From: <Alex_Gagniuc@Dellteam.com>
To: <helgaas@kernel.org>, <mr.nuke.me@gmail.com>
Cc: <Austin.Bolen@dell.com>, <keith.busch@intel.com>,
<Shyam.Iyer@dell.com>, <lukas@wunner.de>,
<mika.westerberg@linux.intel.com>, <okaya@codeaurora.org>,
<rafael.j.wysocki@intel.com>, <poza@codeaurora.org>,
<linux-pci@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] PCI: pciehp: Report degraded links via link bandwidth notification
Date: Thu, 29 Nov 2018 18:57:37 +0000 [thread overview]
Message-ID: <1828edee07fa483d9600aeb5b9b69456@ausx13mps321.AMER.DELL.COM> (raw)
In-Reply-To: <20181129173553.GD178809@google.com>
On 11/29/2018 11:36 AM, Bjorn Helgaas wrote:
> On Wed, Nov 28, 2018 at 06:08:24PM -0600, Alexandru Gagniuc wrote:
>> A warning is generated when a PCIe device is probed with a degraded
>> link, but there was no similar mechanism to warn when the link becomes
>> degraded after probing. The Link Bandwidth Notification provides this
>> mechanism.
>>
>> Use the link bandwidth notification interrupt to detect bandwidth
>> changes, and rescan the bandwidth, looking for the weakest point. This
>> is the same logic used in probe().
>
> I like the concept of this. What I don't like is the fact that it's
> tied to pciehp, since I don't think the concept of Link Bandwidth
> Notification is related to hotplug. So I think we'll only notice this
> for ports that support hotplug. Maybe it's worth doing it this way
> anyway, even if it could be generalized in the future?
That makes sense. At first, I thought that BW notification was tied to
hotplug, but our PCIe spec writer disagreed with that assertion. I'm
just not sure where to handle the interrupt otherwise.
Alex
next prev parent reply other threads:[~2018-11-29 18:57 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-29 0:08 Alexandru Gagniuc
2018-11-29 16:06 ` Mika Westerberg
2018-11-29 19:00 ` Alex_Gagniuc
2018-11-29 19:30 ` Mika Westerberg
2018-11-29 17:35 ` Bjorn Helgaas
2018-11-29 18:57 ` Alex_Gagniuc [this message]
2018-11-29 19:13 ` Lukas Wunner
2018-11-29 23:04 ` Bjorn Helgaas
2018-11-29 23:24 ` Alex_Gagniuc
2018-12-07 18:20 ` [PATCH v2] " Alexandru Gagniuc
2018-12-27 19:33 ` Alex G.
2019-02-25 2:28 ` Lukas Wunner
2019-02-27 20:21 ` Alex_Gagniuc
2019-02-28 6:43 ` Lukas Wunner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1828edee07fa483d9600aeb5b9b69456@ausx13mps321.AMER.DELL.COM \
--to=alex_gagniuc@dellteam.com \
--cc=Austin.Bolen@dell.com \
--cc=Shyam.Iyer@dell.com \
--cc=helgaas@kernel.org \
--cc=keith.busch@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=lukas@wunner.de \
--cc=mika.westerberg@linux.intel.com \
--cc=mr.nuke.me@gmail.com \
--cc=okaya@codeaurora.org \
--cc=poza@codeaurora.org \
--cc=rafael.j.wysocki@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome