megaraid_sas: Don't issue kill adapter for MFI controllers in case of PD list DCMD failure

There are few MFI adapters which do not support MR_DCMD_PD_LIST_QUERY so
if MFI adapters fail this DCMD, it should not be considered as FATAL and
driver should not issue kill adapter and set per controller's instance
variable- pd_list_not_supported so that same variable can be used inside
functions- slave_alloc and slave_configure to allow firmware scan.

Killing adapter because of DCMD failure when this DCMD is not supported
causes driver's probe getting failed. This issue got introduced by
commit 6d40afbc7d13 ("megaraid_sas: MFI IO timeout handling").

Killing adapter in case of this DCMD failure should be limited to Fusion
adapters only. Per controller's instance variable allow_fw_scan is
removed as pd_list_not_supported better reflect the purpose.

Fixes: 6d40afbc7d13359b30a5cd783e3db6ebefa5f40a
Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinicke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/megaraid/megaraid_sas.h

@@ -2097,7 +2097,7 @@ struct megasas_instance {
 	u8 UnevenSpanSupport;
 
 	u8 supportmax256vd;
-	u8 allow_fw_scan;
+	u8 pd_list_not_supported;
 	u16 fw_supported_vd_count;
 	u16 fw_supported_pd_count;
 

drivers/scsi/megaraid/megaraid_sas_base.c

@@ -1838,7 +1838,7 @@ static int megasas_slave_configure(struct scsi_device *sdev)
 	struct megasas_instance *instance;
 
 	instance = megasas_lookup_instance(sdev->host->host_no);
-	if (instance->allow_fw_scan) {
+	if (instance->pd_list_not_supported) {
 		if (sdev->channel < MEGASAS_MAX_PD_CHANNELS &&
 			sdev->type == TYPE_DISK) {
 			pd_index = (sdev->channel * MEGASAS_MAX_DEV_PER_CHANNEL) +
@@ -1874,7 +1874,8 @@ static int megasas_slave_alloc(struct scsi_device *sdev)
 		pd_index =
 			(sdev->channel * MEGASAS_MAX_DEV_PER_CHANNEL) +
 			sdev->id;
-		if ((instance->allow_fw_scan || instance->pd_list[pd_index].driveState ==
+		if ((instance->pd_list_not_supported ||
+			instance->pd_list[pd_index].driveState ==
 			MR_PD_STATE_SYSTEM)) {
 			goto scan_target;
 		}
@@ -4087,7 +4088,13 @@ megasas_get_pd_list(struct megasas_instance *instance)
 
 	switch (ret) {
 	case DCMD_FAILED:
-		megaraid_sas_kill_hba(instance);
+		dev_info(&instance->pdev->dev, "MR_DCMD_PD_LIST_QUERY "
+			"failed/not supported by firmware\n");
+
+		if (instance->ctrl_context)
+			megaraid_sas_kill_hba(instance);
+		else
+			instance->pd_list_not_supported = 1;
 		break;
 	case DCMD_TIMEOUT:
 
@@ -5034,7 +5041,6 @@ static int megasas_init_fw(struct megasas_instance *instance)
 	case PCI_DEVICE_ID_DELL_PERC5:
 	default:
 		instance->instancet = &megasas_instance_template_xscale;
-		instance->allow_fw_scan = 1;
 		break;
 	}