Re: [U-Boot] [PATCH v2 20/21] cmd: mtd: add 'mtd' command

Hi Boris,

...

...

• if (full_erase) {
  

• 	off = 0;
  

• 	len = mtd->size;
  

• }
  

• if ((u32)off % mtd->erasesize) {    
  

Sounds dangerous. We have 8GB NANDs on sunxi platforms...

[...]

...

...

• if ((u32)len % mtd->erasesize) {    
  

Same here. I guess there's a do_div() in uboot.

In both cases I take the less significant bytes of a 64-bit value. The modulo operation is safe as long as mtd->erasesize is a 32-bit value too. I don't think there is any danger?

As discussed out of this thread, this works because mtd->erasesize is always a power of 2. Erase sizes not being a power of 2 do not exist but it will be safer to switch to do_div().

Thanks, Miquèl