linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alex Williamson <alex.williamson@redhat.com>
To: Vikas Gupta <vikas.gupta@broadcom.com>
Cc: Cornelia Huck <cohuck@redhat.com>,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	Vikram Prakash <vikram.prakash@broadcom.com>,
	Srinath Mannam <srinath.mannam@broadcom.com>,
	Auger Eric <eric.auger@redhat.com>
Subject: Re: MSI/MSIX for VFIO platform
Date: Thu, 10 Sep 2020 10:57:35 -0600	[thread overview]
Message-ID: <20200910105735.1e060b95@w520.home> (raw)
In-Reply-To: <c94c36305980f80674aa699e27b9895b@mail.gmail.com>

On Thu, 10 Sep 2020 16:15:27 +0530
Vikas Gupta <vikas.gupta@broadcom.com> wrote:

> Hi Alex/Cornelia,
> 
> We are looking for MSI interrupts for platform devices in user-space
> applications via event/poll mechanism using VFIO.
> 
> Since there is no support for MSI/MSIX handling in VFIO-platform in kernel,
> it may not possible to get this feature in user-space.
> 
> Is there any other way we can get this feature in user-space OR can you
> please suggest if any patch or feature is in progress for same in VFIO
> platform?
> 
> Any suggestions would be helpful.

Eric (Cc'd) is the maintainer of vfio-platform.

vfio-platform devices don't have IRQ indexes dedicated to MSI and MSI-X
like vfio-pci devices do (technically these are PCI concepts, but I
assume we're referring generically to message signaled interrupts), but
that's simply due to the lack of standardization in platform devices.
Logically these are simply collections of edge triggered interrupts,
which the vfio device API supports generically, it's simply a matter
that the vfio bus driver exposing a vfio-platform device create an IRQ
index exposing these vectors.  Thanks,

Alex


       reply	other threads:[~2020-09-10 17:02 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <c94c36305980f80674aa699e27b9895b@mail.gmail.com>
2020-09-10 16:57 ` Alex Williamson [this message]
2020-09-11 13:52   ` MSI/MSIX for VFIO platform Auger Eric
2020-09-14  7:06     ` Vikas Gupta

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=20200910105735.1e060b95@w520.home \
    --to=alex.williamson@redhat.com \
    --cc=cohuck@redhat.com \
    --cc=eric.auger@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=srinath.mannam@broadcom.com \
    --cc=vikas.gupta@broadcom.com \
    --cc=vikram.prakash@broadcom.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;
as well as URLs for NNTP newsgroup(s).