I have been using the RM520N-GL modem for a project and have primarily operated it through the USB interface. I sent AT commands over the ttyUSB2 device node to control the device. However, as my project now requires using the PCI slot, I would like to seek guidance on how to migrate PCI Interface.
To provide more context, my Linux machine is ARM64-based and running on a Yocto image and supports PCI-EP mode.
From the AT command manual of the modem, I found a couple of commands that can be used to switch the modem to PCI mode, which are as follows:
AT+QCFG=“data_interface”,1,0 (to set the interface to PCI) AT+QCFG=“pcie/mode”,1 (set the PCI RC mode)
Are these commands sufficient to switch the modem from USB to PCIe mode? Additionally, I have the Quectel_Linux_PCIE_MHI_Driver_V1.3.7 driver, Could you please clarify the specific use case of this MHI driver for my Quectel modem in the PCIe configuration?
We tried the suggested configuration AT+QCFG=“PCIe/mode”,0, but nothing was listed on the lscpci command or in the kernel message.
I have the Quectel_Linux_PCIE_MHI_Driver_V1.3.7 driver, Could you please clarify the specific use case of this MHI driver for my Quectel modem in the PCIe configuration?
the host device is powered ON from the main supply, so when the host device gets the power, it means the modem will also get power from the PCI port, so we are thinking that during the PCI port scanning from PCI RC device, which is our host device, will scan the modem device, which is set as PCI EP device. How can we know that the boot timings are not matched between the device?
then how can we know that modem which is attached to PCI port, because we can only if device is attached or not, using “lspci” command.
Right now, we are not getting any device listed in “lspci” command in UNIX/LINUX system.
I have attached the snapshots of the dmesg for PCI and also shared the list of PCI devices using PCI devices. You can see in the “lspci” command that the PCI RC device, which is the MediaTek 510 Genio EVK kit, is showing a PCI bridge and a PCI-based Wi-Fi adapter, but it is not showing the Quectel modem, which is connected to the PCI slot.
A few more questions, related to AT commands, related to the configuration of the Quectel modem, we have used an ARM64 system to configure the Quectel modem. We have attached the Quectel modem to ARM64 device, used ttyUSB port to configure the AT command, which were,
AT+QCFG=“data_interface”,1,0 (to set the interface to PCI) AT+QCFG=“pcie/mode”,0 (set the PCI EP mode)
then save the user configuration, removed the Quectel modem from USB port, then attached the PCI port of the Quectel modem to PCI port of ARM64 device, and there was no listing of modem.
Is there any mistake in sequence that we are following?