From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751713AbZHSM6o (ORCPT ); Wed, 19 Aug 2009 08:58:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751467AbZHSM6n (ORCPT ); Wed, 19 Aug 2009 08:58:43 -0400 Received: from e28smtp01.in.ibm.com ([59.145.155.1]:44146 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751446AbZHSM6m (ORCPT ); Wed, 19 Aug 2009 08:58:42 -0400 Date: Wed, 19 Aug 2009 18:28:36 +0530 From: Arun R Bharadwaj To: Joel Schopp , Benjamin Herrenschmidt , Shaohua Li , Venkatesh Pallipadi , Adam Belay , Peter Zijlstra , Ingo Molnar , Vaidyanathan Srinivasan , Dipankar Sarma , Balbir Singh , Gautham R Shenoy , Arun Bharadwaj Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH 1/2]: pSeries: Enable cpuidle for pSeries. Message-ID: <20090819125836.GB20627@linux.vnet.ibm.com> Reply-To: arun@linux.vnet.ibm.com References: <20090819125716.GA20627@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20090819125716.GA20627@linux.vnet.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Arun R Bharadwaj [2009-08-19 18:27:16]: This patch enables the cpuidle option in Kconfig for pSeries. It also adds the routine cpu_idle_wait. Signed-off-by: Arun R Bharadwaj --- arch/powerpc/Kconfig | 18 ++++++++++++++++++ arch/powerpc/include/asm/system.h | 2 ++ arch/powerpc/platforms/pseries/setup.c | 20 ++++++++++++++++++++ drivers/cpuidle/cpuidle.c | 1 + 4 files changed, 41 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 +246,21 @@ source "kernel/Kconfig.freezer" source "arch/powerpc/sysdev/Kconfig" source "arch/powerpc/platforms/Kconfig" +menu "Power management options" + +source "drivers/cpuidle/Kconfig" + +config TPMD + tristate "TPMD power management support" + depends on PPC_PSERIES && CPU_IDLE + default y + help + Thermal and Power Management Devices (TPMD). This hooks onto cpuidle + infrastructure to help in idle cpu power management. Currently this + is enabled only for pSeries. + +endmenu + menu "Kernel options" config HIGHMEM Index: linux.trees.git/drivers/cpuidle/cpuidle.c =================================================================== --- linux.trees.git.orig/drivers/cpuidle/cpuidle.c +++ linux.trees.git/drivers/cpuidle/cpuidle.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "cpuidle.h" Index: linux.trees.git/arch/powerpc/platforms/pseries/setup.c =================================================================== --- linux.trees.git.orig/arch/powerpc/platforms/pseries/setup.c +++ linux.trees.git/arch/powerpc/platforms/pseries/setup.c @@ -278,6 +278,26 @@ static struct notifier_block pci_dn_reco .notifier_call = pci_dn_reconfig_notifier, }; +static void do_nothing(void *unused) +{ +} + +/* + * cpu_idle_wait - Used to ensure that all the CPUs discard old value of + * pm_idle and update to new pm_idle value. Required while changing pm_idle + * handler on SMP systems. + * + * Caller must have changed pm_idle to the new value before the call. Old + * pm_idle value will not be used by any CPU after the return of this function. + */ +void cpu_idle_wait(void) +{ + smp_mb(); + /* kick all the CPUs so that they exit out of pm_idle */ + smp_call_function(do_nothing, NULL, 1); +} +EXPORT_SYMBOL_GPL(cpu_idle_wait); + static void __init pSeries_setup_arch(void) { /* Discover PIC type and setup ppc_md accordingly */ 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 */