From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757949Ab3AIOqs (ORCPT ); Wed, 9 Jan 2013 09:46:48 -0500 Received: from service87.mimecast.com ([91.220.42.44]:42548 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756488Ab3AIOqr (ORCPT ); Wed, 9 Jan 2013 09:46:47 -0500 From: Mark Rutland To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, tglx@linutronix.de, nico@linaro.org, will.deacon@arm.com, marc.zyngier@arm.com, john.stultz@linaro.org, mark.rutland@arm.com Subject: [PATCHv2 0/4] clockevents: decouple broadcast mechanism from drivers Date: Wed, 9 Jan 2013 14:46:06 +0000 Message-Id: <1357742770-15028-1-git-send-email-mark.rutland@arm.com> X-Mailer: git-send-email 1.7.0.4 X-OriginalArrivalTime: 09 Jan 2013 14:46:42.0557 (UTC) FILETIME=[23ABF2D0:01CDEE78] X-MC-Unique: 113010914464509101 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 r09Eko6R006469 This is an updated version of the series I posted back in December: http://lists.infradead.org/pipermail/linux-arm-kernel/2012-December/137929.html Changes since v1: * Drop removal of guards in smp.c * Removed useless evt->evt_handler check in tick_receive_broadcast * Fix up tick_receive_broadcast when !GENERIC_CLOCKEVENTS_BROADCAST * Fix checkpatch issues (multi-line strings) Thanks go to Stephen Boyd and Santosh Shilimkar for their commments. In some SMP systems, cpu-local timers may stop delivering interrupts when in low power states, or not all CPUs may have local timers. To support these systems we have a mechanism for broadcasting timer ticks to other CPUs. This mechanism relies on the struct clock_event_device::broadcast function pointer, which is a driver-specific mechanism for broadcasting ticks to other CPUs. As the broadcast mechanism is architecture-specific, placing the broadcast function on struct clock_event_device ties each driver to a single architecture. Additionally the driver or architecture backend must handle the routing of broadcast ticks to the correct clock_event_device, leading to duplication of the list of active clock_event_devices. These patches introduce a generic mechanism for handling the receipt of timer broadcasts, and an optional architecture-specific broadcast function which allows drivers to be decoupled from a particular architecture will retaining support for timer tick broadcasts. These mechanisms are wired up for the arm port, and have been boot-tested on a pandaboard. Thanks, Mark. Mark Rutland (4): clockevents: Add generic timer broadcast receiver arm: Use generic timer broadcast receiver clockevents: Add generic timer broadcast function arm: Add generic timer broadcast support arch/arm/Kconfig | 1 + arch/arm/kernel/smp.c | 11 ++--------- include/linux/clockchips.h | 14 ++++++++++++++ kernel/time/Kconfig | 4 ++++ kernel/time/tick-broadcast.c | 25 +++++++++++++++++++++++++ 5 files changed, 46 insertions(+), 9 deletions(-)