I am currently using the Evaluation Module for the AM389x and looking specifically at the PCIe Subsystem.
When trying to connect more than a dozen End Point PCIe devices with the help of PCIe Switches, I am not able to meet the Memory Address Space requirements of all the End Point devices. In the Technical Reference Manual for this Sitara part (AM389x_Sitara_TRM_1_July_2011), under Section 17.2.4 Address Spaces (Peripheral Component Interconnect Express PCIe), it eludes to having a Hardware configurable register setting maximum capability of only 256 MB of Outbound memory if using all 32 Region’s configured for 8MB size. Is there anything that can increase this address space limitation? Is this also stating that you can hook up a maximum of 32 End Point Devices to the AM389x set for Root Complex mode?
I have looked at the TI816x-PSP-PCIe-RC-Driver-User-Guide PDF and it also mentions a RC Driver Outbound Memory assignment of 0x20000000-0x2FFFFFFF (256MB). I’m a little unclear if this can be increased in the driver or not, but looking at the 32 Region registers it would appear this is a HW limited resource on the PCIe Outbound Memory. Would like a confirmation on this one way or another.
Thanks!
