drm/i915/bios: add support for querying DSC details for encoder

Add function for retrieving the DSC data for an encoder.

Initially, this is DSI specific, as DP does not use VBT settings for DSC
at all. It's also not very pretty.

In the future we might have a pointer from encoder to the child device,
which would make the child device list query here so much more sensible.

v3:
- use crtc_state instead of pipe_config
- return true by default from intel_bios_get_dsc_params()
- expand the comment about rc_buffer_block_size and rc_buffer_size

v2:
- make more robust, debug log errors better

Bspec: 29885
Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b895c349d964d70e4cad26f12a629ea1898bfcc2.1575974743.git.jani.nikula@intel.com

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_bios.h b/drivers/gpu/drm/i915/display/intel_bios.h
index 98f064828a57..d6a0c29d37ac 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.h
+++ b/drivers/gpu/drm/i915/display/intel_bios.h
@@ -35,6 +35,8 @@
 #include <drm/i915_drm.h>
 
 struct drm_i915_private;
+struct intel_crtc_state;
+struct intel_encoder;
 enum port;
 
 enum intel_backlight_type {
@@ -242,5 +244,8 @@ bool intel_bios_is_port_hpd_inverted(const struct drm_i915_private *i915,
 bool intel_bios_is_lspcon_present(const struct drm_i915_private *i915,
 				  enum port port);
 enum aux_ch intel_bios_port_aux_ch(struct drm_i915_private *dev_priv, enum port port);
+bool intel_bios_get_dsc_params(struct intel_encoder *encoder,
+			       struct intel_crtc_state *crtc_state,
+			       int dsc_max_bpc);
 
 #endif /* _INTEL_BIOS_H_ */