Hello Wei Yang,
For details on the different iterations of the i.MX8M you can refer to the i.MX8M Fact Sheet (link below)
https://www.nxp.com/docs/en/fact-sheet/i.MX8M-FS.pdf
For the i.MX8MM please refer to the following Fact Sheet:
https://www.nxp.com/docs/en/fact-sheet/IMX8MMINIFS.pdf
As for the i.MX8QuadMax and i.MX8QuadX variants, I would need to ask you to please contact your FAE as these processors have not been released and there is no public technical information available yet.
My apologies for the inconvenience.
Regards,