From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andre Przywara <andre.przywara@linaro.org>
Subject: Re: [PATCH v2 2/6] arm: move GIC SGI kicking into
	separate function
Date: Mon, 02 Dec 2013 14:24:15 +0100
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To: Julien Grall <julien.grall@linaro.org>
Cc: xen-devel@lists.xenproject.org, patches@linaro.org, Ian.Campbell@citrix.com, stefano.stabellini@eu.citrix.com
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On 12/02/2013 02:16 PM, Julien Grall wrote:
>
>
> On 12/02/2013 11:08 AM, Andre Przywara wrote:
>> Currently we unconditionally send SGIs to all cores on SMP bringup.
>> PSCI will not need this, so we move this into a function and call it
>> explicitly from the platforms that need it. This gets us get rid of
>> the empty cpu_up() platform functions in ARM32 and the comment in
>> there.
>>
>> Signed-off-by: Andre Przywara <andre.przywara@linaro.org>
>> ---
>>   xen/arch/arm/arm64/smpboot.c      |  2 +-
>>   xen/arch/arm/platform.c           |  2 +-
>>   xen/arch/arm/platforms/exynos5.c  | 11 +----------
>>   xen/arch/arm/platforms/omap5.c    | 11 +----------
>>   xen/arch/arm/platforms/vexpress.c | 10 +---------
>>   xen/arch/arm/smpboot.c            | 15 ++++++++++-----
>>   xen/include/asm-arm/smp.h         |  2 ++
>>   7 files changed, 17 insertions(+), 36 deletions(-)
>>
>
> [..]
>
>> diff --git a/xen/arch/arm/platform.c b/xen/arch/arm/platform.c
>> index a7f9ee4..056d462 100644
>> --- a/xen/arch/arm/platform.c
>> +++ b/xen/arch/arm/platform.c
>> @@ -112,7 +112,7 @@ int __init platform_cpu_up(int cpu)
>>       if ( platform && platform->cpu_up )
>>           return platform->cpu_up(cpu);
>>
>> -    return -EAGAIN;
>> +    return -ENODEV;
>
> This change seems unrelated to this patch.

That is disputable. If I read the original code directly, the intention 
of EAGAIN was like: "There is no platform specific code, try something 
else." Now with PSCI and the GIC kicking already folded into this 
function, the answer to "no PSCI and no platform code" is simply: I 
don't know how to enable SMP, so there is no SMP => ENODEV.

I can add a comment if this helps.

Regards,
Andre.