| Message ID | 20230807000444.14926-1-dmitry.osipenko@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4] drm/panfrost: Sync IRQ by job's timeout handler | expand |
On Mon, 7 Aug 2023 03:04:44 +0300 Dmitry Osipenko <dmitry.osipenko@collabora.com> wrote: > Panfrost IRQ handler may stuck for a long time, for example this happens > when there is a bad HDMI connection and HDMI handler takes a long time to > finish processing, holding Panfrost. Make Panfrost's job timeout handler > to sync IRQ before checking fence signal status in order to prevent > spurious job timeouts due to a slow IRQ processing. > > Reviewed-by: Steven Price <steven.price@arm.com> > Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> > Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> > Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> # MediaTek MT8192 and MT8195 Chromebooks > Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Queued to drm-misc-next. Thanks, Boris > --- > > Changelog: > > v4: - Improved comment like was suggested by Boris and added his r-b. > > v3: - Added comment to the code as was suggested by Boris > > - Added r-b/t-b from Steven and Angelo > > v2: - Moved synchronize_irq() after first signal-check to avoid unnecessary > blocking on syncing. > > - Added warn message about high interrupt latency. > > drivers/gpu/drm/panfrost/panfrost_job.c | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c > index dbc597ab46fb..db6d9a17004f 100644 > --- a/drivers/gpu/drm/panfrost/panfrost_job.c > +++ b/drivers/gpu/drm/panfrost/panfrost_job.c > @@ -720,6 +720,22 @@ static enum drm_gpu_sched_stat panfrost_job_timedout(struct drm_sched_job > if (dma_fence_is_signaled(job->done_fence)) > return DRM_GPU_SCHED_STAT_NOMINAL; > > + /* > + * Panfrost IRQ handler may take a long time to process an interrupt > + * if there is another IRQ handler hogging the processing. > + * For example, the HDMI encoder driver might be stuck in the IRQ > + * handler for a significant time in a case of bad cable connection. > + * In order to catch such cases and not report spurious Panfrost > + * job timeouts, synchronize the IRQ handler and re-check the fence > + * status. > + */ > + synchronize_irq(pfdev->js->irq); > + > + if (dma_fence_is_signaled(job->done_fence)) { > + dev_warn(pfdev->dev, "unexpectedly high interrupt latency\n"); > + return DRM_GPU_SCHED_STAT_NOMINAL; > + } > + > dev_err(pfdev->dev, "gpu sched timeout, js=%d, config=0x%x, status=0x%x, head=0x%x, tail=0x%x, sched_job=%p", > js, > job_read(pfdev, JS_CONFIG(js)),
diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index dbc597ab46fb..db6d9a17004f 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -720,6 +720,22 @@ static enum drm_gpu_sched_stat panfrost_job_timedout(struct drm_sched_job if (dma_fence_is_signaled(job->done_fence)) return DRM_GPU_SCHED_STAT_NOMINAL; + /* + * Panfrost IRQ handler may take a long time to process an interrupt + * if there is another IRQ handler hogging the processing. + * For example, the HDMI encoder driver might be stuck in the IRQ + * handler for a significant time in a case of bad cable connection. + * In order to catch such cases and not report spurious Panfrost + * job timeouts, synchronize the IRQ handler and re-check the fence + * status. + */ + synchronize_irq(pfdev->js->irq); + + if (dma_fence_is_signaled(job->done_fence)) { + dev_warn(pfdev->dev, "unexpectedly high interrupt latency\n"); + return DRM_GPU_SCHED_STAT_NOMINAL; + } + dev_err(pfdev->dev, "gpu sched timeout, js=%d, config=0x%x, status=0x%x, head=0x%x, tail=0x%x, sched_job=%p", js, job_read(pfdev, JS_CONFIG(js)),