Evgeny Zinoviev has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/38883 )
Change subject: mb/apple: Add iMac13,1 (21.5-inch, Late 2012) ......................................................................
Patch Set 1:
(1 comment)
https://review.coreboot.org/c/coreboot/+/38883/1//COMMIT_MSG Commit Message:
https://review.coreboot.org/c/coreboot/+/38883/1//COMMIT_MSG@31 PS1, Line 31: - Fan is pretending to be a leaf blower. Yes, it is a Delta fan. : - No support at all for the SMC. It probably controls the leaf blower. Actually you're right, it's controlled by SMC. But on my MacBooks it seems to be just working, living it's own life, increasing and decreasing speeds when needed. No idea what's wrong with your iMac.
Maybe there's some command for SMC to enable automatic speed adjustment? Or maybe we could search for any SMC commands, used in EFI, maybe we'll find something useful?
By the way, I wrote this https://review.coreboot.org/c/coreboot/+/33052 some time ago, I thought it will then help me to examine SMC and write some driver for it in future, but then it turned out that everything's fine on macbooks and I don't know what that driver would be needed for. But if it's necessary for iMac, well, perhaps we could turn that into a driver.