From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E4CAF39FC5; Thu, 5 Sep 2024 15:56:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725551793; cv=none; b=IqIav5pWa7uXAcJfmcf2newbCM3pP3T54nLrbpeuDk87CEXnyOenJx0oGCHudUpuMrhnwc/Gh0ku0RwynzoEfynaRqqvxRl2WSDNQyM+hk0gjofRJmrekHDedNDEjD4QmdbcKGKvURvah2uWocZnmNOXXCQJvqtEbi7MyUKViUU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725551793; c=relaxed/simple; bh=SbiTllZxgjb4Z1LIvyrQY8muQQ4twsbvg/wM/LIgpFA=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=LG8hQlUdjAT0wKD76bpEbXs5t3jEhh+UhoKtDye/hUJSN7aRO42L1Ak2mEAVoW4KWTz/r/PU+EP0CmHf3/XlQq6KJkSWynEgxHBijl899RIzTiSumlGvAy2iSN/O2+rdi/KZ+iebNtLNUC+Pdf1Vyw5O06xuCtXaLZsAEoHByLs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PGQUZ47q; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PGQUZ47q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3910CC4CEC3; Thu, 5 Sep 2024 15:56:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1725551791; bh=SbiTllZxgjb4Z1LIvyrQY8muQQ4twsbvg/wM/LIgpFA=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=PGQUZ47qOlkivM3ccuS+8SWeD5qbn9BbY+rd3e0/I8zh9E6QuDm97fyLOEntEp8v5 agrNCunp5cXCKs+3qJ/BJJHWNzieyJtIvqvVB2mkbrIjwb9WR9k4BA1uY3yvI0DtIQ d6CPoeY565B6eMnx8OPGQV7eoQRTjGs+7PI6Bm8g65QS9Hfj35yaLxB/bkFQNbRxo3 Hgh2e037JwEvcipMqA7efA0ZJqUHx9CxdisiZtbSsBh1Jk3ErfqCYLysYpq3nWo0yc HRwpfHAsSyMB8oXi8HLEyOqUcyEb7m9rpuPz34H629j7JWlhamoDe4HA+S8T9+nqpg bQTmWM8O7oSNA== Date: Thu, 5 Sep 2024 10:56:29 -0500 From: Bjorn Helgaas To: Mariusz Tkaczyk Cc: Tony Hutter , bhelgaas@google.com, minyard@acm.org, linux-pci@vger.kernel.org, openipmi-developer@lists.sourceforge.net, Linux Kernel Mailing List Subject: Re: [PATCH] PCI: Introduce Cray ClusterStor E1000 NVMe slot LED driver Message-ID: <20240905155629.GA389032@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240905081925.00001d14@linux.intel.com> On Thu, Sep 05, 2024 at 08:19:25AM +0200, Mariusz Tkaczyk wrote: > On Tue, 3 Sep 2024 17:18:20 -0500 > Bjorn Helgaas wrote: > > > On Tue, Aug 27, 2024 at 02:03:48PM -0700, Tony Hutter wrote: > > > Add driver to control the NVMe slot LEDs on the Cray ClusterStor E1000. > > > The driver provides hotplug attention status callbacks for the 24 NVMe > > > slots on the E1000. This allows users to access the E1000's locate and > > > fault LEDs via the normal /sys/bus/pci/slots//attention sysfs > > > entries. This driver uses IPMI to communicate with the E1000 controller to > > > toggle the LEDs. > > > > I hope/assume the interface is the same as one of the others, i.e., > > the existing one added for NVMe behind VMD by > > https://git.kernel.org/linus/576243b3f9ea ("PCI: pciehp: Allow > > exclusive userspace control of indicators") or the new one for NPEM > > and the _DSM at > > https://lore.kernel.org/linux-pci/20240814122900.13525-3-mariusz.tkaczyk@linux.intel.com/ > > > > I suppose we intend that the ledmon utility will be able to drive > > these LEDs? Whatever the user, we should try to minimize the number > > of different interfaces for this functionality. > > Ledmon won't support it, at least not in current form. Ledmon > support for pciehp attention is limited to VMD, i.e. first we must > find VMD driver then we are looking for slot/attention. I'm not > familiar with any attempt to add support for this in ledmon. > > From the end user perspective, I don't like pciehp/attention because > we are refereeing to pciehp driver not pcieport and to determine > proper slot we need to do additional matching by slot/address. I > would be simpler. > https://github.com/intel/ledmon/blob/main/src/lib/vmdssd.c#L100 All I'm trying to say is that NPEM, the related _DSM, and the VMD special case are all ways to control NVMe slot IDs. This Cray thing is another. We already have two user interfaces (the NPEM/_DSM one and the VMD one), and I'd like to avoid adding a third.