From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751521AbbKBVtl (ORCPT ); Mon, 2 Nov 2015 16:49:41 -0500 Received: from mout.kundenserver.de ([212.227.126.130]:63352 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751023AbbKBVti (ORCPT ); Mon, 2 Nov 2015 16:49:38 -0500 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Cc: Daniel Lezcano , Jisheng Zhang , tglx@linutronix.de, linux-kernel@vger.kernel.org, Arnd Bergmann Subject: Re: [PATCH] clocksource: dw_apb_timer_of: support timer-based delay Date: Mon, 02 Nov 2015 22:49:01 +0100 Message-ID: <4138087.gESYTxjr8X@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: <56372366.6090905@linaro.org> References: <1446193659-1698-1-git-send-email-jszhang@marvell.com> <20151102105113.72aade85@xhacker> <56372366.6090905@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:k5bNv5ZMkHq9rQ/UCsfHMyEW2CQf9ssrMs7/LQBxry5zeXioVMr OdlV6ozcQ824zlAwRlM8QNSjlp7onjjXftL2Y8VZisy/cG2WKXBW5/7vO9qQX4i/X8jvXLv 3JdEOok6v+koXDNYRXJb/x/9M/Hbv2bha9jh9xZSUJ97H7yCGQRkwSpSnAW8pXBnkNycTY1 NzK+4C65RHKLeEsPglXsw== X-UI-Out-Filterresults: notjunk:1;V01:K0:wXiu+8dSPAY=:Gj5bllK4E99qALzxDIWYnc 0z/pt+bXJd1I7b8a4qlM2RLV7ahgd2Czc41HuAMei+oviuQZJuIgrJClGpNi8uAgYdIkz0FN+ Xyus+GckX2QQBWUtnHGpRVFo5InkczSFpMg1suAqlqsXNRv7XFh4znANjUlIFkiZWVj+0N7NV x2330/jwSzupq+6VCH6qXH1832JoB1SDK/AZLvEiqz6VUxLGHrh38CxGTrlNPROJRozLHpLkA gVnGWQq+RG+CrtD6UAIDEp+cD9z1E9SVXSbw5FCjwDS7qxyJkv5LdPvUORcouZM9jFan15ikH CDKuxrhUT9MHSqqJ9KqLIiicIsvENGDJL/O+qUo/mHmPptJRqJbGVmQ/HWHsWEhWJKBfK7rwG Mi2W8vblO/5ePk3lgcNhLaf6tycmGhQKH3WygtjHZ8g90q6CME/Htji1vABy+/XbKU3a1jFbn qpiVyY6fmGse0CepPFpW20NsyTlZ5Vbhg6KvHdZQYmwAGiiC4B8QRbqkU3YJjIh0iZJ7ZhWRM 4eetS3+JvXSkMPcIHUYQl7HXuraxLxkAl7jQ3sxNUrPs5ZC8JjOdZUQ/+6fzzXFYjxsaw14wj OjDSuzTzcDn2D7oXqF63/qkTVQcsDupEAj5uMkDy4CFIjmByUj8V0f23yErXsRayKsx6WAGM6 3ofeDyHyyzquOQ5jECBmk24xYNuFm7aLezmXTQM6VbsKSF6SdU99OTbbvXVk9jdj3ns9CTVww Hc+vaD6kfYOr1lvm Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday 02 November 2015 09:48:38 Daniel Lezcano wrote: > If I follow the logic of arch_arm_timer is better than dw_apb timer. > > 1. The arch_arm_timer is present > > => dw_apb timer is not used at all > > CONFIG_ARM_ARCH_TIMER=y > # CONFIG_DW_APB_TIMER is not set > > 2. The arch_arm_timer is *not* present > > => dw_apb_timer is used with delay code > > # CONFIG_ARM_ARCH_TIMER is not set > CONFIG_DW_APB_TIMER=y > > In both cases, DW_APB_TIMER_BASED_DELAY is not needed. > This still has the same problem that running a multi_v7_defconfig kernel or a binary distro kernel will always enable both. We really want to have a good run-time decision, not compile-time. Arnd