Alan Cox wrote: > On Mon, 23 Apr 2007 02:41:06 +0900 > Tejun Heo <htejun@xxxxxxxxx> wrote: > >> Whether a controller needs IDE or SATA ACPI hierarchy is determined by >> the programming interface of the controller not by whether the >> controller is SATA or PATA > > NAK > > I keep trying to point out that this is not true. > > The ACPI interface to use can only be safely determined one way - and > that is to see what methods the BIOS has attached to the device and use > those. > > Take the ACPI handle, go look for _GTF, _SDD etc and believe the > firmware. Nothing else works. Actually, that's dangerous. For example, you must not do _STM/_GTM on ahci becuase _STM/_GTM access PCI config registers which must not be accessed in achi modes and some BIOSen supply the same _STM/_GTM nodes whether the controller is in ata_piix mode or ahci mode. Also, on ICH8, the association gets quite weird due to PCI device splitting. The ACPI spec says the layout is dependent on controller interface and I can see reasons why we need to follow that but not the other way around. Do you have counter-examples? -- tejun - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
