Re: [PATCH v3 09/10] xen: arm: update multiboot device tree bindings.

[Julien Grall <julien.grall@linaro.org>]

Hi Ian,

On 18/07/14 14:08, Ian Campbell wrote:
> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>

Acked-by: Julien Grall <julien.grall@linaro.org>

Regards,

> ---
> v2: (Try to) Clarify some wording, add examples to help.
> ---
>   docs/misc/arm/device-tree/booting.txt |   54 +++++++++++++++++++++++++++++----
>   1 file changed, 48 insertions(+), 6 deletions(-)
>
> diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt
> index bfb8d01..d967061 100644
> --- a/docs/misc/arm/device-tree/booting.txt
> +++ b/docs/misc/arm/device-tree/booting.txt
> @@ -8,15 +8,31 @@ Each node contains the following properties:
>
>   - compatible
>
> -	Must be:
> +	Must always include at least the generic compatiblity string:
>
> -		"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
> +
> +	It is normally recommended to include a more specific
> +	compatible string (if one applies) in addition to the generic
> +	string (which must always be present).
> +
> +        Xen 4.4 supported a different set of legacy compatible strings
> +	which remain supported such that systems supporting both 4.4
> +	and later can use a single DTB.
> +
> +	- "xen,multiboot-module" equivalent to "multiboot,module"
> +	- "xen,linux-zimage"     equivalent to "multiboot,kernel"
> +	- "xen,linux-initrd"     equivalent to "multiboot,ramdisk"
> +
> +	For compatibility with Xen 4.4 the more specific "xen,linux-*"
> +	names are non-optional and must be included.
>
>   - reg
>
> @@ -29,6 +45,32 @@ Each node contains the following properties:
>   	priority of this field vs. other mechanisms of specifying the
>   	bootargs for the kernel.
>
> +Examples
> +========
> +
> +A boot module of unspecified type:
> +
> +	module@0xc0000000 {
> +		compatible = "multiboot,module";
> +		reg = <0xc0000000 0x1234>;
> +		bootargs = "...";
> +	};
> +
> +A boot module containing a ramdisk:
> +
> +	module@0xd0000000 {
> +		compatible = "multiboot,ramdisk", "multiboot,module";
> +		reg = <0xd0000000 0x5678>;
> +	};
> +
> +The previous examples are compatible with Xen 4.5+ only.
> +
> +To be compatible with Xen 4.4 as well use the legacy names:
> +
> +	module@0xd0000000 {
> +		compatible = "xen,linux-initrd", "xen,multiboot-module";
> +		reg = <0xd0000000 0x5678>;
> +	};
>
>   Command lines
>   =============
>

-- 
Julien Grall