From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755938AbdGXNO0 (ORCPT ); Mon, 24 Jul 2017 09:14:26 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:60990 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755462AbdGXNOT (ORCPT ); Mon, 24 Jul 2017 09:14:19 -0400 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> Cc: linux-kernel@vger.kernel.org, will.deacon@arm.com, mark.rutland@arm.com, peterz@infradead.org, Rob Herring From: Marc Zyngier Organization: ARM Ltd Message-ID: Date: Mon, 24 Jul 2017 14:14:16 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <1500892161-17634-3-git-send-email-suzuki.poulose@arm.com> Content-Type: text/plain; charset=windows-1252 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); nit: Since you don't need the thread here, you can pass NULL instead. > + found = (cpu_node == np); > + of_node_put(np); > + if (found) > + break; > + } > + > + return cpu; > +} > +EXPORT_SYMBOL(of_device_node_get_cpu); > + > +/** > * __of_device_is_compatible() - Check if the node matches given constraints > * @device: pointer to node > * @compat: required compatible string, NULL or "" for any match > diff --git a/include/linux/of_device.h b/include/linux/of_device.h > index b4ad8b4..00a4ba9 100644 > --- a/include/linux/of_device.h > +++ b/include/linux/of_device.h > @@ -40,6 +40,8 @@ extern int of_device_request_module(struct device *dev); > extern void of_device_uevent(struct device *dev, struct kobj_uevent_env *env); > extern int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env); > > +extern int of_device_node_get_cpu(struct device_node *np); > + > static inline void of_device_node_put(struct device *dev) > { > of_node_put(dev->of_node); > @@ -110,6 +112,11 @@ static inline int of_dma_configure(struct device *dev, struct device_node *np) > } > static inline void of_dma_deconfigure(struct device *dev) > {} > + > +static inline int of_device_node_get_cpu(struct device_node *np) > +{ > + return nr_cpu_ids; > +} > #endif /* CONFIG_OF */ > > #endif /* _LINUX_OF_DEVICE_H */ > FWIW: Reviewed-by: Marc Zyngier M. -- Jazz is not dead. It just smells funny...