NAME
iopaau
- Intel I/O Processor Application Accelerator Unit
SYNOPSIS
iopxs* at mainbus?
iopaau* at iopxs?
DESCRIPTION
The Application Accelerator Unit, or AAU, provides hardware-assisted
support for performing block fills on a region of memory, XOR of
multiple regions of memory
(parity computation),
and parity verification.
The
iopaau
driver supports the Application Accelerator Units on the following
Intel I/O Processors:
-
Intel i80321 I/O Processor
The
iopaau
driver provides a back-end to the
dmover(9)
interface, and supports the following
dmover(9)
functions:
- zero
-
Zero a region of memory
- fill8
-
Fill a region of memory with an 8-bit value
- copy
-
Copy a region of memory
- xor2
-
Perform an XOR of 2 input streams
- xor3
-
Perform an XOR of 3 input streams
- xor4
-
Perform an XOR of 4 input streams
- xor5
-
Perform an XOR of 5 input streams
- xor6
-
Perform an XOR of 6 input streams
- xor7
-
Perform an XOR of 7 input streams
- xor8
-
Perform an XOR of 8 input streams
SEE ALSO
dmover(9)
HISTORY
The
iopaau
device first appeared in
NetBSD2.0.
AUTHORS
The
iopaau
driver was written by
Jason R. Thorpe <thorpej@wasabisystems.com>
and contributed by Wasabi Systems, Inc.
BUGS
Due to limitations in how scatter-gather is done by the AAU hardware,
a given DMA segment must be the same length for the output stream and
each input stream. The easiest way to achieve this is to ensure that
all streams used in an AAU operation begin at the same offset into a
page.