1 /*
2  * Copyright 2018 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: AMD
23  *
24  */
25 
26 #include "mod_info_packet.h"
27 #include "core_types.h"
28 #include "dc_types.h"
29 #include "mod_shared.h"
30 #include "mod_freesync.h"
31 #include "dc.h"
32 
33 enum vsc_packet_revision {
34 	vsc_packet_undefined = 0,
35 	//01h = VSC SDP supports only 3D stereo.
36 	vsc_packet_rev1 = 1,
37 	//02h = 3D stereo + PSR.
38 	vsc_packet_rev2 = 2,
39 	//03h = 3D stereo + PSR2.
40 	vsc_packet_rev3 = 3,
41 	//04h = 3D stereo + PSR/PSR2 + Y-coordinate.
42 	vsc_packet_rev4 = 4,
43 	//05h = 3D stereo + PSR/PSR2 + Y-coordinate + Pixel Encoding/Colorimetry Format
44 	vsc_packet_rev5 = 5,
45 };
46 
47 #define HDMI_INFOFRAME_TYPE_VENDOR 0x81
48 #define HF_VSIF_VERSION 1
49 
50 // VTEM Byte Offset
51 #define VTEM_PB0		0
52 #define VTEM_PB1		1
53 #define VTEM_PB2		2
54 #define VTEM_PB3		3
55 #define VTEM_PB4		4
56 #define VTEM_PB5		5
57 #define VTEM_PB6		6
58 
59 #define VTEM_MD0		7
60 #define VTEM_MD1		8
61 #define VTEM_MD2		9
62 #define VTEM_MD3		10
63 
64 
65 // VTEM Byte Masks
66 //PB0
67 #define MASK_VTEM_PB0__RESERVED0  0x01
68 #define MASK_VTEM_PB0__SYNC       0x02
69 #define MASK_VTEM_PB0__VFR        0x04
70 #define MASK_VTEM_PB0__AFR        0x08
71 #define MASK_VTEM_PB0__DS_TYPE    0x30
72 	//0: Periodic pseudo-static EM Data Set
73 	//1: Periodic dynamic EM Data Set
74 	//2: Unique EM Data Set
75 	//3: Reserved
76 #define MASK_VTEM_PB0__END        0x40
77 #define MASK_VTEM_PB0__NEW        0x80
78 
79 //PB1
80 #define MASK_VTEM_PB1__RESERVED1 0xFF
81 
82 //PB2
83 #define MASK_VTEM_PB2__ORGANIZATION_ID 0xFF
84 	//0: This is a Vendor Specific EM Data Set
85 	//1: This EM Data Set is defined by This Specification (HDMI 2.1 r102.clean)
86 	//2: This EM Data Set is defined by CTA-861-G
87 	//3: This EM Data Set is defined by VESA
88 //PB3
89 #define MASK_VTEM_PB3__DATA_SET_TAG_MSB    0xFF
90 //PB4
91 #define MASK_VTEM_PB4__DATA_SET_TAG_LSB    0xFF
92 //PB5
93 #define MASK_VTEM_PB5__DATA_SET_LENGTH_MSB 0xFF
94 //PB6
95 #define MASK_VTEM_PB6__DATA_SET_LENGTH_LSB 0xFF
96 
97 
98 
99 //PB7-27 (20 bytes):
100 //PB7 = MD0
101 #define MASK_VTEM_MD0__VRR_EN         0x01
102 #define MASK_VTEM_MD0__M_CONST        0x02
103 #define MASK_VTEM_MD0__RESERVED2      0x0C
104 #define MASK_VTEM_MD0__FVA_FACTOR_M1  0xF0
105 
106 //MD1
107 #define MASK_VTEM_MD1__BASE_VFRONT    0xFF
108 
109 //MD2
110 #define MASK_VTEM_MD2__BASE_REFRESH_RATE_98  0x03
111 #define MASK_VTEM_MD2__RB                    0x04
112 #define MASK_VTEM_MD2__RESERVED3             0xF8
113 
114 //MD3
115 #define MASK_VTEM_MD3__BASE_REFRESH_RATE_07  0xFF
116 
117 enum ColorimetryRGBDP {
118 	ColorimetryRGB_DP_sRGB               = 0,
119 	ColorimetryRGB_DP_AdobeRGB           = 3,
120 	ColorimetryRGB_DP_P3                 = 4,
121 	ColorimetryRGB_DP_CustomColorProfile = 5,
122 	ColorimetryRGB_DP_ITU_R_BT2020RGB    = 6,
123 };
124 enum ColorimetryYCCDP {
125 	ColorimetryYCC_DP_ITU601        = 0,
126 	ColorimetryYCC_DP_ITU709        = 1,
127 	ColorimetryYCC_DP_AdobeYCC      = 5,
128 	ColorimetryYCC_DP_ITU2020YCC    = 6,
129 	ColorimetryYCC_DP_ITU2020YCbCr  = 7,
130 };
131 
132 void mod_build_vsc_infopacket(const struct dc_stream_state *stream,
133 		struct dc_info_packet *info_packet,
134 		bool *use_vsc_sdp_for_colorimetry)
135 {
136 	unsigned int vsc_packet_revision = vsc_packet_undefined;
137 	unsigned int i;
138 	unsigned int pixelEncoding = 0;
139 	unsigned int colorimetryFormat = 0;
140 	bool stereo3dSupport = false;
141 
142 	/* Initialize first, later if infopacket is valid determine if VSC SDP
143 	 * should be used to signal colorimetry format and pixel encoding.
144 	 */
145 	*use_vsc_sdp_for_colorimetry = false;
146 
147 	if (stream->timing.timing_3d_format != TIMING_3D_FORMAT_NONE && stream->view_format != VIEW_3D_FORMAT_NONE) {
148 		vsc_packet_revision = vsc_packet_rev1;
149 		stereo3dSupport = true;
150 	}
151 
152 	/*VSC packet set to 2 when DP revision >= 1.2*/
153 	if (stream->psr_version != 0)
154 		vsc_packet_revision = vsc_packet_rev2;
155 
156 	/* Update to revision 5 for extended colorimetry support for DPCD 1.4+ */
157 	if (stream->link->dpcd_caps.dpcd_rev.raw >= 0x14 &&
158 			stream->link->dpcd_caps.dprx_feature.bits.VSC_SDP_COLORIMETRY_SUPPORTED)
159 		vsc_packet_revision = vsc_packet_rev5;
160 
161 	/* VSC packet not needed based on the features
162 	 * supported by this DP display
163 	 */
164 	if (vsc_packet_revision == vsc_packet_undefined)
165 		return;
166 
167 	if (vsc_packet_revision == vsc_packet_rev2) {
168 		/* Secondary-data Packet ID = 0*/
169 		info_packet->hb0 = 0x00;
170 		/* 07h - Packet Type Value indicating Video
171 		 * Stream Configuration packet
172 		 */
173 		info_packet->hb1 = 0x07;
174 		/* 02h = VSC SDP supporting 3D stereo and PSR
175 		 * (applies to eDP v1.3 or higher).
176 		 */
177 		info_packet->hb2 = 0x02;
178 		/* 08h = VSC packet supporting 3D stereo + PSR
179 		 * (HB2 = 02h).
180 		 */
181 		info_packet->hb3 = 0x08;
182 
183 		for (i = 0; i < 28; i++)
184 			info_packet->sb[i] = 0;
185 
186 		info_packet->valid = true;
187 	}
188 
189 	if (vsc_packet_revision == vsc_packet_rev1) {
190 
191 		info_packet->hb0 = 0x00;	// Secondary-data Packet ID = 0
192 		info_packet->hb1 = 0x07;	// 07h = Packet Type Value indicating Video Stream Configuration packet
193 		info_packet->hb2 = 0x01;	// 01h = Revision number. VSC SDP supporting 3D stereo only
194 		info_packet->hb3 = 0x01;	// 01h = VSC SDP supporting 3D stereo only (HB2 = 01h).
195 
196 		info_packet->valid = true;
197 	}
198 
199 	if (stereo3dSupport) {
200 		/* ==============================================================================================================|
201 		 * A. STEREO 3D
202 		 * ==============================================================================================================|
203 		 * VSC Payload (1 byte) From DP1.2 spec
204 		 *
205 		 * Bits 3:0 (Stereo Interface Method Code)  |  Bits 7:4 (Stereo Interface Method Specific Parameter)
206 		 * -----------------------------------------------------------------------------------------------------
207 		 * 0 = Non Stereo Video                     |  Must be set to 0x0
208 		 * -----------------------------------------------------------------------------------------------------
209 		 * 1 = Frame/Field Sequential               |  0x0: L + R view indication based on MISC1 bit 2:1
210 		 *                                          |  0x1: Right when Stereo Signal = 1
211 		 *                                          |  0x2: Left when Stereo Signal = 1
212 		 *                                          |  (others reserved)
213 		 * -----------------------------------------------------------------------------------------------------
214 		 * 2 = Stacked Frame                        |  0x0: Left view is on top and right view on bottom
215 		 *                                          |  (others reserved)
216 		 * -----------------------------------------------------------------------------------------------------
217 		 * 3 = Pixel Interleaved                    |  0x0: horiz interleaved, right view pixels on even lines
218 		 *                                          |  0x1: horiz interleaved, right view pixels on odd lines
219 		 *                                          |  0x2: checker board, start with left view pixel
220 		 *                                          |  0x3: vertical interleaved, start with left view pixels
221 		 *                                          |  0x4: vertical interleaved, start with right view pixels
222 		 *                                          |  (others reserved)
223 		 * -----------------------------------------------------------------------------------------------------
224 		 * 4 = Side-by-side                         |  0x0: left half represents left eye view
225 		 *                                          |  0x1: left half represents right eye view
226 		 */
227 		switch (stream->timing.timing_3d_format) {
228 		case TIMING_3D_FORMAT_HW_FRAME_PACKING:
229 		case TIMING_3D_FORMAT_SW_FRAME_PACKING:
230 		case TIMING_3D_FORMAT_TOP_AND_BOTTOM:
231 		case TIMING_3D_FORMAT_TB_SW_PACKED:
232 			info_packet->sb[0] = 0x02; // Stacked Frame, Left view is on top and right view on bottom.
233 			break;
234 		case TIMING_3D_FORMAT_DP_HDMI_INBAND_FA:
235 		case TIMING_3D_FORMAT_INBAND_FA:
236 			info_packet->sb[0] = 0x01; // Frame/Field Sequential, L + R view indication based on MISC1 bit 2:1
237 			break;
238 		case TIMING_3D_FORMAT_SIDE_BY_SIDE:
239 		case TIMING_3D_FORMAT_SBS_SW_PACKED:
240 			info_packet->sb[0] = 0x04; // Side-by-side
241 			break;
242 		default:
243 			info_packet->sb[0] = 0x00; // No Stereo Video, Shall be cleared to 0x0.
244 			break;
245 		}
246 
247 	}
248 
249 	/* 05h = VSC SDP supporting 3D stereo, PSR2, and Pixel Encoding/Colorimetry Format indication.
250 	 *   Added in DP1.3, a DP Source device is allowed to indicate the pixel encoding/colorimetry
251 	 *   format to the DP Sink device with VSC SDP only when the DP Sink device supports it
252 	 *   (i.e., VSC_SDP_EXTENSION_FOR_COLORIMETRY_SUPPORTED bit in the DPRX_FEATURE_ENUMERATION_LIST
253 	 *   register (DPCD Address 02210h, bit 3) is set to 1).
254 	 *   (Requires VSC_SDP_EXTENSION_FOR_COLORIMETRY_SUPPORTED bit set to 1 in DPCD 02210h. This
255 	 *   DPCD register is exposed in the new Extended Receiver Capability field for DPCD Rev. 1.4
256 	 *   (and higher). When MISC1. bit 6. is Set to 1, a Source device uses a VSC SDP to indicate
257 	 *   the Pixel Encoding/Colorimetry Format and that a Sink device must ignore MISC1, bit 7, and
258 	 *   MISC0, bits 7:1 (MISC1, bit 7. and MISC0, bits 7:1 become "don't care").)
259 	 */
260 	if (vsc_packet_revision == vsc_packet_rev5) {
261 		/* Secondary-data Packet ID = 0 */
262 		info_packet->hb0 = 0x00;
263 		/* 07h - Packet Type Value indicating Video Stream Configuration packet */
264 		info_packet->hb1 = 0x07;
265 		/* 05h = VSC SDP supporting 3D stereo, PSR2, and Pixel Encoding/Colorimetry Format indication. */
266 		info_packet->hb2 = 0x05;
267 		/* 13h = VSC SDP supporting 3D stereo, + PSR2, + Pixel Encoding/Colorimetry Format indication (HB2 = 05h). */
268 		info_packet->hb3 = 0x13;
269 
270 		info_packet->valid = true;
271 
272 		/* If we are using VSC SDP revision 05h, use this to signal for
273 		 * colorimetry format and pixel encoding. HW should later be
274 		 * programmed to set MSA MISC1 bit 6 to indicate ignore
275 		 * colorimetry format and pixel encoding in the MSA.
276 		 */
277 		*use_vsc_sdp_for_colorimetry = true;
278 
279 		/* Set VSC SDP fields for pixel encoding and colorimetry format from DP 1.3 specs
280 		 * Data Bytes DB 18~16
281 		 * Bits 3:0 (Colorimetry Format)        |  Bits 7:4 (Pixel Encoding)
282 		 * ----------------------------------------------------------------------------------------------------
283 		 * 0x0 = sRGB                           |  0 = RGB
284 		 * 0x1 = RGB Wide Gamut Fixed Point
285 		 * 0x2 = RGB Wide Gamut Floating Point
286 		 * 0x3 = AdobeRGB
287 		 * 0x4 = DCI-P3
288 		 * 0x5 = CustomColorProfile
289 		 * (others reserved)
290 		 * ----------------------------------------------------------------------------------------------------
291 		 * 0x0 = ITU-R BT.601                   |  1 = YCbCr444
292 		 * 0x1 = ITU-R BT.709
293 		 * 0x2 = xvYCC601
294 		 * 0x3 = xvYCC709
295 		 * 0x4 = sYCC601
296 		 * 0x5 = AdobeYCC601
297 		 * 0x6 = ITU-R BT.2020 Y'cC'bcC'rc
298 		 * 0x7 = ITU-R BT.2020 Y'C'bC'r
299 		 * (others reserved)
300 		 * ----------------------------------------------------------------------------------------------------
301 		 * 0x0 = ITU-R BT.601                   |  2 = YCbCr422
302 		 * 0x1 = ITU-R BT.709
303 		 * 0x2 = xvYCC601
304 		 * 0x3 = xvYCC709
305 		 * 0x4 = sYCC601
306 		 * 0x5 = AdobeYCC601
307 		 * 0x6 = ITU-R BT.2020 Y'cC'bcC'rc
308 		 * 0x7 = ITU-R BT.2020 Y'C'bC'r
309 		 * (others reserved)
310 		 * ----------------------------------------------------------------------------------------------------
311 		 * 0x0 = ITU-R BT.601                   |  3 = YCbCr420
312 		 * 0x1 = ITU-R BT.709
313 		 * 0x2 = xvYCC601
314 		 * 0x3 = xvYCC709
315 		 * 0x4 = sYCC601
316 		 * 0x5 = AdobeYCC601
317 		 * 0x6 = ITU-R BT.2020 Y'cC'bcC'rc
318 		 * 0x7 = ITU-R BT.2020 Y'C'bC'r
319 		 * (others reserved)
320 		 * ----------------------------------------------------------------------------------------------------
321 		 * 0x0 =DICOM Part14 Grayscale          |  4 = Yonly
322 		 * Display Function
323 		 * (others reserved)
324 		 */
325 
326 		/* Set Pixel Encoding */
327 		switch (stream->timing.pixel_encoding) {
328 		case PIXEL_ENCODING_RGB:
329 			pixelEncoding = 0x0;  /* RGB = 0h */
330 			break;
331 		case PIXEL_ENCODING_YCBCR444:
332 			pixelEncoding = 0x1;  /* YCbCr444 = 1h */
333 			break;
334 		case PIXEL_ENCODING_YCBCR422:
335 			pixelEncoding = 0x2;  /* YCbCr422 = 2h */
336 			break;
337 		case PIXEL_ENCODING_YCBCR420:
338 			pixelEncoding = 0x3;  /* YCbCr420 = 3h */
339 			break;
340 		default:
341 			pixelEncoding = 0x0;  /* default RGB = 0h */
342 			break;
343 		}
344 
345 		/* Set Colorimetry format based on pixel encoding */
346 		switch (stream->timing.pixel_encoding) {
347 		case PIXEL_ENCODING_RGB:
348 			if ((stream->output_color_space == COLOR_SPACE_SRGB) ||
349 					(stream->output_color_space == COLOR_SPACE_SRGB_LIMITED))
350 				colorimetryFormat = ColorimetryRGB_DP_sRGB;
351 			else if (stream->output_color_space == COLOR_SPACE_ADOBERGB)
352 				colorimetryFormat = ColorimetryRGB_DP_AdobeRGB;
353 			else if ((stream->output_color_space == COLOR_SPACE_2020_RGB_FULLRANGE) ||
354 					(stream->output_color_space == COLOR_SPACE_2020_RGB_LIMITEDRANGE))
355 				colorimetryFormat = ColorimetryRGB_DP_ITU_R_BT2020RGB;
356 			break;
357 
358 		case PIXEL_ENCODING_YCBCR444:
359 		case PIXEL_ENCODING_YCBCR422:
360 		case PIXEL_ENCODING_YCBCR420:
361 			/* Note: xvYCC probably not supported correctly here on DP since colorspace translation
362 			 * loses distinction between BT601 vs xvYCC601 in translation
363 			 */
364 			if (stream->output_color_space == COLOR_SPACE_YCBCR601)
365 				colorimetryFormat = ColorimetryYCC_DP_ITU601;
366 			else if (stream->output_color_space == COLOR_SPACE_YCBCR709)
367 				colorimetryFormat = ColorimetryYCC_DP_ITU709;
368 			else if (stream->output_color_space == COLOR_SPACE_ADOBERGB)
369 				colorimetryFormat = ColorimetryYCC_DP_AdobeYCC;
370 			else if (stream->output_color_space == COLOR_SPACE_2020_YCBCR)
371 				colorimetryFormat = ColorimetryYCC_DP_ITU2020YCbCr;
372 			break;
373 
374 		default:
375 			colorimetryFormat = ColorimetryRGB_DP_sRGB;
376 			break;
377 		}
378 
379 		info_packet->sb[16] = (pixelEncoding << 4) | colorimetryFormat;
380 
381 		/* Set color depth */
382 		switch (stream->timing.display_color_depth) {
383 		case COLOR_DEPTH_666:
384 			/* NOTE: This is actually not valid for YCbCr pixel encoding to have 6 bpc
385 			 *       as of DP1.4 spec, but value of 0 probably reserved here for potential future use.
386 			 */
387 			info_packet->sb[17] = 0;
388 			break;
389 		case COLOR_DEPTH_888:
390 			info_packet->sb[17] = 1;
391 			break;
392 		case COLOR_DEPTH_101010:
393 			info_packet->sb[17] = 2;
394 			break;
395 		case COLOR_DEPTH_121212:
396 			info_packet->sb[17] = 3;
397 			break;
398 		/*case COLOR_DEPTH_141414: -- NO SUCH FORMAT IN DP SPEC */
399 		case COLOR_DEPTH_161616:
400 			info_packet->sb[17] = 4;
401 			break;
402 		default:
403 			info_packet->sb[17] = 0;
404 			break;
405 		}
406 
407 		/* all YCbCr are always limited range */
408 		if ((stream->output_color_space == COLOR_SPACE_SRGB_LIMITED) ||
409 				(stream->output_color_space == COLOR_SPACE_2020_RGB_LIMITEDRANGE) ||
410 				(pixelEncoding != 0x0)) {
411 			info_packet->sb[17] |= 0x80; /* DB17 bit 7 set to 1 for CEA timing. */
412 		}
413 
414 		/* Content Type (Bits 2:0)
415 		 *  0 = Not defined.
416 		 *  1 = Graphics.
417 		 *  2 = Photo.
418 		 *  3 = Video.
419 		 *  4 = Game.
420 		 */
421 		info_packet->sb[18] = 0;
422 	}
423 }
424 
425 /**
426  *****************************************************************************
427  *  Function: mod_build_hf_vsif_infopacket
428  *
429  *  @brief
430  *     Prepare HDMI Vendor Specific info frame.
431  *     Follows HDMI Spec to build up Vendor Specific info frame
432  *
433  *  @param [in] stream: contains data we may need to construct VSIF (i.e. timing_3d_format, etc.)
434  *  @param [out] info_packet:   output structure where to store VSIF
435  *****************************************************************************
436  */
437 void mod_build_hf_vsif_infopacket(const struct dc_stream_state *stream,
438 		struct dc_info_packet *info_packet, int ALLMEnabled, int ALLMValue)
439 {
440 		unsigned int length = 5;
441 		bool hdmi_vic_mode = false;
442 		uint8_t checksum = 0;
443 		uint32_t i = 0;
444 		enum dc_timing_3d_format format;
445 		bool bALLM = (bool)ALLMEnabled;
446 		bool bALLMVal = (bool)ALLMValue;
447 
448 		info_packet->valid = false;
449 		format = stream->timing.timing_3d_format;
450 		if (stream->view_format == VIEW_3D_FORMAT_NONE)
451 			format = TIMING_3D_FORMAT_NONE;
452 
453 		if (stream->timing.hdmi_vic != 0
454 				&& stream->timing.h_total >= 3840
455 				&& stream->timing.v_total >= 2160
456 				&& format == TIMING_3D_FORMAT_NONE)
457 			hdmi_vic_mode = true;
458 
459 		if ((format == TIMING_3D_FORMAT_NONE) && !hdmi_vic_mode && !bALLM)
460 			return;
461 
462 		info_packet->sb[1] = 0x03;
463 		info_packet->sb[2] = 0x0C;
464 		info_packet->sb[3] = 0x00;
465 
466 		if (bALLM) {
467 			info_packet->sb[1] = 0xD8;
468 			info_packet->sb[2] = 0x5D;
469 			info_packet->sb[3] = 0xC4;
470 			info_packet->sb[4] = HF_VSIF_VERSION;
471 		}
472 
473 		if (format != TIMING_3D_FORMAT_NONE)
474 			info_packet->sb[4] = (2 << 5);
475 
476 		else if (hdmi_vic_mode)
477 			info_packet->sb[4] = (1 << 5);
478 
479 		switch (format) {
480 		case TIMING_3D_FORMAT_HW_FRAME_PACKING:
481 		case TIMING_3D_FORMAT_SW_FRAME_PACKING:
482 			info_packet->sb[5] = (0x0 << 4);
483 			break;
484 
485 		case TIMING_3D_FORMAT_SIDE_BY_SIDE:
486 		case TIMING_3D_FORMAT_SBS_SW_PACKED:
487 			info_packet->sb[5] = (0x8 << 4);
488 			length = 6;
489 			break;
490 
491 		case TIMING_3D_FORMAT_TOP_AND_BOTTOM:
492 		case TIMING_3D_FORMAT_TB_SW_PACKED:
493 			info_packet->sb[5] = (0x6 << 4);
494 			break;
495 
496 		default:
497 			break;
498 		}
499 
500 		if (hdmi_vic_mode)
501 			info_packet->sb[5] = stream->timing.hdmi_vic;
502 
503 		info_packet->hb0 = HDMI_INFOFRAME_TYPE_VENDOR;
504 		info_packet->hb1 = 0x01;
505 		info_packet->hb2 = (uint8_t) (length);
506 
507 		if (bALLM)
508 			info_packet->sb[5] = (info_packet->sb[5] & ~0x02) | (bALLMVal << 1);
509 
510 		checksum += info_packet->hb0;
511 		checksum += info_packet->hb1;
512 		checksum += info_packet->hb2;
513 
514 		for (i = 1; i <= length; i++)
515 			checksum += info_packet->sb[i];
516 
517 		info_packet->sb[0] = (uint8_t) (0x100 - checksum);
518 
519 		info_packet->valid = true;
520 }
521 
522