simplex
any ideas regarding my prev post?
You need to build UMR (I wonder if it's possible to install this application through your distribution's package manager and avoid building it manually). Detailed instructions are available here: https://gitlab.freedesktop.org/tomstdenis/umr/-/tree/main. The output will be a command-line utility. Then you should refer to the documentation for command formats.
Sorry, I can't be very helpful here, as I don't have much free time right now. I quickly skimmed through the documentation and might be mistaken in some areas, but in any case, this will provide a starting point for further investigation.
Reading the value of the register:
umr -r 0x1841
Writing the value of the register:
umr -w 0x1841 <new_value>
But, it seems, you can refer to registers by their names instead of addresses (this is preferable). Try combining the register name and fields in the read/write commands (instead of the address).
But how to set FMT_TRUNCATE_EN value if it has 0 0
As I understand, these are bit addresses. In this case, you need to change the zero bit (the rightmost bit in the binary value). To do this, you need to read the data from the register. Most likely, the output will be in hexadecimal form. If that's the case, then convert it to binary; clear the zero bit and convert it back to hexadecimal format; write the resulting number back to the register.