Change in coreboot[master]: device/pci_device.c: Scan only one device for PCIe

[Shelley Chen (Code Review)]

Attention is currently required from: Hung-Te Lin, Furquan Shaikh, Jianjun Wang.
Shelley Chen has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56788 )

Change subject: device/pci_device.c: Scan only one device for PCIe
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Patch Set 2:

(1 comment)

Patchset:

PS2: 
Hi Hung-Te and Jianjun,

Sorry for the delay.  I've finally got an example of what is needed from partners.  Please see CL stack for example of how we want to organize the code.  The main bit of code that we need from Mediatek is the ATU mapping logic, which you have already implemented in the arch_pci_map_bus() function in CB:56790.

For reference, please take a look at the doc that Hung-Te pointed you to at in CB:57861
There is also a live patch train here: CB:58683
Anything prefixed with "DO NOT SUBMIT:" (CB:58668, CB:58683) are the changes that we are proposing the partner make to maximize code reuse.  I have left comments in each of these CLs to explain the reasoning behind each of the suggestions.

Please let me know if you have any questions after looking through these pointers.

Thanks!