From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758020AbbEWR0K (ORCPT ); Sat, 23 May 2015 13:26:10 -0400 Received: from mail-ob0-f175.google.com ([209.85.214.175]:35786 "EHLO mail-ob0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757991AbbEWR0H (ORCPT ); Sat, 23 May 2015 13:26:07 -0400 MIME-Version: 1.0 In-Reply-To: <556097D5.9050103@codeaurora.org> References: <=fu.wei@linaro.org> <1432197156-16947-7-git-send-email-fu.wei@linaro.org> <555F4236.7040206@linaro.org> <4095167.UOriXdSu53@wuerfel> <556097D5.9050103@codeaurora.org> Date: Sun, 24 May 2015 01:26:06 +0800 Message-ID: Subject: Re: [PATCH v2 6/7] Watchdog: introduce ARM SBSA watchdog driver From: Fu Wei To: Timur Tabi Cc: Arnd Bergmann , Hanjun Guo , 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 , Ashwin Chaugule , Guenter Roeck , 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 Hi Timur, On 23 May 2015 at 23:08, Timur Tabi wrote: > Arnd Bergmann wrote: >> >> I think it's a reasonable assumption that someone will sooner or later >> put that hardware into an ARM32 machine, > > > I'm going to have to disagree. If they haven't done it by now, I can't > imagine any ARM SOC vendor creating a 32-bit ARM SOC with an SBSA watchdog > in it. I can imagine a vendor trying to repurpose an existing 32-bit ARM > SOC for the server market, but that SOC won't have an SBSA watchdog in it. I will agree with you on this, ONLY IF a people can represent ARM and all chip vendors say publicly: " We never ever use SBSA watchdog IP core on ARM32!" or " SBSA watchdog IP core is imcompatible with ARM32" Although the SBSA is all about ARMv8, but in "5 APPENDIX A: GENERIC WATCHDOG", it doesn't say "this is only for ARMv8". and its clock source "system counter" and arm_arch_timer have been in ARM32 Soc for years, and all the regs in SBSA watchdog is 32bit. I can't see why we can not do that, unless I miss something. I wonder why you are so sure "that SOC won't have an SBSA watchdog in it." any documentation ? Sorry, I am not a chip design engineer, I can't see why 32-bit ARM won't have an SBSA watchdog in it. > >> or run a 32-bit kernel on >> >> a chip that has it. > > > That might happen, but I would be very surprised, and I would need to be > convinced that it's useful. > > -- > 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