Re: [PATCH v3 34/43] hw/intc: Add LoongArch extioi interrupt controller(EIOINTC)

[Richard Henderson]

On 5/11/22 02:54, yangxiaojuan wrote:
> On 2022/5/10 上午1:56, Richard Henderson wrote:
> > > > > +    case EXTIOI_IPMAP_START ... EXTIOI_IPMAP_END - 1:
> > > > > +        index = (offset - EXTIOI_IPMAP_START) >> 2;
> > > > > +        s->ipmap[index] = val;
> > > > > +        break;
> > > >
> > > > Do you need to recompute the entire interrupt map when ipmap changes?
> > > Sorry, could you explain it in more detail? i can not understand the meanning of 'the 
> > > entire interrupt map'?
> >
> > I mean, ipmap[*] and coremap[*] controls how isr[*] maps to the various cpus, as 
> > coreisr[*].  If either ipmap or coremap changes, do you need to re-compute coreisr[*] 
> > from the input isr[*]? 
>
> I think the interrupt has been handled by the core before set coremap or ipmap, and 
> coreisr[*] also has been set and cleard by original core.
> So,  the new mapped core need not  to update the coreisr[*].


Why do you believe that the core to which the interrupt is directed has interrupts 
enabled?  Why do you believe the core to which the interrupt is directed is the one that 
is changing the interrupt mapping?

I think your assumption is not correct.


r~