Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755353Ab3GOKY1 (ORCPT ); Mon, 15 Jul 2013 06:24:27 -0400 Received: from service87.mimecast.com ([91.220.42.44]:33788 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755133Ab3GOKWZ (ORCPT ); Mon, 15 Jul 2013 06:22:25 -0400 From: Sudeep.KarkadaNagesha@arm.com To: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: cpufreq@vger.kernel.org, arnd@arndb.de, olof@lixom.net, lorenzo.pieralisi@arm.com, rob.herring@calxeda.com, grant.likely@linaro.org, rjw@sisk.pl, viresh.kumar@linaro.org, gregkh@linuxfoundation.org, gregory.clement@free-electrons.com, kernel@pengutronix.de, shawn.guo@linaro.org, linux@arm.linux.org.uk, Sudeep KarkadaNagesha Subject: [RFC PATCH 02/11] ARM: DT/kernel: define ARM specific arch_of_get_cpu_node Date: Mon, 15 Jul 2013 11:22:03 +0100 Message-Id: <1373883732-26303-3-git-send-email-Sudeep.KarkadaNagesha@arm.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1373883732-26303-1-git-send-email-Sudeep.KarkadaNagesha@arm.com> References: <1373883732-26303-1-git-send-email-Sudeep.KarkadaNagesha@arm.com> X-OriginalArrivalTime: 15 Jul 2013 10:22:19.0346 (UTC) FILETIME=[2FB54B20:01CE8145] X-MC-Unique: 113071511222309901 Content-Type: text/plain; charset=WINDOWS-1252 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id r6FAP0XR007661 Content-Length: 2630 Lines: 81 From: Sudeep KarkadaNagesha CPU subsystem now provides architecture specific hook to retrieve the of_node. Most of the cpu DT node parsing and initialisation is contained in devtree.c. It's better to contain all CPU device node parsing there. arch_of_get_cpu_node is mainly used to assign cpu->of_node when CPUs get registered. This patch overrides the defination of the same. It can also act as the helper function in pre-SMP/early initialisation stages to retrieve CPU device node pointers in logical ordering. This mainly helps to avoid replication of the code doing CPU node parsing and physical(MPIDR) to logical mapping. Signed-off-by: Sudeep KarkadaNagesha --- arch/arm/include/asm/prom.h | 1 + arch/arm/kernel/devtree.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/arch/arm/include/asm/prom.h b/arch/arm/include/asm/prom.h index a219227..96f1682 100644 --- a/arch/arm/include/asm/prom.h +++ b/arch/arm/include/asm/prom.h @@ -18,6 +18,7 @@ extern struct machine_desc *setup_machine_fdt(unsigned int dt_phys); extern void arm_dt_memblock_reserve(void); extern void __init arm_dt_init_cpu_maps(void); +extern struct device_node *arch_of_get_cpu_node(int cpu); #else /* CONFIG_OF */ diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c index 5859c8b..3431aa9 100644 --- a/arch/arm/kernel/devtree.c +++ b/arch/arm/kernel/devtree.c @@ -169,6 +169,35 @@ void __init arm_dt_init_cpu_maps(void) } } +struct device_node * __init arch_of_get_cpu_node(int cpu) +{ + struct device_node *cpun, *cpus; + const u32 *cell; + u64 hwid; + int ac; + + cpus = of_find_node_by_path("/cpus"); + if (WARN(!cpus, "Missing cpus node, bailing out\n")) + return NULL; + + if (WARN_ON(of_property_read_u32(cpus, "#address-cells", &ac))) + ac = of_n_addr_cells(cpus); + + for_each_child_of_node(cpus, cpun) { + if (of_node_cmp(cpun->type, "cpu")) + continue; + cell = of_get_property(cpun, "reg", NULL); + if (WARN(!cell, "%s: missing reg property\n", cpun->full_name)) + continue; + + hwid = of_read_number(cell, ac); + if ((hwid & MPIDR_HWID_BITMASK) == cpu_logical_map(cpu)) + return cpun; + } + + return NULL; +} + /** * setup_machine_fdt - Machine setup when an dtb was passed to the kernel * @dt_phys: physical address of dt blob -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/