VectorLinux

The nuts and bolts => Software General => Topic started by: retired1af on June 16, 2007, 04:45:52 pm

Title: DMA and Xine
Post by: retired1af on June 16, 2007, 04:45:52 pm
Tossed a DVD into the player this evening and the play was extremely choppy. So I bugged out to toss this command in and received:

root:# hdparm -d1 /dev/dvd

/dev/dvd:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 using_dma    =  0 (off)

As I understand it, to get this to work involves a recompile of the kernel. First question is, how and what do I use to get DMA to work, and second, why isn't DMA included as default?
Title: Re: DMA and Xine
Post by: Joe1962 on June 16, 2007, 05:43:42 pm
As I understand it, to get this to work involves a recompile of the kernel.
Probably not.

First question is, how and what do I use to get DMA to work...
I was given 2 links about this, but haven't tried yet:
http://thomer.com/howtos/dma_on_sata_dvd.html
http://www.thinkwiki.org/wiki/Problems_with_SATA_and_Linux#No_DMA_on_DVD_drive

...and second, why isn't DMA included as default?
This seems to be something the sata driver devs need to address.
Title: Re: DMA and Xine
Post by: bigpaws on June 17, 2007, 02:37:12 pm
Try this as root:

echo 1024 >  /proc/sys/dev/rtc/max-user-freq

That should fix it and add it to /etc/rc.d/rc.local.

HTH

Bigpaws
Title: Re: DMA and Xine
Post by: retired1af on June 17, 2007, 02:47:25 pm
Bigpaws, what should that add? I didn't see anything in the file after executing the echo command.
Title: Re: DMA and Xine
Post by: bigpaws on June 17, 2007, 04:30:39 pm
Now try xine. It sets the size of rtc.

Bigpaws
Title: Re: DMA and Xine
Post by: retired1af on June 18, 2007, 04:59:45 am
Still choppy and jerky... Not much change at all.  Funny thing is, MPlayer works fairly well to where the dvd is watchable.
Title: Re: DMA and Xine
Post by: nightflier on June 18, 2007, 05:11:24 am
Can you change BIOS settings for the controller to "legacy mode" or similar?
Title: Re: DMA and Xine
Post by: retired1af on June 18, 2007, 05:45:50 am
Not really.. BIOS is set to detect all devices.