Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / scsi / isci / remote_device.c
diff --git a/kernel/drivers/scsi/isci/remote_device.c b/kernel/drivers/scsi/isci/remote_device.c
new file mode 100644 (file)
index 0000000..cc51f38
--- /dev/null
@@ -0,0 +1,1726 @@
+/*
+ * This file is provided under a dual BSD/GPLv2 license.  When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in
+ *     the documentation and/or other materials provided with the
+ *     distribution.
+ *   * Neither the name of Intel Corporation nor the names of its
+ *     contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include <scsi/sas.h>
+#include <linux/bitops.h>
+#include "isci.h"
+#include "port.h"
+#include "remote_device.h"
+#include "request.h"
+#include "remote_node_context.h"
+#include "scu_event_codes.h"
+#include "task.h"
+
+#undef C
+#define C(a) (#a)
+const char *dev_state_name(enum sci_remote_device_states state)
+{
+       static const char * const strings[] = REMOTE_DEV_STATES;
+
+       return strings[state];
+}
+#undef C
+
+enum sci_status sci_remote_device_suspend(struct isci_remote_device *idev,
+                                         enum sci_remote_node_suspension_reasons reason)
+{
+       return sci_remote_node_context_suspend(&idev->rnc, reason,
+                                              SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT);
+}
+
+/**
+ * isci_remote_device_ready() - This function is called by the ihost when the
+ *    remote device is ready. We mark the isci device as ready and signal the
+ *    waiting proccess.
+ * @ihost: our valid isci_host
+ * @idev: remote device
+ *
+ */
+static void isci_remote_device_ready(struct isci_host *ihost, struct isci_remote_device *idev)
+{
+       dev_dbg(&ihost->pdev->dev,
+               "%s: idev = %p\n", __func__, idev);
+
+       clear_bit(IDEV_IO_NCQERROR, &idev->flags);
+       set_bit(IDEV_IO_READY, &idev->flags);
+       if (test_and_clear_bit(IDEV_START_PENDING, &idev->flags))
+               wake_up(&ihost->eventq);
+}
+
+static enum sci_status sci_remote_device_terminate_req(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev,
+       int check_abort,
+       struct isci_request *ireq)
+{
+       if (!test_bit(IREQ_ACTIVE, &ireq->flags) ||
+           (ireq->target_device != idev) ||
+           (check_abort && !test_bit(IREQ_PENDING_ABORT, &ireq->flags)))
+               return SCI_SUCCESS;
+
+       dev_dbg(&ihost->pdev->dev,
+               "%s: idev=%p; flags=%lx; req=%p; req target=%p\n",
+               __func__, idev, idev->flags, ireq, ireq->target_device);
+
+       set_bit(IREQ_ABORT_PATH_ACTIVE, &ireq->flags);
+
+       return sci_controller_terminate_request(ihost, idev, ireq);
+}
+
+static enum sci_status sci_remote_device_terminate_reqs_checkabort(
+       struct isci_remote_device *idev,
+       int chk)
+{
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+       enum sci_status status  = SCI_SUCCESS;
+       u32 i;
+
+       for (i = 0; i < SCI_MAX_IO_REQUESTS; i++) {
+               struct isci_request *ireq = ihost->reqs[i];
+               enum sci_status s;
+
+               s = sci_remote_device_terminate_req(ihost, idev, chk, ireq);
+               if (s != SCI_SUCCESS)
+                       status = s;
+       }
+       return status;
+}
+
+static bool isci_compare_suspendcount(
+       struct isci_remote_device *idev,
+       u32 localcount)
+{
+       smp_rmb();
+
+       /* Check for a change in the suspend count, or the RNC
+        * being destroyed.
+        */
+       return (localcount != idev->rnc.suspend_count)
+           || sci_remote_node_context_is_being_destroyed(&idev->rnc);
+}
+
+static bool isci_check_reqterm(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev,
+       struct isci_request *ireq,
+       u32 localcount)
+{
+       unsigned long flags;
+       bool res;
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       res = isci_compare_suspendcount(idev, localcount)
+               && !test_bit(IREQ_ABORT_PATH_ACTIVE, &ireq->flags);
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+       return res;
+}
+
+static bool isci_check_devempty(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev,
+       u32 localcount)
+{
+       unsigned long flags;
+       bool res;
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       res = isci_compare_suspendcount(idev, localcount)
+               && idev->started_request_count == 0;
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+       return res;
+}
+
+enum sci_status isci_remote_device_terminate_requests(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev,
+       struct isci_request *ireq)
+{
+       enum sci_status status = SCI_SUCCESS;
+       unsigned long flags;
+       u32 rnc_suspend_count;
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+
+       if (isci_get_device(idev) == NULL) {
+               dev_dbg(&ihost->pdev->dev, "%s: failed isci_get_device(idev=%p)\n",
+                       __func__, idev);
+               spin_unlock_irqrestore(&ihost->scic_lock, flags);
+               status = SCI_FAILURE;
+       } else {
+               /* If already suspended, don't wait for another suspension. */
+               smp_rmb();
+               rnc_suspend_count
+                       = sci_remote_node_context_is_suspended(&idev->rnc)
+                               ? 0 : idev->rnc.suspend_count;
+
+               dev_dbg(&ihost->pdev->dev,
+                       "%s: idev=%p, ireq=%p; started_request_count=%d, "
+                               "rnc_suspend_count=%d, rnc.suspend_count=%d"
+                               "about to wait\n",
+                       __func__, idev, ireq, idev->started_request_count,
+                       rnc_suspend_count, idev->rnc.suspend_count);
+
+               #define MAX_SUSPEND_MSECS 10000
+               if (ireq) {
+                       /* Terminate a specific TC. */
+                       set_bit(IREQ_NO_AUTO_FREE_TAG, &ireq->flags);
+                       sci_remote_device_terminate_req(ihost, idev, 0, ireq);
+                       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+                       if (!wait_event_timeout(ihost->eventq,
+                                               isci_check_reqterm(ihost, idev, ireq,
+                                                                  rnc_suspend_count),
+                                               msecs_to_jiffies(MAX_SUSPEND_MSECS))) {
+
+                               dev_warn(&ihost->pdev->dev, "%s host%d timeout single\n",
+                                        __func__, ihost->id);
+                               dev_dbg(&ihost->pdev->dev,
+                                        "%s: ******* Timeout waiting for "
+                                        "suspend; idev=%p, current state %s; "
+                                        "started_request_count=%d, flags=%lx\n\t"
+                                        "rnc_suspend_count=%d, rnc.suspend_count=%d "
+                                        "RNC: current state %s, current "
+                                        "suspend_type %x dest state %d;\n"
+                                        "ireq=%p, ireq->flags = %lx\n",
+                                        __func__, idev,
+                                        dev_state_name(idev->sm.current_state_id),
+                                        idev->started_request_count, idev->flags,
+                                        rnc_suspend_count, idev->rnc.suspend_count,
+                                        rnc_state_name(idev->rnc.sm.current_state_id),
+                                        idev->rnc.suspend_type,
+                                        idev->rnc.destination_state,
+                                        ireq, ireq->flags);
+                       }
+                       spin_lock_irqsave(&ihost->scic_lock, flags);
+                       clear_bit(IREQ_NO_AUTO_FREE_TAG, &ireq->flags);
+                       if (!test_bit(IREQ_ABORT_PATH_ACTIVE, &ireq->flags))
+                               isci_free_tag(ihost, ireq->io_tag);
+                       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+               } else {
+                       /* Terminate all TCs. */
+                       sci_remote_device_terminate_requests(idev);
+                       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+                       if (!wait_event_timeout(ihost->eventq,
+                                               isci_check_devempty(ihost, idev,
+                                                                   rnc_suspend_count),
+                                               msecs_to_jiffies(MAX_SUSPEND_MSECS))) {
+
+                               dev_warn(&ihost->pdev->dev, "%s host%d timeout all\n",
+                                        __func__, ihost->id);
+                               dev_dbg(&ihost->pdev->dev,
+                                       "%s: ******* Timeout waiting for "
+                                       "suspend; idev=%p, current state %s; "
+                                       "started_request_count=%d, flags=%lx\n\t"
+                                       "rnc_suspend_count=%d, "
+                                       "RNC: current state %s, "
+                                       "rnc.suspend_count=%d, current "
+                                       "suspend_type %x dest state %d\n",
+                                       __func__, idev,
+                                       dev_state_name(idev->sm.current_state_id),
+                                       idev->started_request_count, idev->flags,
+                                       rnc_suspend_count,
+                                       rnc_state_name(idev->rnc.sm.current_state_id),
+                                       idev->rnc.suspend_count,
+                                       idev->rnc.suspend_type,
+                                       idev->rnc.destination_state);
+                       }
+               }
+               dev_dbg(&ihost->pdev->dev, "%s: idev=%p, wait done\n",
+                       __func__, idev);
+               isci_put_device(idev);
+       }
+       return status;
+}
+
+/**
+* isci_remote_device_not_ready() - This function is called by the ihost when
+*    the remote device is not ready. We mark the isci device as ready (not
+*    "ready_for_io") and signal the waiting proccess.
+* @isci_host: This parameter specifies the isci host object.
+* @isci_device: This parameter specifies the remote device
+*
+* sci_lock is held on entrance to this function.
+*/
+static void isci_remote_device_not_ready(struct isci_host *ihost,
+                                        struct isci_remote_device *idev,
+                                        u32 reason)
+{
+       dev_dbg(&ihost->pdev->dev,
+               "%s: isci_device = %p; reason = %d\n", __func__, idev, reason);
+
+       switch (reason) {
+       case SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED:
+               set_bit(IDEV_IO_NCQERROR, &idev->flags);
+
+               /* Suspend the remote device so the I/O can be terminated. */
+               sci_remote_device_suspend(idev, SCI_SW_SUSPEND_NORMAL);
+
+               /* Kill all outstanding requests for the device. */
+               sci_remote_device_terminate_requests(idev);
+
+               /* Fall through into the default case... */
+       default:
+               clear_bit(IDEV_IO_READY, &idev->flags);
+               break;
+       }
+}
+
+/* called once the remote node context is ready to be freed.
+ * The remote device can now report that its stop operation is complete. none
+ */
+static void rnc_destruct_done(void *_dev)
+{
+       struct isci_remote_device *idev = _dev;
+
+       BUG_ON(idev->started_request_count != 0);
+       sci_change_state(&idev->sm, SCI_DEV_STOPPED);
+}
+
+enum sci_status sci_remote_device_terminate_requests(
+       struct isci_remote_device *idev)
+{
+       return sci_remote_device_terminate_reqs_checkabort(idev, 0);
+}
+
+enum sci_status sci_remote_device_stop(struct isci_remote_device *idev,
+                                       u32 timeout)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+
+       switch (state) {
+       case SCI_DEV_INITIAL:
+       case SCI_DEV_FAILED:
+       case SCI_DEV_FINAL:
+       default:
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       case SCI_DEV_STOPPED:
+               return SCI_SUCCESS;
+       case SCI_DEV_STARTING:
+               /* device not started so there had better be no requests */
+               BUG_ON(idev->started_request_count != 0);
+               sci_remote_node_context_destruct(&idev->rnc,
+                                                     rnc_destruct_done, idev);
+               /* Transition to the stopping state and wait for the
+                * remote node to complete being posted and invalidated.
+                */
+               sci_change_state(sm, SCI_DEV_STOPPING);
+               return SCI_SUCCESS;
+       case SCI_DEV_READY:
+       case SCI_STP_DEV_IDLE:
+       case SCI_STP_DEV_CMD:
+       case SCI_STP_DEV_NCQ:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_STP_DEV_AWAIT_RESET:
+       case SCI_SMP_DEV_IDLE:
+       case SCI_SMP_DEV_CMD:
+               sci_change_state(sm, SCI_DEV_STOPPING);
+               if (idev->started_request_count == 0)
+                       sci_remote_node_context_destruct(&idev->rnc,
+                                                        rnc_destruct_done,
+                                                        idev);
+               else {
+                       sci_remote_device_suspend(
+                               idev, SCI_SW_SUSPEND_LINKHANG_DETECT);
+                       sci_remote_device_terminate_requests(idev);
+               }
+               return SCI_SUCCESS;
+       case SCI_DEV_STOPPING:
+               /* All requests should have been terminated, but if there is an
+                * attempt to stop a device already in the stopping state, then
+                * try again to terminate.
+                */
+               return sci_remote_device_terminate_requests(idev);
+       case SCI_DEV_RESETTING:
+               sci_change_state(sm, SCI_DEV_STOPPING);
+               return SCI_SUCCESS;
+       }
+}
+
+enum sci_status sci_remote_device_reset(struct isci_remote_device *idev)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+
+       switch (state) {
+       case SCI_DEV_INITIAL:
+       case SCI_DEV_STOPPED:
+       case SCI_DEV_STARTING:
+       case SCI_SMP_DEV_IDLE:
+       case SCI_SMP_DEV_CMD:
+       case SCI_DEV_STOPPING:
+       case SCI_DEV_FAILED:
+       case SCI_DEV_RESETTING:
+       case SCI_DEV_FINAL:
+       default:
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       case SCI_DEV_READY:
+       case SCI_STP_DEV_IDLE:
+       case SCI_STP_DEV_CMD:
+       case SCI_STP_DEV_NCQ:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_STP_DEV_AWAIT_RESET:
+               sci_change_state(sm, SCI_DEV_RESETTING);
+               return SCI_SUCCESS;
+       }
+}
+
+enum sci_status sci_remote_device_reset_complete(struct isci_remote_device *idev)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+
+       if (state != SCI_DEV_RESETTING) {
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       }
+
+       sci_change_state(sm, SCI_DEV_READY);
+       return SCI_SUCCESS;
+}
+
+enum sci_status sci_remote_device_frame_handler(struct isci_remote_device *idev,
+                                                    u32 frame_index)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+       enum sci_status status;
+
+       switch (state) {
+       case SCI_DEV_INITIAL:
+       case SCI_DEV_STOPPED:
+       case SCI_DEV_STARTING:
+       case SCI_STP_DEV_IDLE:
+       case SCI_SMP_DEV_IDLE:
+       case SCI_DEV_FINAL:
+       default:
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               /* Return the frame back to the controller */
+               sci_controller_release_frame(ihost, frame_index);
+               return SCI_FAILURE_INVALID_STATE;
+       case SCI_DEV_READY:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_STP_DEV_AWAIT_RESET:
+       case SCI_DEV_STOPPING:
+       case SCI_DEV_FAILED:
+       case SCI_DEV_RESETTING: {
+               struct isci_request *ireq;
+               struct ssp_frame_hdr hdr;
+               void *frame_header;
+               ssize_t word_cnt;
+
+               status = sci_unsolicited_frame_control_get_header(&ihost->uf_control,
+                                                                      frame_index,
+                                                                      &frame_header);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               word_cnt = sizeof(hdr) / sizeof(u32);
+               sci_swab32_cpy(&hdr, frame_header, word_cnt);
+
+               ireq = sci_request_by_tag(ihost, be16_to_cpu(hdr.tag));
+               if (ireq && ireq->target_device == idev) {
+                       /* The IO request is now in charge of releasing the frame */
+                       status = sci_io_request_frame_handler(ireq, frame_index);
+               } else {
+                       /* We could not map this tag to a valid IO
+                        * request Just toss the frame and continue
+                        */
+                       sci_controller_release_frame(ihost, frame_index);
+               }
+               break;
+       }
+       case SCI_STP_DEV_NCQ: {
+               struct dev_to_host_fis *hdr;
+
+               status = sci_unsolicited_frame_control_get_header(&ihost->uf_control,
+                                                                      frame_index,
+                                                                      (void **)&hdr);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               if (hdr->fis_type == FIS_SETDEVBITS &&
+                   (hdr->status & ATA_ERR)) {
+                       idev->not_ready_reason = SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED;
+
+                       /* TODO Check sactive and complete associated IO if any. */
+                       sci_change_state(sm, SCI_STP_DEV_NCQ_ERROR);
+               } else if (hdr->fis_type == FIS_REGD2H &&
+                          (hdr->status & ATA_ERR)) {
+                       /*
+                        * Some devices return D2H FIS when an NCQ error is detected.
+                        * Treat this like an SDB error FIS ready reason.
+                        */
+                       idev->not_ready_reason = SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED;
+                       sci_change_state(&idev->sm, SCI_STP_DEV_NCQ_ERROR);
+               } else
+                       status = SCI_FAILURE;
+
+               sci_controller_release_frame(ihost, frame_index);
+               break;
+       }
+       case SCI_STP_DEV_CMD:
+       case SCI_SMP_DEV_CMD:
+               /* The device does not process any UF received from the hardware while
+                * in this state.  All unsolicited frames are forwarded to the io request
+                * object.
+                */
+               status = sci_io_request_frame_handler(idev->working_request, frame_index);
+               break;
+       }
+
+       return status;
+}
+
+static bool is_remote_device_ready(struct isci_remote_device *idev)
+{
+
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+
+       switch (state) {
+       case SCI_DEV_READY:
+       case SCI_STP_DEV_IDLE:
+       case SCI_STP_DEV_CMD:
+       case SCI_STP_DEV_NCQ:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_STP_DEV_AWAIT_RESET:
+       case SCI_SMP_DEV_IDLE:
+       case SCI_SMP_DEV_CMD:
+               return true;
+       default:
+               return false;
+       }
+}
+
+/*
+ * called once the remote node context has transisitioned to a ready
+ * state (after suspending RX and/or TX due to early D2H fis)
+ */
+static void atapi_remote_device_resume_done(void *_dev)
+{
+       struct isci_remote_device *idev = _dev;
+       struct isci_request *ireq = idev->working_request;
+
+       sci_change_state(&ireq->sm, SCI_REQ_COMPLETED);
+}
+
+enum sci_status sci_remote_device_event_handler(struct isci_remote_device *idev,
+                                                    u32 event_code)
+{
+       enum sci_status status;
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+
+       switch (scu_get_event_type(event_code)) {
+       case SCU_EVENT_TYPE_RNC_OPS_MISC:
+       case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
+       case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
+               status = sci_remote_node_context_event_handler(&idev->rnc, event_code);
+               break;
+       case SCU_EVENT_TYPE_PTX_SCHEDULE_EVENT:
+               if (scu_get_event_code(event_code) == SCU_EVENT_IT_NEXUS_TIMEOUT) {
+                       status = SCI_SUCCESS;
+
+                       /* Suspend the associated RNC */
+                       sci_remote_device_suspend(idev, SCI_SW_SUSPEND_NORMAL);
+
+                       dev_dbg(scirdev_to_dev(idev),
+                               "%s: device: %p event code: %x: %s\n",
+                               __func__, idev, event_code,
+                               is_remote_device_ready(idev)
+                               ? "I_T_Nexus_Timeout event"
+                               : "I_T_Nexus_Timeout event in wrong state");
+
+                       break;
+               }
+       /* Else, fall through and treat as unhandled... */
+       default:
+               dev_dbg(scirdev_to_dev(idev),
+                       "%s: device: %p event code: %x: %s\n",
+                       __func__, idev, event_code,
+                       is_remote_device_ready(idev)
+                       ? "unexpected event"
+                       : "unexpected event in wrong state");
+               status = SCI_FAILURE_INVALID_STATE;
+               break;
+       }
+
+       if (status != SCI_SUCCESS)
+               return status;
+
+       /* Decode device-specific states that may require an RNC resume during
+        * normal operation.  When the abort path is active, these resumes are
+        * managed when the abort path exits.
+        */
+       if (state == SCI_STP_DEV_ATAPI_ERROR) {
+               /* For ATAPI error state resume the RNC right away. */
+               if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
+                   scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX) {
+                       return sci_remote_node_context_resume(&idev->rnc,
+                                                             atapi_remote_device_resume_done,
+                                                             idev);
+               }
+       }
+
+       if (state == SCI_STP_DEV_IDLE) {
+
+               /* We pick up suspension events to handle specifically to this
+                * state. We resume the RNC right away.
+                */
+               if (scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX ||
+                   scu_get_event_type(event_code) == SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX)
+                       status = sci_remote_node_context_resume(&idev->rnc, NULL, NULL);
+       }
+
+       return status;
+}
+
+static void sci_remote_device_start_request(struct isci_remote_device *idev,
+                                                struct isci_request *ireq,
+                                                enum sci_status status)
+{
+       struct isci_port *iport = idev->owning_port;
+
+       /* cleanup requests that failed after starting on the port */
+       if (status != SCI_SUCCESS)
+               sci_port_complete_io(iport, idev, ireq);
+       else {
+               kref_get(&idev->kref);
+               idev->started_request_count++;
+       }
+}
+
+enum sci_status sci_remote_device_start_io(struct isci_host *ihost,
+                                               struct isci_remote_device *idev,
+                                               struct isci_request *ireq)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+       struct isci_port *iport = idev->owning_port;
+       enum sci_status status;
+
+       switch (state) {
+       case SCI_DEV_INITIAL:
+       case SCI_DEV_STOPPED:
+       case SCI_DEV_STARTING:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_DEV_STOPPING:
+       case SCI_DEV_FAILED:
+       case SCI_DEV_RESETTING:
+       case SCI_DEV_FINAL:
+       default:
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       case SCI_DEV_READY:
+               /* attempt to start an io request for this device object. The remote
+                * device object will issue the start request for the io and if
+                * successful it will start the request for the port object then
+                * increment its own request count.
+                */
+               status = sci_port_start_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               status = sci_remote_node_context_start_io(&idev->rnc, ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               status = sci_request_start(ireq);
+               break;
+       case SCI_STP_DEV_IDLE: {
+               /* handle the start io operation for a sata device that is in
+                * the command idle state. - Evalute the type of IO request to
+                * be started - If its an NCQ request change to NCQ substate -
+                * If its any other command change to the CMD substate
+                *
+                * If this is a softreset we may want to have a different
+                * substate.
+                */
+               enum sci_remote_device_states new_state;
+               struct sas_task *task = isci_request_access_task(ireq);
+
+               status = sci_port_start_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               status = sci_remote_node_context_start_io(&idev->rnc, ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               status = sci_request_start(ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               if (task->ata_task.use_ncq)
+                       new_state = SCI_STP_DEV_NCQ;
+               else {
+                       idev->working_request = ireq;
+                       new_state = SCI_STP_DEV_CMD;
+               }
+               sci_change_state(sm, new_state);
+               break;
+       }
+       case SCI_STP_DEV_NCQ: {
+               struct sas_task *task = isci_request_access_task(ireq);
+
+               if (task->ata_task.use_ncq) {
+                       status = sci_port_start_io(iport, idev, ireq);
+                       if (status != SCI_SUCCESS)
+                               return status;
+
+                       status = sci_remote_node_context_start_io(&idev->rnc, ireq);
+                       if (status != SCI_SUCCESS)
+                               break;
+
+                       status = sci_request_start(ireq);
+               } else
+                       return SCI_FAILURE_INVALID_STATE;
+               break;
+       }
+       case SCI_STP_DEV_AWAIT_RESET:
+               return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
+       case SCI_SMP_DEV_IDLE:
+               status = sci_port_start_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               status = sci_remote_node_context_start_io(&idev->rnc, ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               status = sci_request_start(ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               idev->working_request = ireq;
+               sci_change_state(&idev->sm, SCI_SMP_DEV_CMD);
+               break;
+       case SCI_STP_DEV_CMD:
+       case SCI_SMP_DEV_CMD:
+               /* device is already handling a command it can not accept new commands
+                * until this one is complete.
+                */
+               return SCI_FAILURE_INVALID_STATE;
+       }
+
+       sci_remote_device_start_request(idev, ireq, status);
+       return status;
+}
+
+static enum sci_status common_complete_io(struct isci_port *iport,
+                                         struct isci_remote_device *idev,
+                                         struct isci_request *ireq)
+{
+       enum sci_status status;
+
+       status = sci_request_complete(ireq);
+       if (status != SCI_SUCCESS)
+               return status;
+
+       status = sci_port_complete_io(iport, idev, ireq);
+       if (status != SCI_SUCCESS)
+               return status;
+
+       sci_remote_device_decrement_request_count(idev);
+       return status;
+}
+
+enum sci_status sci_remote_device_complete_io(struct isci_host *ihost,
+                                                  struct isci_remote_device *idev,
+                                                  struct isci_request *ireq)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+       struct isci_port *iport = idev->owning_port;
+       enum sci_status status;
+
+       switch (state) {
+       case SCI_DEV_INITIAL:
+       case SCI_DEV_STOPPED:
+       case SCI_DEV_STARTING:
+       case SCI_STP_DEV_IDLE:
+       case SCI_SMP_DEV_IDLE:
+       case SCI_DEV_FAILED:
+       case SCI_DEV_FINAL:
+       default:
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       case SCI_DEV_READY:
+       case SCI_STP_DEV_AWAIT_RESET:
+       case SCI_DEV_RESETTING:
+               status = common_complete_io(iport, idev, ireq);
+               break;
+       case SCI_STP_DEV_CMD:
+       case SCI_STP_DEV_NCQ:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_STP_DEV_ATAPI_ERROR:
+               status = common_complete_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               if (ireq->sci_status == SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED) {
+                       /* This request causes hardware error, device needs to be Lun Reset.
+                        * So here we force the state machine to IDLE state so the rest IOs
+                        * can reach RNC state handler, these IOs will be completed by RNC with
+                        * status of "DEVICE_RESET_REQUIRED", instead of "INVALID STATE".
+                        */
+                       sci_change_state(sm, SCI_STP_DEV_AWAIT_RESET);
+               } else if (idev->started_request_count == 0)
+                       sci_change_state(sm, SCI_STP_DEV_IDLE);
+               break;
+       case SCI_SMP_DEV_CMD:
+               status = common_complete_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+               sci_change_state(sm, SCI_SMP_DEV_IDLE);
+               break;
+       case SCI_DEV_STOPPING:
+               status = common_complete_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               if (idev->started_request_count == 0)
+                       sci_remote_node_context_destruct(&idev->rnc,
+                                                        rnc_destruct_done,
+                                                        idev);
+               break;
+       }
+
+       if (status != SCI_SUCCESS)
+               dev_err(scirdev_to_dev(idev),
+                       "%s: Port:0x%p Device:0x%p Request:0x%p Status:0x%x "
+                       "could not complete\n", __func__, iport,
+                       idev, ireq, status);
+       else
+               isci_put_device(idev);
+
+       return status;
+}
+
+static void sci_remote_device_continue_request(void *dev)
+{
+       struct isci_remote_device *idev = dev;
+
+       /* we need to check if this request is still valid to continue. */
+       if (idev->working_request)
+               sci_controller_continue_io(idev->working_request);
+}
+
+enum sci_status sci_remote_device_start_task(struct isci_host *ihost,
+                                                 struct isci_remote_device *idev,
+                                                 struct isci_request *ireq)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+       struct isci_port *iport = idev->owning_port;
+       enum sci_status status;
+
+       switch (state) {
+       case SCI_DEV_INITIAL:
+       case SCI_DEV_STOPPED:
+       case SCI_DEV_STARTING:
+       case SCI_SMP_DEV_IDLE:
+       case SCI_SMP_DEV_CMD:
+       case SCI_DEV_STOPPING:
+       case SCI_DEV_FAILED:
+       case SCI_DEV_RESETTING:
+       case SCI_DEV_FINAL:
+       default:
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       case SCI_STP_DEV_IDLE:
+       case SCI_STP_DEV_CMD:
+       case SCI_STP_DEV_NCQ:
+       case SCI_STP_DEV_NCQ_ERROR:
+       case SCI_STP_DEV_AWAIT_RESET:
+               status = sci_port_start_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               status = sci_request_start(ireq);
+               if (status != SCI_SUCCESS)
+                       goto out;
+
+               /* Note: If the remote device state is not IDLE this will
+                * replace the request that probably resulted in the task
+                * management request.
+                */
+               idev->working_request = ireq;
+               sci_change_state(sm, SCI_STP_DEV_CMD);
+
+               /* The remote node context must cleanup the TCi to NCQ mapping
+                * table.  The only way to do this correctly is to either write
+                * to the TLCR register or to invalidate and repost the RNC. In
+                * either case the remote node context state machine will take
+                * the correct action when the remote node context is suspended
+                * and later resumed.
+                */
+               sci_remote_device_suspend(idev,
+                                         SCI_SW_SUSPEND_LINKHANG_DETECT);
+
+               status = sci_remote_node_context_start_task(&idev->rnc, ireq,
+                               sci_remote_device_continue_request, idev);
+
+       out:
+               sci_remote_device_start_request(idev, ireq, status);
+               /* We need to let the controller start request handler know that
+                * it can't post TC yet. We will provide a callback function to
+                * post TC when RNC gets resumed.
+                */
+               return SCI_FAILURE_RESET_DEVICE_PARTIAL_SUCCESS;
+       case SCI_DEV_READY:
+               status = sci_port_start_io(iport, idev, ireq);
+               if (status != SCI_SUCCESS)
+                       return status;
+
+               /* Resume the RNC as needed: */
+               status = sci_remote_node_context_start_task(&idev->rnc, ireq,
+                                                           NULL, NULL);
+               if (status != SCI_SUCCESS)
+                       break;
+
+               status = sci_request_start(ireq);
+               break;
+       }
+       sci_remote_device_start_request(idev, ireq, status);
+
+       return status;
+}
+
+void sci_remote_device_post_request(struct isci_remote_device *idev, u32 request)
+{
+       struct isci_port *iport = idev->owning_port;
+       u32 context;
+
+       context = request |
+                 (ISCI_PEG << SCU_CONTEXT_COMMAND_PROTOCOL_ENGINE_GROUP_SHIFT) |
+                 (iport->physical_port_index << SCU_CONTEXT_COMMAND_LOGICAL_PORT_SHIFT) |
+                 idev->rnc.remote_node_index;
+
+       sci_controller_post_request(iport->owning_controller, context);
+}
+
+/* called once the remote node context has transisitioned to a
+ * ready state.  This is the indication that the remote device object can also
+ * transition to ready.
+ */
+static void remote_device_resume_done(void *_dev)
+{
+       struct isci_remote_device *idev = _dev;
+
+       if (is_remote_device_ready(idev))
+               return;
+
+       /* go 'ready' if we are not already in a ready state */
+       sci_change_state(&idev->sm, SCI_DEV_READY);
+}
+
+static void sci_stp_remote_device_ready_idle_substate_resume_complete_handler(void *_dev)
+{
+       struct isci_remote_device *idev = _dev;
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       /* For NCQ operation we do not issue a isci_remote_device_not_ready().
+        * As a result, avoid sending the ready notification.
+        */
+       if (idev->sm.previous_state_id != SCI_STP_DEV_NCQ)
+               isci_remote_device_ready(ihost, idev);
+}
+
+static void sci_remote_device_initial_state_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+
+       /* Initial state is a transitional state to the stopped state */
+       sci_change_state(&idev->sm, SCI_DEV_STOPPED);
+}
+
+/**
+ * sci_remote_device_destruct() - free remote node context and destruct
+ * @remote_device: This parameter specifies the remote device to be destructed.
+ *
+ * Remote device objects are a limited resource.  As such, they must be
+ * protected.  Thus calls to construct and destruct are mutually exclusive and
+ * non-reentrant. The return value shall indicate if the device was
+ * successfully destructed or if some failure occurred. enum sci_status This value
+ * is returned if the device is successfully destructed.
+ * SCI_FAILURE_INVALID_REMOTE_DEVICE This value is returned if the supplied
+ * device isn't valid (e.g. it's already been destoryed, the handle isn't
+ * valid, etc.).
+ */
+static enum sci_status sci_remote_device_destruct(struct isci_remote_device *idev)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+       struct isci_host *ihost;
+
+       if (state != SCI_DEV_STOPPED) {
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       }
+
+       ihost = idev->owning_port->owning_controller;
+       sci_controller_free_remote_node_context(ihost, idev,
+                                                    idev->rnc.remote_node_index);
+       idev->rnc.remote_node_index = SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX;
+       sci_change_state(sm, SCI_DEV_FINAL);
+
+       return SCI_SUCCESS;
+}
+
+/**
+ * isci_remote_device_deconstruct() - This function frees an isci_remote_device.
+ * @ihost: This parameter specifies the isci host object.
+ * @idev: This parameter specifies the remote device to be freed.
+ *
+ */
+static void isci_remote_device_deconstruct(struct isci_host *ihost, struct isci_remote_device *idev)
+{
+       dev_dbg(&ihost->pdev->dev,
+               "%s: isci_device = %p\n", __func__, idev);
+
+       /* There should not be any outstanding io's. All paths to
+        * here should go through isci_remote_device_nuke_requests.
+        * If we hit this condition, we will need a way to complete
+        * io requests in process */
+       BUG_ON(idev->started_request_count > 0);
+
+       sci_remote_device_destruct(idev);
+       list_del_init(&idev->node);
+       isci_put_device(idev);
+}
+
+static void sci_remote_device_stopped_state_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+       u32 prev_state;
+
+       /* If we are entering from the stopping state let the SCI User know that
+        * the stop operation has completed.
+        */
+       prev_state = idev->sm.previous_state_id;
+       if (prev_state == SCI_DEV_STOPPING)
+               isci_remote_device_deconstruct(ihost, idev);
+
+       sci_controller_remote_device_stopped(ihost, idev);
+}
+
+static void sci_remote_device_starting_state_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       isci_remote_device_not_ready(ihost, idev,
+                                    SCIC_REMOTE_DEVICE_NOT_READY_START_REQUESTED);
+}
+
+static void sci_remote_device_ready_state_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+       struct domain_device *dev = idev->domain_dev;
+
+       if (dev->dev_type == SAS_SATA_DEV || (dev->tproto & SAS_PROTOCOL_SATA)) {
+               sci_change_state(&idev->sm, SCI_STP_DEV_IDLE);
+       } else if (dev_is_expander(dev)) {
+               sci_change_state(&idev->sm, SCI_SMP_DEV_IDLE);
+       } else
+               isci_remote_device_ready(ihost, idev);
+}
+
+static void sci_remote_device_ready_state_exit(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct domain_device *dev = idev->domain_dev;
+
+       if (dev->dev_type == SAS_END_DEVICE) {
+               struct isci_host *ihost = idev->owning_port->owning_controller;
+
+               isci_remote_device_not_ready(ihost, idev,
+                                            SCIC_REMOTE_DEVICE_NOT_READY_STOP_REQUESTED);
+       }
+}
+
+static void sci_remote_device_resetting_state_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       dev_dbg(&ihost->pdev->dev,
+               "%s: isci_device = %p\n", __func__, idev);
+
+       sci_remote_device_suspend(idev, SCI_SW_SUSPEND_LINKHANG_DETECT);
+}
+
+static void sci_remote_device_resetting_state_exit(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       dev_dbg(&ihost->pdev->dev,
+               "%s: isci_device = %p\n", __func__, idev);
+
+       sci_remote_node_context_resume(&idev->rnc, NULL, NULL);
+}
+
+static void sci_stp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+
+       idev->working_request = NULL;
+       if (sci_remote_node_context_is_ready(&idev->rnc)) {
+               /*
+                * Since the RNC is ready, it's alright to finish completion
+                * processing (e.g. signal the remote device is ready). */
+               sci_stp_remote_device_ready_idle_substate_resume_complete_handler(idev);
+       } else {
+               sci_remote_node_context_resume(&idev->rnc,
+                       sci_stp_remote_device_ready_idle_substate_resume_complete_handler,
+                       idev);
+       }
+}
+
+static void sci_stp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       BUG_ON(idev->working_request == NULL);
+
+       isci_remote_device_not_ready(ihost, idev,
+                                    SCIC_REMOTE_DEVICE_NOT_READY_SATA_REQUEST_STARTED);
+}
+
+static void sci_stp_remote_device_ready_ncq_error_substate_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       if (idev->not_ready_reason == SCIC_REMOTE_DEVICE_NOT_READY_SATA_SDB_ERROR_FIS_RECEIVED)
+               isci_remote_device_not_ready(ihost, idev,
+                                            idev->not_ready_reason);
+}
+
+static void sci_smp_remote_device_ready_idle_substate_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       isci_remote_device_ready(ihost, idev);
+}
+
+static void sci_smp_remote_device_ready_cmd_substate_enter(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+
+       BUG_ON(idev->working_request == NULL);
+
+       isci_remote_device_not_ready(ihost, idev,
+                                    SCIC_REMOTE_DEVICE_NOT_READY_SMP_REQUEST_STARTED);
+}
+
+static void sci_smp_remote_device_ready_cmd_substate_exit(struct sci_base_state_machine *sm)
+{
+       struct isci_remote_device *idev = container_of(sm, typeof(*idev), sm);
+
+       idev->working_request = NULL;
+}
+
+static const struct sci_base_state sci_remote_device_state_table[] = {
+       [SCI_DEV_INITIAL] = {
+               .enter_state = sci_remote_device_initial_state_enter,
+       },
+       [SCI_DEV_STOPPED] = {
+               .enter_state = sci_remote_device_stopped_state_enter,
+       },
+       [SCI_DEV_STARTING] = {
+               .enter_state = sci_remote_device_starting_state_enter,
+       },
+       [SCI_DEV_READY] = {
+               .enter_state = sci_remote_device_ready_state_enter,
+               .exit_state  = sci_remote_device_ready_state_exit
+       },
+       [SCI_STP_DEV_IDLE] = {
+               .enter_state = sci_stp_remote_device_ready_idle_substate_enter,
+       },
+       [SCI_STP_DEV_CMD] = {
+               .enter_state = sci_stp_remote_device_ready_cmd_substate_enter,
+       },
+       [SCI_STP_DEV_NCQ] = { },
+       [SCI_STP_DEV_NCQ_ERROR] = {
+               .enter_state = sci_stp_remote_device_ready_ncq_error_substate_enter,
+       },
+       [SCI_STP_DEV_ATAPI_ERROR] = { },
+       [SCI_STP_DEV_AWAIT_RESET] = { },
+       [SCI_SMP_DEV_IDLE] = {
+               .enter_state = sci_smp_remote_device_ready_idle_substate_enter,
+       },
+       [SCI_SMP_DEV_CMD] = {
+               .enter_state = sci_smp_remote_device_ready_cmd_substate_enter,
+               .exit_state  = sci_smp_remote_device_ready_cmd_substate_exit,
+       },
+       [SCI_DEV_STOPPING] = { },
+       [SCI_DEV_FAILED] = { },
+       [SCI_DEV_RESETTING] = {
+               .enter_state = sci_remote_device_resetting_state_enter,
+               .exit_state  = sci_remote_device_resetting_state_exit
+       },
+       [SCI_DEV_FINAL] = { },
+};
+
+/**
+ * sci_remote_device_construct() - common construction
+ * @sci_port: SAS/SATA port through which this device is accessed.
+ * @sci_dev: remote device to construct
+ *
+ * This routine just performs benign initialization and does not
+ * allocate the remote_node_context which is left to
+ * sci_remote_device_[de]a_construct().  sci_remote_device_destruct()
+ * frees the remote_node_context(s) for the device.
+ */
+static void sci_remote_device_construct(struct isci_port *iport,
+                                 struct isci_remote_device *idev)
+{
+       idev->owning_port = iport;
+       idev->started_request_count = 0;
+
+       sci_init_sm(&idev->sm, sci_remote_device_state_table, SCI_DEV_INITIAL);
+
+       sci_remote_node_context_construct(&idev->rnc,
+                                              SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX);
+}
+
+/**
+ * sci_remote_device_da_construct() - construct direct attached device.
+ *
+ * The information (e.g. IAF, Signature FIS, etc.) necessary to build
+ * the device is known to the SCI Core since it is contained in the
+ * sci_phy object.  Remote node context(s) is/are a global resource
+ * allocated by this routine, freed by sci_remote_device_destruct().
+ *
+ * Returns:
+ * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
+ * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
+ * sata-only controller instance.
+ * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
+ */
+static enum sci_status sci_remote_device_da_construct(struct isci_port *iport,
+                                                      struct isci_remote_device *idev)
+{
+       enum sci_status status;
+       struct sci_port_properties properties;
+
+       sci_remote_device_construct(iport, idev);
+
+       sci_port_get_properties(iport, &properties);
+       /* Get accurate port width from port's phy mask for a DA device. */
+       idev->device_port_width = hweight32(properties.phy_mask);
+
+       status = sci_controller_allocate_remote_node_context(iport->owning_controller,
+                                                            idev,
+                                                            &idev->rnc.remote_node_index);
+
+       if (status != SCI_SUCCESS)
+               return status;
+
+       idev->connection_rate = sci_port_get_max_allowed_speed(iport);
+
+       return SCI_SUCCESS;
+}
+
+/**
+ * sci_remote_device_ea_construct() - construct expander attached device
+ *
+ * Remote node context(s) is/are a global resource allocated by this
+ * routine, freed by sci_remote_device_destruct().
+ *
+ * Returns:
+ * SCI_FAILURE_DEVICE_EXISTS - device has already been constructed.
+ * SCI_FAILURE_UNSUPPORTED_PROTOCOL - e.g. sas device attached to
+ * sata-only controller instance.
+ * SCI_FAILURE_INSUFFICIENT_RESOURCES - remote node contexts exhausted.
+ */
+static enum sci_status sci_remote_device_ea_construct(struct isci_port *iport,
+                                                      struct isci_remote_device *idev)
+{
+       struct domain_device *dev = idev->domain_dev;
+       enum sci_status status;
+
+       sci_remote_device_construct(iport, idev);
+
+       status = sci_controller_allocate_remote_node_context(iport->owning_controller,
+                                                                 idev,
+                                                                 &idev->rnc.remote_node_index);
+       if (status != SCI_SUCCESS)
+               return status;
+
+       /* For SAS-2 the physical link rate is actually a logical link
+        * rate that incorporates multiplexing.  The SCU doesn't
+        * incorporate multiplexing and for the purposes of the
+        * connection the logical link rate is that same as the
+        * physical.  Furthermore, the SAS-2 and SAS-1.1 fields overlay
+        * one another, so this code works for both situations.
+        */
+       idev->connection_rate = min_t(u16, sci_port_get_max_allowed_speed(iport),
+                                        dev->linkrate);
+
+       /* / @todo Should I assign the port width by reading all of the phys on the port? */
+       idev->device_port_width = 1;
+
+       return SCI_SUCCESS;
+}
+
+enum sci_status sci_remote_device_resume(
+       struct isci_remote_device *idev,
+       scics_sds_remote_node_context_callback cb_fn,
+       void *cb_p)
+{
+       enum sci_status status;
+
+       status = sci_remote_node_context_resume(&idev->rnc, cb_fn, cb_p);
+       if (status != SCI_SUCCESS)
+               dev_dbg(scirdev_to_dev(idev), "%s: failed to resume: %d\n",
+                       __func__, status);
+       return status;
+}
+
+static void isci_remote_device_resume_from_abort_complete(void *cbparam)
+{
+       struct isci_remote_device *idev = cbparam;
+       struct isci_host *ihost = idev->owning_port->owning_controller;
+       scics_sds_remote_node_context_callback abort_resume_cb =
+               idev->abort_resume_cb;
+
+       dev_dbg(scirdev_to_dev(idev), "%s: passing-along resume: %p\n",
+               __func__, abort_resume_cb);
+
+       if (abort_resume_cb != NULL) {
+               idev->abort_resume_cb = NULL;
+               abort_resume_cb(idev->abort_resume_cbparam);
+       }
+       clear_bit(IDEV_ABORT_PATH_RESUME_PENDING, &idev->flags);
+       wake_up(&ihost->eventq);
+}
+
+static bool isci_remote_device_test_resume_done(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev)
+{
+       unsigned long flags;
+       bool done;
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       done = !test_bit(IDEV_ABORT_PATH_RESUME_PENDING, &idev->flags)
+               || test_bit(IDEV_STOP_PENDING, &idev->flags)
+               || sci_remote_node_context_is_being_destroyed(&idev->rnc);
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+       return done;
+}
+
+void isci_remote_device_wait_for_resume_from_abort(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev)
+{
+       dev_dbg(&ihost->pdev->dev, "%s: starting resume wait: %p\n",
+                __func__, idev);
+
+       #define MAX_RESUME_MSECS 10000
+       if (!wait_event_timeout(ihost->eventq,
+                               isci_remote_device_test_resume_done(ihost, idev),
+                               msecs_to_jiffies(MAX_RESUME_MSECS))) {
+
+               dev_warn(&ihost->pdev->dev, "%s: #### Timeout waiting for "
+                        "resume: %p\n", __func__, idev);
+       }
+       clear_bit(IDEV_ABORT_PATH_RESUME_PENDING, &idev->flags);
+
+       dev_dbg(&ihost->pdev->dev, "%s: resume wait done: %p\n",
+                __func__, idev);
+}
+
+enum sci_status isci_remote_device_resume_from_abort(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev)
+{
+       unsigned long flags;
+       enum sci_status status = SCI_SUCCESS;
+       int destroyed;
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       /* Preserve any current resume callbacks, for instance from other
+        * resumptions.
+        */
+       idev->abort_resume_cb = idev->rnc.user_callback;
+       idev->abort_resume_cbparam = idev->rnc.user_cookie;
+       set_bit(IDEV_ABORT_PATH_RESUME_PENDING, &idev->flags);
+       clear_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags);
+       destroyed = sci_remote_node_context_is_being_destroyed(&idev->rnc);
+       if (!destroyed)
+               status = sci_remote_device_resume(
+                       idev, isci_remote_device_resume_from_abort_complete,
+                       idev);
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+       if (!destroyed && (status == SCI_SUCCESS))
+               isci_remote_device_wait_for_resume_from_abort(ihost, idev);
+       else
+               clear_bit(IDEV_ABORT_PATH_RESUME_PENDING, &idev->flags);
+
+       return status;
+}
+
+/**
+ * sci_remote_device_start() - This method will start the supplied remote
+ *    device.  This method enables normal IO requests to flow through to the
+ *    remote device.
+ * @remote_device: This parameter specifies the device to be started.
+ * @timeout: This parameter specifies the number of milliseconds in which the
+ *    start operation should complete.
+ *
+ * An indication of whether the device was successfully started. SCI_SUCCESS
+ * This value is returned if the device was successfully started.
+ * SCI_FAILURE_INVALID_PHY This value is returned if the user attempts to start
+ * the device when there have been no phys added to it.
+ */
+static enum sci_status sci_remote_device_start(struct isci_remote_device *idev,
+                                              u32 timeout)
+{
+       struct sci_base_state_machine *sm = &idev->sm;
+       enum sci_remote_device_states state = sm->current_state_id;
+       enum sci_status status;
+
+       if (state != SCI_DEV_STOPPED) {
+               dev_warn(scirdev_to_dev(idev), "%s: in wrong state: %s\n",
+                        __func__, dev_state_name(state));
+               return SCI_FAILURE_INVALID_STATE;
+       }
+
+       status = sci_remote_device_resume(idev, remote_device_resume_done,
+                                         idev);
+       if (status != SCI_SUCCESS)
+               return status;
+
+       sci_change_state(sm, SCI_DEV_STARTING);
+
+       return SCI_SUCCESS;
+}
+
+static enum sci_status isci_remote_device_construct(struct isci_port *iport,
+                                                   struct isci_remote_device *idev)
+{
+       struct isci_host *ihost = iport->isci_host;
+       struct domain_device *dev = idev->domain_dev;
+       enum sci_status status;
+
+       if (dev->parent && dev_is_expander(dev->parent))
+               status = sci_remote_device_ea_construct(iport, idev);
+       else
+               status = sci_remote_device_da_construct(iport, idev);
+
+       if (status != SCI_SUCCESS) {
+               dev_dbg(&ihost->pdev->dev, "%s: construct failed: %d\n",
+                       __func__, status);
+
+               return status;
+       }
+
+       /* start the device. */
+       status = sci_remote_device_start(idev, ISCI_REMOTE_DEVICE_START_TIMEOUT);
+
+       if (status != SCI_SUCCESS)
+               dev_warn(&ihost->pdev->dev, "remote device start failed: %d\n",
+                        status);
+
+       return status;
+}
+
+/**
+ * This function builds the isci_remote_device when a libsas dev_found message
+ *    is received.
+ * @isci_host: This parameter specifies the isci host object.
+ * @port: This parameter specifies the isci_port conected to this device.
+ *
+ * pointer to new isci_remote_device.
+ */
+static struct isci_remote_device *
+isci_remote_device_alloc(struct isci_host *ihost, struct isci_port *iport)
+{
+       struct isci_remote_device *idev;
+       int i;
+
+       for (i = 0; i < SCI_MAX_REMOTE_DEVICES; i++) {
+               idev = &ihost->devices[i];
+               if (!test_and_set_bit(IDEV_ALLOCATED, &idev->flags))
+                       break;
+       }
+
+       if (i >= SCI_MAX_REMOTE_DEVICES) {
+               dev_warn(&ihost->pdev->dev, "%s: failed\n", __func__);
+               return NULL;
+       }
+       if (WARN_ONCE(!list_empty(&idev->node), "found non-idle remote device\n"))
+               return NULL;
+
+       return idev;
+}
+
+void isci_remote_device_release(struct kref *kref)
+{
+       struct isci_remote_device *idev = container_of(kref, typeof(*idev), kref);
+       struct isci_host *ihost = idev->isci_port->isci_host;
+
+       idev->domain_dev = NULL;
+       idev->isci_port = NULL;
+       clear_bit(IDEV_START_PENDING, &idev->flags);
+       clear_bit(IDEV_STOP_PENDING, &idev->flags);
+       clear_bit(IDEV_IO_READY, &idev->flags);
+       clear_bit(IDEV_GONE, &idev->flags);
+       smp_mb__before_atomic();
+       clear_bit(IDEV_ALLOCATED, &idev->flags);
+       wake_up(&ihost->eventq);
+}
+
+/**
+ * isci_remote_device_stop() - This function is called internally to stop the
+ *    remote device.
+ * @isci_host: This parameter specifies the isci host object.
+ * @isci_device: This parameter specifies the remote device.
+ *
+ * The status of the ihost request to stop.
+ */
+enum sci_status isci_remote_device_stop(struct isci_host *ihost, struct isci_remote_device *idev)
+{
+       enum sci_status status;
+       unsigned long flags;
+
+       dev_dbg(&ihost->pdev->dev,
+               "%s: isci_device = %p\n", __func__, idev);
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       idev->domain_dev->lldd_dev = NULL; /* disable new lookups */
+       set_bit(IDEV_GONE, &idev->flags);
+
+       set_bit(IDEV_STOP_PENDING, &idev->flags);
+       status = sci_remote_device_stop(idev, 50);
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+       /* Wait for the stop complete callback. */
+       if (WARN_ONCE(status != SCI_SUCCESS, "failed to stop device\n"))
+               /* nothing to wait for */;
+       else
+               wait_for_device_stop(ihost, idev);
+
+       dev_dbg(&ihost->pdev->dev,
+               "%s: isci_device = %p, waiting done.\n", __func__, idev);
+
+       return status;
+}
+
+/**
+ * isci_remote_device_gone() - This function is called by libsas when a domain
+ *    device is removed.
+ * @domain_device: This parameter specifies the libsas domain device.
+ *
+ */
+void isci_remote_device_gone(struct domain_device *dev)
+{
+       struct isci_host *ihost = dev_to_ihost(dev);
+       struct isci_remote_device *idev = dev->lldd_dev;
+
+       dev_dbg(&ihost->pdev->dev,
+               "%s: domain_device = %p, isci_device = %p, isci_port = %p\n",
+               __func__, dev, idev, idev->isci_port);
+
+       isci_remote_device_stop(ihost, idev);
+}
+
+
+/**
+ * isci_remote_device_found() - This function is called by libsas when a remote
+ *    device is discovered. A remote device object is created and started. the
+ *    function then sleeps until the sci core device started message is
+ *    received.
+ * @domain_device: This parameter specifies the libsas domain device.
+ *
+ * status, zero indicates success.
+ */
+int isci_remote_device_found(struct domain_device *dev)
+{
+       struct isci_host *isci_host = dev_to_ihost(dev);
+       struct isci_port *isci_port = dev->port->lldd_port;
+       struct isci_remote_device *isci_device;
+       enum sci_status status;
+
+       dev_dbg(&isci_host->pdev->dev,
+               "%s: domain_device = %p\n", __func__, dev);
+
+       if (!isci_port)
+               return -ENODEV;
+
+       isci_device = isci_remote_device_alloc(isci_host, isci_port);
+       if (!isci_device)
+               return -ENODEV;
+
+       kref_init(&isci_device->kref);
+       INIT_LIST_HEAD(&isci_device->node);
+
+       spin_lock_irq(&isci_host->scic_lock);
+       isci_device->domain_dev = dev;
+       isci_device->isci_port = isci_port;
+       list_add_tail(&isci_device->node, &isci_port->remote_dev_list);
+
+       set_bit(IDEV_START_PENDING, &isci_device->flags);
+       status = isci_remote_device_construct(isci_port, isci_device);
+
+       dev_dbg(&isci_host->pdev->dev,
+               "%s: isci_device = %p\n",
+               __func__, isci_device);
+
+       if (status == SCI_SUCCESS) {
+               /* device came up, advertise it to the world */
+               dev->lldd_dev = isci_device;
+       } else
+               isci_put_device(isci_device);
+       spin_unlock_irq(&isci_host->scic_lock);
+
+       /* wait for the device ready callback. */
+       wait_for_device_start(isci_host, isci_device);
+
+       return status == SCI_SUCCESS ? 0 : -ENODEV;
+}
+
+enum sci_status isci_remote_device_suspend_terminate(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev,
+       struct isci_request *ireq)
+{
+       unsigned long flags;
+       enum sci_status status;
+
+       /* Put the device into suspension. */
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       set_bit(IDEV_ABORT_PATH_ACTIVE, &idev->flags);
+       sci_remote_device_suspend(idev, SCI_SW_SUSPEND_LINKHANG_DETECT);
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+       /* Terminate and wait for the completions. */
+       status = isci_remote_device_terminate_requests(ihost, idev, ireq);
+       if (status != SCI_SUCCESS)
+               dev_dbg(&ihost->pdev->dev,
+                       "%s: isci_remote_device_terminate_requests(%p) "
+                               "returned %d!\n",
+                       __func__, idev, status);
+
+       /* NOTE: RNC resumption is left to the caller! */
+       return status;
+}
+
+int isci_remote_device_is_safe_to_abort(
+       struct isci_remote_device *idev)
+{
+       return sci_remote_node_context_is_safe_to_abort(&idev->rnc);
+}
+
+enum sci_status sci_remote_device_abort_requests_pending_abort(
+       struct isci_remote_device *idev)
+{
+       return sci_remote_device_terminate_reqs_checkabort(idev, 1);
+}
+
+enum sci_status isci_remote_device_reset_complete(
+       struct isci_host *ihost,
+       struct isci_remote_device *idev)
+{
+       unsigned long flags;
+       enum sci_status status;
+
+       spin_lock_irqsave(&ihost->scic_lock, flags);
+       status = sci_remote_device_reset_complete(idev);
+       spin_unlock_irqrestore(&ihost->scic_lock, flags);
+
+       return status;
+}
+
+void isci_dev_set_hang_detection_timeout(
+       struct isci_remote_device *idev,
+       u32 timeout)
+{
+       if (dev_is_sata(idev->domain_dev)) {
+               if (timeout) {
+                       if (test_and_set_bit(IDEV_RNC_LLHANG_ENABLED,
+                                            &idev->flags))
+                               return;  /* Already enabled. */
+               } else if (!test_and_clear_bit(IDEV_RNC_LLHANG_ENABLED,
+                                              &idev->flags))
+                       return;  /* Not enabled. */
+
+               sci_port_set_hang_detection_timeout(idev->owning_port,
+                                                   timeout);
+       }
+}