Re: [PATCH v5 0/2] PCI: mediatek-gen3: Add 2-lanes mode support + clock

On Fri, Aug 7, 2026 at 12:53 AM Christian Marangi <[email protected]> wrote:
> This small series introduce support for 2-lanes mode for Airoha AN7581

Just a nitpick, but I would probably name this something else, like
"cross-controller lane-bonding mode" or "lane stealing"? PCIe already
has 2x lanes as a standard feature, so this naming is a bit confusing.
It's not like dual-LVDS display in which LVDS is only a single lane.


ChenYu

> SoC. This is needed for correctly functionality of Eagle WiFi Card
> normally attached to this SoC that require a 2-line PCIe card to
> correctly work (and give the proper performance)
>
> The first 2 patch address a limitation of the PCIe implementation
> where the PERSTOUT reset were indirectly asserted and deasserted
> all at the same time (for all the 3 PCIe card) with PCIe
> enable and disable.
> The 2 patch address this and introduce correct reset to control
> reset line for the relevant PCIe line.
>
> The last 2 patch add additional logic and support to assert
> and deassert the PERSTOUT and also apply the required configuration
> for 2-lanes mode.
>
> 2-lanes mode is implemented in DT by adding the required property
> and by defining the "num-lanes" to 2.
>
> Changes v5:
> - Address formal comments from Bjorn
> - Drop clk patch (handled in separate series)
> - Add reference to clk changes
> Changes v4:
> - Improve DT split patch (drop unneeded property)
> - Handle power_down PERSTOUT
> Changes v3:
> - Add Ack from Krzysztof
> - Improve commit description of PCIe patch
> - Use pcie->num_lanes instead of possible uninit variable num_lanes
> Changes v2:
> - Address typo regs -> reg in Documentation
> - Address typo lan -> lane in Documentation
> - Apply a suggested fix from Airoha for PCIe MUX configuration
>   before PHY init
> - Parse secondary reg in probe
> - Add missing reset_status handling for inverted bits
> - Move SCU to local handling in power_up
> - Add check for max num-lanes for EN7581
>
> Christian Marangi (2):
>   dt-bindings: PCI: mediatek-gen3: Split Airoha schema and document
>     2-lanes
>   PCI: mediatek-gen3: Add 2-lanes mode support for Airoha AN7581
>
>  .../bindings/pci/airoha,en7581-pcie.yaml      | 244 ++++++++++++++++++
>  .../bindings/pci/mediatek-pcie-gen3.yaml      |  77 +-----
>  drivers/pci/controller/pcie-mediatek-gen3.c   | 106 ++++++--
>  3 files changed, 338 insertions(+), 89 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/pci/airoha,en7581-pcie.yaml
>
> --
> 2.53.0
>
>