From mboxrd@z Thu Jan  1 00:00:00 1970
From: jszhang@marvell.com (Jisheng Zhang)
Date: Wed, 8 Jul 2015 19:38:42 +0800
Subject: [PATCH 4/4] arm: psci: add cpuidle_ops support
In-Reply-To: <20150708103429.GL7557@n2100.arm.linux.org.uk>
References: <1436350417-6712-1-git-send-email-jszhang@marvell.com>
 <1436350417-6712-5-git-send-email-jszhang@marvell.com>
 <20150708103429.GL7557@n2100.arm.linux.org.uk>
Message-ID: <20150708193842.1ca1c55a@xhacker>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Dear Russell,

On Wed, 8 Jul 2015 11:34:29 +0100
Russell King - ARM Linux <linux@arm.linux.org.uk> wrote:

> On Wed, Jul 08, 2015 at 06:13:37PM +0800, Jisheng Zhang wrote:
> > This patch implements cpuidle_ops using psci. After this patch, we can use
> > cpuidle-arm.c with psci backend for both arm and arm64.
> 
> I really don't see the point of most of the patches in this series.
> 
> To summarise, what you're doing is:
> 
> 1. Renaming arch/arm/kernel/psci_smp.c to arch/arm/kernel/psci.c
> 2. Adding a #ifdef CONFIG_SMP around _all_ the code in psci.c
> 3. Adding cpuidle code with an #ifdef CONFIG_CPU_IDLE around all the
>    CPU idle code.
> 
> So, we end up with a file which contains:
> 
> /*
>  header
>  */
> #include statements
> 
> /*
>  some commentry relevant to SMP code
>  */
> #ifdef CONFIG_CPU_IDLE
> ... cpu idle code ...
> #endif
> #ifdef CONFIG_SMP
> ... smp code ...
> #endif
> 
> which (a) is a mess, and (b) is unnecessary.  The only relevant bits which
> are shared are the #include statements.
> 
> Please try this alternative approach:
> 
> 1. Leave psci_smp.c alone.
> 2. Add arch/arm/kernel/psci_cpuidle.c containing the #include statements
>    you need, and the CPU idle code.
> 
> I think such an approach will reduce your patch series to two patches,
> one moving the ARM64 code, and one adding the cpuidle code.
> 

Good idea! Will refine the patches as you suggested.

Thanks a lot for your review,
Jisheng