The original CSC code is located in the file: /efs/imei/mps_code.dat

The current CSC code is located in the file /system/csc/language.xml

CSCs are located in the base directory: /system/csc under their own subdirectories.

So MM1 (CSC for M1) is located at /system/csc/MM1 and has these subdirectories and files

csc_contents/enforceskippingpackates.txt
system/csc/contents.db
system/csc/customer.xml
system/csc/others.xml
system/csc/sales_code.dat