isci: fix controller stop

1/ notify waiters when controller stop completes (fixes 10 second stall
   unloading the driver)
2/ make sure phy stop is after port and device stop

Cc: Richard Boyd <richard.g.boyd@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

2 files changed, 55 insertions, 52 deletions

diff --git a/drivers/scsi/isci/host.c b/drivers/scsi/isci/host.c
index 0fe372f93289..95c3da66ea4b 100644
--- a/drivers/scsi/isci/host.c
+++ b/drivers/scsi/isci/host.c
@@ -1046,7 +1046,7 @@ void isci_host_scan_start(struct Scsi_Host *shost)
         spin_unlock_irq(&ihost->scic_lock);
 }
 
-static void isci_host_stop_complete(struct isci_host *ihost, enum sci_status completion_status)
+static void isci_host_stop_complete(struct isci_host *ihost)
 {
         sci_controller_disable_interrupts(ihost);
         clear_bit(IHOST_STOP_PENDING, &ihost->flags);
@@ -1232,7 +1232,7 @@ static enum sci_status sci_controller_reset(struct isci_host *ihost)
         switch (ihost->sm.current_state_id) {
         case SCIC_RESET:
         case SCIC_READY:
-        case SCIC_STOPPED:
+        case SCIC_STOPPING:
         case SCIC_FAILED:
                 /*
                  * The reset operation is not a graceful cleanup, just
@@ -1247,6 +1247,44 @@ static enum sci_status sci_controller_reset(struct isci_host *ihost)
         }
 }
 
+static enum sci_status sci_controller_stop_phys(struct isci_host *ihost)
+{
+        u32 index;
+        enum sci_status status;
+        enum sci_status phy_status;
+
+        status = SCI_SUCCESS;
+
+        for (index = 0; index < SCI_MAX_PHYS; index++) {
+                phy_status = sci_phy_stop(&ihost->phys[index]);
+
+                if (phy_status != SCI_SUCCESS &&
+                    phy_status != SCI_FAILURE_INVALID_STATE) {
+                        status = SCI_FAILURE;
+
+                        dev_warn(&ihost->pdev->dev,
+                                 "%s: Controller stop operation failed to stop "
+                                 "phy %d because of status %d.\n",
+                                 __func__,
+                                 ihost->phys[index].phy_index, phy_status);
+                }
+        }
+
+        return status;
+}
+
+
+/**
+ * isci_host_deinit - shutdown frame reception and dma
+ * @ihost: host to take down
+ *
+ * This is called in either the driver shutdown or the suspend path.  In
+ * the shutdown case libsas went through port teardown and normal device
+ * removal (i.e. physical links stayed up to service scsi_device removal
+ * commands).  In the suspend case we disable the hardware without
+ * notifying libsas of the link down events since we want libsas to
+ * remember the domain across the suspend/resume cycle
+ */
 void isci_host_deinit(struct isci_host *ihost)
 {
         int i;
@@ -1255,16 +1293,6 @@ void isci_host_deinit(struct isci_host *ihost)
         for (i = 0; i < isci_gpio_count(ihost); i++)
                 writel(SGPIO_HW_CONTROL, &ihost->scu_registers->peg0.sgpio.output_data_select[i]);
 
-        for (i = 0; i < SCI_MAX_PORTS; i++) {
-                struct isci_port *iport = &ihost->ports[i];
-                struct isci_remote_device *idev, *d;
-
-                list_for_each_entry_safe(idev, d, &iport->remote_dev_list, node) {
-                        if (test_bit(IDEV_ALLOCATED, &idev->flags))
-                                isci_remote_device_stop(ihost, idev);
-                }
-        }
-
         set_bit(IHOST_STOP_PENDING, &ihost->flags);
 
         spin_lock_irq(&ihost->scic_lock);
@@ -1273,6 +1301,13 @@ void isci_host_deinit(struct isci_host *ihost)
 
         wait_for_stop(ihost);
 
+        /* phy stop is after controller stop to allow port and device to
+         * go idle before shutting down the phys, but the expectation is
+         * that i/o has been shut off well before we reach this
+         * function.
+         */
+        sci_controller_stop_phys(ihost);
+
         /* disable sgpio: where the above wait should give time for the
          * enclosure to sample the gpios going inactive
          */
@@ -1476,32 +1511,6 @@ static void sci_controller_ready_state_exit(struct sci_base_state_machine *sm)
         sci_controller_set_interrupt_coalescence(ihost, 0, 0);
 }
 
-static enum sci_status sci_controller_stop_phys(struct isci_host *ihost)
-{
-        u32 index;
-        enum sci_status status;
-        enum sci_status phy_status;
-
-        status = SCI_SUCCESS;
-
-        for (index = 0; index < SCI_MAX_PHYS; index++) {
-                phy_status = sci_phy_stop(&ihost->phys[index]);
-
-                if (phy_status != SCI_SUCCESS &&
-                    phy_status != SCI_FAILURE_INVALID_STATE) {
-                        status = SCI_FAILURE;
-
-                        dev_warn(&ihost->pdev->dev,
-                                 "%s: Controller stop operation failed to stop "
-                                 "phy %d because of status %d.\n",
-                                 __func__,
-                                 ihost->phys[index].phy_index, phy_status);
-                }
-        }
-
-        return status;
-}
-
 static enum sci_status sci_controller_stop_ports(struct isci_host *ihost)
 {
         u32 index;
@@ -1561,10 +1570,11 @@ static void sci_controller_stopping_state_enter(struct sci_base_state_machine *s
 {
         struct isci_host *ihost = container_of(sm, typeof(*ihost), sm);
 
-        /* Stop all of the components for this controller */
-        sci_controller_stop_phys(ihost);
-        sci_controller_stop_ports(ihost);
         sci_controller_stop_devices(ihost);
+        sci_controller_stop_ports(ihost);
+
+        if (!sci_controller_has_remote_devices_stopping(ihost))
+                isci_host_stop_complete(ihost);
 }
 
 static void sci_controller_stopping_state_exit(struct sci_base_state_machine *sm)
@@ -1621,7 +1631,6 @@ static const struct sci_base_state sci_controller_state_table[] = {
                 .enter_state = sci_controller_stopping_state_enter,
                 .exit_state = sci_controller_stopping_state_exit,
         },
-        [SCIC_STOPPED] = {},
         [SCIC_FAILED] = {}
 };
 
@@ -1641,7 +1650,7 @@ static void controller_timeout(unsigned long data)
                 sci_controller_transition_to_ready(ihost, SCI_FAILURE_TIMEOUT);
         else if (sm->current_state_id == SCIC_STOPPING) {
                 sci_change_state(sm, SCIC_FAILED);
-                isci_host_stop_complete(ihost, SCI_FAILURE_TIMEOUT);
+                isci_host_stop_complete(ihost);
         } else  /* / @todo Now what do we want to do in this case? */
                 dev_err(&ihost->pdev->dev,
                         "%s: Controller timer fired when controller was not "
@@ -2452,7 +2461,7 @@ void sci_controller_link_down(struct isci_host *ihost, struct isci_port *iport,
         }
 }
 
-static bool sci_controller_has_remote_devices_stopping(struct isci_host *ihost)
+bool sci_controller_has_remote_devices_stopping(struct isci_host *ihost)
 {
         u32 index;
 
@@ -2478,7 +2487,7 @@ void sci_controller_remote_device_stopped(struct isci_host *ihost,
         }
 
         if (!sci_controller_has_remote_devices_stopping(ihost))
-                sci_change_state(&ihost->sm, SCIC_STOPPED);
+                isci_host_stop_complete(ihost);
 }
 
 void sci_controller_post_request(struct isci_host *ihost, u32 request)
diff --git a/drivers/scsi/isci/host.h b/drivers/scsi/isci/host.h
index 4695162f406e..a89c0e3c5a14 100644
--- a/drivers/scsi/isci/host.h
+++ b/drivers/scsi/isci/host.h
@@ -277,13 +277,6 @@ enum sci_controller_states {
         SCIC_STOPPING,
 
         /**
-         * This state indicates that the controller has successfully been stopped.
-         * In this state no new IO operations are permitted.
-         * This state is entered from the STOPPING state.
-         */
-        SCIC_STOPPED,
-
-        /**
          * This state indicates that the controller could not successfully be
          * initialized.  In this state no new IO operations are permitted.
          * This state is entered from the INITIALIZING state.
@@ -479,6 +472,7 @@ int isci_host_init(struct isci_host *);
 void isci_host_completion_routine(unsigned long data);
 void isci_host_deinit(struct isci_host *);
 void sci_controller_disable_interrupts(struct isci_host *ihost);
+bool sci_controller_has_remote_devices_stopping(struct isci_host *ihost);
 
 enum sci_status sci_controller_start_io(
         struct isci_host *ihost,