scsi: pm80xx: Remove global lock from outbound queue processing

Introduce spin lock for outbound queue. With this, driver need not acquire
HBA global lock for outbound queue processing.

Link: https://lore.kernel.org/r/20210415103352.3580-9-Viswas.G@microchip.com
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Viswas G <Viswas.G@microchip.com>
Signed-off-by: Ruksar Devadi <Ruksar.devadi@microchip.com>
Signed-off-by: Ashokkumar N <Ashokkumar.N@microchip.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/pm8001/pm8001_init.c

@@ -267,7 +267,8 @@ static int pm8001_alloc(struct pm8001_hba_info *pm8001_ha,
 {
 	int i, count = 0, rc = 0;
 	u32 ci_offset, ib_offset, ob_offset, pi_offset;
-	struct inbound_queue_table *circularQ;
+	struct inbound_queue_table *ibq;
+	struct outbound_queue_table *obq;
 
 	spin_lock_init(&pm8001_ha->lock);
 	spin_lock_init(&pm8001_ha->bitmap_lock);
@@ -315,8 +316,8 @@ static int pm8001_alloc(struct pm8001_hba_info *pm8001_ha,
 	pm8001_ha->memoryMap.region[IOP].alignment = 32;
 
 	for (i = 0; i < count; i++) {
-		circularQ = &pm8001_ha->inbnd_q_tbl[i];
-		spin_lock_init(&circularQ->iq_lock);
+		ibq = &pm8001_ha->inbnd_q_tbl[i];
+		spin_lock_init(&ibq->iq_lock);
 		/* MPI Memory region 3 for consumer Index of inbound queues */
 		pm8001_ha->memoryMap.region[ci_offset+i].num_elements = 1;
 		pm8001_ha->memoryMap.region[ci_offset+i].element_size = 4;
@@ -345,6 +346,8 @@ static int pm8001_alloc(struct pm8001_hba_info *pm8001_ha,
 	}
 
 	for (i = 0; i < count; i++) {
+		obq = &pm8001_ha->outbnd_q_tbl[i];
+		spin_lock_init(&obq->oq_lock);
 		/* MPI Memory region 4 for producer Index of outbound queues */
 		pm8001_ha->memoryMap.region[pi_offset+i].num_elements = 1;
 		pm8001_ha->memoryMap.region[pi_offset+i].element_size = 4;

drivers/scsi/pm8001/pm8001_sas.h

@@ -456,6 +456,7 @@ struct outbound_queue_table {
 	u32			dinterrup_to_pci_offset;
 	__le32			producer_index;
 	u32			consumer_idx;
+	spinlock_t		oq_lock;
 };
 struct pm8001_hba_memspace {
 	void __iomem  		*memvirtaddr;

drivers/scsi/pm8001/pm80xx_hwi.c

@@ -4133,8 +4133,8 @@ static int process_oq(struct pm8001_hba_info *pm8001_ha, u8 vec)
 			return ret;
 		}
 	}
-	spin_lock_irqsave(&pm8001_ha->lock, flags);
 	circularQ = &pm8001_ha->outbnd_q_tbl[vec];
+	spin_lock_irqsave(&circularQ->oq_lock, flags);
 	do {
 		/* spurious interrupt during setup if kexec-ing and
 		 * driver doing a doorbell access w/ the pre-kexec oq
@@ -4160,7 +4160,7 @@ static int process_oq(struct pm8001_hba_info *pm8001_ha, u8 vec)
 				break;
 		}
 	} while (1);
-	spin_unlock_irqrestore(&pm8001_ha->lock, flags);
+	spin_unlock_irqrestore(&circularQ->oq_lock, flags);
 	return ret;
 }