Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler

From	Guenter Roeck <linux@roeck-us.net>
Newsgroups	linux.kernel
Subject	Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler
Date	2016-04-14 15:30 +0200
Message-ID	<rnPvl-2fL-23@gated-at.bofh.it> (permalink)
References	(2 earlier) <rnqQh-jn-3@gated-at.bofh.it> <rnsS7-1JU-25@gated-at.bofh.it> <rnt1M-1O6-7@gated-at.bofh.it> <rnDDP-1uB-11@gated-at.bofh.it> <rnLi3-7rI-25@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 04/14/2016 01:52 AM, Wolfram Sang wrote:
>
>> That makes things quite tricky. Best I can think of is a series of boolean
>> devicetree properties, such as
>>
>> 	broken-reset-handler
>> 	last-resort-restart-handler
>> 	secondary-restart-handler
>> 	default-restart-handler
>> 	primary-restart-handler
>>
>> which ends up being quite similar to the 'restart-priority' property. I'll
>> do this as follow-up patch, though
>
> Please CC me on this. I wanted to tackle this problem as well today. My

Sure.

> findings/conclusions so far:
>
> * There is one driver bringing 'priority' directly to DT already: gpio-restart
>
Correct.

> * Watchdog priorities are board dependant
>
> * Having the priorities clear at boot-time is safer than configuring them
>    at run-time
>
Correct.

> * The linux scheme (0-255) shouldn't be enforced in DT
>
> So, I wondered about a "priority" binding which just states "the higher,
> the more important". Then any OS can decide what to do with it. In the
> Linux case, this could be: sort them and give them priority 256 -
> position_in_sorted_list.
>

"the higher, the more important" makes sense to me. We don't have to
enforce the linux scheme, though that happens to be the same (the priority
argument in the notifier block takes an int, so it would not even be
necessary to adjust it unless someone specifies 0xffffffff).

> Opinions?
>
I am fine either way - boolean properties or numbers, with a personal
preference for numbers as more flexible. Whatever is acceptable for
the community is fine with me.

Guenter

>> - I do not see the point holding up the series for this, and it is
>> really a separate problem.
>
> Ack.
>

Thread

[PATCH 0/6] ARM/ARM64: Drop arm_pm_restart Guenter Roeck <linux@roeck-us.net> - 2016-04-08 15:00 +0200
  [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Guenter Roeck <linux@roeck-us.net> - 2016-04-08 15:00 +0200
    Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Wolfram Sang <wsa@the-dreams.de> - 2016-04-12 17:40 +0200
    Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Mark Rutland <mark.rutland@arm.com> - 2016-04-13 13:10 +0200
      Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Jisheng Zhang <jszhang@marvell.com> - 2016-04-13 13:40 +0200
      Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Guenter Roeck <linux@roeck-us.net> - 2016-04-13 15:20 +0200
        Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Geert Uytterhoeven <geert@linux-m68k.org> - 2016-04-13 15:30 +0200
          Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Guenter Roeck <linux@roeck-us.net> - 2016-04-14 02:50 +0200
            Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Wolfram Sang <wsa@the-dreams.de> - 2016-04-14 11:00 +0200
              Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Guenter Roeck <linux@roeck-us.net> - 2016-04-14 15:30 +0200
                Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler Wolfram Sang <wsa@the-dreams.de> - 2016-04-14 16:40 +0200
  [PATCH 1/6] ARM: prima2: Register with kernel restart handler Guenter Roeck <linux@roeck-us.net> - 2016-04-08 15:00 +0200
  [PATCH 6/6] ARM: Remove arm_pm_restart Guenter Roeck <linux@roeck-us.net> - 2016-04-08 15:00 +0200
  [PATCH 4/6] ARM: Register with kernel restart handler Guenter Roeck <linux@roeck-us.net> - 2016-04-08 15:00 +0200
  [PATCH 5/6] ARM64: Remove arm_pm_restart Guenter Roeck <linux@roeck-us.net> - 2016-04-08 15:00 +0200
    Re: [PATCH 5/6] ARM64: Remove arm_pm_restart Catalin Marinas <catalin.marinas@arm.com> - 2016-04-12 15:20 +0200
  Re: [PATCH 0/6] ARM/ARM64: Drop arm_pm_restart Wolfram Sang <wsa@the-dreams.de> - 2016-04-08 17:50 +0200
  Re: [PATCH 0/6] ARM/ARM64: Drop arm_pm_restart Arnd Bergmann <arnd@arndb.de> - 2016-04-08 22:50 +0200
  Re: [PATCH 0/6] ARM/ARM64: Drop arm_pm_restart Wolfram Sang <wsa@the-dreams.de> - 2016-04-12 17:50 +0200

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