ALi PCI Chipset Integrated PATA Ports
This driver provides the support for the ALi/ULi PCI and PCI-X chipset integrated PATA ports.
PIO, MWDMA, UDMA
Early chipsets do not support LBA48 access for DMA. On PATA functions prior to revision 0xc5 the driver will use PIO when accessing those part of a large disk above the 137GB line.
Some systems have problems with ATAPI DMA. The cause is unknown, by default ATAPI DMA is therefore disabled.
atapi_dma = 0/1