1.\" $NetBSD: viaide.4,v 1.10 2009/10/19 18:41:09 bouyer Exp $ 2.\" 3.\" Copyright (c) 2003 Manuel Bouyer. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22.\" INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24.\" 25.Dd August 31, 2007 26.Dt VIAIDE 4 27.Os 28.Sh NAME 29.Nm viaide 30.Nd AMD, NVIDIA and VIA IDE disk controllers driver 31.Sh SYNOPSIS 32.Cd "viaide* at pci? dev ? function ? flags 0x0000" 33.Cd "options PCIIDE_AMD756_ENABLEDMA" 34.Sh DESCRIPTION 35The 36.Nm 37driver supports the following IDE controllers 38and provides the interface with the hardware for the 39.Ic ata 40driver: 41.Bl -dash -compact -offset indent 42.It 43Advanced Micro Devices AMD-756, 766, 768 and CS5536 IDE Controllers 44.It 45NVIDIA nForce, nForce2, nForce2 400, nForce3, nForce3 250, 46nForce4, MCP04, MCP55, MCP61, MCP65, MCP67 IDE and SATA Controllers. 47.It 48VIA Technologies VT82C586, VT82C586A, VT82C596A, VT82C686A, VT8233A, 49VT8235, VT8237/VT8237R IDE Controllers, VT6421 Serial RAID Controller and 50CX700 IDE Controller. 51.El 52.Pp 53The 0x0002 flag forces the 54.Nm 55driver to disable DMA on chipsets for which DMA would normally be 56enabled. 57This can be used as a debugging aid, or to work around 58problems where the IDE controller is wired up to the system incorrectly. 59.Sh SEE ALSO 60.Xr ata 4 , 61.Xr atapi 4 , 62.Xr intro 4 , 63.Xr pci 4 , 64.Xr pciide 4 , 65.Xr wd 4 , 66.Xr wdc 4 67.Sh NOTES 68Drives on the VT6421 Serial RAID Controller can only be accessed 69after they have been configured into RAID or JBOD sets via its 70BIOS. 71It is also inaptly named as it has both SATA and PATA interfaces. 72.Sh BUGS 73The AMD756 chip revision D2 has a bug affecting DMA (but not Ultra-DMA) 74modes. 75The workaround documented by AMD is to not use DMA on any drive which 76does not support Ultra-DMA modes. 77This does not appear to be necessary on all drives, the 78PCIIDE_AMD756_ENABLEDMA option can be used to force multiword DMA 79on the buggy revisions. 80Multiword DMA can eventually be disabled on a 81per-drive basis with config flags, see 82.Xr wd 4 . 83The bug, if triggered, will cause a total system hang. 84.Pp 85The timings used for the PIO and DMA modes for controllers listed above 86are for a PCI bus running at 30 or 33 MHz. 87This driver may not work properly on overclocked systems. 88