RE: [PATCH] x86/i8259: Work around buggy legacy PIC

David Laight
2021-05-13T08:11:09Z

From: Maximilian Luz
> Sent: 12 May 2021 22:05
>
> The legacy PIC on the AMD variant of the Microsoft Surface Laptop 4 has
> some problems on boot. For some reason it consistently does not respond
> on the first try, requiring a couple more tries before it finally
> responds.

That seems very strange, something else must be going on that causes the grief.
The 8259 will be built into to the one of the cpu support chips.
I can't imagine that requires anything special.

It's not as though you have a real 8259 - which even a 286 can
break the inter-cycle recovery on (with the circuit from the
application note).

David

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