diff options
Diffstat (limited to 'drivers/gpu/drm/drm_dsc.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dsc.c | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/drivers/gpu/drm/drm_dsc.c b/drivers/gpu/drm/drm_dsc.c index bc2b23adb072..bce99f95c1a3 100644 --- a/drivers/gpu/drm/drm_dsc.c +++ b/drivers/gpu/drm/drm_dsc.c @@ -17,6 +17,12 @@ /** * DOC: dsc helpers * + * VESA specification for DP 1.4 adds a new feature called Display Stream + * Compression (DSC) used to compress the pixel bits before sending it on + * DP/eDP/MIPI DSI interface. DSC is required to be enabled so that the existing + * display interfaces can support high resolutions at higher frames rates uisng + * the maximum available link capacity of these interfaces. + * * These functions contain some common logic and helpers to deal with VESA * Display Stream Compression standard required for DSC on Display Port/eDP or * MIPI display interfaces. @@ -26,6 +32,13 @@ * drm_dsc_dp_pps_header_init() - Initializes the PPS Header * for DisplayPort as per the DP 1.4 spec. * @pps_sdp: Secondary data packet for DSC Picture Parameter Set + * as defined in &struct drm_dsc_pps_infoframe + * + * DP 1.4 spec defines the secondary data packet for sending the + * picture parameter infoframes from the source to the sink. + * This function populates the pps header defined in + * &struct drm_dsc_pps_infoframe as per the header bytes defined + * in &struct dp_sdp_header. */ void drm_dsc_dp_pps_header_init(struct drm_dsc_pps_infoframe *pps_sdp) { @@ -38,15 +51,20 @@ EXPORT_SYMBOL(drm_dsc_dp_pps_header_init); /** * drm_dsc_pps_infoframe_pack() - Populates the DSC PPS infoframe - * using the DSC configuration parameters in the order expected - * by the DSC Display Sink device. For the DSC, the sink device - * expects the PPS payload in the big endian format for the fields - * that span more than 1 byte. * * @pps_sdp: - * Secondary data packet for DSC Picture Parameter Set + * Secondary data packet for DSC Picture Parameter Set. This is defined + * by &struct drm_dsc_pps_infoframe * @dsc_cfg: - * DSC Configuration data filled by driver + * DSC Configuration data filled by driver as defined by + * &struct drm_dsc_config + * + * DSC source device sends a secondary data packet filled with all the + * picture parameter set (PPS) information required by the sink to decode + * the compressed frame. Driver populates the dsC PPS infoframe using the DSC + * configuration parameters in the order expected by the DSC Display Sink + * device. For the DSC, the sink device expects the PPS payload in the big + * endian format for the fields that span more than 1 byte. */ void drm_dsc_pps_infoframe_pack(struct drm_dsc_pps_infoframe *pps_sdp, const struct drm_dsc_config *dsc_cfg) |