SecBSD/xenocara
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

sync code with last improvements from OpenBSD

Browse source
This commit is contained in:
purplerain 2023-08-28 05:57:34 +00:00
commit 88965415ff
Signed by: purplerain
GPG key ID: F42C07F07E2E35B7
26235 changed files with 29195616 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

21
lib/libdrm/mk/man/Makefile Normal file
View file

@ -0,0 +1,21 @@
MDOCS= drmAvailable 3 drmHandleEvent 3 drmModeGetResources 3 \
drm 7 drm-kms 7 drm-memory 7
beforeinstall:
.for n s in ${MDOCS}
${INSTALL} ${INSTALL_COPY} -o ${MANOWN} -g ${MANGRP} -m ${MANMODE} \
${.CURDIR}/${n}.${s} ${DESTDIR}${MANDIR}${s}
.endfor
# maintainer target, not used duing build or install
mdoc:
.for n s in ${MDOCS}
rst2man ${DRM_SRC}/man/${n}.${s}.rst> ${.CURDIR}/${n}.${s}
.endfor
obj: _xenocara_obj
.include <bsd.prog.mk>
.include <bsd.xorg.mk>
.PHONY: mdoc

240
lib/libdrm/mk/man/drm-kms.7 Normal file
View file

@ -0,0 +1,240 @@
.\" Man page generated from reStructuredText.
.
.
.nr rst2man-indent-level 0
.
.de1 rstReportMargin
\\$1 \\n[an-margin]
level \\n[rst2man-indent-level]
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
-
\\n[rst2man-indent0]
\\n[rst2man-indent1]
\\n[rst2man-indent2]
..
.de1 INDENT
.\" .rstReportMargin pre:
. RS \\$1
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
. nr rst2man-indent-level +1
.\" .rstReportMargin post:
..
.de UNINDENT
. RE
.\" indent \\n[an-margin]
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
.nr rst2man-indent-level -1
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
..
.TH "DRM-KMS" 7 "September 2012" "" "Direct Rendering Manager"
.SH NAME
drm-kms \- Kernel Mode-Setting
.SH SYNOPSIS
.sp
\fB#include <xf86drm.h>\fP
.sp
\fB#include <xf86drmMode.h>\fP
.SH DESCRIPTION
.sp
Each DRM device provides access to manage which monitors and displays are
currently used and what frames to be displayed. This task is called \fIKernel
Mode\-Setting\fP (KMS). Historically, this was done in user\-space and called
\fIUser\-space Mode\-Setting\fP (UMS). Almost all open\-source drivers now provide the
KMS kernel API to do this in the kernel, however, many non\-open\-source binary
drivers from different vendors still do not support this. You can use
\fBdrmModeSettingSupported\fP(3) to check whether your driver supports this. To
understand how KMS works, we need to introduce 5 objects: \fICRTCs\fP, \fIPlanes\fP,
\fIEncoders\fP, \fIConnectors\fP and \fIFramebuffers\fP\&.
.INDENT 0.0
.TP
.B CRTCs
A \fICRTC\fP short for \fICRT Controller\fP is an abstraction representing a part of
the chip that contains a pointer to a scanout buffer. Therefore, the number
of CRTCs available determines how many independent scanout buffers can be
active at any given time. The CRTC structure contains several fields to
support this: a pointer to some video memory (abstracted as a frame\-buffer
object), a list of driven connectors, a display mode and an (x, y) offset
into the video memory to support panning or configurations where one piece
of video memory spans multiple CRTCs. A CRTC is the central point where
configuration of displays happens. You select which objects to use, which
modes and which parameters and then configure each CRTC via
\fBdrmModeCrtcSet\fP(3) to drive the display devices.
.TP
.B Planes
A \fIplane\fP respresents an image source that can be blended with or overlayed
on top of a CRTC during the scanout process. Planes are associated with a
frame\-buffer to crop a portion of the image memory (source) and optionally
scale it to a destination size. The result is then blended with or overlayed
on top of a CRTC. Planes are not provided by all hardware and the number of
available planes is limited. If planes are not available or if not enough
planes are available, the user should fall back to normal software blending
(via GPU or CPU).
.TP
.B Encoders
An \fIencoder\fP takes pixel data from a CRTC and converts it to a format
suitable for any attached connectors. On some devices, it may be possible to
have a CRTC send data to more than one encoder. In that case, both encoders
would receive data from the same scanout buffer, resulting in a \fIcloned\fP
display configuration across the connectors attached to each encoder.
.TP
.B Connectors
A \fIconnector\fP is the final destination of pixel\-data on a device, and
usually connects directly to an external display device like a monitor or
laptop panel. A connector can only be attached to one encoder at a time. The
connector is also the structure where information about the attached display
is kept, so it contains fields for display data, \fIEDID\fP data, \fIDPMS\fP and
\fIconnection status\fP, and information about modes supported on the attached
displays.
.TP
.B Framebuffers
\fIFramebuffers\fP are abstract memory objects that provide a source of pixel
data to scanout to a CRTC. Applications explicitly request the creation of
framebuffers and can control their behavior. Framebuffers rely on the
underneath memory manager for low\-level memory operations. When creating a
framebuffer, applications pass a memory handle through the API which is used
as backing storage. The framebuffer itself is only an abstract object with
no data. It just refers to memory buffers that must be created with the
\fBdrm\-memory\fP(7) API.
.UNINDENT
.SS Mode\-Setting
.sp
Before mode\-setting can be performed, an application needs to call
\fBdrmSetMaster\fP(3) to become \fIDRM\-Master\fP\&. It then has exclusive access to
the KMS API. A call to \fBdrmModeGetResources\fP(3) returns a list of \fICRTCs\fP,
\fIConnectors\fP, \fIEncoders\fP and \fIPlanes\fP\&.
.sp
Normal procedure now includes: First, you select which connectors you want to
use. Users are mostly interested in which monitor or display\-panel is active so
you need to make sure to arrange them in the correct logical order and select
the correct ones to use. For each connector, you need to find a CRTC to drive
this connector. If you want to clone output to two or more connectors, you may
use a single CRTC for all cloned connectors (if the hardware supports this). To
find a suitable CRTC, you need to iterate over the list of encoders that are
available for each connector. Each encoder contains a list of CRTCs that it can
work with and you simply select one of these CRTCs. If you later program the
CRTC to control a connector, it automatically selects the best encoder.
However, this procedure is needed so your CRTC has at least one working encoder
for the selected connector. See the \fIExamples\fP section below for more
information.
.sp
All valid modes for a connector can be retrieved with a call to
\fBdrmModeGetConnector\fP(3) You need to select the mode you want to use and save it.
The first mode in the list is the default mode with the highest resolution
possible and often a suitable choice.
.sp
After you have a working connector+CRTC+mode combination, you need to create a
framebuffer that is used for scanout. Memory buffer allocation is
driver\-dependent and described in \fBdrm\-memory\fP(7). You need to create a
buffer big enough for your selected mode. Now you can create a framebuffer
object that uses your memory\-buffer as scanout buffer. You can do this with
\fBdrmModeAddFB\fP(3) and \fBdrmModeAddFB2\fP(3).
.sp
As a last step, you want to program your CRTC to drive your selected connector.
You can do this with a call to \fBdrmModeSetCrtc\fP(3).
.SS Page\-Flipping
.sp
A call to \fBdrmModeSetCrtc\fP(3) is executed immediately and forces the CRTC
to use the new scanout buffer. If you want smooth\-transitions without tearing,
you probably use double\-buffering. You need to create one framebuffer object
for each buffer you use. You can then call \fBdrmModeSetCrtc\fP(3) on the next
buffer to flip. If you want to synchronize your flips with \fIvertical\-blanks\fP,
you can use \fBdrmModePageFlip\fP(3) which schedules your page\-flip for the
next \fIvblank\fP\&.
.SS Planes
.sp
Planes are controlled independently from CRTCs. That is, a call to
\fBdrmModeSetCrtc\fP(3) does not affect planes. Instead, you need to call
\fBdrmModeSetPlane\fP(3) to configure a plane. This requires the plane ID, a
CRTC, a framebuffer and offsets into the plane\-framebuffer and the
CRTC\-framebuffer. The CRTC then blends the content from the plane over the CRTC
framebuffer buffer during scanout. As this does not involve any
software\-blending, it is way faster than traditional blending. However, plane
resources are limited. See \fBdrmModeGetPlaneResources\fP(3) for more
information.
.SS Cursors
.sp
Similar to planes, many hardware also supports cursors. A cursor is a very
small buffer with an image that is blended over the CRTC framebuffer. You can
set a different cursor for each CRTC with \fBdrmModeSetCursor\fP(3) and move it
on the screen with \fBdrmModeMoveCursor\fP(3). This allows to move the cursor
on the screen without rerendering. If no hardware cursors are supported, you
need to rerender for each frame the cursor is moved.
.SH EXAMPLES
.sp
Some examples of how basic mode\-setting can be done. See the man\-page of each
DRM function for more information.
.SS CRTC/Encoder Selection
.sp
If you retrieved all display configuration information via
\fBdrmModeGetResources\fP(3) as \fBdrmModeRes *res\fP, selected a connector from
the list in \fBres\->connectors\fP and retrieved the connector\-information as
\fBdrmModeConnector *conn\fP via \fBdrmModeGetConnector\fP(3) then this example
shows, how you can find a suitable CRTC id to drive this connector. This
function takes a file\-descriptor to the DRM device (see \fBdrmOpen\fP(3)) as
\fBfd\fP, a pointer to the retrieved resources as \fBres\fP and a pointer to the
selected connector as \fBconn\fP\&. It returns an integer smaller than 0 on
failure, otherwise, a valid CRTC id is returned.
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
static int modeset_find_crtc(int fd, drmModeRes *res, drmModeConnector *conn)
{
drmModeEncoder *enc;
unsigned int i, j;
/* iterate all encoders of this connector */
for (i = 0; i < conn\->count_encoders; ++i) {
enc = drmModeGetEncoder(fd, conn\->encoders[i]);
if (!enc) {
/* cannot retrieve encoder, ignoring... */
continue;
}
/* iterate all global CRTCs */
for (j = 0; j < res\->count_crtcs; ++j) {
/* check whether this CRTC works with the encoder */
if (!(enc\->possible_crtcs & (1 << j)))
continue;
/* Here you need to check that no other connector
* currently uses the CRTC with id \(dqcrtc\(dq. If you intend
* to drive one connector only, then you can skip this
* step. Otherwise, simply scan your list of configured
* connectors and CRTCs whether this CRTC is already
* used. If it is, then simply continue the search here. */
if (res\->crtcs[j] \(dqis unused\(dq) {
drmModeFreeEncoder(enc);
return res\->crtcs[j];
}
}
drmModeFreeEncoder(enc);
}
/* cannot find a suitable CRTC */
return \-ENOENT;
}
.ft P
.fi
.UNINDENT
.UNINDENT
.SH REPORTING BUGS
.sp
Bugs in this manual should be reported to
\fI\%https://gitlab.freedesktop.org/mesa/drm/\-/issues\fP
.SH SEE ALSO
.sp
\fBdrm\fP(7), \fBdrm\-memory\fP(7), \fBdrmModeGetResources\fP(3),
\fBdrmModeGetConnector\fP(3), \fBdrmModeGetEncoder\fP(3),
\fBdrmModeGetCrtc\fP(3), \fBdrmModeSetCrtc\fP(3), \fBdrmModeGetFB\fP(3),
\fBdrmModeAddFB\fP(3), \fBdrmModeAddFB2\fP(3), \fBdrmModeRmFB\fP(3),
\fBdrmModePageFlip\fP(3), \fBdrmModeGetPlaneResources\fP(3),
\fBdrmModeGetPlane\fP(3), \fBdrmModeSetPlane\fP(3), \fBdrmModeSetCursor\fP(3),
\fBdrmModeMoveCursor\fP(3), \fBdrmSetMaster\fP(3), \fBdrmAvailable\fP(3),
\fBdrmCheckModesettingSupported\fP(3), \fBdrmOpen\fP(3)
.\" Generated by docutils manpage writer.
.

354
lib/libdrm/mk/man/drm-memory.7 Normal file
View file

@ -0,0 +1,354 @@
.\" Man page generated from reStructuredText.
.
.
.nr rst2man-indent-level 0
.
.de1 rstReportMargin
\\$1 \\n[an-margin]
level \\n[rst2man-indent-level]
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
-
\\n[rst2man-indent0]
\\n[rst2man-indent1]
\\n[rst2man-indent2]
..
.de1 INDENT
.\" .rstReportMargin pre:
. RS \\$1
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
. nr rst2man-indent-level +1
.\" .rstReportMargin post:
..
.de UNINDENT
. RE
.\" indent \\n[an-margin]
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
.nr rst2man-indent-level -1
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
..
.TH "DRM-MEMORY" 7 "September 2012" "" "Direct Rendering Manager"
.SH NAME
drm-memory \- DRM Memory Management
.SH SYNOPSIS
.sp
\fB#include <xf86drm.h>\fP
.SH DESCRIPTION
.sp
Many modern high\-end GPUs come with their own memory managers. They even
include several different caches that need to be synchronized during access.
Textures, framebuffers, command buffers and more need to be stored in memory
that can be accessed quickly by the GPU. Therefore, memory management on GPUs
is highly driver\- and hardware\-dependent.
.sp
However, there are several frameworks in the kernel that are used by more than
one driver. These can be used for trivial mode\-setting without requiring
driver\-dependent code. But for hardware\-accelerated rendering you need to read
the manual pages for the driver you want to work with.
.SS Dumb\-Buffers
.sp
Almost all in\-kernel DRM hardware drivers support an API called \fIDumb\-Buffers\fP\&.
This API allows to create buffers of arbitrary size that can be used for
scanout. These buffers can be memory mapped via \fBmmap\fP(2) so you can render
into them on the CPU. However, GPU access to these buffers is often not
possible. Therefore, they are fine for simple tasks but not suitable for
complex compositions and renderings.
.sp
The \fBDRM_IOCTL_MODE_CREATE_DUMB\fP ioctl can be used to create a dumb buffer.
The kernel will return a 32\-bit handle that can be used to manage the buffer
with the DRM API. You can create framebuffers with \fBdrmModeAddFB\fP(3) and
use it for mode\-setting and scanout. To access the buffer, you first need to
retrieve the offset of the buffer. The \fBDRM_IOCTL_MODE_MAP_DUMB\fP ioctl
requests the DRM subsystem to prepare the buffer for memory\-mapping and returns
a fake\-offset that can be used with \fBmmap\fP(2).
.sp
The \fBDRM_IOCTL_MODE_CREATE_DUMB\fP ioctl takes as argument a structure of type
\fBstruct drm_mode_create_dumb\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
struct drm_mode_create_dumb {
__u32 height;
__u32 width;
__u32 bpp;
__u32 flags;
__u32 handle;
__u32 pitch;
__u64 size;
};
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
The fields \fIheight\fP, \fIwidth\fP, \fIbpp\fP and \fIflags\fP have to be provided by the
caller. The other fields are filled by the kernel with the return values.
\fIheight\fP and \fIwidth\fP are the dimensions of the rectangular buffer that is
created. \fIbpp\fP is the number of bits\-per\-pixel and must be a multiple of 8. You
most commonly want to pass 32 here. The flags field is currently unused and
must be zeroed. Different flags to modify the behavior may be added in the
future. After calling the ioctl, the handle, pitch and size fields are filled
by the kernel. \fIhandle\fP is a 32\-bit gem handle that identifies the buffer. This
is used by several other calls that take a gem\-handle or memory\-buffer as
argument. The \fIpitch\fP field is the pitch (or stride) of the new buffer. Most
drivers use 32\-bit or 64\-bit aligned stride\-values. The size field contains the
absolute size in bytes of the buffer. This can normally also be computed with
\fB(height * pitch + width) * bpp / 4\fP\&.
.sp
To prepare the buffer for \fBmmap\fP(2) you need to use the
\fBDRM_IOCTL_MODE_MAP_DUMB\fP ioctl. It takes as argument a structure of type
\fBstruct drm_mode_map_dumb\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
struct drm_mode_map_dumb {
__u32 handle;
__u32 pad;
__u64 offset;
};
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
You need to put the gem\-handle that was previously retrieved via
\fBDRM_IOCTL_MODE_CREATE_DUMB\fP into the \fIhandle\fP field. The \fIpad\fP field is
unused padding and must be zeroed. After completion, the \fIoffset\fP field will
contain an offset that can be used with \fBmmap\fP(2) on the DRM
file\-descriptor.
.sp
If you don\(aqt need your dumb\-buffer, anymore, you have to destroy it with
\fBDRM_IOCTL_MODE_DESTROY_DUMB\fP\&. If you close the DRM file\-descriptor, all open
dumb\-buffers are automatically destroyed. This ioctl takes as argument a
structure of type \fBstruct drm_mode_destroy_dumb\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
struct drm_mode_destroy_dumb {
__u32 handle;
};
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
You only need to put your handle into the \fIhandle\fP field. After this call, the
handle is invalid and may be reused for new buffers by the dumb\-API.
.SS TTM
.sp
\fITTM\fP stands for \fITranslation Table Manager\fP and is a generic memory\-manager
provided by the kernel. It does not provide a common user\-space API so you need
to look at each driver interface if you want to use it. See for instance the
radeon man pages for more information on memory\-management with radeon and TTM.
.SS GEM
.sp
\fIGEM\fP stands for \fIGraphics Execution Manager\fP and is a generic DRM
memory\-management framework in the kernel, that is used by many different
drivers. GEM is designed to manage graphics memory, control access to the
graphics device execution context and handle essentially NUMA environment
unique to modern graphics hardware. GEM allows multiple applications to share
graphics device resources without the need to constantly reload the entire
graphics card. Data may be shared between multiple applications with gem
ensuring that the correct memory synchronization occurs.
.sp
GEM provides simple mechanisms to manage graphics data and control execution
flow within the linux DRM subsystem. However, GEM is not a complete framework
that is fully driver independent. Instead, if provides many functions that are
shared between many drivers, but each driver has to implement most of
memory\-management with driver\-dependent ioctls. This manpage tries to describe
the semantics (and if it applies, the syntax) that is shared between all
drivers that use GEM.
.sp
All GEM APIs are defined as \fBioctl\fP(2) on the DRM file descriptor. An
application must be authorized via \fBdrmAuthMagic\fP(3) to the current
DRM\-Master to access the GEM subsystem. A driver that does not support GEM will
return \fBENODEV\fP for all these ioctls. Invalid object handles return
\fBEINVAL\fP and invalid object names return \fBENOENT\fP\&.
.sp
Gem provides explicit memory management primitives. System pages are allocated
when the object is created, either as the fundamental storage for hardware
where system memory is used by the graphics processor directly, or as backing
store for graphics\-processor resident memory.
.sp
Objects are referenced from user\-space using handles. These are, for all
intents and purposes, equivalent to file descriptors but avoid the overhead.
Newer kernel drivers also support the \fBdrm\-prime\fP (7) infrastructure which
can return real file\-descriptor for GEM\-handles using the linux DMA\-BUF API.
Objects may be published with a name so that other applications and processes
can access them. The name remains valid as long as the object exists.
GEM\-objects are reference counted in the kernel. The object is only destroyed
when all handles from user\-space were closed.
.sp
GEM\-buffers cannot be created with a generic API. Each driver provides its own
API to create GEM\-buffers. See for example \fBDRM_I915_GEM_CREATE\fP,
\fBDRM_NOUVEAU_GEM_NEW\fP or \fBDRM_RADEON_GEM_CREATE\fP\&. Each of these ioctls
returns a GEM\-handle that can be passed to different generic ioctls. The
\fIlibgbm\fP library from the \fImesa3D\fP distribution tries to provide a
driver\-independent API to create GBM buffers and retrieve a GBM\-handle to them.
It allows to create buffers for different use\-cases including scanout,
rendering, cursors and CPU\-access. See the libgbm library for more information
or look at the driver\-dependent man\-pages (for example \fBdrm\-intel\fP(7) or
\fBdrm\-radeon\fP(7)).
.sp
GEM\-buffers can be closed with \fBdrmCloseBufferHandle\fP(3). It takes as
argument the GEM\-handle to be closed. After this call the GEM handle cannot be
used by this process anymore and may be reused for new GEM objects by the GEM
API.
.sp
If you want to share GEM\-objects between different processes, you can create a
name for them and pass this name to other processes which can then open this
GEM\-object. Names are currently 32\-bit integer IDs and have no special
protection. That is, if you put a name on your GEM\-object, every other client
that has access to the DRM device and is authenticated via
\fBdrmAuthMagic\fP(3) to the current DRM\-Master, can \fIguess\fP the name and open
or access the GEM\-object. If you want more fine\-grained access control, you can
use the new \fBdrm\-prime\fP(7) API to retrieve file\-descriptors for
GEM\-handles. To create a name for a GEM\-handle, you use the
\fBDRM_IOCTL_GEM_FLINK\fP ioctl. It takes as argument a structure of type
\fBstruct drm_gem_flink\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
struct drm_gem_flink {
__u32 handle;
__u32 name;
};
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
You have to put your handle into the \fIhandle\fP field. After completion, the
kernel has put the new unique name into the name field. You can now pass
this name to other processes which can then import the name with the
\fBDRM_IOCTL_GEM_OPEN\fP ioctl. It takes as argument a structure of type
\fBstruct drm_gem_open\fP:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
struct drm_gem_open {
__u32 name;
__u32 handle;
__u32 size;
};
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
You have to fill in the \fIname\fP field with the name of the GEM\-object that you
want to open. The kernel will fill in the \fIhandle\fP and \fIsize\fP fields with the
new handle and size of the GEM\-object. You can now access the GEM\-object via
the handle as if you created it with the GEM API.
.sp
Besides generic buffer management, the GEM API does not provide any generic
access. Each driver implements its own functionality on top of this API. This
includes execution\-buffers, GTT management, context creation, CPU access, GPU
I/O and more. The next higher\-level API is \fIOpenGL\fP\&. So if you want to use more
GPU features, you should use the \fImesa3D\fP library to create OpenGL contexts on
DRM devices. This does \fInot\fP require any windowing\-system like X11, but can
also be done on raw DRM devices. However, this is beyond the scope of this
man\-page. You may have a look at other mesa3D man pages, including libgbm and
libEGL. 2D software\-rendering (rendering with the CPU) can be achieved with the
dumb\-buffer\-API in a driver\-independent fashion, however, for
hardware\-accelerated 2D or 3D rendering you must use OpenGL. Any other API that
tries to abstract the driver\-internals to access GEM\-execution\-buffers and
other GPU internals, would simply reinvent OpenGL so it is not provided. But if
you need more detailed information for a specific driver, you may have a look
into the driver\-manpages, including \fBdrm\-intel\fP(7), \fBdrm\-radeon\fP(7) and
\fBdrm\-nouveau\fP(7). However, the \fBdrm\-prime\fP(7) infrastructure and the
generic GEM API as described here allow display\-managers to handle
graphics\-buffers and render\-clients without any deeper knowledge of the GPU
that is used. Moreover, it allows to move objects between GPUs and implement
complex display\-servers that don\(aqt do any rendering on their own. See its
man\-page for more information.
.SH EXAMPLES
.sp
This section includes examples for basic memory\-management tasks.
.SS Dumb\-Buffers
.sp
This examples shows how to create a dumb\-buffer via the generic DRM API.
This is driver\-independent (as long as the driver supports dumb\-buffers)
and provides memory\-mapped buffers that can be used for scanout. This
example creates a full\-HD 1920x1080 buffer with 32 bits\-per\-pixel and a
color\-depth of 24 bits. The buffer is then bound to a framebuffer which
can be used for scanout with the KMS API (see \fBdrm\-kms\fP(7)).
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
struct drm_mode_create_dumb creq;
struct drm_mode_destroy_dumb dreq;
struct drm_mode_map_dumb mreq;
uint32_t fb;
int ret;
void *map;
/* create dumb buffer */
memset(&creq, 0, sizeof(creq));
creq.width = 1920;
creq.height = 1080;
creq.bpp = 32;
ret = drmIoctl(fd, DRM_IOCTL_MODE_CREATE_DUMB, &creq);
if (ret < 0) {
/* buffer creation failed; see \(dqerrno\(dq for more error codes */
...
}
/* creq.pitch, creq.handle and creq.size are filled by this ioctl with
* the requested values and can be used now. */
/* create framebuffer object for the dumb\-buffer */
ret = drmModeAddFB(fd, 1920, 1080, 24, 32, creq.pitch, creq.handle, &fb);
if (ret) {
/* frame buffer creation failed; see \(dqerrno\(dq */
...
}
/* the framebuffer \(dqfb\(dq can now used for scanout with KMS */
/* prepare buffer for memory mapping */
memset(&mreq, 0, sizeof(mreq));
mreq.handle = creq.handle;
ret = drmIoctl(fd, DRM_IOCTL_MODE_MAP_DUMB, &mreq);
if (ret) {
/* DRM buffer preparation failed; see \(dqerrno\(dq */
...
}
/* mreq.offset now contains the new offset that can be used with mmap() */
/* perform actual memory mapping */
map = mmap(0, creq.size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, mreq.offset);
if (map == MAP_FAILED) {
/* memory\-mapping failed; see \(dqerrno\(dq */
...
}
/* clear the framebuffer to 0 */
memset(map, 0, creq.size);
.ft P
.fi
.UNINDENT
.UNINDENT
.SH REPORTING BUGS
.sp
Bugs in this manual should be reported to
\fI\%https://gitlab.freedesktop.org/mesa/drm/\-/issues\fP
.SH SEE ALSO
.sp
\fBdrm\fP(7), \fBdrm\-kms\fP(7), \fBdrm\-prime\fP(7), \fBdrmAvailable\fP(3),
\fBdrmOpen\fP(3), \fBdrm\-intel\fP(7), \fBdrm\-radeon\fP(7), \fBdrm\-nouveau\fP(7)
.\" Generated by docutils manpage writer.
.

100
lib/libdrm/mk/man/drm.7 Normal file
View file

@ -0,0 +1,100 @@
.\" Man page generated from reStructuredText.
.
.
.nr rst2man-indent-level 0
.
.de1 rstReportMargin
\\$1 \\n[an-margin]
level \\n[rst2man-indent-level]
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
-
\\n[rst2man-indent0]
\\n[rst2man-indent1]
\\n[rst2man-indent2]
..
.de1 INDENT
.\" .rstReportMargin pre:
. RS \\$1
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
. nr rst2man-indent-level +1
.\" .rstReportMargin post:
..
.de UNINDENT
. RE
.\" indent \\n[an-margin]
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
.nr rst2man-indent-level -1
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
..
.TH "DRM" 7 "September 2012" "" "Direct Rendering Manager"
.SH NAME
drm \- Direct Rendering Manager
.SH SYNOPSIS
.sp
\fB#include <xf86drm.h>\fP
.SH DESCRIPTION
.sp
The \fIDirect Rendering Manager\fP (DRM) is a framework to manage \fIGraphics
Processing Units\fP (GPUs). It is designed to support the needs of complex
graphics devices, usually containing programmable pipelines well suited
to 3D graphics acceleration. Furthermore, it is responsible for memory
management, interrupt handling and DMA to provide a uniform interface to
applications.
.sp
In earlier days, the kernel framework was solely used to provide raw
hardware access to privileged user\-space processes which implement all
the hardware abstraction layers. But more and more tasks were moved into
the kernel. All these interfaces are based on \fBioctl\fP(2) commands on
the DRM character device. The \fIlibdrm\fP library provides wrappers for these
system\-calls and many helpers to simplify the API.
.sp
When a GPU is detected, the DRM system loads a driver for the detected
hardware type. Each connected GPU is then presented to user\-space via a
character\-device that is usually available as \fB/dev/dri/card0\fP and can
be accessed with \fBopen\fP(2) and \fBclose\fP(2). However, it still
depends on the graphics driver which interfaces are available on these
devices. If an interface is not available, the syscalls will fail with
\fBEINVAL\fP\&.
.SS Authentication
.sp
All DRM devices provide authentication mechanisms. Only a DRM master is
allowed to perform mode\-setting or modify core state and only one user
can be DRM master at a time. See \fBdrmSetMaster\fP(3) for information
on how to become DRM master and what the limitations are. Other DRM users
can be authenticated to the DRM\-Master via \fBdrmAuthMagic\fP(3) so they
can perform buffer allocations and rendering.
.SS Mode\-Setting
.sp
Managing connected monitors and displays and changing the current modes
is called \fIMode\-Setting\fP\&. This is restricted to the current DRM master.
Historically, this was implemented in user\-space, but new DRM drivers
implement a kernel interface to perform mode\-setting called \fIKernel Mode
Setting\fP (KMS). If your hardware\-driver supports it, you can use the KMS
API provided by DRM. This includes allocating framebuffers, selecting
modes and managing CRTCs and encoders. See \fBdrm\-kms\fP(7) for more.
.SS Memory Management
.sp
The most sophisticated tasks for GPUs today is managing memory objects.
Textures, framebuffers, command\-buffers and all other kinds of commands
for the GPU have to be stored in memory. The DRM driver takes care of
managing all memory objects, flushing caches, synchronizing access and
providing CPU access to GPU memory. All memory management is hardware
driver dependent. However, two generic frameworks are available that are
used by most DRM drivers. These are the \fITranslation Table Manager\fP
(TTM) and the \fIGraphics Execution Manager\fP (GEM). They provide generic
APIs to create, destroy and access buffers from user\-space. However,
there are still many differences between the drivers so driver\-dependent
code is still needed. Many helpers are provided in \fIlibgbm\fP (Graphics
Buffer Manager) from the \fIMesa\fP project. For more information on DRM
memory management, see \fBdrm\-memory\fP(7).
.SH REPORTING BUGS
.sp
Bugs in this manual should be reported to
\fI\%https://gitlab.freedesktop.org/mesa/drm/\-/issues\fP\&.
.SH SEE ALSO
.sp
\fBdrm\-kms\fP(7), \fBdrm\-memory\fP(7), \fBdrmSetMaster\fP(3),
\fBdrmAuthMagic\fP(3), \fBdrmAvailable\fP(3), \fBdrmOpen\fP(3)
.\" Generated by docutils manpage writer.
.

54
lib/libdrm/mk/man/drmAvailable.3 Normal file
View file

@ -0,0 +1,54 @@
.\" Man page generated from reStructuredText.
.
.
.nr rst2man-indent-level 0
.
.de1 rstReportMargin
\\$1 \\n[an-margin]
level \\n[rst2man-indent-level]
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
-
\\n[rst2man-indent0]
\\n[rst2man-indent1]
\\n[rst2man-indent2]
..
.de1 INDENT
.\" .rstReportMargin pre:
. RS \\$1
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
. nr rst2man-indent-level +1
.\" .rstReportMargin post:
..
.de UNINDENT
. RE
.\" indent \\n[an-margin]
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
.nr rst2man-indent-level -1
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
..
.TH "DRMAVAILABLE" 3 "September 2012" "" "Direct Rendering Manager"
.SH NAME
drmAvailable \- determine whether a DRM kernel driver has been loaded
.SH SYNOPSIS
.sp
\fB#include <xf86drm.h>\fP
.sp
\fBint drmAvailable(void);\fP
.SH DESCRIPTION
.sp
\fBdrmAvailable\fP allows the caller to determine whether a kernel DRM
driver is loaded.
.SH RETURN VALUE
.sp
\fBdrmAvailable\fP returns 1 if a DRM driver is currently loaded.
Otherwise 0 is returned.
.SH REPORTING BUGS
.sp
Bugs in this function should be reported to
\fI\%https://gitlab.freedesktop.org/mesa/drm/\-/issues\fP
.SH SEE ALSO
.sp
\fBdrm\fP(7), \fBdrmOpen\fP(3)
.\" Generated by docutils manpage writer.
.

81
lib/libdrm/mk/man/drmHandleEvent.3 Normal file
View file

@ -0,0 +1,81 @@
.\" Man page generated from reStructuredText.
.
.
.nr rst2man-indent-level 0
.
.de1 rstReportMargin
\\$1 \\n[an-margin]
level \\n[rst2man-indent-level]
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
-
\\n[rst2man-indent0]
\\n[rst2man-indent1]
\\n[rst2man-indent2]
..
.de1 INDENT
.\" .rstReportMargin pre:
. RS \\$1
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
. nr rst2man-indent-level +1
.\" .rstReportMargin post:
..
.de UNINDENT
. RE
.\" indent \\n[an-margin]
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
.nr rst2man-indent-level -1
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
..
.TH "DRMHANDLEEVENT" 3 "September 2012" "" "Direct Rendering Manager"
.SH NAME
drmHandleEvent \- read and process pending DRM events
.SH SYNOPSIS
.sp
\fB#include <xf86drm.h>\fP
.sp
\fBint drmHandleEvent(int fd, drmEventContextPtr evctx);\fP
.SH DESCRIPTION
.sp
\fBdrmHandleEvent\fP processes outstanding DRM events on the DRM
file\-descriptor passed as \fBfd\fP\&. This function should be called after
the DRM file\-descriptor has polled readable; it will read the events and
use the passed\-in \fBevctx\fP structure to call function pointers with the
parameters noted below:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
typedef struct _drmEventContext {
int version;
void (*vblank_handler) (int fd,
unsigned int sequence,
unsigned int tv_sec,
unsigned int tv_usec,
void *user_data)
void (*page_flip_handler) (int fd,
unsigned int sequence,
unsigned int tv_sec,
unsigned int tv_usec,
void *user_data)
} drmEventContext, *drmEventContextPtr;
.ft P
.fi
.UNINDENT
.UNINDENT
.SH RETURN VALUE
.sp
\fBdrmHandleEvent\fP returns 0 on success, or if there is no data to
read from the file\-descriptor. Returns \-1 if the read on the
file\-descriptor fails or returns less than a full event record.
.SH REPORTING BUGS
.sp
Bugs in this function should be reported to
\fI\%https://gitlab.freedesktop.org/mesa/drm/\-/issues\fP
.SH SEE ALSO
.sp
\fBdrm\fP(7), \fBdrm\-kms\fP(7), \fBdrmModePageFlip\fP(3),
\fBdrmWaitVBlank\fP(3)
.\" Generated by docutils manpage writer.
.

111
lib/libdrm/mk/man/drmModeGetResources.3 Normal file
View file

@ -0,0 +1,111 @@
.\" Man page generated from reStructuredText.
.
.
.nr rst2man-indent-level 0
.
.de1 rstReportMargin
\\$1 \\n[an-margin]
level \\n[rst2man-indent-level]
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
-
\\n[rst2man-indent0]
\\n[rst2man-indent1]
\\n[rst2man-indent2]
..
.de1 INDENT
.\" .rstReportMargin pre:
. RS \\$1
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
. nr rst2man-indent-level +1
.\" .rstReportMargin post:
..
.de UNINDENT
. RE
.\" indent \\n[an-margin]
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
.nr rst2man-indent-level -1
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
..
.TH "DRMMODEGETRESOURCES" 3 "September 2012" "" "Direct Rendering Manager"
.SH NAME
drmModeGetResources \- retrieve current display configuration information
.SH SYNOPSIS
.sp
\fB#include <xf86drm.h>\fP
.sp
\fB#include <xf86drmMode.h>\fP
.sp
\fBdrmModeResPtr drmModeGetResources(int fd);\fP
.SH DESCRIPTION
.sp
\fBdrmModeGetResources\fP allocates, populates, and returns a drmModeRes
structure containing information about the current display
configuration. The structure contains the following fields:
.INDENT 0.0
.INDENT 3.5
.sp
.nf
.ft C
typedef struct _drmModeRes {
int count_fbs;
uint32_t *fbs;
int count_crtcs;
uint32_t *crtcs;
int count_connectors;
uint32_t *connectors;
int count_encoders;
uint32_t *encoders;
uint32_t min_width, max_width;
uint32_t min_height, max_height;
} drmModeRes, *drmModeResPtr;
.ft P
.fi
.UNINDENT
.UNINDENT
.sp
The \fIcount_fbs\fP and \fIfbs\fP fields indicate the number of currently allocated
framebuffer objects (i.e., objects that can be attached to a given CRTC
or sprite for display).
.sp
The \fIcount_crtcs\fP and \fIcrtcs\fP fields list the available CRTCs in the
configuration. A CRTC is simply an object that can scan out a
framebuffer to a display sink, and contains mode timing and relative
position information. CRTCs drive encoders, which are responsible for
converting the pixel stream into a specific display protocol (e.g., MIPI
or HDMI).
.sp
The \fIcount_connectors\fP and \fIconnectors\fP fields list the available physical
connectors on the system. Note that some of these may not be exposed
from the chassis (e.g., LVDS or eDP). Connectors are attached to
encoders and contain information about the attached display sink (e.g.,
width and height in mm, subpixel ordering, and various other
properties).
.sp
The \fIcount_encoders\fP and \fIencoders\fP fields list the available encoders on
the device. Each encoder may be associated with a CRTC, and may be used
to drive a particular encoder.
.sp
The \fImin_*\fP and \fImax_*\fP fields indicate the maximum size of a framebuffer
for this device (i.e., the scanout size limit).
.SH RETURN VALUE
.sp
\fBdrmModeGetResources\fP returns a drmModeRes structure pointer on
success, NULL on failure. The returned structure must be freed with
\fBdrmModeFreeResources\fP(3).
.SH REPORTING BUGS
.sp
Bugs in this function should be reported to
\fI\%https://gitlab.freedesktop.org/mesa/drm/\-/issues\fP
.SH SEE ALSO
.sp
\fBdrm\fP(7), \fBdrm\-kms\fP(7), \fBdrmModeGetFB\fP(3), \fBdrmModeAddFB\fP(3),
\fBdrmModeAddFB2\fP(3), \fBdrmModeRmFB\fP(3), \fBdrmModeDirtyFB\fP(3),
\fBdrmModeGetCrtc\fP(3), \fBdrmModeSetCrtc\fP (3), \fBdrmModeGetEncoder\fP (3),
\fBdrmModeGetConnector\fP(3)
.\" Generated by docutils manpage writer.
.