Re: [Freedreno] [PATCH 0/5] MDSS reg bus interconnect

From: Jeykumar Sankaran
Date: Wed Apr 19 2023 - 16:07:36 EST




On 4/17/2023 8:30 AM, Konrad Dybcio wrote:
Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
another path that needs to be handled to ensure MDSS functions properly,
namely the "reg bus", a.k.a the CPU-MDSS interconnect.

Gating that path may have a variety of effects.. from none to otherwise
inexplicable DSI timeouts..
Current DPU driver already votes on the "reg bus" indirectly through the display AHB clock handle[<&dispcc DISP_CC_MDSS_AHB_CLK>] in DTSI. Can you provide more details on the issues that warrants this patch series?

Thanks
Jeykumar S

This series tries to address the lack of that.

Example path:

interconnects = <&bimc MASTER_AMPSS_M0 0 &config_noc SLAVE_DISPLAY_CFG 0>;

Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
---
Konrad Dybcio (5):
dt-bindings: display/msm: Add reg bus interconnect
drm/msm/dpu1: Rename path references to mdp_path
drm/msm/mdss: Rename path references to mdp_path
drm/msm/mdss: Handle the reg bus ICC path
drm/msm/dpu1: Handle the reg bus ICC path

.../bindings/display/msm/mdss-common.yaml | 1 +
drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c | 10 +++----
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 34 ++++++++++++++++-----
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 5 ++--
drivers/gpu/drm/msm/msm_mdss.c | 35 ++++++++++++++--------
5 files changed, 57 insertions(+), 28 deletions(-)
---
base-commit: d3f2cd24819158bb70701c3549e586f9df9cee67
change-id: 20230417-topic-dpu_regbus-abc94a770952

Best regards,