megaraid_sas: MFI IO timeout handling

This patch will do proper error handling for DCMD timeout failure cases
for Fusion adapters:

1. For MFI adapters, in case of DCMD timeout (DCMD which must return
SUCCESS) driver will call kill adapter.

2. What action needs to be taken in case of DCMD timeout is decided by
function dcmd_timeout_ocr_possible().  DCMD timeout causing OCR is
applicable to the following commands:

	MR_DCMD_PD_LIST_QUERY
	MR_DCMD_LD_GET_LIST
	MR_DCMD_LD_LIST_QUERY
	MR_DCMD_CTRL_SET_CRASH_DUMP_PARAMS
	MR_DCMD_SYSTEM_PD_MAP_GET_INFO
	MR_DCMD_LD_MAP_GET_INFO

3. If DCMD fails from driver init path there are certain DCMDs which
must return SUCCESS. If those DCMDs fail, driver bails out. For optional
DCMDs like pd_info etc., driver continues without executing certain
functionality.

Signed-off-by: Sumit Saxena <sumit.saxena@avagotech.com>
Signed-off-by: Kashyap Desai <kashyap.desai@avagotech.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/megaraid/megaraid_sas.h

@@ -170,6 +170,7 @@
 
 /* Driver internal */
 #define DRV_DCMD_POLLED_MODE		0x1
+#define DRV_DCMD_SKIP_REFIRE		0x2
 
 /*
  * Definition for cmd_status
@@ -1093,6 +1094,11 @@ enum MR_SCSI_CMD_TYPE {
 	NON_READ_WRITE_SYSPDIO = 3,
 };
 
+enum DCMD_TIMEOUT_ACTION {
+	INITIATE_OCR = 0,
+	KILL_ADAPTER = 1,
+	IGNORE_TIMEOUT = 2,
+};
 /* Frame Type */
 #define IO_FRAME				0
 #define PTHRU_FRAME				1
@@ -1139,6 +1145,7 @@ enum MR_SCSI_CMD_TYPE {
 
 #define MFI_OB_INTR_STATUS_MASK			0x00000002
 #define MFI_POLL_TIMEOUT_SECS			60
+#define MFI_IO_TIMEOUT_SECS			180
 #define MEGASAS_SRIOV_HEARTBEAT_INTERVAL_VF	(5 * HZ)
 #define MEGASAS_OCR_SETTLE_TIME_VF		(1000 * 30)
 #define MEGASAS_ROUTINE_WAIT_TIME_VF		300
@@ -1918,7 +1925,7 @@ struct megasas_instance_template {
 	u32 (*init_adapter)(struct megasas_instance *);
 	u32 (*build_and_issue_cmd) (struct megasas_instance *,
 				    struct scsi_cmnd *);
-	void (*issue_dcmd) (struct megasas_instance *instance,
+	int (*issue_dcmd)(struct megasas_instance *instance,
 			    struct megasas_cmd *cmd);
 };
 
@@ -2016,6 +2023,19 @@ struct megasas_mgmt_info {
 	int max_index;
 };
 
+enum MEGASAS_OCR_CAUSE {
+	FW_FAULT_OCR			= 0,
+	SCSIIO_TIMEOUT_OCR		= 1,
+	MFI_IO_TIMEOUT_OCR		= 2,
+};
+
+enum DCMD_RETURN_STATUS {
+	DCMD_SUCCESS		= 0,
+	DCMD_TIMEOUT		= 1,
+	DCMD_FAILED		= 2,
+	DCMD_NOT_FIRED		= 3,
+};
+
 u8
 MR_BuildRaidContext(struct megasas_instance *instance,
 		    struct IO_REQUEST_INFO *io_info,