How many lanes are in each minipci slot?

Banana Pi Router design BPI-R4/BPI-R4 Pro(MT7988)
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Documentation:

  • 2x miniPCIe slots with PCIe3.0 2lane interface for Wi-Fi NIC

Where real lane is one minipci slot?

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Hi，

There are 2 lanes in total. The standard minipcie socket only has 1 lane pcie. BPI-R4 uses 4 additional PINs as the second line, which is not standard.

1 Like
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You mean per mpcie socket 2 lanes,right? One per standard and then the 4 additional pins for second…so total of 4 (both slots).

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In real-world usage, roughly equivalent to PCIe 3.0 x0.6.

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Thanks for the answers. I was interested in this question in connection with the choice of a minipci - pcie adapter.

Where can I find a pinout diagram for mini pci BPI-R4 with extra 4 pin lanes?

There may be recommendations for a common PCIE adapter that does not require modification.

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https://wiki.banana-pi.org/Banana_Pi_BPI-R4#Documents

“BPI-R4 Schematic diagram” should be a good place to start

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Continuing on the topic:

Do you need to edit .dts/.dtsi files if you want to route 4 lanes from two minipci slots to one PCIEx4 port (adapter)?

Or correct the values ​​in pinctrl-mt7988.c accordingly = mt7988_pcie_*_n3_0_pins,mt7988_pcie_*_n3_0_funcs should be moved to mt7988_pcie_*_n0_0_* or mt7988_pcie_*_n0_1_*, am I right?

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Dts describe hardware,i think you cannot change it here…but information should be in shematic.

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Schematically, it is necessary to remove one minipci slot from the system, and transfer the resources - 2 lanes to the neighboring minipci slot. Since the “unnecessary” minipci slot is initialized at startup, and this will always cause errors.

I do not understand the .dts format well, especially the origin of variable names - where they are initially described. This needs to be sorted out.