From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Authentication-Results: lists.ozlabs.org; spf=none (mailfrom) smtp.mailfrom=linux.intel.com (client-ip=192.55.52.151; helo=mga17.intel.com; envelope-from=haiyue.wang@linux.intel.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.intel.com Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 41C5Ww0PbSzF0kx for ; Sat, 23 Jun 2018 03:43:23 +1000 (AEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Jun 2018 10:43:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,258,1526367600"; d="scan'208";a="59425774" Received: from haiyuewa-mobl1.ccr.corp.intel.com (HELO [10.249.173.233]) ([10.249.173.233]) by FMSMGA003.fm.intel.com with ESMTP; 22 Jun 2018 10:43:17 -0700 Subject: Re: [PATCH ] ipmi: kcs_bmc: fix IRQ exception if the channel is not open To: minyard@acm.org, arnd@arndb.de, gregkh@linuxfoundation.org, openipmi-developer@lists.sourceforge.net, linux-kernel@vger.kernel.org Cc: luis.a.silva@dell.com, avi.fishman@nuvoton.com, openbmc@lists.ozlabs.org References: <1529636218-280096-1-git-send-email-haiyue.wang@linux.intel.com> <980bbe06-afa6-67b0-a3d3-c5fd921dcfbd@linux.intel.com> From: "Wang, Haiyue" Message-ID: <3950b9ff-79d6-b0f8-91fb-1a13b34c24d2@linux.intel.com> Date: Sat, 23 Jun 2018 01:43:16 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <980bbe06-afa6-67b0-a3d3-c5fd921dcfbd@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Mailman-Approved-At: Mon, 25 Jun 2018 09:18:43 +1000 X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Jun 2018 17:43:24 -0000 On 2018-06-23 01:23, Wang, Haiyue wrote: >> Maybe it's best to have the interrupt disabled unless the device is >> open. >> You have to handle the interrupt disable race on a close, but with the >> sync functions that shouldn't be too hard. >> > In fact, in BMC chip design, the LPC controller has many devices, such as > Port 80 snoop, BT, KCS etc, they shares the same interrupt. :) BTW, for AST2500, if the BMC and PCH run under eSPI (like LPC) mode, and if we disable the KCS devices, then reboot the BMC, it will cause the system hang, and the KCS channel can't be used anymore. So we need always enable these used KCS devices (keep the KCS enable register setting) for working well under eSPI mode.