On Fri, Nov 09, 2007 at 04:49:16PM +0200, Török Edwin wrote: > There is one problem with force enabling ahci. You'll loose the CDROM on > Dell laptops. > Prior to force-enabling ahci there is one "device" that sees the 2 sata > channels, and the 2 ide channels. > When you force-enable ahci, this device becomes the ahci controller (it > changes the device id), > and the IDE controller will appear as a separate new device (with > another device id), but it is disabled. > > There are registers on the ICH7 that allows you to set enabled/disabled > status, but according to the documentation you should not enable a > device after it has been disabled. In practice I couldn't get the CDROM > to get re-enabled: > * either nothing happend > * spurious irqs were sent that nobody handles, unless I used irq=poll; > but still no cdrom. > > Force-enabling AHCI, and not trying to enable the CDROM works, although > I occasionally got NCQ errors. > > For a (long) discussion see this thread on the powertop mailing list: > http://www.bughost.org/pipermail/power/2007-June/000533.html > http://www.bughost.org/pipermail/power/2007-June/000573.html > > And there is also another slightly different approach: > http://mjg59.livejournal.com/76062.html > > Best regards, > --Edwin > In the MacBook, after enabling ahci the IDE controller also appeared as a separate new device, but it is enabled and handled correctly by piix. I haven't got any problem, even suspend/resume works fine. Lucky us who got the ABAR mapped by the BIOS... -- Riki Oktarianto - 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
