PROCESSOR-SDK-AM62X: NAND problem,GPMC address space is 1GB ,but can work on the nand flash of 2GB ,

Hello Helen Han,

Thank you for the query.

The addressing schemes are different.

Please refer below for info related to nand flash.

https://user.eng.umd.edu/~blj/CS-590.26/micron-tn2919.pdf

Regards,

Sreenivasa

Hi， I  want to know the max space address for GPMC interface. does it support for 16GB NAND ?

Hello Helen Han,

Helen Han said:

I  want to know the max space address for GPMC interface. does it support for 16GB NAND ?

Could you please help us understand the use case.

Regards,

Sreenivasa

HI , we find GPMC in the AM62X  datasheet. its main features  supports  in a total address space of 1GB.  but now we have used a 2GB(2048Mbytes) nand flash . the linux system runs well .we want to know how it works? because the nand address 2GBytes  exceeds the 1GB address space .

Hello Helen Han,

The 1GB (this is 128 MB)  is memory mapped.

NAND memory is a block device and it's not directly addressable by the GPMC address pins. The data pins are used as address pins allowing the SoC to access larger NAND flash.

Please read below section of TRM. 

12.4.3 General-Purpose Memory Controller (GPMC)

Regards,

Sreenivasa

Hi Sreenivasa,

How 128MB memory map to 1GB?

Best Regards,

Zane

Hello Zane Wei,

NAND memory is a block device and it's not directly addressable by the GPMC address pins. 

Regards,

Sreenivasa