From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: Date: Fri, 22 Dec 2017 15:20:44 -0800 From: Brian Norris To: Tony Lindgren Subject: Re: [RFC PATCH v2 1/3] PCI: rockchip: Add support for pcie wake irq Message-ID: <20171222232043.GA158981@google.com> References: <20170817120431.12398-1-jeffy.chen@rock-chips.com> <20170817120431.12398-2-jeffy.chen@rock-chips.com> <20170818170107.GA119461@google.com> <20170818181416.GF6008@atomide.com> <5997486D.4040803@rock-chips.com> <20170822172653.GJ6008@atomide.com> <599CDB37.3070307@rock-chips.com> <20171219004811.GA216620@google.com> <20171220191912.GM3875@atomide.com> MIME-Version: 1.0 In-Reply-To: <20171220191912.GM3875@atomide.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Heiko Stuebner , linux-pci@vger.kernel.org, shawn.lin@rock-chips.com, jeffy , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, dianders@chromium.org, linux-rockchip@lists.infradead.org, bhelgaas@google.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+bjorn=helgaas.com@lists.infradead.org List-ID: + Rafael to this thread On Wed, Dec 20, 2017 at 11:19:12AM -0800, Tony Lindgren wrote: > * Brian Norris [171219 00:50]: > > On Wed, Aug 23, 2017 at 09:32:39AM +0800, Jeffy Chen wrote: > > > > Did this problem ever get resolved? To be clear, I believe the problem > > at hand is: > > > > (a) in suspend/resume (not runtime PM; we may not even have runtime PM > > support for most PCI devices) > > It seems it should be enough to implement runtime PM in the PCI > controller. Isn't each PCI WAKE# line is wired from each PCI device > to the PCI controller? No, not really. As discussed in later versions of this thread already, the WAKE# hierarchy is orthogonal to the PCI hierarchy, and I think we settled that it's reasonable to just consider this as a 1-per-device thing, with each device "directly" attached to the PM controller. While sharing could happen, that's something we decided to punt on...didn't we? > Then the PCI controller can figure out from which PCI device the > WAKE# came from. I'm not completely sure of the details, but I believe this *can* be determined by PME. But I'm not sure it's guaranteed to be supported, especially in cases where we already have 1:1 WAKE#. So we should be *trying* to report this wakeirq info from the device, if possible. > > Options I can think of: > > (1) implement runtime PM callbacks for all PCI devices, where we clear > > any PME status and ensure WAKE# stops asserting [1] > > I don't think this is needed, it should be enough to have just > the PCI controller implement runtime PM :) Brian _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel