From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756609AbbEUQdJ (ORCPT ); Thu, 21 May 2015 12:33:09 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:59230 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbbEUQdG (ORCPT ); Thu, 21 May 2015 12:33:06 -0400 Message-ID: <555E08BD.9010603@codeaurora.org> Date: Thu, 21 May 2015 11:33:01 -0500 From: Timur Tabi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Fu Wei , Guenter Roeck CC: 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 Subject: Re: [PATCH v2 6/7] Watchdog: introduce ARM SBSA watchdog driver 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> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Timur Tabi Subject: Re: [PATCH v2 6/7] Watchdog: introduce ARM SBSA watchdog driver Date: Thu, 21 May 2015 11:33:01 -0500 Message-ID: <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> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-watchdog-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Fu Wei , Guenter Roeck Cc: Suravee Suthikulpanit , Linaro ACPI Mailman List , linux-watchdog-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Wei Fu , G Gregory , Al Stone , Hanjun Guo , Ashwin Chaugule , Arnd Bergmann , vgandhi-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, wim-IQzOog9fTRqzQB+pC5nmwQ@public.gmane.org, Jon Masters , Leo Duran , Jon Corbet , Mark Rutland List-Id: devicetree@vger.kernel.org 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. -- Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html