Commit a8f65ba3 authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/dsc: add helper for calculating rc buffer size from DPCD 



Add a helper for calculating the rc buffer size from the DCPD offsets
DP_DSC_RC_BUF_BLK_SIZE and DP_DSC_RC_BUF_SIZE.

Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Harry Wentland <hwentlan@amd.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: default avatarVandita Kulkarni <vandita.kulkarni@intel.com>
Acked-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/6c6aee22740fe7a8cf2b8e768bfda378850cf59a.1607429866.git.jani.nikula@intel.com
parent 420798a0

drivers/gpu/drm/drm_dsc.c

+27 −0
Original line number Diff line number Diff line
@@ -49,6 +49,33 @@ void drm_dsc_dp_pps_header_init(struct dp_sdp_header *pps_header) 
}

EXPORT_SYMBOL(drm_dsc_dp_pps_header_init);



/**

 * drm_dsc_dp_rc_buffer_size - get rc buffer size in bytes

 * @rc_buffer_block_size: block size code, according to DPCD offset 62h

 * @rc_buffer_size: number of blocks - 1, according to DPCD offset 63h

 *

 * return:

 * buffer size in bytes, or 0 on invalid input

 */

int drm_dsc_dp_rc_buffer_size(u8 rc_buffer_block_size, u8 rc_buffer_size)

{

	int size = 1024 * (rc_buffer_size + 1);



	switch (rc_buffer_block_size) {

	case DP_DSC_RC_BUF_BLK_SIZE_1:

		return 1 * size;

	case DP_DSC_RC_BUF_BLK_SIZE_4:

		return 4 * size;

	case DP_DSC_RC_BUF_BLK_SIZE_16:

		return 16 * size;

	case DP_DSC_RC_BUF_BLK_SIZE_64:

		return 64 * size;

	default:

		return 0;

	}

}

EXPORT_SYMBOL(drm_dsc_dp_rc_buffer_size);



/**

 * drm_dsc_pps_payload_pack() - Populates the DSC PPS

 *

include/drm/drm_dsc.h

+1 −0
Original line number Diff line number Diff line
@@ -602,6 +602,7 @@ struct drm_dsc_pps_infoframe { 
} __packed;



void drm_dsc_dp_pps_header_init(struct dp_sdp_header *pps_header);

int drm_dsc_dp_rc_buffer_size(u8 rc_buffer_block_size, u8 rc_buffer_size);

void drm_dsc_pps_payload_pack(struct drm_dsc_picture_parameter_set *pps_sdp,

				const struct drm_dsc_config *dsc_cfg);

int drm_dsc_compute_rc_parameters(struct drm_dsc_config *vdsc_cfg);