[PATCH 10/13] scsi: arcmsr: fix clear doorbell queue on ACB_ADAPTER_TYPE_B controller

[Ching Huang]

From: Ching Huang <ching2...@areca.com.tw>

fix clear doorbell queue on ACB_ADAPTER_TYPE_B controller

Signed-off-by: Ching Huang <ching2...@areca.com.tw>
---

diff -uprN a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
--- a/drivers/scsi/arcmsr/arcmsr_hba.c  2017-11-08 18:54:18.000000000 +0800
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c  2017-11-08 18:54:58.000000000 +0800
@@ -4202,10 +4202,19 @@ static void arcmsr_clear_doorbell_queue_
 
        case ACB_ADAPTER_TYPE_B: {
                struct MessageUnit_B *reg = acb->pmuB;
-               /*clear interrupt and message state*/
-               writel(ARCMSR_MESSAGE_INT_CLEAR_PATTERN, reg->iop2drv_doorbell);
+               uint32_t outbound_doorbell, i;
+               writel(ARCMSR_DOORBELL_INT_CLEAR_PATTERN, 
reg->iop2drv_doorbell);
                writel(ARCMSR_DRV2IOP_DATA_READ_OK, reg->drv2iop_doorbell);
                /* let IOP know data has been read */
+               for(i=0; i < 200; i++) {
+                       msleep(20);
+                       outbound_doorbell = readl(reg->iop2drv_doorbell);
+                       if( outbound_doorbell & ARCMSR_IOP2DRV_DATA_WRITE_OK) {
+                               writel(ARCMSR_DOORBELL_INT_CLEAR_PATTERN, 
reg->iop2drv_doorbell);
+                               writel(ARCMSR_DRV2IOP_DATA_READ_OK, 
reg->drv2iop_doorbell);
+                       } else
+                               break;
+               }
                }
                break;
        case ACB_ADAPTER_TYPE_C: {