# tried my best.. can't get AMD760 dma for LG GSA-4040b dvd-rw

## mtv not bullets

I'm having a hell of a time playing back dvds.

hah

I can't seem to get DMA to enable on ide0 for my LG 4x dvd+-rw drive.

Keep in mind I don't have anything on the onboard 760 controllers, hard drives are on promise raid.

I do have kernel support for the AMD IDE, not as module.

I have tried all the obvious things like "hdparm -d1 /dev/hda"

I think I have used the current setup under windows before with no problem, but it might have been in another machine.

Any help is most appreciated, I am not experienced enough to diagnose this problem.

End of dmesg:

```

ide0: Speed warnings UDMA 3/4/5 is not functional.

hda: CHECK for good STATUS

```

hdparm -I /dev/hda

```

/dev/hda:

 

ATAPI CD-ROM, with removable media

        Model Number:       HL-DT-ST DVDRAM GSA-4040B

        Serial Number:      K1B3A8E5822

        Firmware Revision:  A302

Standards:

        Likely used CD-ROM ATAPI-1

Configuration:

        DRQ response: 50us.

        Packet size: 12 bytes

Capabilities:

        LBA, IORDY(can be disabled)

        DMA: mdma0 mdma1 mdma2 udma0 *udma1 udma2

             Cycle time: min=120ns recommended=120ns

        PIO: pio0 pio1 pio2 pio3 pio4

             Cycle time: no flow control=120ns  IORDY flow control=120ns

HW reset results:

        CBLID- above Vih

        Device num = 0

```

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## NeddySeagoon

mtv not bullets,

You posted  *Quote:*   

> Capabilities:
> 
>         LBA, IORDY(can be disabled)
> 
>         DMA: mdma0 mdma1 mdma2 udma0 *udma1 udma2 

 which shows that you are using udma1, which is a DMA mode. You should be able to play DVDs like that. To get udma2 you need an 80 conductor IDE cable. If you already have one, it may not be getting detected. I would guess that getting the data off the DVD is not your problem.

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## mtv not bullets

I probably should have also posted this too..

Its set to udma1 but does not have dma enabled..?

```

root@fux0r mike # hdparm -d1 /dev/hda

 

/dev/hda:

 setting using_dma to 1 (on)

 HDIO_SET_DMA failed: Operation not permitted

 using_dma    =  0 (off)

root@fux0r mike #

```

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## NeddySeagoon

mtv not bullets,

That means that the kernel does not know how to control your IDE chip set to set DMA.

You need to reconfigure and build your kernel. The following is for a 2.6.6 kernel but others are similar. Navigate to

```
Device Drivers

 ->ATA/ATAPI/MFM/RLL support

    Choose the following as built in (not modules)

      Enhanced IDE/MFM/RLL disk/cdrom/tape/floppy support

      Include IDE/ATA-2 DISK support

      Include IDE/ATAPI CDROM support

      generic/default IDE chipset support

      PCI IDE chipset support - On this submenu Choose

         Generic PCI IDE Chipset Support

         Generic PCI bus-master DMA support 

         Use PCI DMA by default when available

         Choose your chipset from the following list.
```

Add in anything else you feel the need for. This should get you DMA by default and the ability to contol it.

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## mtv not bullets

Ahhh. I shouldn't have needed any help figuring this out.   :Wink: 

If I knew or guessed my AMD760 motherboard had a VIA ide controller, I would have enabled VIA82Cxx from the get-go.

Thanks for your time. I really appreciate the quality and quantity of *free* help here.

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## moodboom

I can't believe it took me this long to figure this out, but I finally sat down and diagnosed my network throughput, disk throughput, etc.  I found that my server's harddrive speed was HORRIBLE.  Attempted to turn on DMA, failed, and ended up here.  I have the same VIA chipset.  A quick kernel adjustment, as suggested, and I'm all better now.  THANKS NeddySeagoon.  And thanks to the whole gentoo crew.  Rock on.

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