Copyright (c) 1998 Jason R. Thorpe.
All rights reserved.
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3. All advertising materials mentioning features or use of this software
must display the following acknowledgements:
This product includes software developed for the NetBSD Project
by Jason R. Thorpe.
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.lp .nr PS 14
.b A Machine-Independent DMA Framework for NetBSD .r .nr PS 12
.r
.r Jason R. Thorpe\**
.i Numerical Aerospace Simulation Facility
NASA Ames Research Center
.r
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.nr PS 12
.b Abstract
.nr PS 10
.pp
One of the challenges in implementing a portable kernel is finding
good abstractions for semantically-similar operations which often have
very machine-dependent implementations. This is especially important
on modern machines which share common architectural features, e.g.
the PCI bus.
.pp
This paper describes why a machine-independent DMA mapping abstraction
is needed, the design considerations for such an abstraction, and the
implementation of this abstraction in the NetBSD/alpha and
NetBSD/i386 kernels.
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\**Jason R. Thorpe is an employee of MRJ Technology Solutions, Inc.
This work is funded by NASA contract NAS2-14303.
.)f