CODEWITHSUNDEEP
macosfirmware
kent
kent

Reputation: 6566

EFI console on Mac OS X (Intel)

According to ADC documentation:

You can access Open Firmware this by holding down Command-Option-O-F at boot time.

However, in reality this does not work on current hardware. Does anybody know if there is a way (through trigger-keys, etc.) to get to an EFI console on contemporary-architecture (i.e., Intel) Macs?

EDIT: I am attempting to set up (and document) various Kernel Debug environments.

In experimenting with the boot-loading mechanisms of OS X, I have come to the following conclusion:

I had posted this question after encountering this 3rd case, which seems to occur on Core Duo (not Core 2 Duo!) machines: the result being that, once rEFIt is installed, the rEFIt menu DOES correctly get displayed at boot time, however is unusable because it receives no keyboard or mouse input (no USB drivers loaded?) and ultimately always ends up booting into the highest numbered boot partition.

Therefore, in scouring ADC documents and looking for a means to drop into a firmware/EFI console at boot-time, I came across the (somewhat outdated) statement from ADC [see above] and thought that it might be useful to ask on SO if anyone knew of an alternative.

Upvotes: 11

Views: 32066

Answers (4)

kent
kent

Reputation: 6566

The following quote comes from MacForensics.pdf

Apple does not offer any direct tools for accessing EFI. There is no key sequence available to enter EFI upon boot. There are, however, utilities available to access this. One such tool, rEFIt, is available on Sourceforge.net. The link at the time of this writing is http://refit.sourceforge.net/

Upvotes: 7

binarybob
binarybob

Reputation: 3569

As has already been pointed out, Intel Macs have EFI. However, booting from a CD with rEFIT installed (download the "6.5M ISO disk image", burn to disk using Disk Utility, then reboot holding down the 'C' key), you can select an option to Start EFI shell (its the leftmost icon on the bottom row on my Mac) which may be what you want?

Upvotes: 5

lothar
lothar

Reputation: 20219

Only Macs with PowerPC architecture have Open Firmware. The newer Intel based macs have EFI. As these firmwares are completely different their functionality is not equal.

AFAIK EFI does not have the corresponding feature of Open Firmware Access.

Upvotes: 8

pgb
pgb

Reputation: 25001

There is Refit (http://refit.sourceforge.net/) that is a "boot menu and maintenance toolkit", but I'm not sure if it covers the same functionality as the Open Firmware console.

Upvotes: 2

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