public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Luis R. Rodriguez" <mcgrof@gmail.com>,
	Alan Cox <alan@lxorguk.ukuu.org.uk>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	Jeff Garzik <jeff@garzik.org>,
	"John W. Linville" <linville@tuxdriver.com>,
	linux-wireless <linux-wireless@vger.kernel.org>
Subject: Re: [PATCH] Clarify pci_iomap() usage for MMIO-only devices
Date: Wed, 19 Sep 2007 08:21:57 +1000	[thread overview]
Message-ID: <1190154117.6403.127.camel@localhost.localdomain> (raw)
In-Reply-To: <alpine.LFD.0.999.0709181323260.16478@woody.linux-foundation.org>

On Tue, 2007-09-18 at 13:30 -0700, Linus Torvalds wrote:
> Quite frankly, if performance is a _real_ reason to avoid 
> ioread*/iowrite*, I'll happily accept read*/write*, but it would be
> needed 
> to be backed up by real numbers. Can you even measure it?
> 

Also, I've been told that modern x86 chipsets have the ability to remap
IO space in the CPU physical address space. Is that true ? That would
allow even x86 to get rid of the condition and just use some magic
offset at map time.

Ben.



  parent reply	other threads:[~2007-09-18 22:22 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-17 20:22 [PATCH] Clarify pci_iomap() usage for MMIO-only devices Luis R. Rodriguez
2007-09-18 10:34 ` Alan Cox
2007-09-18 18:46   ` Luis R. Rodriguez
2007-09-18 19:03     ` Linus Torvalds
2007-09-18 19:07       ` Luis R. Rodriguez
2007-09-18 19:22         ` Linus Torvalds
2007-09-18 20:12           ` Luis R. Rodriguez
2007-09-18 20:30             ` Linus Torvalds
2007-09-18 21:02               ` Luis R. Rodriguez
2007-09-18 21:14                 ` Linus Torvalds
2007-09-18 21:30                   ` Jeff Garzik
2007-09-18 21:42                     ` Linus Torvalds
2007-09-18 22:25                       ` Linus Torvalds
2007-09-18 22:21               ` Benjamin Herrenschmidt [this message]
2007-09-18 22:36                 ` Linus Torvalds
2007-09-18 20:21           ` Jeff Garzik
2007-09-18 22:20             ` Benjamin Herrenschmidt
2007-09-18 23:08               ` Jeff Garzik
2007-09-18 23:27                 ` Linus Torvalds
2007-09-18 22:16       ` Benjamin Herrenschmidt
2007-09-18 22:25       ` Alan Cox
2007-09-19 15:07         ` Nick Kossifidis

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=1190154117.6403.127.camel@localhost.localdomain \
    --to=benh@kernel.crashing.org \
    --cc=alan@lxorguk.ukuu.org.uk \
    --cc=jeff@garzik.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-wireless@vger.kernel.org \
    --cc=linville@tuxdriver.com \
    --cc=mcgrof@gmail.com \
    --cc=torvalds@linux-foundation.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