buffer pool, rather
         * than invoking configfree.  This helps reduce chance we won't
         * have buffers available when system is under memory pressure.
         */ 
        sci_pool_put(isci_controller->unmap_buffer_pool,
            mde->virtual_address);
}

void isci_controller_construct(struct ISCI_CONTROLLER *controller,
    struct isci_softc *isci)
{
        SCI_CONTROLLER_HANDLE_T scif_controller_handle;

        scif_library_allocate_controller(isci->sci_library_handle,
            &scif_controller_handle);

        scif_controller_construct(isci->sci_library_handle,
            scif_controller_handle, NULL);

        controller->isci = isci;
        controller->scif_controller_handle = scif_controller_handle;

        /* This allows us to later use
         *  sci_object_get_association(scif_controller_handle)
         * inside of a callback routine to get our struct ISCI_CONTROLLER object
         */
        sci_object_set_association(scif_controller_handle, (void *)controller);

        controller->is_started = FALSE;
        controller->is_frozen = FALSE;
        controller->release_queued_ccbs = FALSE;
        controller->sim = NULL;
        controller->initial_discovery_mask = 0;

        sci_fast_list_init(&controller->pending_device_reset_list);

        mtx_init(&controller->lock, "isci", NULL, MTX_DEF);

        uint32_t domain_index;

        for(domain_index = 0; domain_index < SCI_MAX_DOMAINS; domain_index++) {
                isci_domain_construct( &controller->domain[domain_index],
                    domain_index, controller);
        }

        controller->timer_memory = malloc(
            sizeof(struct ISCI_TIMER) * SCI_MAX_TIMERS, M_ISCI,
            M_NOWAIT | M_ZERO);

        sci_pool_initialize(controller->timer_pool);

        struct ISCI_TIMER *timer = (struct ISCI_TIMER *)
            controller->timer_memory;

        for ( int i = 0; i < SCI_MAX_TIMERS; i++ ) {
                sci_pool_put(controller->timer_pool, timer++);
        }

        sci_pool_initialize(controller->unmap_buffer_pool);
}

static void isci_led_fault_func(void *priv, int onoff)
{
        struct ISCI_PHY *phy = priv;

        /* map onoff to the fault LED */
        phy->led_fault = onoff;
        scic_sgpio_update_led_state(phy->handle, 1 << phy->index, 
                phy->led_fault, phy->led_locate, 0);
}

static void isci_led_locate_func(void *priv, int onoff)
{
        struct ISCI_PHY *phy = priv;

        /* map onoff to the locate LED */
        phy->led_locate = onoff;
        scic_sgpio_update_led_state(phy->handle, 1 << phy->index, 
                phy->led_fault, phy->led_locate, 0);
}

SCI_STATUS isci_controller_initialize(struct ISCI_CONTROLLER *controller)
{
        SCIC_USER_PARAMETERS_T scic_user_parameters;
        SCI_CONTROLLER_HANDLE_T scic_controller_handle;
        char led_name[64];
        unsigned long tunable;
        uint32_t io_shortage;
        uint32_t fail_on_timeout;
        int i;

        scic_controller_handle =
            scif_controller_get_scic_handle(controller->scif_controller_handle);

        if (controller->isci->oem_parameters_found == TRUE)
        {
                scic_oem_parameters_set(
                    scic_controller_handle,
                    &controller->oem_parameters,
                    (uint8_t)(controller->oem_parameters_version));
        }

        scic_user_parameters_get(scic_controller_handle, &scic_user_parameters);

        if (TUNABLE_ULONG_FETCH("hw.isci.no_outbound_task_timeout", &tunable))
                scic_user_parameters.sds1.no_outbound_task_timeout =
                    (uint8_t)tunable;

        if (TUNABLE_ULONG_FETCH("hw.isci.ssp_max_occupancy_timeout", &tunable))
                scic_user_parameters.sds1.ssp_max_occupancy_timeout =
                    (uint16_t)tunable;

        if (TUNABLE_ULONG_FETCH("hw.isci.stp_max_occupancy_timeout", &tunable))
                scic_user_parameters.sds1.stp_max_occupancy_timeout =
                    (uint16_t)tunable;

        if (TUNABLE_ULONG_FETCH("hw.isci.ssp_inactivity_timeout", &tunable))
                scic_user_parameters.sds1.ssp_inactivity_timeout =
                    (uint16_t)tunable;

        if (TUNABLE_ULONG_FETCH("hw.isci.stp_inactivity_timeout", &tunable))
                scic_user_parameters.sds1.stp_inactivity_timeout =
                    (uint16_t)tunable;

        if (TUNABLE_ULONG_FETCH("hw.isci.max_speed_generation", &tunable))
                for (i = 0; i < SCI_MAX_PHYS; i++)
                        scic_user_parameters.sds1.phys[i].max_speed_generation =
                            (uint8_t)tunable;

        scic_user_parameters_set(scic_controller_handle, &scic_user_parameters);

        /* Scheduler bug in SCU requires SCIL to reserve some task contexts as a
         *  a workaround - one per domain.
         */
        controller->queue_depth = SCI_MAX_IO_REQUESTS - SCI_MAX_DOMAINS;

        if (TUNABLE_INT_FETCH("hw.isci.controller_queue_depth",
            &controller->queue_depth)) {
                controller->queue_depth = max(1, min(controller->queue_depth,
                    SCI_MAX_IO_REQUESTS - SCI_MAX_DOMAINS));
        }

        /* Reserve one request so that we can ensure we have one available TC
         *  to do internal device resets.
         */
        controller->sim_queue_depth = controller->queue_depth - 1;

        /* Although we save one TC to do internal device resets, it is possible
         *  we could end up using several TCs for simultaneous device resets
         *  while at the same time having CAM fill our controller queue.  To
         *  simulate this condition, and how our driver handles it, we can set
         *  this io_shortage parameter, which will tell CAM that we have a
         *  large queue depth than we really do.
         */
        io_shortage = 0;
        TUNABLE_INT_FETCH("hw.isci.io_shortage", &io_shortage);
        controller->sim_queue_depth += io_shortage;

        fail_on_timeout = 1;
        TUNABLE_INT_FETCH("hw.isci.fail_on_task_timeout", &fail_on_timeout);
        controller->fail_on_task_timeout = fail_on_timeout;

        /* Attach to CAM using xpt_bus_register now, then immediately freeze
         *  the simq.  It will get released later when initial domain discovery
         *  is complete.
         */
        controller->has_been_scanned = FALSE;
        mtx_lock(&controller->lock);
        isci_controller_attach_to_cam(controller);
        xpt_freeze_simq(controller->sim, 1);
        mtx_unlock(&controller->lock);

        for (i = 0; i < SCI_MAX_PHYS; i++) {
                controller->phys[i].handle = scic_controller_handle;
                controller->phys[i].index = i;

                /* fault */
                controller->phys[i].led_fault = 0;
                sprintf(led_name, "isci.bus%d.port%d.fault", controller->index, i);
                controller->phys[i].cdev_fault = led_create(isci_led_fault_func,
                    &controller->phys[i], led_name);
                        
                /* locate */
                controller->phys[i].led_locate = 0;
                sprintf(led_name, "isci.bus%d.port%d.locate", controller->index, i);
                controller->phys[i].cdev_locate = led_create(isci_led_locate_func,
                    &controller->phys[i], led_name);
        }

        return (scif_controller_initialize(controller->scif_controller_handle));
}

int isci_controller_allocate_memory(struct ISCI_CONTROLLER *controller)
{
        int error;
        device_t device =  controller->isci->device;
        uint32_t max_segment_size = isci_io_request_get_max_io_size();
        struct ISCI_MEMORY *uncached_controller_memory =
            &controller->uncached_controller_memory;
        struct ISCI_MEMORY *cached_controller_memory =
            &controller->cached_controller_memory;
        struct ISCI_MEMORY *request_memory =
            &controller->request_memory;
        POINTER_UINT virtual_address;
        bus_addr_t physical_address;

        controller->mdl = sci_controller_get_memory_descriptor_list_handle(
            controller->scif_controller_handle);

        uncached_controller_memory->size = sci_mdl_decorator_get_memory_size(
            controller->mdl, SCI_MDE_ATTRIBUTE_PHYSICALLY_CONTIGUOUS);

        error = isci_allocate_dma_buffer(device, controller,
            uncached_controller_memory);

        if (error != 0)
            return (error);

        sci_mdl_decorator_assign_memory( controller->mdl,
            SCI_MDE_ATTRIBUTE_PHYSICALLY_CONTIGUOUS,
            uncached_controller_memory->virtual_address,
            uncached_controller_memory->physical_address);

        cached_controller_memory->size = sci_mdl_decorator_get_memory_size(
            controller->mdl,
            SCI_MDE_ATTRIBUTE_CACHEABLE | SCI_MDE_ATTRIBUTE_PHYSICALLY_CONTIGUOUS
        );

        error = isci_allocate_dma_buffer(device, controller,
            cached_controller_memory);

        if (error != 0)
            return (error);

        sci_mdl_decorator_assign_memory(controller->mdl,
            SCI_MDE_ATTRIBUTE_CACHEABLE | SCI_MDE_ATTRIBUTE_PHYSICALLY_CONTIGUOUS,
            cached_controller_memory->virtual_address,
            cached_controller_memory->physical_address);

        request_memory->size =
            controller->queue_depth * isci_io_request_get_object_size();

        error = isci_allocate_dma_buffer(device, controller, request_memory);

        if (error != 0)
            return (error);

        /* For STP PIO testing, we want to ensure we can force multiple SGLs
         *  since this has been a problem area in SCIL.  This tunable parameter
         *  will allow us to force DMA segments to a smaller size, ensuring
         *  that even if a physically contiguous buffer is attached to this
         *  I/O, the DMA subsystem will pass us multiple segments in our DMA
         *  load callback.
         */
        TUNABLE_INT_FETCH("hw.isci.max_segment_size", &max_segment_size);

        /* Create DMA tag for our I/O requests.  Then we can create DMA maps based off
         *  of this tag and store them in each of our ISCI_IO_REQUEST objects.  This
         *  will enable better performance than creating the DMA maps every time we get
         *  an I/O.
         */
        error = bus_dma_tag_create(bus_get_dma_tag(device), 0x1,
            ISCI_DMA_BOUNDARY, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
            NULL, NULL, isci_io_request_get_max_io_size(),
            SCI_MAX_SCATTER_GATHER_ELEMENTS, max_segment_size, 0,
            busdma_lock_mutex, &controller->lock,
            &controller->buffer_dma_tag);

        if (error != 0)
            return (error);

        sci_pool_initialize(controller->request_pool);

        virtual_address = request_memory->virtual_address;
        physical_address = request_memory->physical_address;

        for (int i = 0; i < controller->queue_depth; i++) {
                struct ISCI_REQUEST *request =
                    (struct ISCI_REQUEST *)virtual_address;

                isci_request_construct(request,
                    controller->scif_controller_handle,
                    controller->buffer_dma_tag, physical_address);

                sci_pool_put(controller->request_pool, request);

                virtual_address += isci_request_get_object_size();
                physical_address += isci_request_get_object_size();
        }

        uint32_t remote_device_size = sizeof(struct ISCI_REMOTE_DEVICE) +
            scif_remote_device_get_object_size();

        controller->remote_device_memory = (uint8_t *) malloc(
            remote_device_size * SCI_MAX_REMOTE_DEVICES, M_ISCI,
            M_NOWAIT | M_ZERO);

        sci_pool_initialize(controller->remote_device_pool);

        uint8_t *remote_device_memory_ptr = controller->remote_device_memory;

        for (int i = 0; i < SCI_MAX_REMOTE_DEVICES; i++) {
                struct ISCI_REMOTE_DEVICE *remote_device =
                    (struct ISCI_REMOTE_DEVICE *)remote_device_memory_ptr;

                controller->remote_device[i] = NULL;
                remote_device->index = i;
                remote_device->is_resetting = FALSE;
                remote_device->frozen_lun_mask = 0;
                sci_fast_list_element_init(remote_device,
                    &remote_device->pending_device_reset_element);
                TAILQ_INIT(&remote_device->queued_ccbs);
                remote_device->release_queued_ccb = FALSE;
                remote_device->queued_ccb_in_progress = NULL;

                /*
                 * For the first SCI_MAX_DOMAINS device objects, do not put
                 *  them in the pool, rather assign them to each domain.  This
                 *  ensures that any device attached directly to port "i" will
                 *  always get CAM target id "i".
                 */
                if (i < SCI_MAX_DOMAINS)
                        controller->domain[i].da_remote_device = remote_device;
                else
                        sci_pool_put(controller->remote_device_pool,
                            remote_device);
                remote_device_memory_ptr += remote_device_size;
        }

        return (0);
}

void isci_controller_start(void *controller_handle)
{
        struct ISCI_CONTROLLER *controller =
            (struct ISCI_CONTROLLER *)controller_handle;
        SCI_CONTROLLER_HANDLE_T scif_controller_handle =
            controller->scif_controller_handle;

        scif_controller_start(scif_controller_handle,
            scif_controller_get_suggested_start_timeout(scif_controller_handle));

        scic_controller_enable_interrupts(
            scif_controller_get_scic_handle(controller->scif_controller_handle));
}

void isci_controller_domain_discovery_complete(
    struct ISCI_CONTROLLER *isci_controller, struct ISCI_DOMAIN *isci_domain)
{
        if (!isci_controller->has_been_scanned)
        {
                /* Controller has not been scanned yet.  We'll clear
                 *  the discovery bit for this domain, then check if all bits
                 *  are now clear.  That would indicate that all domains are
                 *  done with discovery and we can then proceed with initial
                 *  scan.
                 */

                isci_controller->initial_discovery_mask &=
                    ~(1 << isci_domain->index);

                if (isci_controller->initial_discovery_mask == 0) {
                        struct isci_softc *driver = isci_controller->isci;
                        uint8_t next_index = isci_controller->index + 1;

                        isci_controller->has_been_scanned = TRUE;

                        /* Unfreeze simq to allow initial scan to proceed. */
                        xpt_release_simq(isci_controller->sim, TRUE);

                        if (next_index < driver->controller_count) {
                                /*  There are more controllers that need to
                                 *   start.  So start the next one.
                                 */
                                isci_controller_start(
                                    &driver->controllers[next_index]);
                        }
                        else
                        {
                                /* All controllers have been started and completed discovery.
                                 *  Disestablish the config hook while will signal to the
                                 *  kernel during boot that it is safe to try to find and
                                 *  mount the root partition.
                                 */
                                config_intrhook_disestablish(
                                    &driver->config_hook);
                        }
                }
        }
}

int isci_controller_attach_to_cam(struct ISCI_CONTROLLER *controller)
{
        struct isci_softc *isci = controller->isci;
        device_t parent = device_get_parent(isci->device);
        int unit = device_get_unit(isci->device);
        struct cam_devq *isci_devq = cam_simq_alloc(controller->sim_queue_depth);

        if(isci_devq == NULL) {
                isci_log_message(0, "ISCI", "isci_devq is NULL \n");
                return (-1);
        }

        controller->sim = cam_sim_alloc(isci_action, isci_poll, "isci",
            controller, unit, &controller->lock, controller->sim_queue_depth,
            controller->sim_queue_depth, isci_devq);

        if(controller->sim == NULL) {
                isci_log_message(0, "ISCI", "cam_sim_alloc... fails\n");
                cam_simq_free(isci_devq);
                return (-1);
        }

        if(xpt_bus_register(controller->sim, parent, controller->index)
            != CAM_SUCCESS) {
                isci_log_message(0, "ISCI", "xpt_bus_register...fails \n");
                cam_sim_free(controller->sim, TRUE);
                mtx_unlock(&controller->lock);
                return (-1);
        }

        if(xpt_create_path(&controller->path, NULL,
            cam_sim_path(controller->sim), CAM_TARGET_WILDCARD,
            CAM_LUN_WILDCARD) != CAM_REQ_CMP) {
                isci_log_message(0, "ISCI", "xpt_create_path....fails\n");
                xpt_bus_deregister(cam_sim_path(controller->sim));
                cam_sim_free(controller->sim, TRUE);
                mtx_unlock(&controller->lock);
                return (-1);
        }

        return (0);
}

void isci_poll(struct cam_sim *sim)
{
        struct ISCI_CONTROLLER *controller =
            (struct ISCI_CONTROLLER *)cam_sim_softc(sim);

        isci_interrupt_poll_handler(controller);
}

void isci_action(struct cam_sim *sim, union ccb *ccb)
{
        struct ISCI_CONTROLLER *controller =
            (struct ISCI_CONTROLLER *)cam_sim_softc(sim);

        switch ( ccb->ccb_h.func_code ) {
        case XPT_PATH_INQ:
                {
                        struct ccb_pathinq *cpi = &ccb->cpi;
                        int bus = cam_sim_bus(sim);
                        ccb->ccb_h.ccb_sim_ptr = sim;
                        cpi->version_num = 1;
                        cpi->hba_inquiry = PI_TAG_ABLE;
                        cpi->target_sprt = 0;
                        cpi->hba_misc = PIM_NOBUSRESET | PIM_SEQSCAN |
                            PIM_UNMAPPED;
                        cpi->hba_eng_cnt = 0;
                        cpi->max_target = SCI_MAX_REMOTE_DEVICES - 1;
                        cpi->max_lun = ISCI_MAX_LUN;
                        cpi->maxio = isci_io_request_get_max_io_size();
                        cpi->unit_number = cam_sim_unit(sim);
                        cpi->bus_id = bus;
                        cpi->initiator_id = SCI_MAX_REMOTE_DEVICES;
                        cpi->base_transfer_speed = 300000;
                        strlcpy(cpi->sim_vid, "FreeBSD", SIM_IDLEN);
                        strlcpy(cpi->hba_vid, "Intel Corp.", HBA_IDLEN);
                        strlcpy(cpi->dev_name, cam_sim_name(sim), DEV_IDLEN);
                        cpi->transport = XPORT_SAS;
                        cpi->transport_version = 0;
                        cpi->protocol = PROTO_SCSI;
                        cpi->protocol_version = SCSI_REV_SPC2;
                        cpi->ccb_h.status = CAM_REQ_CMP;
                        xpt_done(ccb);
                }
                break;
        case XPT_GET_TRAN_SETTINGS:
                {
                        struct ccb_trans_settings *general_settings = &ccb->cts;
                        struct ccb_trans_settings_sas *sas_settings =
                            &general_settings->xport_specific.sas;
                        struct ccb_trans_settings_scsi *scsi_settings =
                            &general_settings->proto_specific.scsi;
                        struct ISCI_REMOTE_DEVICE *remote_device;

                        remote_device = controller->remote_device[ccb->ccb_h.target_id];

                        if (remote_device == NULL) {
                                ccb->ccb_h.status &= ~CAM_SIM_QUEUED;
                                ccb->ccb_h.status &= ~CAM_STATUS_MASK;
                                ccb->ccb_h.status |= CAM_DEV_NOT_THERE;
                                xpt_done(ccb);
                                break;
                        }

                        general_settings->protocol = PROTO_SCSI;
                        general_settings->transport = XPORT_SAS;
                        general_settings->protocol_version = SCSI_REV_SPC2;
                        general_settings->transport_version = 0;
                        scsi_settings->valid = CTS_SCSI_VALID_TQ;
                        scsi_settings->flags = CTS_SCSI_FLAGS_TAG_ENB;
                        ccb->ccb_h.status &= ~CAM_STATUS_MASK;
                        ccb->ccb_h.status |= CAM_REQ_CMP;

                        sas_settings->bitrate =
                            isci_remote_device_get_bitrate(remote_device);

                        if (sas_settings->bitrate != 0)
                                sas_settings->valid = CTS_SAS_VALID_SPEED;

                        xpt_done(ccb);
                }
                break;
        case XPT_SCSI_IO:
                if (ccb->ccb_h.flags & CAM_CDB_PHYS) {
                        ccb->ccb_h.status = CAM_REQ_INVALID;
                        xpt_done(ccb);
                        break;
                }
                isci_io_request_execute_scsi_io(ccb, controller);
                break;
        case XPT_SMP_IO:
                isci_io_request_execute_smp_io(ccb, controller);
                break;
        case XPT_SET_TRAN_SETTINGS:
                ccb->ccb_h.status &= ~CAM_STATUS_MASK;
                ccb->ccb_h.status |= CAM_REQ_CMP;
                xpt_done(ccb);
                break;
        case XPT_CALC_GEOMETRY:
                cam_calc_geometry(&ccb->ccg, /*extended*/1);
                xpt_done(ccb);
                break;
        case XPT_RESET_DEV:
                {
                        struct ISCI_REMOTE_DEVICE *remote_device =
                            controller->remote_device[ccb->ccb_h.target_id];

                        if (remote_device != NULL)
                                isci_remote_device_reset(remote_device, ccb);
                        else {
                                ccb->ccb_h.status &= ~CAM_SIM_QUEUED;
                                ccb->ccb_h.status &= ~CAM_STATUS_MASK;
                                ccb->ccb_h.status |= CAM_DEV_NOT_THERE;
                                xpt_done(ccb);
                        }
                }
                break;
        case XPT_RESET_BUS:
                ccb->ccb_h.status = CAM_REQ_CMP;
                xpt_done(ccb);
                break;
        default:
                isci_log_message(0, "ISCI", "Unhandled func_code 0x%x\n",
                    ccb->ccb_h.func_code);
                ccb->ccb_h.status &= ~CAM_SIM_QUEUED;
                ccb->ccb_h.status &= ~CAM_STATUS_MASK;
                ccb->ccb_h.status |= CAM_REQ_INVALID;
                xpt_done(ccb);
                break;
        }
}

/*
 * Unfortunately, SCIL doesn't cleanly handle retry conditions.
 *  CAM_REQUEUE_REQ works only when no one is using the pass(4) interface.  So
 *  when SCIL denotes an I/O needs to be retried (typically because of mixing
 *  tagged/non-tagged ATA commands, or running out of NCQ slots), we queue
 *  these I/O internally.  Once SCIL completes an I/O to this device, or we get
 *  a ready notification, we will retry the first I/O on the queue.
 *  Unfortunately, SCIL also doesn't cleanly handle starting the new I/O within
 *  the context of the completion handler, so we need to retry these I/O after
 *  the completion handler is done executing.
 */
void
isci_controller_release_queued_ccbs(struct ISCI_CONTROLLER *controller)
{
        struct ISCI_REMOTE_DEVICE *dev;
        struct ccb_hdr *ccb_h;
        uint8_t *ptr;
        int dev_idx;

        KASSERT(mtx_owned(&controller->lock), ("controller lock not owned"));

        controller->release_queued_ccbs = FALSE;
        for (dev_idx = 0;
             dev_idx < SCI_MAX_REMOTE_DEVICES;
             dev_idx++) {

                dev = controller->remote_device[dev_idx];
                if (dev != NULL &&
                    dev->release_queued_ccb == TRUE &&
                    dev->queued_ccb_in_progress == NULL) {
                        dev->release_queued_ccb = FALSE;
                        ccb_h = TAILQ_FIRST(&dev->queued_ccbs);

                        if (ccb_h == NULL)
                                continue;

                        ptr = scsiio_cdb_ptr(&((union ccb *)ccb_h)->csio);
                        isci_log_message(1, "ISCI", "release %p %x\n", ccb_h, *ptr);

                        dev->queued_ccb_in_progress = (union ccb *)ccb_h;
                        isci_io_request_execute_scsi_io(
                            (union ccb *)ccb_h, controller);
                }
        }
}