Someone tried to add read retry to pc3000 flash?

[csava]

Someone tried to add read retry to pc3000 flash?
Thank you very much for your information about read retry

[Amarbir[CDR-Labs]]

Well,
Several Read Retry Options Exist In the tool for many flash devices

[ddrecovery]

Read Retry is available by right clicking on the transformation graph and on the tools menu.
It is also available while in the Map page when correcting bad ECC.

[Bolo]

As understand user is asking about possibility to add OWN RetryRetry (registers and their values)

Answer is: No ;(((

They not allow to add own code and it's bad.....

[ddrecovery]

As understand user is asking about possibility to add OWN RetryRetry (registers and their values)

Answer is: No ;(((

They not allow to add own code and it's bad.....

[Tomset]

Bolo,

They not allow to add own code and it's bad.....

Not true.
The kernel functions are available, there is documentation, you can request.
But utility functions are not available.
You can write your own utility completely or connect a script.

[Bolo]

@Tomset: It's totally diffrent answer which I recive from Technical Support, when I ask such question sometime ago:

"Impossible to add your own if you are not a developer"

Can you then answer from whom I can request such documentation if TS says it's not possible ?

[Tomset]

Bolo,
Аsk for a document how to write user scripts.

[csava]

Well,
Several Read Retry Options Exist In the tool for many flash devices

Well, so far, there is no public device that can add read retry by itself, right? Although some read retry is provided, it is not perfect for me, such as ad3a1803, Toshiba bisc2, micron L95 l06b b0kb B16 B17

[csava]

Bolo,
Аsk for a document how to write user scripts.

I only hope that pc3000 flash can provide the option of adding read retry, and tell the user the rules related to commands and addresses. After all, pc3000 flash is too slow to update the software, so it's a great idea to open options for users to add rules themselves

[Bolo]

@csava: You can add own RR in Flash Extractor as well as VNR (Rusolut) easily

@Tomset: I maked a ticket and request documentation..... let's wait then

[Bolo]

@Tomset: Answer "There is no any manual for PC-3000 Flash scripts."

[Amarbir[CDR-Labs]]

@Tomset: Answer "There is no any manual for PC-3000 Flash scripts."

Well ,
Did They give this reply as you asked now ,is that what you are saying

[arvika]

Well,
Several Read Retry Options Exist In the tool for many flash devices

Well, so far, there is no public device that can add read retry by itself, right? Although some read retry is provided, it is not perfect for me, such as ad3a1803, Toshiba bisc2, micron L95 l06b b0kb B16 B17

RR algo - VNR and FE - you can add manually, it support own RR modes. PC3K not possible add own.
ECC algo - VNR supports own, FE and PC3K not possible use own.
XOR algo - VNR possible use own, FE not possible, PC3000 can't use own (but not sure).

[csava]

Well,
Several Read Retry Options Exist In the tool for many flash devices

Well, so far, there is no public device that can add read retry by itself, right? Although some read retry is provided, it is not perfect for me, such as ad3a1803, Toshiba bisc2, micron L95 l06b b0kb B16 B17

RR algo - VNR and FE - you can add manually, it support own RR modes. PC3K not possible add own.
ECC algo - VNR supports own, FE and PC3K not possible use own.
XOR algo - VNR possible use own, FE not possible, PC3000 can't use own (but not sure).

How to add RR to FE? I didn't find any documentation

[jeremyb]

Well,
Several Read Retry Options Exist In the tool for many flash devices

Well, so far, there is no public device that can add read retry by itself, right? Although some read retry is provided, it is not perfect for me, such as ad3a1803, Toshiba bisc2, micron L95 l06b b0kb B16 B17

RR algo - VNR and FE - you can add manually, it support own RR modes. PC3K not possible add own.
ECC algo - VNR supports own, FE and PC3K not possible use own.
XOR algo - VNR possible use own, FE not possible, PC3000 can't use own (but not sure).

How to add RR to FE? I didn't find any documentation

In FE, click on the lightning bolt..
Test Retry - Try Known Retry Values (Can also be used to get a base result for Test Retry Tune)
Test Retry Tune (Tweaks the Retry Value by incrementing the registers)
Test Retry Random (Sends random garbage to the registers and sees what sticks)

Then take that value and go to NAND Reader under Conf -> Config .. copy and paste it into Retry...

[jeremyb]

A lot of my work is reverse engineering RR for Soft-Center/Sergey, so I’d like to think I’m a good source.
How Sergey chooses to implement this information is on him.

First, I don’t like calling them RR codes, the phrase has no meaning, I prefer “sensitivity registers”.

Modern NAND chips are broken into three pages (Lower, Middle Upper), even on NAND using a STD interface, not just WL. Let’s say you read a NAND chip and you see a band of uncorrectable errors (page address % 3) = 2 (middle) it probably has an incorrect RR value. If you modify the registers responsible for that band until you find “the sweet spot” you will get a range of values that give you a good read. If you run ECC combine over multiple reads using different registers in that range you’ll get a perfect image.

This method works on SK Hynix, Samsung and Toshiba/SanDisk NAND.

Lots of different factors that go into choosing a proper RR value besides setting register 0xB0 to 0x4F which is why RR is so poorly understood.

“Test Retry” – Registers can be initialized with KNOWN starting values that can get you in the correct range. FE calculates the best value based on the number of corrected errors.
“Test Retry Tune” – IMHO terrible solution, but I digress, this will take your Test Retry value and brute force the best register value by corrected errors. It’s slow, unoptimized, and doesn’t take into account any geometrical factors.
“Test Random” – Sends random data to the registers, like winning the lotto.

RR is actually pretty cool, it's not about taking damaged NAND and making it usable, more like finding taking good NAND and making it readable.

Attachments

[HaQue]

how much of this stuff appears in the datasheets?

[arvika]

None. It is reverse engineering.

[csava]

Thank you for your help. I need more tests to master. It sounds cool to be able to regenerate broken flash data