From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <keith.busch@intel.com>
Cc: Takao Indoh <indou.takao@fujitsu.com>,
Takao Indoh <indou.takao@jp.fujitsu.com>,
axboe@fb.com, hch@lst.de, sagi@grimberg.me,
linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] nvme: Enable acceleration feature of A64FX processor
Date: Tue, 5 Feb 2019 17:13:47 +0100 [thread overview]
Message-ID: <20190205161347.GA847@lst.de> (raw)
In-Reply-To: <20190205143905.GG22199@localhost.localdomain>
On Tue, Feb 05, 2019 at 07:39:06AM -0700, Keith Busch wrote:
> > Standard PCIe devices can use Relaxed Ordering (RO) by setting Attr
> > field in the TLP header, however, this mechanism cannot be utilized if
> > the device does not support RO feature. Fujitsu A64FX processor has an
> > alternate feature to enable RO in its Root Port by setting the bit 56 of
> > DMA address. This mechanism enables to utilize RO feature even if the
> > device does not support standard PCIe RO.
>
> I think you're better of just purchasing devices that support the
> capability per spec rather than with a non-standard work around.
Agreed, this seems like a pretty gross hack.
next prev parent reply other threads:[~2019-02-05 16:13 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-01 12:46 [PATCH] nvme: Enable acceleration feature of A64FX processor Takao Indoh
2019-02-01 14:54 ` Keith Busch
2019-02-05 12:56 ` Takao Indoh
2019-02-05 14:39 ` Keith Busch
2019-02-05 16:13 ` Christoph Hellwig [this message]
2019-02-13 12:03 ` Takao Indoh
2019-02-14 17:11 ` Christoph Hellwig
2019-02-14 20:44 ` Elliott, Robert (Persistent Memory)
2019-02-14 21:17 ` Keith Busch
2019-02-20 9:46 ` Takao Indoh
2019-02-22 17:07 ` Keith Busch
2019-02-01 15:51 ` Christoph Hellwig
2019-02-05 12:56 ` Takao Indoh
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=20190205161347.GA847@lst.de \
--to=hch@lst.de \
--cc=axboe@fb.com \
--cc=indou.takao@fujitsu.com \
--cc=indou.takao@jp.fujitsu.com \
--cc=keith.busch@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=sagi@grimberg.me \
/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).