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Date:   Sat, 7 Jul 2018 14:16:06 +0800
From:   Guo Ren <ren_guo@c-sky.com>
To:     Mark Rutland <mark.rutland@arm.com>
Cc:     linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
        tglx@linutronix.de, daniel.lezcano@linaro.org,
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        gnu-csky@mentor.com, thomas.petazzoni@bootlin.com,
        wbx@uclibc-ng.org, green.hu@gmail.com
Subject: Re: [PATCH V2 16/19] csky: SMP support
Message-ID: <20180707061606.GA26276@guoren>
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On Fri, Jul 06, 2018 at 05:21:00PM +0100, Mark Rutland wrote:
> Please don't open-code this. Use of_device_is_available(), which checks
> the status property itself. e.g.
> 
> void __init setup_smp(void)
> {
> 	struct device_node *node = NULL;
> 
> 	while ((node = of_find_node_by_type(node, "cpu"))) {
> 		if (!of_device_is_available(node))
> 			continue;
> 
> 		...
> 	}
> }
Ok, approve.

> Please use the reg property, you need it to describe which particular
> CPUs are available.
> 
> You probably also want a mapping from Linux logical CPU id to your
> physical CPU id, and a sanity check on this. See arm64 for an example.
Yes, you are right. Reg property could determine which bit of CPU in
cr<0, 29> could be booted.

Thx for the tips.

 Guo Ren