kernel/linux.git/drivers/gpu/drm/vc4, branch v5.15.7

drm/vc4: kms: Fix previous HVS commit wait

2021-12-08T08:04:50+00:00

commit 6052a3110be208e547a4a8aeb184446199a16e8a upstream. 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: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Tested-by: Jian-Hong Pan Link: https://lore.kernel.org/r/20211117094527.146275-7-maxime@cerno.tech Signed-off-by: Greg Kroah-Hartman

drm/vc4: kms: Don't duplicate pending commit

2021-12-08T08:04:50+00:00

commit d354699e2292c60f25496d3c31ce4e7b1563b899 upstream. 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: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Tested-by: Jian-Hong Pan Link: https://lore.kernel.org/r/20211117094527.146275-6-maxime@cerno.tech Signed-off-by: Greg Kroah-Hartman

drm/vc4: kms: Clear the HVS FIFO commit pointer once done

2021-12-08T08:04:50+00:00

commit d134c5ff71c7f2320fc7997f2fbbdedf0c76889a upstream. Commit 9ec03d7f1ed3 ("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: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Tested-by: Jian-Hong Pan Link: https://lore.kernel.org/r/20211117094527.146275-5-maxime@cerno.tech Signed-off-by: Greg Kroah-Hartman

drm/vc4: kms: Add missing drm_crtc_commit_put

2021-12-08T08:04:50+00:00

commit 049cfff8d53a30cae3349ff71a4c01b7d9981bc2 upstream. Commit 9ec03d7f1ed3 ("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: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Tested-by: Jian-Hong Pan Link: https://lore.kernel.org/r/20211117094527.146275-4-maxime@cerno.tech Signed-off-by: Greg Kroah-Hartman

drm/vc4: kms: Fix return code check

2021-12-08T08:04:50+00:00

commit f927767978d201d4ac023fcd797adbb963a6565d upstream. 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: 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a commit") Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Tested-by: Jian-Hong Pan Link: https://lore.kernel.org/r/20211117094527.146275-3-maxime@cerno.tech Signed-off-by: Greg Kroah-Hartman

drm/vc4: kms: Wait for the commit before increasing our clock rate

2021-12-08T08:04:50+00:00

commit 0c980a006d3fbee86c4d0698f66d6f5381831787 upstream. 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: d7d96c00e585 ("drm/vc4: hvs: Boost the core clock during modeset") Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Tested-by: Jian-Hong Pan Link: https://lore.kernel.org/r/20211117094527.146275-2-maxime@cerno.tech Signed-off-by: Greg Kroah-Hartman

drm/vc4: fix error code in vc4_create_object()

2021-12-01T08:04:47+00:00

[ Upstream commit 96c5f82ef0a145d3e56e5b26f2bf6dcd2ffeae1c ] The ->gem_create_object() functions are supposed to return NULL if there is an error. None of the callers expect error pointers so returing one will lead to an Oops. See drm_gem_vram_create(), for example. Fixes: c826a6e10644 ("drm/vc4: Add a BO cache.") Signed-off-by: Dan Carpenter Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20211118111416.GC1147@kili Signed-off-by: Sasha Levin

drm/vc4: hdmi: Remove unused struct

2021-10-06T09:05:44+00:00

Commitc7d30623540b ("drm/vc4: hdmi: Remove unused struct") removed the references to the vc4_hdmi_audio_widgets and vc4_hdmi_audio_routes structures, but not the structures themselves resulting in two warnings. Remove it. Fixes: c7d30623540b ("drm/vc4: hdmi: Remove unused struct") Reported-by: kernel test robot Signed-off-by: Maxime Ripard Reviewed-by: Dave Stevenson Link: https://patchwork.freedesktop.org/patch/msgid/20210819140753.930751-1-maxime@cerno.tech Signed-off-by: Maarten Lankhorst

Revert "drm/vc4: hdmi: Remove drm_encoder->crtc usage"

2021-09-19T17:11:53+00:00

This reverts commit 27da370e0fb343a0baf308f503bb3e5dcdfe3362. Sudip Mukherjee reports that this broke pulseaudio with a NULL pointer dereference in vc4_hdmi_audio_prepare(), bisected it to this commit, and confirmed that a revert fixed the problem. Revert the problematic commit until fixed. Link: https://lore.kernel.org/all/CADVatmPB9-oKd=ypvj25UYysVo6EZhQ6bCM7EvztQBMyiZfAyw@mail.gmail.com/ Link: https://lore.kernel.org/all/CADVatmN5EpRshGEPS_JozbFQRXg5w_8LFB3OMP1Ai-ghxd3w4g@mail.gmail.com/ Reported-and-tested-by: Sudip Mukherjee Cc: Maxime Ripard Cc: Emma Anholt Cc: Dave Airlie Signed-off-by: Linus Torvalds

Revert drm/vc4 hdmi runtime PM changes

2021-09-19T17:06:46+00:00

This reverts commits 9984d6664ce9 ("drm/vc4: hdmi: Make sure the controller is powered in detect") 411efa18e4b0 ("drm/vc4: hdmi: Move the HSM clock enable to runtime_pm") as Michael Stapelberg reports that the new runtime PM changes cause his Raspberry Pi 3 to hang on boot, probably due to interactions with other changes in the DRM tree (because a bisect points to the merge in commit e058a84bfddc: "Merge tag 'drm-next-2021-07-01' of git://.../drm"). Revert these two commits until it's been resolved. Link: https://lore.kernel.org/all/871r5mp7h2.fsf@midna.i-did-not-set--mail-host-address--so-tickle-me/ Reported-and-tested-by: Michael Stapelberg Cc: Maxime Ripard Cc: Dave Stevenson Cc: Dave Airlie Signed-off-by: Linus Torvalds