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/* SPDX-License-Identifier: MIT
* Copyright (C) 2018 Intel Corp.
*
* Authors:
* Manasi Navare <manasi.d.navare@intel.com>
*/
#ifndef DRM_DSC_H_
#define DRM_DSC_H_
#include <drm/drm_dp_helper.h>
/* VESA Display Stream Compression DSC 1.2 constants */
#define DSC_NUM_BUF_RANGES 15
#define DSC_MUX_WORD_SIZE_8_10_BPC 48
#define DSC_MUX_WORD_SIZE_12_BPC 64
#define DSC_RC_PIXELS_PER_GROUP 3
#define DSC_SCALE_DECREMENT_INTERVAL_MAX 4095
#define DSC_RANGE_BPG_OFFSET_MASK 0x3f
/* DSC Rate Control Constants */
#define DSC_RC_MODEL_SIZE_CONST 8192
#define DSC_RC_EDGE_FACTOR_CONST 6
#define DSC_RC_TGT_OFFSET_HI_CONST 3
#define DSC_RC_TGT_OFFSET_LO_CONST 3
/* DSC PPS constants and macros */
#define DSC_PPS_VERSION_MAJOR_SHIFT 4
#define DSC_PPS_BPC_SHIFT 4
#define DSC_PPS_MSB_SHIFT 8
#define DSC_PPS_LSB_MASK (0xFF << 0)
#define DSC_PPS_BPP_HIGH_MASK (0x3 << 8)
#define DSC_PPS_VBR_EN_SHIFT 2
#define DSC_PPS_SIMPLE422_SHIFT 3
#define DSC_PPS_CONVERT_RGB_SHIFT 4
#define DSC_PPS_BLOCK_PRED_EN_SHIFT 5
#define DSC_PPS_INIT_XMIT_DELAY_HIGH_MASK (0x3 << 8)
#define DSC_PPS_SCALE_DEC_INT_HIGH_MASK (0xF << 8)
#define DSC_PPS_RC_TGT_OFFSET_HI_SHIFT 4
#define DSC_PPS_RC_RANGE_MINQP_SHIFT 11
#define DSC_PPS_RC_RANGE_MAXQP_SHIFT 6
#define DSC_PPS_NATIVE_420_SHIFT 1
/* Configuration for a single Rate Control model range */
struct drm_dsc_rc_range_parameters {
/* Min Quantization Parameters allowed for this range */
u8 range_min_qp;
/* Max Quantization Parameters allowed for this range */
u8 range_max_qp;
/* Bits/group offset to apply to target for this group */
u8 range_bpg_offset;
};
struct drm_dsc_config {
/* Bits / component for previous reconstructed line buffer */
u8 line_buf_depth;
/* Bits per component to code (must be 8, 10, or 12) */
u8 bits_per_component;
/*
* Flag indicating to do RGB - YCoCg conversion
* and back (should be 1 for RGB input)
*/
bool convert_rgb;
u8 slice_count;
/* Slice Width */
u16 slice_width;
/* Slice Height */
u16 slice_height;
/*
* 4:2:2 enable mode (from PPS, 4:2:2 conversion happens
* outside of DSC encode/decode algorithm)
*/
bool enable422;
/* Picture Width */
u16 pic_width;
/* Picture Height */
u16 pic_height;
/* Offset to bits/group used by RC to determine QP adjustment */
u8 rc_tgt_offset_high;
/* Offset to bits/group used by RC to determine QP adjustment */
u8 rc_tgt_offset_low;
/* Bits/pixel target << 4 (ie., 4 fractional bits) */
u16 bits_per_pixel;
/*
* Factor to determine if an edge is present based
* on the bits produced
*/
u8 rc_edge_factor;
/* Slow down incrementing once the range reaches this value */
u8 rc_quant_incr_limit1;
/* Slow down incrementing once the range reaches this value */
u8 rc_quant_incr_limit0;
/* Number of pixels to delay the initial transmission */
u16 initial_xmit_delay;
/* Number of pixels to delay the VLD on the decoder,not including SSM */
u16 initial_dec_delay;
/* Block prediction enable */
bool block_pred_enable;
/* Bits/group offset to use for first line of the slice */
u8 first_line_bpg_offset;
/* Value to use for RC model offset at slice start */
u16 initial_offset;
/* Thresholds defining each of the buffer ranges */
u16 rc_buf_thresh[DSC_NUM_BUF_RANGES - 1];
/* Parameters for each of the RC ranges */
struct drm_dsc_rc_range_parameters rc_range_params[DSC_NUM_BUF_RANGES];
/* Total size of RC model */
u16 rc_model_size;
/* Minimum QP where flatness information is sent */
u8 flatness_min_qp;
/* Maximum QP where flatness information is sent */
u8 flatness_max_qp;
/* Initial value for scale factor */
u8 initial_scale_value;
/* Decrement scale factor every scale_decrement_interval groups */
u16 scale_decrement_interval;
/* Increment scale factor every scale_increment_interval groups */
u16 scale_increment_interval;
/* Non-first line BPG offset to use */
u16 nfl_bpg_offset;
/* BPG offset used to enforce slice bit */
u16 slice_bpg_offset;
/* Final RC linear transformation offset value */
u16 final_offset;
/* Enable on-off VBR (ie., disable stuffing bits) */
bool vbr_enable;
/* Mux word size (in bits) for SSM mode */
u8 mux_word_size;
/*
* The (max) size in bytes of the "chunks" that are
* used in slice multiplexing
*/
u16 slice_chunk_size;
/* Rate Control buffer siz in bits */
u16 rc_bits;
/* DSC Minor Version */
u8 dsc_version_minor;
/* DSC Major version */
u8 dsc_version_major;
/* Native 4:2:2 support */
bool native_422;
/* Native 4:2:0 support */
bool native_420;
/* Additional bits/grp for seconnd line of slice for native 4:2:0 */
u8 second_line_bpg_offset;
/* Num of bits deallocated for each grp that is not in second line of slice */
u16 nsl_bpg_offset;
/* Offset adj fr second line in Native 4:2:0 mode */
u16 second_line_offset_adj;
};
/**
* struct picture_parameter_set - Represents 128 bytes of Picture Parameter Set
*
* The VESA DSC standard defines picture parameter set (PPS) which display
* stream compression encoders must communicate to decoders.
* The PPS is encapsulated in 128 bytes (PPS 0 through PPS 127). The fields in
* this structure are as per Table 4.1 in Vesa DSC specification v1.1/v1.2.
* The PPS fields that span over more than a byte should be stored in Big Endian
* format.
*/
struct drm_dsc_picture_parameter_set {
/**
* @dsc_version:
* PPS0[3:0] - dsc_version_minor: Contains Minor version of DSC
* PPS0[7:4] - dsc_version_major: Contains major version of DSC
*/
u8 dsc_version;
/**
* @pps_identifier:
* PPS1[7:0] - Application specific identifier that can be
* used to differentiate between different PPS tables.
*/
u8 pps_identifier;
/**
* @pps_reserved:
* PPS2[7:0]- RESERVED Byte
*/
u8 pps_reserved;
/**
* @pps_3:
* PPS3[3:0] - linebuf_depth: Contains linebuffer bit depth used to
* generate the bitstream. (0x0 - 16 bits for DSC 1.2, 0x8 - 8 bits,
* 0xA - 10 bits, 0xB - 11 bits, 0xC - 12 bits, 0xD - 13 bits,
* 0xE - 14 bits for DSC1.2, 0xF - 14 bits for DSC 1.2.
* PPS3[7:4] - bits_per_component: Bits per component for the original
* pixels of the encoded picture.
* 0x0 = 16bpc (allowed only when dsc_version_minor = 0x2)
* 0x8 = 8bpc, 0xA = 10bpc, 0xC = 12bpc, 0xE = 14bpc (also
* allowed only when dsc_minor_version = 0x2)
*/
u8 pps_3;
/**
* @pps_4:
* PPS4[1:0] -These are the most significant 2 bits of
* compressed BPP bits_per_pixel[9:0] syntax element.
* PPS4[2] - vbr_enable: 0 = VBR disabled, 1 = VBR enabled
* PPS4[3] - simple_422: Indicates if decoder drops samples to
* reconstruct the 4:2:2 picture.
* PPS4[4] - Convert_rgb: Indicates if DSC color space conversion is
* active.
* PPS4[5] - blobk_pred_enable: Indicates if BP is used to code any
* groups in picture
* PPS4[7:6] - Reseved bits
*/
u8 pps_4;
/**
* @bits_per_pixel_low:
* PPS5[7:0] - This indicates the lower significant 8 bits of
* the compressed BPP bits_per_pixel[9:0] element.
*/
u8 bits_per_pixel_low;
/**
* @pic_height:
* PPS6[7:0], PPS7[7:0] -pic_height: Specifies the number of pixel rows
* within the raster.
*/
__be16 pic_height;
/**
* @pic_width:
* PPS8[7:0], PPS9[7:0] - pic_width: Number of pixel columns within
* the raster.
*/
__be16 pic_width;
/**
* @slice_height:
* PPS10[7:0], PPS11[7:0] - Slice height in units of pixels.
*/
__be16 slice_height;
/**
* @slice_width:
* PPS12[7:0], PPS13[7:0] - Slice width in terms of pixels.
*/
__be16 slice_width;
/**
* @chunk_size:
* PPS14[7:0], PPS15[7:0] - Size in units of bytes of the chunks
* that are used for slice multiplexing.
*/
__be16 chunk_size;
/**
* @initial_xmit_delay_high:
* PPS16[1:0] - Most Significant two bits of initial transmission delay.
* It specifies the number of pixel times that the encoder waits before
* transmitting data from its rate buffer.
* PPS16[7:2] - Reserved
*/
u8 initial_xmit_delay_high;
/**
* @initial_xmit_delay_low:
* PPS17[7:0] - Least significant 8 bits of initial transmission delay.
*/
u8 initial_xmit_delay_low;
/**
* @initial_dec_delay:
*
* PPS18[7:0], PPS19[7:0] - Initial decoding delay which is the number
* of pixel times that the decoder accumulates data in its rate buffer
* before starting to decode and output pixels.
*/
__be16 initial_dec_delay;
/**
* @pps20_reserved:
*
* PPS20[7:0] - Reserved
*/
u8 pps20_reserved;
/**
* @initial_scale_value:
* PPS21[5:0] - Initial rcXformScale factor used at beginning
* of a slice.
* PPS21[7:6] - Reserved
*/
u8 initial_scale_value;
/**
* @scale_increment_interval:
* PPS22[7:0], PPS23[7:0] - Number of group times between incrementing
* the rcXformScale factor at end of a slice.
*/
__be16 scale_increment_interval;
/**
* @scale_decrement_interval_high:
* PPS24[3:0] - Higher 4 bits indicating number of group times between
* decrementing the rcXformScale factor at beginning of a slice.
* PPS24[7:4] - Reserved
*/
u8 scale_decrement_interval_high;
/**
* @scale_decrement_interval_low:
* PPS25[7:0] - Lower 8 bits of scale decrement interval
*/
u8 scale_decrement_interval_low;
/**
* @pps26_reserved:
* PPS26[7:0]
*/
u8 pps26_reserved;
/**
* @first_line_bpg_offset:
* PPS27[4:0] - Number of additional bits that are allocated
* for each group on first line of a slice.
* PPS27[7:5] - Reserved
*/
u8 first_line_bpg_offset;
/**
* @nfl_bpg_offset:
* PPS28[7:0], PPS29[7:0] - Number of bits including frac bits
* deallocated for each group for groups after the first line of slice.
*/
__be16 nfl_bpg_offset;
/**
* @slice_bpg_offset:
* PPS30, PPS31[7:0] - Number of bits that are deallocated for each
* group to enforce the slice constraint.
*/
__be16 slice_bpg_offset;
/**
* @initial_offset:
* PPS32,33[7:0] - Initial value for rcXformOffset
*/
__be16 initial_offset;
/**
* @final_offset:
* PPS34,35[7:0] - Maximum end-of-slice value for rcXformOffset
*/
__be16 final_offset;
/**
* @flatness_min_qp:
* PPS36[4:0] - Minimum QP at which flatness is signaled and
* flatness QP adjustment is made.
* PPS36[7:5] - Reserved
*/
u8 flatness_min_qp;
/**
* @flatness_max_qp:
* PPS37[4:0] - Max QP at which flatness is signalled and
* the flatness adjustment is made.
* PPS37[7:5] - Reserved
*/
u8 flatness_max_qp;
/**
* @rc_model_size:
* PPS38,39[7:0] - Number of bits within RC Model.
*/
__be16 rc_model_size;
/**
* @rc_edge_factor:
* PPS40[3:0] - Ratio of current activity vs, previous
* activity to determine presence of edge.
* PPS40[7:4] - Reserved
*/
u8 rc_edge_factor;
/**
* @rc_quant_incr_limit0:
* PPS41[4:0] - QP threshold used in short term RC
* PPS41[7:5] - Reserved
*/
u8 rc_quant_incr_limit0;
/**
* @rc_quant_incr_limit1:
* PPS42[4:0] - QP threshold used in short term RC
* PPS42[7:5] - Reserved
*/
u8 rc_quant_incr_limit1;
/**
* @rc_tgt_offset:
* PPS43[3:0] - Lower end of the variability range around the target
* bits per group that is allowed by short term RC.
* PPS43[7:4]- Upper end of the variability range around the target
* bits per group that i allowed by short term rc.
*/
u8 rc_tgt_offset;
/**
* @rc_buf_thresh:
* PPS44[7:0] - PPS57[7:0] - Specifies the thresholds in RC model for
* the 15 ranges defined by 14 thresholds.
*/
u8 rc_buf_thresh[DSC_NUM_BUF_RANGES - 1];
/**
* @rc_range_parameters:
* PPS58[7:0] - PPS87[7:0]
* Parameters that correspond to each of the 15 ranges.
*/
__be16 rc_range_parameters[DSC_NUM_BUF_RANGES];
/**
* @native_422_420:
* PPS88[0] - 0 = Native 4:2:2 not used
* 1 = Native 4:2:2 used
* PPS88[1] - 0 = Native 4:2:0 not use
* 1 = Native 4:2:0 used
* PPS88[7:2] - Reserved 6 bits
*/
u8 native_422_420;
/**
* @second_line_bpg_offset:
* PPS89[4:0] - Additional bits/group budget for the
* second line of a slice in Native 4:2:0 mode.
* Set to 0 if DSC minor version is 1 or native420 is 0.
* PPS89[7:5] - Reserved
*/
u8 second_line_bpg_offset;
/**
* @nsl_bpg_offset:
* PPS90[7:0], PPS91[7:0] - Number of bits that are deallocated
* for each group that is not in the second line of a slice.
*/
__be16 nsl_bpg_offset;
/**
* @second_line_offset_adj:
* PPS92[7:0], PPS93[7:0] - Used as offset adjustment for the second
* line in Native 4:2:0 mode.
*/
__be16 second_line_offset_adj;
/**
* @pps_long_94_reserved:
* PPS 94, 95, 96, 97 - Reserved
*/
u32 pps_long_94_reserved;
/**
* @pps_long_98_reserved:
* PPS 98, 99, 100, 101 - Reserved
*/
u32 pps_long_98_reserved;
/**
* @pps_long_102_reserved:
* PPS 102, 103, 104, 105 - Reserved
*/
u32 pps_long_102_reserved;
/**
* @pps_long_106_reserved:
* PPS 106, 107, 108, 109 - reserved
*/
u32 pps_long_106_reserved;
/**
* @pps_long_110_reserved:
* PPS 110, 111, 112, 113 - reserved
*/
u32 pps_long_110_reserved;
/**
* @pps_long_114_reserved:
* PPS 114 - 117 - reserved
*/
u32 pps_long_114_reserved;
/**
* @pps_long_118_reserved:
* PPS 118 - 121 - reserved
*/
u32 pps_long_118_reserved;
/**
* @pps_long_122_reserved:
* PPS 122- 125 - reserved
*/
u32 pps_long_122_reserved;
/**
* @pps_short_126_reserved:
* PPS 126, 127 - reserved
*/
__be16 pps_short_126_reserved;
} __packed;
/**
* struct drm_dsc_pps_infoframe - DSC infoframe carrying the Picture Parameter
* Set Metadata
*
* This structure represents the DSC PPS infoframe required to send the Picture
* Parameter Set metadata required before enabling VESA Display Stream
* Compression. This is based on the DP Secondary Data Packet structure and
* comprises of SDP Header as defined in drm_dp_helper.h and PPS payload.
*
* @pps_header: Header for PPS as per DP SDP header format
* @pps_payload: PPS payload fields as per DSC specification Table 4-1
*/
struct drm_dsc_pps_infoframe {
struct dp_sdp_header pps_header;
struct drm_dsc_picture_parameter_set pps_payload;
} __packed;
void drm_dsc_dp_pps_header_init(struct drm_dsc_pps_infoframe *pps_sdp);
void drm_dsc_pps_infoframe_pack(struct drm_dsc_pps_infoframe *pps_sdp,
const struct drm_dsc_config *dsc_cfg);
#endif /* _DRM_DSC_H_ */
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