qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>,
	Anthony Liguori <anthony@codemonkey.ws>,
	Marcel Apfelbaum <marcel.a@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] hw/pci: completed master-abort emulation
Date: Tue, 24 Sep 2013 18:41:11 +0300	[thread overview]
Message-ID: <20130924154111.GA21888@redhat.com> (raw)
In-Reply-To: <CAFEAcA8NU9GhQ9Q2j2LYhnHjjE+KvMv9-vkTiyoVHiQUFW_yYQ@mail.gmail.com>

On Tue, Sep 24, 2013 at 08:21:50PM +0900, Peter Maydell wrote:
> On 24 September 2013 20:17, Marcel Apfelbaum <marcel.a@redhat.com> wrote:
> > I was suggesting an algorithm to find the MA device in order
> > to set MA Received Bit in its Status(Sec_Status) register.
> >
> > The algorithm was to traverse the PCI buses for finding the
> > MA device using the transaction address.
> 
> Yes. My point is that if you have an algorithm phrased as
> "dynamically traverse some hierarchy using an address
> to find something" then you can rephrase it as "statically
> construct a hierarchy of memory regions and then just
> query it with the address".
> 
> -- PMM

Right. You might be able to use MR hierarchy to find the last bridge to
claim transaction.  That should to be enough for PCI, for express you
then need to find all devices on the path between bus master and the
last bridge.  For this task, memory subsystem can't be used I think.

Whether the result will be cleaner than open-coding it all, I don't
really know.

-- 
MST

  parent reply	other threads:[~2013-09-24 15:39 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-23 11:01 [Qemu-devel] [PATCH] hw/pci: completed master-abort emulation Marcel Apfelbaum
2013-09-23 11:27 ` Michael S. Tsirkin
2013-09-23 12:37   ` Marcel Apfelbaum
2013-09-23 13:45     ` Michael S. Tsirkin
2013-09-23 14:43       ` Marcel Apfelbaum
2013-09-23 15:10         ` Michael S. Tsirkin
2013-09-23 17:49           ` Marcel Apfelbaum
2013-09-23 18:45             ` Michael S. Tsirkin
2013-09-24  8:07               ` Marcel Apfelbaum
2013-09-24  8:29                 ` Michael S. Tsirkin
2013-09-24  8:44                   ` Marcel Apfelbaum
2013-09-24  8:58                     ` Michael S. Tsirkin
2013-09-24 10:44                       ` Marcel Apfelbaum
2013-09-24 10:55                         ` Peter Maydell
2013-09-24 11:17                           ` Marcel Apfelbaum
2013-09-24 11:21                             ` Peter Maydell
2013-09-24 11:41                               ` Marcel Apfelbaum
2013-09-24 15:41                               ` Michael S. Tsirkin [this message]
2013-09-24 16:24                                 ` Michael S. Tsirkin
2013-09-24 23:36                                 ` Peter Maydell
2013-09-24 23:43                                   ` Michael S. Tsirkin

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=20130924154111.GA21888@redhat.com \
    --to=mst@redhat.com \
    --cc=anthony@codemonkey.ws \
    --cc=marcel.a@redhat.com \
    --cc=peter.maydell@linaro.org \
    --cc=qemu-devel@nongnu.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 NNTP newsgroup(s).