Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751723AbaAXJUA (ORCPT ); Fri, 24 Jan 2014 04:20:00 -0500 Received: from mail-pb0-f53.google.com ([209.85.160.53]:59466 "EHLO mail-pb0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750969AbaAXJT5 (ORCPT ); Fri, 24 Jan 2014 04:19:57 -0500 Message-ID: <52E2302D.5040001@linaro.org> Date: Fri, 24 Jan 2014 17:19:41 +0800 From: Hanjun Guo User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: Arnd Bergmann CC: Mark Rutland , "Rafael J. Wysocki" , Catalin Marinas , Will Deacon , Russell King - ARM Linux , "linux-acpi@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "grant.likely@linaro.org" , Matthew Garrett , Olof Johansson , Linus Walleij , Bjorn Helgaas , Rob Herring , "patches@linaro.org" , "linux-kernel@vger.kernel.org" , "linaro-kernel@lists.linaro.org" , "linaro-acpi@lists.linaro.org" , Charles Garcia-Tobin , Amit Daniel Kachhap Subject: Re: [PATCH 18/20] clocksource / acpi: Add macro CLOCKSOURCE_ACPI_DECLARE References: <1389961514-13562-1-git-send-email-hanjun.guo@linaro.org> <52DCE790.6080809@linaro.org> <20140122114616.GB15591@e106331-lin.cambridge.arm.com> <3140612.0s75qS6VKb@wuerfel> In-Reply-To: <3140612.0s75qS6VKb@wuerfel> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014年01月22日 22:56, Arnd Bergmann wrote: > On Wednesday 22 January 2014 11:46:16 Mark Rutland wrote: >> On Mon, Jan 20, 2014 at 09:08:32AM +0000, Hanjun Guo wrote: >>> On 2014-1-17 22:21, Arnd Bergmann wrote: >>>> On Friday 17 January 2014, Hanjun Guo wrote: >>>>> From: Amit Daniel Kachhap >>>>> >>>>> This macro does the same job as CLOCKSOURCE_OF_DECLARE. The device >>>>> name from the ACPI timer table is matched with all the registered >>>>> timer controllers and matching initialisation routine is invoked. >>>> I wouldn't anticipate this infrastructure to be required. Shouldn't all >>>> ARMv8 machines have an architected timer? >>> I not sure of this, could anyone can give some guidance? if only arch >>> timer is available for ARM64, this will make thing very simple. >> All ARMv8 systems should have an architected timer. >> >> However, they may also have other timers (e.g. global timers for use >> when CPUs are in low power states and their local architected timers >> aren't active). > But all other timers could be regular platform drivers I suppose. No > need for special infrastructure for those. One more information, acpi_early_init() is run before timekeeping_init() now, and that patch was merged into 3.14-rc1. So we can initialize timers for scanning the DSDT table, and it also means that timer defined in DSDT can be initialized early enough. Thanks Hanjun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/