PCIe x4 + x1

Autonomous Machines Jetson & Embedded Systems Jetson TK1
#1

Hi all,

Regarding TRM p2360 section 32.4.21 in the AFI PCIe config, we can read that it is possible to configure the TK1 with PCIe x4 + x1.

Same thing still in the TRM p2261 in the section 32.0 on the figure 119 we can see the PCIe controller has 5 lanes and seems to support PCIe x4 + x1.

However in the datasheet p62, it’s stated “K1 series processors integrate a x4 lane PCIe bridge to enable a control path from the Tegra chip to external PCIe devices”.

So it is confusing if this configuration could be used on our custom board.

Best regards,
Alejuventino

#2

Yes, TK1 supports PCIe x4 + x1 configuration, we successfully used it on our custom board.

#3

Okay great !

And what are the steps you’ve used in the DTS and XUSB_PADCTL configurations ?
What slow IOs did you wire ? (RST, CLKREQ, WAKE…)

Regards,
alejuventino

#4

codebase has support for x4 and x1 and it should work out of the box given Tx,Rx,RST,REFCLK lanes routing in your custom board is proper.

#5

Is the issue you are seeing in u-boot or kernel?
Can you share your schematic?
Logs?

#6

https://devtalk.nvidia.com/default/topic/898775/how-to-use-pcie-x4-of-tk1-/

It is easy to do the change.