* H. Peter Anvin <h...@zytor.com> wrote: > On April 4, 2014 9:32:58 AM PDT, Matthew Garrett <mj...@srcf.ucam.org> wrote: > > > Windows does ACPI first, so no. And the Dells were broken even > > before we moved ACPI up the list. > > That's not what you said a few posts ago.
Exactly, the claim ws: "Windows hits the keyboard controller and then tries the ACPI vector." Which is obviously not the same as 'Windows does ACPI first'. So the first step _has_ to be to document exactly what Windows does, because that's the hardware ABI that we cannot deviate from much. Or if we don't know a detail, document the specific uncertainties, don't pretend we know it! The current documented sequence lists 0xcf9, which seems to be a lie: /* * Windows compatible x86 hardware expects the following on reboot: * * 1) If the FADT has the ACPI reboot register flag set, try it * 2) If still alive, write to the keyboard controller * 3) If still alive, write to the ACPI reboot register again * 4) If still alive, write to the keyboard controller again * 5) If still alive, call the EFI runtime service to reboot * 6) If still alive, write to the PCI IO port 0xCF9 to reboot * 7) If still alive, inform BIOS to do a proper reboot Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/