IMX8MM Dart, M4 Core /dev/ttyRPMSG missing

mariusoctavian — Tue, 14 Jan 2025 23:45:20 GMT

I have seen another posts but my case is different.

I compiled the SDK_2_16_000_EVK-MIMX8MM/boards/evkmimx8mm/multicore_examples/rpmsg_lite_str_echo_rtos

Memory region Used Size Region Size %age Used m_interrupts: 576 B 576 B 100.00% m_text: 15372 B 130496 B 11.78% m_data: 44112 B 128 KB 33.65% m_data2: 0 GB 16 MB 0.00% [100%] Built target rpmsg_lite_str_echo_rtos_imxcm4.elf

I am running linux Yocto kirkstone and the drivers are not loaded a boot and they are:

root@imx8mm:/lib/modules/5.15.60-imx8mm/kernel/drivers/rpmsg# ll total 56 drwxr-xr-x 2 root root 1024 Mar 9 2018 . drwxr-xr-x 11 root root 1024 Mar 9 2018 .. -rwxr-xr-x 1 root root 7240 Mar 9 2018 imx_rpmsg_pingpong.ko -rwxr-xr-x 1 root root 12064 Mar 9 2018 imx_rpmsg_tty.ko -rwxr-xr-x 1 root root 21208 Mar 9 2018 rpmsg_char.ko -rwxr-xr-x 1 root root 12352 Mar 9 2018 rpmsg_ctrl.ko

I boot linux and copy the elf as:

cp rpmsg_lite_str_echo_rtos_imxcm4.elf /lib/firmware echo stop > /sys/class/remoteproc/remoteproc0/state cat /sys/class/remoteproc/remoteproc0/state # stopped echo -n rpmsg_lite_str_echo_rtos_imxcm4.elf > /sys/class/remoteproc/remoteproc0/firmware cat /sys/class/remoteproc/remoteproc0/state # stopped echo start > /sys/class/remoteproc/remoteproc0/state cat /sys/class/remoteproc/remoteproc0/state # running modprobe imx_rpmsg_tty cat /sys/class/remoteproc/remoteproc0/state # running

UART 4 prints

RPMSG String Echo FreeRTOS RTOS API Demo..

lsmod shows

Module Size Used by imx_rpmsg_tty 16384 0 rpmsg_ctrl 16384 0 rpmsg_char 16384 1 rpmsg_ctrl

dmesg shows

[ 148.592651] virtio_rpmsg_bus virtio0: rpmsg host is online [ 148.592748] remoteproc0#vdev0buffer: registered virtio0 (type 7) [ 148.592759] remoteproc remoteproc0: remote processor imx-rproc is now up

dev folder has no /ttyR* device

Though the sys/class/remoteproc/remoteproc0 has quite few files

From the point LINUX->M4 everything looks okay in the sys but there is no /dev/ driver.

Any ideas what is wrong.
Thank you

Re: IMX8MM Dart, M4 Core /dev/ttyRPMSG missing

mariusoctavian — Wed, 15 Jan 2025 01:00:28 GMT

The M4 is stuck in:

rpmsg_lite_wait_for_link_up(my_rpmsg, RL_BLOCK);

Any ideas ?

NXP Designs中的主题 Re: IMX8MM Dart, M4 Core /dev/ttyRPMSG missing

IMX8MM Dart, M4 Core /dev/ttyRPMSG missing

Re: IMX8MM Dart, M4 Core /dev/ttyRPMSG missing