From: "Gabriel L. Somlo" <somlo@cmu.edu>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: mark.rutland@arm.com, peter.maydell@linaro.org,
matt@codeblueprint.co.uk, stefanha@gmail.com,
qemu-devel@nongnu.org, eric@anholt.net, kraxel@redhat.com,
linux-api@vger.kernel.org, agross@codeaurora.org,
pawel.moll@arm.com, zajec5@gmail.com,
rmk+kernel@arm.linux.org.uk, lersek@redhat.com,
devicetree@vger.kernel.org, ehabkost@redhat.com, arnd@arndb.de,
ijc+devicetree@hellion.org.uk, galak@codeaurora.org,
leif.lindholm@linaro.org, robh+dt@kernel.org,
pbonzini@redhat.com, rth@twiddle.net, ard.biesheuvel@linaro.org,
gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
luto@amacapital.net, hanjun.guo@linaro.org, sudeep.holla@arm.com,
imammedo@redhat.com, revol@free.fr
Subject: Re: [Qemu-devel] [PATCH v8 1/4] firmware: introduce sysfs driver for QEMU's fw_cfg device
Date: Sun, 21 Feb 2016 12:20:10 -0500 [thread overview]
Message-ID: <20160221172010.GA4711@GLSMBP.INI.CMU.EDU> (raw)
In-Reply-To: <20160221150904-mutt-send-email-mst@redhat.com>
On Sun, Feb 21, 2016 at 03:10:30PM +0200, Michael S. Tsirkin wrote:
> On Sun, Feb 21, 2016 at 08:06:17AM -0500, Gabriel L. Somlo wrote:
> >
> > >
> > > > +#if !(defined(FW_CFG_CTRL_OFF) && defined(FW_CTRL_DATA_OFF))
> > > > +# if (defined(CONFIG_ARM) || defined(CONFIG_ARM64))
> > > > +# define FW_CFG_CTRL_OFF 0x08
> > > > +# define FW_CFG_DATA_OFF 0x00
> > > > +# elif (defined(CONFIG_PPC_PMAC) || defined(CONFIG_SPARC32)) /* ppc/mac,sun4m */
> > > > +# define FW_CFG_CTRL_OFF 0x00
> > > > +# define FW_CFG_DATA_OFF 0x02
> > > > +# elif (defined(CONFIG_X86) || defined(CONFIG_SPARC64)) /* x86, sun4u */
> > > > +# define FW_CFG_CTRL_OFF 0x00
> > > > +# define FW_CFG_DATA_OFF 0x01
> > > > +# else
> > > > +# warning "QEMU FW_CFG may not be available on this architecture!"
> > > > +# define FW_CFG_CTRL_OFF 0x00
> > > > +# define FW_CFG_DATA_OFF 0x01
> > >
> > > Better not try hacks like this, they are hard
> > > to support down the road. Please only list what is tested and
> > > actually exposed by QEMU.
> >
> > I was looking for a standard way to advertise register offsets within
> > the ioport or mmio region assigned to fw_cfg, but right now the answer
> > is "there isn't one", and "register offsets are an arch specific
> > detail". As such, the only reasonable way I saw was to copy the same
> > values used in the QEMU source.
> >
> > See also:
> > https://lists.gnu.org/archive/html/qemu-devel/2015-11/msg05037.html
> >
> > Thanks much,
> > --Gabriel
>
> My point is you don't know what will qemu do on these
> other arches which do not at the moment have fw cfg.
> So don't try to guess!
Oh, you mean for the "else". I originally wanted to be able to compile
this on any architecture and wanted some dummy defaults I could
override on the command line. But now we're already restricting this
to known architectures only, so I'll send a patch turning the warning
into an error, and removing the #defines for the "else" branch above.
Sorry I misunderstood you the first time around :)
Thanks,
--Gabriel
next prev parent reply other threads:[~2016-02-21 17:20 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-28 14:23 [Qemu-devel] [PATCH v8 0/4] SysFS driver for QEMU fw_cfg device Gabriel L. Somlo
2016-01-28 14:23 ` [Qemu-devel] [PATCH v8 1/4] firmware: introduce sysfs driver for QEMU's " Gabriel L. Somlo
2016-02-21 8:30 ` Michael S. Tsirkin
2016-02-21 13:06 ` Gabriel L. Somlo
2016-02-21 13:10 ` Michael S. Tsirkin
2016-02-21 17:20 ` Gabriel L. Somlo [this message]
2016-02-21 13:14 ` Michael S. Tsirkin
2016-02-22 20:14 ` Michael S. Tsirkin
2016-02-22 20:26 ` Gabriel L. Somlo
2016-02-23 5:07 ` Michael S. Tsirkin
2016-02-23 13:47 ` Gabriel L. Somlo
2016-02-23 14:14 ` Michael S. Tsirkin
2016-02-24 0:03 ` Gabriel L. Somlo
2016-01-28 14:23 ` [Qemu-devel] [PATCH v8 2/4] kobject: export kset_find_obj() for module use Gabriel L. Somlo
2016-02-07 7:24 ` Greg KH
2016-02-07 14:27 ` Gabriel L. Somlo
2016-01-28 14:23 ` [Qemu-devel] [PATCH v8 3/4] firmware: create directory hierarchy for sysfs fw_cfg entries Gabriel L. Somlo
2016-01-28 14:23 ` [Qemu-devel] [PATCH v8 4/4] devicetree: update documentation for fw_cfg ARM bindings Gabriel L. Somlo
2016-02-03 22:47 ` [Qemu-devel] [PATCH v8 0/4] SysFS driver for QEMU fw_cfg device Matt Fleming
2016-02-10 1:38 ` Greg KH
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=20160221172010.GA4711@GLSMBP.INI.CMU.EDU \
--to=somlo@cmu.edu \
--cc=agross@codeaurora.org \
--cc=ard.biesheuvel@linaro.org \
--cc=arnd@arndb.de \
--cc=devicetree@vger.kernel.org \
--cc=ehabkost@redhat.com \
--cc=eric@anholt.net \
--cc=galak@codeaurora.org \
--cc=gregkh@linuxfoundation.org \
--cc=hanjun.guo@linaro.org \
--cc=ijc+devicetree@hellion.org.uk \
--cc=imammedo@redhat.com \
--cc=kraxel@redhat.com \
--cc=leif.lindholm@linaro.org \
--cc=lersek@redhat.com \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=mark.rutland@arm.com \
--cc=matt@codeblueprint.co.uk \
--cc=mst@redhat.com \
--cc=pawel.moll@arm.com \
--cc=pbonzini@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
--cc=revol@free.fr \
--cc=rmk+kernel@arm.linux.org.uk \
--cc=robh+dt@kernel.org \
--cc=rth@twiddle.net \
--cc=stefanha@gmail.com \
--cc=sudeep.holla@arm.com \
--cc=zajec5@gmail.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).