It appears that the DSDT tables and the related ASL files are present for few boareds in Linux BIOS. If so how are other boards expected to provide the required DSDT table. Does it has to be taken care either by the kernel or intiramfs ? Is Linux BIOS ACPI 3.0 compatible ?

The reason I am looking at this is for supporting PCIe hotplug which looks for _OSC method. This has been specified in ACPI 3.0 spec.