>The PCI/ISA chipset on the ASUS board that I have supports better DMA
>for ISA devices, so that you can DMA anywhere in the address space,
>even from or to an ISA device.  I think this is a pretty common

How is this possible with only 24 address lines?  Does the ASUS board
also put extra address lines on the ISA socket?  Which add-in boards
would support this?

>chipset, and there may be similar functionality available in some
>modern EISA chipset - maybe support for this stuff should be
>considered along with bounce buffers?

Any fully-functional EISA chipset automagically works in 32-bit
addressing per EISA spec.  EISA DMA isn't ISA DMA.  If EISA doesn't
work this way, it's broken.

-----------------------------------------------------------------------------
  Michael L. VanLoon                                 michaelv@HeadCandy.com
       --<  Free your mind and your machine -- NetBSD free un*x  >--
     NetBSD working ports: 386+PC, Mac, Amiga, HP300, Sun3, Sun4, PC532,
                           DEC pmax (MIPS R2k/3k), DEC/AXP (Alpha)
     NetBSD ports in progress: VAX and others...
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