ALi M1543 on P200

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I cannot use DMA on my new disks. UDMA is enabled in BIOS in mode UDMA 2. It
doesn't work even in auto mode. ide0=dma doesn't work either. hdparm -d 1
/dev/hda causes "operation not permitted"

/dev/hda:

 Model=ST320413A, FwRev=3.39, SerialNo=7ED1R0TR
 Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs RotSpdTol>.5% }
 RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=0
 BuffType=unknown, BuffSize=512kB, MaxMultSect=16, MultSect=16
 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=39102336
 IORDY=on/off, tPIO={min:240,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 udma3 udma4 udma5
 AdvancedPM=no WriteCache=enabled
 Drive conforms to: device does not report version:  1 2 3 4 5

ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
ALI15X3: IDE controller at PCI slot 00:0b.0
PCI: Assigned IRQ 10 for device 00:0b.0
ALI15X3: chipset revision 32
ALI15X3: not 100% native mode: will probe irqs later
ALI15X3: simplex device with no drives: DMA disabled
ide0: ALI15X3 Bus-Master DMA disabled (BIOS)
ALI15X3: simplex device with no drives: DMA disabled
ide1: ALI15X3 Bus-Master DMA disabled (BIOS)
hda: ST320413A, ATA DISK drive
hdb: WDC WD300BB-00AUA1, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
hda: host protected area => 1
hda: 39102336 sectors (20020 MB) w/512KiB Cache, CHS=2434/255/63
hdb: host protected area => 1
hdb: 58633344 sectors (30020 MB) w/2048KiB Cache, CHS=3649/255/63