[PATCH 08/18] arm64: cpufeature: Add a feature for FIQ support

Hector Martin marcan at marcan.st
Mon Feb 8 10:51:09 EST 2021

On 08/02/2021 20.29, Marc Zyngier wrote:
> I'm not sure we want to trust the FW on that particular front (no
> offence intended...;-).

Hey, I don't even *use* the timers IRQs; if they are unmasked it's 
iBoot's fault! :-)

> That is my current take on this patch. Nothing in the arm64 kernel
> expects a FIQ today, so *when* a FIQ fires is pretty much irrelevant,
> as long as we handle it properly (panic). Keeping the two bits in sync
> is trivial, and shouldn't carry material overhead.

Sounds good then, and again that simplifies a ton of stuff. Will go for 
that in v2.

> Aside from the lack of programmable priority, the lack of convenient
> masking for per-CPU interrupts is a bit of an issue...

Yeah... we'll see how that goes.

Hector Martin (marcan at marcan.st)
Public Key: https://mrcn.st/pub

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