From patchwork Tue Oct 6 15:32:17 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arun Bharadwaj X-Patchwork-Id: 35121 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from bilbo.ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id 110A9B8311 for ; Wed, 7 Oct 2009 02:32:43 +1100 (EST) Received: from e28smtp02.in.ibm.com (e28smtp02.in.ibm.com [59.145.155.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp02.in.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 91AC4B7BC7 for ; Wed, 7 Oct 2009 02:32:35 +1100 (EST) Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by e28smtp02.in.ibm.com (8.14.3/8.13.1) with ESMTP id n96FWTrH010884 for ; Tue, 6 Oct 2009 21:02:29 +0530 Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id n96FWTBI2552062 for ; Tue, 6 Oct 2009 21:02:29 +0530 Received: from d28av03.in.ibm.com (loopback [127.0.0.1]) by d28av03.in.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id n96FWRWg014971 for ; Wed, 7 Oct 2009 02:32:29 +1100 Received: from linux.vnet.ibm.com ([9.77.122.245]) by d28av03.in.ibm.com (8.14.3/8.13.1/NCO v10.0 AVin) with ESMTP id n96FWIpD014792 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Wed, 7 Oct 2009 02:32:22 +1100 Date: Tue, 6 Oct 2009 21:02:17 +0530 From: Arun R Bharadwaj To: Peter Zijlstra , Joel Schopp , Benjamin Herrenschmidt , Paul Mackerras , Ingo Molnar , Vaidyanathan Srinivasan , Dipankar Sarma , Balbir Singh , Gautham R Shenoy , Venkatesh Pallipadi , Arun Bharadwaj Subject: [v7 PATCH 4/7]: POWER: enable cpuidle for POWER. Message-ID: <20091006153217.GB7343@linux.vnet.ibm.com> References: <20091006152421.GA7278@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20091006152421.GA7278@linux.vnet.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) Cc: linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.12 Precedence: list Reply-To: arun@linux.vnet.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org * Arun R Bharadwaj [2009-10-06 20:54:21]: This patch enables the cpuidle option in Kconfig for pSeries. Currently cpuidle infrastructure is enabled only for x86 and ARM. This code is almost completely borrowed from x86 to enable cpuidle for pSeries. Signed-off-by: Arun R Bharadwaj --- arch/powerpc/Kconfig | 17 +++++++++++++++++ arch/powerpc/include/asm/system.h | 2 ++ arch/powerpc/kernel/idle.c | 19 +++++++++++++++++++ 3 files changed, 38 insertions(+) Index: linux.trees.git/arch/powerpc/Kconfig =================================================================== --- linux.trees.git.orig/arch/powerpc/Kconfig +++ linux.trees.git/arch/powerpc/Kconfig @@ -88,6 +88,9 @@ config ARCH_HAS_ILOG2_U64 bool default y if 64BIT +config ARCH_HAS_CPU_IDLE_WAIT + def_bool y + config GENERIC_HWEIGHT bool default y @@ -243,6 +246,20 @@ source "kernel/Kconfig.freezer" source "arch/powerpc/sysdev/Kconfig" source "arch/powerpc/platforms/Kconfig" +menu "Power management options" + +source "drivers/cpuidle/Kconfig" + +config PSERIES_PROCESSOR_IDLE + bool "Idle Power Management Support for pSeries" + depends on PPC_PSERIES && CPU_IDLE + default y + help + Idle Power Management Support for pSeries. This hooks onto cpuidle + infrastructure to help in idle cpu power management. + +endmenu + menu "Kernel options" config HIGHMEM Index: linux.trees.git/arch/powerpc/include/asm/system.h =================================================================== --- linux.trees.git.orig/arch/powerpc/include/asm/system.h +++ linux.trees.git/arch/powerpc/include/asm/system.h @@ -546,5 +546,7 @@ extern void account_system_vtime(struct extern struct dentry *powerpc_debugfs_root; +void cpu_idle_wait(void); + #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_SYSTEM_H */ Index: linux.trees.git/arch/powerpc/kernel/idle.c =================================================================== --- linux.trees.git.orig/arch/powerpc/kernel/idle.c +++ linux.trees.git/arch/powerpc/kernel/idle.c @@ -102,6 +102,25 @@ void cpu_idle(void) } } +static void do_nothing(void *unused) +{ +} + +/* + * cpu_idle_wait - Used to ensure that all the CPUs come out of the old + * idle loop and start using the new idle loop. + * Required while changing idle handler on SMP systems. + * Caller must have changed idle handler to the new value before the call. + */ +void cpu_idle_wait(void) +{ + /* Ensure that new value of ppc_md.power_save is set */ + smp_mb(); + /* kick all the CPUs so that they exit out of ppc_md.power_save */ + smp_call_function(do_nothing, NULL, 1); +} +EXPORT_SYMBOL_GPL(cpu_idle_wait); + int powersave_nap; #ifdef CONFIG_SYSCTL