diff options
| author | Karunika Choo <karunika.choo@arm.com> | 2025-08-07 17:26:31 +0100 |
|---|---|---|
| committer | Steven Price <steven.price@arm.com> | 2025-08-15 10:52:26 +0100 |
| commit | e322a4844811b54477b7072eb40dc9e402a1725d (patch) | |
| tree | 6c7b1a28fa6f065f9c11f45cda92f2ec32455d1e | |
| parent | 3b1dc21d6d800cb86c1ef0c97968f5c783343f2b (diff) | |
drm/panthor: Serialize GPU cache flush operations
In certain scenarios, it is possible for multiple cache flushes to be
requested before the previous one completes. This patch introduces the
cache_flush_lock mutex to serialize these operations and ensure that
any requested cache flushes are completed instead of dropped.
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Co-developed-by: Dennis Tsiang <dennis.tsiang@arm.com>
Signed-off-by: Dennis Tsiang <dennis.tsiang@arm.com>
Signed-off-by: Karunika Choo <karunika.choo@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/20250807162633.3666310-6-karunika.choo@arm.com
| -rw-r--r-- | drivers/gpu/drm/panthor/panthor_gpu.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/gpu/drm/panthor/panthor_gpu.c b/drivers/gpu/drm/panthor/panthor_gpu.c index 5e2c3173ae27..db69449a5be0 100644 --- a/drivers/gpu/drm/panthor/panthor_gpu.c +++ b/drivers/gpu/drm/panthor/panthor_gpu.c @@ -35,6 +35,9 @@ struct panthor_gpu { /** @reqs_acked: GPU request wait queue. */ wait_queue_head_t reqs_acked; + + /** @cache_flush_lock: Lock to serialize cache flushes */ + struct mutex cache_flush_lock; }; #define GPU_INTERRUPTS_MASK \ @@ -110,6 +113,7 @@ int panthor_gpu_init(struct panthor_device *ptdev) spin_lock_init(&gpu->reqs_lock); init_waitqueue_head(&gpu->reqs_acked); + mutex_init(&gpu->cache_flush_lock); ptdev->gpu = gpu; dma_set_max_seg_size(ptdev->base.dev, UINT_MAX); @@ -258,6 +262,9 @@ int panthor_gpu_flush_caches(struct panthor_device *ptdev, bool timedout = false; unsigned long flags; + /* Serialize cache flush operations. */ + guard(mutex)(&ptdev->gpu->cache_flush_lock); + spin_lock_irqsave(&ptdev->gpu->reqs_lock, flags); if (!drm_WARN_ON(&ptdev->base, ptdev->gpu->pending_reqs & GPU_IRQ_CLEAN_CACHES_COMPLETED)) { |