On 3/17/26 4:30 PM, Dmitry Baryshkov wrote:
> Current topology code will try using 2 LMs with just one DSC, which
> breaks cases like SC7280 / Fairphone5.
(why/how?)
Konrad
> Forbid using 2 LMs split in such
> a case.
>
> Fixes: 1ce69c265a53 ("drm/msm/dpu: move resource allocation to CRTC")
> Reported-by: Luca Weiss <[email protected]>
> Closes: https://lore.kernel.org/r/[email protected]/
> Tested-by: Luca Weiss <[email protected]> # qcm6490-fairphone-fp5
> Signed-off-by: Dmitry Baryshkov <[email protected]>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index 6bf7c46379ae..96b67ea3fb4c 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -1410,7 +1410,8 @@ static struct msm_display_topology
> dpu_crtc_get_topology(
> topology.num_lm = 2;
> else if (topology.num_dsc == 2)
> topology.num_lm = 2;
> - else if (dpu_kms->catalog->caps->has_3d_merge)
> + else if (dpu_kms->catalog->caps->has_3d_merge &&
> + topology.num_dsc == 0)
> topology.num_lm = (mode->hdisplay > MAX_HDISPLAY_SPLIT) ? 2 : 1;
> else
> topology.num_lm = 1;
>
> ---
> base-commit: 50c4a49f7292b33b454ea1a16c4f77d6965405dc
> change-id: 20260317-fix-3d-dsc-4b073977ea19
>
> Best regards,
