AM5728: PCI-host RAM memory access from PCIe device

Hi!

We're working with custom AM5728 board running QNX 6.5 OS. Board has two PCIe Intel I210 network controllers.

PCie host controller is configured, link is up, I210 controllers are enumerated and present on the PCI bus, ATU is configured, PCIe device configuration space and BARs access is configured and working, device is configured, up and running.

The problem is that PCIe device (i210) can't write data directly to AM5728 RAM memory through PCIe bus. Can you please advice what could possible be wrong and prevent writes to PCI-host RAM memory?

Thanks!