Several DRM/KMS atomic commits can run in parallel if they affect
different CRTC. These commits share the global HVS state, so we have
some code to make sure we run commits in sequence. This synchronization
code is one of the first thing that runs in vc4_atomic_commit_tail().
Another constraints we have is that we need to make sure the HVS clock
gets a boost during the commit. That code relies on clk_set_min_rate and
will remove the old minimum and set a new one. We also need another,
temporary, minimum for the duration of the commit.
The algorithm is thus to set a temporary minimum, drop the previous
one, do the commit, and finally set the minimum for the current mode.
However, the part that sets the temporary minimum and drops the older
one runs before the commit synchronization code.
Thus, under the proper conditions, we can end up mixing up the minimums
and ending up with the wrong one for our current step.
To avoid it, let's move the clock setup in the protected section.
Fixes: d7d96c00e5 ("drm/vc4: hvs: Boost the core clock during modeset")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
[danvet: re-apply this from 0c980a006d ("drm/vc4: kms: Wait for the
commit before increasing our clock rate") because I lost that part in
my merge resolution in 99b03ca651 ("Merge v5.16-rc5 into drm-next")]
Fixes: 99b03ca651 ("Merge v5.16-rc5 into drm-next")
Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://lore.kernel.org/r/20211117094527.146275-2-maxime@cerno.tech
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Merge v5.16-rc5 into drm-next
Thomas Zimmermann requested a fixes backmerge, specifically also for
96c5f82ef0 ("drm/vc4: fix error code in vc4_create_object()")
Just a bunch of adjacent changes conflicts, even the big pile of them
in vc4.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Our current code is supposed to serialise the commits by waiting for all
the drm_crtc_commits associated to the previous HVS state.
However, assuming we have two CRTCs running and being configured and we
configure each one alternately, we end up in a situation where we're
not waiting at all.
Indeed, starting with a state (state 0) where both CRTCs are running,
and doing a commit (state 1) on the first CRTC (CRTC 0), we'll associate
its commit to its assigned FIFO in vc4_hvs_state.
If we get a new commit (state 2), this time affecting the second CRTC
(CRTC 1), the DRM core will allow both commits to execute in parallel
(assuming they don't have any share resources).
Our code in vc4_atomic_commit_tail is supposed to make sure we only get
one commit at a time and serialised by order of submission. It does so
by using for_each_old_crtc_in_state, making sure that the CRTC has a
FIFO assigned, is used, and has a commit pending. If it does, then we'll
wait for the commit before going forward.
During the transition from state 0 to state 1, as our old CRTC state we
get the CRTC 0 state 0, its commit, we wait for it, everything works fine.
During the transition from state 1 to state 2 though, the use of
for_each_old_crtc_in_state is wrong. Indeed, while the code assumes it's
returning the state of the CRTC in the old state (so CRTC 0 state 1), it
actually returns the old state of the CRTC affected by the current
commit, so CRTC 0 state 0 since it wasn't part of state 1.
Due to this, if we alternate between the configuration of CRTC 0 and
CRTC 1, we never actually wait for anything since we should be waiting
on the other every time, but it never is affected by the previous
commit.
Change the logic to, at every commit, look at every FIFO in the previous
HVS state, and if it's in use and has a commit associated to it, wait
for that commit.
Fixes: 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-7-maxime@cerno.tech
Our HVS global state, when duplicated, will also copy the pointer to the
drm_crtc_commit (and increase the reference count) for each FIFO if the
pointer is not NULL.
However, our atomic_setup function will overwrite that pointer without
putting the reference back leading to a memory leak.
Since the commit is only relevant during the atomic commit process, it
doesn't make sense to duplicate the reference to the commit anyway.
Let's remove it.
Fixes: 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-6-maxime@cerno.tech
Commit 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a
commit") introduced a wait on the previous commit done on a given HVS
FIFO.
However, we never cleared that pointer once done. Since
drm_crtc_commit_put can free the drm_crtc_commit structure directly if
we were the last user, this means that it can lead to a use-after free
if we were to duplicate the state, and that stale pointer would even be
copied to the new state.
Set the pointer to NULL once we're done with the wait so that we don't
carry over a pointer to a free'd structure.
Fixes: 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-5-maxime@cerno.tech
Commit 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a
commit") introduced a global state for the HVS, with each FIFO storing
the current CRTC commit so that we can properly synchronize commits.
However, the refcounting was off and we thus ended up leaking the
drm_crtc_commit structure every commit. Add a drm_crtc_commit_put to
prevent the leakage.
Fixes: 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-4-maxime@cerno.tech
The HVS global state functions return an error pointer, but in most
cases we check if it's NULL, possibly resulting in an invalid pointer
dereference.
Fixes: 9ec03d7f1e ("drm/vc4: kms: Wait on previous FIFO users before a commit")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-3-maxime@cerno.tech
Several DRM/KMS atomic commits can run in parallel if they affect
different CRTC. These commits share the global HVS state, so we have
some code to make sure we run commits in sequence. This synchronization
code is one of the first thing that runs in vc4_atomic_commit_tail().
Another constraints we have is that we need to make sure the HVS clock
gets a boost during the commit. That code relies on clk_set_min_rate and
will remove the old minimum and set a new one. We also need another,
temporary, minimum for the duration of the commit.
The algorithm is thus to set a temporary minimum, drop the previous
one, do the commit, and finally set the minimum for the current mode.
However, the part that sets the temporary minimum and drops the older
one runs before the commit synchronization code.
Thus, under the proper conditions, we can end up mixing up the minimums
and ending up with the wrong one for our current step.
To avoid it, let's move the clock setup in the protected section.
Fixes: d7d96c00e5 ("drm/vc4: hvs: Boost the core clock during modeset")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Link: https://lore.kernel.org/r/20211117094527.146275-2-maxime@cerno.tech
Accessing the crtc->state pointer from outside the modesetting context
is not allowed. We thus need to copy whatever we need from the KMS state
to our structure in order to access it.
In VC4, a number of users of that pointers have crept in over the years,
the first one being whether or not the downstream controller of the
pixelvalve is our writeback controller.
Fortunately for us, Since commit 39fcb28083 ("drm/vc4: txp: Turn the
TXP into a CRTC of its own") this is no longer something that can change
from one commit to the other and is hardcoded.
Let's set this flag in struct vc4_crtc if we happen to be the TXP, and
drop the flag from our private state structure.
Link: https://lore.kernel.org/all/YWgteNaNeaS9uWDe@phenom.ffwll.local/
Link: https://lore.kernel.org/r/20211025141113.702757-2-maxime@cerno.tech
Fixes: 008095e065 ("drm/vc4: Add support for the transposer block")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Depending on a given HVS output (HVS to PixelValves) and input (planes
attached to a channel) load, the HVS needs for the core clock to be
raised above its boot time default.
Failing to do so will result in a vblank timeout and a stalled display
pipeline.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20211025152903.1088803-11-maxime@cerno.tech
The load tracker was initially designed to report and warn about a load
too high for the HVS. To do so, it computes for each plane the impact
it's going to have on the HVS, and will warn (if it's enabled) if we go
over what the hardware can process.
While the limits being used are a bit irrelevant to the BCM2711, the
algorithm to compute the HVS load will be one component used in order to
compute the core clock rate on the BCM2711.
Let's remove the hooks to prevent the load tracker to do its
computation, but since we don't have the same limits, don't check them
against them, and prevent the debugfs file to enable it from being
created.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20211025152903.1088803-8-maxime@cerno.tech
UAPI Changes:
Cross-subsystem Changes:
- udmabuf: Add support for mapping hugepages
- Add dma-buf stats to sysfs.
- Assorted fixes to fbdev/omap2.
- dma-buf: Document DMA_BUF_IOCTL_SYNC
- Improve dma-buf non-dynamic exporter expectations better.
- Add module parameters for dma-buf size and list limit.
- Add HDMI codec support to vc4, to replace vc4's own codec.
- Document dma-buf implicit fencing rules.
- dma_resv_test_signaled test_all handling.
Core Changes:
- Extract i915's eDP backlight code into DRM helpers.
- Assorted docbook updates.
- Rework drm_dp_aux documentation.
- Add support for the DP aux bus.
- Shrink dma-fence-chain slightly.
- Add alloc/free helpers for dma-fence-chain.
- Assorted fixes to TTM., drm/of, bridge
- drm_gem_plane_helper_prepare/cleanup_fb is now the default for gem drivers.
- Small fix for scheduler completion.
- Remove use of drm_device.irq_enabled.
- Print the driver name to dmesg when registering framebuffer.
- Export drm/gem's shadow plane handling, and use it in vkms.
- Assorted small fixes.
Driver Changes:
- Add eDP backlight to nouveau.
- Assorted fixes and cleanups to nouveau, panfrost, vmwgfx, anx7625,
amdgpu, gma500, radeon, mgag200, vgem, vc4, vkms, omapdrm.
- Add support for Samsung DB7430, Samsung ATNA33XC20, EDT ETMV570G2DHU,
EDT ETM0350G0DH6, Innolux EJ030NA panels.
- Fix some simple pannels missing bus_format and connector types.
- Add mks-guest-stats instrumentation support to vmwgfx.
- Merge i915-ttm topic branch.
- Make s6e63m0 panel use Mipi-DBI helpers.
- Add detect() supoprt for AST.
- Use interrupts for hotplug on vc4.
- vmwgfx is now moved to drm-misc-next, as sroland is no longer a maintainer for now.
- vmwgfx now uses copies of vmware's internal device headers.
- Slowly convert ti-sn65dsi83 over to atomic.
- Rework amdgpu dma-resv handling.
- Fix virtio fencing for planes.
- Ensure amdgpu can always evict to SYSTEM.
- Many drivers fixed for implicit fencing rules.
- Set default prepare/cleanup fb for tiny, vram and simple helpers too.
- Rework panfrost gpu reset and related serialization.
- Update VKMS todo list.
- Make bochs a tiny gpu driver, and use vram helper.
- Use linux irq interfaces instead of drm_irq in some drivers.
- Add support for Raspberry Pi Pico to GUD.
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Merge tag 'drm-misc-next-2021-07-16' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
drm-misc-next for v5.15:
UAPI Changes:
Cross-subsystem Changes:
- udmabuf: Add support for mapping hugepages
- Add dma-buf stats to sysfs.
- Assorted fixes to fbdev/omap2.
- dma-buf: Document DMA_BUF_IOCTL_SYNC
- Improve dma-buf non-dynamic exporter expectations better.
- Add module parameters for dma-buf size and list limit.
- Add HDMI codec support to vc4, to replace vc4's own codec.
- Document dma-buf implicit fencing rules.
- dma_resv_test_signaled test_all handling.
Core Changes:
- Extract i915's eDP backlight code into DRM helpers.
- Assorted docbook updates.
- Rework drm_dp_aux documentation.
- Add support for the DP aux bus.
- Shrink dma-fence-chain slightly.
- Add alloc/free helpers for dma-fence-chain.
- Assorted fixes to TTM., drm/of, bridge
- drm_gem_plane_helper_prepare/cleanup_fb is now the default for gem drivers.
- Small fix for scheduler completion.
- Remove use of drm_device.irq_enabled.
- Print the driver name to dmesg when registering framebuffer.
- Export drm/gem's shadow plane handling, and use it in vkms.
- Assorted small fixes.
Driver Changes:
- Add eDP backlight to nouveau.
- Assorted fixes and cleanups to nouveau, panfrost, vmwgfx, anx7625,
amdgpu, gma500, radeon, mgag200, vgem, vc4, vkms, omapdrm.
- Add support for Samsung DB7430, Samsung ATNA33XC20, EDT ETMV570G2DHU,
EDT ETM0350G0DH6, Innolux EJ030NA panels.
- Fix some simple pannels missing bus_format and connector types.
- Add mks-guest-stats instrumentation support to vmwgfx.
- Merge i915-ttm topic branch.
- Make s6e63m0 panel use Mipi-DBI helpers.
- Add detect() supoprt for AST.
- Use interrupts for hotplug on vc4.
- vmwgfx is now moved to drm-misc-next, as sroland is no longer a maintainer for now.
- vmwgfx now uses copies of vmware's internal device headers.
- Slowly convert ti-sn65dsi83 over to atomic.
- Rework amdgpu dma-resv handling.
- Fix virtio fencing for planes.
- Ensure amdgpu can always evict to SYSTEM.
- Many drivers fixed for implicit fencing rules.
- Set default prepare/cleanup fb for tiny, vram and simple helpers too.
- Rework panfrost gpu reset and related serialization.
- Update VKMS todo list.
- Make bochs a tiny gpu driver, and use vram helper.
- Use linux irq interfaces instead of drm_irq in some drivers.
- Add support for Raspberry Pi Pico to GUD.
Signed-off-by: Dave Airlie <airlied@redhat.com>
# gpg: Signature made Fri 16 Jul 2021 21:06:04 AEST
# gpg: using RSA key B97BD6A80CAC4981091AE547FE558C72A67013C3
# gpg: Good signature from "Maarten Lankhorst <maarten.lankhorst@linux.intel.com>" [expired]
# gpg: aka "Maarten Lankhorst <maarten@debian.org>" [expired]
# gpg: aka "Maarten Lankhorst <maarten.lankhorst@canonical.com>" [expired]
# gpg: Note: This key has expired!
# Primary key fingerprint: B97B D6A8 0CAC 4981 091A E547 FE55 8C72 A670 13C3
From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/444811c3-cbec-e9d5-9a6b-9632eda7962a@linux.intel.com
The field drm_device.irq_enabled is only used by legacy drivers
with userspace modesetting. Don't set it in vc4.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210625082222.3845-24-tzimmermann@suse.de
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Backmerge tag 'v5.13-rc7' into drm-next
Backmerge Linux 5.13-rc7 to make some pulls from later bases apply,
and to bake in the conflicts so far.
In vc4_atomic_commit_tail() we iterate of the set of old CRTCs, and
attempt to wait on any channels which are still in use. When we iterate
over the CRTCs, we have:
* `i` - the index of the CRTC
* `channel` - the channel a CRTC is using
When we check the channel state, we consult:
old_hvs_state->fifo_state[channel].in_use
... but when we wait for the channel, we erroneously wait on:
old_hvs_state->fifo_state[i].pending_commit
... rather than:
old_hvs_state->fifo_state[channel].pending_commit
... and this bogus access has been observed to result in boot-time hangs
on some arm64 configurations, and can be detected using KASAN. FIx this
by using the correct index.
I've tested this on a Raspberry Pi 3 model B v1.2 with KASAN.
Trimmed KASAN splat:
| ==================================================================
| BUG: KASAN: slab-out-of-bounds in vc4_atomic_commit_tail+0x1cc/0x910
| Read of size 8 at addr ffff000007360440 by task kworker/u8:0/7
| CPU: 2 PID: 7 Comm: kworker/u8:0 Not tainted 5.13.0-rc3-00009-g694c523e7267 #3
|
| Hardware name: Raspberry Pi 3 Model B (DT)
| Workqueue: events_unbound deferred_probe_work_func
| Call trace:
| dump_backtrace+0x0/0x2b4
| show_stack+0x1c/0x30
| dump_stack+0xfc/0x168
| print_address_description.constprop.0+0x2c/0x2c0
| kasan_report+0x1dc/0x240
| __asan_load8+0x98/0xd4
| vc4_atomic_commit_tail+0x1cc/0x910
| commit_tail+0x100/0x210
| ...
|
| Allocated by task 7:
| kasan_save_stack+0x2c/0x60
| __kasan_kmalloc+0x90/0xb4
| vc4_hvs_channels_duplicate_state+0x60/0x1a0
| drm_atomic_get_private_obj_state+0x144/0x230
| vc4_atomic_check+0x40/0x73c
| drm_atomic_check_only+0x998/0xe60
| drm_atomic_commit+0x34/0x94
| drm_client_modeset_commit_atomic+0x2f4/0x3a0
| drm_client_modeset_commit_locked+0x8c/0x230
| drm_client_modeset_commit+0x38/0x60
| drm_fb_helper_set_par+0x104/0x17c
| fbcon_init+0x43c/0x970
| visual_init+0x14c/0x1e4
| ...
|
| The buggy address belongs to the object at ffff000007360400
| which belongs to the cache kmalloc-128 of size 128
| The buggy address is located 64 bytes inside of
| 128-byte region [ffff000007360400, ffff000007360480)
| The buggy address belongs to the page:
| page:(____ptrval____) refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7360
| flags: 0x3fffc0000000200(slab|node=0|zone=0|lastcpupid=0xffff)
| raw: 03fffc0000000200 dead000000000100 dead000000000122 ffff000004c02300
| raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
| page dumped because: kasan: bad access detected
|
| Memory state around the buggy address:
| ffff000007360300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ffff000007360380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
| >ffff000007360400: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
| ^
| ffff000007360480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
| ffff000007360500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ==================================================================
Link: https://lore.kernel.org/r/4d0c8318-bad8-2be7-e292-fc8f70c198de@samsung.com
Link: https://lore.kernel.org/linux-arm-kernel/20210607151740.moncryl5zv3ahq4s@gilmour
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Emma Anholt <emma@anholt.net>
Cc: Maxime Ripard <maxime@cerno.tech>
Cc: Will Deacon <will@kernel.org>
Cc: dri-devel@lists.freedesktop.org
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210608085513.2069-1-mark.rutland@arm.com
Since
commit 890880ddfd
Author: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Date: Fri Jan 4 09:56:10 2019 +0100
drm: Auto-set allow_fb_modifiers when given modifiers at plane init
this is done automatically as part of plane init, if drivers set the
modifier list correctly. Which is the case here.
Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210413094904.3736372-11-daniel.vetter@ffwll.ch
There's currently four users of the same logic to wait for a commit to
be flipped: three for the CRTCs, connectors and planes in
drm_atomic_helper_wait_for_dependencies, and one in vc4.
Let's consolidate this a bit to avoid any code duplication.
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210111084401.117152-1-maxime@cerno.tech
Now that the semaphore is gone, our atomic_commit implementation is
basically drm_atomic_helper_commit with a somewhat custom commit_tail,
the main difference being that we're using wait_for_flip_done instead of
wait_for_vblanks used in the drm_atomic_helper_commit_tail helper.
Let's switch to using drm_atomic_helper_commit.
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20201204151138.1739736-8-maxime@cerno.tech
The HVS state now has both unassigned_channels that reflects the
channels that are not used in the associated state, and the in_use
boolean for each channel that says whether or not a particular channel
is in use.
Both express pretty much the same thing, and we need the in_use variable
to properly track the commits, so let's get rid of unassigned_channels.
Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201204151138.1739736-6-maxime@cerno.tech
If we're having two subsequent, non-blocking, commits on two different
CRTCs that share no resources, there's no guarantee on the order of
execution of both commits.
However, the second one will consider the first one as the old state,
and will be in charge of freeing it once that second commit is done.
If the first commit happens after that second commit, it might access
some resources related to its state that has been freed, resulting in a
use-after-free bug.
The standard DRM objects are protected against this, but our HVS private
state isn't so let's make sure we wait for all the previous FIFO users
to finish their commit before going with our own.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201204151138.1739736-5-maxime@cerno.tech
The current HVS muxing code will consider the CRTCs in a given state to
setup their muxing in the HVS, and disable the other CRTCs muxes.
However, it's valid to only update a single CRTC with a state, and in this
situation we would mux out a CRTC that was enabled but left untouched by
the new state.
Fix this by setting a flag on the CRTC state when the muxing has been
changed, and only change the muxing configuration when that flag is there.
Fixes: 87ebcd42fb ("drm/vc4: crtc: Assign output to channel automatically")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120144245.398711-3-maxime@cerno.tech
If a CRTC is enabled but not active, and that we're then doing a page
flip on another CRTC, drm_atomic_get_crtc_state will bring the first
CRTC state into the global state, and will make us wait for its vblank
as well, even though that might never occur.
Instead of creating the list of the free channels each time atomic_check
is called, and calling drm_atomic_get_crtc_state to retrieve the
allocated channels, let's create a private state object in the main
atomic state, and use it to store the available channels.
Since vc4 has a semaphore (with a value of 1, so a lock) in its commit
implementation to serialize all the commits, even the nonblocking ones, we
are free from the use-after-free race if two subsequent commits are not ran
in their submission order.
Fixes: 87ebcd42fb ("drm/vc4: crtc: Assign output to channel automatically")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201120144245.398711-2-maxime@cerno.tech
We've had a number of muxing corner-cases with specific ways to reproduce
them, so let's document them to make sure they aren't lost and introduce
regressions later on.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105135656.383350-6-maxime@cerno.tech
The code that assigns HVS channels during atomic_check is starting to grow
a bit big, let's move it into a separate function.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105135656.383350-5-maxime@cerno.tech
The NUM_CHANNELS define has a pretty generic name and was right before the
function using it. Let's move to something that makes the hardware-specific
nature more obvious, and to a more appropriate place.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105135656.383350-4-maxime@cerno.tech
Even though it was pointed in the review by Daniel, and I thought to have
fixed it while applying the patches, but it turns out I forgot to commit
the fixes in the process. Properly fix it this time.
Fixes: dcda7c28bf ("drm/vc4: kms: Add functions to create the state objects")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105135656.383350-2-maxime@cerno.tech
In order to make the vc4_kms_load code and error path a bit easier to
read and extend, add functions to create state objects, and use managed
actions to cleanup if needed.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201029190104.2181730-6-maxime@cerno.tech
The HVS FIFOs are currently assigned each time we have an atomic_check
for all the enabled CRTCs.
However, if we are running multiple outputs in parallel and we happen to
disable the first (by index) CRTC, we end up changing the assigned FIFO
of the second CRTC without disabling and reenabling the pixelvalve which
ends up in a stall and eventually a VBLANK timeout.
In order to fix this, we can create a special value for our assigned
channel to mark it as disabled, and if our CRTC already had an assigned
channel in its previous state, we keep on using it.
Fixes: 87ebcd42fb ("drm/vc4: crtc: Assign output to channel automatically")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200923084032.218619-2-maxime@cerno.tech
The HVS has three FIFOs that can be assigned to a number of PixelValves
through a mux.
However, changing that FIFO requires that we disable and then enable the
pixelvalve, so we want to assign FIFOs to all the enabled CRTCs, and not
just the active ones.
Fixes: 87ebcd42fb ("drm/vc4: crtc: Assign output to channel automatically")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200918145918.101068-1-maxime@cerno.tech
The vc4 display engine has a first controller called the HVS that will
perform the composition of the planes. That HVS has 3 FIFOs and can
therefore compose planes for up to three outputs. The timings part is
generated through a component called the Pixel Valve, and the BCM2711 has 6
of them.
Thus, the HVS has some bits to control which FIFO gets output to which
Pixel Valve. The current code supports that muxing by looking at all the
CRTCs in a new DRM atomic state in atomic_check, and given the set of
constraints that we have, assigns FIFOs to CRTCs or reject the mode
entirely. The actual muxing will occur during atomic_commit.
However, that doesn't work if only a fraction of the CRTCs' state is
updated in that state, since it will ignore the CRTCs that are kept running
unmodified, and will thus unassign its associated FIFO, and later disable
it.
In order to make the code work as expected, let's pull the CRTC state of
all the enabled CRTC in our atomic_check so that we can operate on all the
running CRTCs, no matter whether they are affected by the new state or not.
Fixes: 87ebcd42fb ("drm/vc4: crtc: Assign output to channel automatically")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200917121623.42023-1-maxime@cerno.tech
The BCM2711 has a reworked display pipeline, and the load tracker needs
some adjustment to operate properly. Let's add a compatible for BCM2711
and disable the load tracker until properly supported.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/beac4f9ef0261bca731a0402c8354e9af740519c.1599120059.git-series.maxime@cerno.tech
The HVS found in the BCM2711 has 6 outputs and 3 FIFOs, with each output
being connected to a pixelvalve, and some muxing between the FIFOs and
outputs.
Any output cannot feed from any FIFO though, and they all have a bunch of
constraints.
In order to support this, let's store the possible FIFOs each output can be
assigned to in the vc4_crtc_data, and use that information at atomic_check
time to iterate over all the CRTCs enabled and assign them FIFOs.
The channel assigned is then set in the vc4_crtc_state so that the rest of
the driver can use it.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f9aba3814ef37156ff36f310118cdd3954dd3dc5.1599120059.git-series.maxime@cerno.tech
The vc4 atomic commit loop has an handrolled loop that is basically
identical to for_each_new_crtc_state, let's convert it to that helper.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/a712d2b70aaee20379cfc52c2141aa2f6e2a9d5b.1599120059.git-series.maxime@cerno.tech
In order to prevent timeouts and stalls in the pipeline, the core clock
needs to be maxed at 500MHz during a modeset on the BCM2711.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/37ed9e0124c5cce005ddc8dafe821d8b0da036ff.1599120059.git-series.maxime@cerno.tech
Spelling out _unlocked for each and every driver is a annoying.
Especially if we consider how many drivers, do not know (or need to)
about the horror stories involving struct_mutex.
Just drop the suffix. It makes the API cleaner.
Done via the following script:
__from=drm_gem_object_put_unlocked
__to=drm_gem_object_put
for __file in $(git grep --name-only $__from); do
sed -i "s/$__from/$__to/g" $__file;
done
Cc: Eric Anholt <eric@anholt.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200515095118.2743122-34-emil.l.velikov@gmail.com
Drop use of the deprecated header drmP.h.
Fix so vc4_drv.h is now self-contained, and fixed fall-out in remaining
files.
Divided include files in blocks.
Sorted include files within their blocks.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190716064220.18157-7-sam@ravnborg.org
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
One might want to use the VC4 display stack without using Mesa.
Similar to the debugfs fixes for not having all of the possible
display bits enabled, make sure you can't oops in vc4 if v3d isn't
enabled.
v2: Fix matching against other v3d variants (review by Paul), don't
forget to set irq_enabled so that the vblank uapi works
v3: Use -ENODEV instead of -EINVAL on Paul's suggestion.
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190401183559.3823-2-eric@anholt.net
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
In order to test whether the load tracker is working as expected, we
need the ability to compare the commit result with the underrun
indication. With the load tracker always enabled, commits that are
expected to trigger an underrun are always rejected, so userspace
cannot get the actual underrun indication from the hardware.
Add a debugfs entry to disable/enable the load tracker, so that a DRM
commit expected to trigger an underrun can go through with the load
tracker disabled. The underrun indication is then available to
userspace and can be checked against the commit result with the load
tracker enabled.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190220155124.25022-4-paul.kocialkowski@bootlin.com
The HVS block is supposed to fill the pixelvalve FIFOs fast enough to
meet the requested framerate. The problem is, the HVS and memory bus
bandwidths are limited, and if we don't take these limitations into
account we might end up with HVS underflow errors.
This patch is trying to model the per-plane HVS and memory bus bandwidth
consumption and take a decision at atomic_check() time whether the
estimated load will fit in the HVS and membus budget.
Note that we take an extra margin on the memory bus consumption to let
the system run smoothly when other blocks are doing heavy use of the
memory bus. Same goes for the HVS limit, except the margin is smaller in
this case, since the HVS is not used by external components.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190220155124.25022-3-paul.kocialkowski@bootlin.com
Add a debugfs entry and helper for reporting HVS underrun errors as
well as helpers for masking and unmasking the underrun interrupts.
Add an IRQ handler and initial IRQ configuration.
Rework related register definitions to take the channel number.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190220155124.25022-2-paul.kocialkowski@bootlin.com
Having the probe helper stuff (which pretty much everyone needs) in
the drm_crtc_helper.h file (which atomic drivers should never need) is
confusing. Split them out.
To make sure I actually achieved the goal here I went through all
drivers. And indeed, all atomic drivers are now free of
drm_crtc_helper.h includes.
v2: Make it compile. There was so much compile fail on arm drivers
that I figured I'll better not include any of the acks on v1.
v3: Massive rebase because i915 has lost a lot of drmP.h includes, but
not all: Through drm_crtc_helper.h > drm_modeset_helper.h -> drmP.h
there was still one, which this patch largely removes. Which means
rolling out lots more includes all over.
This will also conflict with ongoing drmP.h cleanup by others I
expect.
v3: Rebase on top of atomic bochs.
v4: Review from Laurent for bridge/rcar/omap/shmob/core bits:
- (re)move some of the added includes, use the better include files in
other places (all suggested from Laurent adopted unchanged).
- sort alphabetically
v5: Actually try to sort them, and while at it, sort all the ones I
touch.
v6: Rebase onto i915 changes.
v7: Rebase once more.
Acked-by: Harry Wentland <harry.wentland@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Acked-by: CK Hu <ck.hu@mediatek.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: virtualization@lists.linux-foundation.org
Cc: etnaviv@lists.freedesktop.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-amlogic@lists.infradead.org
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: nouveau@lists.freedesktop.org
Cc: spice-devel@lists.freedesktop.org
Cc: amd-gfx@lists.freedesktop.org
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-rockchip@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-tegra@vger.kernel.org
Cc: xen-devel@lists.xen.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190117210334.13234-1-daniel.vetter@ffwll.ch
drm_atomic_helper_setup_commit() auto-completes commit->flip_done when
state->legacy_cursor_update is true, but we know for sure that we want
a sync update when we call drm_atomic_helper_setup_commit() from
vc4_atomic_commit().
Explicitly set state->legacy_cursor_update to false to prevent this
auto-completion.
Fixes: 184d3cf4f7 ("drm/vc4: Use wait_for_flip_done() instead of wait_for_vblanks()")
Cc: <stable@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181115105852.9844-2-boris.brezillon@bootlin.com
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.
drm_fbdev_generic_setup() handles mode_config.num_connector being zero.
In that case it retries fbdev setup on the next .output_poll_changed.
Cc: Eric Anholt <eric@anholt.net>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20180908134648.2582-19-noralf@tronnes.org