DMA Problem With DVD Drive

[Gerard Seibert]

Wednesday, January 28, 2004 8:54:32 AM

Try entering the following into your /boot/loader.conf file:

hw.ata.ata_dma=1
hw.ata.atapi_dma=1
hw.ata.wc=1

That solved the problem for me. Of course you will have to reboot after entering the commands.

Gerard Seibert
gerard-seibert at rcn.com

********** Reply Separator **********

On Tuesday, January 27, 2004 12:59:23 AM freebsd-questions-request at freebsd.org wrote:

Date: Fri, 16 Jan 2004 09:34:22 +0100 (CET)
From: "Roman Kennke" <roman at interview-machine.com>
Subject: DMA problem with DVD drive
To: <freebsd-questions at freebsd.org>
Message-ID:
	<49184.217.187.89.107.1074242062.squirrel at interview-machine.com>
Content-Type: text/plain; charset=iso-8859-1


Hi there,

I am not able to enable DMA for my DVD drive. When I issue 'atacontrol
mode 1 UDMA100 XXX' and access the drive, first the drive access hangs,
and after a view seconds the machine locks up completely. This also hold
true for all other DMA modes.
I am running FreeBSD 5.2 on a Fujitsu-Siemens Amilo A Notebook. I would
send more info about the ATA/IDE controller, and the error messages but I
don't know, how to get to this info.
BTW: I know that DMA works for this drive. I have got it working at least
with linux 2.4.22, althought I also had alot of DMA problems with other
versions, so I suspect the hardware (controller) is flakey.
Any help is appreciated. Here follows some output from dmesg:

moonlight# dmesg | grep ata
atapci0: <AcerLabs Aladdin UDMA100 controller> port 0xa000-0xa00f at
device 4.0 on pci0ata0: at 0x1f0 irq 14 on atapci0
ata0: [MPSAFE]
ata1: at 0x170 irq 15 on atapci0
ata1: [MPSAFE]
ad0: 28615MB <FUJITSU MHR2030AT> [58140/16/63] at ata0-master UDMA100
acd0: CDRW <TOSHIBA DVD-ROM SD-R2212> at ata1-master PIO4



Ciao, Roman