Problems turning on the DMA on AMD chipset

kushalkoolwal · 06-14-2006, 05:27 PM

I am using Debian etch(kernel 2.6.16) and I am trying to get the DMA enabled for my harddrives.

Now I know from my hardware vendor that to get the DMA support I have to enable the support for "AMD and Nvidia chipset"(amd7xx) option in the kernel configuration which I already did.

Now when I do a hdparm /dev/hda I get this

Code:

/dev/hda:
 multcount    = 16 (on)
 IO_support   =  1 (32-bit)
 unmaskirq    =  1 (on)
 using_dma    =  0 (off)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 geometry     = 8355/16/63, sectors = 8421840, start = 0

Clearly the DMA looks off.

Now when I do hdparm -i /dev/hda I get this

Code:

/dev/hda:

 Model=WDC WD43AA, FwRev=29.05T29, SerialNo=WD-WM9020138788
 Config={ HardSect NotMFM HdSw>15uSec SpinMotCtl Fixed DTR>5Mbs FmtGapReq }
 RawCHS=8355/16/63, TrkSize=57600, SectSize=600, ECCbytes=40
 BuffType=DualPortCache, BuffSize=2048kB, MaxMultSect=16, MultSect=16
 CurCHS=8355/16/63, CurSects=8421840, LBA=yes, LBAsects=8421840
 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
 PIO modes:  pio0 pio1 pio2 pio3 pio4 
 DMA modes:  mdma0 mdma1 mdma2 
 UDMA modes: udma0 udma1 *udma2 
 AdvancedPM=no WriteCache=enabled
 Drive conforms to: Unspecified:  ATA/ATAPI-1 ATA/ATAPI-2 ATA/ATAPI-3 ATA/ATAPI-4

 * signifies the current active mode

Now if you look at the above output it seems that I have DMA enabled, but then when why in the first ouput it showed "using_dma = 0 (off)" ??

Also when I try to explicity enable the DMA by the following command, I get this
hdparm -d1 /dev/hda

Code:

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

Now on searching I have found that if someone gets a message like above then it means that DMA is not enabled. So the confusion to me right now is why does the hdparm -i /dev/hda shows that I am using DMA modes.

Can anyone clear the confusion, if at this point I have DMA enabled or not? Is there any other utility which can confirm this?

Btw, here is the output of my lspci

Code:

0000:00:01.0 Host bridge: National Semiconductor Corporation Geode GX2 Host Bridge (rev 21)
0000:00:01.1 VGA compatible controller: National Semiconductor Corporation Geode GX2 Graphics Processor
0000:00:0e.0 Ethernet controller: Intel Corporation 8255xER/82551IT Fast Ethernet Controller (rev 10)
0000:00:0f.0 ISA bridge: Advanced Micro Devices [AMD] CS5536 [Geode companion] ISA (rev 02)
0000:00:0f.2 IDE interface: Advanced Micro Devices [AMD]: Unknown device 2092 (rev 01)
0000:00:0f.3 Multimedia audio controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] Audio (rev 01)
0000:00:0f.4 USB Controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] OHC (rev 02)
0000:00:0f.5 USB Controller: Advanced Micro Devices [AMD] CS5536 [Geode companion] EHC (rev 02)

Any help will be really appreciated?

Thanks in advance.

osor · 06-14-2006, 06:18 PM

What does it say in /proc/dma or /proc/diskstats

kushalkoolwal · 06-14-2006, 06:48 PM

Quote:

Originally Posted by osor

What does it say in /proc/dma or /proc/diskstats

Thanks for reply dude, here are the outputs:

/proc/dma

Code:

4: cascade

/proc/diskstats

Code:

   1    0 ram0 0 0 0 0 0 0 0 0 0 0 0
   1    1 ram1 0 0 0 0 0 0 0 0 0 0 0
   1    2 ram2 0 0 0 0 0 0 0 0 0 0 0
   1    3 ram3 0 0 0 0 0 0 0 0 0 0 0
   1    4 ram4 0 0 0 0 0 0 0 0 0 0 0
   1    5 ram5 0 0 0 0 0 0 0 0 0 0 0
   1    6 ram6 0 0 0 0 0 0 0 0 0 0 0
   1    7 ram7 0 0 0 0 0 0 0 0 0 0 0
   1    8 ram8 0 0 0 0 0 0 0 0 0 0 0
   1    9 ram9 0 0 0 0 0 0 0 0 0 0 0
   1   10 ram10 0 0 0 0 0 0 0 0 0 0 0
   1   11 ram11 0 0 0 0 0 0 0 0 0 0 0
   1   12 ram12 0 0 0 0 0 0 0 0 0 0 0
   1   13 ram13 0 0 0 0 0 0 0 0 0 0 0
   1   14 ram14 0 0 0 0 0 0 0 0 0 0 0
   1   15 ram15 0 0 0 0 0 0 0 0 0 0 0
   3    0 hda 6769 22235 247570 78960 146 428 4592 1760 0 74436 80716
   3    1 hda1 28979 247370 574 4592
   3   64 hdb 0 0 0 0 0 0 0 0 0 0 0

kushalkoolwal · 06-19-2006, 05:09 PM

Still no one????

justanothersteve · 06-19-2006, 05:26 PM

I had this problem a whiiiiiiile back, I believe mine was linked to the kernel. Check that you have the appropriate drivers compiled into your kernel for your drive and/or board's chipset.

kushalkoolwal · 06-19-2006, 07:29 PM

Quote:

Originally Posted by justanothersteve

I had this problem a whiiiiiiile back, I believe mine was linked to the kernel. Check that you have the appropriate drivers compiled into your kernel for your drive and/or board's chipset.

I have been stuck on this problem now for more than a week. I have double verified my kernel config and I have compiled the right drivers for my chipset i.e.amd74xx. Still I can't get it to work.

COuld this be a BIOS/Hardware problem rather than kernel problem?

Thanks