linux.git/drivers/gpu/drm/panthor, branch v7.2-rc2

drm/panthor: Keep interrupts masked until they are needed

2026-06-30T14:26:55+00:00

The autogenerated panthor_request_xx_irq() helpers unmask Mali
interrupts before we're sure we'll have a handler registered. For
non-shared IRQ lines, that's fine, but for shared ones, it might cause
an interrupt flood if the HW block raises an interrupt for any reason.

We could reworking the calls in panthor_request_xx_irq(), but it's just
simpler to let the caller decide when they are ready to handle interrupts
and call panthor_pwr_irq_resume() themselves. While at it, rework the
prototype to let users call panthor_pwr_irq_enable_events() explicitly
instead of passing an initial mask to panthor_request_pwr_irq().

Fixes: 5fe909cae118 ("drm/panthor: Add the device logical block")
Reported-by: Shashiko 
Closes: https://sashiko.dev/#/patchset/20260623-panthor-signal-from-irq-v3-0-2ece396f8ee0@collabora.com?part=3
Signed-off-by: Boris Brezillon 
Reviewed-by: Karunika Choo 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-11-b67ed973fea6@collabora.com

drm/panthor: Interrupt group start/resumption if group_bind_locked() fails

2026-06-30T14:26:55+00:00

group_bind_locked() can fail if the MMU block is stuck. This is normally
a reset situation, but by the time we reset the GPU, we might have
tried to resume a group that's not resident, which will probably trip
out the FW. So let's avoid that by bailing out when group_bind_locked()
returns an error. We don't even try to start more groups because the
GPU will be reset anyway.

Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260623-panthor-signal-from-irq-v3-0-2ece396f8ee0@collabora.com?part=7
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-10-b67ed973fea6@collabora.com

drm/panthor: Fix a leak when a group is evicted before the tiler OOM is serviced

2026-06-30T14:26:55+00:00

A group ref is tied to the pending tiler_oom_work, so we need to release
it if the cancel was effective.

Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260623-panthor-signal-from-irq-v3-0-2ece396f8ee0@collabora.com?part=7
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-9-b67ed973fea6@collabora.com

drm/panthor: Drop a needless check in panthor_fw_unplug()

2026-06-30T14:26:55+00:00

panthor_fw_unplug() is only called if we at least managed to initialize
the IRQ, so it's safe to drop the "is IRQ initialized" check.

Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-8-b67ed973fea6@collabora.com

drm/panthor: Fix panthor_pwr_unplug()

2026-06-30T14:26:55+00:00

We can't call panthor_pwr_irq_suspend() if the device is suspended,
or this leads to a hang when the IOMEM region is accessed while the
clks are disabled. Do what other sub-components do and conditionally
call panthor_pwr_irq_suspend() if we know the PWR regbank block is
accessible.

Fixes: c27787f2b77f ("drm/panthor: Introduce panthor_pwr API and power control framework")
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-7-b67ed973fea6@collabora.com

drm/panthor: Don't overrule pending immediate ticks in sched_resume_tick()

2026-06-30T14:26:55+00:00

We schedule immediate ticks when we need to process events on CSGs,
but those immediate ticks don't change the resched_target because we
want the other groups to stay scheduled for the remaining of the GPU
timeslot they were given. Make sure these immediate ticks don't get
overruled by a sched_queue_delayed_work() that would delay the tick
execution.

Fixes: 99820b4b7e50 ("drm/panthor: Make sure we resume the tick when new jobs are submitted")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260625-panthor-signal-from-irq-v4-0-3d2908912afa@collabora.com?part=9
Signed-off-by: Boris Brezillon 
Reviewed-by: Karunika Choo 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-6-b67ed973fea6@collabora.com

drm/panthor: Fix theoretical IOMEM access in suspended state

2026-06-30T14:26:55+00:00

In theory, our hardirq handler can be called while the device (and
thus the panthor_irq) is suspended, because the IRQ line is shared.
In practice though, in all the designs we've seen, the line is only
shared within the GPU, and because sub-component suspend state is
consistent (all-suspended or all-resumed), we shouldn't end up with
an interrupt triggered while we're suspended.

Fix the problem anyway, if nothing else, for our sanity.

Fixes: 0b2d86670a84 ("drm/panthor: Rework panthor_irq::suspended into panthor_irq::state")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260625-panthor-signal-from-irq-v4-0-3d2908912afa@collabora.com?part=1
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-5-b67ed973fea6@collabora.com

drm/panthor: Fix potential invalid pointer deref in group_process_tiler_oom()

2026-06-30T14:26:55+00:00

If heaps is an ERR_PTR(), panthor_heap_pool_put() will deref an invalid
pointer. Make sure we set it to NULL in that case.

Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260625-panthor-signal-from-irq-v5-0-8836a74e0ef9@collabora.com?part=2
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-4-b67ed973fea6@collabora.com

drm/panthor: Keep the reset work disabled until everything is initialized

2026-06-30T14:26:55+00:00

The reset work will sub-component reset helpers, which might not be
ready if the reset happens during initialization, leading to NULL
pointer dereferences or worse.

Avoid that by keeping the reset work disabled while we're initializing
those sub-components.

Fixes: 5fe909cae118 ("drm/panthor: Add the device logical block")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260625-panthor-signal-from-irq-v5-0-8836a74e0ef9@collabora.com?part=4
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-2-b67ed973fea6@collabora.com

drm/panthor: Always use the IRQ-safe variant when acquiring the fence lock

2026-06-30T14:26:54+00:00

Since dma_fence objects can be shared with other subsystems, they may be
accessed from hardirq context in those drivers, and we have to take
that into account by also using the IRQ-safe variant when acquiring
the lock.

While at it, switch to the guard model.

Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260625-panthor-signal-from-irq-v5-0-8836a74e0ef9@collabora.com?part=11
Signed-off-by: Boris Brezillon 
Reviewed-by: Liviu Dudau 
Signed-off-by: Liviu Dudau 
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-1-b67ed973fea6@collabora.com