Re: Permissions denied when enabling DMA

[Alvin Oga <aoga@ns.Linux-Consulting.com>]

hi wayn

you need to make sure the the ide chipset
swupported by the kernel you're using

- look at the motherboard, figure out what chipset
  and than check your kernel config options

- try installing that module for the chipset

c ya
alvin


On Fri, 1 Aug 2003, Wayne Gemmell wrote:

> Hi, I'm running the bf24 kernel and trying to enable DMA on my hard drive.
> My first question is, is DMA already activated?
> 
> running hdparm /dev/hdc yields
> 	 using_dma    =  0 (off)
> while running hdparm -i /dev/hdc yields
> 	DMA modes: mdma0 mdma1 mdma2 udma0 udma1 udma2
> and hdparm -I /dev/hdc outputs
> 	DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5
>              Cycle time: min=120ns recommended=120ns
> Could somebody please help me make sence of these readings?
> 
> Now when I run hdparm -d1 /dev/hdc I get 
> 	
> 	 Wuler:/var/www/Digi-CRAUDphp/Venue# hdparm -d1 /dev/hdc
> 		/dev/hdc:
>  		setting using_dma to 1 (on)
>  		HDIO_SET_DMA failed: Operation not permitted
>  		using_dma    =  0 (off)
>