diff mbox

[Xen-devel,10/10] xen: arm: update multiboot device tree bindings.

Message ID 1402919103-29642-10-git-send-email-ian.campbell@citrix.com
State New
Headers show

Commit Message

Ian Campbell June 16, 2014, 11:45 a.m. UTC
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
 docs/misc/arm/device-tree/booting.txt |   24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

Comments

Stefano Stabellini June 18, 2014, 2:56 p.m. UTC | #1
On Mon, 16 Jun 2014, Ian Campbell wrote:
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> ---
>  docs/misc/arm/device-tree/booting.txt |   24 ++++++++++++++++++------
>  1 file changed, 18 insertions(+), 6 deletions(-)
> 
> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
> index bfb8d01..92af119 100644
> --- a/docs/misc/arm/device-tree/booting.txt
> +++ b/docs/misc/arm/device-tree/booting.txt
> @@ -8,15 +8,27 @@ Each node contains the following properties:
>  
>  - compatible
>  
> -	Must be:
> +	Must always include at least:
>  
> -		"xen,<type>", "xen,multiboot-module"
> +		"multiboot,module"

As it stands this conflicts with the statement below that we are
compatible with Xen 4.4: the old multiboot compatible strings didn't
include "multiboot,module".
You might want to reword it.


> -	where <type> must be one of:
> +	Optionally a more specific compatible string may be used in
> +	addition to the above. One of:

We should probably recommend the usage of a more specific string in
addition to "multiboot,module".


> -	- "linux-zimage" -- the dom0 kernel
> -	- "linux-initrd" -- the dom0 ramdisk
> -	- "xsm-policy"	 -- XSM policy blob
> +	- "multiboot,kernel"	-- the dom0 kernel
> +	- "multiboot,ramdisk"	-- the dom0 ramdisk
> +	- "xen,xsm-policy"	-- XSM policy blob
> +
> +	For compatibility with Xen 4.4 the following are also
> +	supported:
> +
> +		"xen,multiboot-module" equivalent to "multiboot,module"
> +		"xen,linux-zimage" equivalent to "multiboot,kernel"
> +		"xen,linux-initrd" equivalent to "multiboot,ramdisk"
> +
> +	Xen 4.4 does not know the "multiboot,*" compatibility
> +	strings. Also when using Xen 4.4 the more specific
> +	"xen,linux-*" names are non-optional.
Ian Campbell June 18, 2014, 3:17 p.m. UTC | #2
On Wed, 2014-06-18 at 15:56 +0100, Stefano Stabellini wrote:
> On Mon, 16 Jun 2014, Ian Campbell wrote:
> > Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> > ---
> >  docs/misc/arm/device-tree/booting.txt |   24 ++++++++++++++++++------
> >  1 file changed, 18 insertions(+), 6 deletions(-)
> > 
> > diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
> > index bfb8d01..92af119 100644
> > --- a/docs/misc/arm/device-tree/booting.txt
> > +++ b/docs/misc/arm/device-tree/booting.txt
> > @@ -8,15 +8,27 @@ Each node contains the following properties:
> >  
> >  - compatible
> >  
> > -	Must be:
> > +	Must always include at least:
> >  
> > -		"xen,<type>", "xen,multiboot-module"
> > +		"multiboot,module"
> 
> As it stands this conflicts with the statement below that we are
> compatible with Xen 4.4: the old multiboot compatible strings didn't
> include "multiboot,module".
> You might want to reword it.

I'm not sure what you mean or I would. 

I don't think the doc says that we are compatible with Xen 4.4, it says
that in order to be compatible with Xen 4.4 the user should... Is that
what I need to clarify perhaps?

> > -	where <type> must be one of:
> > +	Optionally a more specific compatible string may be used in
> > +	addition to the above. One of:
> 
> We should probably recommend the usage of a more specific string in
> addition to "multiboot,module".

"Normally a more specific compatible string should be used in addition
to the above" perhaps?

At some point I'd like to see us doing more probing of magic numbers
(e.g. x86 does this for the XSM policy).

Ian.
Stefano Stabellini June 18, 2014, 3:22 p.m. UTC | #3
On Wed, 18 Jun 2014, Ian Campbell wrote:
> On Wed, 2014-06-18 at 15:56 +0100, Stefano Stabellini wrote:
> > On Mon, 16 Jun 2014, Ian Campbell wrote:
> > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> > > ---
> > >  docs/misc/arm/device-tree/booting.txt |   24 ++++++++++++++++++------
> > >  1 file changed, 18 insertions(+), 6 deletions(-)
> > > 
> > > diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
> > > index bfb8d01..92af119 100644
> > > --- a/docs/misc/arm/device-tree/booting.txt
> > > +++ b/docs/misc/arm/device-tree/booting.txt
> > > @@ -8,15 +8,27 @@ Each node contains the following properties:
> > >  
> > >  - compatible
> > >  
> > > -	Must be:
> > > +	Must always include at least:
> > >  
> > > -		"xen,<type>", "xen,multiboot-module"
> > > +		"multiboot,module"
> > 
> > As it stands this conflicts with the statement below that we are
> > compatible with Xen 4.4: the old multiboot compatible strings didn't
> > include "multiboot,module".
> > You might want to reword it.
> 
> I'm not sure what you mean or I would. 
> 
> I don't think the doc says that we are compatible with Xen 4.4, it says
> that in order to be compatible with Xen 4.4 the user should... Is that
> what I need to clarify perhaps?

The doc says "For compatibility with Xen 4.4 the following are also
supported". From that I assumed that we are compatible with Xen 4.4....


> > > -	where <type> must be one of:
> > > +	Optionally a more specific compatible string may be used in
> > > +	addition to the above. One of:
> > 
> > We should probably recommend the usage of a more specific string in
> > addition to "multiboot,module".
> 
> "Normally a more specific compatible string should be used in addition
> to the above" perhaps?

That's good. Or maybe "A more specific compatible string can and should
be used in addition to the above".


> At some point I'd like to see us doing more probing of magic numbers
> (e.g. x86 does this for the XSM policy).
Ian Campbell June 18, 2014, 3:24 p.m. UTC | #4
On Wed, 2014-06-18 at 16:22 +0100, Stefano Stabellini wrote:
> On Wed, 18 Jun 2014, Ian Campbell wrote:
> > On Wed, 2014-06-18 at 15:56 +0100, Stefano Stabellini wrote:
> > > On Mon, 16 Jun 2014, Ian Campbell wrote:
> > > > Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> > > > ---
> > > >  docs/misc/arm/device-tree/booting.txt |   24 ++++++++++++++++++------
> > > >  1 file changed, 18 insertions(+), 6 deletions(-)
> > > > 
> > > > diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
> > > > index bfb8d01..92af119 100644
> > > > --- a/docs/misc/arm/device-tree/booting.txt
> > > > +++ b/docs/misc/arm/device-tree/booting.txt
> > > > @@ -8,15 +8,27 @@ Each node contains the following properties:
> > > >  
> > > >  - compatible
> > > >  
> > > > -	Must be:
> > > > +	Must always include at least:
> > > >  
> > > > -		"xen,<type>", "xen,multiboot-module"
> > > > +		"multiboot,module"
> > > 
> > > As it stands this conflicts with the statement below that we are
> > > compatible with Xen 4.4: the old multiboot compatible strings didn't
> > > include "multiboot,module".
> > > You might want to reword it.
> > 
> > I'm not sure what you mean or I would. 
> > 
> > I don't think the doc says that we are compatible with Xen 4.4, it says
> > that in order to be compatible with Xen 4.4 the user should... Is that
> > what I need to clarify perhaps?
> 
> The doc says "For compatibility with Xen 4.4 the following are also
> supported". From that I assumed that we are compatible with Xen 4.4....

This is saying "in addition to what is described above we also support
XXX for compatibility with a previous way of doing things".

I wouldn't describe that as conflicting.
diff mbox

Patch

diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
index bfb8d01..92af119 100644
--- a/docs/misc/arm/device-tree/booting.txt
+++ b/docs/misc/arm/device-tree/booting.txt
@@ -8,15 +8,27 @@  Each node contains the following properties:
 
 - compatible
 
-	Must be:
+	Must always include at least:
 
-		"xen,<type>", "xen,multiboot-module"
+		"multiboot,module"
 
-	where <type> must be one of:
+	Optionally a more specific compatible string may be used in
+	addition to the above. One of:
 
-	- "linux-zimage" -- the dom0 kernel
-	- "linux-initrd" -- the dom0 ramdisk
-	- "xsm-policy"	 -- XSM policy blob
+	- "multiboot,kernel"	-- the dom0 kernel
+	- "multiboot,ramdisk"	-- the dom0 ramdisk
+	- "xen,xsm-policy"	-- XSM policy blob
+
+	For compatibility with Xen 4.4 the following are also
+	supported:
+
+		"xen,multiboot-module" equivalent to "multiboot,module"
+		"xen,linux-zimage" equivalent to "multiboot,kernel"
+		"xen,linux-initrd" equivalent to "multiboot,ramdisk"
+
+	Xen 4.4 does not know the "multiboot,*" compatibility
+	strings. Also when using Xen 4.4 the more specific
+	"xen,linux-*" names are non-optional.
 
 - reg