mutter/src/backends/native/meta-kms-utils.c
2021-07-13 08:09:42 +00:00

104 lines
2.7 KiB
C

/*
* Copyright (C) 2013-2019 Red Hat
* Copyright (c) 2018 DisplayLink (UK) Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*/
#include "config.h"
#include "backends/native/meta-kms-utils.h"
#include <drm_fourcc.h>
#include <glib.h>
/* added in libdrm 2.4.95 */
#ifndef DRM_FORMAT_INVALID
#define DRM_FORMAT_INVALID 0
#endif
float
meta_calculate_drm_mode_refresh_rate (const drmModeModeInfo *drm_mode)
{
double numerator;
double denominator;
if (drm_mode->htotal <= 0 || drm_mode->vtotal <= 0)
return 0.0;
numerator = drm_mode->clock * 1000.0;
denominator = (double) drm_mode->vtotal * drm_mode->htotal;
if (drm_mode->vscan > 1)
denominator *= drm_mode->vscan;
return numerator / denominator;
}
int64_t
meta_calculate_drm_mode_vblank_duration_us (const drmModeModeInfo *drm_mode)
{
int64_t value;
if (drm_mode->htotal <= 0 || drm_mode->vtotal <= 0)
return 0;
/* Convert to int64_t early. */
value = drm_mode->vtotal - drm_mode->vdisplay;
value *= drm_mode->htotal;
if (drm_mode->flags & DRM_MODE_FLAG_DBLSCAN)
value *= 2;
/* Round the duration up as it is used for buffer swap deadline computation. */
value = (value * 1000 + drm_mode->clock - 1) / drm_mode->clock;
return value;
}
/**
* meta_drm_format_to_string:
* @tmp: temporary buffer
* @drm_format: DRM fourcc pixel format
*
* Returns a pointer to a string naming the given pixel format,
* usually a pointer to the temporary buffer but not always.
* Invalid formats may return nonsense names.
*
* When calling this, allocate one MetaDrmFormatBuf on the stack to
* be used as the temporary buffer.
*/
const char *
meta_drm_format_to_string (MetaDrmFormatBuf *tmp,
uint32_t drm_format)
{
int i;
if (drm_format == DRM_FORMAT_INVALID)
return "INVALID";
G_STATIC_ASSERT (sizeof (tmp->s) == 5);
for (i = 0; i < 4; i++)
{
char c = (drm_format >> (i * 8)) & 0xff;
tmp->s[i] = g_ascii_isgraph (c) ? c : '.';
}
tmp->s[i] = 0;
return tmp->s;
}