#164 more macbook ports

go in coffee shop with librebooted macbook air running openbsd, but you look like any other citizen of starb**ks

libreboot by stealth

unorganised notes. i was looking at this bios update from apple for macbook air 4,2 (2011 sandybridge laptop that coreboot supports):

https://support.apple.com/kb/dl1497?locale=en_US

yeah and it's lzma compressed inside, everything is, you start extracting stuff and you eventually just get lots of files

see file paths below (on my system, after extracting), i found an ifd.bin and me.bin

so we could theoretically auto-download and auto-truncate like on thinkpads, in lbmk. and use apple's ifd, just tweak regions in ifdtool, and set massive CBFS size in coreboot (8MB minus 84KB. me_cleaner got the ME i found in apple's update down to 80KB, and plus the 4KB IFD - the IFD is gbe-less, so i guess there's no intel NIC)

i've ordered a macbook air 4,2 and i'll be testing it

ifd:
/home/leah/Downloads/mbair42/MacBookAir EFI Update/System/Library/CoreServices/Firmware Updates/MacBookAirEFIUpdate-2.4/MacVolume/1CEAD970.raw

ME:
/home/leah/Downloads/mbair42/MacBookAir EFI Update/System/Library/CoreServices/Firmware Updates/MacBookAirEFIUpdate-2.4/MacVolume/F1143A53.raw <-- looks sus
^ definitely sus. me_cleaner was able to process it



21:34 <nic3-14159[m]> leah: Not sure if you saw this before, but there are PRx settings, but configured improperly in a way that allows partial writes to the flash (not the whole bios region): https://github.com/gch1p/mmga#how-it-works


...
https://github.com/gch1p/mmga#how-it-works

more macbook ports
https://review.coreboot.org/c/coreboot/+/32604
https://review.coreboot.org/c/coreboot/+/33151
https://review.coreboot.org/c/coreboot/+/32673
https://ch1p.io/coreboot-mba52-flashing/
https://review.coreboot.org/q/macbook
https://ch1p.io/coreboot-macbook-support/
https://github.com/gch1p/mmga#how-it-works <-- macbook flash scripts

It's possible to flash externally!

 <leah> f_: it's possible to flash entirely from software, from apple efi to coreboot

ch1p is Evgeny on irc. author of the macbook ports linked to on gerrit

nic3-14159 is looking into patches he did aswell before ch1p came back after hiatus, to see if i'm missing anything in the links in the abve notes

nic mentioned something about macbook 8,1 on irc

WIP macbook air 4,2 port, not tested yet until the one i bought arrives at my lab:

https://browse.libreboot.org/lbmk.git/commit/?h=mbair42_wip_2&id=f0e5cf5dddd1fcd355ddf17060a0f1ad48e1cacf

also found this post

https://ch1p.io/coreboot-macbook-support/