linux-kernel - Re: [PATCH 1/2] ARM: cpuidle: fix !cpuidle

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Date:	Wed, 30 Mar 2016 10:09:12 +0200
From:	Daniel Lezcano <daniel.lezcano@...aro.org>
To:	Jisheng Zhang <jszhang@...vell.com>
Cc:	linux@....linux.org.uk, linux-arm-kernel@...ts.infradead.org,
	linux-kernel@...r.kernel.org,
	Lorenzo Pieralisi <Lorenzo.Pieralisi@....com>,
	Catalin Marinas <Catalin.Marinas@....com>
Subject: Re: [PATCH 1/2] ARM: cpuidle: fix !cpuidle_ops[cpu].init case during
 init

On 03/30/2016 09:16 AM, Jisheng Zhang wrote:
> Hi Daniel,

[ ... ]

Added Lorenzo and Catalin.

>> Hi Jisheng,
>>
>> this should be handled in the arm_cpuidle_read_ops function.
>>
>
> Thanks for reviewing. After some consideration, I think this patch isn't correct
> There may be platforms which doesn't need the init member at all, although
> currently I don't see such platforms in mainline, So I'll drop this patch
> and send out one v2 only does the optimization.

There is an inconsistency between ARM and ARM64. The 'cpu_get_ops', the 
arm_cpuidle_read_ops from the ARM64 side, returns -EOPNOTSUPP when the 
init function is not there for cpuidle.

I don't think it is a problem, but as ARM/ARM64 are sharing the same 
cpuidle-arm.c driver it would make sense to unify the behavior between 
both archs.


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