From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965042AbbFJOhC (ORCPT ); Wed, 10 Jun 2015 10:37:02 -0400 Received: from mail-ob0-f176.google.com ([209.85.214.176]:34602 "EHLO mail-ob0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933354AbbFJOgw (ORCPT ); Wed, 10 Jun 2015 10:36:52 -0400 MIME-Version: 1.0 In-Reply-To: <5578482E.70307@codeaurora.org> References: <=fu.wei@linaro.org> <1433217907-928-1-git-send-email-fu.wei@linaro.org> <1433217907-928-6-git-send-email-fu.wei@linaro.org> <556DCC95.806@codeaurora.org> <556DE2D5.3090906@roeck-us.net> <5575DE48.8010308@roeck-us.net> <55766D74.2060401@roeck-us.net> <55769E0E.8060801@roeck-us.net> <557712CF.8010802@roeck-us.net> <5577147B.2030900@codeaurora.org> <5577180E.4070804@roeck-us.net> <5578482E.70307@codeaurora.org> Date: Wed, 10 Jun 2015 22:36:51 +0800 Message-ID: Subject: Re: [PATCH v4 5/7] 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 , Catalin Marinas , Will Deacon , rjw@rjwysocki.net Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10 June 2015 at 22:22, Timur Tabi wrote: > Fu Wei wrote: >> >> Another weakness of only using WOR is the timeout limited by this >> 32bit register. >> 10s @400MHz generic Timer >> >> I don't think this limit is good for a server, once the server is in a >> heavy load > > > Perhaps, but if that's the limitation of the hardware, then so be it. it is not the real limitation, if we use WCV, SBSA spec has mentioned that. ------ SBSA 2.3-------Page 23 ---------- Note: the watchdog offset register is 32 bits wide. This gives a maximum watch period of around 10s at a system counter frequency of 400MHz. If a larger watch period is required then the compare value can be programmed directly into the compare value register ------ SBSA 2.3-------Page 23 ---------- if some hardware doesn't support writing WCV, that means this hardware is non-standard SBSA watchdog. > > -- > Sent by an employee of the Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the > Code Aurora Forum, hosted by The Linux Foundation. -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fu Wei Subject: Re: [PATCH v4 5/7] Watchdog: introduce ARM SBSA watchdog driver Date: Wed, 10 Jun 2015 22:36:51 +0800 Message-ID: References: <=fu.wei@linaro.org> <1433217907-928-1-git-send-email-fu.wei@linaro.org> <1433217907-928-6-git-send-email-fu.wei@linaro.org> <556DCC95.806@codeaurora.org> <556DE2D5.3090906@roeck-us.net> <5575DE48.8010308@roeck-us.net> <55766D74.2060401@roeck-us.net> <55769E0E.8060801@roeck-us.net> <557712CF.8010802@roeck-us.net> <5577147B.2030900@codeaurora.org> <5577180E.4070804@roeck-us.net> <5578482E.70307@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: <5578482E.70307-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: linux-watchdog-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Timur Tabi Cc: Guenter Roeck , 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 , Catalin Marinas , Will Deacon , rjw-LthD3rsA81gm4RdzfppkhA@public.gmane.org List-Id: devicetree@vger.kernel.org On 10 June 2015 at 22:22, Timur Tabi wrote: > Fu Wei wrote: >> >> Another weakness of only using WOR is the timeout limited by this >> 32bit register. >> 10s @400MHz generic Timer >> >> I don't think this limit is good for a server, once the server is in a >> heavy load > > > Perhaps, but if that's the limitation of the hardware, then so be it. it is not the real limitation, if we use WCV, SBSA spec has mentioned that. ------ SBSA 2.3-------Page 23 ---------- Note: the watchdog offset register is 32 bits wide. This gives a maximum watch period of around 10s at a system counter frequency of 400MHz. If a larger watch period is required then the compare value can be programmed directly into the compare value register ------ SBSA 2.3-------Page 23 ---------- if some hardware doesn't support writing WCV, that means this hardware is non-standard SBSA watchdog. > > -- > Sent by an employee of the Qualcomm Innovation Center, Inc. > The Qualcomm Innovation Center, Inc. is a member of the > Code Aurora Forum, hosted by The Linux Foundation. -- 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-watchdog" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html