mipi dsi in uboot

[Joe_C]

On the IMx8MQ platform, I used 'memtool' to read the setting values of miPI DSI registers in the kernel and set the MIpi DSI in Uboot with these values. Now The problem I encountered was that I could not get a DPHY Lock.Now I set the clock register according to the registers of the kernel, and the printed clocks are as follows: DSI Core CLK =266M, DSI PHY ref CLK =22M, DSI ESC RX CLK =39M.In addition, I modified it with the framework of \drivers\video\mipi_dsi_northwest.What should I do to debug the MIPI signal in IMx8MQ Uboot?

[igorpadykov]

Hi Joe_C

reason for not locking may be that mipi-dsi supports limited number of frequencies,

one can look at below suggestions:

https://community.nxp.com/t5/i-MX-Processors/Display-pixel-clock-limitation-to-74-25-MHz/m-p/914038

pay attention to pll reference clock MIPI_DSI_PHY_REF_CLK_ROOT described in Table 5-1. Clock Root Table

i.MX 8M Dual/8M QuadLite/8M Quad Applications Processors Reference Manual

compare it with linux :

https://source.codeaurora.org/external/imx/imx-test/tree/test/mxc_clock_test?h=imx_5.4.47_2.2.0

Best regards
igor