As requested in Documentation/gpu/todo.rst, replace driver calls to
drm_modeset_lock_all() with DRM_MODESET_LOCK_ALL_BEGIN() and
DRM_MODESET_LOCK_ALL_END()
While the previous commit was a simple "search and replace", this time I
had to do a bit of refactoring as only one call to
DRM_MODESET_LOCK_ALL_BEGIN() is allowed inside one same function.
Signed-off-by: Fernando Ramos <greenfoo@u92.eu>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924064324.229457-14-greenfoo@u92.eu
This can be used to create a separate DRM file description, thus
creating a new GEM handle namespace.
My use-case is wlroots. The library splits responsibilities between
separate components: the GBM allocator creates buffers, the GLES2
renderer uses EGL to import them and render to them, the DRM
backend imports the buffers and displays them. wlroots has a
modular architecture, and any of these components can be swapped
and replaced with something else. For instance, the pipeline can
be set up so that the DRM dumb buffer allocator is used instead of
GBM and the Pixman renderer is used instead of GLES2. Library users
can also replace any of these components with their own custom one.
DMA-BUFs are used to pass buffer references across components. We
could use GEM handles instead, but this would result in pain if
multiple GPUs are in use: wlroots copies buffers across GPUs as
needed. Importing a GEM handle created on one GPU into a completely
different GPU will blow up (fail at best, mix unrelated buffers
otherwise).
Everything is fine if all components use Mesa. However, this isn't
always desirable. For instance when running with DRM dumb buffers
and the Pixman software renderer it's unfortunate to depend on GBM
in the DRM backend just to turn DMA-BUFs into FB IDs. GBM loads
Mesa drivers to perform an action which has nothing driver-specific.
Additionally, drivers will fail the import if the 3D engine can't
use the imported buffer, for instance amdgpu will refuse to import
DRM dumb buffers [1]. We might also want to be running with a Vulkan
renderer and a Vulkan allocator in the future, and GBM wouldn't be
welcome in this setup.
To address this, GBM can be side-stepped in the DRM backend, and
can be replaced with drmPrimeFDToHandle calls. However because of
GEM handle reference counting issues, care must be taken to avoid
double-closing the same GEM handle. In particular, it's not
possible to share a DRM FD with GBM or EGL and perform some
drmPrimeFDToHandle calls manually.
So wlroots needs to re-open the DRM FD to create a new GEM handle
namespace. However there's no guarantee that the file-system
permissions will be set up so that the primary FD can be opened
by the compsoitor. On modern systems seatd or logind is a privileged
process responsible for doing this, and other processes aren't
expected to do it. For historical reasons systemd still allows
physically logged in users to open primary DRM nodes, but this
doesn't work on non-systemd setups and it's desirable to lock
them down at some point.
Some might suggest to open the render node instead of re-opening
the primary node. However some systems don't have a render node
at all (e.g. no GPU, or a split render/display SoC).
Solutions to this issue have been discussed in [2]. One solution
would be to open the magic /proc/self/fd/<fd> file, but it's a
Linux-specific hack (wlroots supports BSDs too). Another solution
is to add support for re-opening a DRM primary node to seatd/logind,
but they don't support it now and really haven't been designed for
this (logind would need to grow a completely new API, because it
assumes unique dev_t IDs). Also this seems like pushing down a
kernel limitation to user-space a bit too hard.
Another solution is to allow creating empty DRM leases. The lessee
FD would have its own GEM handle namespace, so wouldn't conflict
wth GBM/EGL. It would have the master bit set, but would be able
to manage zero resources. wlroots doesn't intend to share this FD
with any other process.
All in all IMHO that seems like a pretty reasonable solution to the
issue at hand.
Note, I've discussed with Jonas Ådahl and Mutter plans to adopt a
similar design in the future.
Example usage in wlroots is available at [3]. IGT test available
at [4].
[1]: https://github.com/swaywm/wlroots/issues/2916
[2]: https://gitlab.freedesktop.org/mesa/drm/-/merge_requests/110
[3]: https://github.com/swaywm/wlroots/pull/3158
[4]: https://patchwork.freedesktop.org/series/94323/
Signed-off-by: Simon Ser <contact@emersion.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Daniel Stone <daniels@collabora.com>
Cc: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Cc: Michel Dänzer <michel@daenzer.net>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Keith Packard <keithp@keithp.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Dave Airlie <airlied@redhat.com>
Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210903130000.1590-2-contact@emersion.fr
Daniel pointed me towards this function and there are multiple obvious problems
in the implementation.
First of all the retry loop is not working as intended. In general the retry
makes only sense if you grab the reference first and then check the sequence
values.
Then we should always also wait for the exclusive fence.
It's also good practice to keep the reference around when installing callbacks
to fences you don't own.
And last the whole implementation was unnecessary complex and rather hard to
understand which could lead to probably unexpected behavior of the IOCTL.
Fix all this by reworking the implementation from scratch. Dropping the
whole RCU approach and taking the lock instead.
Only mildly tested and needs a thoughtful review of the code.
Pushing through drm-misc-next to avoid merge conflicts and give the code
another round of testing.
v2: fix the reference counting as well
v3: keep the excl fence handling as is for stable
v4: back to testing all fences, drop RCU
v5: handle in and out separately
v6: add missing clear of events
v7: change coding style as suggested by Michel, drop unused variables
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Michel Dänzer <mdaenzer@redhat.com>
CC: stable@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210720131110.88512-1-christian.koenig@amd.com
In commit:
commit 667a50db04
Author: Thomas Hellstrom <thellstrom@vmware.com>
Date: Fri Jan 3 11:17:18 2014 +0100
drm/ttm: Refuse to fault (prime-) imported pages
we introduced the restriction that imported pages should not be directly
mappable through TTM(this also extends to userptr). In the next patch we
want to introduce a shmem_tt backend, which should follow all the
existing rules with TTM_PAGE_FLAG_EXTERNAL, since it will need to handle
swapping itself, but with the above mapping restriction lifted.
v2(Christian):
- Don't OR together EXTERNAL and EXTERNAL_MAPPABLE in the definition
of EXTERNAL_MAPPABLE, just leave it the caller to handle this
correctly, otherwise we might encounter subtle issues.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210929132629.353541-3-matthew.auld@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>
In commit:
commit 58aa6622d3
Author: Thomas Hellstrom <thellstrom@vmware.com>
Date: Fri Jan 3 11:47:23 2014 +0100
drm/ttm: Correctly set page mapping and -index members
we started setting the page->mapping and page->index to point to the
virtual address space, if the pages were faulted with TTM. Apparently
this was needed for core-mm to able to reverse lookup the virtual
address given the struct page, and potentially unmap it from the page
tables. However as pointed out by Thomas, since we are now using
PFN_MAP, instead of say PFN_MIXED, this should no longer be the case.
There was also apparently some usecase in vmwgfx which needed this for
dirty tracking, but that also doesn't appear to be the case anymore, as
pointed out by Thomas.
We still need keep the page->mapping for now, since that is still needed
for different reasons, but we try to address that in the next patch.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210927114114.152310-2-matthew.auld@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>
Similar to DRM_VMW_EVENT_FENCE_SIGNALED. Sends a pollable event
to the DRM file descriptor when a fence on a specific ring is
signaled.
One difference is the event is not exposed via the UAPI -- this is
because host responses are on a shared memory buffer of type
BLOB_MEM_GUEST [this is the common way to receive responses with
virtgpu]. As such, there is no context specific read(..)
implementation either -- just a poll(..) implementation.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Nicholas Verne <nverne@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-12-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
For the Sommelier guest Wayland proxy, it's desirable for the
DRM fd to be pollable in response to an host compositor event.
This can also be used by the 3D driver to poll events on a CPU
timeline.
This enables the DRM fd associated with a particular 3D context
to be polled independent of KMS events. The parameter
VIRTGPU_CONTEXT_PARAM_POLL_RINGS_MASK specifies the pollable
rings.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Nicholas Verne <nverne@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-11-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
These were defined in the previous commit. We'll need these
parameters when allocating a dma_fence. The use case for this
is multiple synchronizations timelines.
The maximum number of timelines per 3D instance will be 32. Usually,
only 2 are needed -- one for CPU commands, and another for GPU
commands.
As such, we'll need to specify these parameters when allocating a
dma_fence.
vgdev->fence_drv.context is the "default" fence context for 2D mode
and old userspace.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-8-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Each fence should be associated with a [fence ID, fence_context,
seqno]. The seqno number is just the fence id.
To get the fence context, we add the ring_idx to the 3D context's
base_fence_ctx. The ring_idx is between 0 and 31, inclusive.
Each 3D context will have it's own base_fence_ctx. The ring_idx will
be emitted to host userspace, when emit_fence_info is true.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-7-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This implements the context initialization ioctl. A list of params
is passed in by userspace, and kernel driver validates them. The
only currently supported param is VIRTGPU_CONTEXT_PARAM_CAPSET_ID.
If the context has already been initialized, -EEXIST is returned.
This happens after Linux userspace does dumb_create + followed by
opening the Mesa virgl driver with the same virtgpu instance.
However, for most applications, 3D contexts will be explicitly
initialized when the feature is available.
Signed-off-by: Anthoine Bourgeois <anthoine.bourgeois@gmail.com>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-6-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This change allows creating contexts of depending on set of
context parameters. The meaning of each of the parameters
is listed below:
1) VIRTGPU_CONTEXT_PARAM_CAPSET_ID
This determines the type of a context based on the capability set
ID. For example, the current capsets:
VIRTIO_GPU_CAPSET_VIRGL
VIRTIO_GPU_CAPSET_VIRGL2
define a Gallium, TGSI based "virgl" context. We only need 1 capset
ID per context type, though virgl has two due a bug that has since
been fixed.
The use case is the "gfxstream" rendering library and "venus"
renderer.
gfxstream doesn't do Gallium/TGSI translation and mostly relies on
auto-generated API streaming. Certain users prefer gfxstream over
virgl for GLES on GLES emulation. {gfxstream vk}/{venus} are also
required for Vulkan emulation. The maximum capset ID is 63.
The goal is for guest userspace to choose the optimal context type
depending on the situation/hardware.
2) VIRTGPU_CONTEXT_PARAM_NUM_RINGS
This tells the number of independent command rings that the context
will use. This value may be zero and is inferred to be zero if
VIRTGPU_CONTEXT_PARAM_NUM_RINGS is not passed in. This is for backwards
compatibility for virgl, which has one big giant command ring for all
commands.
The maxiumum number of rings is 64. In practice, multi-queue or
multi-ring submission is used for powerful dGPUs and virtio-gpu
may not be the best option in that case (see PCI passthrough or
rendernode forwarding).
3) VIRTGPU_CONTEXT_PARAM_POLL_RING_IDX_MASK
This is a mask of ring indices for which the DRM fd is pollable.
For example, if VIRTGPU_CONTEXT_PARAM_NUM_RINGS is 2, then the mask
may be:
[ring idx] | [1 << ring_idx] | final mask
-------------------------------------------
0 1 1
1 2 3
The "Sommelier" guest Wayland proxy uses this to poll for events
from the host compositor.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Acked-by: Nicholas Verne <nverne@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-3-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This feature allows for each virtio-gpu 3D context to be created
with a "context_init" variable. This variable can specify:
- the type of protocol used by the context via the capset id.
This is useful for differentiating virgl, gfxstream, and venus
protocols by host userspace.
- other things in the future, such as the version of the context.
In addition, each different context needs one or more timelines, so
for example a virgl context's waiting can be independent on a
gfxstream context's waiting.
VIRTIO_GPU_FLAG_INFO_RING_IDX is introduced to specific to tell the
host which per-context command ring (or "hardware queue", distinct
from the virtio-queue) the fence should be associated with.
The new capability sets (gfxstream, venus etc.) are only defined in
the virtio-gpu spec and not defined in the header.
Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Lingfeng Yang <lfy@google.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210921232024.817-2-gurchetansingh@chromium.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The drm_helper_hpd_irq_event() documentation states that this function
is "useful for drivers which can't or don't track hotplug interrupts for
each connector." and that "Drivers which support hotplug interrupts for
each connector individually and which have a more fine-grained detect
logic should bypass this code and directly call
drm_kms_helper_hotplug_event()". This is thus what we ended-up doing.
However, what this actually means, and is further explained in the
drm_kms_helper_hotplug_event() documentation, is that
drm_kms_helper_hotplug_event() should be called by drivers that can
track the connection status change, and if it has changed we should call
that function.
This underlying expectation we failed to provide is that the caller of
drm_kms_helper_hotplug_event() should call drm_helper_probe_detect() to
probe the new status of the connector.
Since we didn't do it, it meant that even though we were sending the
notification to user-space and the DRM clients that something changed we
never probed or updated our internal connector status ourselves.
This went mostly unnoticed since the detect callback usually doesn't
have any side-effect. Also, if we were using the DRM fbdev emulation
(which is a DRM client), or any user-space application that can deal
with hotplug events, chances are they would react to the hotplug event
by probing the connector status eventually.
However, now that we have to enable the scrambler in detect() if it was
enabled it has a side effect, and an application such as Kodi or
modetest doesn't deal with hotplug events. This resulted with a black
screen when Kodi or modetest was running when a screen was disconnected
and then reconnected, or switched off and on.
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210914101724.266570-3-maxime@cerno.tech
The drm_helper_hpd_irq_event() function is iterating over all the
connectors when an hotplug event is detected.
During that iteration, it will call each connector detect function and
figure out if its status changed.
Finally, if any connector changed, it will notify the user-space and the
clients that something changed on the DRM device.
This is supposed to be used for drivers that don't have a hotplug
interrupt for individual connectors. However, drivers that can use an
interrupt for a single connector are left in the dust and can either
reimplement the logic used during the iteration for each connector or
use that helper and iterate over all connectors all the time.
Since both are suboptimal, let's create a helper that will only perform
the status detection on a single connector.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210914101724.266570-2-maxime@cerno.tech
MSM is one of the few drivers which won't even compile
test on !ARM platforms.
Looking into this a bit more it turned out that there is
actually not that much missing to at least let the driver
compile on x86 as well.
So this patch replaces the use of phys_to_page() with the
open coded version and provides a dummy for of_drm_find_bridge().
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924071759.22659-2-christian.koenig@amd.com
Due to a simple typo (apparently I can't count. It goes 0, 1, 2 and
not 0, 2, 3) we were getting a kernel doc warning that looked like
this:
include/drm/drm_edid.h:530: warning:
Function parameter or member 'vend_chr_1' not described in 'drm_edid_encode_panel_id'
include/drm/drm_edid.h:530: warning:
Excess function parameter 'vend_chr_3' description in 'drm_edid_encode_panel_id'
Fix it.
Fixes: 7d1be0a09f ("drm/edid: Fix EDID quirk compile error on older compilers")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210927074104.1.Ibf22f2a0b75287a5d636c0570c11498648bf61c6@changeid
