hardware bug whereby when the BIOS is enabled, transfers to/from
           the same address range the BIOS occupies modulo 16MB are handled
           incorrectly.  Only properly functioning BT-445S Host Adapters
-          have firmware version 3.37, so require that ISA Bounce Buffers
-          be used for the buggy BT-445S models if there is more than 16MB
-          memory.
+          have firmware version 3.37.
         */
-       if (adapter->bios_addr > 0 && strcmp(adapter->model, "BT-445S") == 0 &&
-                       strcmp(adapter->fw_ver, "3.37") < 0 &&
-                       (void *) high_memory > (void *) MAX_DMA_ADDRESS)
-               adapter->need_bouncebuf = true;
+       if (adapter->bios_addr > 0 &&
+           strcmp(adapter->model, "BT-445S") == 0 &&
+           strcmp(adapter->fw_ver, "3.37") < 0)
+               return blogic_failure(adapter, "Too old firmware");
        /*
           Initialize parameters common to MultiMaster and FlashPoint
           Host Adapters.
                if (adapter->drvr_opts != NULL &&
                                adapter->drvr_opts->qdepth[tgt_id] > 0)
                        qdepth = adapter->drvr_opts->qdepth[tgt_id];
-               else if (adapter->need_bouncebuf)
-                       qdepth = BLOGIC_TAG_DEPTH_BB;
                adapter->qdepth[tgt_id] = qdepth;
        }
-       if (adapter->need_bouncebuf)
-               adapter->untag_qdepth = BLOGIC_UNTAG_DEPTH_BB;
-       else
-               adapter->untag_qdepth = BLOGIC_UNTAG_DEPTH;
+       adapter->untag_qdepth = BLOGIC_UNTAG_DEPTH;
        if (adapter->drvr_opts != NULL)
                adapter->common_qdepth = adapter->drvr_opts->common_qdepth;
        if (adapter->common_qdepth > 0 &&
        host->this_id = adapter->scsi_id;
        host->can_queue = adapter->drvr_qdepth;
        host->sg_tablesize = adapter->drvr_sglimit;
-       host->unchecked_isa_dma = adapter->need_bouncebuf;
        host->cmd_per_lun = adapter->untag_qdepth;
 }
 
 #if 0
        .eh_abort_handler = blogic_abort,
 #endif
-       .unchecked_isa_dma = 1,
        .max_sectors = 128,
 };