On Wed, Jan 08, 2025 at 05:19:40PM -0800, Abhinav Kumar wrote:
>
>
> On 12/21/2024 9:00 PM, Dmitry Baryshkov wrote:
> > The driver isn't supposed to consult crtc_state->active/active_check for
> > resource allocation. Instead all resources should be allocated if
> > crtc_state->enabled is set. Stop consulting active / active_changed in
> > order to determine whether the hardware resources should be
> > (re)allocated.
> >
> > Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
> > Reported-by: Simona Vetter <simona.vetter@xxxxxxxx>
> > Closes: https://lore.kernel.org/dri-devel/ZtW_S0j5AEr4g0QW@phenom.ffwll.local/
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
> > ---
> > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 4 ----
> > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 3 +--
> > 2 files changed, 1 insertion(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > index 7191b1a6d41b3a96f956d199398f12b2923e8c82..65e33eba61726929b740831c95330756b2817e28 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > @@ -1264,10 +1264,6 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
> > DRM_DEBUG_ATOMIC("%s: check\n", dpu_crtc->name);
> > - /* force a full mode set if active state changed */
> > - if (crtc_state->active_changed)
> > - crtc_state->mode_changed = true;
> > -
> > if (cstate->num_mixers) {
> > rc = _dpu_crtc_check_and_setup_lm_bounds(crtc, crtc_state);
> > if (rc)
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > index 83de7564e2c1fe14fcf8c4f82335cafc937e1b99..d1ccdca6044353f110bf5b507788efe368f223a3 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > @@ -793,12 +793,11 @@ static int dpu_encoder_virt_atomic_check(
> > crtc_state->mode_changed = true;
> > /*
> > * Release and Allocate resources on every modeset
> > - * Dont allocate when active is false.
> > */
> > if (drm_atomic_crtc_needs_modeset(crtc_state)) {
> > dpu_rm_release(global_state, drm_enc);
> > - if (!crtc_state->active_changed || crtc_state->enable)
>
> I think this was leftover code.
>
> What happened was, we used to have dpu_rm_reserve() both in dpu_encoder's
> atomic_check and mode_set. Hence this is checking !active_changed because
> that case was expected to get handled in mode_set to avoid duplicate
> dpu_rm_reserve() calls. Code has progressed since then to drop the
> dpu_rm_reserve() from mode_set and only use atomic_check.
>
> So the correct fixes tag for this should be:
>
> Fixes: de3916c70a24 ("drm/msm/dpu: Track resources in global state")
Actually it should be:
Fixes: ccc862b957c6 ("drm/msm/dpu: Fix reservation failures in modeset")
> With that addressed, this is
>
> Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
>
> > + if (crtc_state->enable)
> > ret = dpu_rm_reserve(&dpu_kms->rm, global_state,
> > drm_enc, crtc_state, topology);
> > if (!ret)
> >
--
With best wishes
Dmitry
