From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 3ysTDx6xcJzDsLw for ; Thu, 7 Dec 2017 06:28:49 +1100 (AEDT) Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id vB6JSDfV001374 for ; Wed, 6 Dec 2017 14:28:46 -0500 Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) by mx0a-001b2d01.pphosted.com with ESMTP id 2epm1wfkvu-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 06 Dec 2017 14:28:46 -0500 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 6 Dec 2017 14:28:44 -0500 Subject: Re: [PATCH v2] powerpc/powernv: Add pci_reset_phbs parameter to issue a PHB reset To: Balbir Singh Cc: Paul Mackerras , "open list:LINUX FOR POWERPC (32-BIT AND 64-BIT)" References: <20171025152754.25166-1-gpiccoli@linux.vnet.ibm.com> <95c483cf-93dc-6b99-f406-cb59d3263442@linux.vnet.ibm.com> From: "Guilherme G. Piccoli" Date: Wed, 6 Dec 2017 17:28:39 -0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Message-Id: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 11/21/2017 12:35 AM, Balbir Singh wrote: > On Thu, Nov 16, 2017 at 11:14 PM, Guilherme G. Piccoli > wrote: >> On 11/16/2017 01:49 AM, Balbir Singh wrote: >>> On Thu, Oct 26, 2017 at 2:27 AM, Guilherme G. Piccoli >>> wrote: >>>> During a kdump kernel boot in PowerPC, we request a reset of the PHBs >>>> to the FW. It makes sense, since if we are booting a kdump kernel it >>>> means we had some trouble before and we cannot rely in the adapters' >>>> health; they could be in a bad state, hence the reset is needed. >>>> >>>> But this reset is useful not only in kdump - there are situations, >>>> specially when debugging drivers, that we could break an adapter in >>>> a way it requires such reset. One can tell to just go ahead and >>>> reboot the machine, but happens that many times doing kexec is much >>>> faster, and so preferable than a full power cycle. >>>> >>>> This patch adds the pci_reset_phbs parameter to perform such reset >>>> when desired by the user. >>>> >>> >>> Do we care to reset specific phbs or all of them? I guess all based on >>> your description. >> >> Exactly Balbir, it does reset all of them. We could add such >> granularity, but I don't see much usability.. >> But if somebody feels it's useful, we can change... >> > > OK.. makes sense, any reason why this can't be folded into reset_devices? > I guess we want reset_phbs to be independent of reset_devices It was, in v1. But mpe asked it to be a powerpc specific parameter heheh Cheers, Guilherme > > Balbir >