Codeword management

• US 9,524,211 B1
• Filed: 11/18/2014
• Issued: 12/20/2016
• Est. Priority Date: 11/18/2014
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Segal, Avigdor, Weingarten, Hanan, Maly, Igal
• Primary Examiner(s): Alphonse, Fritz
• Application Number:
  US14/547,008
• Time in Patent Office: 763 Days
• Field of Search: 714/767, 714/784
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1072 in multilevel memories
• CPC Class Codes: G11C 29/18 Address generation devices; Devices for accessing memories, e.g. details of addressing circuits
• CPC Class Codes: G11C 29/36 Data generation devices, e.g. data inverters
• CPC Class Codes: G11C 29/42 using error correcting codes [ECC] or parity check
• CPC Class Codes: G11C 29/52 Protection of memory contents; Detection of errors in memory contents

Abstract

A method for managing an encoding process, the method includes receiving or determining, by a processor, (i) code rates for multiple pages, and (ii) sizes of a plurality of data segments to be stored in the multiple pages after being encoded to provide multiple codewords; determining, by the processor, sizes of the multiple codewords while maintaining the code rates for the multiple pages and minimizing a number of split data segments out of the plurality of data segments, wherein each split data segment is split between at least two codewords of the multiple codewords, wherein a retrieval of the split data segment involves a retrieval of the at least two codewords; and sending to an encoder information about the sizes of the multiple codewords.

Claims

1. A method for managing an encoding process, the method comprises:

receiving or determining, by a processor, (i) code rates for multiple pages of a flash memory, and (ii) sizes of a plurality of data segments to be stored in the multiple pages after being encoded to provide multiple codewords;

determining, by the processor, sizes of the multiple codewords while maintaining the code rates for the multiple pages and minimizing a number of split data segments out of the plurality of data segments, wherein each split data segment is split between at least two codewords of the multiple codewords, wherein a retrieval, from the flash memory, of each split data segment that is stored in the flash memory and is split between the at least two codewords involves a retrieval of the at least two codewords; and

sending to an encoder information about the sizes of the multiple codewords.

2. The method according to claim 1 further comprising receiving or determining, by the processor a flash memory transaction size;

and wherein the determining of the sizes of the multiple codewords is further responsive to the flash memory transaction size.

3. The method according to claim 1, comprising determining the sizes of multiple codewords to minimize a number of codewords that comprise at least a portion of two data segments.

4. The method according to claim 1, comprising determining the sizes of the multiple codewords so that at least one page of the multiple pages comprises codewords that differ from each other by a size of redundancy.

5. The method according to claim 1, comprising determining the sizes of multiple codewords to allow only up to a single codeword per page to comprise at least a portion of two data segments.

6. The method according to claim 1, wherein the code rates for the multiple pages comprise a first code rate that is higher than a second code rate;

wherein the first code rate is associated with a first page of the multiple pages and the second code rate is associated with a second page of the multiple pages.

7. The method according to claim 6 comprising preventing the second page from storing a codeword that comprises at least a portion of two data segments.

8. The method according to claim 6 wherein at least one codeword of the first page comprises at least a portion of two data segments.

9. The method according to claim 1 further comprising receiving the plurality of data segment and encoding the plurality of data segments to provide the multiple codewords, wherein the encoding is responsive to the information about the sizes of the multiple codewords.

10. A method for encoding data segments, the method comprises:

receiving, by an encoder, information about sizes of multiple codewords to be generated by the encoder by encoding a plurality of codewords;

wherein the sizes of the multiple codewords were determined (a) in response to code rates for multiple pages of a flash memory and sizes of the plurality of data segments, and (b) while maintaining the code rates for the multiple pages and minimizing a number of split data segments out of the plurality of data segments, wherein each split data segment is split between at least two codewords of the multiple codewords, wherein a retrieval, from the flash memory, of each split data segment that is stored in the flash memory and is split between the at least two codewords involves a retrieval of the at least two codewords;

receiving, by the encoder, the plurality of data segment; and

encoding, by the encoder, the plurality of data segments to provide the multiple codewords, wherein the encoding is responsive to the information about the sizes of the multiple codewords.

11. A non-transitory computer readable medium that stores instructions that once executed by an encoder cause the encoder to execute the stages of:

receiving information about sizes of multiple codewords to be generated by the encoder by encoding a plurality of codewords;

wherein the sizes of the multiple codewords were determined (a) in response to code rates for multiple pages of a flash memory and sizes of the plurality of data segments, and (b) while maintaining the code rates for the multiple pages and minimizing a number of split data segments out of the plurality of data segments, wherein each split data segment is split between at least two codewords of the multiple codewords, wherein a retrieval, from the flash memory, of each split data segment that is stored in the flash memory and is split between the at least two codewords involves a retrieval of the at least two codewords;

receiving the plurality of data segment; and

encoding the plurality of data segments to provide the multiple codewords, wherein the encoding is responsive to the information about the sizes of the multiple codewords.

12. The non-transitory computer readable medium according to claim 11 that stores instructions for receiving or determining, by the processor a flash memory transaction size;

and wherein the determining of the sizes of the multiple codewords is further responsive to the flash memory transaction size.

13. The non-transitory computer readable medium according to claim 11, that stores instructions for determining the sizes of multiple codewords to minimize a number of codewords that comprise at least a portion of two data segments.

14. The non-transitory computer readable medium according to claim 11, that stores instructions for determining the sizes of the multiple codewords so that at least one page of the multiple pages comprises codewords that differ from each other by a size of redundancy.

15. The non-transitory computer readable medium according to claim 11, that stores instructions for determining the sizes of multiple codewords to allow only up to a single codeword per page to comprise at least a portion of two data segments.

16. The non-transitory computer readable medium according to claim 11, wherein the code rates for the multiple pages comprise a first code rate that is higher than a second code rate;

wherein the first code rate is associated with a first page of the multiple pages and the second code rate is associated with a second page of the multiple pages.

17. The non-transitory computer readable medium according to claim 16 that stores instructions for preventing the second page from storing a codeword that comprises at least a portion of two data segments.

18. The non-transitory computer readable medium according to claim 16 wherein at least one codeword of the first page comprises at least a portion of two data segments.

19. The non-transitory computer readable medium according to claim 11 that stores instructions for receiving the plurality of data segment and encoding the plurality of data segments to provide the multiple codewords, wherein the encoding is responsive to the information about the sizes of the multiple codewords.

20. A non-transitory computer readable medium that stores instructions that once executed by a processor cause the processor to execute the stage of receiving or determining (i) code rates for multiple pages of a flash memory, and (ii) sizes of a plurality of data segments to be stored in the multiple pages after being encoded to provide multiple codewords;

determining sizes of the multiple codewords while maintaining the code rates for the multiple pages and minimizing a number of split data segments out of the plurality of data segments, wherein each split data segment is split between at least two codewords of the multiple codewords, wherein a retrieval, from the flash memory, of each split data segment that is stored in the flash memory and is split between the at least two codewords involves a retrieval of the at least two codewords; and

sending to an encoder information about the sizes of the multiple codewords.

21. A memory controller that comprises an encoder;

wherein the encoder is configured to;

receive information about sizes of multiple codewords to be generated by the encoder by encoding a plurality of codewords;

wherein the sizes of the multiple codewords were determined (a) in response to code rates for multiple pages of a flash memory and sizes of the plurality of data segments, and (b) while maintaining the code rates for the multiple pages and minimizing a number of split data segments out of the plurality of data segments, wherein each split data segment is split between at least two codewords of the multiple codewords, wherein a retrieval, from the flash memory, of each split data segment that is stored in the flash memory and is split between the at least two codewords involves a retrieval of the at least two codewords;

receive the plurality of data segment; and

encode the plurality of data segments to provide the multiple codewords, wherein the encoding is responsive to the information about the sizes of the multiple codewords.