I'm talking about EFI modification.
just need to understand how CSM iMac differs from CMP
just need to force Legacy to boot the system with NVME, register the resolution as a native device.
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MP 1,1-5,1 Support NVME boot on Legacy for Mac Pro 5.1
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just need to understand how CSM iMac differs from CMP
just need to force Legacy to boot the system with NVME, register the resolution as a native device.
DUET allows a Legacy UNIT to execute uEFI BOOT on ports that support such boots.
The OP wants a uEFI UNIT to run Legacy BOOT on ports that DO NOT support this.
Note differing positions of "Boot" and "Unit":
| SUBJECT | UNIT TYPE | BOOT TYPE |
| DUET | Legacy | uEFI |
| OP | uEFI | Legacy |
While a cMP, as with most early uEFI units, can run Legacy Boot without issue on ports that support Legacy Boot, the OP wants this on ports (PCIe) not designed to boot such on cMP.
Legacy boot requires BIOS Interrupt Call 13hex (INT 13h).
cMP does not have INT 13h on the PCIe ports.
No INT 13h = No Legacy Boot.
Infer difference from above.
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Got it thanks. In this case the OP should grab the iMac firmware, disassemble it, grab the cMP firmware disassemble it. Compare the firmwares and add the missing call. Easy
.Or OP ca try NOPing the function call (if possible) with opencore by finding what program is calling it.
Guide to Hacking
Guide to Hacking. GitHub Gist: instantly share code, notes, and snippets.
gist.github.com
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Apparently possible ... along with emulating the item as @joevt suggested here:
Bare Metal Windows on cMP
Since the BIOS stuff is loaded by EFI using the Boot Camp EFI app, then maybe it could be extended if you can figure out how the int13 is done for the four built-in SATA ports. Is the BIOS code calling EFI code to do the read/write or is there an entire BIOS driver for the SATA ports? To find...
forums.macrumors.com
It was all sounding good until he started talking about me patching RefindPlus to look at things further.
I have penciled that in for consideration after retirement and completing a few things on the post-retirement bucket list. OK, an exaggeration, but let's just say it is not a current priority.
@tsialex did point the OP to an OpenCore dev that might entertain the idea earlier in this thread.
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I really hope that my 29 bucks will not be laughed at when I buy version 3.3q
but I'll check.
Yes, this will solve the problem with Windows 7 for many people who will say - this is cool! that you can, for example, install the system on a relatively fresh Mac.
but the problem of legacy and permission to use nvme will not give you peace to just forget it.
Ahn? There is absolutely ZERO support for TB inside the Mac Pro BootROM. Why do you think that just adding a TB adapter that barely works will bring any support for Legacy OS with NVMe?!? No Interrupt 13h support for PCIe with the MacPro5,1 firmware, adding a TB card won't change that.
Only Macs that support UEFI Class 2 have support for PCIe INT 13h.
I was thinking more like adding option ROM to the NVME. AFAIK the thunderbolt firmware has been modified to make it work on the cMP. Isn’t that how Samsung 950 pro boots on systems without INT 13h? Through option ROM?
winraid.level1techs.com
Samsung NVMe legacy BOOT ROM present on 950 Pro
Hello everyone! The samsung 950 Pro is a rare example of an NVMe SSD which has option rom, allowing it to boot on legacy bios platforms. Did anyone attempt to extract it, and try to use it to boot similar sm951/pm951 SSDs? (via injecting into bios, loading the rom via plop…) I searched for that...
winraid.level1techs.com
Even if it is via INT 13h, we are supposing that is just the INT 13h and nothing more is required like some sort of NVMe EFI module, Samsung 950 is not compatible with Macs. I have one here and tested it extensively, does not even work anymore with recent Intel UEFI class 3 motherboards (only have SecureBoot and no more CSM), while still work with recent AMD ones.
Most OPROMs designed for PCs are not compatible with Macs, see Samsung 950, Sonnet Tempo that mess with the Boot Picker and all other PCIe cards that do not work with Macs or behave very badly in one way or the other when installed to one.
Down in the same thread there is actually a successful BIOS upgrade
winraid.level1techs.com
But unfortunately for Phoenix/Award mainboard BIOS.
[Guide] Award/Phoenix BIOS Modding
Preliminary Notes: Before you start with the BIOS modding procedure, it is strongle recommended to read carefully the separately published chapter “BIOS Modding: Introduction and Preparations” (>Link<). For users of a Gigabyte mainboard with an Award BIOS I recommend to have an additional look...
winraid.level1techs.com
Down in the same thread there is actually a successful BIOS upgrade
But unfortunately for Phoenix/Award mainboard BIOS.[Guide] Award/Phoenix BIOS Modding
Preliminary Notes: Before you start with the BIOS modding procedure, it is strongle recommended to read carefully the separately published chapter “BIOS Modding: Introduction and Preparations” (>Link<). For users of a Gigabyte mainboard with an Award BIOS I recommend to have an additional look...
Flawed idea for the discussion of this thread, since won't add INT 13h support for the Mac Pro for a PCIe drive and the 950 PRO OPROM is not compatible with Macs.
Must be some specific firmware as the one I have (Tempo Pro) can boot fine Windows. I have to double check if it can boot both Legacy and UEFI Windows.
Old plain Sonnet Tempo from early 2010s. I have one and @h9826790 also have it:
Sonnet Tempo & dual SSDs - worth it in 2019?
For info, this TempoSSD card only affect the native Apple boot manager. OpenCore boot picker is not affected. I can boot from my TempoSSD via OpenCore boot picker. Be careful the Fusion card is not bootable. It looks similar to the TempoSSD card, however, it's a completely different product...
forums.macrumors.com
Mine is slightly different:
forums.macrumors.com
It looks like I can boot EFI Windows there. Will check Legacy too.
If the error is 0x80300024 there is a workaround:
How to: Boot Camp without a Boot Screen
It is a mix. The BOOTCAMP is a legacy Windows 7 (you don't see it in my original post as I installed it later). BOOTCAMPSSD is an EFI Windows 10 on my Sonnet Tempo SSD Pro Plus. The WIN10SSD is an EFI Windows on a NVME on a DT-120. I can boot to legacy or EFI Windows, Recovery etc. with the same...
forums.macrumors.com
If the error is 0x80300024 there is a workaround:
Workaround for 0x80300024 Error In Windows 10/11 Setup
Error 0x80300024 is caused by inability of Windows Setup to correctly recognize internal bootable storage device. Workaround is to transfer the bootloader, BCD registry hive and bootable ramdisk to internal bootable storage device and boot from that device.
www.prime-expert.com
Guys, we are already going way off topic.
If anyone has the opportunity to buy the latest version of Flashboot pro 3.3q for testing, I would be very grateful.
Due to the payment system and the place where I live, I can’t buy this program.
perhaps it will solve all the problems for users of windows 7 on CMP and new macbooks
If anyone has the opportunity to buy the latest version of Flashboot pro 3.3q for testing, I would be very grateful.
Due to the payment system and the place where I live, I can’t buy this program.
perhaps it will solve all the problems for users of windows 7 on CMP and new macbooks
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Here is a crazy thought.
If you could find a way to get a Legacy Windows instance on the NVMe stick, by cloning it for instance, I think there is a chance you might be able to boot it with rEFInd or RefindPlus as I can't see anywhere it might need INT 13h input in the code for booting Legacy/CSM. Need to test this at some point to verify.
If you could find a way to get a Legacy Windows instance on the NVMe stick, by cloning it for instance, I think there is a chance you might be able to boot it with rEFInd or RefindPlus as I can't see anywhere it might need INT 13h input in the code for booting Legacy/CSM. Need to test this at some point to verify.
In the case of Windows 7 it will still need the Nvme driver installed and some Hotfix if I am not mistaken?
I am assuming any other stuff for the stick to work is present (If running Mac OS or just a data drive for instance).
Might be off base that the interrupt can be bypassed by these as the code only goes as far as loading a child image after getting device paths etc from the MBR and other requirements are probably triggered by the image.
Just need to check at some point.
EDIT
You maybe meant the driver within the OS for NVME support. Yes, this would definitely be needed.
I will test on Windows 10 which should have this support in place.
Might be off base that the interrupt can be bypassed by these as the code only goes as far as loading a child image after getting device paths etc from the MBR and other requirements are probably triggered by the image.
Just need to check at some point.
EDIT
You maybe meant the driver within the OS for NVME support. Yes, this would definitely be needed.
I will test on Windows 10 which should have this support in place.
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There is some weird hack:
mrlithium.blogspot.com
How To Boot an NVME SSD from a Legacy BIOS (non UEFI) w/ Intel 750 Series SSD
This tutorial is about LEGACY BIOSes. This is something i've been wanting to try for a very long time, since I have an older X58 motherboa...
mrlithium.blogspot.com
Difficult read and didn't read all, but looks like creating a pseudo uEFI disk setup and using DUET to boot as it does for legacy units, as the subject one, to boot real uEFI setups.
The legacy board probably had INT 13h everywhere but as @tsialex hinted earlier, some other limitation might have been what was preventing NVMe boot on the unit and needed to be hacked accordingly.
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