scsi: arcmsr: Add an option of set dma_mask_64 for ACB_ADAPTER_TYPE_A

From Ching Huang <ching2048@areca.com.tw>

Add an option of set dma_mask_64 for ACB_ADAPTER_TYPE_A
Signed-off-by: Ching Huang <ching2048@areca.com.tw>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/arcmsr/arcmsr_hba.c

@@ -91,6 +91,10 @@ static int cmd_per_lun = ARCMSR_DEFAULT_CMD_PERLUN;
 module_param(cmd_per_lun, int, S_IRUGO);
 MODULE_PARM_DESC(cmd_per_lun, " device queue depth(1 ~ 128), default is 32");
 
+static int dma_mask_64 = 0;
+module_param(dma_mask_64, int, S_IRUGO);
+MODULE_PARM_DESC(dma_mask_64, " set DMA mask to 64 bits(0 ~ 1), dma_mask_64=1(64 bits), =0(32 bits)");
+
 static int set_date_time = 0;
 module_param(set_date_time, int, S_IRUGO);
 MODULE_PARM_DESC(set_date_time, " send date, time to iop(0 ~ 1), set_date_time=1(enable), default(=0) is disable");