On Wed, 23 Jul 2025, Dibin Moolakadan Subrahmanian <dibin.moolakadan.subrahman...@intel.com> wrote: > It has been observed that during `xe_display_pm_suspend()` execution, > an HPD interrupt can still be triggered, resulting in `dig_port_work` > being scheduled. The issue arises when this work executes after > `xe_display_pm_suspend_late()`, by which time the display is fully > suspended. > > This can lead to errors such as "DC state mismatch", as the dig_port > work accesses display resources that are no longer available or > powered. > > To address this, introduce 'intel_encoder_block_all_hpds' and > 'intel_encoder_unblock_all_hpds' functions, which iterate over all > encoders and block/unblock HPD respectively.
Please do not add anything xe specific to the display init/uninit/suspend/resume sequences. All of this needs to move to common display code under i915/display, and be shared between drivers. BR, Jani. > > These are used to: > - Block HPD IRQs before calling 'intel_hpd_cancel_work' in suspend > and shutdown > - Unblock HPD IRQs after 'intel_hpd_init' in resume > > This will prevent 'dig_port_work' being scheduled during display > suspend. > > Continuation of previous patch discussion: > https://patchwork.freedesktop.org/patch/663964/ > > Changes in v2: > - Add 'intel_encoder_block_all_hpds' to 'xe_display_pm_shutdown' > - Add 'intel_hpd_cancel_work' to 'xe_display_fini_early' to cancel > any HPD pending work at late driver removal > > Signed-off-by: Dibin Moolakadan Subrahmanian > <dibin.moolakadan.subrahman...@intel.com> > --- > drivers/gpu/drm/i915/display/intel_encoder.c | 23 ++++++++++++++++++++ > drivers/gpu/drm/i915/display/intel_encoder.h | 3 +++ > drivers/gpu/drm/i915/display/intel_hotplug.c | 2 -- > drivers/gpu/drm/xe/display/xe_display.c | 6 +++++ > 4 files changed, 32 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_encoder.c > b/drivers/gpu/drm/i915/display/intel_encoder.c > index 0b7bd26f4339..4e2b77b87678 100644 > --- a/drivers/gpu/drm/i915/display/intel_encoder.c > +++ b/drivers/gpu/drm/i915/display/intel_encoder.c > @@ -8,6 +8,7 @@ > #include "intel_display_core.h" > #include "intel_display_types.h" > #include "intel_encoder.h" > +#include "intel_hotplug.h" > > static void intel_encoder_link_check_work_fn(struct work_struct *work) > { > @@ -37,6 +38,28 @@ void intel_encoder_link_check_queue_work(struct > intel_encoder *encoder, int dela > &encoder->link_check_work, msecs_to_jiffies(delay_ms)); > } > > +void intel_encoder_unblock_all_hpds(struct intel_display *display) > +{ > + struct intel_encoder *encoder; > + > + if (!HAS_DISPLAY(display)) > + return; > + > + for_each_intel_encoder(display->drm, encoder) > + intel_hpd_unblock(encoder); > +} > + > +void intel_encoder_block_all_hpds(struct intel_display *display) > +{ > + struct intel_encoder *encoder; > + > + if (!HAS_DISPLAY(display)) > + return; > + > + for_each_intel_encoder(display->drm, encoder) > + intel_hpd_block(encoder); > +} > + > void intel_encoder_suspend_all(struct intel_display *display) > { > struct intel_encoder *encoder; > diff --git a/drivers/gpu/drm/i915/display/intel_encoder.h > b/drivers/gpu/drm/i915/display/intel_encoder.h > index 3fa5589f0b1c..e1d3aeab7c00 100644 > --- a/drivers/gpu/drm/i915/display/intel_encoder.h > +++ b/drivers/gpu/drm/i915/display/intel_encoder.h > @@ -17,4 +17,7 @@ void intel_encoder_link_check_flush_work(struct > intel_encoder *encoder); > void intel_encoder_suspend_all(struct intel_display *display); > void intel_encoder_shutdown_all(struct intel_display *display); > > +void intel_encoder_block_all_hpds(struct intel_display *display); > +void intel_encoder_unblock_all_hpds(struct intel_display *display); > + > #endif /* __INTEL_ENCODER_H__ */ > diff --git a/drivers/gpu/drm/i915/display/intel_hotplug.c > b/drivers/gpu/drm/i915/display/intel_hotplug.c > index 265aa97fcc75..c69b535497bf 100644 > --- a/drivers/gpu/drm/i915/display/intel_hotplug.c > +++ b/drivers/gpu/drm/i915/display/intel_hotplug.c > @@ -971,8 +971,6 @@ void intel_hpd_cancel_work(struct intel_display *display) > > spin_lock_irq(&display->irq.lock); > > - drm_WARN_ON(display->drm, get_blocked_hpd_pin_mask(display)); > - > display->hotplug.long_hpd_pin_mask = 0; > display->hotplug.short_hpd_pin_mask = 0; > display->hotplug.event_bits = 0; > diff --git a/drivers/gpu/drm/xe/display/xe_display.c > b/drivers/gpu/drm/xe/display/xe_display.c > index e2e0771cf274..9e984a045059 100644 > --- a/drivers/gpu/drm/xe/display/xe_display.c > +++ b/drivers/gpu/drm/xe/display/xe_display.c > @@ -96,6 +96,7 @@ static void xe_display_fini_early(void *arg) > if (!xe->info.probe_display) > return; > > + intel_hpd_cancel_work(display); > intel_display_driver_remove_nogem(display); > intel_display_driver_remove_noirq(display); > intel_opregion_cleanup(display); > @@ -340,6 +341,8 @@ void xe_display_pm_suspend(struct xe_device *xe) > > xe_display_flush_cleanup_work(xe); > > + intel_encoder_block_all_hpds(display); > + > intel_hpd_cancel_work(display); > > if (has_display(xe)) { > @@ -369,6 +372,7 @@ void xe_display_pm_shutdown(struct xe_device *xe) > } > > xe_display_flush_cleanup_work(xe); > + intel_encoder_block_all_hpds(display); > intel_dp_mst_suspend(display); > intel_hpd_cancel_work(display); > > @@ -471,6 +475,8 @@ void xe_display_pm_resume(struct xe_device *xe) > > intel_hpd_init(display); > > + intel_encoder_unblock_all_hpds(display); > + > if (has_display(xe)) { > intel_display_driver_resume(display); > drm_kms_helper_poll_enable(&xe->drm); -- Jani Nikula, Intel
