Re: [PATCH 35/36] doc, device-tree: introduce 'colors' property

[Julien Grall <julien@xxxxxxx>]

Hi,

On 04/03/2022 17:47, Marco Solieri wrote:
> From: Luca Miccio <lucmiccio@xxxxxxxxx>
>
> Dom0less uses device tree for DomUs when booting them without using
> Dom0. Add a new device tree property 'colors' that specifies the
> coloring configuration for DomUs when using Dom0less.
>
> Signed-off-by: Luca Miccio <lucmiccio@xxxxxxxxx>
> Signed-off-by: Marco Solieri <marco.solieri@xxxxxxxxxxxxxxx>
The documentation is small enough that I would prefer if this is folded 
in the patch parsing the property.
> ---
>   docs/misc/arm/device-tree/booting.txt | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/docs/misc/arm/device-tree/booting.txt 
> b/docs/misc/arm/device-tree/booting.txt
> index a94125394e..44971bfe60 100644
> --- a/docs/misc/arm/device-tree/booting.txt
> +++ b/docs/misc/arm/device-tree/booting.txt
> @@ -162,6 +162,9 @@ with the following properties:
>   
>       An integer specifying the number of vcpus to allocate to the guest.
>   
> +- colors
> +    A 64 bit bitmask specifying the color configuration for the guest.
Why are we limiting dom0less domUs to 64 colors when Xen can support up 
to 128 colors (potentially more in the future)?
To avoid tie the bindings too much to Xen, I would instead explicitly 
list the colors. Something like:
colors = < 10 20 30 >

This would also help users that manually write the DT to confirm they 
put the correct numbers.
Cheers,

--
Julien Grall