I am trying to use a PI7C9X440SL PCIe/USB adapter on sdm845.
This PCIe device does not support MSI interrupts.
On 5.10 kernel, the pci device is detected but EHCI driver probe fails with this message “Found HC with no IRQ. Check BIOS/PCI”.
lspci shows that legacy interrupt cannot be found:
#lspci -vv -s 0000:03:00.2 0000:03:00.2 USB controller: Pericom Semiconductor PI7C9X442SL USB EHCI Controller (rev 01) (prog-if 20 [EHCI]) Subsystem: Pericom Semiconductor PI7C9X442SL USB EHCI Controller Control: I/O- Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Interrupt: pin C routed to IRQ 0 Region 0: Memory at 60302000 (32-bit, non-prefetchable) [size=256]
It is not clear to me if legacy interrupts are supported by the pcie-qcom driver.
Do I need to add the PCIe/USB device description in the device tree for this to work ?