[Intel-xe] [PATCH] fixup! drm/xe/uapi: support pat_index selection with vm_bind

[Souza, Jose]

On Fri, 2023-12-01 at 15:11 +0000, Matthew Auld wrote:
> Add a note in the docs for NULL bindings and corresponding pat_index:
> 
> https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26430
> 

Reviewed-by: José Roberto de Souza <jose.souza at intel.com>

> Testcase: igt at xe_pat@pat-index-all
> Signed-off-by: Matthew Auld <matthew.auld at intel.com>
> Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
> Cc: José Roberto de Souza <jose.souza at intel.com>
> ---
>  include/uapi/drm/xe_drm.h | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/include/uapi/drm/xe_drm.h b/include/uapi/drm/xe_drm.h
> index 58e655981992..1a844fa7af8a 100644
> --- a/include/uapi/drm/xe_drm.h
> +++ b/include/uapi/drm/xe_drm.h
> @@ -673,6 +673,12 @@ struct drm_xe_vm_bind_op {
>  	 *
>  	 * Note: For userptr and externally imported dma-buf the kernel expects
>  	 * either 1WAY or 2WAY for the @pat_index.
> +	 *
> +	 * For DRM_XE_VM_BIND_FLAG_NULL bindings there are no KMD restrictions
> +	 * on the @pat_index. For such mappings there is no actual memory being
> +	 * mapped (the address in the PTE is invalid), so the various PAT memory
> +	 * attributes likely do not apply.  Simply leaving as zero is one
> +	 * option (still a valid pat_index).
>  	 */
>  	__u16 pat_index;
>