questions of the clock frequecy of i.MX8-QXP

[killedByBugs]

I am using the i.MX8-qxp-c0 board. I would like to figure out what will be the clock frequency when I use PTP4l to do time synchronisation. It seems that clock frequency comes from the clock frequency of the NIC of the board.

I found that the AR8031 which is an ethernet chip is connected to a 25MHz clock. (from the clock diagram in file sch-29683_d7 of "i.MX 8QXP Design Files for the i.MX 8QXP MEK") Also, there is only one 25MHz crystal in the file BOM-29683_D5.xlsx. It's 405C35B25M00000.

Hence, I would like to make sure my information is correct:

1. the clock frequency of PTP4L used in i.MX8QXP is 25MHz

2. the clock source of the NIC in i.MX8QXP is 405C35B25M00000

Thank you in advance.

[Bio_TICFSL]

Hello,

clocks are described in sect. Clock Control Module (CCM) i.MX8MDQ Reference Manual
https://www.nxp.com/docs/en/reference-manual/IMX8MDQLQRM.pdf

in uboot sources one can look at

imx-common\arm\arch - uboot-imx - i.MX U-Boot 

in linux one needs to follow clock framework rules:
https://www.kernel.org/doc/Documentation/clk.txt 
https://elinux.org/images/b/b8/Elc2013_Clement.pdf 

clk-imx8mq.c\imx\clk\drivers - linux-imx - i.MX Linux kernel 

Regards