The
stpcide driver supports the STMicroelectronics STPC x86 SoC internal IDE controllers, and provides the interface with the hardware for the
ata(4) driver. The driver features DMA mode 2 and PIO mode 4 transfer speeds.
The 0x0002 flag forces the
stpcide driver to disable DMA on chipsets for which DMA would normally be enabled. This can be used as a debugging aid, or to work around problems where the IDE controller is wired up to the system incorrectly.