Can't access MIPI_CSI2 registers for IMX7 with linux 5.4

[stephenboy]

I am attempting to setup the MIPI_CSI2 registers on an IMX7DSABRESD dev board and I can't access the configuration registers via devmem2.  it works fine for other AIPS registers like 30330000, but not the MIPI set.

root@imx7dsabresd:~# ./devmem2 0x30330000

/dev/mem opened.

Memory mapped at address 0x30330000 0x76f7e000.

Value at address 0x30330000 (0x76f7e000) : 0x0

root@imx7dsavresd:~# .devmem2 0x30750000

/dev/mem opened.

At this point the shell hangs and needs to be rebooted.

I am running the latest 5.4 build: 5.4.24-2.1.0

What am I missing?

[igorpadykov]

Hi stephenboy

devmem2 is not supported by nxp, one can try memtool:

https://source.codeaurora.org/external/imx/imx-test/tree/test/memtool?h=imx_5.4.24_2.1.0

NXP linux documentation:

https://www.nxp.com/design/software/embedded-software/i-mx-software/embedded-linux-for-i-mx-applicat...

devmem2 was developed by community, issue may be posted on  meta-fsl-arm mailing list :

https://lists.yoctoproject.org/g/meta-freescale

Best regards
igor