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From:   Anup Patel <anup@brainfault.org>
Date:   Tue, 11 Sep 2018 09:07:12 +0530
Message-ID: <CAAhSdy0zums9m4ZgSAv9GZuGE1iLfCfMbpjduZnNXQZu8uJZ5Q@mail.gmail.com>
Subject: Re: [RFC PATCH 1/5] RISC-V: Make IPI triggering flexible
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Palmer Dabbelt <palmer@sifive.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Jason Cooper <jason@lakedaemon.net>,
        Marc Zyngier <marc.zyngier@arm.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        "linux-kernel@vger.kernel.org List" <linux-kernel@vger.kernel.org>,
        Atish Patra <atish.patra@wdc.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-riscv@lists.infradead.org
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On Mon, Sep 10, 2018 at 7:04 PM, Christoph Hellwig <hch@infradead.org> 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