From mboxrd@z Thu Jan 1 00:00:00 1970 From: timur@codeaurora.org (Timur Tabi) Date: Wed, 3 Feb 2016 12:08:59 -0600 Subject: [PATCH v10 5/5] Watchdog: ARM SBSA Generic Watchdog half timeout panic support In-Reply-To: References: <1454519923-25230-1-git-send-email-fu.wei@linaro.org> <1454519923-25230-6-git-send-email-fu.wei@linaro.org> <56B23883.7000501@codeaurora.org> <56B23E99.1030604@codeaurora.org> Message-ID: <56B2423B.1020109@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Fu Wei wrote: > Actually I am taking your suggestion to avoid touching WCV in > interrupt routine. > So even we have pre-timeout support , it is useless for this > panic-on-half-timeout feature, > because pre-timeout == timeout / 2 (always). > > So maybe I misunderstand your suggestion, > could you let me know : why we want pre-timeout here? Maybe I'm confused. For pre-timeout, I think the SBSA watchdog driver should support only half-timeout. That is, the user cannot configure the length of the pre-timeout with this driver. He can only enable it, and it is automatically set to 1/2 timeout. So when pre-timeout occurs, the interrupt handler calls panic() or whatever it's supposed to do. So "pre-timeout == timeout / 2 (always)" is exactly what we want.