On Tue, 05 Apr 2022, Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> wrote:
> From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
>
> In addition to the fp_timing,dvo_timing,panel_pnp_id tables
> there also exists a panel_name table. Unlike the others this
> is just one offset+table_size even though there are still 16
> actual panel_names in the data block.
>
> The panel_name table made its first appearance somewhere
> around VBT version 156-163. The exact version is not known.
> But we don't need to know that since we can just check whether
> the pointers block has enough room for it or not.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
> ---
> drivers/gpu/drm/i915/display/intel_bios.c | 18 +++++++++++++++++-
> drivers/gpu/drm/i915/display/intel_vbt_defs.h | 5 +++++
> 2 files changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index 925f521f1f84..799c1fe36b23 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -206,7 +206,7 @@ static const struct {
> static bool validate_lfp_data_ptrs(const void *bdb,
> const struct bdb_lvds_lfp_data_ptrs *ptrs)
> {
> - int fp_timing_size, dvo_timing_size, panel_pnp_id_size;
> + int fp_timing_size, dvo_timing_size, panel_pnp_id_size, panel_name_size;
> int data_block_size, lfp_data_size;
> int i;
>
> @@ -221,6 +221,7 @@ static bool validate_lfp_data_ptrs(const void *bdb,
> fp_timing_size = ptrs->ptr[0].fp_timing.table_size;
> dvo_timing_size = ptrs->ptr[0].dvo_timing.table_size;
> panel_pnp_id_size = ptrs->ptr[0].panel_pnp_id.table_size;
> + panel_name_size = ptrs->panel_name.table_size;
>
> /* fp_timing has variable size */
> if (fp_timing_size < 32 ||
> @@ -228,6 +229,11 @@ static bool validate_lfp_data_ptrs(const void *bdb,
> panel_pnp_id_size != sizeof(struct lvds_pnp_id))
> return false;
>
> + /* panel_name is not present in old VBTs */
> + if (panel_name_size != 0 &&
> + panel_name_size != sizeof(struct lvds_lfp_panel_name))
> + return false;
> +
> lfp_data_size = ptrs->ptr[1].fp_timing.offset - ptrs->ptr[0].fp_timing.offset;
> if (16 * lfp_data_size > data_block_size)
> return false;
> @@ -268,6 +274,9 @@ static bool validate_lfp_data_ptrs(const void *bdb,
> return false;
> }
>
> + if (ptrs->panel_name.offset + 16 * panel_name_size > data_block_size)
> + return false;
> +
> return true;
> }
>
> @@ -291,6 +300,13 @@ static bool fixup_lfp_data_ptrs(const void *bdb, void *ptrs_block)
> ptrs->ptr[i].panel_pnp_id.offset -= offset;
> }
>
> + if (ptrs->panel_name.table_size) {
> + if (ptrs->panel_name.offset < offset)
> + return false;
> +
> + ptrs->panel_name.offset -= offset;
> + }
> +
> return validate_lfp_data_ptrs(bdb, ptrs);
> }
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vbt_defs.h b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> index d727fcd6cdab..e4a11c3e3f3e 100644
> --- a/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> +++ b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
> @@ -737,6 +737,7 @@ struct lvds_lfp_data_ptr {
> struct bdb_lvds_lfp_data_ptrs {
> u8 lvds_entries; /* followed by one or more lvds_data_ptr structs */
> struct lvds_lfp_data_ptr ptr[16];
> + struct lvds_lfp_data_ptr_table panel_name; /* 156-163? */
> } __packed;
>
> /*
> @@ -778,6 +779,10 @@ struct bdb_lvds_lfp_data {
> struct lvds_lfp_data_entry data[16];
> } __packed;
>
> +struct lvds_lfp_panel_name {
> + u8 name[13];
> +} __packed;
> +
> /*
> * Block 43 - LFP Backlight Control Data Block
> */
--
Jani Nikula, Intel Open Source Graphics Center
