Chris Wilson [Mon, 14 Jan 2019 14:21:10 +0000 (14:21 +0000)]
drm/i915: Markup paired operations on wakerefs
The majority of runtime-pm operations are bounded and scoped within a
function; these are easy to verify that the wakeref are handled
correctly. We can employ the compiler to help us, and reduce the number
of wakerefs tracked when debugging, by passing around cookies provided
by the various rpm_get functions to their rpm_put counterpart. This
makes the pairing explicit, and given the required wakeref cookie the
compiler can verify that we pass an initialised value to the rpm_put
(quite handy for double checking error paths).
For regular builds, the compiler should be able to eliminate the unused
local variables and the program growth should be minimal. Fwiw, it came
out as a net improvement as gcc was able to refactor rpm_get and
rpm_get_if_in_use together,
v2: Just s/rpm_put/rpm_put_unchecked/ everywhere, leaving the manual
mark up for smaller more targeted patches.
v3: Mention the cookie in Returns
Chris Wilson [Mon, 14 Jan 2019 14:21:09 +0000 (14:21 +0000)]
drm/i915: Track all held rpm wakerefs
Everytime we take a wakeref, record the stack trace of where it was
taken; clearing the set if we ever drop back to no owners. For debugging
a rpm leak, we can look at all the current wakerefs and check if they
have a matching rpm_put.
v2: Use skip=0 for unwinding the stack as it appears our noinline
function doesn't appear on the stack (nor does save_stack_trace itself!)
v3: Allow rpm->debug_count to disappear between inspections and so
avoid calling krealloc(0) as that may return a ZERO_PTR not NULL! (Mika)
v4: Show who last acquire/released the runtime pm
Noralf Trønnes [Wed, 28 Nov 2018 21:27:10 +0000 (22:27 +0100)]
drm/mxsfb: Use drm_fbdev_generic_setup()
The CMA helper is already using the drm_fb_helper_generic_probe part of
the generic fbdev emulation. This patch makes full use of the generic
fbdev emulation by using its drm_client callbacks. This means that
drm_mode_config_funcs->output_poll_changed and drm_driver->lastclose are
now handled by the emulation code. Additionally fbdev unregister happens
automatically on drm_dev_unregister().
The drm_fbdev_generic_setup() call is put after drm_dev_register() in the
driver. This is done to highlight the fact that fbdev emulation is an
internal client that makes use of the driver, it is not part of the
driver as such. If fbdev setup fails, an error is printed, but the driver
succeeds probing.
Noralf Trønnes [Wed, 28 Nov 2018 21:27:09 +0000 (22:27 +0100)]
drm/hisilicon/kirin: Use drm_fbdev_generic_setup()
The CMA helper is already using the drm_fb_helper_generic_probe part of
the generic fbdev emulation. This patch makes full use of the generic
fbdev emulation by using its drm_client callbacks. This means that
drm_mode_config_funcs->output_poll_changed and drm_driver->lastclose are
now handled by the emulation code. Additionally fbdev unregister happens
automatically on drm_dev_unregister().
The drm_fbdev_generic_setup() call is put after drm_dev_register() in the
driver. This is done to highlight the fact that fbdev emulation is an
internal client that makes use of the driver, it is not part of the
driver as such. If fbdev setup fails, an error is printed, but the driver
succeeds probing.
struct kirin_drm_private can be removed now that driver doesn't have to
store the fbdev pointer.
Sam Ravnborg [Sat, 12 Jan 2019 19:32:44 +0000 (20:32 +0100)]
drm: move drm_can_sleep() to drm_util.h
Move drm_can_sleep() out of drmP.h to allow users
to get rid of the drmP.h include.
There was no header file that was a good match for this helper function.
So add this to drm_util with the relevant includes.
Add include of drm_util.h to all users.
v2:
- Update comments to use kernel-doc style (Daniel)
- Add FIXME to drm_can_sleep and add note that this
function should not be used in new code (Daniel)
Laurent Pinchart [Thu, 27 Dec 2018 09:26:56 +0000 (11:26 +0200)]
drm: rcar-du: Remove inclusion of drmP.h
The DRM kernel API used to be defined in a handful of headers, pulled in
through drmP.h. It has since been split in multiple headers for the
different DRM components, and drmP.h turned into a legacy header that
just pulls in most of the DRM kernel API (and a large number of other
miscellaneous kernel headers).
In order to speed up compilation, replace inclusion of drmP.h with only
the required headers. It turns out that the rcar-du-drm driver already
includes most of the necessary headers, so the change is simple.
While at it, remove unneeded inclusion of other headers, and unneeded
forward declarations of structures.
Laurent Pinchart [Sat, 24 Nov 2018 22:17:39 +0000 (00:17 +0200)]
drm: rcar-du: Disable unused DPAD outputs
DU channels are routed to DPAD outputs in an SoC-dependent way. The
routing can be fixed (e.g. DU3 to DPAD0 on H3) or configurable (e.g. DU0
or DU1 to DPAD0 on D3/E3). The hardware offers no option to disconnect
DPAD outputs, which are thus always driven by a DU channel.
On SoCs that have less DU channels than DU outputs, such as D3 and E3,
the DPAD output is always driven when all channels are in use by other
outputs (such as the internal LVDS and HDMI encoders). This creates an
unwanted clone on the DPAD output.
However, the parallel output of the DU channels routed to DPAD can be
set to fixed levels in the DU channels themselves through the DOFLR
group register. Use this to turn the DPAD on or off by driving fixed
signals at the output of any DU channel not routed to a DPAD output.
This doesn't affect the DU output signals going to other outputs.
Laurent Pinchart [Sat, 24 Nov 2018 18:19:52 +0000 (20:19 +0200)]
drm: rcar-du: Move CRTC outputs bitmask to private CRTC state
The rcar_du_crtc outputs field stores a bitmask of the outputs driven by
the CRTC. This changes based on the configuration requested by
userspace, and is used for the sole purpose of configuring the hardware.
The field thus belongs to the CRTC state. Move it to the
rcar_du_crtc_state structure.
As a result the rcar_du_crtc_route_output() function loses most of its
purpose. In order to remove it, move dpad0_source calculation to
rcar_du_atomic_commit_tail(), until the field gets moved to a state
structure. In order to simplify the rcar_du_group_set_routing()
implementation, we also store the DPAD1 source in a new dpad1_source
field which will move to a state structure with dpad0_source.
Laurent Pinchart [Sat, 24 Nov 2018 17:57:17 +0000 (19:57 +0200)]
drm: rcar-du: Replace EXT_CTRL_REGS feature flag with generation check
The RCAR_DU_FEATURE_EXT_CTRL_REGS feature flag is missing for H1 only,
which is a first generation device, not a second generation device as
reported in the device information table. Fix the H1 generation and use
generation checks to replace the feature flag.
Fabrizio Castro [Thu, 13 Dec 2018 20:23:36 +0000 (20:23 +0000)]
drm: rcar-du: lvds: add R8A774C0 support
The LVDS implementation on the RZ/G2E (a.k.a. R8A774C0) is very similar
to the one found on R-Car E3 (a.k.a. R8A77990), therefore add RZ/G2E
LVDS support to the LVDS encoder driver in a similar fashion to what is
done for R-Car E3.
drm: rcar-du: Convert live DT patches to sugar syntax
Using overlay sugar syntax makes the DTS files easier to read (and
write).
Overlay syntactic sugar for generating target-path fragments is
supported by the version of dtc supplied with the kernel since commit 50aafd60898a8b3e ("scripts/dtc: Update to upstream version v1.4.6-21-g84e414b0b5bc").
YueHaibing [Mon, 17 Dec 2018 09:18:30 +0000 (17:18 +0800)]
drm/shmob: Fix return value check in shmob_drm_probe
In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().
drm: bridge: Constify mode arguments to bridge .mode_set() operation
The mode and ajusted_mode passed to the bridge .mode_set() operation
should never be modified by the bridge (and are not in any of the
existing bridge drivers). Make them const to make this clear.
Linus Walleij [Fri, 11 Jan 2019 17:54:06 +0000 (18:54 +0100)]
drm/panel: Add a driver for the TPO TPG110
The TPO (Toppoly) TPG110 is a pretty generic display driver
similar in vein to the Ilitek 93xx devices. It is not a panel
per se but a driver used with several low-cost noname panels.
This is used on the Nomadik NHK15 combined with a OSD
OSD057VA01CT display for WVGA 800x480.
The driver is pretty minimalistic right now but can be
extended to handle non-default polarities, gamma correction
etc.
The driver is based on the baked-in code in
drivers/video/fbdev/amba-clcd-nomadik.c which will be
decomissioned once this us upstream.
drm: Auto-set allow_fb_modifiers when given modifiers at plane init
When drivers pass non-empty lists of modifiers for initializing their
planes, we can infer that they allow framebuffer modifiers and set the
driver's allow_fb_modifiers mode config element.
In case the allow_fb_modifiers element was not set (some drivers tend
to set them after registering planes), the modifiers will still be
registered but won't be available to userspace unless the flag is set
later. However in that case, the IN_FORMATS blob won't be created.
In order to avoid this case and generally reduce the trouble associated
with the flag, always set allow_fb_modifiers when a non-empty list of
format modifiers is passed at plane init.
drm/vc4: Limit SAND tiling support to semiplanar YUV420 formats
Despite what the HVS documentation indicates, the VC4 does not actually
support SAND tiling modes for any RGB format and only semiplanar YUV420
formats (NV12/NV21) can be used in these tiling modes.
The driver currently claims to support RGB formats for the associated
modifiers, so remove them from the supported list in the
format_mod_supported helper for RGB formats.
Remove further checks that are no longer necessary along the way, since
semi-planar YUV420 formats support every SAND tiling mode.
Daniel Vetter [Mon, 17 Dec 2018 19:42:58 +0000 (20:42 +0100)]
drm/nouveau: Stop using drm_crtc_force_disable
The correct way for legacy drivers to update properties that need to
do a full modeset, is to do a full modeset.
Note that we don't need to call the drm_mode_config_internal helper
because we're not changing any of the refcounted paramters.
v2: Fixup error handling (Ville). Since the old code didn't bother
I decided to just delete it instead of adding even more code for just
error handling.
Daniel Vetter [Mon, 17 Dec 2018 19:42:57 +0000 (20:42 +0100)]
drm/ch7006: Stop using drm_crtc_force_disable
The correct way for legacy drivers to update properties that need to
do a full modeset, is to do a full modeset.
Note that we don't need to call the drm_mode_config_internal helper
because we're not changing any of the refcounted paramters.
v2: Fixup error handling (Ville). Since the old code didn't bother
I decided to just delete it instead of adding even more code for just
error handling.
Lyude Paul [Fri, 11 Jan 2019 00:53:43 +0000 (19:53 -0500)]
drm/nouveau: Use atomic VCPI helpers for MST
Currently, nouveau uses the yolo method of setting up MST displays: it
uses the old VCPI helpers (drm_dp_find_vcpi_slots()) for computing the
display configuration. These helpers don't take care to make sure they
take a reference to the mstb port that they're checking, and
additionally don't actually check whether or not the topology still has
enough bandwidth to provide the VCPI tokens required.
So, drop usage of the old helpers and move entirely over to the atomic
helpers.
Changes since v6:
* Cleanup atomic check logic and remove a bunch of unneeded checks -
danvet
Changes since v5:
* Update nv50_msto_atomic_check() and nv50_mstc_atomic_check() to the
new requirements for drm_dp_atomic_find_vcpi_slots() and
drm_dp_atomic_release_vcpi_slots()
There has been a TODO waiting for quite a long time in
drm_dp_mst_topology.c:
/* We cannot rely on port->vcpi.num_slots to update
* topology_state->avail_slots as the port may not exist if the parent
* branch device was unplugged. This should be fixed by tracking
* per-port slot allocation in drm_dp_mst_topology_state instead of
* depending on the caller to tell us how many slots to release.
*/
That's not the only reason we should fix this: forcing the driver to
track the VCPI allocations throughout a state's atomic check is
error prone, because it means that extra care has to be taken with the
order that drm_dp_atomic_find_vcpi_slots() and
drm_dp_atomic_release_vcpi_slots() are called in in order to ensure
idempotency. Currently the only driver actually using these helpers,
i915, doesn't even do this correctly: multiple ->best_encoder() checks
with i915's current implementation would not be idempotent and would
over-allocate VCPI slots, something I learned trying to implement
fallback retraining in MST.
So: simplify this whole mess, and teach drm_dp_atomic_find_vcpi_slots()
and drm_dp_atomic_release_vcpi_slots() to track the VCPI allocations for
each port. This allows us to ensure idempotency without having to rely
on the driver as much. Additionally: the driver doesn't need to do any
kind of VCPI slot tracking anymore if it doesn't need it for it's own
internal state.
Additionally; this adds a new drm_dp_mst_atomic_check() helper which
must be used by atomic drivers to perform validity checks for the new
VCPI allocations incurred by a state.
Also: update the documentation and make it more obvious that these
/must/ be called by /all/ atomic drivers supporting MST.
Changes since v9:
* Add some missing changes that were requested by danvet that I forgot
about after I redid all of the kref stuff:
* Remove unnecessary state changes in intel_dp_mst_atomic_check
* Cleanup atomic check logic for VCPI allocations - all we need to check in
compute_config is whether or not this state disables a CRTC, then free
VCPI based off that
Changes since v8:
* Fix compile errors, whoops!
Changes since v7:
- Don't check for mixed stale/valid VCPI allocations, just rely on
connector registration to stop such erroneous modesets
Changes since v6:
- Keep a kref to all of the ports we have allocations on. This required
a good bit of changing to when we call drm_dp_find_vcpi_slots(),
mainly that we need to ensure that we only redo VCPI allocations on
actual mode or CRTC changes, not crtc_state->active changes.
Additionally, we no longer take the registration of the DRM connector
for each port into account because so long as we have a kref to the
port in the new or previous atomic state, the connector will stay
registered.
- Use the small changes to drm_dp_put_port() to add even more error
checking to make misusage of the helpers more obvious. I added this
after having to chase down various use-after-free conditions that
started popping up from the new helpers so no one else has to
troubleshoot that.
- Move some accidental DRM_DEBUG_KMS() calls to DRM_DEBUG_ATOMIC()
- Update documentation again, note that find/release() should both not be
called on the same port in a single atomic check phase (but multiple
calls to one or the other is OK)
Changes since v4:
- Don't skip the atomic checks for VCPI allocations if no new VCPI
allocations happen in a state. This makes the next change I'm about
to list here a lot easier to implement.
- Don't ignore VCPI allocations on destroyed ports, instead ensure that
when ports are destroyed and still have VCPI allocations in the
topology state, the only state changes allowed are releasing said
ports' VCPI. This prevents a state with a mix of VCPI allocations
from destroyed ports, and allocations from valid ports.
Changes since v3:
- Don't release VCPI allocations in the topology state immediately in
drm_dp_atomic_release_vcpi_slots(), instead mark them as 0 and skip
over them in drm_dp_mst_duplicate_state(). This makes it so
drm_dp_atomic_release_vcpi_slots() is still idempotent while also
throwing warnings if the driver messes up it's book keeping and tries
to release VCPI slots on a port that doesn't have any pre-existing
VCPI allocation - danvet
- Change mst_state/state in some debugging messages to "mst state"
Changes since v2:
- Use kmemdup() for duplicating MST state - danvet
- Move port validation out of duplicate state callback - danvet
- Handle looping through MST topology states in
drm_dp_mst_atomic_check() so the driver doesn't have to do it
- Fix documentation in drm_dp_atomic_find_vcpi_slots()
- Move the atomic check for each individual topology state into it's
own function, reduces indenting
- Don't consider "stale" MST ports when calculating the bandwidth
requirements. This is needed because originally we relied on the
state duplication functions to prune any stale ports from the new
state, which would prevent us from incorrectly considering their
bandwidth requirements alongside legitimate new payloads.
- Add function references in drm_dp_atomic_release_vcpi_slots() - danvet
- Annotate atomic VCPI and atomic check functions with __must_check
- danvet
Changes since v1:
- Don't use the now-removed ->atomic_check() for private objects hook,
just give drivers a function to call themselves
Lyude Paul [Fri, 11 Jan 2019 00:53:40 +0000 (19:53 -0500)]
drm/dp_mst: Add some atomic state iterator macros
Changes since v6:
- Move EXPORT_SYMBOL() for drm_dp_mst_topology_state_funcs to this
commit
- Document __drm_dp_mst_state_iter_get() and note that it shouldn't be
called directly
Lyude Paul [Fri, 11 Jan 2019 00:53:39 +0000 (19:53 -0500)]
drm/nouveau: Grab payload lock in nv50_msto_payload()
Going through the currently programmed payloads isn't safe without
holding mgr->payload_lock, so actually do that and warn if anyone tries
calling nv50_msto_payload() in the future without grabbing the right
locks.
Lyude Paul [Fri, 11 Jan 2019 00:53:38 +0000 (19:53 -0500)]
drm/nouveau: Stop unsetting mstc->port, use malloc refs
Same as we did for i915, but for nouveau this time. Additionally, we
grab a malloc reference to the port that lasts for the entire lifetime
of nv50_mstc, which gives us the guarantee that mstc->port will always
point to valid memory for as long as the mstc stays around.
Lyude Paul [Fri, 11 Jan 2019 00:53:37 +0000 (19:53 -0500)]
drm/nouveau: Keep malloc references to MST ports
Now that we finally have a sane way to keep port allocations around, use
it to fix the potential unchecked ->port accesses that nouveau makes by
making sure we keep the mst port allocated for as long as it's
drm_connector is accessible.
Additionally, now that we've guaranteed that mstc->port is allocated for
as long as we keep mstc around we can remove the connector registration
checks for codepaths which release payloads, allowing us to release
payloads on active topologies properly. These registration checks were
only required before in order to avoid situations where mstc->port could
technically be pointing at freed memory.
Lyude Paul [Fri, 11 Jan 2019 00:53:36 +0000 (19:53 -0500)]
drm/nouveau: Remove unnecessary VCPI checks in nv50_msto_cleanup()
There is no need to look at the port's VCPI allocation before calling
drm_dp_mst_deallocate_vcpi(), as we already have msto->disabled to let
us avoid cleaning up an msto more then once. The DP MST core will never
call drm_dp_mst_deallocate_vcpi() on it's own, which is presumably what
these checks are meant to protect against.
More importantly though, we're about to stop clearing mstc->port in the
next commit, which means if we could potentially hit a use-after-free
error if we tried to check mstc->port->vcpi here. So to make life easier
for anyone who bisects this code in the future, use msto->disabled
instead to check whether or not we need to deallocate VCPI instead.
Lyude Paul [Fri, 11 Jan 2019 00:53:35 +0000 (19:53 -0500)]
drm/nouveau: Remove bogus cleanup in nv50_mstm_add_connector()
Trying to destroy the connector using mstc->connector.funcs->destroy()
if connector initialization fails is wrong: there is no possible
codepath in nv50_mstc_new where nv50_mstm_add_connector() would return
<0 and mstc would be non-NULL.
Lyude Paul [Fri, 11 Jan 2019 00:53:34 +0000 (19:53 -0500)]
drm/amdgpu/display: Keep malloc ref to MST port
Just like i915 and nouveau, it's a good idea for us to hold a malloc
reference to the port here so that we never pass a freed pointer to any
of the DP MST helper functions.
Also, we stop unsetting aconnector->port in
dm_dp_destroy_mst_connector(). There's literally no point to that
assignment that I can see anyway.
Lyude Paul [Fri, 11 Jan 2019 00:53:33 +0000 (19:53 -0500)]
drm/i915: Keep malloc references to MST ports
So that the ports stay around until we've destroyed the connectors, in
order to ensure that we don't pass an invalid pointer to any MST helpers
once we introduce the new MST VCPI helpers.
Changes since v1:
* Move drm_dp_mst_get_port_malloc() to where we assign
intel_connector->port - danvet
Lyude Paul [Fri, 11 Jan 2019 00:53:32 +0000 (19:53 -0500)]
drm/dp_mst: Fix payload deallocation on hotplugs using malloc refs
Up until now, freeing payloads on remote MST hubs that just had ports
removed has almost never worked because we've been relying on port
validation in order to stop us from accessing ports that have already
been freed from memory, but ports which need their payloads released due
to being removed will never be a valid part of the topology after
they've been removed.
Since we've introduced malloc refs, we can replace all of the validation
logic in payload helpers which are used for deallocation with some
well-placed malloc krefs. This ensures that regardless of whether or not
the ports are still valid and in the topology, any port which has an
allocated payload will remain allocated in memory until it's payloads
have been removed - finally allowing us to actually release said
payloads correctly.
Lyude Paul [Fri, 11 Jan 2019 00:53:31 +0000 (19:53 -0500)]
drm/dp_mst: Stop releasing VCPI when removing ports from topology
This has never actually worked, and isn't needed anyway: the driver's
always going to try to deallocate VCPI when it tears down the display
that the VCPI belongs to.
Lyude Paul [Fri, 11 Jan 2019 00:53:30 +0000 (19:53 -0500)]
drm/dp_mst: Restart last_connected_port_and_mstb() if topology ref fails
While this isn't a complete fix, this will improve the reliability of
drm_dp_get_last_connected_port_and_mstb() pretty significantly during
hotplug events, since there's a chance that the in-memory topology tree
may not be fully updated when drm_dp_get_last_connected_port_and_mstb()
is called and thus might end up causing our search to fail on an mstb
whose topology refcount has reached 0, but has not yet been removed from
it's parent.
Ideally, we should further fix this problem by ensuring that we deal
with the potential for racing with a hotplug event, which would look
like this:
* drm_dp_payload_send_msg() retrieves the last living relative of mstb
with drm_dp_get_last_connected_port_and_mstb()
* drm_dp_payload_send_msg() starts building payload message
At the same time, mstb gets unplugged from the topology and is no
longer the actual last living relative of the original mstb
* drm_dp_payload_send_msg() tries sending the payload message, hub times
out
* Hub timed out, we give up and run away-resulting in the payload being
leaked
This could be fixed by restarting the
drm_dp_get_last_connected_port_and_mstb() search whenever we get a
timeout, sending the payload to the new mstb, then repeating until
either the entire topology is removed from the system or
drm_dp_get_last_connected_port_and_mstb() fails. But since the above
race condition is not terribly likely, we'll address that in a later
patch series once we've improved the recovery handling for VCPI
allocations in the rest of the DP MST helpers.
Changes since v1:
* Convert kerneldoc for drm_dp_get_last_connected_port_and_mstb to
normal comment - danvet
Lyude Paul [Fri, 11 Jan 2019 00:53:29 +0000 (19:53 -0500)]
drm/dp_mst: Introduce new refcounting scheme for mstbs and ports
The current way of handling refcounting in the DP MST helpers is really
confusing and probably just plain wrong because it's been hacked up many
times over the years without anyone actually going over the code and
seeing if things could be simplified.
To the best of my understanding, the current scheme works like this:
drm_dp_mst_port and drm_dp_mst_branch both have a single refcount. When
this refcount hits 0 for either of the two, they're removed from the
topology state, but not immediately freed. Both ports and branch devices
will reinitialize their kref once it's hit 0 before actually destroying
themselves. The intended purpose behind this is so that we can avoid
problems like not being able to free a remote payload that might still
be active, due to us having removed all of the port/branch device
structures in memory, as per:
commit 91a25e463130 ("drm/dp/mst: deallocate payload on port destruction")
Which may have worked, but then it caused use-after-free errors. Being
new to MST at the time, I tried fixing it;
commit 263efde31f97 ("drm/dp/mst: Get validated port ref in drm_dp_update_payload_part1()")
But, that was broken: both drm_dp_mst_port and drm_dp_mst_branch structs
are validated in almost every DP MST helper function. Simply put, this
means we go through the topology and try to see if the given
drm_dp_mst_branch or drm_dp_mst_port is still attached to something
before trying to use it in order to avoid dereferencing freed memory
(something that has happened a LOT in the past with this library).
Because of this it doesn't actually matter whether or not we keep keep
the ports and branches around in memory as that's not enough, because
any function that validates the branches and ports passed to it will
still reject them anyway since they're no longer in the topology
structure. So, use-after-free errors were fixed but payload deallocation
was completely broken.
Two years later, AMD informed me about this issue and I attempted to
come up with a temporary fix, pending a long-overdue cleanup of this
library:
commit c54c7374ff44 ("drm/dp_mst: Skip validating ports during destruction, just ref")
But then that introduced use-after-free errors, so I quickly reverted
it:
commit 9765635b3075 ("Revert "drm/dp_mst: Skip validating ports during destruction, just ref"")
And in the process, learned that there is just no simple fix for this:
the design is just broken. Unfortunately, the usage of these helpers are
quite broken as well. Some drivers like i915 have been smart enough to
avoid accessing any kind of information from MST port structures, but
others like nouveau have assumed, understandably so, that
drm_dp_mst_port structures are normal and can just be accessed at any
time without worrying about use-after-free errors.
After a lot of discussion, me and Daniel Vetter came up with a better
idea to replace all of this.
To summarize, since this is documented far more indepth in the
documentation this patch introduces, we make it so that drm_dp_mst_port
and drm_dp_mst_branch structures have two different classes of
refcounts: topology_kref, and malloc_kref. topology_kref corresponds to
the lifetime of the given drm_dp_mst_port or drm_dp_mst_branch in it's
given topology. Once it hits zero, any associated connectors are removed
and the branch or port can no longer be validated. malloc_kref
corresponds to the lifetime of the memory allocation for the actual
structure, and will always be non-zero so long as the topology_kref is
non-zero. This gives us a way to allow callers to hold onto port and
branch device structures past their topology lifetime, and dramatically
simplifies the lifetimes of both structures. This also finally fixes the
port deallocation problem, properly.
Additionally: since this now means that we can keep ports and branch
devices allocated in memory for however long we need, we no longer need
a significant amount of the port validation that we currently do.
Additionally, there is one last scenario that this fixes, which couldn't
have been fixed properly beforehand:
- CPU1 unrefs port from topology (refcount 1->0)
- CPU2 refs port in topology(refcount 0->1)
Since we now can guarantee memory safety for ports and branches
as-needed, we also can make our main reference counting functions fix
this problem by using kref_get_unless_zero() internally so that topology
refcounts can only ever reach 0 once.
Changes since v4:
* Change the kernel-figure summary for dp-mst/topology-figure-1.dot a
bit - danvet
* Remove figure numbers - danvet
Changes since v3:
* Remove rebase detritus - danvet
* Split out purely style changes into separate patches - hwentlan
Changes since v1:
* Remove forward declarations - danvet
* Move "Branch device and port refcounting" section from documentation
into kernel-doc comments - danvet
* Export internal topology lifetime functions into their own section in
the kernel-docs - danvet
* s/@/&/g for struct references in kernel-docs - danvet
* Drop the "when they are no longer being used" bits from the kernel
docs - danvet
* Modify diagrams to show how the DRM driver interacts with the topology
and payloads - danvet
* Make suggested documentation changes for
drm_dp_mst_topology_get_mstb() and drm_dp_mst_topology_get_port() -
danvet
* Better explain the relationship between malloc refs and topology krefs
in the documentation for drm_dp_mst_topology_get_port() and
drm_dp_mst_topology_get_mstb() - danvet
* Fix "See also" in drm_dp_mst_topology_get_mstb() - danvet
* Rename drm_dp_mst_topology_get_(port|mstb)() ->
drm_dp_mst_topology_try_get_(port|mstb)() and
drm_dp_mst_topology_ref_(port|mstb)() ->
drm_dp_mst_topology_get_(port|mstb)() - danvet
* s/should/must in docs - danvet
* WARN_ON(refcount == 0) in topology_get_(mstb|port) - danvet
* Move kdocs for mstb/port structs inline - danvet
* Split drm_dp_get_last_connected_port_and_mstb() changes into their own
commit - danvet
Ezequiel Garcia [Wed, 9 Jan 2019 18:56:38 +0000 (15:56 -0300)]
drm/rockchip: Separate RK3288 from RK3368 win01 registers
This commit splits the registers for RK3288 from those
for RK3328, RK3368 and RK3399. It seems RK3288 does not
support plane x-y-mirroring, and so in order to support this
for the other SoCs, we need to have separate set of registers
for win0 and win1.
Ezequiel Garcia [Wed, 9 Jan 2019 18:56:37 +0000 (15:56 -0300)]
drm/rockchip: Fix typo in VOP macros argument
Fix a small typo in the macros VOP argument. The macro argument
is currently wrongly named "x", and then never used. The code
built fine almost by accident, as the macros are always used
in a context where a proper "vop" symbol exists.
This fix is almost cosmetic, as the resulting code shouldn't change.
Currently, YUV hardware overlays are converted to RGB using
a color space conversion different than BT.601.
The result is that colors of e.g. NV12 buffers don't match
colors of YUV hardware overlays.
In order to fix this, enable YUV2YUV and set appropriate coefficients
for formats such as NV12 to be displayed correctly.
This commit was tested using modetest, gstreamer and chromeos (hardware
accelerated video playback). Before the commit, tests rendering
with NV12 format resulted in colors not displayed correctly.
Test examples (Tested on RK3399 and RK3288 boards
connected to HDMI monitor):
Linus Walleij [Thu, 10 Jan 2019 11:40:49 +0000 (12:40 +0100)]
drm/fb-helper: Scale back depth to supported maximum
The following happened when migrating an old fbdev driver to DRM:
The Integrator/CP PL111 supports 16BPP but only ARGB1555/ABGR1555
or XRGB1555/XBGR1555 i.e. the maximum depth is 15.
This makes the initialization of the framebuffer fail since
the code in drm_fb_helper_single_fb_probe() assigns the same value
to sizes.surface_bpp and sizes.surface_depth. I.e. it simply assumes
a 1-to-1 mapping between BPP and depth, which is true in most cases
but not for this hardware that only support odd formats.
To support the odd case of a driver supporting 16BPP with only 15
bits of depth, this patch will make the code loop over the formats
supported on the primary plane on each CRTC managed by the FB
helper and cap the depth to the maximum supported on any primary
plane.
On the PL110 Integrator, this makes drm_mode_legacy_fb_format()
select DRM_FORMAT_XRGB1555 which is acceptable for this driver, and
thus we get framebuffer, penguin and console on the Integrator/CP.
Ville Syrjälä [Tue, 8 Jan 2019 17:28:27 +0000 (19:28 +0200)]
drm/radeon: Use drm_hdmi_avi_infoframe_quant_range()
Fill out the AVI infoframe quantization range bits using
drm_hdmi_avi_infoframe_quant_range() instead of hand rolling it.
This changes the behaviour slightly as
drm_hdmi_avi_infoframe_quant_range() will set a non-zero Q bit
even when QS==0 iff the Q bit matched the default quantization
range for the given mode. This matches the recommendation in
HDMI 2.0 and is allowed even before that.
Ville Syrjälä [Tue, 8 Jan 2019 17:28:26 +0000 (19:28 +0200)]
drm/i915: Use drm_hdmi_avi_infoframe_quant_range() for SDVO HDMI as well
Fill out the AVI infoframe quantization range bits using
drm_hdmi_avi_infoframe_quant_range() for SDVO HDMI encoder as well.
This changes the behaviour slightly as
drm_hdmi_avi_infoframe_quant_range() will set a non-zero Q bit
even when QS==0 iff the Q bit matched the default quantization
range for the given mode. This matches the recommendation in
HDMI 2.0 and is allowed even before that.
Ville Syrjälä [Tue, 8 Jan 2019 17:28:25 +0000 (19:28 +0200)]
drm/edid: Pass connector to AVI infoframe functions
Make life easier for drivers by simply passing the connector
to drm_hdmi_avi_infoframe_from_display_mode() and
drm_hdmi_avi_infoframe_quant_range(). That way drivers don't
need to worry about is_hdmi2_sink mess.
v2: Make is_hdmi2_sink() return true for sil-sii8620
Adapt to omap/vc4 changes
Chris Wilson [Wed, 9 Jan 2019 16:42:04 +0000 (16:42 +0000)]
drm/i915: Removing polling for struct_mutex from vmap shrinker
The wait-for-idle used from within the shrinker_lock_uninterruptible
depends on the struct_mutex locking state being known and declared to
i915_request_wait(). As it is conceivable that we reach the vmap
notifier from underneath struct_mutex (and so keep on relying on the
mutex_trylock_recursive), we should not blindly call i915_request_wait.
In the process we can remove the dubious polling to acquire
struct_mutex, and simply act, or not, on a successful trylock.
Chris Wilson [Wed, 9 Jan 2019 16:42:03 +0000 (16:42 +0000)]
drm/i915: Use mutex_lock_killable() from inside the shrinker
If the current process is being killed (it was interrupted with SIGKILL
or equivalent), it will not make any progress in page allocation and we
can abort performing the shrinking on its behalf. So we can use
mutex_lock_killable() instead (although this path should only be
reachable from kswapd currently).
Tvrtko pointed out that it should also be reachable from debugfs, which
he would prefer retain its interruptiblity. As a compromise, killable is a
step in the right direction!
Chris Wilson [Thu, 10 Jan 2019 11:15:22 +0000 (11:15 +0000)]
drm/i915: Guard error capture against unpinned vma
If we find an incompletely setup vma inside the request/engine at the
time of a hang, it may not have vma->pages initialised, so skip
capturing the object before we iterate over NULL.
Spotted by Matthew in preparation for using unpinned vma to track engine
state.
Daniel Vetter [Thu, 10 Jan 2019 10:30:45 +0000 (11:30 +0100)]
drm/crtc-helpers: WARN when used with atomic drivers
Motivated by an oversight of mine when looking at the atomic bochs
conversion. For consistency also switch over to the same style as used
elsewhere (e.g. in drm_mode_set_config_internal).
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