[U-Boot-Users] flash driver in u-boot

I'm a little confused by flash driver selection in u-boot. My flash device is intel JS28F128J3, I assume it's not CFI flash so I want to use strataflash.c. I added such file under my board directory, add it into Makefile, and undef CFG_FLASH_CFI_DRIVER, but I got link error. If define this macro, the compilation is ok and my flash works. My question is, if we define this macro, which flash driver being used? cfi_flash.c or my strataflash.c?

I'll appreciate if someone can shed some lights.

- Reeve