1 /* SPDX-License-Identifier: MIT
2 * Copyright (C) 2018 Intel Corp.
11 #include <drm/display/drm_dp.h>
13 /* VESA Display Stream Compression DSC 1.2 constants */
14 #define DSC_NUM_BUF_RANGES 15
15 #define DSC_MUX_WORD_SIZE_8_10_BPC 48
16 #define DSC_MUX_WORD_SIZE_12_BPC 64
17 #define DSC_RC_PIXELS_PER_GROUP 3
18 #define DSC_SCALE_DECREMENT_INTERVAL_MAX 4095
19 #define DSC_RANGE_BPG_OFFSET_MASK 0x3f
21 /* DSC Rate Control Constants */
22 #define DSC_RC_MODEL_SIZE_CONST 8192
23 #define DSC_RC_EDGE_FACTOR_CONST 6
24 #define DSC_RC_TGT_OFFSET_HI_CONST 3
25 #define DSC_RC_TGT_OFFSET_LO_CONST 3
27 /* DSC PPS constants and macros */
28 #define DSC_PPS_VERSION_MAJOR_SHIFT 4
29 #define DSC_PPS_BPC_SHIFT 4
30 #define DSC_PPS_MSB_SHIFT 8
31 #define DSC_PPS_LSB_MASK (0xFF << 0)
32 #define DSC_PPS_BPP_HIGH_MASK (0x3 << 8)
33 #define DSC_PPS_VBR_EN_SHIFT 2
34 #define DSC_PPS_SIMPLE422_SHIFT 3
35 #define DSC_PPS_CONVERT_RGB_SHIFT 4
36 #define DSC_PPS_BLOCK_PRED_EN_SHIFT 5
37 #define DSC_PPS_INIT_XMIT_DELAY_HIGH_MASK (0x3 << 8)
38 #define DSC_PPS_SCALE_DEC_INT_HIGH_MASK (0xF << 8)
39 #define DSC_PPS_RC_TGT_OFFSET_HI_SHIFT 4
40 #define DSC_PPS_RC_RANGE_MINQP_SHIFT 11
41 #define DSC_PPS_RC_RANGE_MAXQP_SHIFT 6
42 #define DSC_PPS_NATIVE_420_SHIFT 1
45 * struct drm_dsc_rc_range_parameters - DSC Rate Control range parameters
47 * This defines different rate control parameters used by the DSC engine
48 * to compress the frame.
50 struct drm_dsc_rc_range_parameters {
52 * @range_min_qp: Min Quantization Parameters allowed for this range
56 * @range_max_qp: Max Quantization Parameters allowed for this range
61 * Bits/group offset to apply to target for this group
67 * struct drm_dsc_config - Parameters required to configure DSC
69 * Driver populates this structure with all the parameters required
70 * to configure the display stream compression on the source.
72 struct drm_dsc_config {
75 * Bits per component for previous reconstructed line buffer
79 * @bits_per_component: Bits per component to code (8/10/12)
81 u8 bits_per_component;
84 * Flag to indicate if RGB - YCoCg conversion is needed
85 * True if RGB input, False if YCoCg input
89 * @slice_count: Number fo slices per line used by the DSC encoder
93 * @slice_width: Width of each slice in pixels
97 * @slice_height: Slice height in pixels
101 * @simple_422: True if simple 4_2_2 mode is enabled else False
105 * @pic_width: Width of the input display frame in pixels
109 * @pic_height: Vertical height of the input display frame
113 * @rc_tgt_offset_high:
114 * Offset to bits/group used by RC to determine QP adjustment
116 u8 rc_tgt_offset_high;
118 * @rc_tgt_offset_low:
119 * Offset to bits/group used by RC to determine QP adjustment
121 u8 rc_tgt_offset_low;
124 * Target bits per pixel with 4 fractional bits, bits_per_pixel << 4
129 * Factor to determine if an edge is present based on the bits produced
133 * @rc_quant_incr_limit1:
134 * Slow down incrementing once the range reaches this value
136 u8 rc_quant_incr_limit1;
138 * @rc_quant_incr_limit0:
139 * Slow down incrementing once the range reaches this value
141 u8 rc_quant_incr_limit0;
143 * @initial_xmit_delay:
144 * Number of pixels to delay the initial transmission
146 u16 initial_xmit_delay;
148 * @initial_dec_delay:
149 * Initial decoder delay, number of pixel times that the decoder
150 * accumulates data in its rate buffer before starting to decode
153 u16 initial_dec_delay;
155 * @block_pred_enable:
156 * True if block prediction is used to code any groups within the
157 * picture. False if BP not used
159 bool block_pred_enable;
161 * @first_line_bpg_offset:
162 * Number of additional bits allocated for each group on the first
165 u8 first_line_bpg_offset;
167 * @initial_offset: Value to use for RC model offset at slice start
171 * @rc_buf_thresh: Thresholds defining each of the buffer ranges
173 u16 rc_buf_thresh[DSC_NUM_BUF_RANGES - 1];
176 * Parameters for each of the RC ranges defined in
177 * &struct drm_dsc_rc_range_parameters
179 struct drm_dsc_rc_range_parameters rc_range_params[DSC_NUM_BUF_RANGES];
181 * @rc_model_size: Total size of RC model
185 * @flatness_min_qp: Minimum QP where flatness information is sent
189 * @flatness_max_qp: Maximum QP where flatness information is sent
193 * @initial_scale_value: Initial value for the scale factor
195 u8 initial_scale_value;
197 * @scale_decrement_interval:
198 * Specifies number of group times between decrementing the scale factor
199 * at beginning of a slice.
201 u16 scale_decrement_interval;
203 * @scale_increment_interval:
204 * Number of group times between incrementing the scale factor value
205 * used at the beginning of a slice.
207 u16 scale_increment_interval;
209 * @nfl_bpg_offset: Non first line BPG offset to be used
213 * @slice_bpg_offset: BPG offset used to enforce slice bit
215 u16 slice_bpg_offset;
217 * @final_offset: Final RC linear transformation offset value
221 * @vbr_enable: True if VBR mode is enabled, false if disabled
225 * @mux_word_size: Mux word size (in bits) for SSM mode
230 * The (max) size in bytes of the "chunks" that are used in slice
233 u16 slice_chunk_size;
235 * @rc_bits: Rate control buffer size in bits
239 * @dsc_version_minor: DSC minor version
241 u8 dsc_version_minor;
243 * @dsc_version_major: DSC major version
245 u8 dsc_version_major;
247 * @native_422: True if Native 4:2:2 supported, else false
251 * @native_420: True if Native 4:2:0 supported else false.
255 * @second_line_bpg_offset:
256 * Additional bits/grp for seconnd line of slice for native 4:2:0
258 u8 second_line_bpg_offset;
261 * Num of bits deallocated for each grp that is not in second line of
266 * @second_line_offset_adj:
267 * Offset adjustment for second line in Native 4:2:0 mode
269 u16 second_line_offset_adj;
273 * struct drm_dsc_picture_parameter_set - Represents 128 bytes of
274 * Picture Parameter Set
276 * The VESA DSC standard defines picture parameter set (PPS) which display
277 * stream compression encoders must communicate to decoders.
278 * The PPS is encapsulated in 128 bytes (PPS 0 through PPS 127). The fields in
279 * this structure are as per Table 4.1 in Vesa DSC specification v1.1/v1.2.
280 * The PPS fields that span over more than a byte should be stored in Big Endian
283 struct drm_dsc_picture_parameter_set {
286 * PPS0[3:0] - dsc_version_minor: Contains Minor version of DSC
287 * PPS0[7:4] - dsc_version_major: Contains major version of DSC
292 * PPS1[7:0] - Application specific identifier that can be
293 * used to differentiate between different PPS tables.
298 * PPS2[7:0]- RESERVED Byte
303 * PPS3[3:0] - linebuf_depth: Contains linebuffer bit depth used to
304 * generate the bitstream. (0x0 - 16 bits for DSC 1.2, 0x8 - 8 bits,
305 * 0xA - 10 bits, 0xB - 11 bits, 0xC - 12 bits, 0xD - 13 bits,
306 * 0xE - 14 bits for DSC1.2, 0xF - 14 bits for DSC 1.2.
307 * PPS3[7:4] - bits_per_component: Bits per component for the original
308 * pixels of the encoded picture.
309 * 0x0 = 16bpc (allowed only when dsc_version_minor = 0x2)
310 * 0x8 = 8bpc, 0xA = 10bpc, 0xC = 12bpc, 0xE = 14bpc (also
311 * allowed only when dsc_minor_version = 0x2)
316 * PPS4[1:0] -These are the most significant 2 bits of
317 * compressed BPP bits_per_pixel[9:0] syntax element.
318 * PPS4[2] - vbr_enable: 0 = VBR disabled, 1 = VBR enabled
319 * PPS4[3] - simple_422: Indicates if decoder drops samples to
320 * reconstruct the 4:2:2 picture.
321 * PPS4[4] - Convert_rgb: Indicates if DSC color space conversion is
323 * PPS4[5] - blobk_pred_enable: Indicates if BP is used to code any
325 * PPS4[7:6] - Reseved bits
329 * @bits_per_pixel_low:
330 * PPS5[7:0] - This indicates the lower significant 8 bits of
331 * the compressed BPP bits_per_pixel[9:0] element.
333 u8 bits_per_pixel_low;
336 * PPS6[7:0], PPS7[7:0] -pic_height: Specifies the number of pixel rows
342 * PPS8[7:0], PPS9[7:0] - pic_width: Number of pixel columns within
348 * PPS10[7:0], PPS11[7:0] - Slice height in units of pixels.
353 * PPS12[7:0], PPS13[7:0] - Slice width in terms of pixels.
358 * PPS14[7:0], PPS15[7:0] - Size in units of bytes of the chunks
359 * that are used for slice multiplexing.
363 * @initial_xmit_delay_high:
364 * PPS16[1:0] - Most Significant two bits of initial transmission delay.
365 * It specifies the number of pixel times that the encoder waits before
366 * transmitting data from its rate buffer.
367 * PPS16[7:2] - Reserved
369 u8 initial_xmit_delay_high;
371 * @initial_xmit_delay_low:
372 * PPS17[7:0] - Least significant 8 bits of initial transmission delay.
374 u8 initial_xmit_delay_low;
376 * @initial_dec_delay:
378 * PPS18[7:0], PPS19[7:0] - Initial decoding delay which is the number
379 * of pixel times that the decoder accumulates data in its rate buffer
380 * before starting to decode and output pixels.
382 __be16 initial_dec_delay;
386 * PPS20[7:0] - Reserved
390 * @initial_scale_value:
391 * PPS21[5:0] - Initial rcXformScale factor used at beginning
393 * PPS21[7:6] - Reserved
395 u8 initial_scale_value;
397 * @scale_increment_interval:
398 * PPS22[7:0], PPS23[7:0] - Number of group times between incrementing
399 * the rcXformScale factor at end of a slice.
401 __be16 scale_increment_interval;
403 * @scale_decrement_interval_high:
404 * PPS24[3:0] - Higher 4 bits indicating number of group times between
405 * decrementing the rcXformScale factor at beginning of a slice.
406 * PPS24[7:4] - Reserved
408 u8 scale_decrement_interval_high;
410 * @scale_decrement_interval_low:
411 * PPS25[7:0] - Lower 8 bits of scale decrement interval
413 u8 scale_decrement_interval_low;
420 * @first_line_bpg_offset:
421 * PPS27[4:0] - Number of additional bits that are allocated
422 * for each group on first line of a slice.
423 * PPS27[7:5] - Reserved
425 u8 first_line_bpg_offset;
428 * PPS28[7:0], PPS29[7:0] - Number of bits including frac bits
429 * deallocated for each group for groups after the first line of slice.
431 __be16 nfl_bpg_offset;
434 * PPS30, PPS31[7:0] - Number of bits that are deallocated for each
435 * group to enforce the slice constraint.
437 __be16 slice_bpg_offset;
440 * PPS32,33[7:0] - Initial value for rcXformOffset
442 __be16 initial_offset;
445 * PPS34,35[7:0] - Maximum end-of-slice value for rcXformOffset
450 * PPS36[4:0] - Minimum QP at which flatness is signaled and
451 * flatness QP adjustment is made.
452 * PPS36[7:5] - Reserved
457 * PPS37[4:0] - Max QP at which flatness is signalled and
458 * the flatness adjustment is made.
459 * PPS37[7:5] - Reserved
464 * PPS38,39[7:0] - Number of bits within RC Model.
466 __be16 rc_model_size;
469 * PPS40[3:0] - Ratio of current activity vs, previous
470 * activity to determine presence of edge.
471 * PPS40[7:4] - Reserved
475 * @rc_quant_incr_limit0:
476 * PPS41[4:0] - QP threshold used in short term RC
477 * PPS41[7:5] - Reserved
479 u8 rc_quant_incr_limit0;
481 * @rc_quant_incr_limit1:
482 * PPS42[4:0] - QP threshold used in short term RC
483 * PPS42[7:5] - Reserved
485 u8 rc_quant_incr_limit1;
488 * PPS43[3:0] - Lower end of the variability range around the target
489 * bits per group that is allowed by short term RC.
490 * PPS43[7:4]- Upper end of the variability range around the target
491 * bits per group that i allowed by short term rc.
496 * PPS44[7:0] - PPS57[7:0] - Specifies the thresholds in RC model for
497 * the 15 ranges defined by 14 thresholds.
499 u8 rc_buf_thresh[DSC_NUM_BUF_RANGES - 1];
501 * @rc_range_parameters:
502 * PPS58[7:0] - PPS87[7:0]
503 * Parameters that correspond to each of the 15 ranges.
505 __be16 rc_range_parameters[DSC_NUM_BUF_RANGES];
508 * PPS88[0] - 0 = Native 4:2:2 not used
509 * 1 = Native 4:2:2 used
510 * PPS88[1] - 0 = Native 4:2:0 not use
511 * 1 = Native 4:2:0 used
512 * PPS88[7:2] - Reserved 6 bits
516 * @second_line_bpg_offset:
517 * PPS89[4:0] - Additional bits/group budget for the
518 * second line of a slice in Native 4:2:0 mode.
519 * Set to 0 if DSC minor version is 1 or native420 is 0.
520 * PPS89[7:5] - Reserved
522 u8 second_line_bpg_offset;
525 * PPS90[7:0], PPS91[7:0] - Number of bits that are deallocated
526 * for each group that is not in the second line of a slice.
528 __be16 nsl_bpg_offset;
530 * @second_line_offset_adj:
531 * PPS92[7:0], PPS93[7:0] - Used as offset adjustment for the second
532 * line in Native 4:2:0 mode.
534 __be16 second_line_offset_adj;
536 * @pps_long_94_reserved:
537 * PPS 94, 95, 96, 97 - Reserved
539 u32 pps_long_94_reserved;
541 * @pps_long_98_reserved:
542 * PPS 98, 99, 100, 101 - Reserved
544 u32 pps_long_98_reserved;
546 * @pps_long_102_reserved:
547 * PPS 102, 103, 104, 105 - Reserved
549 u32 pps_long_102_reserved;
551 * @pps_long_106_reserved:
552 * PPS 106, 107, 108, 109 - reserved
554 u32 pps_long_106_reserved;
556 * @pps_long_110_reserved:
557 * PPS 110, 111, 112, 113 - reserved
559 u32 pps_long_110_reserved;
561 * @pps_long_114_reserved:
562 * PPS 114 - 117 - reserved
564 u32 pps_long_114_reserved;
566 * @pps_long_118_reserved:
567 * PPS 118 - 121 - reserved
569 u32 pps_long_118_reserved;
571 * @pps_long_122_reserved:
572 * PPS 122- 125 - reserved
574 u32 pps_long_122_reserved;
576 * @pps_short_126_reserved:
577 * PPS 126, 127 - reserved
579 __be16 pps_short_126_reserved;
583 * struct drm_dsc_pps_infoframe - DSC infoframe carrying the Picture Parameter
586 * This structure represents the DSC PPS infoframe required to send the Picture
587 * Parameter Set metadata required before enabling VESA Display Stream
588 * Compression. This is based on the DP Secondary Data Packet structure and
589 * comprises of SDP Header as defined &struct dp_sdp_header in drm_dp_helper.h
590 * and PPS payload defined in &struct drm_dsc_picture_parameter_set.
592 * @pps_header: Header for PPS as per DP SDP header format of type
593 * &struct dp_sdp_header
594 * @pps_payload: PPS payload fields as per DSC specification Table 4-1
595 * as represented in &struct drm_dsc_picture_parameter_set
597 struct drm_dsc_pps_infoframe {
598 struct dp_sdp_header pps_header;
599 struct drm_dsc_picture_parameter_set pps_payload;
602 #endif /* _DRM_DSC_H_ */