Re: Can we remove the Zone_DMA?

From: Oliver Neukum
Date: Sun Apr 04 2010 - 03:31:11 EST


Am Sonntag, 4. April 2010 06:21:54 schrieb tek-life:
> In Linux , The Memory is divided to three zone. They are ZONE_DMA
> 、ZONE_NORMAL and ZONE_HIGHMEM. From the book of "Undstand the Linux
> kernel ", the ZONE_DMA has the effect that the Direct Memory Access
> (DMA) processors for old ISA buses have a strong limitation: they are
> able to address only the first 16 MB of RAM. SO ,we must set a zone
> for the DMA on ISA bus. And I suspect that the hardware has
> developed so quickly .And in this days the ISA has been weeded out.

Floppy disks & paralell ports still use DMA

Regards
Oliver
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