PCIe Drivers for Quectel RM500Q-AE

Hi, I am trying to configure my modem Quectel RM500Q-AE. I have installed the kmod-mhi-bus ( Kernel module for the Qualcomm MHI bus ) but still the :lspci is blank. What are the drivers that needs to be installed to configure it using modem manager.

What is your router model, are you sure it has PCI lines available on the M.2 connector?

My Router is Hilink HLK-7621A. yes it has pci.

You have no M.2 connector on the router, but it has PCI lines present on mPCIe connector, then you have some kind of mPCIe-M.2 adapter, right?
Do you have the proper adapter with PCI lines interconnected?

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Yes i do have mPCIe-M.2 connection. And I have enabled pci mode with AT commands, AT+QCFG="pcie/mode" -> +QCFG: "pcie/mode",0

Now I don not have access to AT commands anymore and have installed the MHI qualcomm driver, but it is still showing blank for lspci.

Could you share details about your adapter?

Even when you switch to PCI mode that will only move the data channel to PCI, GPS, diag and AT consoles are still exposed via USB

Yes, After configuring it as an PCIe endpoint (+QCFG: "pcie/mode",0 ), Still I can partially run AT commands through USB. and no device recognised at lspci. How should I proceed ?

For start try plugging in some other card to make sure PCIe even works

Tried that already with NVME SSD. Its recognised immediately.


00:01.0 PCI bridge: Device 0e8d:0801 (rev 01)
01:00.0 Non-Volatile memory controller: MAXIO Technology (Hangzhou) Ltd. NVMe SSD Controller MAP1202 (DRAM-less) (rev 01)

Then you either have a configuration problem on the modem or a FW issue since even without any driver to handle it would have showed up as a PCI device

I have already configured it has pcie EP mode.[ +QCFG: "pcie/mode",0 ]

Currently modem data_interface is
AT+QCFG="data_interface" //Query the current configuration.
+QCFG: "data_interface",0,0

So should i configure data interface to +QCFG: "data_interface",1,0   ??? i.e [ network port communication via PCIe interface, and
diagnostic port communication via USB interface. ]

And what else should i configure to make it recognize at lspci ?

Forget about the modem for a while, tell us about your adapter.

My mistake, Actually i do't have mPCIe-M.2. On my setup router pcie and usb 2.0 directly routed to M.2 Slot on my board, My modem is connected to this slot.

That sounds confusing to me... Any chance to see a picture?


Oh, I see... So it is not the HLK-7621a router, it is a custom board with HLK7621 module on it, both are shown here.
In this case you need to check that all the PCI lines (PETn0 PETp0 PERn0 PERp0 and REFCLK+/-) are connected between the HLK7621 module and M.2 connector.

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I think you should ask this question in a Quectel forum if you can't find the answer in the modem manual.

Not just because I want to be difficult.. This problem has nothing to do with OpenWrt. It's specific to your modem hardware and firmware. And Quectel will be the experts on that

Ok I will post this issue on Quectel forum. Could you list the appropriate driver packages that needed to be installed on OpenWRT. So i can configure this Modem ( Quectel RM500Q-AE ) with Modem manager protocol in future. Thanks.

Is there any reason not to install every driver pacage with "mhi" in the name, and see which ones you need/want?

But first you'll have to make the modem show up on a PCI bus. Driver installation is the next problem after that. I don't think skipping a step will work in this case.

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