[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <201204182152.51421.rjw@sisk.pl>
Date: Wed, 18 Apr 2012 21:52:51 +0200
From: "Rafael J. Wysocki" <rjw@...k.pl>
To: huang ying <huang.ying.caritas@...il.com>
Cc: "Yan, Zheng" <zheng.z.yan@...el.com>, bhelgaas@...gle.com,
linux-kernel@...r.kernel.org, linux-pci@...r.kernel.org,
linux-pm@...r.kernel.org, Lin Ming <ming.m.lin@...el.com>,
Zhang Rui <rui.zhang@...el.com>,
ACPI Devel Mailing List <linux-acpi@...r.kernel.org>
Subject: Re: [RFC PATCH] PCIe: Add PCIe runtime D3cold support
On Wednesday, April 18, 2012, huang ying wrote:
> On Wed, Apr 18, 2012 at 4:43 AM, Rafael J. Wysocki <rjw@...k.pl> wrote:
> > On Tuesday, April 17, 2012, huang ying wrote:
> >> On Tue, Apr 17, 2012 at 10:12 AM, Yan, Zheng <zheng.z.yan@...el.com> wrote:
> >> > On 04/17/2012 01:07 AM, Rafael J. Wysocki wrote:
> >> >
> >> >> BTW, can you please explain to me what the #WAKE signal is and how it is
> >> >> different from PME#?
> >> >
> >> > #WAKE signal is triggered by a pin connected to the root complex or other
> >> > motherboard logic. PME# is triggered by PME message sent to the port.
> >>
> >> PME# is a PCI pin, while WAKE# is a PCI Express pin. In PCI Express,
> >> there is no PME#, PME is delivered between end point device and root
> >> port or root complex event collector via PME message, and the PME
> >> message will trigger IRQ on root port or root complex event collector.
> >> WAKE# is not used for PCI Express D1, D2 and D3hot, it is just used
> >> by D3cold. When remote wakeup detected by end point device, it will
> >> assert WAKE# to notify power controller (implemented via ACPI on some
> >> platform), then power controller will turn on power for main link,
> >> after link goes back to L0, PME message will be sent to root port or
> >> root complex event collector by end point device.
> >
> > OK
> >
> > So do I understand correctly that the WAKE# signal here is the one described
> > in Section 5.3.3.2 Link Wakeup of PCI Express Base spec. 2.0?
> >
> > So what happens is that it triggers a GPE and that GPE has a _Lxx method
> > associated with it, I suppose. Is that correct?
>
> Yes.
So I wonder what that _Lxx method looks like.
Thanks,
Rafael
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists