Subject: Re: PCI-audio & endianness (eso.c/mulaw.c)
To: Eduardo E. Horvath <firstname.lastname@example.org>
From: Jason Thorpe <email@example.com>
Date: 10/27/1999 10:45:54
On Wed, 27 Oct 1999 09:17:31 -0700 (PDT)
firstname.lastname@example.org (Eduardo E. Horvath) wrote:
> > I guess most PCI bus-master devices assume the host is little endian,
> > so bswap*() functions are needed on passing non-bytestream data via DMA.
> > (i.e. on accessing variables allocated by bus_dmamem_alloc(9) and
> > bus_dmamem_map(9))
> Once again this should be handled by bus_space(9) macros. We may need
> to add some new ones specifically for the host to access DMA memory,
> if it's only being mapped in once and used statically as an area for
> host/device communication.
Since it's obviously not "bus space", random memory being DMA'd to a
device can't be handled with bus_space(9).
-- Jason R. Thorpe <email@example.com>