Subject: Re: [RFC] irqchip: add support for LS1021A external interrupt lines
To: Alexander Stein <alexander.stein@systec-electronic.com>
CC: Marc Zyngier <marc.zyngier@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Jason Cooper <jason@lakedaemon.net>, Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>, <linux-kernel@vger.kernel.org>,
        <devicetree@vger.kernel.org>
References: <48d2d08c-c57a-ce49-5958-0fd5ad4a2dc7@arm.com>
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From: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Message-ID: <42019fb5-393a-08b0-924d-bf1a97e078fe@prevas.dk>
Date: Mon, 11 Dec 2017 14:45:39 +0100
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On 2017-12-11 11:02, Alexander Stein wrote:

> Oh, and what is the content of register SCFG_SCFGREVCR?

Good point. On my board it's 0xffffffff, set even before U-boot starts,
and lots board support code in U-boot expects this. I can't immediately
find examples in the linux source code that actually writes to the scfg,
so I don't know if we already have that as an implicit assumption as
well. But it would be kind of nasty to have to make the code read
SCFG_SCFGREVCR and decide the bit pattern to use based on that -
especially since I wouldn't be able to test it.

Who thought such a magic switch could ever be a good idea?

-- 
Rasmus Villemoes
Software Developer
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