[coreboot] Can not have IRQ from ethernet device connected to the PCIe #4 in legacy mode

[benoit]

Hi all,

I am facing a legacy IRQ under OS.
I am currently using Coreboot + FSP on baytrail.
My OS is running with IRQ in legacy using PIRQ described in
coreboot/src/mainboard/intel/bayleybay_fsp/irqroute.h .
Under the OS USB, SATA, SMBus are working well using legacy interrupt.
Nevertheless I have an ethernet device connected on the PCIe root #4 and
no IRQs are received.

I tried to change the IRQ in the interrupt line register without success.

I can compare also with a Phoenix BIOS, and with the same OS binary the
ethernet is working.

I check out also the ilb registers + 0x4d0 and 0x4d1 registers (ECL).
Everything is correctly initalized.

Do I need to activate/deactivate something in the PCIe root #4 to
forward legacy interrupt to the 8259 PIC ?

Many thanks in advance
Benoit