From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755238AbcGLO3f (ORCPT ); Tue, 12 Jul 2016 10:29:35 -0400 Received: from mail.kernel.org ([198.145.29.136]:52486 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755071AbcGLO3Y (ORCPT ); Tue, 12 Jul 2016 10:29:24 -0400 Message-Id: <20160712142919.647214235@goodmis.org> User-Agent: quilt/0.61-1 Date: Tue, 12 Jul 2016 10:29:13 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-rt-users Cc: Thomas Gleixner , Carsten Emde , Sebastian Andrzej Siewior , John Kacur , Paul Gortmaker Subject: [PATCH RT 06/15] ARM: imx: always use TWD on IMX6Q References: <20160712142907.636678217@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=0006-ARM-imx-always-use-TWD-on-IMX6Q.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.18.36-rt38-rc1 stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior There is no reason to limit the TWD to be used on SMP kernels only if the hardware has it available. On Wandboard i.MX6SOLO, running PREEMPT-RT and cyclictest I see as max immediately after start in idle: UP : ~90us SMP: ~50us UP + TWD: ~20us. Based on this numbers I prefer the TWD over the slightly slower MXC timer. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Steven Rostedt --- arch/arm/mach-imx/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig index 11b2957f792b..41792b506b2e 100644 --- a/arch/arm/mach-imx/Kconfig +++ b/arch/arm/mach-imx/Kconfig @@ -605,7 +605,7 @@ config SOC_IMX6Q bool "i.MX6 Quad/DualLite support" select ARM_ERRATA_764369 if SMP select HAVE_ARM_SCU if SMP - select HAVE_ARM_TWD if SMP + select HAVE_ARM_TWD select PCI_DOMAINS if PCI select PINCTRL_IMX6Q select SOC_IMX6 -- 2.8.1