From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932506AbdGXQmY (ORCPT ); Mon, 24 Jul 2017 12:42:24 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:35242 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752388AbdGXQmR (ORCPT ); Mon, 24 Jul 2017 12:42:17 -0400 Cc: Sudeep Holla , mark.rutland@arm.com, peterz@infradead.org, will.deacon@arm.com, linux-kernel@vger.kernel.org, Rob Herring Subject: Re: [PATCH v2 2/6] of: Add helper for mapping device node to logical CPU number To: Suzuki K Poulose , linux-arm-kernel@lists.infradead.org References: <1500892161-17634-1-git-send-email-suzuki.poulose@arm.com> <1500892161-17634-3-git-send-email-suzuki.poulose@arm.com> From: Sudeep Holla Organization: ARM Message-ID: <7ec47d12-3b6b-82c0-ba15-5664b5169974@arm.com> Date: Mon, 24 Jul 2017 17:42:14 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <1500892161-17634-3-git-send-email-suzuki.poulose@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24/07/17 11:29, Suzuki K Poulose wrote: > Add a helper to map a device node to a logical CPU number to avoid > duplication. Currently this is open coded in different places (e.g > gic-v3, coresight). The helper tries to map device node to a "possible" > logical CPU id, which may not be online yet. It is the responsibility > of the user to make sure that the CPU is online. The helper uses > of_get_cpu_node() which uses arch specific backends to match the phyiscal > ids. > > Cc: Rob Herring > Cc: Mark Rutland > Signed-off-by: Suzuki K Poulose > --- > drivers/of/base.c | 26 ++++++++++++++++++++++++++ > include/linux/of_device.h | 7 +++++++ > 2 files changed, 33 insertions(+) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 686628d..639af23 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -420,6 +420,32 @@ struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) > EXPORT_SYMBOL(of_get_cpu_node); > > /** > + * of_device_node_get_cpu: Get the logical CPU number for a given device_node > + * > + * @cpu_node: Pointer to the device_node for CPU. > + * > + * Returns the logical CPU number of the given CPU device_node. > + * Returns >= nr_cpu_ids if CPU is not found. > + */ > +int of_device_node_get_cpu(struct device_node *cpu_node) > +{ > + int cpu, thread; > + bool found = false; > + struct device_node *np; > + > + for_each_possible_cpu(cpu) { > + np = of_get_cpu_node(cpu, &thread); Ideally, we should be able to use of_cpu_device_node_get instead of of_get_cpu_node which parses the device tree. Not sure if that's the case here too. Sorry for following up on this so late. I had a patch in my tree for-a-while to address that. Just posted it[1] now seeing this patch now. You can move to of_cpu_device_node_get if all users of this function are called after CPU's are registered. Otherwise, you can keep it as is for now and it can be changed once [1] lands. -- Regards, Sudeep [1] https://marc.info/?l=devicetree&m=150090452130567&w=2