On Sun, Sep 13, 2026 at 11:38:43PM +0000, [email protected] wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s)
> to consider:
> - [High] Missing `flush_hw_mask` update when converting to legacy LM cursor
> breaks cursor updates.
> --
>
> commit e1dbf3d7b78aa6bf44fff588ff9b069eceea7f6b
> Author: Dmitry Baryshkov <[email protected]>
>
> drm/msm/mdp5: drop cursor pipe for msm8x76
>
> This commit removes the separate cursor plane configuration for MSM8976/56
> platforms. It drops the erroneously added pipe configuration to let the LM
> block provide a legacy cursor instead.
>
> > diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c
> > b/drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c
> > index 7c91fc1915f39..389d74ff75163 100644
> > --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c
> > +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_cfg.c
> > @@ -698,15 +698,6 @@ static const struct mdp5_cfg_hw msm8x76_config = {
> > MDP_PIPE_CAP_SW_PIX_EXT |
> > 0,
> > },
> > - .pipe_cursor = {
> > - .count = 1,
> > - .base = { 0x440DC },
> > - .caps = MDP_PIPE_CAP_HFLIP |
> > - MDP_PIPE_CAP_VFLIP |
> > - MDP_PIPE_CAP_SW_PIX_EXT |
> > - MDP_PIPE_CAP_CURSOR |
> > - 0,
> > - },
>
> [Severity: High]
> Since this drops the cursor pipe to rely on the legacy LM cursor, does the
> ctl.flush_hw_mask in msm8x76_config also need to be updated?
>
> Currently, flush_hw_mask is set to 0xffffffff for this platform. When
> standalone cursor updates use MDP5_CTL_FLUSH_CURSOR_0, fix_sw_flush() in
> mdp5_ctl.c translates this to an LM flush for legacy cursors. However, this
> fallback is only triggered if BIT_NEEDS_SW_FIX() determines the cursor flush
> bit is excluded from the platform's flush_hw_mask.
>
> Because the cursor bit is still included in the 0xffffffff mask, the
> software fix evaluates to false. This prevents the LM from being flushed
> and sends a hardware flush for a non-existent cursor block, which can
> cause the cursor to lag or freeze during standalone updates.
>
> Should flush_hw_mask be updated to exclude the cursor flush bits (for
> example, 0xffffffff & ~MDP5_CTL_FLUSH_CURSOR_0)?
This should not be necessary. The legacy cursor implemented in LM
doesn't update the HW mask.
>
> > .lm = {
> > .count = 2,
> > .base = { 0x44000, 0x45000 },
>
> --
> Sashiko AI review ยท
> https://sashiko.dev/#/patchset/[email protected]?part=1
--
With best wishes
Dmitry
