From patchwork Wed Apr 6 15:39:07 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 8763511 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3CE3CC0553 for ; Wed, 6 Apr 2016 15:41:41 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6983F201EC for ; Wed, 6 Apr 2016 15:41:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A3A06201D3 for ; Wed, 6 Apr 2016 15:41:38 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1anpYi-0004Qk-54; Wed, 06 Apr 2016 15:39:56 +0000 Received: from linutronix.de ([2001:470:1f0b:db:abcd:42:0:1] helo=Galois.linutronix.de) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1anpYe-0004KK-7q for linux-arm-kernel@lists.infradead.org; Wed, 06 Apr 2016 15:39:53 +0000 Received: from localhost ([127.0.0.1] helo=bazinga.breakpoint.cc) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1anpYG-00009D-RW; Wed, 06 Apr 2016 17:39:28 +0200 From: Sebastian Andrzej Siewior To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] ARM: imx: always use TWD on IMX6Q Date: Wed, 6 Apr 2016 17:39:07 +0200 Message-Id: <1459957147-10133-1-git-send-email-bigeasy@linutronix.de> X-Mailer: git-send-email 2.8.0.rc3 X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160406_083952_466679_BE5FC8B1 X-CRM114-Status: GOOD ( 13.37 ) X-Spam-Score: -5.2 (-----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sebastian Andrzej Siewior , Shawn Guo , Sascha Hauer MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-5.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 --- 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 8ceda2844c4f..08bcf8fb76f2 100644 --- a/arch/arm/mach-imx/Kconfig +++ b/arch/arm/mach-imx/Kconfig @@ -524,7 +524,7 @@ 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