Messages in this thread | | | Date | Fri, 4 Apr 2014 19:34:31 +0200 | From | Ingo Molnar <> | Subject | Re: [BUG] x86: reboot doesn't reboot |
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* Matthew Garrett <mjg59@srcf.ucam.org> wrote:
> On Fri, Apr 04, 2014 at 08:13:48AM -0700, H. Peter Anvin wrote: > > On 04/04/2014 08:12 AM, Matthew Garrett wrote: > > > On Fri, Apr 04, 2014 at 09:27:48AM +0800, Li, Aubrey wrote: > > > > > >> The current situation is, > > >> - we have one(do we know more?) preproduction machine hangs by CF9. > > >> - We have more than one(could be thousand known) production machine > > >> works by CF9. > > > > > > Production hardware should never require CF9. > > > > > > > There are a lot of things that shouldn't be. > > Windows doesn't hit CF9, and production hardware is always tested with > Windows, so. [...]
So why the hell does the reboot function comment claim that the Windows reboot sequence (which is the de facto hardware standard) uses 0xcf9:
/* * 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
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