The sampler must disable and re-enable counter sampling around
suspends, and must re-program the FW interface after a reset to
avoid losing data.
Signed-off-by: Lukas Zapolskas <lukas.zapols...@arm.com>
---
drivers/gpu/drm/panthor/panthor_device.c | 7 +-
drivers/gpu/drm/panthor/panthor_perf.c | 89 ++++++++++++++++++++++++
drivers/gpu/drm/panthor/panthor_perf.h | 6 ++
3 files changed, 101 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/panthor/panthor_device.c
b/drivers/gpu/drm/panthor/panthor_device.c
index ab3e65cc17bd..4bcf257e1403 100644
--- a/drivers/gpu/drm/panthor/panthor_device.c
+++ b/drivers/gpu/drm/panthor/panthor_device.c
@@ -139,6 +139,7 @@ static void panthor_device_reset_work(struct work_struct
*work)
if (!drm_dev_enter(&ptdev->base, &cookie))
return;
+ panthor_perf_pre_reset(ptdev);
panthor_sched_pre_reset(ptdev);
panthor_fw_pre_reset(ptdev, true);
panthor_mmu_pre_reset(ptdev);
@@ -148,6 +149,7 @@ static void panthor_device_reset_work(struct work_struct
*work)
ret = panthor_fw_post_reset(ptdev);
atomic_set(&ptdev->reset.pending, 0);
panthor_sched_post_reset(ptdev, ret != 0);
+ panthor_perf_post_reset(ptdev);
drm_dev_exit(cookie);
if (ret) {
@@ -503,8 +505,10 @@ int panthor_device_resume(struct device *dev)
ret = panthor_device_resume_hw_components(ptdev);
}
- if (!ret)
+ if (!ret) {
panthor_sched_resume(ptdev);
+ panthor_perf_resume(ptdev);
+ }
drm_dev_exit(cookie);
@@ -568,6 +572,7 @@ int panthor_device_suspend(struct device *dev)
/* We prepare everything as if we were resetting the GPU.
* The end of the reset will happen in the resume path though.
*/
+ panthor_perf_suspend(ptdev);
panthor_sched_suspend(ptdev);
panthor_fw_suspend(ptdev);
panthor_mmu_suspend(ptdev);
diff --git a/drivers/gpu/drm/panthor/panthor_perf.c
b/drivers/gpu/drm/panthor/panthor_perf.c
index fd16039d9244..512bbdb0aac1 100644
--- a/drivers/gpu/drm/panthor/panthor_perf.c
+++ b/drivers/gpu/drm/panthor/panthor_perf.c
@@ -1845,6 +1845,63 @@ void panthor_perf_session_destroy(struct panthor_file
*pfile, struct panthor_per
}
}
+/**
+ * panthor_perf_suspend - Prepare the performance counter subsystem for system
suspend.
+ * @ptdev: Panthor device.
+ *
+ * Indicate to the performance counters that the system is suspending.
+ *
+ * This function must not be used to handle MCU power state transitions: just
before MCU goes
+ * from on to any inactive state, an automatic sample will be performed by the
firmware, and
+ * the performance counter firmware state will be restored on warm boot.
+ *
+ */
+void panthor_perf_suspend(struct panthor_device *ptdev)
+{
+ int ret;
+ struct panthor_perf *perf = ptdev->perf;
+ struct panthor_perf_sampler *sampler;
+
+ if (!perf)
+ return;
+
+ sampler = &perf->sampler;
+
+ if (!atomic_read(&sampler->enabled_clients))
+ return;
+
+ ret = panthor_perf_fw_stop_sampling(sampler->ptdev);
+ if (ret)
+ drm_warn(&ptdev->base, "Could not stop sampling before suspend,
err = %d", ret);
+}
+
+/**
+ * panthor_perf_resume - Resume the performance counter subsystem after system
resumption.
+ * @ptdev: Panthor device.
+ *
+ * Indicate to the performance counters that the system has resumed. This must
not be used
+ * to handle MCU state transitions, for the same reasons as detailed in the
kerneldoc for
+ * @panthor_perf_suspend.
+ */
+void panthor_perf_resume(struct panthor_device *ptdev)
+{
+ int ret;
+ struct panthor_perf *perf = ptdev->perf;
+ struct panthor_perf_sampler *sampler;
+
+ if (!perf)
+ return;
+
+ sampler = &perf->sampler;
+
+ if (!atomic_read(&sampler->enabled_clients))
+ return;
+
+ ret = panthor_perf_fw_start_sampling(sampler->ptdev);
+ if (ret)
+ drm_warn(&ptdev->base, "Could not resume sampling, err = %d",
ret);
+}
+
/**
* panthor_perf_unplug - Terminate the performance counter subsystem.
* @ptdev: Panthor device.
@@ -1878,3 +1935,35 @@ void panthor_perf_unplug(struct panthor_device *ptdev)
ptdev->perf = NULL;
}
+
+void panthor_perf_pre_reset(struct panthor_device *ptdev)
+{
+ struct panthor_perf_sampler *sampler;
+
+ if (drm_WARN_ON_ONCE(&ptdev->base, !ptdev->perf))
+ return;
+
+ sampler = &ptdev->perf->sampler;
+
+ if (!atomic_read(&sampler->enabled_clients))
+ return;
+
+ panthor_perf_fw_stop_sampling(sampler->ptdev);
+}
+
+void panthor_perf_post_reset(struct panthor_device *ptdev)
+{
+ struct panthor_perf_sampler *sampler;
+
+ if (drm_WARN_ON_ONCE(&ptdev->base, !ptdev->perf))
+ return;
+
+ sampler = &ptdev->perf->sampler;
+
+ if (!atomic_read(&sampler->enabled_clients))
+ return;
+
+ panthor_perf_fw_write_sampler_config(sampler);
+
+ panthor_perf_fw_start_sampling(sampler->ptdev);
+}
diff --git a/drivers/gpu/drm/panthor/panthor_perf.h
b/drivers/gpu/drm/panthor/panthor_perf.h
index 5a14854368eb..1044b0a1cfaa 100644
--- a/drivers/gpu/drm/panthor/panthor_perf.h
+++ b/drivers/gpu/drm/panthor/panthor_perf.h
@@ -14,6 +14,8 @@ struct panthor_file;
struct panthor_perf;
int panthor_perf_init(struct panthor_device *ptdev);
+void panthor_perf_suspend(struct panthor_device *ptdev);
+void panthor_perf_resume(struct panthor_device *ptdev);
void panthor_perf_unplug(struct panthor_device *ptdev);
int panthor_perf_session_setup(struct drm_file *file, struct panthor_perf
*perf,
@@ -30,5 +32,9 @@ void panthor_perf_session_destroy(struct panthor_file *pfile,
struct panthor_per
void panthor_perf_report_irq(struct panthor_device *ptdev, u32 status);
+void panthor_perf_pre_reset(struct panthor_device *ptdev);
+
+void panthor_perf_post_reset(struct panthor_device *ptdev);
+
#endif /* __PANTHOR_PERF_H__ */
--
2.33.0.dirty
