Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755977AbbEVFFr (ORCPT ); Fri, 22 May 2015 01:05:47 -0400 Received: from mail-ob0-f173.google.com ([209.85.214.173]:35437 "EHLO mail-ob0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062AbbEVFFk (ORCPT ); Fri, 22 May 2015 01:05:40 -0400 MIME-Version: 1.0 In-Reply-To: <555E08BD.9010603@codeaurora.org> References: <=fu.wei@linaro.org> <1432197156-16947-1-git-send-email-fu.wei@linaro.org> <1432197156-16947-7-git-send-email-fu.wei@linaro.org> <555DB4C4.5090606@roeck-us.net> <20150521151847.GA16668@roeck-us.net> <20150521155950.GA18300@roeck-us.net> <555E08BD.9010603@codeaurora.org> Date: Fri, 22 May 2015 13:05:38 +0800 Message-ID: Subject: Re: [PATCH v2 6/7] Watchdog: introduce ARM SBSA watchdog driver From: Fu Wei To: Timur Tabi Cc: Guenter Roeck , Suravee Suthikulpanit , Linaro ACPI Mailman List , linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Wei Fu , G Gregory , Al Stone , Hanjun Guo , Ashwin Chaugule , Arnd Bergmann , vgandhi@codeaurora.org, wim@iguana.be, Jon Masters , Leo Duran , Jon Corbet , Mark Rutland Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1997 Lines: 56 Hi Timur. On 22 May 2015 at 00:33, Timur Tabi wrote: > On 05/21/2015 11:12 AM, Fu Wei wrote: >>> >>> > >>> >Having said that, my personal preference would be for the counter >>> >and rate to be exported through the clock subsystem (ie with >>> >clk_get_rate). But that would still not provide the current counter >>> >value, so maybe that isn't even possible. >> >> I will try to make a patch for this, If the arm maintainers don't like >> exporting "arch_timer_get_rate();" >> >> But your thought is good, the clk_get_rate is the best way to do for now > > > The rate isn't the problem. It's the current timestamp counter. The only > way to get that is with either arch_counter_get_cntvct() or > arch_timer_read_counter(). I'm not sure which of the two functions is > better. However, arch_timer_read_counter() is really just a function > pointer that points to arch_counter_get_cntvct(). > > Also, clk_get_rate() only works if you have a real clk object. I've said > this before many times, but on my ACPI platform, there are no clk objects. > Clocks are handled by UEFI. Thanks for your info, I think : right now , do what we can do, export the interface of arch_timer, If the arm maintainers don't like this way, we can find another way later or find a option as plan B. > > -- > Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the > Code Aurora Forum, a Linux Foundation Collaborative Project. -- Best regards, Fu Wei Software Engineer Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch Ph: +86 21 61221326(direct) Ph: +86 186 2020 4684 (mobile) Room 1512, Regus One Corporate Avenue,Level 15, One Corporate Avenue,222 Hubin Road,Huangpu District, Shanghai,China 200021 -- 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/