提交 9253d059 编写于 作者: D Dave Airlie

Merge tag 'topic/drm-misc-2016-06-22-updated' of...

Merge tag 'topic/drm-misc-2016-06-22-updated' of git://anongit.freedesktop.org/drm-intel into drm-next

Again a pile of things all over
- Conversion to rst from docbook from Jani. Looks real pretty, and the
  source is now actually readable (compared to horrible, horrible docbook
  xml)! https://01.org/linuxgraphics/gfx-docs/drm/
- device register/unregister rework from Chris, with follow-up work from
  Benjamin. Allows more drivers to demidlayer load/unload and others to
  remove a bit of boilerplate.
- master/auth related cleanup, with docs
- some dma-buf polish, merged by Sumit
- small stuff all over (like build fixes from Arnd)

Group maintainership seems to slowly take off, with both Thierry and Sumit
pushing a few things. No hiccups thus far.

* tag 'topic/drm-misc-2016-06-22-updated' of git://anongit.freedesktop.org/drm-intel: (68 commits)
  drm/vc4: Remove unused connector
  drm/fb-helper: Reduce READ_ONCE(master) to lockless_dereference
  drm/sun4i: Remove open-coded drm_connector_register_all()
  drm/vc4: Remove open-coded drm_connector_register_all()
  drm/atmel-hlcdc: Remove redundant call to drm_connector_unregister_all()
  drm: document drm_auth.c
  drm: Clear up master tracking booleans
  drm: Extract drm_is_current_master
  drm: Refactor drop/set master code a bit
  drm: Lobotomize set_busid nonsense for !pci drivers
  drm: Nuke SET_UNIQUE ioctl
  drm: Don't call drm_dev_set_unique from platform drivers
  drm/vgem: Stop calling drm_drv_set_unique
  drm: Use dev->name as fallback for dev->unique
  drm: Clean up drm_crtc.h
  drm: Move master pointer from drm_minor to drm_device
  drm: sti: rework init sequence
  drm: sti: use late_register and early_unregister callbacks
  drm/amdkfd: Clean up inline handling
  drm: Add callbacks for late registering
  ...
......@@ -14,7 +14,7 @@ DOCBOOKS := z8530book.xml device-drivers.xml \
genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \
80211.xml debugobjects.xml sh.xml regulator.xml \
alsa-driver-api.xml writing-an-alsa-driver.xml \
tracepoint.xml gpu.xml media_api.xml w1.xml \
tracepoint.xml media_api.xml w1.xml \
writing_musb_glue_layer.xml crypto-API.xml iio.xml
include Documentation/DocBook/media/Makefile
......
此差异已折叠。
=============
DRM Internals
=============
This chapter documents DRM internals relevant to driver authors and
developers working to add support for the latest features to existing
drivers.
First, we go over some typical driver initialization requirements, like
setting up command buffers, creating an initial output configuration,
and initializing core services. Subsequent sections cover core internals
in more detail, providing implementation notes and examples.
The DRM layer provides several services to graphics drivers, many of
them driven by the application interfaces it provides through libdrm,
the library that wraps most of the DRM ioctls. These include vblank
event handling, memory management, output management, framebuffer
management, command submission & fencing, suspend/resume support, and
DMA services.
Driver Initialization
=====================
At the core of every DRM driver is a :c:type:`struct drm_driver
<drm_driver>` structure. Drivers typically statically initialize
a drm_driver structure, and then pass it to
:c:func:`drm_dev_alloc()` to allocate a device instance. After the
device instance is fully initialized it can be registered (which makes
it accessible from userspace) using :c:func:`drm_dev_register()`.
The :c:type:`struct drm_driver <drm_driver>` structure
contains static information that describes the driver and features it
supports, and pointers to methods that the DRM core will call to
implement the DRM API. We will first go through the :c:type:`struct
drm_driver <drm_driver>` static information fields, and will
then describe individual operations in details as they get used in later
sections.
Driver Information
------------------
Driver Features
~~~~~~~~~~~~~~~
Drivers inform the DRM core about their requirements and supported
features by setting appropriate flags in the driver_features field.
Since those flags influence the DRM core behaviour since registration
time, most of them must be set to registering the :c:type:`struct
drm_driver <drm_driver>` instance.
u32 driver_features;
DRIVER_USE_AGP
Driver uses AGP interface, the DRM core will manage AGP resources.
DRIVER_REQUIRE_AGP
Driver needs AGP interface to function. AGP initialization failure
will become a fatal error.
DRIVER_PCI_DMA
Driver is capable of PCI DMA, mapping of PCI DMA buffers to
userspace will be enabled. Deprecated.
DRIVER_SG
Driver can perform scatter/gather DMA, allocation and mapping of
scatter/gather buffers will be enabled. Deprecated.
DRIVER_HAVE_DMA
Driver supports DMA, the userspace DMA API will be supported.
Deprecated.
DRIVER_HAVE_IRQ; DRIVER_IRQ_SHARED
DRIVER_HAVE_IRQ indicates whether the driver has an IRQ handler
managed by the DRM Core. The core will support simple IRQ handler
installation when the flag is set. The installation process is
described in ?.
DRIVER_IRQ_SHARED indicates whether the device & handler support
shared IRQs (note that this is required of PCI drivers).
DRIVER_GEM
Driver use the GEM memory manager.
DRIVER_MODESET
Driver supports mode setting interfaces (KMS).
DRIVER_PRIME
Driver implements DRM PRIME buffer sharing.
DRIVER_RENDER
Driver supports dedicated render nodes.
DRIVER_ATOMIC
Driver supports atomic properties. In this case the driver must
implement appropriate obj->atomic_get_property() vfuncs for any
modeset objects with driver specific properties.
Major, Minor and Patchlevel
~~~~~~~~~~~~~~~~~~~~~~~~~~~
int major; int minor; int patchlevel;
The DRM core identifies driver versions by a major, minor and patch
level triplet. The information is printed to the kernel log at
initialization time and passed to userspace through the
DRM_IOCTL_VERSION ioctl.
The major and minor numbers are also used to verify the requested driver
API version passed to DRM_IOCTL_SET_VERSION. When the driver API
changes between minor versions, applications can call
DRM_IOCTL_SET_VERSION to select a specific version of the API. If the
requested major isn't equal to the driver major, or the requested minor
is larger than the driver minor, the DRM_IOCTL_SET_VERSION call will
return an error. Otherwise the driver's set_version() method will be
called with the requested version.
Name, Description and Date
~~~~~~~~~~~~~~~~~~~~~~~~~~
char \*name; char \*desc; char \*date;
The driver name is printed to the kernel log at initialization time,
used for IRQ registration and passed to userspace through
DRM_IOCTL_VERSION.
The driver description is a purely informative string passed to
userspace through the DRM_IOCTL_VERSION ioctl and otherwise unused by
the kernel.
The driver date, formatted as YYYYMMDD, is meant to identify the date of
the latest modification to the driver. However, as most drivers fail to
update it, its value is mostly useless. The DRM core prints it to the
kernel log at initialization time and passes it to userspace through the
DRM_IOCTL_VERSION ioctl.
Device Instance and Driver Handling
-----------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_drv.c
:doc: driver instance overview
.. kernel-doc:: drivers/gpu/drm/drm_drv.c
:export:
Driver Load
-----------
IRQ Registration
~~~~~~~~~~~~~~~~
The DRM core tries to facilitate IRQ handler registration and
unregistration by providing :c:func:`drm_irq_install()` and
:c:func:`drm_irq_uninstall()` functions. Those functions only
support a single interrupt per device, devices that use more than one
IRQs need to be handled manually.
Managed IRQ Registration
''''''''''''''''''''''''
:c:func:`drm_irq_install()` starts by calling the irq_preinstall
driver operation. The operation is optional and must make sure that the
interrupt will not get fired by clearing all pending interrupt flags or
disabling the interrupt.
The passed-in IRQ will then be requested by a call to
:c:func:`request_irq()`. If the DRIVER_IRQ_SHARED driver feature
flag is set, a shared (IRQF_SHARED) IRQ handler will be requested.
The IRQ handler function must be provided as the mandatory irq_handler
driver operation. It will get passed directly to
:c:func:`request_irq()` and thus has the same prototype as all IRQ
handlers. It will get called with a pointer to the DRM device as the
second argument.
Finally the function calls the optional irq_postinstall driver
operation. The operation usually enables interrupts (excluding the
vblank interrupt, which is enabled separately), but drivers may choose
to enable/disable interrupts at a different time.
:c:func:`drm_irq_uninstall()` is similarly used to uninstall an
IRQ handler. It starts by waking up all processes waiting on a vblank
interrupt to make sure they don't hang, and then calls the optional
irq_uninstall driver operation. The operation must disable all hardware
interrupts. Finally the function frees the IRQ by calling
:c:func:`free_irq()`.
Manual IRQ Registration
'''''''''''''''''''''''
Drivers that require multiple interrupt handlers can't use the managed
IRQ registration functions. In that case IRQs must be registered and
unregistered manually (usually with the :c:func:`request_irq()` and
:c:func:`free_irq()` functions, or their devm_\* equivalent).
When manually registering IRQs, drivers must not set the
DRIVER_HAVE_IRQ driver feature flag, and must not provide the
irq_handler driver operation. They must set the :c:type:`struct
drm_device <drm_device>` irq_enabled field to 1 upon
registration of the IRQs, and clear it to 0 after unregistering the
IRQs.
Memory Manager Initialization
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Every DRM driver requires a memory manager which must be initialized at
load time. DRM currently contains two memory managers, the Translation
Table Manager (TTM) and the Graphics Execution Manager (GEM). This
document describes the use of the GEM memory manager only. See ? for
details.
Miscellaneous Device Configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Another task that may be necessary for PCI devices during configuration
is mapping the video BIOS. On many devices, the VBIOS describes device
configuration, LCD panel timings (if any), and contains flags indicating
device state. Mapping the BIOS can be done using the pci_map_rom()
call, a convenience function that takes care of mapping the actual ROM,
whether it has been shadowed into memory (typically at address 0xc0000)
or exists on the PCI device in the ROM BAR. Note that after the ROM has
been mapped and any necessary information has been extracted, it should
be unmapped; on many devices, the ROM address decoder is shared with
other BARs, so leaving it mapped could cause undesired behaviour like
hangs or memory corruption.
Bus-specific Device Registration and PCI Support
------------------------------------------------
A number of functions are provided to help with device registration. The
functions deal with PCI and platform devices respectively and are only
provided for historical reasons. These are all deprecated and shouldn't
be used in new drivers. Besides that there's a few helpers for pci
drivers.
.. kernel-doc:: drivers/gpu/drm/drm_pci.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_platform.c
:export:
Open/Close, File Operations and IOCTLs
======================================
Open and Close
--------------
int (\*firstopen) (struct drm_device \*); void (\*lastclose) (struct
drm_device \*); int (\*open) (struct drm_device \*, struct drm_file
\*); void (\*preclose) (struct drm_device \*, struct drm_file \*);
void (\*postclose) (struct drm_device \*, struct drm_file \*);
Open and close handlers. None of those methods are mandatory.
The firstopen method is called by the DRM core for legacy UMS (User Mode
Setting) drivers only when an application opens a device that has no
other opened file handle. UMS drivers can implement it to acquire device
resources. KMS drivers can't use the method and must acquire resources
in the load method instead.
Similarly the lastclose method is called when the last application
holding a file handle opened on the device closes it, for both UMS and
KMS drivers. Additionally, the method is also called at module unload
time or, for hot-pluggable devices, when the device is unplugged. The
firstopen and lastclose calls can thus be unbalanced.
The open method is called every time the device is opened by an
application. Drivers can allocate per-file private data in this method
and store them in the struct :c:type:`struct drm_file
<drm_file>` driver_priv field. Note that the open method is
called before firstopen.
The close operation is split into preclose and postclose methods.
Drivers must stop and cleanup all per-file operations in the preclose
method. For instance pending vertical blanking and page flip events must
be cancelled. No per-file operation is allowed on the file handle after
returning from the preclose method.
Finally the postclose method is called as the last step of the close
operation, right before calling the lastclose method if no other open
file handle exists for the device. Drivers that have allocated per-file
private data in the open method should free it here.
The lastclose method should restore CRTC and plane properties to default
value, so that a subsequent open of the device will not inherit state
from the previous user. It can also be used to execute delayed power
switching state changes, e.g. in conjunction with the vga_switcheroo
infrastructure (see ?). Beyond that KMS drivers should not do any
further cleanup. Only legacy UMS drivers might need to clean up device
state so that the vga console or an independent fbdev driver could take
over.
File Operations
---------------
.. kernel-doc:: drivers/gpu/drm/drm_fops.c
:doc: file operations
.. kernel-doc:: drivers/gpu/drm/drm_fops.c
:export:
IOCTLs
------
struct drm_ioctl_desc \*ioctls; int num_ioctls;
Driver-specific ioctls descriptors table.
Driver-specific ioctls numbers start at DRM_COMMAND_BASE. The ioctls
descriptors table is indexed by the ioctl number offset from the base
value. Drivers can use the DRM_IOCTL_DEF_DRV() macro to initialize
the table entries.
::
DRM_IOCTL_DEF_DRV(ioctl, func, flags)
``ioctl`` is the ioctl name. Drivers must define the DRM_##ioctl and
DRM_IOCTL_##ioctl macros to the ioctl number offset from
DRM_COMMAND_BASE and the ioctl number respectively. The first macro is
private to the device while the second must be exposed to userspace in a
public header.
``func`` is a pointer to the ioctl handler function compatible with the
``drm_ioctl_t`` type.
::
typedef int drm_ioctl_t(struct drm_device *dev, void *data,
struct drm_file *file_priv);
``flags`` is a bitmask combination of the following values. It restricts
how the ioctl is allowed to be called.
- DRM_AUTH - Only authenticated callers allowed
- DRM_MASTER - The ioctl can only be called on the master file handle
- DRM_ROOT_ONLY - Only callers with the SYSADMIN capability allowed
- DRM_CONTROL_ALLOW - The ioctl can only be called on a control
device
- DRM_UNLOCKED - The ioctl handler will be called without locking the
DRM global mutex. This is the enforced default for kms drivers (i.e.
using the DRIVER_MODESET flag) and hence shouldn't be used any more
for new drivers.
.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c
:export:
Legacy Support Code
===================
The section very briefly covers some of the old legacy support code
which is only used by old DRM drivers which have done a so-called
shadow-attach to the underlying device instead of registering as a real
driver. This also includes some of the old generic buffer management and
command submission code. Do not use any of this in new and modern
drivers.
Legacy Suspend/Resume
---------------------
The DRM core provides some suspend/resume code, but drivers wanting full
suspend/resume support should provide save() and restore() functions.
These are called at suspend, hibernate, or resume time, and should
perform any state save or restore required by your device across suspend
or hibernate states.
int (\*suspend) (struct drm_device \*, pm_message_t state); int
(\*resume) (struct drm_device \*);
Those are legacy suspend and resume methods which *only* work with the
legacy shadow-attach driver registration functions. New driver should
use the power management interface provided by their bus type (usually
through the :c:type:`struct device_driver <device_driver>`
dev_pm_ops) and set these methods to NULL.
Legacy DMA Services
-------------------
This should cover how DMA mapping etc. is supported by the core. These
functions are deprecated and should not be used.
=============================
Mode Setting Helper Functions
=============================
The plane, CRTC, encoder and connector functions provided by the drivers
implement the DRM API. They're called by the DRM core and ioctl handlers
to handle device state changes and configuration request. As
implementing those functions often requires logic not specific to
drivers, mid-layer helper functions are available to avoid duplicating
boilerplate code.
The DRM core contains one mid-layer implementation. The mid-layer
provides implementations of several plane, CRTC, encoder and connector
functions (called from the top of the mid-layer) that pre-process
requests and call lower-level functions provided by the driver (at the
bottom of the mid-layer). For instance, the
:c:func:`drm_crtc_helper_set_config()` function can be used to
fill the :c:type:`struct drm_crtc_funcs <drm_crtc_funcs>`
set_config field. When called, it will split the set_config operation
in smaller, simpler operations and call the driver to handle them.
To use the mid-layer, drivers call
:c:func:`drm_crtc_helper_add()`,
:c:func:`drm_encoder_helper_add()` and
:c:func:`drm_connector_helper_add()` functions to install their
mid-layer bottom operations handlers, and fill the :c:type:`struct
drm_crtc_funcs <drm_crtc_funcs>`, :c:type:`struct
drm_encoder_funcs <drm_encoder_funcs>` and :c:type:`struct
drm_connector_funcs <drm_connector_funcs>` structures with
pointers to the mid-layer top API functions. Installing the mid-layer
bottom operation handlers is best done right after registering the
corresponding KMS object.
The mid-layer is not split between CRTC, encoder and connector
operations. To use it, a driver must provide bottom functions for all of
the three KMS entities.
Atomic Modeset Helper Functions Reference
=========================================
Overview
--------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:doc: overview
Implementing Asynchronous Atomic Commit
---------------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:doc: implementing nonblocking commit
Atomic State Reset and Initialization
-------------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:doc: atomic state reset and initialization
.. kernel-doc:: include/drm/drm_atomic_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:export:
Modeset Helper Reference for Common Vtables
===========================================
.. kernel-doc:: include/drm/drm_modeset_helper_vtables.h
:internal:
.. kernel-doc:: include/drm/drm_modeset_helper_vtables.h
:doc: overview
Legacy CRTC/Modeset Helper Functions Reference
==============================================
.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
:doc: overview
Output Probing Helper Functions Reference
=========================================
.. kernel-doc:: drivers/gpu/drm/drm_probe_helper.c
:doc: output probing helper overview
.. kernel-doc:: drivers/gpu/drm/drm_probe_helper.c
:export:
fbdev Helper Functions Reference
================================
.. kernel-doc:: drivers/gpu/drm/drm_fb_helper.c
:doc: fbdev helpers
.. kernel-doc:: drivers/gpu/drm/drm_fb_helper.c
:export:
.. kernel-doc:: include/drm/drm_fb_helper.h
:internal:
Framebuffer CMA Helper Functions Reference
==========================================
.. kernel-doc:: drivers/gpu/drm/drm_fb_cma_helper.c
:doc: framebuffer cma helper functions
.. kernel-doc:: drivers/gpu/drm/drm_fb_cma_helper.c
:export:
Display Port Helper Functions Reference
=======================================
.. kernel-doc:: drivers/gpu/drm/drm_dp_helper.c
:doc: dp helpers
.. kernel-doc:: include/drm/drm_dp_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_dp_helper.c
:export:
Display Port Dual Mode Adaptor Helper Functions Reference
=========================================================
.. kernel-doc:: drivers/gpu/drm/drm_dp_dual_mode_helper.c
:doc: dp dual mode helpers
.. kernel-doc:: include/drm/drm_dp_dual_mode_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_dp_dual_mode_helper.c
:export:
Display Port MST Helper Functions Reference
===========================================
.. kernel-doc:: drivers/gpu/drm/drm_dp_mst_topology.c
:doc: dp mst helper
.. kernel-doc:: include/drm/drm_dp_mst_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_dp_mst_topology.c
:export:
MIPI DSI Helper Functions Reference
===================================
.. kernel-doc:: drivers/gpu/drm/drm_mipi_dsi.c
:doc: dsi helpers
.. kernel-doc:: include/drm/drm_mipi_dsi.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_mipi_dsi.c
:export:
EDID Helper Functions Reference
===============================
.. kernel-doc:: drivers/gpu/drm/drm_edid.c
:export:
Rectangle Utilities Reference
=============================
.. kernel-doc:: include/drm/drm_rect.h
:doc: rect utils
.. kernel-doc:: include/drm/drm_rect.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_rect.c
:export:
Flip-work Helper Reference
==========================
.. kernel-doc:: include/drm/drm_flip_work.h
:doc: flip utils
.. kernel-doc:: include/drm/drm_flip_work.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_flip_work.c
:export:
HDMI Infoframes Helper Reference
================================
Strictly speaking this is not a DRM helper library but generally useable
by any driver interfacing with HDMI outputs like v4l or alsa drivers.
But it nicely fits into the overall topic of mode setting helper
libraries and hence is also included here.
.. kernel-doc:: include/linux/hdmi.h
:internal:
.. kernel-doc:: drivers/video/hdmi.c
:export:
Plane Helper Reference
======================
.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
:doc: overview
Tile group
----------
.. kernel-doc:: drivers/gpu/drm/drm_crtc.c
:doc: Tile group
Bridges
=======
Overview
--------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: overview
Default bridge callback sequence
--------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: bridge callbacks
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:export:
Panel Helper Reference
======================
.. kernel-doc:: include/drm/drm_panel.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_panel.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_panel.c
:doc: drm panel
Simple KMS Helper Reference
===========================
.. kernel-doc:: include/drm/drm_simple_kms_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_simple_kms_helper.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_simple_kms_helper.c
:doc: overview
此差异已折叠。
此差异已折叠。
===================
Userland interfaces
===================
The DRM core exports several interfaces to applications, generally
intended to be used through corresponding libdrm wrapper functions. In
addition, drivers export device-specific interfaces for use by userspace
drivers & device-aware applications through ioctls and sysfs files.
External interfaces include: memory mapping, context management, DMA
operations, AGP management, vblank control, fence management, memory
management, and output management.
Cover generic ioctls and sysfs layout here. We only need high-level
info, since man pages should cover the rest.
libdrm Device Lookup
====================
.. kernel-doc:: drivers/gpu/drm/drm_ioctl.c
:doc: getunique and setversion story
Primary Nodes, DRM Master and Authentication
============================================
.. kernel-doc:: drivers/gpu/drm/drm_auth.c
:doc: master and authentication
.. kernel-doc:: drivers/gpu/drm/drm_auth.c
:export:
.. kernel-doc:: include/drm/drm_auth.h
:internal:
Render nodes
============
DRM core provides multiple character-devices for user-space to use.
Depending on which device is opened, user-space can perform a different
set of operations (mainly ioctls). The primary node is always created
and called card<num>. Additionally, a currently unused control node,
called controlD<num> is also created. The primary node provides all
legacy operations and historically was the only interface used by
userspace. With KMS, the control node was introduced. However, the
planned KMS control interface has never been written and so the control
node stays unused to date.
With the increased use of offscreen renderers and GPGPU applications,
clients no longer require running compositors or graphics servers to
make use of a GPU. But the DRM API required unprivileged clients to
authenticate to a DRM-Master prior to getting GPU access. To avoid this
step and to grant clients GPU access without authenticating, render
nodes were introduced. Render nodes solely serve render clients, that
is, no modesetting or privileged ioctls can be issued on render nodes.
Only non-global rendering commands are allowed. If a driver supports
render nodes, it must advertise it via the DRIVER_RENDER DRM driver
capability. If not supported, the primary node must be used for render
clients together with the legacy drmAuth authentication procedure.
If a driver advertises render node support, DRM core will create a
separate render node called renderD<num>. There will be one render node
per device. No ioctls except PRIME-related ioctls will be allowed on
this node. Especially GEM_OPEN will be explicitly prohibited. Render
nodes are designed to avoid the buffer-leaks, which occur if clients
guess the flink names or mmap offsets on the legacy interface.
Additionally to this basic interface, drivers must mark their
driver-dependent render-only ioctls as DRM_RENDER_ALLOW so render
clients can use them. Driver authors must be careful not to allow any
privileged ioctls on render nodes.
With render nodes, user-space can now control access to the render node
via basic file-system access-modes. A running graphics server which
authenticates clients on the privileged primary/legacy node is no longer
required. Instead, a client can open the render node and is immediately
granted GPU access. Communication between clients (or servers) is done
via PRIME. FLINK from render node to legacy node is not supported. New
clients must not use the insecure FLINK interface.
Besides dropping all modeset/global ioctls, render nodes also drop the
DRM-Master concept. There is no reason to associate render clients with
a DRM-Master as they are independent of any graphics server. Besides,
they must work without any running master, anyway. Drivers must be able
to run without a master object if they support render nodes. If, on the
other hand, a driver requires shared state between clients which is
visible to user-space and accessible beyond open-file boundaries, they
cannot support render nodes.
VBlank event handling
=====================
The DRM core exposes two vertical blank related ioctls:
DRM_IOCTL_WAIT_VBLANK
This takes a struct drm_wait_vblank structure as its argument, and
it is used to block or request a signal when a specified vblank
event occurs.
DRM_IOCTL_MODESET_CTL
This was only used for user-mode-settind drivers around modesetting
changes to allow the kernel to update the vblank interrupt after
mode setting, since on many devices the vertical blank counter is
reset to 0 at some point during modeset. Modern drivers should not
call this any more since with kernel mode setting it is a no-op.
This second part of the GPU Driver Developer's Guide documents driver
code, implementation details and also all the driver-specific userspace
interfaces. Especially since all hardware-acceleration interfaces to
userspace are driver specific for efficiency and other reasons these
interfaces can be rather substantial. Hence every driver has its own
chapter.
此差异已折叠。
==================================
Linux GPU Driver Developer's Guide
==================================
.. toctree::
introduction
drm-internals
drm-mm
drm-kms
drm-kms-helpers
drm-uapi
i915
vga-switcheroo
此差异已折叠。
此差异已折叠。
此差异已折叠。
......@@ -13,6 +13,7 @@ Contents:
.. toctree::
:maxdepth: 2
gpu/index
Indices and tables
==================
......
......@@ -3865,7 +3865,7 @@ F: drivers/gpu/vga/
F: Documentation/devicetree/bindings/display/
F: Documentation/devicetree/bindings/gpu/
F: Documentation/devicetree/bindings/video/
F: Documentation/DocBook/gpu.*
F: Documentation/gpu/
F: include/drm/
F: include/uapi/drm/
......@@ -3917,6 +3917,7 @@ S: Supported
F: drivers/gpu/drm/i915/
F: include/drm/i915*
F: include/uapi/drm/i915_drm.h
F: Documentation/gpu/i915.rst
DRM DRIVERS FOR ATMEL HLCDC
M: Boris Brezillon <boris.brezillon@free-electrons.com>
......
此差异已折叠。
......@@ -187,12 +187,12 @@ int init_pipelines(struct device_queue_manager *dqm,
unsigned int get_first_pipe(struct device_queue_manager *dqm);
unsigned int get_pipes_num(struct device_queue_manager *dqm);
extern inline unsigned int get_sh_mem_bases_32(struct kfd_process_device *pdd)
static inline unsigned int get_sh_mem_bases_32(struct kfd_process_device *pdd)
{
return (pdd->lds_base >> 16) & 0xFF;
}
extern inline unsigned int
static inline unsigned int
get_sh_mem_bases_nybble_64(struct kfd_process_device *pdd)
{
return (pdd->lds_base >> 60) & 0x0E;
......
此差异已折叠。
......@@ -189,7 +189,6 @@ static struct drm_driver armada_drm_driver = {
.load = armada_drm_load,
.lastclose = armada_drm_lastclose,
.unload = armada_drm_unload,
.set_busid = drm_platform_set_busid,
.get_vblank_counter = drm_vblank_no_hw_counter,
.enable_vblank = armada_drm_enable_vblank,
.disable_vblank = armada_drm_disable_vblank,
......
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
此差异已折叠。
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册