I needed to do exactly the same thing on my machine. Understanding english does not mean I knew how to
enable the chipset module for your motherboard in the Kernel configuration.
So I googled the web to figure out, how to do it. And this is how:
run the 'lspci -v' command, from the output try to find the name/vendor of the IDE interface chip:
00:0f.0 IDE interface: VIA Technologies, Inc. VT82C586A/B/VT82C686/A/B/VT8233/A/C/VT8235 PIPC Bus Master IDE (rev 06) (prog-if 8a [Master SecP PriP])
Subsystem: Elitegroup Computer Systems: Unknown device 1b41
Flags: bus master, medium devsel, latency 32
I/O ports at dc00 [size=16]
Capabilities: [c0] Power Management version 2
The chip that controls access to the IDE bus on my motherboard is the: "VIA VT82Cxxxx".
Armed with this knowledge you can 'enable the chipset module for your motherboard in the Kernel configuration' and build a new kernel:
If you're using 'make xconfig' to configure your kernel the find the "ATA/IDE/MFM/RLL support" menu/button. From there click on the "IDE, ATA and ATAPI Block devices" button. Under the "PCI IDE chipset support" section they list a bunch of Chipset support options, I found mine "VIA82CXXX chipset support" and selected to build it in the kernel - not as a module (as suggested by other forums).
Then cross your fingers, tap the heels of your shoes together and compile, install the kernel and reboot.
After the reboot try to enable hard disk DMA with hdparm again.
hope it helps.