Re: [PATCH 3/6] irqchip: RISC-V Local Interrupt Controller Driver

From: Thomas Gleixner
Date: Thu Aug 02 2018 - 12:03:13 EST

On Thu, 2 Aug 2018, Christoph Hellwig wrote:
> On Thu, Aug 02, 2018 at 11:35:43AM +0200, Thomas Gleixner wrote:
> > So that's the low level per cpu interrupt/exception distribution mechanism,
> > i.e. a distinct per cpu 'vector' space with fixed functionality. It does
> > not make sense to actually handle that as an irq chip. It has absolutely no
> > relevance. The software interrupts are enabled when the CPU is started and
> > the external ones as well as they are gated by the PLIC.
> >
> > The only thing which might need to access the enable register is the local
> > timer interrupt. That really does not require an extra irq chip as the
> > enable/disable is really just at cpu up/down time and the magic happens on
> > the local CPU so no smp functional call hackery is required.
> >
> > The PLIC is the beast which wants a proper irqdomain/irqchip
> > implementation.
> And that is exactly what I've done in the repost.


> I need to polish the DT binding a little more and will repost later today.

Lemme go through that reposted series quickly.