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To:     Joakim Zhang <qiangqing.zhang@nxp.com>
Subject: RE: [PATCH V3 2/2] drivers/irqchip: add NXP INTMUX interrupt  multiplexer support
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Date:   Fri, 20 Dec 2019 14:20:07 +0000
From:   Marc Zyngier <maz@kernel.org>
Cc:     Lokesh Vutla <lokeshvutla@ti.com>, <tglx@linutronix.de>,
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On 2019-12-20 14:10, Joakim Zhang wrote:
>> -----Original Message-----
>> From: Lokesh Vutla <lokeshvutla@ti.com>

[...]

>> Does the user care to which channel does the interrupt source goes 
>> to? If not,
>> interrupt-cells in DT can just be a single entry and the channel 
>> selection can be
>> controlled by the driver no? I am trying to understand why user 
>> should specify
>> the channel no.
> Hi Lokesh,
>
> If a fixed channel is specified in the driver, all interrupt sources
> will be connected to this channel, affecting the interrupt priority 
> to
> some extent.
>
> From my point of view, a fixed channel could be enough if don't care
> interrupt priority.

Hold on a sec:

Is the channel to which an interrupt is routed to programmable? What 
has
the priority of the interrupt to do with this? How does this affect
interrupt delivery?

It looks like this HW does more that you initially explained...

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