[PATCH 6/7] drm/amd/display: Don't print errors for nonexistent connectors

[Alex Deucher]

On Thu, Jul 31, 2025 at 2:03 PM Timur Kristóf <timur.kristof at gmail.com> wrote:
>
> When getting the number of connectors, the VBIOS reports
> the number of valid indices, but it doesn't say which indices
> are valid, and not every valid index has an actual connector.
> If we don't find a connector on an index, that is not an error.
>
> Considering these are not actual errors, don't litter the logs.
>
> Fixes: 60df5628144b ("drm/amd/display: handle invalid connector indices")
> Signed-off-by: Timur Kristóf <timur.kristof at gmail.com>

Acked-by: Alex Deucher <alexander.deucher at amd.com>

> ---
>  drivers/gpu/drm/amd/display/dc/bios/bios_parser.c |  5 +----
>  drivers/gpu/drm/amd/display/dc/core/dc.c          | 15 ++++++++++++++-
>  2 files changed, 15 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/bios/bios_parser.c b/drivers/gpu/drm/amd/display/dc/bios/bios_parser.c
> index 67f08495b7e6..154fd2c18e88 100644
> --- a/drivers/gpu/drm/amd/display/dc/bios/bios_parser.c
> +++ b/drivers/gpu/drm/amd/display/dc/bios/bios_parser.c
> @@ -174,11 +174,8 @@ static struct graphics_object_id bios_parser_get_connector_id(
>                 return object_id;
>         }
>
> -       if (tbl->ucNumberOfObjects <= i) {
> -               dm_error("Can't find connector id %d in connector table of size %d.\n",
> -                        i, tbl->ucNumberOfObjects);
> +       if (tbl->ucNumberOfObjects <= i)
>                 return object_id;
> -       }
>
>         id = le16_to_cpu(tbl->asObjects[i].usObjectID);
>         object_id = object_id_from_bios_object_id(id);
> diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
> index cf3893a2f8ce..33d6a5116aad 100644
> --- a/drivers/gpu/drm/amd/display/dc/core/dc.c
> +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
> @@ -217,11 +217,24 @@ static bool create_links(
>                 connectors_num,
>                 num_virtual_links);
>
> -       // condition loop on link_count to allow skipping invalid indices
> +       /* When getting the number of connectors, the VBIOS reports the number of valid indices,
> +        * but it doesn't say which indices are valid, and not every index has an actual connector.
> +        * So, if we don't find a connector on an index, that is not an error.
> +        *
> +        * - There is no guarantee that the first N indices will be valid
> +        * - VBIOS may report a higher amount of valid indices than there are actual connectors
> +        * - Some VBIOS have valid configurations for more connectors than there actually are
> +        *   on the card. This may be because the manufacturer used the same VBIOS for different
> +        *   variants of the same card.
> +        */
>         for (i = 0; dc->link_count < connectors_num && i < MAX_LINKS; i++) {
> +               struct graphics_object_id connector_id = bios->funcs->get_connector_id(bios, i);
>                 struct link_init_data link_init_params = {0};
>                 struct dc_link *link;
>
> +               if (connector_id.id == CONNECTOR_ID_UNKNOWN)
> +                       continue;
> +
>                 DC_LOG_DC("BIOS object table - printing link object info for connector number: %d, link_index: %d", i, dc->link_count);
>
>                 link_init_params.ctx = dc->ctx;
> --
> 2.50.1
>