From: Rajat Jain <rajatjain@juniper.net>
To: "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
"linux-hotplug@vger.kernel.org" <linux-hotplug@vger.kernel.org>
Cc: Guenter Roeck <groeck@juniper.net>,
"kernelnewbies@kernelnewbies.org"
<kernelnewbies@kernelnewbies.org>,
"linux-newbie@vger.kernel.org" <linux-newbie@vger.kernel.org>
Subject: [PCIe spec question] How to get PCI express link up / link down notifications?
Date: Fri, 04 Oct 2013 01:40:49 +0000 [thread overview]
Message-ID: <1fa2fecbcbe147cc83a3011ff23e3d1a@BN1PR05MB123.namprd05.prod.outlook.com> (raw)
Hello,
I have a HW which is not compliant with the PCI Express hot-plug (as described in the PCI express spec) because the HP signals from the downstream port are simply not connected. And I have a PCI express endpoint, that in the course of its life, will routinely undergo power-off and power-on on cycles. Hence the PCIe link to this device is expected to come down, and come up as part of regular operation.
I'm reading the PCI express spec trying to understand if it is possible to get notification interrupts, whenever the PCIe link to this device goes down or goes up. Can someone please help me understand if it is possible?
In the link control register, I only see the capability to generate interrupts when "link bandwidth" changes and looking at the text, I doubt if Link down or link up counts as "link bandwidth change". Is there a way to generate and interrupt / notification when the Link goes up or down?
Thanks,
Rajat Jain
next reply other threads:[~2013-10-04 1:40 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-04 1:40 Rajat Jain [this message]
2013-10-04 2:36 ` [PCIe spec question] How to get PCI express link up / link down notifications? Greg KH
2013-10-04 3:31 ` Rajat Jain
2013-10-04 6:48 ` Rajat Jain
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=1fa2fecbcbe147cc83a3011ff23e3d1a@BN1PR05MB123.namprd05.prod.outlook.com \
--to=rajatjain@juniper.net \
--cc=groeck@juniper.net \
--cc=kernelnewbies@kernelnewbies.org \
--cc=linux-hotplug@vger.kernel.org \
--cc=linux-newbie@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
/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;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).