On Tue, 05 Apr 2022, Ville Syrjala <ville.syrj...@linux.intel.com> wrote:
> From: Ville Syrjälä <ville.syrj...@linux.intel.com>
>
> Now that we've sufficiently validated the LFP data pointers we
> can trust them.
>
> Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nik...@intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_bios.c | 60 ++++++-----------------
> 1 file changed, 16 insertions(+), 44 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c
> b/drivers/gpu/drm/i915/display/intel_bios.c
> index cd82ea4de8e1..925f521f1f84 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -397,44 +397,19 @@ fill_detail_timing_data(struct drm_display_mode
> *panel_fixed_mode,
> }
>
> static const struct lvds_dvo_timing *
> -get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *lvds_lfp_data,
> - const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs,
> +get_lvds_dvo_timing(const struct bdb_lvds_lfp_data *data,
> + const struct bdb_lvds_lfp_data_ptrs *ptrs,
> int index)
> {
> - /*
> - * the size of fp_timing varies on the different platform.
> - * So calculate the DVO timing relative offset in LVDS data
> - * entry to get the DVO timing entry
> - */
> -
> - int lfp_data_size =
> - lvds_lfp_data_ptrs->ptr[1].dvo_timing.offset -
> - lvds_lfp_data_ptrs->ptr[0].dvo_timing.offset;
> - int dvo_timing_offset =
> - lvds_lfp_data_ptrs->ptr[0].dvo_timing.offset -
> - lvds_lfp_data_ptrs->ptr[0].fp_timing.offset;
> - char *entry = (char *)lvds_lfp_data->data + lfp_data_size * index;
> -
> - return (struct lvds_dvo_timing *)(entry + dvo_timing_offset);
> + return (const void *)data + ptrs->ptr[index].dvo_timing.offset;
> }
>
> -/* get lvds_fp_timing entry
> - * this function may return NULL if the corresponding entry is invalid
> - */
> static const struct lvds_fp_timing *
> get_lvds_fp_timing(const struct bdb_lvds_lfp_data *data,
> const struct bdb_lvds_lfp_data_ptrs *ptrs,
> int index)
> {
> - u16 data_size = ((const u16 *)data)[-1]; /* stored in header */
> - size_t ofs;
> -
> - if (index >= ARRAY_SIZE(ptrs->ptr))
> - return NULL;
> - ofs = ptrs->ptr[index].fp_timing.offset;
> - if (ofs + sizeof(struct lvds_fp_timing) > data_size)
> - return NULL;
> - return (const struct lvds_fp_timing *)((const u8 *)data + ofs);
> + return (const void *)data + ptrs->ptr[index].fp_timing.offset;
> }
>
> /* Parse general panel options */
> @@ -499,8 +474,7 @@ parse_panel_options(struct drm_i915_private *i915)
>
> /* Try to find integrated panel timing data */
> static void
> -parse_lfp_panel_dtd(struct drm_i915_private *i915,
> - const struct bdb_header *bdb)
> +parse_lfp_panel_dtd(struct drm_i915_private *i915)
> {
> const struct bdb_lvds_lfp_data *lvds_lfp_data;
> const struct bdb_lvds_lfp_data_ptrs *lvds_lfp_data_ptrs;
> @@ -536,15 +510,14 @@ parse_lfp_panel_dtd(struct drm_i915_private *i915,
> fp_timing = get_lvds_fp_timing(lvds_lfp_data,
> lvds_lfp_data_ptrs,
> panel_type);
> - if (fp_timing) {
> - /* check the resolution, just to be sure */
> - if (fp_timing->x_res == panel_fixed_mode->hdisplay &&
> - fp_timing->y_res == panel_fixed_mode->vdisplay) {
> - i915->vbt.bios_lvds_val = fp_timing->lvds_reg_val;
> - drm_dbg_kms(&i915->drm,
> - "VBT initial LVDS value %x\n",
> - i915->vbt.bios_lvds_val);
> - }
> +
> + /* check the resolution, just to be sure */
> + if (fp_timing->x_res == panel_fixed_mode->hdisplay &&
> + fp_timing->y_res == panel_fixed_mode->vdisplay) {
> + i915->vbt.bios_lvds_val = fp_timing->lvds_reg_val;
> + drm_dbg_kms(&i915->drm,
> + "VBT initial LVDS value %x\n",
> + i915->vbt.bios_lvds_val);
> }
> }
>
> @@ -627,8 +600,7 @@ parse_generic_dtd(struct drm_i915_private *i915)
> }
>
> static void
> -parse_panel_dtd(struct drm_i915_private *i915,
> - const struct bdb_header *bdb)
> +parse_panel_dtd(struct drm_i915_private *i915)
> {
> /*
> * Older VBTs provided provided DTD information for internal displays
> @@ -641,7 +613,7 @@ parse_panel_dtd(struct drm_i915_private *i915,
> if (i915->vbt.version >= 229)
> parse_generic_dtd(i915);
> if (!i915->vbt.lfp_lvds_vbt_mode)
> - parse_lfp_panel_dtd(i915, bdb);
> + parse_lfp_panel_dtd(i915);
> }
>
> static void
> @@ -2720,7 +2692,7 @@ void intel_bios_init(struct drm_i915_private *i915)
> parse_general_features(i915);
> parse_general_definitions(i915);
> parse_panel_options(i915);
> - parse_panel_dtd(i915, bdb);
> + parse_panel_dtd(i915);
> parse_lfp_backlight(i915);
> parse_sdvo_panel_data(i915);
> parse_driver_features(i915);
--
Jani Nikula, Intel Open Source Graphics Center
