Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII;
 format=flowed
Content-Transfer-Encoding: 7bit
Date:   Wed, 11 Nov 2020 14:19:40 +0000
From:   Marc Zyngier <maz@kernel.org>
To:     Linus Walleij <linus.walleij@linaro.org>
Cc:     Daniel Palmer <daniel@0x0f.com>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 3/5] gpio: msc313: MStar MSC313 GPIO driver
In-Reply-To: <CACRpkdaTknFRSm4pcSf-v7Be8A_SnMMrhegu6W67gUjOJVLEBQ@mail.gmail.com>
References: <20201019141008.871177-1-daniel@0x0f.com>
 <20201019141008.871177-4-daniel@0x0f.com>
 <CACRpkdZNr6sDqJhg3KcX0bCbcd8fh2gXFYbS1r2H2Sq+vGqjUw@mail.gmail.com>
 <3fd04aeb5047d8059ddecc1eda19c2e4@kernel.org>
 <CAFr9PX=vxCCQgCWe9FPb6Z=0=a48HwGOfM_uOG3SqGN9VSYQUA@mail.gmail.com>
 <71f3632bee262a18e1b7edb74980ae9a@kernel.org>
 <CACRpkdYr+yhyROQzaYfFrGwG74DuZiA=fMVOesgOKrDajhTodQ@mail.gmail.com>
 <bc0ab2f10bb72fe5b455ca12958f6444@kernel.org>
 <CACRpkdaTknFRSm4pcSf-v7Be8A_SnMMrhegu6W67gUjOJVLEBQ@mail.gmail.com>
User-Agent: Roundcube Webmail/1.4.9
Message-ID: <40fec073b2423b698ef4d91c499c7c9f@kernel.org>
Precedence: bulk

On 2020-11-11 14:09, Linus Walleij wrote:
> On Tue, Nov 10, 2020 at 3:19 PM Marc Zyngier <maz@kernel.org> wrote:
>> On 2020-11-10 14:02, Linus Walleij wrote:
> 
>> >> Probably nothing more than setting the callback to
>> >> irq_chip_set_affinity_parent,
>> >
>> > Hm, is this something all GPIO irqchips used on SMP systems
>> > should be doing? Or just hierarchical ones?
>> 
>> Probably only the hierarchical ones. I'd expect the non-hierarchical
>> GPIOs to be muxed behind a single interrupt, which makes it impossible
>> to move a single GPIO around, and moving the mux interrupt would break
>> userspace's expectations that interrupts move independently of each
>> others.
> 
> I found two suspects and sent patches. I think I might have some
> more candidates down in pinctrl. I do have some hierarchical IRQ
> that is on UP systems, I suppose these are not affected.

Yup, they look good. Feel free to add my Ack to them.
And yes, UP systems are naturally oblivious of interrupt affinity.

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...