Re: [PATCH v6 13/17] powerpc/pseries/vas: Setup IRQ and fault handling

Excerpts from Haren Myneni's message of June 18, 2021 12:09 pm:

On Fri, 2021-06-18 at 09:34 +1000, Nicholas Piggin wrote:

quoted

Excerpts from Haren Myneni's message of June 18, 2021 6:37 am:

quoted

NX generates an interrupt when sees a fault on the user space
buffer and the hypervisor forwards that interrupt to OS. Then
the kernel handles the interrupt by issuing H_GET_NX_FAULT hcall
to retrieve the fault CRB information.

This patch also adds changes to setup and free IRQ per each
window and also handles the fault by updating the CSB.

In as much as this pretty well corresponds to the PowerNV code
AFAIKS,
it looks okay to me.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>

Could you have an irq handler in your ops vector and have 
the core code set up the irq and call your handler, so the Linux irq
handling is in one place? Not something for this series, I was just
wondering.

Not possible to have common core code for IRQ  setup. 

PowerNV: Every VAS instance will be having IRQ and this setup will be
done during initialization (system boot). A fault FIFO will be assigned
for each instance and registered to VAS so that VAS/NX writes fault CRB
into this FIFO.  

PowerVM: Each window will have an IRQ and the setup will be done during
window open. 

Yeah, I thought as much. Just wondering.

Thanks,
Nick