MPU config and memory attributes

I want config STM32F746 MPU ,

In the ARM Cortex M7 generic user guide External RAM memory region (0x60000000 - 0x7FFFFFFF)(512MByte) has WBWA (write back write allocate) cache policy see this link

http://infocenter.arm.com/hel...

But in a application note of STmicroelectronics Company (for stm32f7 and stm32h7) for MPU programming define this region as write-through for FMC peripheral

Nom ,which of these is true ???