Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751388AbbEXRcl (ORCPT ); Sun, 24 May 2015 13:32:41 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:52403 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751116AbbEXRch (ORCPT ); Sun, 24 May 2015 13:32:37 -0400 Message-ID: <55620B2F.5000708@roeck-us.net> Date: Sun, 24 May 2015 10:32:31 -0700 From: Guenter Roeck User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Timur Tabi , Fu Wei 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> <555DFCD4.3040701@codeaurora.org> <5560D7AC.50009@codeaurora.org> <5560DCB6.3090008@roeck-us.net> <5561E7EA.5090702@codeaurora.org> <5561F8A8.4080607@codeaurora.org> <5561FC70.5080802@roeck-us.net> <5561FFF0.5090108@codeaurora.org> <55620808.4030605@codeaurora.org> In-Reply-To: <55620808.4030605@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: authenticated_id: linux@roeck-us.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1098 Lines: 31 On 05/24/2015 10:19 AM, Timur Tabi wrote: > Fu Wei wrote: >> I don't know why you want to do this tricky way. you can always >> register the interrupt handler, >> if pre-timeout is 0, system will just trigger WS1 right after WS0 > > But that only works if the pre-timeout and timeout can be programmed to separate values. And as Guenter says, the SBSA may not guarantee that. > The pseudo-code in the specification suggests that if WCV is configured, WS0 = WCV WS1 = WCV + WOR Assuming that the implementation follows the pseudo-code in the specification, we would have separately programmable values. Since the pretimeout (per ABI) is the difference in seconds to the timeout, and not an absolute value, we would have to program the registers as follows. WCV = timeout - pretimeout; WOR = pretimeout; Does this make sense ? Thanks, Guenter -- 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/