On Thu, 07 May 2026, James Xiong <[email protected]> wrote: > During driver probe, DMC firmware is loaded asynchronously via a > workqueue. There is a race between parse_dmc_fw() setting the payload > pointer (making has_dmc_id_fw() return true) and intel_dmc_load_program() > writing the firmware to hardware registers. If the probe thread calls > intel_dmc_enable_pipe() -> assert_dmc_loaded() in this window via > intel_modeset_setup_hw_state(), it sees parsed payload but stale HW > registers, triggering a ~20% intermittent WARNING on ADL-N warm boot.
I wonder if intel_dmc_enable_pipe() should call intel_dmc_wait_fw_load() itself? > > v2: Fix by calling intel_dmc_wait_fw_load() in > intel_modeset_setup_hw_state() before iterating the CRTCs (Gustavo > Sousa). > > Signed-off-by: James Xiong <[email protected]> > --- > drivers/gpu/drm/i915/display/intel_modeset_setup.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_modeset_setup.c > b/drivers/gpu/drm/i915/display/intel_modeset_setup.c > index e88082c8caac..277e56848470 100644 > --- a/drivers/gpu/drm/i915/display/intel_modeset_setup.c > +++ b/drivers/gpu/drm/i915/display/intel_modeset_setup.c > @@ -961,6 +961,8 @@ void intel_modeset_setup_hw_state(struct intel_display > *display, > * intel_sanitize_plane_mapping() may need to do vblank > * waits, so we need vblank interrupts restored beforehand. > */ > + intel_dmc_wait_fw_load(display); > + No matter what, the comment above now appears to refer to this intel_dmc_wait_fw_load() call, which makes no sense at all. BR, Jani. > for_each_intel_crtc(display->drm, crtc) { > struct intel_crtc_state *crtc_state = > to_intel_crtc_state(crtc->base.state); -- Jani Nikula, Intel
