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 <[email protected]> --- drivers/gpu/drm/panthor/panthor_device.c | 7 ++- drivers/gpu/drm/panthor/panthor_perf.c | 71 ++++++++++++++++++++++++ drivers/gpu/drm/panthor/panthor_perf.h | 6 ++ 3 files changed, 83 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c index 3063ffbead45..e6e279d91eae 100644 --- a/drivers/gpu/drm/panthor/panthor_device.c +++ b/drivers/gpu/drm/panthor/panthor_device.c @@ -162,6 +162,7 @@ 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); @@ -171,6 +172,7 @@ 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) { @@ -549,8 +551,10 @@ 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); @@ -614,6 +618,7 @@ 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 e8f26805fe3a..208f93d516d4 100644 --- a/drivers/gpu/drm/panthor/panthor_perf.c +++ b/drivers/gpu/drm/panthor/panthor_perf.c @@ -1894,6 +1894,53 @@ 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) +{ + struct panthor_perf *perf = ptdev->perf; + int ret; + + if (!perf) + return; + + ret = sampler_disable(&perf->sampler); + + 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) +{ + struct panthor_perf *perf = ptdev->perf; + int ret; + + if (!perf) + return; + + ret = sampler_enable(&perf->sampler); + + if (ret) + drm_warn(&ptdev->base, "Could not resume sampling, err = %d", ret); +} + /** * panthor_perf_unplug - Terminate the performance counter subsystem. * @ptdev: Panthor device. @@ -1927,3 +1974,27 @@ 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; + + sampler_disable(sampler); +} + +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; + + sampler_enable(sampler); +} 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
