topic Re: devmem2 bus error on VF50 in Vybrid Processors

devmem2 bus error on VF50

tomaszciesla — Thu, 17 Mar 2022 07:16:21 GMT

hi is there a memtool for VFxxx F like for iMX?

https://community.nxp.com/t5/i-MX-Processors/devmem-return-bus-error/td-p/1033596

We want to access directly registers for tests. devmem2 works only with some of them:

root@col-vf50:~# devmem2 0x400481dc
/dev/mem opened.
Memory mapped at address 0x76f4a000.
Read at address 0x400481DC (0x76f4a1dc): 0x000022ED

root@col-vf50:~# devmem2 0x400d0024
/dev/mem opened.
Memory mapped at address 0x76f2f000.
Bus error

Re: devmem2 bus error on VF50

jamesbone — Mon, 21 Mar 2022 22:51:25 GMT

You can take a look to the following thread:

https://community.nxp.com/t5/Vybrid-Processors/VF5xx-Example-of-LPDDR2-Configuration/m-p/277982

Re: devmem2 bus error on VF50

tomaszciesla — Tue, 29 Mar 2022 16:28:38 GMT

error occurs when there's no clock enabled for the subsystem:

devmem2 0x4006b064 w 0x0000000f

unlocks read of Ethernet registers

   root@col-vf50:~# devmem2 0x400d0024
   /dev/mem opened.
   Memory mapped at address 0x76f93000.
   Read at address 0x400D0024 (0x76f93024): 0xF0000000