From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752071AbaLIS50 (ORCPT ); Tue, 9 Dec 2014 13:57:26 -0500 Received: from e8.ny.us.ibm.com ([32.97.182.138]:43299 "EHLO e8.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752000AbaLIS5W (ORCPT ); Tue, 9 Dec 2014 13:57:22 -0500 From: "Shreyas B. Prabhu" To: linux-kernel@vger.kernel.org Cc: "Shreyas B. Prabhu" , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , "Rafael J. Wysocki" , linux-pm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Vaidyanathan Srinivasan , Preeti U Murthy Subject: [PATCH v4 0/4] powernv: cpuidle: Redesign idle states management Date: Wed, 10 Dec 2014 00:26:49 +0530 Message-Id: <1418151413-6141-1-git-send-email-shreyas@linux.vnet.ibm.com> X-Mailer: git-send-email 1.9.3 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14120918-0029-0000-0000-0000015FA0CA Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Deep idle states like sleep and winkle are per core idle states. A core enters these states only when all the threads enter either the particular idle state or a deeper one. There are tasks like fastsleep hardware bug workaround and hypervisor core state save which have to be done only by the last thread of the core entering deep idle state and similarly tasks like timebase resync, hypervisor core register restore that have to be done only by the first thread waking up from these states. The current idle state management does not have a way to distinguish the first/last thread of the core waking/entering idle states. Tasks like timebase resync are done for all the threads. This is not only is suboptimal, but can cause functionality issues when subcores are involved. Winkle is deeper idle state compared to fastsleep. In this state the power supply to the chiplet, i.e core, private L2 and private L3 is turned off. This results in a total hypervisor state loss. This patch set adds support for winkle and provides a way to track the idle states of the threads of the core and use it for idle state management of idle states sleep and winkle. Note- This patch set requires "powerpc: powernv: Return to cpu offline loop when finished in KVM guest" (http://patchwork.ozlabs.org/patch/417240/) TBD: ---- - Remove duplication of branching to kvm code. Changes in v4: -------------- - Based patches on top of http://patchwork.ozlabs.org/patch/417240/ - isync ordering fix. - Save/Restore SRR1 value so that it doesn't get clobbered by opal_call_realmode. - Changed HSPRG0 handling. - Comment fixes. Changes in v3: ------------- - Added barriers after lock - Added a paca field to that stores thread mask. - Changed code structure around fastsleep workaround, to allow for manual patching out if the platform does not require it. - Threads waiting on core_idle_state lock now loop in HMT_LOW - Using NV CRs to avoid save/restore of CR while making OPAL calls. - Fixed couple of flow issues in path where fastsleep workaround was not needed - Using PPC_LR_STKOFF instead of _LINK in opal_call_realmode - Restoring WORT and WORC Changes in v2: -------------- -Using PNV_THREAD_NAP/SLEEP defines while calling power7_powersave_common -Comment changes based on review -Rebased on top of 3.18-rc6 Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Rafael J. Wysocki Cc: linux-pm@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: Vaidyanathan Srinivasan Cc: Preeti U Murthy Paul Mackerras (1): powerpc: powernv: Switch off MMU before entering nap/sleep/rvwinkle mode Preeti U. Murthy (1): powerpc/powernv: Enable Offline CPUs to enter deep idle states Shreyas B. Prabhu (2): powernv: cpuidle: Redesign idle states management powernv: powerpc: Add winkle support for offline cpus arch/powerpc/include/asm/cpuidle.h | 14 ++ arch/powerpc/include/asm/opal.h | 13 + arch/powerpc/include/asm/paca.h | 6 + arch/powerpc/include/asm/ppc-opcode.h | 2 + arch/powerpc/include/asm/processor.h | 1 + arch/powerpc/include/asm/reg.h | 4 + arch/powerpc/kernel/asm-offsets.c | 6 + arch/powerpc/kernel/cpu_setup_power.S | 4 + arch/powerpc/kernel/exceptions-64s.S | 30 ++- arch/powerpc/kernel/idle_power7.S | 332 +++++++++++++++++++++---- arch/powerpc/platforms/powernv/opal-wrappers.S | 39 +++ arch/powerpc/platforms/powernv/powernv.h | 2 + arch/powerpc/platforms/powernv/setup.c | 160 ++++++++++++ arch/powerpc/platforms/powernv/smp.c | 10 +- arch/powerpc/platforms/powernv/subcore.c | 34 +++ arch/powerpc/platforms/powernv/subcore.h | 1 + drivers/cpuidle/cpuidle-powernv.c | 10 +- 17 files changed, 608 insertions(+), 60 deletions(-) create mode 100644 arch/powerpc/include/asm/cpuidle.h -- 1.9.3