Re: [PATCH] drm/ttm: Support 52-bit PAs in ttm_place

["Christian König" <christian.koenig@amd.com>]

On 5/13/26 00:31, Felix Kuehling wrote:
> fpfn and lpfn in struct ttm_place are 32-bit page numbers. With 4KB page
> size this can support up to 44-bit physical addressing. Grow these to
> unsigned long to support larger physical addresses.
> 
> Signed-off-by: Felix Kuehling <felix.kuehling@amd.com>
> ---
>  include/drm/ttm/ttm_placement.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/include/drm/ttm/ttm_placement.h b/include/drm/ttm/ttm_placement.h
> index b510a4812609..3e88869c0f58 100644
> --- a/include/drm/ttm/ttm_placement.h
> +++ b/include/drm/ttm/ttm_placement.h
> @@ -81,8 +81,8 @@
>   * Structure indicating a possible place to put an object.
>   */
>  struct ttm_place {
> -	unsigned	fpfn;
> -	unsigned	lpfn;
> +	unsigned long	fpfn;
> +	unsigned long	lpfn;

That should be uint64_t instead, long is CPU architecture dependent and we clearly don't want that in TTM.

But apart from that looks reasonable to me.

Regards,
Christian.

>  	uint32_t	mem_type;
>  	uint32_t	flags;
>  };