[PATCH 1/2] scsi: arcmsr: fix doorbell status may arrived late on ARC-1886

[ching Huang]

From: ching Huang <ching2048@xxxxxxxxxxxx>

This patch fix the doorbell status coming from IOP may late.
The doorbell status value should not be 0.

Signed-off-by: ching Huang <ching2048@xxxxxxxxxxxx>
---

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 930972c..98e3d57 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -2419,10 +2419,18 @@ static void arcmsr_hbaD_doorbell_isr(struct AdapterControlBlock *pACB)
 
 static void arcmsr_hbaE_doorbell_isr(struct AdapterControlBlock *pACB)
 {
-	uint32_t outbound_doorbell, in_doorbell, tmp;
+	uint32_t outbound_doorbell, in_doorbell, tmp, i;
 	struct MessageUnit_E __iomem *reg = pACB->pmuE;
 
-	in_doorbell = readl(&reg->iobound_doorbell);
+	if (pACB->adapter_type == ACB_ADAPTER_TYPE_F) {
+		for (i = 0; i < 5; i++) {
+			in_doorbell = readl(&reg->iobound_doorbell);
+			if (in_doorbell != 0)
+				break;
+		}
+	}
+	else
+		in_doorbell = readl(&reg->iobound_doorbell);
 	outbound_doorbell = in_doorbell ^ pACB->in_doorbell;
 	do {
 		writel(0, &reg->host_int_status); /* clear interrupt */