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VIAIDE(4) NetBSD Kernel Interfaces Manual VIAIDE(4)
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viaide -- AMD, NVIDIA and VIA IDE disk controllers driver
viaide* at pci? dev ? function ? flags 0x0000
The viaide driver supports the following IDE controllers and provides the
interface with the hardware for the ata driver:
- Advanced Micro Devices AMD-756, 766, 768 and CS5536 IDE Con-
- NVIDIA nForce, nForce2, nForce2 400, nForce3, nForce3 250,
nForce4, MCP04, MCP55, MCP61, MCP65, MCP67 IDE and SATA Con-
- VIA Technologies VT82C586, VT82C586A, VT82C596A, VT82C686A,
VT8233A, VT8235, VT8237/VT8237R IDE Controllers, VT6421 Serial
RAID Controller and CX700 IDE Controller.
The 0x0002 flag forces the viaide driver to disable DMA on chipsets for
which DMA would normally be enabled. This can be used as a debugging
aid, or to work around problems where the IDE controller is wired up to
the system incorrectly.
ata(4), atapi(4), intro(4), pci(4), pciide(4), wd(4), wdc(4)
Drives on the VT6421 Serial RAID Controller can only be accessed after
they have been configured into RAID or JBOD sets via its BIOS. It is
also inaptly named as it has both SATA and PATA interfaces.
The AMD756 chip revision D2 has a bug affecting DMA (but not Ultra-DMA)
modes. The workaround documented by AMD is to not use DMA on any drive
which does not support Ultra-DMA modes. This does not appear to be nec-
essary on all drives, the PCIIDE_AMD756_ENABLEDMA option can be used to
force multiword DMA on the buggy revisions. Multiword DMA can eventually
be disabled on a per-drive basis with config flags, see wd(4). The bug,
if triggered, will cause a total system hang.
The timings used for the PIO and DMA modes for controllers listed above
are for a PCI bus running at 30 or 33 MHz. This driver may not work
properly on overclocked systems.
NetBSD 10.99 August 31, 2007 NetBSD 10.99