Original question:
AM5708: Recommended differential trace impedance for PCIe Gen2 and Gen3 of AM5708
I am using PCIe Interface of AM5706 (Gen 2.0). AM5706 will be root-complex and it will be configured as x1 lane of 2 ports. Whether this mode is compatible?
From Datasheet , I came to know it won't support both ports at Gen2.0, one will be as Gen1.0 (RC) and other port will be configured as Gen2.0(RC). Is it correct?
Two PCIe (PCIe_SS1 and PCIe_SS2) operates Gen2 1-lane supporting either RC or EP with the possibility of one operating in Gen1 and one in Gen2 - From Datasheet
Hi Manikandan,
Yes, AM5706 should be configurable as root-complex for 2x 1 lane ports.
I am not aware of a limitation where one port needs to be at Gen1.0 speeds when configuring two single lane ports. In a different location of the datasheet we also say the following:
The intention of the line "with the possibility of one operating in Gen1 and one in Gen2" seems to be more for highlighting the feature of being able to configure each lane at different speeds. I will check internally to verify this statement, but please let us know if you are having issues with configuring both ports at Gen2.0 speeds.
Regards,
Takuma
From data manual title page:
Typically PCIe ports will support up to Gen-something, and that includes support for all the lower Gen/slower speeds.
