Re: More info on port 80 symptoms on MCP51 machine.

H. Peter Anvin
2007-12-12T21:10:31Z

Rene Herman wrote:
> On 12-12-07 21:26, Rene Herman wrote:
>
>> On 12-12-07 21:07, David P. Reed wrote:
>
>>> Someone might have an in to nVidia to clarify this, since I don't.
>>> In any case, the udelay(2) approach seems to be a safe fix for this
>>> machine.
>
> By the way, _does_ anyone have a contact at nVidia who could clarify?
> Alan maybe? I'm quite curious what they did...
>
> Summary:
>
> Unless after booting with "acpi=off", outputs to port 0x80 (the legacy
> way to delay I/O) reliably, but not immediately, hang MCP51 machines.
> Outputs to port 0xed do not indicating it's a not a generic bus abort
> problem.
>

Sorry, the first sentence didn't parse unambiguously for me. Do you
mean "acpi=off" works, or that "acpi=off" allows *subsequent* boots to work?

I have some people at nVidia I can probably ping.

-hpa