Re: [RFC PATCH 1/5] RISC-V: Make IPI triggering flexible

From: Anup Patel
Date: Mon Sep 10 2018 - 23:37:17 EST


On Mon, Sep 10, 2018 at 7:04 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote:
> On Thu, Sep 06, 2018 at 04:15:14PM +0530, Anup Patel wrote:
>> This patch is doing two things:
>> 1. Allow IRQCHIP driver to provide IPI trigger mechanism
>
> And the big questions is why do we want that? The last thing we
> want is for people to "innovate" on how they deliver IPIs. RISC-V
> has defined an SBI interface for it to hide all the details, and
> we should not try to handle systems that are not SBI compliant.
>
> Eventuall we might want to revisit the SBI to improve on shortcomings
> if there are any, but we should not allow random irqchip drivers to
> override this.

I have already dropped this part from the PATCH v2.

>
>> 2. Have more generic IPI handler in arch/riscv so that IRQCHIP driver
>> can call it
>
> And that is rather irrelevant without 1) above.

Nopes, this is required for the RISC-V INTC driver.

Regards,
Anup