We are trying to enable TSN on the Layerscape LS1028ARDB development board. We are running the following commands from the LS1028A BSP User Guide, Rev. 0.3, 04/2019.
4.2.13.4.2 Enable timestamp on switch
Follow the following commands to enable timestamp on switch:
#Init PTP:
devmem 0x1fc0900a0 w 0x00000004
#Get PTP real time(second):
devmem 0x1fc0900c4
When I run the first command to enable timestamping:
root@NXP-1:~# devmem 0x1fc0900a0 w 0x00000004
It results in the following error:
-bash: devmem: command not found
After finding this forum post, I installed devmem2 from us.ports.ubuntu.com and ran the following variation of the command, which uses devmem2 instead of devmem:
root@NXP-1:~# devmem2 0x1fc0900a0 w 0x00000004
This is successful:
/dev/mem opened.
Memory mapped at address 0xffffbd909000.
Value at address 0xFC0900A0 (0xffffbd909a0): 0x4
Written 0x4; readback 0x4
Then I run the next command from the User Guide, to see the PTP time:
root@NXP-1:~# devmem 0x1fc0900c4
This results in the following errror:
/dev/mem opened.
Memory mapped at address 0xffff8ea5d000.
Bus error
Questions:
What does this error mean?
How do I see the PTP time?
Is PTP timestamping going to work in the switch?
Where do I find documentation on these addresses?
When will there be corrected, tested, and verified version of the User Guide for the LS1028ARDB made available so I stop wasting so much time debugging the errors in the current User Guide?
Jeremy Impson
After booting up LS1028ARDB, the following commands could be executed successfully.
root@localhost:/test_dir_new# devmem 0x1fc0900a0 w 0x00000004
root@localhost:/test_dir_new# devmem 0x1fc0900c4
0x0000000C
You could use LSDK 19.09 release, init PTP is enabled in Linux Kernel by default.