From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Luis R. Rodriguez" <mcgrof@gmail.com>,
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: Tue, 18 Sep 2007 23:25:46 +0100 [thread overview]
Message-ID: <20070918232546.004af9ff@the-village.bc.nu> (raw)
In-Reply-To: <alpine.LFD.0.999.0709181159440.16478@woody.linux-foundation.org>
> If you use ioport_map/unmap, then you really *should* access them with the
> proper iomem accessors (ioread/iowrite). The fact that it may happen to
> work (when using the default lib/iomap.c implementation, at least) on
> some architectures and with the current implementation still doesn't mean
> that you should necessarily use readb/writeb.
Another reason we should enforce the use of ioread/iowrite is that some
platforms do daft things like map mmio type devices through indirect
register access. Sparc PCMCIA is a classic example. The only sane way to
make these work is to require ioread/iowrite is used with iomap
next prev parent reply other threads:[~2007-09-18 22:19 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
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 [this message]
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=20070918232546.004af9ff@the-village.bc.nu \
--to=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