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The > > previous configuration violated the timing requirement stated in the > > i.MX8MQ Reference Manual: > > > > "The frequency of clk must be exactly equal to or greater than the RX > > byte clock coming from the RX DPHY." > > > > Update the clock configuration to ensure that the CSI core clock rate is > > equal to or greater than the incoming DPHY byte clock. The updated clock > > ratios are consistent with those used in NXP's downstream BSP. > > I believe this is a misreading of the docs. > > IMX8MQ_CLK_CSIX_PHY_REF refers to the UI pixel clock (clk_ui), not the RX DPHY > byte clock. All this change would do is to break streaming with more than 100 > Mpixels per second / 1064 Mbps per MIPI lane. > > As mentioned in the reference manual: > > "The frequency of clk_ui must be such that the data received on the data_out > output is greater than or equal to the total bandwidth of the physical MIPI > interface. Clk_ui has no relationship requirement with regards to ‘clk’ other > than the bandwidth requirement mentioned previously." > You are right — thank you for the detailed clarification. Given this, the commit message and the rationale behind this change are incorrect, and the current patch could indeed break higher-bandwidth streaming use cases. Thank you for catching this. I will revisit the clock assumptions and drop or rework this change based strictly on the documented bandwidth requirements in the next revision. Regards, Robby [...]