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Subject: Re: [PATCH v2 0/2] Add a watchdog driver that uses ARM Secure Monitor
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To:     Julius Werner <jwerner@chromium.org>,
        Evan Benn <evanbenn@chromium.org>
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        Xingyu Chen <xingyu.chen@amlogic.com>,
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From:   Florian Fainelli <f.fainelli@gmail.com>
Message-ID: <9d029a04-2a37-cbbe-1932-be34d34f6b69@gmail.com>
Date:   Wed, 15 Apr 2020 20:48:04 -0700
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On 4/15/2020 5:56 PM, Julius Werner wrote:
>> Can anyone provide advice about making SMCWD_FUNC_ID a device tree
>> param directly, vs using the compatible to select from a table.
> 
> Sounds like most people prefer the way with using different compatible
> strings? (Personally I don't really care either way.)

The PSCI binding itself has provision for specifying function IDs for 
different functions, and this seems to be followed by other subsystems 
as well like SCMI:

https://www.spinics.net/lists/arm-kernel/msg791270.html

I could easily imagine that a firmware would provide two functions IDs 
(one for AArch32, one for AArch64) and that it could change those over 
time while not changing the compatible string at all.
-- 
Florian