Now I can reply my very own query, after seemingly having gone down one rabbit-hole and are available up by one other.
Because the dialog within the feedback on the query goes, it ought to most likely be potential to position iPXE in an Apple Disk Picture inside a NetBoot Picture and chainload into it utilizing BSDP. Nevertheless, as all the time, the satan is within the particulars and with my particular {hardware} (MacBookPro11,1; A1502 EMC 2678) this concept will not be possible to pursuit.
The weakest hyperlink is the wifi interface, the Broadcom bcm4360 with pci id 14e4:43a0. These playing cards will not be just like the bcm44xx collection. As a matter of truth, they don’t seem to be even corresponding to different bcm43xx playing cards. The one datasheet one can ever discover for them, at the least with out signing an NDA, is a skinny eight web page doc describing trivial issues akin to its bodily dimensions. Not like the equally named playing cards, nobody has revealed any open-source drivers. To one of the best of my understanding the wifi is virtually fully unusable with FreeBSD, illumos, NetBSD and OpenBSD. They solely work beneath Linux if loading binary blobs supplied by Broadcom (alpine, arch, debian, ubuntu). One can safely assume that iPXE is not going to implement drivers for a tool not one of the open-source working techniques help natively.
With no scarcity of voices believing info to be completely different, one of the best place to look is the precise supply codes. The PCI_DEVID_BCM4360_D11AC fixed will not be used wherever in FreeBSD, NetBSD fully lacks the anticipated PCI_PRODUCT_BROADCOM_BCM4360 fixed, and OpenBSD doesn’t point out the PCI_PRODUCT_BROADCOM_BCM4360 fixed when enumerating the record of supported gadgets.
Once I was given this laptop a fews days again, I believed one might run an open-source Darwin on it. It appears nevertheless that OpenDarwin was introduced lifeless in 2006, and PureDarwin misplaced traction round 2015. Even when there have been energetic communities, Apple would have been contractually prohibited to open-source their wifi-drivers, successfully making wifi-support macOS particular somewhat out there in Darwin¹.
Supposedly there are macbooks with different wifi chipsets. I am going to go away my very own reply unaccepted, hoping somebody will finally present a solution which truly provides a full resolution to the specified use-case for anybody with a supported card.
