Comment 5 for bug 1941854

@Andy,

In this case,

please refer something like:

$ lspci -nnv -d ::0x0302
01:00.0 3D controller [0302]: NVIDIA Corporation GP108M [GeForce MX150] [10de:1d10] (rev a1)
 Subsystem: Lenovo ThinkPad T480 [17aa:225e]
 Flags: bus master, fast devsel, latency 0, IRQ 169, IOMMU group 13
 Memory at dc000000 (32-bit, non-prefetchable) [size=16M]
 Memory at 80000000 (64-bit, prefetchable) [size=256M] # <----- here
 Memory at 90000000 (64-bit, prefetchable) [size=32M]
 I/O ports at d000 [size=128]
 Capabilities: <access denied>
 Kernel driver in use: nvidia
 Kernel modules: nouveau, nvidia_drm, nvidia

could you please help to confirm the memory here is same as you saw in BIOS?

When implementing the solution, please consider the multi GPU cases.

To filter out the iGPU, please refer ACPI spec and the following:

```
jeremysu@arch [ /home/jeremysu ]
$ cat /sys/bus/pci/devices/0000\:00\:02.0/firmware_node/adr
0x00020000
jeremysu@arch [ /home/jeremysu ]
$ cat /sys/bus/pci/devices/0000\:01\:00.0/firmware_node/adr
0x00000000
```

for GPU class, please consider all display classes (e.g. 0x0300, 0x0302, etc...)