Christian König [Tue, 15 Jun 2021 13:10:03 +0000 (15:10 +0200)]
dma-buf: add dma_resv_for_each_fence_unlocked v8
Abstract the complexity of iterating over all the fences
in a dma_resv object.
The new loop handles the whole RCU and retry dance and
returns only fences where we can be sure we grabbed the
right one.
v2: fix accessing the shared fences while they might be freed,
improve kerneldoc, rename _cursor to _iter, add
dma_resv_iter_is_exclusive, add dma_resv_iter_begin/end
v3: restructor the code, move rcu_read_lock()/unlock() into the
iterator, add dma_resv_iter_is_restarted()
v4: fix NULL deref when no explicit fence exists, drop superflous
rcu_read_lock()/unlock() calls.
v5: fix typos in the documentation
v6: fix coding error when excl fence is NULL
v7: one more logic fix
v8: fix index check in dma_resv_iter_is_exclusive()
In the commit 1428c594df89 ("drm/edid: Break out reading block 0 of
the EDID") I broke out reading the base block of the EDID to its own
function. Unfortunately, when I did that I messed up the handling when
drm_edid_is_zero() indicated that we had an EDID that was all 0x00 or
when we went through 4 loops and didn't get a valid EDID. Specifically
I needed to pass the broken EDID to connector_bad_edid() but now I was
passing an error-pointer.
Let's re-jigger things so we can pass the bad EDID in properly.
Fixes: 1428c594df89 ("drm/edid: Break out reading block 0 of the EDID") Reported-by: kernel test robot <oliver.sang@intel.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patchwork.freedesktop.org/patch/msgid/20211004092100.1.Ic90a5ebd44c75db963112be167a03cc96f9fb249@changeid
Using the generic extension from the previous patch, a specific multisync
extension enables more than one in/out binary syncobj per job submission.
Arrays of syncobjs are set in struct drm_v3d_multisync, that also cares
of determining the stage for sync (wait deps) according to the job
queue.
v2:
- subclass the generic extension struct (Daniel)
- simplify adding dependency conditions to make understandable (Iago)
v3:
- fix conditions to consider single or multiples in/out_syncs (Iago)
- remove irrelevant comment (Iago)
Add support to attach generic extensions on job submission. This patch
is third prep work to enable multiple syncobjs on job submission. With
this work, when the job submission interface needs to be extended to
accommodate a new feature, we will use a generic extension struct where
an id determines the data type to be pointed. The first application is
to enable multiples in/out syncobj (next patch), but the base is
already done for future features. Therefore, to attach a new feature,
a specific extension struct should subclass drm_v3d_extension and
update the list of extensions in a job submission.
v2:
- remove redundant elements to subclass struct (Daniel)
Move job memory allocation to v3d_job_init function. This aim to facilitate
error handling in job initialization, since cleanup steps are similar for
all (struct v3d_job)-based types of job involved in a command submission.
To generalize v3d_job_init(), this change takes into account that all job
structs have the first element a struct v3d_job (bin, render, tfu, csd) or
it is a v3d_job itself (clean_job) for pointer casting.
v3:
- explicitly init job as NULL (Iago)
- fix pm failure handling on v3_job_init (Iago)
drm/v3d: decouple adding job dependencies steps from job init
Prep work to enable a job to wait for more than one syncobj before
start. Also get rid of old checkpatch warnings in the v3d_gem file.
No functional changes.
For the brave new world of bridges not creating their own connectors, we
need to implement the max clock limitation via bridge->mode_valid()
instead of connector->mode_valid().
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()
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()
Fernando Ramos [Fri, 24 Sep 2021 06:43:20 +0000 (08:43 +0200)]
drm/i915: cleanup: drm_modeset_lock_all() --> DRM_MODESET_LOCK_ALL_BEGIN() part 2
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.
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()
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()
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()
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()
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()
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()
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()
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()
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()
As requested in Documentation/gpu/todo.rst, replace the boilerplate code
surrounding drm_modeset_lock_all_ctx() with DRM_MODESET_LOCK_ALL_BEGIN()
and DRM_MODESET_LOCK_ALL_END()
As requested in Documentation/gpu/todo.rst, replace the boilerplate code
surrounding drm_modeset_lock_all_ctx() with DRM_MODESET_LOCK_ALL_BEGIN()
and DRM_MODESET_LOCK_ALL_END()
As requested in Documentation/gpu/todo.rst, replace the boilerplate code
surrounding drm_modeset_lock_all_ctx() with DRM_MODESET_LOCK_ALL_BEGIN()
and DRM_MODESET_LOCK_ALL_END()
Simon Ser [Fri, 3 Sep 2021 13:00:32 +0000 (13:00 +0000)]
drm/lease: allow empty leases
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].
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
Christian König [Tue, 15 Jun 2021 11:12:33 +0000 (13:12 +0200)]
dma-buf: fix and rework dma_buf_poll v7
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
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.
Matthew Auld [Wed, 29 Sep 2021 13:26:28 +0000 (14:26 +0100)]
drm/ttm: add some kernel-doc for TTM_TT_FLAG_*
Move it to inline kernel-doc, otherwise we can't add empty lines it
seems. Also drop the kernel-doc for pages_list, which doesn't seem to
exist.
v2(Christian):
- Add a note that FLAG_SWAPPED shouldn't need to be touched by drivers.
- Mention what FLAG_POPULATED does.
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/20210929132629.353541-2-matthew.auld@intel.com Signed-off-by: Christian König <christian.koenig@amd.com>
Matthew Auld [Wed, 29 Sep 2021 13:26:27 +0000 (14:26 +0100)]
drm/ttm: s/FLAG_SG/FLAG_EXTERNAL/
It covers more than just ttm_bo_type_sg usage, like with say dma-buf,
since one other user is userptr in amdgpu, and in the future we might
have some more. Hence EXTERNAL is likely a more suitable name.
v2(Christian):
- Rename these to TTM_TT_FLAGS_*
- Fix up all the holes in the flag values
Suggested-by: Christian König <christian.koenig@amd.com> Signed-off-by: Matthew Auld <matthew.auld@intel.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Christian König <christian.koenig@amd.com> Acked-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210929132629.353541-1-matthew.auld@intel.com Signed-off-by: Christian König <christian.koenig@amd.com>
Matthew Auld [Mon, 27 Sep 2021 11:41:05 +0000 (12:41 +0100)]
drm/ttm: remove TTM_PAGE_FLAG_NO_RETRY
No longer used it seems.
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/20210927114114.152310-4-matthew.auld@intel.com Signed-off-by: Christian König <christian.koenig@amd.com>
Matthew Auld [Mon, 27 Sep 2021 11:41:04 +0000 (12:41 +0100)]
drm/ttm: move ttm_tt_{add, clear}_mapping into amdgpu
Now that setting page->index shouldn't be needed anymore, we are just
left with setting page->mapping, and here it looks like amdgpu is the
only user, where pointing the page->mapping at the dev_mapping is used
to verify that the pages do indeed belong to the device, if userspace
later tries to touch them.
v2(Christian):
- Drop the functions altogether and just inline modifying
the page->mapping
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/20210927114114.152310-3-matthew.auld@intel.com Signed-off-by: Christian König <christian.koenig@amd.com>
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>
we added the vm_access hook, where we also directly call tt_swapin for
some reason. If something is swapped-out then the ttm_tt must also be
unpopulated, and since access_kmap should also call tt_populate, if
needed, then swapping-in will already be handled there.
If anything, calling tt_swapin directly here would likely always fail
since the tt->pages won't yet be populated, or worse since the tt->pages
array is never actually cleared in unpopulate this might lead to a nasty
uaf.
Fixes: ee167968b823 ("drm/ttm: Implement vm_operations_struct.access v2") 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: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210927114114.152310-1-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.
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.
drm/virtio: implement context init: allocate an array of fence contexts
We don't want fences from different 3D contexts (virgl, gfxstream,
venus) to be on the same timeline. With explicit context creation,
we can specify the number of ring each context wants.
drm/virtio: implement context init: stop using drv->context when creating fence
The plumbing is all here to do this. Since we always use the
default fence context when allocating a fence, this makes no
functional difference.
We can't process just the largest fence id anymore, since it's
it's associated with different timelines. It's fine for fence_id
260 to signal before 259. As such, process each fence_id
individually.
drm/virtio: implement context init: plumb {base_fence_ctx, ring_idx} to virtio_gpu_fence_alloc
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.
drm/virtio: implement context init: support init ioctl
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.
drm/virtio: implement context init: track valid capabilities in a mask
The valid capability IDs are between 1 to 63, and defined in the
virtio gpu spec. This is used for error checking the subsequent
patches. We're currently only using 2 capability IDs, so this
should be plenty for the immediate future.
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:
virtio-gpu api: multiple context types with explicit initialization
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.
drm/panel: support for BOE and INX video mode panel
Support for these two panels fits in nicely with the existing
panel-boe-tv101wum-nl6 driver as suggested by Sam [1].
This is an incell IC, TDDI use time division multiplexing.
Init code effect touch sensing.The main things
we needed to handle were:
a) These panels need slightly longer delays in two places. Since these
new delays aren't much longer, let's just unconditionally increase
them for the driver.
b) These panel use video BURST mode
drm/panel: boe-tv101wum-nl6: Support enabling a 3.3V rail
The auo,b101uan08.3 panel (already supported by this driver) has
a 3.3V rail that needs to be turned on. For previous users of
this panel this voltage was directly output by pmic. On a new
user (the not-yet-upstream sc7180-trogdor-mrbland board) we need
to turn the 3.3V rail on. Add support in the driver for this.
dt-bindings: drm/panel: boe-tv101wum-nl6: Support enabling a 3.3V rail
The auo,b101uan08.3 panel (already supported by this driver) has
a 3.3V rail that needs to be turned on. For previous users of
this panel this voltage was directly output by pmic. On a new
user (the not-yet-upstream sc7180-trogdor-mrbland board) we need
to turn the 3.3V rail on.
Maxime Ripard [Tue, 14 Sep 2021 10:17:24 +0000 (12:17 +0200)]
drm/vc4: hdmi: Actually check for the connector status in hotplug
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.
Maxime Ripard [Tue, 14 Sep 2021 10:17:23 +0000 (12:17 +0200)]
drm/probe-helper: Create a HPD IRQ event helper for a single connector
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.
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'
Douglas Anderson [Tue, 21 Sep 2021 15:28:01 +0000 (08:28 -0700)]
drm/print: Add deprecation notes to DRM_...() functions
It's hard for someone (like me) who's not following closely to know
what the suggested best practices are for error printing in DRM
drivers. Add some hints to the header file.
In general, my understanding is that:
* When possible we should be using a `struct drm_device` for logging
and recent patches have tried to make it more possible to access a
relevant `struct drm_device` in more places.
* For most cases when we don't have a `struct drm_device`, we no
longer bother with DRM-specific wrappers on the dev_...() functions
or pr_...() functions and just encourage drivers to use the normal
functions.
* For debug-level functions where we might want filtering based on a
category we'll still have DRM-specific wrappers, but we'll only
support passing a `struct drm_device`, not a `struct
device`. Presumably most of the cases where we want the filtering
are messages that happen while the system is in a normal running
state (AKA not during probe time) and we should have a `struct
drm_device` then. If we absolutely can't get a `struct drm_device`
then these functions begrudgingly accept NULL for the `struct
drm_device` and hopefully the awkwardness of having to manually pass
NULL will keep people from doing this unless absolutely necessary.
Douglas Anderson [Fri, 24 Sep 2021 14:53:21 +0000 (07:53 -0700)]
drm/edid: Fix EDID quirk compile error on older compilers
Apparently some compilers [1] cannot handle doing math on dereferenced
string constants at compile time. This has led to reports [2] of
compile errors like:
In file included from drivers/gpu/drm/drm_edid.c:42:0:
./include/drm/drm_edid.h:525:2: error: initializer element is not constant
((((u32)((vend)[0]) - '@') & 0x1f) << 26 | \
Go back to the syntax I used in v4 of the patch series [3] that added
this code instead of what landed (v5). This syntax is slightly uglier
but should be much more compatible with varied compilers.
Fixes: 36e319403921 ("drm/edid: Allow querying/working with the panel ID from the EDID") Reported-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> Reported-by: Srikanth Myakam <smyakam@microsoft.com> Signed-off-by: Douglas Anderson <dianders@chromium.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Acked-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20210924075317.1.I1e58d74d501613f1fe7585958f451160d11b8a98@changeid
Maxime Ripard [Fri, 10 Sep 2021 10:11:57 +0000 (12:11 +0200)]
drm/mipi-dsi: Create devm device registration
Devices that take their data through the MIPI-DSI bus but are controlled
through a secondary bus like I2C have to register a secondary device on
the MIPI-DSI bus through the mipi_dsi_device_register_full() function.
At removal or when an error occurs, that device needs to be removed
through a call to mipi_dsi_device_unregister().
Let's create a device-managed variant of the registration function that
will automatically unregister the device at unbind.
Maxime Ripard [Fri, 10 Sep 2021 10:11:56 +0000 (12:11 +0200)]
drm/bridge: Document the probe issue with MIPI-DSI bridges
Interactions between bridges, panels, MIPI-DSI host and the component
framework are not trivial and can lead to probing issues when
implementing a display driver. Let's document the various cases we need
too consider, and the solution to support all the cases.
drm/gma500: Embed struct drm_device in struct drm_psb_private
Embed struct drm_device in struct drm_psb_private. Replace the use
of dev_private by an upcast operation. Switch to managed release of
struct drm_psb_private.
drm/gma500: Replace references to dev_private with helper function
Replace most references to struct drm_device.dev_private with the new
helper function to_drm_psb_private(). The only references left are in
assignments and the helper itself.
Add devm_arch_io_reserve_memtype_wc() as managed wrapper around
arch_io_reserve_memtype_wc(). Useful for several graphics drivers
that set framebuffer memory to write combining.
Add devm_arch_phys_wc_add() as managed wrapper around arch_phys_wc_add().
Useful for several graphics drivers that set framebuffer memory to write
combining.
Maxime Ripard [Fri, 17 Sep 2021 18:09:25 +0000 (20:09 +0200)]
drm/bridge: Move devm_drm_of_get_bridge to bridge/panel.c
By depending on devm_drm_panel_bridge_add(), devm_drm_of_get_bridge()
introduces a circular dependency between the modules drm (where
devm_drm_of_get_bridge() ends up) and drm_kms_helper (where
devm_drm_panel_bridge_add() is).
Fix this by moving devm_drm_of_get_bridge() to bridge/panel.c and thus
drm_kms_helper.
Fixes: 336c3299149d ("drm/bridge: Add a function to abstract away panels") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Maxime Ripard <maxime@cerno.tech> Tested-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20210917180925.2602266-1-maxime@cerno.tech
projects / kernel.git / log