ADJUSTING STORAGE DEVICE PARAMETERS BASED ON RELIABILITY SENSING

• US 20110252289A1
• Filed: 04/08/2010
• Published: 10/13/2011
• Est. Priority Date: 04/08/2010
• Status: Abandoned Application

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Buch, Bruce Douglas, Patapoutian, Ara
• Application Number:
  US12/756,974
• Publication Number:
  US 20110252289A1
• Time in Patent Office: Days
• US Class Current: 714/763
• CPC Class Codes: G06F 11/1048 using arrangements adapted for a specific error detection or correction feature
• CPC Class Codes: H03M 13/1102 Codes on graphs and decoding on graphs, e.g. low-density parity check [LDPC] codes
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• CPC Class Codes: H03M 13/152 Bose-Chaudhuri-Hocquenghem [BCH] codes
• CPC Class Codes: H03M 13/29 combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
• CPC Class Codes: H03M 13/2957 Turbo codes and decoding
• CPC Class Codes: H03M 13/353 Adaptation to the channel

Abstract

In general, this disclosure is directed to techniques for adjusting storage device parameters based on reliability sensing. According to one aspect, a method includes retrieving a codeword from a plurality of data blocks within a storage device, wherein each of the data blocks stores a respective portion of the codeword, generating a detected value for a bit within a first portion of the codeword based on information related to a reliability of a data block associated with the first portion, and performing error correction on a second portion of the codeword based on the detected value for the bit within the first portion of the codeword. According to another aspect, a method includes obtaining information related to a reliability of a data block within a storage device, and adjusting a data capacity for the storage device based on the information related to the reliability of the data block.

Claims

1. A method comprising:

retrieving a codeword from a plurality of data blocks within a storage device, wherein each of the data blocks stores a respective portion of the codeword;

generating a detected value for a bit within a first portion of the codeword based on information related to a reliability of a data block associated with the first portion; and

performing error correction on a second portion of the codeword based on the detected value for the bit within the first portion of the codeword.

2. The method of claim 1, wherein the detected value comprises a hard detected value.

3. The method of claim 1, wherein the detected value comprises a soft detected value.

4. The method of claim 3, wherein the soft detected value comprises a value generated based on a probabilistic function.

5. The method of claim 3, wherein the soft detected value comprises a log-likelihood ratio (LLR).

6. The method of claim 1, further comprising:

generating sets of detected values based on information related to a respective reliability for each of the data blocks, wherein each set of detected values includes detected values associated with a respective portion of the codeword; and

performing error correction on the second portion of the codeword based on the sets of detected values.

7. The method of claim 6, further comprising:

performing codeword portion-specific error corrections on the portions of the codeword to generate codeword portion-specific error correction information,

wherein generating the sets of detected values comprises generating the sets of detected values based on information related to the respective reliability for each of the data blocks and the codeword portion-specific error correction information.

8. The method of claim 7,

wherein the sets of detected values are a first group of detected values,

wherein the method further comprises generating a second group of detected values for the portions of the codeword based on information related to a respective reliability of each of the data blocks, and

wherein performing the codeword portion-specific error corrections comprises performing codeword portion-specific error corrections on the portions of the codeword based on the second group of detected values to generate the codeword portion-specific error correction information.

9. The method of claim 6, wherein performing the error correction on the second portion of the codeword comprises:

performing codeword portion-specific error corrections on the portions of the codeword to generate codeword portion-specific error correction information; and

performing the error correction on the second portion based on codeword portion-specific error correction information associated with the first portion of the codeword.

10. The method of claim 1, wherein each of the data blocks is associated with a respective storage chip within a plurality of storage chips.

11. The method of claim 1, wherein the codeword is a logical block requested by a host device.

12. The method of claim 1, wherein the information related to the reliability of the each of the data blocks comprises information related to at least one of an erase cycle count for a data block or a program cycle count for a data block.

13. The method of claim 1, wherein the information related to the reliability of the each of the data blocks comprises information related to at least one of an amount of time to perform an erase operation for a data block and an amount of time to perform a program operation for a data block.

14. The method of claim 1, wherein the information related to the reliability of the each of the data blocks comprises information related to at least one of errors that occur with respect to a data block and an error log for a data block.

15. A method comprising:

retrieving a codeword from a plurality of data blocks within a storage device, wherein each of the data blocks stores a respective portion of the codeword;

performing codeword portion-specific error corrections on the portions of the codeword to generate codeword portion-specific error correction information; and

performing codeword-level error correction on the codeword based on the codeword-specific error correction information and information related to a reliability of each of the data blocks.

16. The method of claim 15, wherein each of the data blocks is associated with a respective storage chip within a plurality of storage chips.

17. A method comprising:

retrieving raw data bits for a codeword stored within a data block of a block storage device;

retrieving information related to a reliability of the data block, wherein the information related to the reliability of the data block comprises at least of an amount of time to perform an erase operation for the data block, an amount of time to perform a program operation for the data block, errors that occur with respect to the data block, and an error log for the data block;

generating soft detected values for the raw data bits based on soft information bits contained within the raw data values and information related to a reliability of the data block; and

performing error correction for the raw data bits based on the soft detected values.

18. The method of claim 17, wherein the soft detected values comprise log-likelihood ratios (LLR).

19. The method of claim 17, wherein the information related to the reliability of the each of the data blocks comprises information related to at least one of an amount of time to perform an erase operation for a data block and an amount of time to perform a program operation for a data block.

20. The method of claim 17, wherein the information related to the reliability of the each of the data blocks comprises information related to at least one of errors that occur with respect to a data block and an error log for a data block.

21-50. -50. (canceled)