dma-coherent property for PCIe Root

[Valmiki]

Hi All,

How does "dma-coherent" property will work for PCIe as RC on an
ARM SOC ?
Because the end point device drivers are the one which will request dma 
buffers and Root port driver doesn't involve in data path of end point
except for handling interrupts.

How does EP DMA buffers will be hardware coherent if RC driver exposes
dma-coherent property ?

Regards,
Valmiki