PCIe probe failure on AmLogic A311D after 6.18-rc1

[Bjorn Helgaas]

[+cc Meson folks, Krishna, author of c96992a24bec]

On Thu, Oct 23, 2025 at 11:33:07AM +0000, Linnaea Lavia wrote:
> I'm getting the following in dmesg after installing 6.18-rc1 on a VIM3 board.
> 
> [    5.391324] [     T50] dw-pcie fc000000.pcie: error -ENXIO: IRQ index 1 not found
> [    5.411265] [     T50] meson-pcie fc000000.pcie: host bridge /soc/pcie at fc000000 ranges:
> [    5.415323] [     T50] meson-pcie fc000000.pcie:       IO 0x00fc600000..0x00fc6fffff -> 0x0000000000
> [    5.422278] [     T50] meson-pcie fc000000.pcie:      MEM 0x00fc700000..0x00fdffffff -> 0x00fc700000
> [    5.442280] [     T50] meson-pcie fc000000.pcie: error -EBUSY: can't request region for resource [mem 0xfc000000-0xfc3fffff]
> [    5.449631] [     T50] meson-pcie fc000000.pcie: Add PCIe port failed, -16
> [    5.458779] [     T50] meson-pcie fc000000.pcie: probe with driver meson-pcie failed with error -16
> 
> I think the problem is related to c96992a24bec("PCI: dwc: Add
> support for ELBI resource mapping") and 2f2cea1ea70a("PCI:
> dwc/meson: Rework PCI config and DW port logic register accesses"),
> as they're both trying to map ELBI/DBI registers.

Thanks for the report!  Can you post complete dmesg logs for working
and broken boots, e.g., v6.17 and v6.18-rc1?

#regzbot ^introduced: v6.18-rc1