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Date:   Tue, 16 May 2023 11:06:29 +0100
Message-ID: <86cz30mvyy.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Rich Felker <dalias@libc.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] irqchip/jcore-aic: Fix missing allocation of IRQ descriptors
In-Reply-To: <7e58646d7ae4cad32ae30e2e7b54806cc1272d63.camel@physik.fu-berlin.de>
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        <3c76bea5e45a5ae9ea58b3ff87f9971955a3a021.camel@physik.fu-berlin.de>
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On Thu, 11 May 2023 10:03:01 +0100,
John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> wrote:
> 
> On Thu, 2023-05-11 at 09:47 +0100, Marc Zyngier wrote:
> > On Thu, 11 May 2023 08:22:20 +0100,
> > John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> wrote:
> > > 
> > > Hi Jason!
> > 
> > ???
> 
> Sorry, I was confused by this:
> 
> > > > [- Jason]
> > > > 
> > > > It really begs the question: how has it ever been working before?
> > > 
> > > Users already used a locally patched kernel to work around this problem.
> > 
> > You're not answering my question. Does it mean JCore never worked
> > upstream?
> 
> It did still work which is why the previously suggested change was to make a
> failing call to irq_alloc_descs() non-fatal. The boards still booted
> up.

I don't get it. Either the descriptors are already allocated, and you
don't need this call, or they were never allocated and this never
worked. Which one is it?

> 
> > > > Is there any plan to modernise the port and get it to allocate
> > > > irq_descs on demand, as we do on most architectures?
> > > 
> > > Yes, there are plans to modernize the port. We're first working on
> > > upstreaming all kinds of patches that have been queuing up over the
> > > time.
> > 
> > I'd rather you skip that step and focus on making it work as a modern
> > architecture. This really looks like ARM circa 2007... :-/
> 
> We have a patch-set for switching it to device tree in the pipeline.

Again: why aren't we reviewing that instead of beating a long dead
horse?

	M.

-- 
Without deviation from the norm, progress is not possible.