From: Boris Brezillon <[email protected]>

If we don't do that, we end up with invalid timestamps in the block
headers.

We also need to avoid the warning on the cycle counter reference being
other than 0 during device reset, because of perfcnt's lingering ref.

Ideally this would be dealt with by splitting the reset sequence into
pre and post stages, so that a hypothetical panfrost_perfcnt_pre_reset()
would release the cycle counter reference. In the absence thereof, we
just make do.

Fixes: 7786fd108777 ("drm/panfrost: Expose performance counters through 
unstable ioctls")
Signed-off-by: Boris Brezillon <[email protected]>
Signed-off-by: Adrián Larumbe <[email protected]>
---
 drivers/gpu/drm/panfrost/panfrost_gpu.c     | 6 +++---
 drivers/gpu/drm/panfrost/panfrost_perfcnt.c | 3 +++
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c 
b/drivers/gpu/drm/panfrost/panfrost_gpu.c
index 6081b27829e1..7d66b1b50968 100644
--- a/drivers/gpu/drm/panfrost/panfrost_gpu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
@@ -94,10 +94,10 @@ int panfrost_gpu_soft_reset(struct panfrost_device *pfdev)
                  GPU_IRQ_CLEAN_CACHES_COMPLETED);
 
        /*
-        * All in-flight jobs should have released their cycle
-        * counter references upon reset, but let us make sure
+        * Even though all in-flight jobs should have released their cycle 
counter
+        * references upon reset, perfcnt's might still hang about.
         */
-       if (drm_WARN_ON(&pfdev->base, 
atomic_read(&pfdev->cycle_counter.use_count) != 0))
+       if (atomic_read(&pfdev->cycle_counter.use_count) != 0)
                atomic_set(&pfdev->cycle_counter.use_count, 0);
 
        return 0;
diff --git a/drivers/gpu/drm/panfrost/panfrost_perfcnt.c 
b/drivers/gpu/drm/panfrost/panfrost_perfcnt.c
index a9def452d5ef..b26da057a1a0 100644
--- a/drivers/gpu/drm/panfrost/panfrost_perfcnt.c
+++ b/drivers/gpu/drm/panfrost/panfrost_perfcnt.c
@@ -17,6 +17,7 @@
 #include "panfrost_device.h"
 #include "panfrost_features.h"
 #include "panfrost_gem.h"
+#include "panfrost_gpu.h"
 #include "panfrost_issues.h"
 #include "panfrost_job.h"
 #include "panfrost_mmu.h"
@@ -52,6 +53,7 @@ static void panfrost_perfcnt_hw_disable(struct 
panfrost_device *pfdev)
        gpu_write(pfdev, GPU_PRFCNT_TILER_EN, 0);
 
        if (perfcnt->owns_as_ref) {
+               panfrost_cycle_counter_put(pfdev);
                panfrost_mmu_as_put(pfdev, perfcnt->mapping->mmu);
                perfcnt->owns_as_ref = false;
        }
@@ -84,6 +86,7 @@ static int panfrost_perfcnt_hw_enable(struct panfrost_device 
*pfdev)
                return ret;
 
        perfcnt->owns_as_ref = true;
+       panfrost_cycle_counter_get(pfdev);
 
        as = ret;
        cfg = GPU_PERFCNT_CFG_AS(as) |

-- 
2.56.0

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