[PATCH 7/8] [SCSI] mpt2sas : Calulate the Reply post queue depth calculation as per the MPI spec

[PATCH 7/8] [SCSI] mpt2sas : Calulate the Reply post queue depth calculation as per the MPI spec

[Sreekanth Reddy]

Reply post queue depth calculation is not as per the MPI spec.

So, Modified the mpt2sas driver code to calculate the Reply post queue depth is as per
the MPI spec.

Signed-off-by: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
---
 
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index fc91a5a..47763b0 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -2487,23 +2487,25 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
 	/* reply free queue sizing - taking into account for 64 FW events */
 	ioc->reply_free_queue_depth = ioc->hba_queue_depth + 64;
 
+	/* calculate reply descriptor post queue depth */
+	ioc->reply_post_queue_depth = ioc->hba_queue_depth +
+					ioc->reply_free_queue_depth +  1 ;
 	/* align the reply post queue on the next 16 count boundary */
-	if (!ioc->reply_free_queue_depth % 16)
-		ioc->reply_post_queue_depth = ioc->reply_free_queue_depth + 16;
-	else
-		ioc->reply_post_queue_depth = ioc->reply_free_queue_depth +
-				32 - (ioc->reply_free_queue_depth % 16);
+	if (ioc->reply_post_queue_depth % 16)
+		ioc->reply_post_queue_depth += 16 - \
+			(ioc->reply_post_queue_depth % 16);
+
+
 	if (ioc->reply_post_queue_depth >
 	    facts->MaxReplyDescriptorPostQueueDepth) {
-		ioc->reply_post_queue_depth = min_t(u16,
-		    (facts->MaxReplyDescriptorPostQueueDepth -
-		    (facts->MaxReplyDescriptorPostQueueDepth % 16)),
-		    (ioc->hba_queue_depth - (ioc->hba_queue_depth % 16)));
-		ioc->reply_free_queue_depth = ioc->reply_post_queue_depth - 16;
-		ioc->hba_queue_depth = ioc->reply_free_queue_depth - 64;
+		ioc->reply_post_queue_depth =
+			facts->MaxReplyDescriptorPostQueueDepth -
+		    (facts->MaxReplyDescriptorPostQueueDepth % 16);
+		ioc->hba_queue_depth =
+			((ioc->reply_post_queue_depth - 64) / 2) - 1;
+		ioc->reply_free_queue_depth = ioc->hba_queue_depth + 64;
 	}
 
-
 	dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "scatter gather: "
 	    "sge_in_main_msg(%d), sge_per_chain(%d), sge_per_io(%d), "
 	    "chains_per_io(%d)\n", ioc->name, ioc->max_sges_in_main_message,