I wrote:

> Maybe all you have to do to support ncr53c90 MCA SCSI is
> to implement glue functions including DMA stuff.
> (like dev/pci/pcscp.c)

Ah, I notice you've already committed mca_esp.c after I posted this.

NCR53c9x chips (except AM53c974) do not have DMA engine in it,
so MCA SCSI would have some other stuff for DMA.
You might have to search another doc.

If you will start to support PIO-only transfers,
dev/pcmcia/esp_pcmcia.c or arch/mac68k/obio/esp.c has
pseudo-DMA functions for PIO and they might help.
(That's what I did on Am53c974 support)
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp