On 29.05.2023 10:47, Dmitry Baryshkov wrote: > On 29/05/2023 10:42, Konrad Dybcio wrote: >> >> >> On 29.05.2023 04:42, Dmitry Baryshkov wrote: >>> On Mon, 17 Apr 2023 at 18:30, Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> 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.. >>>> >>>> This series tries to address the lack of that. >>>> >>>> Example path: >>>> >>>> interconnects = <&bimc MASTER_AMPSS_M0 0 &config_noc SLAVE_DISPLAY_CFG 0>; >>> >>> If we are going to touch the MDSS interconnects, could you please also >>> add the rotator interconnect to the bindings? >>> We do not need to touch it at this time, but let's not have to change >>> bindings later again. >>> >> Ack > > Also, several points noted from the mdss fbdev driver: > > - All possible clents vote for the low bw setting. This includes DSI, HDMI, MDSS itself and INTF As in, "you need NUM_CLIENTS * MIN_VOTE" or as in "any client necessitates a vote"? > - SMMU also casts such vote, which I do not think should be necessary, unless there is a separate MDSS SMMU? There's one on 8996, pre-845 SoCs often have a MMSS MMU, 845 and later have a MMSS-specific TBU which (theoretically) requires a vote for access to 0x400-0x7ff SIDs > - PINGPONG cacsts high bw setting for the sake of speeding up the LUT tables if required. Hm, I think is would be a separate topic. Konrad >