An AS can be disabled in the middle of a VM operation (VM being
evicted from an AS slot, for instance). In that case, we need the
locked section to be unlocked before releasing the slot.
v2:
- Add an lockdep_assert_held() in panthor_mmu_as_disable()
- Collect R-bs
v3:
- Don't reset the locked_region range in the as_disable() path
Fixes: 6e2d3b3e8589 ("drm/panthor: Add support for atomic page table updates")
Signed-off-by: Boris Brezillon <[email protected]>
Reviewed-by: Liviu Dudau <[email protected]>
Reviewed-by: Chia-I Wu <[email protected]>
---
drivers/gpu/drm/panthor/panthor_mmu.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c
b/drivers/gpu/drm/panthor/panthor_mmu.c
index 3644af1a8e56..ca112d874ecb 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -588,14 +588,24 @@ static int panthor_mmu_as_enable(struct panthor_device
*ptdev, u32 as_nr,
static int panthor_mmu_as_disable(struct panthor_device *ptdev, u32 as_nr,
bool recycle_slot)
{
+ struct panthor_vm *vm = ptdev->mmu->as.slots[as_nr].vm;
int ret;
+ lockdep_assert_held(&ptdev->mmu->as.slots_lock);
+
/* Flush+invalidate RW caches, invalidate RO ones. */
ret = panthor_gpu_flush_caches(ptdev, CACHE_CLEAN | CACHE_INV,
CACHE_CLEAN | CACHE_INV, CACHE_INV);
if (ret)
return ret;
+ if (vm && vm->locked_region.size) {
+ /* Unlock the region if there's a lock pending. */
+ ret = as_send_cmd_and_wait(ptdev, vm->as.id, AS_COMMAND_UNLOCK);
+ if (ret)
+ return ret;
+ }
+
/* If the slot is going to be used immediately, don't bother changing
* the config.
*/
--
2.51.1
