Re: [PATCH v4 11/12] xen/dt: ifdef out DEV_DT-related bits from device_tree.{c,h}

[Jan Beulich <jbeulich@xxxxxxxx>]

On 20.06.2025 20:28, Alejandro Vallejo wrote:
> device-tree.c stops requiring CONFIG_HAS_DEVICE_TREE_DISCOVERY and may
> function with DOM0LESS_BOOT.
> 
> Without this, there's a clash with x86's definition of device_t. Because
> x86 doesn't discover devices in the DT it can simply skip the code
> to do so during the unflattening phase.
> 
> Not a functional change on architectures that currently use these files,
> as they already select CONFIG_HAS_DEVICE_TREE_DISCOVERY.
> 
> Signed-off-by: Alejandro Vallejo <agarciav@xxxxxxx>
> ---
>  xen/common/device-tree/device-tree.c | 2 ++
>  xen/include/xen/device_tree.h        | 4 ++++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/xen/common/device-tree/device-tree.c 
> b/xen/common/device-tree/device-tree.c
> index 725ff71646..741e2ce585 100644
> --- a/xen/common/device-tree/device-tree.c
> +++ b/xen/common/device-tree/device-tree.c
> @@ -2029,9 +2029,11 @@ static unsigned long unflatten_dt_node(const void *fdt,
>              ((char *)pp->value)[sz - 1] = 0;
>              dt_dprintk("fixed up name for %s -> %s\n", pathp,
>                         (char *)pp->value);
> +#ifdef CONFIG_HAS_DEVICE_TREE_DISCOVERY
>              /* Generic device initialization */
>              np->dev.type = DEV_DT;
>              np->dev.of_node = np;
> +#endif /* CONFIG_HAS_DEVICE_TREE_DISCOVERY */
>          }
>      }

Without something said to that effect in the description, this contradicts

obj-$(CONFIG_HAS_DEVICE_TREE_DISCOVERY) += device-tree/

that the previous patch put in place, and that only the subsequent patch
will further change.

Jan