1 /*
2  * Copyright (C) 2013-2019 Red Hat
3  * Copyright (c) 2018 DisplayLink (UK) Ltd.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation; either version 2 of the
8  * License, or (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful, but
11  * WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
18  * 02111-1307, USA.
19  */
20 
21 #include "config.h"
22 
23 #include "backends/native/meta-kms-utils.h"
24 
25 #include <drm_fourcc.h>
26 #include <glib.h>
27 
28 /* added in libdrm 2.4.95 */
29 #ifndef DRM_FORMAT_INVALID
30 #define DRM_FORMAT_INVALID 0
31 #endif
32 
33 float
meta_calculate_drm_mode_refresh_rate(const drmModeModeInfo * drm_mode)34 meta_calculate_drm_mode_refresh_rate (const drmModeModeInfo *drm_mode)
35 {
36   double numerator;
37   double denominator;
38 
39   if (drm_mode->htotal <= 0 || drm_mode->vtotal <= 0)
40     return 0.0;
41 
42   numerator = drm_mode->clock * 1000.0;
43   denominator = (double) drm_mode->vtotal * drm_mode->htotal;
44   if (drm_mode->vscan > 1)
45     denominator *= drm_mode->vscan;
46 
47   return numerator / denominator;
48 }
49 
50 int64_t
meta_calculate_drm_mode_vblank_duration_us(const drmModeModeInfo * drm_mode)51 meta_calculate_drm_mode_vblank_duration_us (const drmModeModeInfo *drm_mode)
52 {
53   int64_t value;
54 
55   if (drm_mode->htotal <= 0 || drm_mode->vtotal <= 0)
56     return 0;
57 
58   /* Convert to int64_t early. */
59   value = drm_mode->vtotal - drm_mode->vdisplay;
60   value *= drm_mode->htotal;
61 
62   if (drm_mode->flags & DRM_MODE_FLAG_DBLSCAN)
63     value *= 2;
64 
65   /* Round the duration up as it is used for buffer swap deadline computation. */
66   value = (value * 1000 + drm_mode->clock - 1) / drm_mode->clock;
67 
68   return value;
69 }
70 
71 /**
72  * meta_drm_format_to_string:
73  * @tmp: temporary buffer
74  * @drm_format: DRM fourcc pixel format
75  *
76  * Returns a pointer to a string naming the given pixel format,
77  * usually a pointer to the temporary buffer but not always.
78  * Invalid formats may return nonsense names.
79  *
80  * When calling this, allocate one MetaDrmFormatBuf on the stack to
81  * be used as the temporary buffer.
82  */
83 const char *
meta_drm_format_to_string(MetaDrmFormatBuf * tmp,uint32_t drm_format)84 meta_drm_format_to_string (MetaDrmFormatBuf *tmp,
85                            uint32_t          drm_format)
86 {
87   int i;
88 
89   if (drm_format == DRM_FORMAT_INVALID)
90     return "INVALID";
91 
92   G_STATIC_ASSERT (sizeof (tmp->s) == 5);
93   for (i = 0; i < 4; i++)
94     {
95       char c = (drm_format >> (i * 8)) & 0xff;
96       tmp->s[i] = g_ascii_isgraph (c) ? c : '.';
97     }
98 
99   tmp->s[i] = 0;
100 
101   return tmp->s;
102 }
103 
104