IOPAAU(4) | Device Drivers Manual (evbarm) | IOPAAU(4) |
iopaau
— Intel I/O
Processor Application Accelerator Unit
iopxs* at mainbus?
iopaau* at iopxs?
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:
The iopaau
driver provides a back-end to
the dmover(9) interface,
and supports the following
dmover(9) functions:
The iopaau
device first appeared in
NetBSD 2.0.
The iopaau
driver was written by
Jason R. Thorpe
<thorpej@wasabisystems.com>
and contributed by Wasabi Systems, Inc.
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.
August 2, 2002 | NetBSD 10.99 |