virtio core already sets the .owner, so driver does not need to.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Message-Id: <20240331-module-owner-virtio-v2-2-98f04bfaf46a@linaro.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Treat stats requests as wakeup events to ensure that the driver responds
to device requests in a timely manner.
Signed-off-by: David Stevens <stevensd@chromium.org>
Acked-by: David Hildenbrand <david@redhat.com>
Message-Id: <20240321012445.1593685-3-stevensd@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Wakeup sources don't support nesting multiple events, so sharing a
single object between multiple drivers can result in one driver
overriding the wakeup event processing period specified by another
driver. Have the virtio balloon driver use the wakeup source of the
device it is bound to rather than the wakeup source of the parent
device, to avoid conflicts with the transport layer.
Note that although the virtio balloon's virtio_device itself isn't what
actually wakes up the device, it is responsible for processing wakeup
events. In the same way that EPOLLWAKEUP uses a dedicated wakeup_source
to prevent suspend when userspace is processing wakeup events, a
dedicated wakeup_source is necessary when processing wakeup events in a
higher layer in the kernel.
Fixes: b12fbc3f78 ("virtio_balloon: stay awake while adjusting balloon")
Signed-off-by: David Stevens <stevensd@chromium.org>
Acked-by: David Hildenbrand <david@redhat.com>
Message-Id: <20240321012445.1593685-2-stevensd@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
With virtio-mem, primarily hibernation is problematic: as the machine shuts
down, the virtio-mem device loses its state. Powering the machine back up
is like losing a bunch of DIMMs. While there would be ways to add limited
support, suspend+resume is more commonly used for VMs and "easier" to
support cleanly.
s2idle can be supported without any device dependencies. Similarly, one
would expect suspend-to-ram (i.e., S3) to work out of the box. However,
QEMU currently unplugs all device memory when resuming the VM, using a
cold reset on the "wakeup" path. In order to support S3, we need a feature
flag for the device to tell us if memory remains plugged when waking up. In
the future, QEMU will implement this feature.
So let's always support s2idle and support S3 with plugged memory only if
the device indicates support. Block hibernation early using the PM
notifier.
Trying to hibernate now fails early:
# echo disk > /sys/power/state
[ 26.455369] PM: hibernation: hibernation entry
[ 26.458271] virtio_mem virtio0: hibernation is not supported.
[ 26.462498] PM: hibernation: hibernation exit
-bash: echo: write error: Operation not permitted
s2idle works even without the new feature bit:
# echo s2idle > /sys/power/mem_sleep
# echo mem > /sys/power/state
[ 52.083725] PM: suspend entry (s2idle)
[ 52.095950] Filesystems sync: 0.010 seconds
[ 52.101493] Freezing user space processes
[ 52.104213] Freezing user space processes completed (elapsed 0.001 seconds)
[ 52.106520] OOM killer disabled.
[ 52.107655] Freezing remaining freezable tasks
[ 52.110880] Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
[ 52.113296] printk: Suspending console(s) (use no_console_suspend to debug)
S3 does not work without the feature bit when memory is plugged:
# echo deep > /sys/power/mem_sleep
# echo mem > /sys/power/state
[ 32.788281] PM: suspend entry (deep)
[ 32.816630] Filesystems sync: 0.027 seconds
[ 32.820029] Freezing user space processes
[ 32.823870] Freezing user space processes completed (elapsed 0.001 seconds)
[ 32.827756] OOM killer disabled.
[ 32.829608] Freezing remaining freezable tasks
[ 32.833842] Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
[ 32.837953] printk: Suspending console(s) (use no_console_suspend to debug)
[ 32.916172] virtio_mem virtio0: suspend+resume with plugged memory is not supported
[ 32.916181] virtio-pci 0000:00:02.0: PM: pci_pm_suspend(): virtio_pci_freeze+0x0/0x50 returns -1
[ 32.916197] virtio-pci 0000:00:02.0: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x170 returns -1
[ 32.916210] virtio-pci 0000:00:02.0: PM: failed to suspend async: error -1
But S3 works with the new feature bit when memory is plugged (patched
QEMU):
# echo deep > /sys/power/mem_sleep
# echo mem > /sys/power/state
[ 33.983694] PM: suspend entry (deep)
[ 34.009828] Filesystems sync: 0.024 seconds
[ 34.013589] Freezing user space processes
[ 34.016722] Freezing user space processes completed (elapsed 0.001 seconds)
[ 34.019092] OOM killer disabled.
[ 34.020291] Freezing remaining freezable tasks
[ 34.023549] Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
[ 34.026090] printk: Suspending console(s) (use no_console_suspend to debug)
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20240318120645.105664-1-david@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This removes the signal/coredump hacks added for vhost_tasks in:
Commit f9010dbdce ("fork, vhost: Use CLONE_THREAD to fix freezer/ps regression")
When that patch was added vhost_tasks did not handle SIGKILL and would
try to ignore/clear the signal and continue on until the device's close
function was called. In the previous patches vhost_tasks and the vhost
drivers were converted to support SIGKILL by cleaning themselves up and
exiting. The hacks are no longer needed so this removes them.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-10-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Instead of lingering until the device is closed, this has us handle
SIGKILL by:
1. marking the worker as killed so we no longer try to use it with
new virtqueues and new flush operations.
2. setting the virtqueue to worker mapping so no new works are queued.
3. running all the exiting works.
Suggested-by: Edward Adam Davis <eadavis@qq.com>
Reported-and-tested-by: syzbot+98edc2df894917b3431f@syzkaller.appspotmail.com
Message-Id: <tencent_546DA49414E876EEBECF2C78D26D242EE50A@qq.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-9-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In the next patches where the worker can be killed while in use, we
need to be able to take the worker mutex and kill queued works for
new IO and flushes, and set some new flags to prevent new
__vhost_vq_attach_worker calls from swapping in/out killed workers.
If we are holding the worker mutex during a flush and the flush's work
is still in the queue, the worker code that will handle the SIGKILL
cleanup won't be able to take the mutex and perform it's cleanup. So
this patch has us drop the worker mutex while waiting for the flush
to complete.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-8-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
__vhost_vq_attach_worker uses the vhost_dev mutex to serialize the
swapping of a virtqueue's worker. This was done for simplicity because
we are already holding that mutex.
In the next patches where the worker can be killed while in use, we need
finer grained locking because some drivers will hold the vhost_dev mutex
while flushing. However in the SIGKILL handler in the next patches, we
will need to be able to swap workers (set current one to NULL), kill
queued works and stop new flushes while flushes are in progress.
To prepare us, this has us use the virtqueue mutex for swapping workers
instead of the vhost_dev one.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-7-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vhost_vq_work_queue will never fail when queueing the TMF's response
handling because a guest can only send us TMFs when the device is fully
setup so there is always a worker at that time. In the next patches we
will modify the worker code so it handles SIGKILL by exiting before
outstanding commands/TMFs have sent their responses. In that case
vhost_vq_work_queue can fail when we try to send a response.
This has us just free the TMF's resources since at this time the guest
won't be able to get a response even if we could send it.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-6-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vhost_vq_flush is no longer used so remove it.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-5-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We flush all the workers that are not also used by the ctl vq to make
sure that responses queued by LIO before the TMF response are sent
before the TMF response. This requires a special vhost_vq_flush
function which, in the next patches where we handle SIGKILL killing
workers while in use, will require extra locking/complexity. To avoid
that, this patch has us flush the entire device from the system work
queue, then queue up sending the response from there.
This is a little less optimal since we now flush all workers but this
will be ok since commands have already timed out and perf is not a
concern.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-4-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In the next patches we will support the vhost_task being killed while in
use. The problem for vhost-scsi is that we can't free some structs until
we get responses for commands we have submitted to the target layer and
we currently process the responses from the vhost_task.
This has just drop the responses and free the command's resources. When
all commands have completed then operations like flush will be woken up
and we can complete device release and endpoint cleanup.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-3-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently, we can try to queue an event's work before the vhost_task is
created. When this happens we just drop it in vhost_scsi_do_plug before
even calling vhost_vq_work_queue. During a device shutdown we do the
same thing after vhost_scsi_clear_endpoint has cleared the backends.
In the next patches we will be able to kill the vhost_task before we
have cleared the endpoint. In that case, vhost_vq_work_queue can fail
and we will leak the event's memory. This has handle the failure by
just freeing the event. This is safe to do, because
vhost_vq_work_queue will only return failure for us when the vhost_task
is killed and so userspace will not be able to handle events if we
sent them.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20240316004707.45557-2-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Per filesystems/sysfs.rst, show() should only use sysfs_emit()
or sysfs_emit_at() when formatting the value to be returned to user space.
coccinelle complains that there are still a couple of functions that use
snprintf(). Convert them to sysfs_emit().
sprintf() will be converted as weel if they have.
Generally, this patch is generated by
make coccicheck M=<path/to/file> MODE=patch \
COCCI=scripts/coccinelle/api/device_attr_show.cocci
No functional change intended
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Jason Wang <jasowang@redhat.com>
CC: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
CC: virtualization@lists.linux.dev
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Message-Id: <20240314095853.1326111-1-lizhijian@fujitsu.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In the vp_vdpa_set_status function, when setting the device status to
VIRTIO_CONFIG_S_DRIVER_OK, the vp_vdpa_request_irq function may fail.
In such cases, the device status should not be set to DRIVER_OK. Add
exception printing to remind the user.
Signed-off-by: Yuxue Liu <yuxue.liu@jaguarmicro.com>
Message-Id: <20240325105448.235-1-gavin.liu@jaguarmicro.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In some scenarios, the DPT object gets shrunk but
the actual framebuffer did not and thus its still
there on the DPT's vm->bound_list. Then it tries to
rewrite the PTEs via a stale CPU mapping. This causes panic.
Cc: stable@vger.kernel.org
Reported-by: Shawn Lee <shawn.c.lee@intel.com>
Fixes: 0dc987b699 ("drm/i915/display: Add smem fallback allocation for dpt")
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
[vsyrjala: Add TODO comment]
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240520165634.1162470-1-vidya.srinivas@intel.com
i915 display calls this when releasing the drm_device, match this also
in xe by using drmm. intel_display_device_remove() is freeing purely
software state for the drm_device.
v2: fix build error
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-36-matthew.auld@intel.com
Match the i915 display handling here with calling both no_irq and
noaccel when removing the device.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-34-matthew.auld@intel.com
Set our various mmio mappings to NULL. This should make it easier to
catch something rogue trying to mess with mmio after device removal. For
example, we might unmap everything and then start hitting some mmio
address which has already been unmamped by us and then remapped by
something else, causing all kinds of carnage.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-33-matthew.auld@intel.com
Not valid to touch mmio once the device is removed, so make sure we
unmap on removal and not just when driver instance goes away. Also set
the mmio pointers to NULL to hopefully catch such issues more easily.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-32-matthew.auld@intel.com
No need to hand roll the onion unwind here, just move gt_remove over to
devm which will already have the correct ordering.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-31-matthew.auld@intel.com
Here we are using drmm to ensure we release the coredump when unloading
the module, however the coredump is very much tied to the struct device
underneath. We can see this when we hotunplug the device, for which we
have already got a coredump attached. In such a case the coredump still
remains and adding another is not possible. However we still register
the release action via xe_driver_devcoredump_fini(), so in effect two or
more releases for one dump. The other consideration is that the
coredump state is embedded in the xe_driver instance, so technically
once the drmm release action fires we might free the coredumpe state
from a different driver instance, assuming we have two release actions
and they can race. Rather use devm here to remove the coredump when the
device is released.
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1679
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-29-matthew.auld@intel.com
Here we are touching the HW/GuC and presumably this should happen when
the device is removed. Currently if you hotunplug the device this is
skipped if there is already open driver instance.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-24-matthew.auld@intel.com
Make sure to actually call this when the device is removed. Currently we
only trigger it when the driver instance goes away, but that doesn't
work too well with hotunplug, since device can be removed and re-probed
with a new driver instance, where the guc_fini() is called too late.
Move the fini over to devm to ensure this is called when device is
removed.
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1717
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-22-matthew.auld@intel.com
Device can be hotunplugged before we start destroying gem objects. In
such a case don't touch the GGTT entries, trigger any invalidations or
mess around with rpm. This should already be taken care of when
removing the device, we just need to take care of dealing with the
software state, like removing the mm node.
v2: (Andrzej)
- Avoid some duplication by tracking the bound status and checking
that instead.
References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1717
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: Jagmeet Randhawa <jagmeet.randhawa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-21-matthew.auld@intel.com
This is quite broken since we are nuking the pdev link to the private
driver struct, but note here that driver_release is called when the
drm_device is released (poor mans drmm), which can be long after the
device has been removed. So here what we are actually doing is nuking
the pdev link for what is potentially bound to a different drm_device.
If that happens before our pci remove callback is triggered (for the new
drm_device) we silently exit and skip some important cleanup steps,
resulting in hilarity.
There should be no reason to implement driver_release, when we already
have nicer stuff like drmm, so just remove completely. The actual pdev
link is already nuked when removing the device.
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Andrzej Hajda <andrzej.hajda@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522102143.128069-19-matthew.auld@intel.com
TIF_FOREIGN_FPSTATE is a 'convenience' flag that should reflect whether
the current CPU holds the most recent user mode FP/SIMD state of the
current task. It combines two conditions:
- whether the current CPU's FP/SIMD state belongs to the task;
- whether that state is the most recent associated with the task (as a
task may have executed on other CPUs as well).
When a task is scheduled in and TIF_KERNEL_FPSTATE is set, it means the
task was in a kernel mode NEON section when it was scheduled out, and so
the kernel mode FP/SIMD state is restored. Since this implies that the
current CPU is *not* holding the most recent user mode FP/SIMD state of
the current task, the TIF_FOREIGN_FPSTATE flag is set too, so that the
user mode FP/SIMD state is reloaded from memory when returning to
userland.
However, the task may be scheduled out after completing the kernel mode
NEON section, but before returning to userland. When this happens, the
TIF_FOREIGN_FPSTATE flag will not be preserved, but will be set as usual
the next time the task is scheduled in, and will be based on the above
conditions.
This means that, rather than setting TIF_FOREIGN_FPSTATE when scheduling
in a task with TIF_KERNEL_FPSTATE set, the underlying state should be
updated so that TIF_FOREIGN_FPSTATE will assume the expected value as a
result.
So instead, call fpsimd_flush_cpu_state(), which takes care of this.
Closes: https://lore.kernel.org/all/cb8822182231850108fa43e0446a4c7f@kernel.org
Reported-by: Johannes Nixdorf <mixi@shadowice.org>
Fixes: aefbab8e77 ("arm64: fpsimd: Preserve/restore kernel mode NEON at context switch")
Cc: Mark Brown <broonie@kernel.org>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Janne Grunau <j@jannau.net>
Cc: stable@vger.kernel.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Janne Grunau <j@jannau.net>
Tested-by: Johannes Nixdorf <mixi@shadowice.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240522091335.335346-2-ardb+git@google.com
Signed-off-by: Will Deacon <will@kernel.org>
This reverts commit b8995a1841.
Ard managed to reproduce the dm-crypt corruption problem and got to the
bottom of it, so re-apply the problematic patch in preparation for
fixing things properly.
Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
The GuC firmware is loaded and initialized by the PF driver. Make
sure VF drivers only perform permitted operations. For submission
initialization, use number of GuC context IDs from self config.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240521092518.624-3-michal.wajdeczko@intel.com
While PF and native drivers may initialize submission code to use
all available GuC contexts IDs, the VF driver may only use limited
number of IDs. Update init function to accept number of context
IDs available for use.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240521092518.624-2-michal.wajdeczko@intel.com
We don't need <linux/delay.h> include since commit 5c09bd6ccd
("drm/xe/mmio: Move xe_mmio_wait32() to xe_mmio.c").
We don't need <linux/io-64-nonatomic-lo-hi.h> include since commit
54c659660d ("drm/xe: Make xe_mmio_read|write() functions non-inline").
And since commit 924e6a9789 ("drm/xe/uapi: Remove MMIO ioctl")
we don't need forward declarations of drm_device and drm_file.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240520181814.2392-4-michal.wajdeczko@intel.com
These compilation units use udelay() or some GT oriented printk
functions without explicitly including proper header files, and
relying on #includes from the xe_mmio.h instead. Fix that.
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Francois Dugast <francois.dugast@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240520181814.2392-3-michal.wajdeczko@intel.com
When the system power resumes, the TTL input of IT6505 may experience
some noise before the video signal stabilizes, necessitating a video
reset. This patch is implemented to prevent a loop of video error
interrupts, which can occur when a video reset in the video FIFO error
interrupt triggers another such interrupt. The patch processes the SCDT
and FIFO error interrupts simultaneously and ignores any video FIFO
error interrupts caused by a video reset.
Fixes: b5c84a9edc ("drm/bridge: add it6505 driver")
Signed-off-by: Kuro Chung <kuro.chung@ite.com.tw>
Signed-off-by: Hermes Wu <hermes.wu@ite.com.tw>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240522065528.1053439-1-kuro.chung@ite.com.tw