[SCSI] mpt2sas: No link rate change, do not call update links nor unblock device

(1) target resets are sending link change rate events with no link rate
change -> thus said the driver was modified so when there is no link rate
change, we don't need to call mpt2sas_transport_update_links nor
_scsih_ublock_io_device.
(2) There were changes made in _scsih_sas_topology_change_event_debug to
change the debug strings so they are more clear.  Also the link rate change
information was added to display the new and previous link rate.
for the MPI2_EVENT_SAS_TOPOLOGY_CHANGE_LIST event when the ExpStatus is
set to zero, display "responding" instead of "unknown status".

Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: Eric Moore <Eric.moore@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 27 insertions, 25 deletions

diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index 5916bddf3551..8dc682f00fd2 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -2380,7 +2380,6 @@ _scsih_block_io_to_children_attached_directly(struct MPT2SAS_ADAPTER *ioc,
         u16 handle;
         u16 reason_code;
         u8 phy_number;
-        u8 link_rate;
 
         for (i = 0; i < event_data->NumEntries; i++) {
                 handle = le16_to_cpu(event_data->PHY[i].AttachedDevHandle);
@@ -2391,11 +2390,6 @@ _scsih_block_io_to_children_attached_directly(struct MPT2SAS_ADAPTER *ioc,
                     MPI2_EVENT_SAS_TOPO_RC_MASK;
                 if (reason_code == MPI2_EVENT_SAS_TOPO_RC_DELAY_NOT_RESPONDING)
                         _scsih_block_io_device(ioc, handle);
-                if (reason_code == MPI2_EVENT_SAS_TOPO_RC_PHY_CHANGED) {
-                        link_rate = event_data->PHY[i].LinkRate >> 4;
-                        if (link_rate >= MPI2_SAS_NEG_LINK_RATE_1_5)
-                                _scsih_ublock_io_device(ioc, handle);
-                }
         }
 }
 
@@ -4084,7 +4078,7 @@ _scsih_sas_topology_change_event_debug(struct MPT2SAS_ADAPTER *ioc,
         u16 reason_code;
         u8 phy_number;
         char *status_str = NULL;
-        char link_rate[25];
+        u8 link_rate, prev_link_rate;
 
         switch (event_data->ExpStatus) {
         case MPI2_EVENT_SAS_TOPO_ES_ADDED:
@@ -4094,6 +4088,7 @@ _scsih_sas_topology_change_event_debug(struct MPT2SAS_ADAPTER *ioc,
                 status_str = "remove";
                 break;
         case MPI2_EVENT_SAS_TOPO_ES_RESPONDING:
+        case 0:
                 status_str =  "responding";
                 break;
         case MPI2_EVENT_SAS_TOPO_ES_DELAY_NOT_RESPONDING:
@@ -4119,30 +4114,30 @@ _scsih_sas_topology_change_event_debug(struct MPT2SAS_ADAPTER *ioc,
                     MPI2_EVENT_SAS_TOPO_RC_MASK;
                 switch (reason_code) {
                 case MPI2_EVENT_SAS_TOPO_RC_TARG_ADDED:
-                        snprintf(link_rate, 25, ": add, link(0x%02x)",
-                            (event_data->PHY[i].LinkRate >> 4));
-                        status_str = link_rate;
+                        status_str = "target add";
                         break;
                 case MPI2_EVENT_SAS_TOPO_RC_TARG_NOT_RESPONDING:
-                        status_str = ": remove";
+                        status_str = "target remove";
                         break;
                 case MPI2_EVENT_SAS_TOPO_RC_DELAY_NOT_RESPONDING:
-                        status_str = ": remove_delay";
+                        status_str = "delay target remove";
                         break;
                 case MPI2_EVENT_SAS_TOPO_RC_PHY_CHANGED:
-                        snprintf(link_rate, 25, ": link(0x%02x)",
-                            (event_data->PHY[i].LinkRate >> 4));
-                        status_str = link_rate;
+                        status_str = "link rate change";
                         break;
                 case MPI2_EVENT_SAS_TOPO_RC_NO_CHANGE:
-                        status_str = ": responding";
+                        status_str = "target responding";
                         break;
                 default:
-                        status_str = ": unknown";
+                        status_str = "unknown";
                         break;
                 }
-                printk(KERN_DEBUG "\tphy(%02d), attached_handle(0x%04x)%s\n",
-                    phy_number, handle, status_str);
+                link_rate = event_data->PHY[i].LinkRate >> 4;
+                prev_link_rate = event_data->PHY[i].LinkRate & 0xF;
+                printk(KERN_DEBUG "\tphy(%02d), attached_handle(0x%04x): %s:"
+                    " link rate: new(0x%02x), old(0x%02x)\n", phy_number,
+                    handle, status_str, link_rate, prev_link_rate);
+
         }
 }
 #endif
@@ -4166,7 +4161,7 @@ _scsih_sas_topology_change_event(struct MPT2SAS_ADAPTER *ioc,
         struct _sas_device *sas_device;
         u64 sas_address;
         unsigned long flags;
-        u8 link_rate;
+        u8 link_rate, prev_link_rate;
         Mpi2EventDataSasTopologyChangeList_t *event_data = fw_event->event_data;
 
 #ifdef CONFIG_SCSI_MPT2SAS_LOGGING
@@ -4226,18 +4221,25 @@ _scsih_sas_topology_change_event(struct MPT2SAS_ADAPTER *ioc,
                 if (!handle)
                         continue;
                 link_rate = event_data->PHY[i].LinkRate >> 4;
+                prev_link_rate = event_data->PHY[i].LinkRate & 0xF;
                 switch (reason_code) {
                 case MPI2_EVENT_SAS_TOPO_RC_PHY_CHANGED:
+
+                        if (link_rate == prev_link_rate)
+                                break;
+
+                        mpt2sas_transport_update_links(ioc, sas_address,
+                            handle, phy_number, link_rate);
+
+                        if (link_rate >= MPI2_SAS_NEG_LINK_RATE_1_5)
+                                _scsih_ublock_io_device(ioc, handle);
+                        break;
                 case MPI2_EVENT_SAS_TOPO_RC_TARG_ADDED:
 
                         mpt2sas_transport_update_links(ioc, sas_address,
                             handle, phy_number, link_rate);
 
-                        if (link_rate < MPI2_SAS_NEG_LINK_RATE_1_5)
-                                break;
-                        if (reason_code == MPI2_EVENT_SAS_TOPO_RC_TARG_ADDED) {
-                                _scsih_add_device(ioc, handle, phy_number, 0);
-                        }
+                        _scsih_add_device(ioc, handle, phy_number, 0);
                         break;
                 case MPI2_EVENT_SAS_TOPO_RC_TARG_NOT_RESPONDING: