When we re-assign a slot to a different VM, we need to make sure the
old VM caches are flushed before doing the switch. Specialize
panthor_mmu_as_disable() so we can skip the slot programmation while
still getting the cache flushing, and call this helper from
panthor_vm_active() when an idle slot is recycled.
v2:
- Collect R-bs
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 | 26 ++++++++++++++++++++------
1 file changed, 20 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/panthor/panthor_mmu.c
b/drivers/gpu/drm/panthor/panthor_mmu.c
index 8ba5259e3d28..3644af1a8e56 100644
--- a/drivers/gpu/drm/panthor/panthor_mmu.c
+++ b/drivers/gpu/drm/panthor/panthor_mmu.c
@@ -585,7 +585,8 @@ static int panthor_mmu_as_enable(struct panthor_device
*ptdev, u32 as_nr,
return as_send_cmd_and_wait(ptdev, as_nr, AS_COMMAND_UPDATE);
}
-static int panthor_mmu_as_disable(struct panthor_device *ptdev, u32 as_nr)
+static int panthor_mmu_as_disable(struct panthor_device *ptdev, u32 as_nr,
+ bool recycle_slot)
{
int ret;
@@ -595,6 +596,12 @@ static int panthor_mmu_as_disable(struct panthor_device
*ptdev, u32 as_nr)
if (ret)
return ret;
+ /* If the slot is going to be used immediately, don't bother changing
+ * the config.
+ */
+ if (recycle_slot)
+ return 0;
+
gpu_write64(ptdev, AS_TRANSTAB(as_nr), 0);
gpu_write64(ptdev, AS_MEMATTR(as_nr), 0);
gpu_write64(ptdev, AS_TRANSCFG(as_nr), AS_TRANSCFG_ADRMODE_UNMAPPED);
@@ -714,6 +721,11 @@ int panthor_vm_active(struct panthor_vm *vm)
drm_WARN_ON(&ptdev->base,
refcount_read(&lru_vm->as.active_cnt));
as = lru_vm->as.id;
+
+ ret = panthor_mmu_as_disable(ptdev, as, true);
+ if (ret)
+ goto out_unlock;
+
panthor_vm_release_as_locked(lru_vm);
}
@@ -853,7 +865,7 @@ static void panthor_vm_declare_unusable(struct panthor_vm
*vm)
vm->unusable = true;
mutex_lock(&ptdev->mmu->as.slots_lock);
if (vm->as.id >= 0 && drm_dev_enter(&ptdev->base, &cookie)) {
- panthor_mmu_as_disable(ptdev, vm->as.id);
+ panthor_mmu_as_disable(ptdev, vm->as.id, false);
drm_dev_exit(cookie);
}
mutex_unlock(&ptdev->mmu->as.slots_lock);
@@ -1780,7 +1792,7 @@ static void panthor_mmu_irq_handler(struct panthor_device
*ptdev, u32 status)
ptdev->mmu->as.slots[as].vm->unhandled_fault = true;
/* Disable the MMU to kill jobs on this AS. */
- panthor_mmu_as_disable(ptdev, as);
+ panthor_mmu_as_disable(ptdev, as, false);
mutex_unlock(&ptdev->mmu->as.slots_lock);
status &= ~mask;
@@ -1809,7 +1821,8 @@ void panthor_mmu_suspend(struct panthor_device *ptdev)
struct panthor_vm *vm = ptdev->mmu->as.slots[i].vm;
if (vm) {
- drm_WARN_ON(&ptdev->base, panthor_mmu_as_disable(ptdev,
i));
+ drm_WARN_ON(&ptdev->base,
+ panthor_mmu_as_disable(ptdev, i, false));
panthor_vm_release_as_locked(vm);
}
}
@@ -1930,7 +1943,7 @@ static void panthor_vm_free(struct drm_gpuvm *gpuvm)
int cookie;
if (drm_dev_enter(&ptdev->base, &cookie)) {
- panthor_mmu_as_disable(ptdev, vm->as.id);
+ panthor_mmu_as_disable(ptdev, vm->as.id, false);
drm_dev_exit(cookie);
}
@@ -2790,7 +2803,8 @@ void panthor_mmu_unplug(struct panthor_device *ptdev)
struct panthor_vm *vm = ptdev->mmu->as.slots[i].vm;
if (vm) {
- drm_WARN_ON(&ptdev->base, panthor_mmu_as_disable(ptdev,
i));
+ drm_WARN_ON(&ptdev->base,
+ panthor_mmu_as_disable(ptdev, i, false));
panthor_vm_release_as_locked(vm);
}
}
--
2.51.1
