DEVICE AND METHOD FOR MANAGING INITIALIZATION THEREOF

• US 20090172246A1
• Filed: 12/26/2007
• Published: 07/02/2009
• Est. Priority Date: 12/26/2007
• Status: Abandoned Application

• Current Assignee: SanDisk IL Ltd. (Western Digital Corporation)
• Original Assignee: SanDisk IL Ltd. (Western Digital Corporation)
• Inventors: Afriat, Itshak
• Application Number:
  US11/964,057
• Publication Number:
  US 20090172246A1
• Time in Patent Office: Days
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers

Abstract

A host may initialize itself faster by enabling an associated storage device to respond to host access commands under specified conditions before the storage device has completed its own initialization. Embodiments of the invention include a storage device, a controller, a method of servicing commands, and a method of using a host that sends access commands to a storage device. Access commands to a flash memory use logical addresses to reference the memory contents. A controller translates the logical addresses to physical addresses using a mapping table that the controller constructs in volatile memory during initialization based on data retrieved from the flash memory. An access command satisfying a predefined condition is serviced before the controller completes the construction of the mapping table.

Claims

11. A controller for controlling a storage device, the controller comprising:

a volatile memory; and

logic circuitry configured to receive a command with a logical address and to translate the logical address to a physical address using a mapping table, which mapping table is constructed in the volatile memory during initialization based on data that the logic circuitry retrieves from a flash memory,

wherein the logic circuitry is operative to service an access command before completing the construction of the mapping tables if the access command includes a logical address that satisfies a predefined condition.

12. The controller of claim 11, wherein the initialization occurs during a power-up or a reset operation.

13. The controller of claim 12, wherein the initialization occurs during a reset operation, and the reset operation is a hardware or a software reset operation.

14. The controller of claim 11, wherein the access command is a read command.

15. The controller of claim 14, wherein the read command is from a host, and the logic circuitry is operative to respond to the read command by transferring code from the flash memory to the host, which uses the code for initialization of the host.

16. The controller of claim 11, wherein the logic circuitry is further operative to disregard an access command, which does not include a logical address satisfying the predefined condition, if the construction of the mapping table has not yet completed.

17. The controller of claim 11, wherein the logic circuitry is further operative to delay servicing an access command, which does not include a logical address satisfying the predefined condition, until after completing the construction of the mapping table.

18. The controller of claim 11, wherein the logical address satisfies the predefined condition if the logical address equals one of a set of one or more logical addresses.

19. The controller of claim 18, wherein the access command satisfies a predefined condition if the at least one logical address is within a predefined range.

20. The controller of claim 19, wherein the predefined range includes logical address zero.

21. A method of servicing commands that use logical addresses, the method comprising:

providing a controller operative to

service commands that use logical addresses to reference contents of a flash memory, and

translate logical addresses to physical addresses, which translation uses at least one mapping table that the controller constructs in volatile memory during initialization based on data retrieved from the flash memory;

providing to the controller a command that includes a logical address, which address satisfies a predefined condition; and

causing the controller, in response thereto, to service the command before the controller completes the construction of the at least one mapping table.

22. The method of claim 21, wherein the initialization occurs during a power-up or a reset operation.

23. The method of claim 22, wherein the initialization occurs during a reset operation, and the reset operation is a hardware or a software reset operation.

24. The method of claim 21, wherein the command provided to the controller is a read command.

25. The method of claim 24, wherein the read command provided to the controller is from a host, the method further comprising:

causing the controller to respond to the read command by transferring code from the flash memory to the host, which uses the code for initialization of the host.

26. The method of claim 21, further comprising:

causing the controller to disregard an access command, which does not include a logical address satisfying the predefined condition, if the construction of the mapping table has not yet completed.

27. The method of claim 21, further comprising:

causing the controller to delay servicing an access command, which does not include a logical address satisfying the predefined condition, until after completing the construction of the mapping table.

28. The method of claim 21, wherein the logical address satisfies the predefined condition if the logical address equals one of a set of one or more logical addresses.

29-1. The method of claim 38, wherein the command provided to the controller satisfies a predefined condition if the at least one logical address is within a predefined range.

31. A method of using a host that sends access commands to a storage device, the access commands using logical addresses, the method comprising:

providing a storage device with a controller, the controller being operative to

service commands that use logical addresses to reference contents of a flash memory, and

translate logical addresses to physical addresses, which translating uses at least one mapping table that the controller constructs in volatile memory during initialization based on data retrieved from the flash memory;

transferring from a host to the controller a command that includes a logical address, which address satisfies a predefined condition; and

causing the controller, in response thereto, to service the command before the controller completes the construction of the at least one mapping table.

1. A storage device for servicing commands that use logical addresses to reference memory contents, the storage device comprising:

a flash memory; and

a controller configured to translate a logical address in a command to a physical address using a mapping table that the controller constructs in volatile memory during initialization based on data retrieved from the flash memory,

wherein the controller is operative to service an access command before the controller completes the construction of the mapping table, the access command including a logical address satisfying a predefined condition.

2. The storage device of claim 1, wherein the initialization occurs during a power-up or a reset operation.

3. The storage device of claim 2, wherein the initialization occurs during a reset operation, and the reset operation is a hardware or a software reset operation.

4. The storage device of claim 1, wherein the access command is a read command.

5. The storage device of claim 4, wherein the read command is from a host, and the controller is operative to respond to the read command by transferring code from the flash memory to the host, which uses the code for initialization of the host.

6. The storage device of claim 1, wherein the controller is further operative to disregard an access command, which does not include a logical address satisfying the predefined condition, if the construction of the mapping table has not yet completed.

7. The storage device of claim 1, wherein the controller is further operative to delay servicing an access command, which does not include a logical address satisfying the predefined condition, until after completing the construction of the mapping table.

8. The storage device of claim 1, wherein the logical address satisfies the predefined condition if the logical address equals one of a set of one or more logical addresses.

9. The storage device of claim 8, wherein the access command satisfies the predefined condition if the at least one logical address is within a predefined range.

10. The storage device of claim 9, wherein the predefined range includes logical address zero.

29. The method of claim 28, wherein the command provided to the controller satisfies a predefined condition if the at least one logical address is within a predefined range.

30. The method of claim 29, wherein the predefined range includes logical address zero.

32. The method of claim 31, wherein the initialization occurs during a power-up or a reset operation.

33. The method of claim 32, wherein the initialization occurs during a reset operation, and the reset operation is a hardware or a software reset operation.

34. The method of claim 31, wherein the command provided to the controller is a read command.

35. The method of claim 34 further comprising:

causing the controller to respond to the read command by transferring code from the flash memory to the host, which uses the code for initialization of the host.

36. The method of claim 31, further comprising:

causing the controller to disregard an access command, which does not include a logical address satisfying the predefined condition, if the construction of the mapping table has not yet completed.

37. The method of claim 31, further comprising:

causing the controller to delay servicing an access command, which does not include a logical address satisfying the predefined condition, until after completing the construction of the mapping table.

38. The method of claim 31, wherein the logical address satisfies the predefined condition if the logical address equals one of a set of one or more logical addresses.

40. The method of claim 39, wherein the predefined range includes logical address zero.