Unable to mount LittleFS on larger flash memory

[kotalamit]

Hi,

I am using the IMXRT1172xx microcontroller for our Proto. In that we plan to use LittleFS along with the application code running in the Ext. flash of 64MB.

For testing purpose, I was successfully able to run the LittleFS Example code provided in the SDK, wherein I had moved the fsl_flexspi.o and mflash_drv.o files to RAM using Initialize by copy in Linker. Based on this things function as required and I am able to mount the file system at any block address less than 16MB. 

Similarly, if I try to the same considering 64MB as Flash size, I try to mount it at 16MB (0x1000000) or further, it is able to format and mount/unmount/create dir etc successfully, but once the code seems to be blocked and not running.

Points to be noted, 

IDE used : IAR.

Debugger : Jlink.

Additionally, to accommodate for the 64MB flash, I had changed the #define BOARD_FLASH_SIZE (0x4000000U) in board.h file and the qspiflash_config.memConfig.sflashA1Size = 64u * 1024u * 1024u in evkmimxrt1170_flexspi_nor_config.c file.

Any insight and support will be very much helpful.

Regards,

Amit Kotal

[Omar_Anguiano]

Hello
I hope you are well.

I suggest you execute all of your code on RAM, not just the flash drivers, and reserve the code so that space is not added to your file system.

Best regards,
Omar

[kotalamit]

Hi Omar,

Thanks for the suggestion, unfortunately the product design requirement mandates the code to be running from Flash in XIP mode. Although I am not able to understand, if running only the flash driver from RAM works for a Smaller 16MB flash, then what can be the issue with a larger 64MB Flash??

Also can you elaborate what you mean by "so that space is not added to your file system".

Regards,

Amit Kotal

[Omar_Anguiano]

It will be important to check the partition. It is important that the boot area is totally separated from the data area. It is probable that XIP is colliding with the access to the flash-through.
For testing proposes, is it possible to execute your code to ram to check if the issue is still present?

Best regards,
Omar

[kotalamit]

Hi Omar,

Further quick support/response will be very much helpful. We are running on a tight schedule and need to take a final call asap.

As of now it seems to be some sdk bug where in the XIP + littlefs is only supported for flash memory only upto 16MB.

Regards,

Amit Kotal