6.14-stable review patch. If anyone has any objections, please let me know.
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From: Marijn Suijten marijn.suijten@somainline.org
[ Upstream commit d245ce568929e30f650e260631f7ad14970d7c2c ]
When DSC is enabled the number of interfaces is forced to be 1, and documented that it is a "power-optimal" layout to use two DSC encoders together with two Layer Mixers. However, the same layout (two DSC hard-slice encoders with two LMs) is also used when the display is fed with data over two instead of one interface (common on 4k@120Hz smartphone panels with Dual-DSI). Solve this by simply removing the num_intf = 1 assignment as the count is already calculated by computing the number of physical encoders within the virtual encoder.
Fixes: 7e9cc175b159 ("drm/msm/disp/dpu1: Add support for DSC in topology") Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Reviewed-by: Jessica Zhang quic_jesszhan@quicinc.com Signed-off-by: Marijn Suijten marijn.suijten@somainline.org Patchwork: https://patchwork.freedesktop.org/patch/637649/ Link: https://lore.kernel.org/r/20250217-drm-msm-initial-dualpipe-dsc-fixes-v3-3-9... Signed-off-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c index 88591b6f9e350..e3555765eefb1 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c @@ -686,20 +686,21 @@ static struct msm_display_topology dpu_encoder_get_topology(
if (dsc) { /* - * Use 2 DSC encoders and 2 layer mixers per single interface + * Use 2 DSC encoders, 2 layer mixers and 1 or 2 interfaces * when Display Stream Compression (DSC) is enabled, * and when enough DSC blocks are available. * This is power-optimal and can drive up to (including) 4k * screens. */ - if (dpu_kms->catalog->dsc_count >= 2) { + WARN(topology.num_intf > 2, + "DSC topology cannot support more than 2 interfaces\n"); + if (intf_count >= 2 || dpu_kms->catalog->dsc_count >= 2) { topology.num_dsc = 2; topology.num_lm = 2; } else { topology.num_dsc = 1; topology.num_lm = 1; } - topology.num_intf = 1; }
return topology;