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Did Yosemite Update Boot Firmware?
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Also please let us have output from the following command:
system_profiler SPHardwareDataType | grep ROM
I will have to run the commands again then and will get back to you in a few hours. I will post from output from the first command, and the second, and then I will reboot again and run the same process?
It may be unnecessary to re-run the bless command.
Installation of firmware may have succeeded during the waiting period that you described. Don't expect a successful installation to be followed by a message of confirmation.
I checked my system report and the version is still B14, wouldn't that have changed if the downgrade was truly completed?
So I run the commands w\o the bless command?
Here is the output for command 1:
/usr/sbin/bless -mount / -firmware ~/Desktop/MBPRetinaEFIUpdated-1.3/MBP111_0138_B03_LOCKED.scap --recovery --setBoot --nextonly --verbose
EFI found at IODeviceTree:/efi
GPT detected
No auxiliary booter partition required
System partition found
Preferred system partition found: disk0s1
Returning booter information dictionary:
<CFBasicHash 0x7fd84340a400 [0x7fff7f191f00]>{type = mutable dict, count = 3,
entries =>
0 : <CFString 0x109448e70 [0x7fff7f191f00]>{contents = "System Partitions"} = (
disk0s1
)
1 : <CFString 0x109449650 [0x7fff7f191f00]>{contents = "Data Partitions"} = (
disk0s2
)
2 : <CFString 0x109449670 [0x7fff7f191f00]>{contents = "Auxiliary Partitions"} = (
)
}
Substituting ESP disk0s1
Mounting at /Volumes/bless.knxy
Executing "/sbin/mount"
mount_msdos: /dev/disk0s1: Permission denied
Returned 18176
/sbin/mount returned non-0 exit status
Failed to determine auxiliary partition mountpoint for disk0s1
Error while writing firmware updater for EFI
--
edit:
i am logged into the only account on this mac (admin), folder is titled same as command line indicates and is located on desktop, filename for EFI update is also the same as indicated on command line.
Just to let you know
Do you want me to keep the bless?
----------
Here we go:
sudo /usr/sbin/bless -mount / -firmware ~/Desktop/update/MBP111_0138_B03_LOCKED.scap --recovery --setBoot --nextonly --verbose\
>
Password:
EFI found at IODeviceTree:/efi
GPT detected
No auxiliary booter partition required
System partition found
Preferred system partition found: disk0s1
Returning booter information dictionary:
<CFBasicHash 0x7fa6c3507330 [0x7fff7a18cf00]>{type = mutable dict, count = 3,
entries =>
0 : <CFString 0x10cd91e70 [0x7fff7a18cf00]>{contents = "System Partitions"} = (
disk0s1
)
1 : <CFString 0x10cd92650 [0x7fff7a18cf00]>{contents = "Data Partitions"} = (
disk0s2
)
2 : <CFString 0x10cd92670 [0x7fff7a18cf00]>{contents = "Auxiliary Partitions"} = (
)
}
Substituting ESP disk0s1
Mounting at /Volumes/bless.CS4i
Executing "/sbin/mount"
Returned 0
Deleting contents of EFI cache directory
Creating /Volumes/bless.CS4i/EFI/APPLE/FIRMWARE if needed
Deleting previous contents of /Volumes/bless.CS4i/EFI/APPLE/FIRMWARE
Deleting /Volumes/bless.CS4i/EFI/APPLE/FIRMWARE/MBP111_0138_B03_LOCKED.scap (8454768 bytes)
Opened dest at /Volumes/bless.CS4i/EFI/APPLE/FIRMWARE//MBP111_0138_B03_LOCKED.scap for writing
preallocation not supported on this filesystem for /Volumes/bless.CS4i/EFI/APPLE/FIRMWARE//MBP111_0138_B03_LOCKED.scap
/Volumes/bless.CS4i/EFI/APPLE/FIRMWARE//MBP111_0138_B03_LOCKED.scap created successfully
Relative path of /Volumes/bless.CS4i/EFI/APPLE/FIRMWARE//MBP111_0138_B03_LOCKED.scap is \EFI\APPLE\FIRMWARE\MBP111_0138_B03_LOCKED.scap
IOMedia disk0s1 has UUID 829A1425-C3CA-4F8D-8EB5-EE7E5D7399D0
Executing "/sbin/umount"
Returned 0
Write to RTC: 0
Setting EFI NVRAM:
<CFBasicHash 0x7fa6c3402da0 [0x7fff7a18cf00]>{type = mutable dict, count = 1,
entries =>
2 : <CFString 0x10cd91eb0 [0x7fff7a18cf00]>{contents = "efi-apple-recovery"} = <CFString 0x7fa6c3508a90 [0x7fff7a18cf00]>{contents = "<array><dict><key>IOMatch</key><dict><key>IOProviderClass</key><string>IOMedia</string><key>IOPropertyMatch</key><dict><key>UUID</key><string>829A1425-C3CA-4F8D-8EB5-EE7E5D7399D0</string></dict></dict><key>BLLastBSDName</key><string>disk0s1</string></dict><dict><key>IOEFIDevicePathType</key><string>MediaFilePath</string><key>Path</key><string>\EFI\APPLE\FIRMWARE\MBP111_0138_B03_LOCKED.scap</string></dict></array>"}
}
thats command 1,
command 2 is as follows:
clear ; diskutil mount /dev/disk0s1 ; ls -l /Volumes/EFI/EFI/APPLE/FIRMWARE/ ; diskutil unmount /dev/disk0s1
Volume EFI on /dev/disk0s1 mounted
total 16514
-rwxrwxrwx 1 Admin staff 8454768 Mar 31 23:34 MBP111_0138_B03_LOCKED.scap
Volume EFI on disk0s1 unmounted
then i restart.
Yesir, right after the second command was entered and finished. Rebooted with charger connected, and thats where it just takes like 1 minute to reboot
Is that shorter or longer than usual?
Try just the first command, then shutdown, then press and hold the power key for around five seconds; when the Mac bleeps, release the power key.
For reference only, http://pastebin.com/raw.php?i=Sx1GvQpw shows the routine that preceded reinstallation of firmware on my MacBookPro5,2.
A normal restart for me takes about 10 seconds. It takes 2 seconds to shutdown, get a black screen for about 1 second, then the initial black boot up screen followed by the gray loading screen - is another 5-7 seconds before im at the desktop.
Ok, so enter the first command only? Is there any need for the 2nd after the reboot
Not a reboot/restart.
From my previous post:
"… Try just the first command, then shutdown, then press and hold the power key for around five seconds; when the Mac bleeps, release the power key. …"
More specifically:
- the single-line command below (your earlier post showed something similar, but there was a trailing '\')
- a normal shut down
- an unusual start – the press and hold of the power button/key, until a bleep is heard.
Code:
sudo /usr/sbin/bless -mount / -firmware ~/Desktop/update/MBP111_0138_B03_LOCKED.scap --recovery --setBoot --nextonly --verboseBackground information
This 2009 quote is quite old, but relevant:
maflynn's memory is good. Older but still relevant, a 2006 topic: How to recover from firmware update failure?
Phrases such as 'firmware update failure' and 'most dangerous operation' are suitably alarming. Amongst the precautions that I suggested on 31st March, I'm particularly troubled by the apparently outdated manual page.
An additional precaution
To any reader of this topic:
- if you are not confident with command line executions (Terminal, single user mode, and so on), then a command line approach to preparation for a firmware update may be risky
(I have never handled a bricked Mac. Un-bricking would be beyond the scope of this topic.)
More optimistically
From a Google translation of the Russian article:
"… on Macs (unlike iOS, where there is a tyrant) Apple does not prohibit downgrade EFI. …"
With reference to the 2006 topic ("… Unfortunately … there was no firmware software to be installed …"), here's that other command:
Code:
clear ; diskutil mount /dev/disk0s1 ; ls -l /Volumes/EFI/EFI/APPLE/FIRMWARE/ ; diskutil unmount /dev/disk0s1That command:
- clears the screen
- uses diskutil to mount the volume at slice 1 of disk 0 (that is typically the EFI partition)
- lists the contents of the directory where we expect to find a copy of the file that the Mac will use for the firmware update
- uses diskutil to unmount the volume.
If the directory listing shows the appropriate .scap file then you should be assured that there is firmware to be installed.
Apple Support documentation
You might wonder why none of the following mention firmware:
- OS X: Keyboard shortcuts
- Startup key combinations for Intel-based Macs
- OS X Yosemite: Ways to start up your Mac
Performing a downgrade of firmware is an extraordinary routine; don't expect to find details in any current documentation from Apple.
----
Last but not least, from an archived Apple Support document, Desktop Macintosh: Hold power button to reset:
"… Follow these steps in the event that a firmware update is needed for these computers with no programmer's switch:
- After downloading and running the firmware update, shut down the computer.
- Wait until the computer is shut down and the power light is off.
- Press and hold the power button for several seconds.
- The computer will signal that a firmware update is ready to be installed by making a steady tone and the power button light will quickly flash several times for several seconds."
With more modern Macs I should not expect flashing lights and so on, but the routine is essentially similar:
- prepare for the update
- shut down
- start the Mac in a way that uses the prepared file.
Here's my sad story on failed downgrade of EFI Boot ROM firmware on 15-inch MacBook Pro with Retina display (rMBP) running OS X 10.9.5 (Mavericks). Probably someone is luckier than me and can help me out?