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MP 1,1-5,1 MacPro5,1: BootROM thread | 144.0.0.0.0
- Thread starter tsialex
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Damned annoying that I can boot into Win10 and get the boot screen/Windows logo almost straight after boot, but can't get the same from Apple. Just impatient and venting. I go and take my anger out constructively by playing some Tomb Raider.
I have a Mac Pro 2010. I would like to boot with 970Evo NVMe, mounted on a PCIe card. I understand that with the new Boot Rom Apple version 140.0.0.0, HD NVMe have become bootable.
On my computer I installed Mojave and the version of the Rom is 138.0.0.0. How can I update the Rom?
If something does not work, is it possible to go back?
On my computer I installed Mojave and the version of the Rom is 138.0.0.0. How can I update the Rom?
If something does not work, is it possible to go back?
Read the first post #1
If you do a BootROM dump with ROMTool, yes, you can go back. If not, no.
Read the thread, every question that you can have is already answered multiple times.
Someone asked me for examples of corrupted NVRAM volumes. I can't publish the dump, NVRAM has some personal data like full name and iCloud account, but I can show a screenshot.
This one is from a early-2009 Mac Pro that got incapable of booting after MP51.0087.B00, one of the six that we now that corrupted just after MP51.0087.B00 was released.
This is the screenshot of the hardware IDs "file/part" of the already corrected BootROM:
Look at the order of things:
This is a example of one that still has all the hardware IDs, some corrupted ones are missing some or have none. I'll show more later, then I'll compile all into a new post.
This one is from a early-2009 Mac Pro that got incapable of booting after MP51.0087.B00, one of the six that we now that corrupted just after MP51.0087.B00 was released.
This is the screenshot of the hardware IDs "file/part" of the already corrected BootROM:
Look at the order of things:
- Fsys is the beginning,
- overridess followed by the bzip2 compressed descriptor, what I call the compressed blob,
- override version Base_xx (the descriptor version) [updated to Base_21],
- ssn followed by the System Serial Number (highlighted with black to hidden it),
- hwc followed by the Hardware Code (3 last digits of the SSN until 2012, for digits from 2012 on),
- son followed by the System/Sales Order Number (variable sizes, some times numbers, sometimes alphanumerical),
- EOF is the end (but it's not the end to calculate the checksum),
- highlighted in purple it's the checksum CRC32 big-endian (from Fsys to the last byte before the checksum), it's a fixed position.
- highlighted with yellow the hardware IDs wrongly positioned, ssn with black to hide it,
- highlighted with green are overridess followed by the BZip2 compressed descriptor,
- highlighted in purple it's the checksum and was incorrect.
This is a example of one that still has all the hardware IDs, some corrupted ones are missing some or have none. I'll show more later, then I'll compile all into a new post.
Last edited:
Interesting. Do the changed characters before _Ä`0q mean something and are they part of the BZip2 compressed descriptor?
The compressed blob starts with BZh1, it's the header of the stream, this is the decompressed blob:
Code:
ADD_DEVICE () [class="USBPort",location="top-front",speed="480",uhci-id="0x5d100000",ehci-id="0xfd500000"]
ADD_DEVICE () [class="USBPort",location="bottom-front",speed="480",uhci-id="0x3a200000",ehci-id="0xfa400000"]
ADD_DEVICE () [class="USBPort",location="right-rear",speed="480",uhci-id="0x3d100000",ehci-id="0xfd300000"]
ADD_DEVICE () [class="USBPort",location="center-rear",speed="480",uhci-id="0x1a200000",ehci-id="0xfa200000"]
ADD_DEVICE () [class="USBPort",location="left-rear",speed="480",uhci-id="0x1d100000",ehci-id="0xfd100000"]
ADD_DEVICE () [class="FireWirePort",location="rear-right",max-speed="800",port-id="0x01",phy-id="0x00"]
ADD_DEVICE () [class="FireWirePort",location="rear-left",max-speed="800",port-id="0x02",phy-id="0x00"]
ADD_DEVICE () [class="FireWirePort",location="front-top",max-speed="800",port-id="0x01",phy-id="0x01"]
ADD_DEVICE () [class="FireWirePort",location="front-bottom",max-speed="800",port-id="0x02",phy-id="0x01"]
SET_PROPERTY (class="Processor") [max-prochots="10000",ptype="iCore7"]
SET_PROPERTY (class="Sensor"&location="ICAC") [low-limit="0.1",high-limit="140",type="Current",description="CPU A, Core Low Side (Vcore) Current"]
SET_PROPERTY (class="Sensor"&location="ICBC") [low-limit="0.1",high-limit="140",type="Current",description="CPU B, Core Low Side (Vcore) Current"]
SET_PROPERTY (class="Sensor"&location="Ie1S") [low-limit="0",high-limit="18",type="Current",description="PCIe Slot 1, 12V Current"]
SET_PROPERTY (class="Sensor"&location="Ie2S") [low-limit="0",high-limit="18",type="Current",description="PCIe Slot 2, 12V Current"]
SET_PROPERTY (class="Sensor"&location="Ie3S") [low-limit="0",high-limit="18",type="Current",description="PCIe Slot 3, 12V Current"]
SET_PROPERTY (class="Sensor"&location="Ie4S") [low-limit="0",high-limit="18",type="Current",description="PCIe Slot 4, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IeAS") [low-limit="0",high-limit="18",type="Current",description="PCIe BoostA, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IeBS") [low-limit="0",high-limit="18",type="Current",description="PCIe BoostB, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IH1Z") [low-limit="0",high-limit="2",type="Current",description="HDD1, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IH2Z") [low-limit="0",high-limit="2",type="Current",description="HDD2, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IH3Z") [low-limit="0",high-limit="2",type="Current",description="HDD3, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IH4Z") [low-limit="0",high-limit="2",type="Current",description="HDD4, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IO0Z") [low-limit="0",high-limit="3",type="Current",description="ODD, 12V Current"]
SET_PROPERTY (class="Sensor"&location="IH5Z") [low-limit="0",high-limit="12",type="Current",description="HDD+ODD, 5V Current"]
SET_PROPERTY (class="Sensor"&location="IMAS") [low-limit="0.1",high-limit="50",type="Current",description="DIMM, PP1V5_S3_MEMA Current"]
SET_PROPERTY (class="Sensor"&location="IMBS") [low-limit="0.1",high-limit="50",type="Current",description="DIMM, PP1V5_S3_MEMB Current"]
SET_PROPERTY (class="Sensor"&location="IN0C") [low-limit="1",high-limit="40",type="Current",description="IOH Core, PP1V1_S0_IOH Northbridge Current"]
SET_PROPERTY (class="Sensor"&location="Ip0C") [low-limit="1",high-limit="80",type="Current",description="PSU, 12V Current (PSMI)"]
SET_PROPERTY (class="Sensor"&location="ICAB") [low-limit="0.1",high-limit="40",type="Current",description="PVTT, CPUA Current"]
SET_PROPERTY (class="Sensor"&location="ICBB") [low-limit="0.1",high-limit="40",type="Current",description="PVTT, CPUB Current"]
SET_PROPERTY (class="Sensor"&location="IS1C") [low-limit="0.25",high-limit="5.0",type="Current",description="PP1V05_S0_SB Current"]
SET_PROPERTY (class="Sensor"&location="IS2C") [low-limit="0.25",high-limit="2.3",type="Current",description="PP1V5_S0_SB Current"]
SET_PROPERTY (class="Sensor"&location="Ip1M") [low-limit="0.5",high-limit="18",type="Current",description="PP12V_S0 CPUA 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip2M") [low-limit="0",high-limit="18",type="Current",description="PP12V_S0 CPUB 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip3M") [low-limit="0.5",high-limit="18",type="Current",description="PP12V_S0 MEMA 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip4M") [low-limit="0",high-limit="18",type="Current",description="PP12V_S0 MEMB 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip5M") [low-limit="1",high-limit="18",type="Current",description="PP12V_S0 MLB1 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip6M") [low-limit="1",high-limit="18",type="Current",description="PP12V_S0 MLB2 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip7M") [low-limit="0",high-limit="18",type="Current",description="PP12V_S0 PCIE1 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="Ip8M") [low-limit="0",high-limit="18",type="Current",description="PP12V_S0 PCIE2 240VA Main Current"]
SET_PROPERTY (class="Sensor"&location="TA0P") [low-limit="5",high-limit="45",type="Temperature",description="System Ambient Temperature"]
SET_PROPERTY (class="Sensor"&location="TCAC") [low-limit="1",high-limit="85",type="Temperature",description="CPU A, Core 0 Relative Temperature to ProcHot (PECI)"]
SET_PROPERTY (class="Sensor"&location="TCAD") [low-limit="5",high-limit="95",type="Temperature",description="Temperature, CPU A Tdiode"]
SET_PROPERTY (class="Sensor"&location="TCBC") [low-limit="1",high-limit="85",type="Temperature",description="CPU B, Core 0 Relative Temperature to ProcHot (PECI)"]
SET_PROPERTY (class="Sensor"&location="TCBD") [low-limit="5",high-limit="95",type="Temperature",description="Temperature, CPU B Tdiode"]
SET_PROPERTY (class="Sensor"&location="TCAH") [low-limit="5",high-limit="85",type="Temperature",description="CPU A, HeatSink Temperature"]
SET_PROPERTY (class="Sensor"&location="TCBH") [low-limit="5",high-limit="85",type="Temperature",description="CPU B, HeatSink Temperature"]
SET_PROPERTY (class="Sensor"&location="TH1P") [low-limit="5",high-limit="50",type="Temperature",description="Drive Bay 1, HDD Temperature (On Drive Carrier)"]
SET_PROPERTY (class="Sensor"&location="TH2P") [low-limit="5",high-limit="50",type="Temperature",description="Drive Bay 2, HDD Temperature (On Drive Carrier)"]
SET_PROPERTY (class="Sensor"&location="TH3P") [low-limit="5",high-limit="50",type="Temperature",description="Drive Bay 3, HDD Temperature (On Drive Carrier)"]
SET_PROPERTY (class="Sensor"&location="TH4P") [low-limit="5",high-limit="50",type="Temperature",description="Drive Bay 4, HDD Temperature (On Drive Carrier)"]
SET_PROPERTY (class="Sensor"&location="TM1P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 1 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM2P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 2 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM3P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 3 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM4P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 4 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM5P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 5 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM6P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 6 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM7P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 7 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TM8P") [low-limit="5",high-limit="80",type="Temperature",description="DIMM Proximity 8 Temperature (On Riser)"]
SET_PROPERTY (class="Sensor"&location="TMA1") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUA, SLOT1, CHA - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMA2") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUA, SLOT2, CHB - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMA3") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUA, SLOT3, CHC - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMA4") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUA, SLOT4, CHC - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMB1") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUB, SLOT5, CHA - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMB2") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUB, SLOT6, CHB - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMB3") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUB, SLOT7, CHC - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TMB4") [low-limit="5",high-limit="80",type="Temperature",description="DIMM, CPUB, SLOT8, CHC - SPD Temperature"]
SET_PROPERTY (class="Sensor"&location="TN0D") [low-limit="5",high-limit="95",type="Temperature",description="Temperature, IOH Tdiode"]
SET_PROPERTY (class="Sensor"&location="TN0H") [low-limit="5",high-limit="75",type="Temperature",description="IOH, HeatSink Temperature"]
SET_PROPERTY (class="Sensor"&location="Tp0C") [low-limit="5",high-limit="100",type="Temperature",description="PS, AC/DC Supply Temperature 1"]
SET_PROPERTY (class="Sensor"&location="Tp1C") [low-limit="5",high-limit="100",type="Temperature",description="PS, AC/DC Supply Temperature 2"]
SET_PROPERTY (class="Sensor"&location="Te1S") [low-limit="5",high-limit="95",type="Temperature",description="PCIE slot 1 Temperature"]
SET_PROPERTY (class="Sensor"&location="Te2S") [low-limit="5",high-limit="95",type="Temperature",description="PCIE slot 2 Temperature"]
SET_PROPERTY (class="Sensor"&location="Te3S") [low-limit="5",high-limit="95",type="Temperature",description="PCIE slot 3 Temperature"]
SET_PROPERTY (class="Sensor"&location="Te4S") [low-limit="5",high-limit="95",type="Temperature",description="PCIE slot 4 Temperature"]
SET_PROPERTY (class="Sensor"&location="Te5S") [low-limit="5",high-limit="95",type="Temperature",description="PCIE RAID card Temperature"]
SET_PROPERTY (class="Sensor"&location="VCAC") [low-limit="0.6",high-limit="1.3",type="Voltage",description="CPU A, Core Voltage"]
SET_PROPERTY (class="Sensor"&location="VCBC") [low-limit="0.6",high-limit="1.3",type="Voltage",description="CPU B, Core Voltage"]
SET_PROPERTY (class="Sensor"&location="Ve1S") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PCIe Slot 1, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="Ve2S") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PCIe Slot 2, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="Ve3S") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PCIe Slot 3, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="Ve4S") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PCIe Slot 4, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VeAS") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PCIe BoostA, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VeBS") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PCIe BoostB, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VH1Z") [low-limit="11.4",high-limit="12.6",type="Voltage",description="HDD1, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VH2Z") [low-limit="11.4",high-limit="12.6",type="Voltage",description="HDD2, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VH3Z") [low-limit="11.4",high-limit="12.6",type="Voltage",description="HDD3, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VH4Z") [low-limit="11.4",high-limit="12.6",type="Voltage",description="HDD4, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VO0Z") [low-limit="11.4",high-limit="12.6",type="Voltage",description="ODD, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VH5Z") [low-limit="4.5",high-limit="5.5",type="Voltage",description="HDD+ODD, 5V Voltage"]
SET_PROPERTY (class="Sensor"&location="VM1S") [low-limit="1.43",high-limit="1.57",type="Voltage",description="PP1V5_S3_MEMA Voltage"]
SET_PROPERTY (class="Sensor"&location="VM2S") [low-limit="1.43",high-limit="1.57",type="Voltage",description="PP1V5_S3_MEMB Voltage"]
SET_PROPERTY (class="Sensor"&location="VN0C") [low-limit="1.07",high-limit="1.13",type="Voltage",description="PP1V1_S0_IOH Northbridge Voltage"]
SET_PROPERTY (class="Sensor"&location="Vp0C") [low-limit="11.4",high-limit="12.6",type="Voltage",description="PSU, 12V Voltage"]
SET_PROPERTY (class="Sensor"&location="VCAB") [low-limit="1.00",high-limit="1.30",type="Voltage",description="PPVTT_S0_CPUA Voltage"]
SET_PROPERTY (class="Sensor"&location="VCBB") [low-limit="1.00",high-limit="1.30",type="Voltage",description="PPVTT_S0_CPUB Voltage"]
SET_PROPERTY (class="Sensor"&location="VS1C") [low-limit="1.00",high-limit="1.10",type="Voltage",description="PP1V05_S0_SB Voltage"]
SET_PROPERTY (class="Sensor"&location="VS2C") [low-limit="1.43",high-limit="1.58",type="Voltage",description="PP1V5_S0_SB Voltage"]
SET_PROPERTY (class="Sensor"&location="VS8C") [low-limit="3.14",high-limit="3.47",type="Voltage",description="PP3V3_S5 Voltage"]
REMOVE_DEVICE (class="Sensor") (class="Sensor"&type="?")
REMOVE_DEVICE !(class="Processor"&location="1") (class="Sensor"&location="VCBB")
REMOVE_DEVICE !(class="Processor"&location="1") (class="Sensor"&location="VCBC")
REMOVE_DEVICE !(class="Processor"&location="1") (class="Sensor"&location="ICBB")
REMOVE_DEVICE !(class="Processor"&location="1") (class="Sensor"&location="ICBC")
REMOVE_DEVICE !(class="Processor"&location="1") (class="Sensor"&location="IMBS")
REMOVE_DEVICE (class="Memory"&location="DIMM 1"&ecc="FALSE") (class="Sensor"&location="TMA1")
REMOVE_DEVICE (class="Memory"&location="DIMM 2"&ecc="FALSE") (class="Sensor"&location="TMA2")
REMOVE_DEVICE (class="Memory"&location="DIMM 3"&ecc="FALSE") (class="Sensor"&location="TMA3")
REMOVE_DEVICE (class="Memory"&location="DIMM 4"&ecc="FALSE") (class="Sensor"&location="TMA4")
REMOVE_DEVICE (class="Memory"&location="DIMM 5"&ecc="FALSE") (class="Sensor"&location="TMB1")
REMOVE_DEVICE (class="Memory"&location="DIMM 6"&ecc="FALSE") (class="Sensor"&location="TMB2")
REMOVE_DEVICE (class="Memory"&location="DIMM 7"&ecc="FALSE") (class="Sensor"&location="TMB3")
REMOVE_DEVICE (class="Memory"&location="DIMM 8"&ecc="FALSE") (class="Sensor"&location="TMB4")So once you edit you have to recalculate the checksum from Fsys to the last byte before the checksum, correct?
Yes, CRC32, than convert to big endian and insert it back
Once this is GA released, will corrupt NVRAM still present an issue? Would it be wise to undertake steps to check whether my current firmware has been corrupted (the machine has had a Windows EFI installation, but I am not certain whether this was before, during or after .87 firmware....).
Many thanks
BD.
Many thanks
BD.
Yes, efi2flasher keeps the NRAM volume as is.
Macschrauber got a used MP4,1 and dumped every step of the way, from MP41.0081.B00 to 140.0.0.0.0. Since MP41.0081.B00 had the InstallPhaseList plist, every one of the other dumps (MP51.007F.B03, MP51.0089.B00, 138.0.0.0.0 and 140.0.0.0.0) had it too.
Yes, it is.
(y) many thanks.
[doublepost=1539964835][/doublepost]Wouldn't resetting the NVRAM at startup with command-option-P-R be a quick fix for this?
[doublepost=1539964835][/doublepost]Wouldn't resetting the NVRAM at startup with command-option-P-R be a quick fix for this?
Nope, it's not in the user accessible area of the volume, it's in one of the private ones.
You can fix that by changing the default boot to Windows, but you will need to use the Option key to boot on Mac.
That's the only solution I know to this
I have the Problem that i updated my Mac Pro 5,1 to the Mojave Beta, before i was able to install the mojave beta he forced me to update to firmware MP51.0085.B00 - today it updated to Mojave 10.14.1 Beta and still the same Firmware. When it try to install "Normal" Mojave he tells me that i cant install it because i need a Metal card and no File Vault enabled. But i have a Metal Card (RX580 Pulse) and i was able to install the mojave beta...
I tried to start the Installer from the RecoveryHD pkg - same result.
So i think i need to do a clean install with a changed firmware folder to fix that? or do i just need to replace my gpu with the original one and start the mac by holding the power button?
Because when i installed the mojave beta , i started the installer - restarted the pc changed gpu to the original one to get the firmware update running, changed the gpu back to the RX580 and it worked. maybe the last setup tried to do the firmware update but was not able to do it with the RX580. i know that if i get my firmware to 140.000 i will never have that problem with that gpu again.
I tried to start the Installer from the RecoveryHD pkg - same result.
So i think i need to do a clean install with a changed firmware folder to fix that? or do i just need to replace my gpu with the original one and start the mac by holding the power button?
Because when i installed the mojave beta , i started the installer - restarted the pc changed gpu to the original one to get the firmware update running, changed the gpu back to the RX580 and it worked. maybe the last setup tried to do the firmware update but was not able to do it with the RX580. i know that if i get my firmware to 140.000 i will never have that problem with that gpu again.
That's the bug of the installer. You have to run the installer in HS, not in any Mojave (regardless beta or not).
Ok, but how to get back to HS?
Just via new clean install?
because i cant install it from the appstore...
I think you will need a clean installation. Most likely need to create a bootable installer.
I keep a HS backup boot driver just for this kind of issue.
All info and links for High Sierra are here MP5,1: What you have to do to upgrade to Mojave.
Last edited by a moderator:
Any evidence if having a dedicated Bootcamp drive vs a splitting one into partitions makes a difference in corruption?
The multiple SecureBoot certificates problem is exclusively caused by UEFI Windows installs, not with BootCamp or CSM ones.
Interesting this article talks more about T2 chips (not cMP) but:
" There’s an embedded x509 cert in there, coming from “Apple X86 Secure Boot Root CA - G1” and “T8012Mac-TssLive-ManifestKeyGlobal-RevB-DataCenter”, for validating the signature."
http://michaellynn.github.io/2018/07/27/booting-secure/
" There’s an embedded x509 cert in there, coming from “Apple X86 Secure Boot Root CA - G1” and “T8012Mac-TssLive-ManifestKeyGlobal-RevB-DataCenter”, for validating the signature."
http://michaellynn.github.io/2018/07/27/booting-secure/