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DMxxx controller and auto XOR key synthesis ?

Posted: July 2nd, 2024, 5:50
by Gregory
Do you plan to add DM XOR key synthesis in the near future? Recently these controllers have started to appear and what is important is that the XOR mechanism is similar to SM32xx, i.e. XOR is modified by BB. You recently created a new XOR "DM_unknown(18336b_384p_xoredSA_ECC)_1775CE.xor" for our case. I have another case with this XOR, but everything goes wrong when it reaches BB - I checked and XOR is also applied to BB.

Is there a chance you will develop an automatic method for this? It can probably be done manually, but it's a lot of work.

Thanks in advance for your answer.

btw. this white horizontal white stripes are data, in DM, XOR before ECC.

ps. on attachment XOR comparison: top after BB cutout, bottom without BB cutout (pink-ECC, green-data area)

Re: DMxxx controller and auto XOR key synthesis ?

Posted: July 19th, 2024, 16:53
by Sasha Sheremetov
Can we have some 10-20 blocks from it? Preferably with xor key. I appreciate if you can send a link in ticket.

Re: DMxxx controller and auto XOR key synthesis ?

Posted: July 29th, 2024, 15:06
by Amarbir[CDR-Labs]
Gregory ,
I have not come across these controllers here in india ,But they are interesting . Anything that we should be aware of other then what you wrote here when we receive a case

Re: DMxxx controller and auto XOR key synthesis ?

Posted: July 30th, 2024, 3:17
by Gregory
Amarbir[CDR-Labs] wrote:Gregory ,
I have not come across these controllers here in india ,But they are interesting . Anything that we should be aware of other then what you wrote here when we receive a case

XOR every sector with 1775CE XOR depending on the length of the sector. Sectors leangth may be different when they contain BB, then build new XOR and cut BB ater that.

Re: DMxxx controller and auto XOR key synthesis ?

Posted: July 30th, 2024, 3:40
by Gregory
Sasha Sheremetov wrote:Can we have some 10-20 blocks from it? Preferably with xor key. I appreciate if you can send a link in ticket.

Extracted 20 blocks with XOR, Ticket #6834, I created XOR for my case manualy. I am attaching a diagram of how I do it manually, maybe it will make it easier for you to work on developing DM AI XOR.

Re: DMxxx controller and auto XOR key synthesis ?

Posted: July 31st, 2024, 8:25
by Gregory
Update my reserch, it looks like this XOR will also be able to start from different pages and also alternate inversions of these pages. I have another case with DMxxx but from now on I will call it DM8381 or DM83xx - I see that Arvika had this controller in a non-monolithic NAND with an XOR signature 8E8464, i.e. this signature is second page of the base XOR 1775CE and is in inversion. I now have another case with 5F29F8 XOR which is located on page 187 of 1775CE XOR and also has every other page in inversion compared to the base XOR.

ps. our new case not have BB but still need manualy created new XOR from 1775CE because have bad read quality and ofc ECC ater XOR :)

ps2. MichaƂ, can you tell us about your experience with the new DM controllers, which would allow us to speed up the work on automatic AI XOR DM in Rusolut?

Re: DMxxx controller and auto XOR key synthesis ?

Posted: August 6th, 2024, 11:59
by Igor_Loskutov
Hi there,
we've added to the short list AI XOR key generatimg for this controller. Hope it will be done with the next update.

Re: DMxxx controller and auto XOR key synthesis ?

Posted: August 14th, 2024, 9:46
by Sasha Sheremetov
We are alpha-testing new AI XOR for DM controllers now.
Gregory, thanks for the idea!

Re: DMxxx controller and auto XOR key synthesis ?

Posted: September 5th, 2024, 11:10
by Igor_Loskutov
Hi Gregory, have you tried the new AI DM XOR with your cases?

Re: DMxxx controller and auto XOR key synthesis ?

Posted: September 9th, 2024, 6:19
by Gregory
Yes I try once and it working, however, I don't know how it work with bad columns, not tested.