Analyzing PCIe enumeration in u-boot or linux using qemu, is it possible?

[Chan Kim]

Hello all,

I thought I would try to analyze u-boot's PCIe enumeration using qemu.
I used qemu-6.2 (old now) and built it for arm-softmmu. And I built
u-boot-v2022.07 using qemu_arm_defconfig and built linux-5.15.68 using
integrator_defconfig(just because I saw CONFIG_PCI=y). The linux image
doesn' matter much because I'm only interested in u-boot now.(but if I can
analyze linux too, it will be fantastic).

I could break at u-boot's pci_init function (called inside board_init_r
function, pci_init is one member function of init_sequence_r array) but it
seemed it doesn't do anything interesting. And then I found this text is
qemu-6.2.0's document (pcie.txt).

"Note that the PCIe features are available only when using the 'q35'
machine type on x86 architecture and the 'virt' machine type on AArch64.
Other machine types do not use PCIe at this time."

Then, does this mean I cannot attach a PCIe device model in qemu and debug
PCIe related S/W operation?
Can I do it with higher version of qemu?
Thank you!

Chan Kim