reading a data through address in embedded linux kernel

[mashhur]

hello guys,

im lil bit confusing on memories and ganna ask some tricks.
when we wanna write some data to a RAM address, let's say we have an "ABC" value for "0xABCD" address, we could write smth like this code:

// in C, linux kerenel
#define ADDRESS 0xABCD
char *data = "ABC";
char *addr = (char*)ADDRESS;
addr = data;

now the problem is for me how to write this data to other memories, let's say NAND memory or other external memories.

I heard that there are physical and virtual memories. could somebody pls explain them? And the issue below could be solved by "chip select address" said one engineer. is it whether true? how to implement it??

thanks for helping out.

 

[skogsjanne]

Maybe this is of some help:
Direct Memory Access in Linux - Stack Overflow