f82ff35e8e
This patch adds information about the new resolution-format that can be specified by a user in weston.ini to select a CEA mode. CEA defines timing of a video mode, which is considered as a standard for HDMI certification and compliance testing. It defines each and every parameter, of a video mode, like h/vactive,h/vfront h/vback etc., including aspect-ratio information. The drm layer, specifies the aspect-ratio information in user-mode flag bits 19-22. For the non-CEA modes a value of 0 is given in the aspect-ratio flag bits. Each CEA-mode is identified by a unique, Video Identification Code (VIC). For example, VIC=4 is 1280x720@60 aspect-ratio 16:9. This mode will be different than a non-CEA mode 1280x720@60 0:0. The new mode-format helps to differentiate between the CEA and non-CEA modes, by letting user specify aspect-ratio along with other paremeters: mode=widthxheight@rr ratio. This helps when certification testing is done, in tests like 7-27, the HDMI analyzer applies a particular CEA mode, and expects the applied mode to be with exactly same timings, including the aspect-ratio and VIC field. Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com> Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
200 lines
7.5 KiB
Groff
200 lines
7.5 KiB
Groff
.TH WESTON-DRM 7 "2012-11-27" "Weston __version__"
|
|
.SH NAME
|
|
weston-drm \- the DRM backend for Weston
|
|
.SH SYNOPSIS
|
|
.B weston-launch
|
|
.LP
|
|
.B weston --backend=drm-backend.so
|
|
.
|
|
.\" ***************************************************************
|
|
.SH DESCRIPTION
|
|
The DRM backend is the native Weston backend for systems that support
|
|
the Linux kernel DRM, kernel mode setting (KMS), and evdev input devices.
|
|
It is the recommended backend for desktop PCs, and aims to provide
|
|
the full Wayland experience with the "every frame is perfect" concept.
|
|
It also relies on the Mesa GBM interface.
|
|
|
|
With the DRM backend,
|
|
.B weston
|
|
runs without any underlying windowing system. The backend uses the
|
|
Linux KMS API to detect connected monitors. Monitor hot-plugging is
|
|
supported. Input devices are found automatically by
|
|
.BR udev (7).
|
|
Compositing happens mainly in GL\ ES\ 2, initialized through EGL. It
|
|
is also possible to take advantage of hardware cursors and overlays,
|
|
when they exist and are functional. Full-screen surfaces will be
|
|
scanned out directly without compositing, when possible.
|
|
Hardware accelerated clients are supported via EGL.
|
|
|
|
The backend chooses the DRM graphics device first based on seat id.
|
|
If seat identifiers are not set, it looks for the graphics device
|
|
that was used in boot. If that is not found, it finally chooses
|
|
the first DRM device returned by
|
|
.BR udev (7).
|
|
Combining multiple graphics devices are not supported yet.
|
|
|
|
The DRM backend relies on
|
|
.B weston-launch
|
|
for managing input device access and DRM master status, so that
|
|
.B weston
|
|
can be run without root privileges. On switching away from the
|
|
virtual terminal (VT) hosting Weston, all input devices are closed and
|
|
the DRM master capability is dropped, so that other servers,
|
|
including
|
|
.BR Xorg (1),
|
|
can run on other VTs. On switching back to Weston's VT, input devices
|
|
and DRM master are re-acquired through the parent process
|
|
.BR weston-launch .
|
|
.
|
|
.\" ***************************************************************
|
|
.SH CONFIGURATION
|
|
.
|
|
The DRM backend uses the following entries from
|
|
.BR weston.ini .
|
|
.SS Section output
|
|
.TP
|
|
\fBname\fR=\fIconnector\fR
|
|
The KMS connector name identifying the output, for instance
|
|
.IR LVDS1 .
|
|
.TP
|
|
\fBmode\fR=\fImode\fR
|
|
Specify the video mode for the output. The argument
|
|
.I mode
|
|
can be one of the words
|
|
.BR off " to turn the output off, "
|
|
.BR preferred " to use the monitor's preferred video mode, or "
|
|
.BR current " to use the current video mode and avoid a mode switch."
|
|
It can also be a resolution as:
|
|
.TP
|
|
\fBmode\fR=\fIwidth\fBx\fIheight\fR
|
|
.TP
|
|
\fBmode\fR=\fIwidth\fBx\fIheight\fB@\fIrefresh_rate\fR
|
|
Specify a mode with a given refresh-rate measured in Hz.
|
|
.TP
|
|
\fBmode\fR=\fIwidth\fBx\fIheight\fB@\fIrefresh_rate ratio\fR
|
|
Here \fIratio\fR is Picture Aspect-Ratio which can have values as 4:3, 16:9,
|
|
64:27, and 256:135. This resolution-format helps to select a CEA mode, if such a
|
|
video mode is present in the mode-list of the output.
|
|
|
|
CEA defines the timing of a video mode, which is considered as a standard for
|
|
HDMI spcification and compliance testing. It defines each and every parameter of
|
|
a video mode, like hactive, vactive, vfront, vback etc., including aspect-ratio
|
|
information. For CEA modes, the drm layer, stores this aspect-ratio information
|
|
in user-mode (drmModeModeInfo) flag bits 19-22. For the non-CEA modes a value of
|
|
0 is stored in the aspect-ratio flag bits.
|
|
|
|
Each CEA-mode is identified by a unique, Video Identification Code (VIC).
|
|
For example, VIC=4 is 1280x720@60 aspect-ratio 16:9. This mode will be
|
|
different than a non-CEA mode 1280x720@60 0:0. When the video mode
|
|
1280x720@60 0:0 is applied, since its timing doesnt exactly match with the CEA
|
|
information for VIC=4, it would be treated as a non-CEA mode. Also, while setting
|
|
the HDMI-AVI-Inforframe, VIC parameter will be given as '0'. If video mode
|
|
1280x720@60 16:9 is applied, its CEA timimgs matches with that of video mode with
|
|
VIC=4, so the VIC parameter in HDMI-AVI-Infoframe will be set to 4.
|
|
|
|
Many a times, an output may have both CEA and non-CEA modes, which are similar
|
|
in all resepct, differing only in the aspect-ratio. A user can select a CEA mode
|
|
by giving the aspect-ratio, along with the other arguments for the mode.
|
|
By omitting the aspect-ratio, user can specify the non-CEA modes.
|
|
This helps when certification testing is done, in tests like 7-27, the
|
|
HDMI-analyzer applies a particular CEA mode, and expects the applied mode to be
|
|
with exactly same timings, including the aspect-ratio and VIC field.
|
|
|
|
The resolution can also be a detailed mode line as below.
|
|
.TP
|
|
\fBmode\fR=\fIdotclock hdisp hsyncstart hsyncend htotal \
|
|
vdisp vsyncstart vsyncend vtotal hflag vflag\fR
|
|
Use the given detailed mode line as the video mode for this output.
|
|
The definition is the same as in
|
|
.BR xorg.conf "(5), and " cvt (1)
|
|
can generate detailed mode lines.
|
|
.TP
|
|
\fBtransform\fR=\fItransform\fR
|
|
Transform for the output, which can be rotated in 90-degree steps
|
|
and possibly flipped. Possible values are
|
|
.BR normal ", " 90 ", " 180 ", " 270 ", "
|
|
.BR flipped ", " flipped-90 ", " flipped-180 ", and " flipped-270 .
|
|
.TP
|
|
\fBpixman-shadow\fR=\fIboolean\fR
|
|
If using the Pixman-renderer, use shadow framebuffers. Defaults to
|
|
.BR true .
|
|
.TP
|
|
\fBsame-as\fR=\fIname\fR
|
|
Make this output (connector) a clone of another. The argument
|
|
.IR name " is the "
|
|
.BR name " value of another output section. The
|
|
referred to output section must exist. When this key is present in an
|
|
output section, all other keys have no effect on the configuration.
|
|
|
|
NOTE: cms-colord plugin does not work correctly with this option. The plugin
|
|
chooses an arbitrary monitor to load the color profile for, but the
|
|
profile is applied equally to all cloned monitors regardless of their
|
|
properties.
|
|
.TP
|
|
\fBforce-on\fR=\fItrue\fR
|
|
Force the output to be enabled even if the connector is disconnected.
|
|
Defaults to false. Note that
|
|
.BR mode=off " will override " force-on=true .
|
|
When a connector is disconnected, there is no EDID information to provide
|
|
a list of video modes. Therefore a forced output should also have a
|
|
detailed mode line specified.
|
|
.
|
|
.\" ***************************************************************
|
|
.SH OPTIONS
|
|
.
|
|
When the DRM backend is loaded,
|
|
.B weston
|
|
will understand the following additional command line options.
|
|
.TP
|
|
.B \-\-current\-mode
|
|
By default, use the current video mode of all outputs, instead of
|
|
switching to the monitor preferred mode.
|
|
.TP
|
|
\fB\-\-drm\-device\fR=\fIcardN\fR
|
|
Use the DRM device
|
|
.I cardN
|
|
instead of the default heuristics based on seat assignments and boot VGA
|
|
status. For example, use
|
|
.BR card0 .
|
|
.TP
|
|
\fB\-\-seat\fR=\fIseatid\fR
|
|
Use graphics and input devices designated for seat
|
|
.I seatid
|
|
instead of the seat defined in the environment variable
|
|
.BR XDG_SEAT ". If neither is specifed, seat0 will be assumed."
|
|
.TP
|
|
\fB\-\-tty\fR=\fIx\fR
|
|
Launch Weston on tty
|
|
.I x
|
|
instead of using the current tty.
|
|
.
|
|
.\" ***************************************************************
|
|
.SH ENVIRONMENT
|
|
.
|
|
.TP
|
|
.B WESTON_LIBINPUT_LOG_PRIORITY
|
|
The minimum libinput verbosity level to be printed to Weston's log.
|
|
Valid values are
|
|
.BR debug ", " info ", and " error ". Default is " info .
|
|
.TP
|
|
.B WESTON_TTY_FD
|
|
The file descriptor (integer) of the opened tty where
|
|
.B weston
|
|
will run. Set by
|
|
.BR weston-launch .
|
|
.TP
|
|
.B WESTON_LAUNCHER_SOCK
|
|
The file descriptor (integer) where
|
|
.B weston-launch
|
|
is listening. Automatically set by
|
|
.BR weston-launch .
|
|
.TP
|
|
.B XDG_SEAT
|
|
The seat Weston will start on, unless overridden on the command line.
|
|
.
|
|
.\" ***************************************************************
|
|
.SH "SEE ALSO"
|
|
.BR weston (1)
|
|
.\".BR weston-launch (1),
|
|
.\".BR weston.ini (5)
|