xref: /aosp_15_r20/external/igt-gpu-tools/lib/tests/igt_edid.c (revision d83cc019efdc2edc6c4b16e9034a3ceb8d35d77c)
1 /*
2  * Copyright © 2019 Intel Corporation
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 (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  * Authors: Simon Ser <[email protected]>
24  */
25 
26 #include "config.h"
27 
28 #include <stdbool.h>
29 
30 #include "igt_core.h"
31 #include "igt_kms.h"
32 #include "igt_edid.h"
33 
34 static const unsigned char edid_header[] = {
35 	0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00
36 };
37 
38 /**
39  * Sanity check the header of the base EDID block.
40  */
edid_header_is_valid(const unsigned char * raw_edid)41 static bool edid_header_is_valid(const unsigned char *raw_edid)
42 {
43 	size_t i;
44 
45 	for (i = 0; i < sizeof(edid_header); i++)
46 		if (raw_edid[i] != edid_header[i])
47 			return false;
48 
49 	return true;
50 }
51 
52 /**
53  * Sanity check the checksum of the EDID block.
54  */
edid_block_checksum(const unsigned char * raw_edid)55 static bool edid_block_checksum(const unsigned char *raw_edid)
56 {
57 	size_t i;
58 	unsigned char csum = 0;
59 
60 	for (i = 0; i < EDID_BLOCK_SIZE; i++) {
61 		csum += raw_edid[i];
62 	}
63 
64 	return csum == 0;
65 }
66 
67 typedef const struct edid *(*get_edid_func)(void);
68 
69 igt_simple_main
70 {
71 	const struct {
72 		const char *desc;
73 		get_edid_func f;
74 		size_t exts;
75 	} funcs[] = {
76 		{ "base", igt_kms_get_base_edid, 0 },
77 		{ "alt", igt_kms_get_alt_edid, 0 },
78 		{ "hdmi_audio", igt_kms_get_hdmi_audio_edid, 1 },
79 		{ "4k", igt_kms_get_4k_edid, 1 },
80 		{ "3d", igt_kms_get_3d_edid, 1 },
81 		{0},
82 	}, *f;
83 	const struct edid *edid;
84 	const uint8_t *raw_edid, *raw_block;
85 	size_t i;
86 
87 	for (f = funcs; f->f; f++) {
88 		edid = f->f();
89 		raw_edid = (uint8_t *) edid;
90 
91 		igt_assert_f(edid_header_is_valid(raw_edid),
92 			     "invalid header on %s EDID", f->desc);
93 		/* check base edid block */
94 		igt_assert_f(edid_block_checksum(raw_edid),
95 			     "checksum failed on %s EDID", f->desc);
96 		/* check extension blocks, if any */
97 		igt_assert_f(raw_edid[126] == f->exts,
98 			     "unexpected number of extensions on %s EDID",
99 			     f->desc);
100 		for (i = 0; i < f->exts; i++) {
101 			raw_block = raw_edid + (i + 1) * EDID_BLOCK_SIZE;
102 			igt_assert_f(edid_block_checksum(raw_block),
103 				     "CEA block checksum failed on %s EDID",
104 				     f->desc);
105 		}
106 	}
107 }
108