Actually I published a version myself for Linux.

https://gist.github.com/FlyGoat/5f0dba5b5ccc1b6ab73023489e1e989a

But really appreciate that we have a much more elegant C version :-)

Just letting you know that it also works for my computer with the board version SDK0J40697 WIN as reported by /sys/class/dmi/id/board_version.

I have a Yoga Slim 7 14IIL05 (is an intel version)
Does it make it a difference that is DHCM instead of a DMCM

Highly appreciate your work!
On the latest version, when running make I get the following error:

/yoga-bios-unlock$ make
cc -o ./yoga-bios-unlock ./src/yoga-bios-unlock.c -O2 -Wall -Wextra -Wfloat-equal -Wshadow -Wstrict-prototypes -Wstrict-overflow=5 -Wcast-qual -Wconversion -Wunreachable-code
./src/yoga-bios-unlock.c: In function ‘is_yoga’:
./src/yoga-bios-unlock.c:66:17: error: redefinition of ‘bios_version_34’
   66 |   dmi_strings_t bios_version_34 = { .string = __BIOS_VERSION_34, .next = &bios_version_36 };
      |                 ^~~~~~~~~~~~~~~
./src/yoga-bios-unlock.c:65:17: note: previous definition of ‘bios_version_34’ was here
   65 |   dmi_strings_t bios_version_34 = { .string = __BIOS_VERSION_36, .next = &bios_version_38 };
      |                 ^~~~~~~~~~~~~~~
./src/yoga-bios-unlock.c:66:75: error: ‘bios_version_36’ undeclared (first use in this function); did you mean ‘bios_version_34’?
   66 |   dmi_strings_t bios_version_34 = { .string = __BIOS_VERSION_34, .next = &bios_version_36 };
      |                                                                           ^~~~~~~~~~~~~~~
      |                                                                           bios_version_34
./src/yoga-bios-unlock.c:66:75: note: each undeclared identifier is reported only once for each function it appears in
make: *** [Makefile:4: yoga-bios-unlock] Error 1

Hi, I got this error message under ubuntu 20.04. It is my hw or some sw incompatibility?

sudo ./yoga-bios-unlock --read Run in read-mode Be aware that readmode temporarily changes value of port 0x72 to index 0xf7 WARNING: use at your own risk! Agree? (y/n) y Can't set I/O privilege level (Operation not permitted)

I've just tested this on DMCN27WW and it works.

Also, Agreed should be Y/N. Now it is: Agree? (y/Y)

Good day. Do people have any bios dump that can be uploaded through the programmer?

It looks like I own one with a different board type.

$ sudo ./yoga-bios-unlock --read
Run in read-mode
Be aware that readmode temporarily changes value of port 0x72 to index 0xf7
board_version does not match (SDK0J40700 WIN  )
Wrong device, aborting!

Here are some relevant information:

Handle 0x0001, DMI type 1, 27 bytes
System Information
	Manufacturer: LENOVO
	Product Name: 82A2
	Version: Yoga Slim 7 14ARE05
	Serial Number: XXXXXXXXXX
	UUID: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
	Wake-up Type: Power Switch
	SKU Number: LENOVO_MT_82A2_BU_idea_FM_Yoga Slim 7 14ARE05
	Family: Yoga Slim 7 14ARE05

BIOS Information
	Vendor: LENOVO
	Version: DMCN32WW
	Release Date: 07/14/2020
	Address: 0xE0000
	Runtime Size: 128 kB
	ROM Size: 15488 kB
	Characteristics:
		PCI is supported
		BIOS is upgradeable
		BIOS shadowing is allowed
		Boot from CD is supported
		Selectable boot is supported
		EDD is supported
		Japanese floppy for NEC 9800 1.2 MB is supported (int 13h)
		Japanese floppy for Toshiba 1.2 MB is supported (int 13h)
		5.25"/360 kB floppy services are supported (int 13h)
		5.25"/1.2 MB floppy services are supported (int 13h)
		3.5"/720 kB floppy services are supported (int 13h)
		3.5"/2.88 MB floppy services are supported (int 13h)
		8042 keyboard services are supported (int 9h)
		CGA/mono video services are supported (int 10h)
		ACPI is supported
		USB legacy is supported
		BIOS boot specification is supported
		Targeted content distribution is supported
		UEFI is supported
	BIOS Revision: 1.32
	Firmware Revision: 1.2

BIOS Language Information
	Language Description Format: Long
	Installable Languages: 4
		en|US|iso8859-1
		fr|FR|iso8859-1
		ja|JP|unicode
		zh|TW|unicode
	Currently Installed Language: en|US|iso8859-1

What do you think: should I take the risk and try altering the default BOARD_VERSION definition?

I read about a method here and here to achieve bios unlock that should work with other models of Lenovo notebooks. I'm yet to try it out on my Yoga Slim 7 14ARE05 but it is here for anyone who is brave enough to try it:

"1. Turn off OneKeyBattery mode in BIOS setup (this won't work with it enabled), save settings, power off
2. Type, with the laptop powered off: F1 1 Q A Z F2 2 W S X F3 3 E D C F4 4 R F V F5 5 T G B F6 6 Y H N. If you notice the pattern, it's just going down the column from F1 to the letter in the last keyboard row, from F1 to F6.
3. Boot the laptop with F2 pressed to get into BIOS as usual, you'll get into the BIOS but with a few options more unlocked."

Look what I found:

https://github.com/DavidS95/Smokeless_UMAF

altough I haven't tried yet.

I understand that this is probably not the right place for such a question, but:

1. do you believe that this can be performed on a similar device such as the Ideapad 5 14are05?
2. how would one go about doing so?
   Thanks!

I want to take my laptop to a service center. And if they see an unlocked BIOS, then the guarantee could be lost. How can you believe him in his original state?

This is great work, thank you.
Do you think it would be possible to do for the 15ITL05 BIOS as well?

Is it possible to use this method for bios version DMCN36WW ?

Hi, do you think it is safe to roll back the bios to an earlier version?
From warranty service I got back the notebook with bios version 38. I want to go back to 32.

This version is published at 29 Sept. I will try to unlock it for disable S3 deep to solve sleep problem on linux. Should i try? or is there any files/instructions for downgrading bios version? I couldnt see it on lenovo support page.

When I run the command ./yoga-bios-unlock --unlock I get:

Run in unlock mode
board version does not match
Wrong device, aborting!

cat /sys/class/dmi/id/board_version returns SDK0J40709 WIN
cat /sys/class/dmi/id/bios_version returns DMCN27WW

So everything is supported and it should work (This is also the data that shows in the bios), but the check apparently fails. I've seen in other bug reports that the result that I get usually includes the detected board version, but mine for some reason doesn't, so I assume that it failed to get the value.

I don't exactly know how the program works, but would it make sense to set those values manually and then run the program with those manual values? And if yes, how would I go about doing this?

I got a message saying my board version did not match, even though it should.
My board version is SDK0J40709 WIN.
I suspect the row of question marks has something to do with it.

The unlock worked fine when I used --force.

Run in read mode
Be aware that readmode temporarily changes value of port 0x72 to index 0xf7
board_version does not match (SDK0J40709 WIN   ��������������������������������)
Wrong device, aborting!

Just noting here for anyone who comes across this in the future -- I attempted to force unlock on a Lenovo Yoga Pro 9 16IRP8 with:

BIOS_VERSION: KVCB35WW
BOARD_VERSION: SDK0T76461 WIN

and it was unsuccessful.

Laptop is not bricked, seemingly nothing changed at all; regular bios is healthy, no boot issues. I thought risking the brick was worth it.

Thanks @esno for all your hard work.

Hello,

I'm trying to unlock the UEFI on my Slim 7 ProX, as there appears to be some issues running Xen, this could be related to some weird Microsoft thing Lenovo have enabled.

I have UEFITool working with a InsydeH20 .fd from here: https://pcsupport.lenovo.com/ch/en/products/laptops-and-netbooks/yoga-series/yoga-slim-7-prox-14arh7/downloads/driver-list/component?name=BIOS%2FUEFI

Is it possible to unlock more UEFI options for this laptop?

Cheers

Is it planned to support the bios DMCN43WW?

thank you very much!
My yoga sleeps properly now on ubuntu :)
DMCN29WW wasn't on your list yet
hardware bought this week in Germany if it's of any interest

Thank you for nice piece of software.
I tuned the code and checked that it works also in bios version DMCN35WW.

Successfully tested

I ran the file and it ate my cat, and burned my house down :-)

No, the reason i'm making this ticket is if i can peruse you to take a look at the lenovo z490 based mainboard, where they have locked features as xmp in the advanced section.. Making installed custom ram running at 50%.. while xmp is on the board..

thxn

Latest bios version: https://download.lenovo.com/pccbbs/deskt...y12usa.exe
Files after extraction: https://www.dropbox.com/t/tsU5NUkumVdxDwJa

hey @esno thank's for this great tool!

When running ./yoga-bios-unlock --read I get this output here (same when running with sudo)

Run in read-mode
Be aware that readmode temporarily changes value of port 0x72 to index 0xf7
board_version does not match (SDK0J40709 WIN   ��������������������������������)
Wrong device, aborting!

This are my specs:

BIOS Information
        Vendor: LENOVO
        Version: DMCN34WW
        Release Date: 08/17/2020
System Information
        Manufacturer: LENOVO
        Product Name: 82A2
        Version: Yoga Slim 7 14ARE05

The title is self explanatory,
I have absolutely zero knowledge about accessing Extend CMOS Index/Data Port but I am guessing(From my basic understanding) it would be better to save the original value aka index port position and after reading 0x73 set the index port back to the original?
so if other software that accesses the 0x73 and doesn't make sure it accesses correct index port doesn't end up messing something up?