AT+QCFG="pcie_mbim" on RM520N-GL

I’m using an RM520N-GL modem with firmware version RM520NGLAAR03A03M4G. I have it running fine with MBIM over USB on a mainline linux 6.9.5 kernel, but I’m hoping to switch to use MBIM over MHI over PCIe using the mainline linux mhi_pci_generic, mhi_wwan_ctrl and mhi_wwan_mbim drivers.

Examining the AT+QCFG options, I noticed “pcie_mbim” which doesn’t seem to be documented.

Please could you clarify what the AT+QCFG=“pcie_mbim” setting shown in AT_QCFG=? does?

Should I be setting it to 1 as well as setting AT+QCFG=“data_interface”,1,0 if I’m intending to use MBIM over the PCIe interface?

It is set to 0 by default, and isn’t documented in the 2024-02-07 version of the AT Commands Manual nor in any of the release notes for the firmware.

Dear @arachsys
This AT command is used for test internally, please ignore this.
If you want to test PCIe, please configure data_interface, usbnet and install correct driver.

Thanks! I saw that I seemed to be able to bring up an PCIe MBIM session equally well with it set at 0 and 1 with the mainline kernel driver. I wonder if it might be sensible to add a note to the documentation to warn users that it is for internal debug purposes only?

Does the usbnet setting affect PCIe at all, or does that only affect the USB2/3 configuration? I assumed that PCIe presented all three types of endpoints unconditionally whereas USB can be configured to just one of the supported options?

Dear @arachsys
For internally AT command, we don’t have official document for it.
usbnet just can configure only one mode, and not affect PCIe.