[RFC,0/8] Add support for 10G Ethernet SerDes on MT7988

This series aims to add support for GMAC2 and GMAC3 of the MediaTek MT7988 SoC.
While the vendor SDK stuffs all this into their Ethernet driver, I've tried to
seperate things into a PHY driver, a PCS driver as well as changes to the
existing Ethernet and LynxI PCS driver.

                  +----------------+
+--------------+  |  USXGMII PCS   |   +------------------+
| Ethernet MAC +--+-------------+  +---+ PEXTP SerDes PHY |
+--------------+  |  SGMII PCS  |  |   +------------------+
                  +-------------+--+

Alltogether this allows using GMAC2 and GMAC3 with all possible interface modes,
including in-band-status if needed.

Daniel Golle (8):
  dt-bindings: phy: mediatek,xfi-pextp: add new bindings
  phy: add driver for MediaTek pextp 10GE SerDes PHY
  net: pcs: pcs-mtk-lynxi: use 2500Base-X without AN
  net: pcs: pcs-mtk-lynxi: allow calling with NULL advertising
  dt-bindings: net: pcs: add bindings for MediaTek USXGMII PCS
  net: pcs: add driver for MediaTek USXGMII PCS
  dt-bindings: net: mediatek,net: fix and complete mt7988-eth binding
  net: ethernet: mtk_eth_soc: add paths and SerDes modes for MT7988

 .../devicetree/bindings/net/mediatek,net.yaml | 171 ++++-
 .../bindings/net/pcs/mediatek,usxgmii.yaml    | 105 +++
 .../bindings/phy/mediatek,xfi-pextp.yaml      |  71 ++
 MAINTAINERS                                   |   3 +
 drivers/net/ethernet/mediatek/Kconfig         |  17 +
 drivers/net/ethernet/mediatek/mtk_eth_path.c  | 122 +++-
 drivers/net/ethernet/mediatek/mtk_eth_soc.c   | 178 ++++-
 drivers/net/ethernet/mediatek/mtk_eth_soc.h   | 105 ++-
 drivers/net/pcs/Kconfig                       |  10 +
 drivers/net/pcs/Makefile                      |   1 +
 drivers/net/pcs/pcs-mtk-lynxi.c               |  38 +-
 drivers/net/pcs/pcs-mtk-usxgmii.c             | 688 ++++++++++++++++++
 drivers/phy/mediatek/Kconfig                  |  11 +
 drivers/phy/mediatek/Makefile                 |   1 +
 drivers/phy/mediatek/phy-mtk-pextp.c          | 355 +++++++++
 include/linux/pcs/pcs-mtk-usxgmii.h           |  18 +
 16 files changed, 1813 insertions(+), 81 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/net/pcs/mediatek,usxgmii.yaml
 create mode 100644 Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.yaml
 create mode 100644 drivers/net/pcs/pcs-mtk-usxgmii.c
 create mode 100644 drivers/phy/mediatek/phy-mtk-pextp.c
 create mode 100644 include/linux/pcs/pcs-mtk-usxgmii.h

> +  mediatek,usxgmii-performance-errata:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      USXGMII0 on MT7988 suffers from a performance problem in 10GBase-R
> +      mode which needs a work-around in the driver. The work-around is
> +      enabled using this flag.

Is there more details about this? I'm just wondering if this should be
based on the compatible, rather than a bool property.

      Andrew

On Thu, 09 Nov 2023 21:50:55 +0000, Daniel Golle wrote:
> Add bindings for the MediaTek PEXTP Ethernet SerDes PHY found in the
> MediaTek MT7988 SoC which can operate at various interfaces modes:
> 
>  * USXGMII
>  * 10GBase-R
>  * 5GBase-R
>  * 2500Base-X
>  * 1000Base-X
>  * Cisco SGMII (MAC side)
> 
> Signed-off-by: Daniel Golle <daniel@makrotopia.org>
> ---
>  .../bindings/phy/mediatek,xfi-pextp.yaml      | 71 +++++++++++++++++++
>  1 file changed, 71 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.example.dts:18:18: fatal error: dt-bindings/clock/mediatek,mt7988-clk.h: No such file or directory
   18 |         #include <dt-bindings/clock/mediatek,mt7988-clk.h>
      |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
make[2]: *** [scripts/Makefile.lib:419: Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.example.dtb] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [/builds/robherring/dt-review-ci/linux/Makefile:1427: dt_binding_check] Error 2
make: *** [Makefile:234: __sub-make] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/924c2c6316e6d51a17423eded3a2c5c5bbf349d2.1699565880.git.daniel@makrotopia.org

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

On Thu, Nov 09, 2023 at 11:11:02PM +0000, Daniel Golle wrote:
> Hi Andrew,
> 
> On Thu, Nov 09, 2023 at 10:55:55PM +0100, Andrew Lunn wrote:
> > > +  mediatek,usxgmii-performance-errata:
> > > +    $ref: /schemas/types.yaml#/definitions/flag
> > > +    description:
> > > +      USXGMII0 on MT7988 suffers from a performance problem in 10GBase-R
> > > +      mode which needs a work-around in the driver. The work-around is
> > > +      enabled using this flag.
> > 
> > Is there more details about this? I'm just wondering if this should be
> > based on the compatible, rather than a bool property.
> 
> The vendor sources where this is coming from are here:
> 
> https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/a500d94cd47e279015ce22947e1ce396a7516598%5E%21/#F0
> 
> And I'm afraid this is as much detail as it gets. And yes, we could
> also base this on the compatible and just have two different ones for
> the two PEXTP instances found in MT7988.
> Let me know your conclusion in that regard.

I'd go with a property in this case unless you think there may be other 
per instance differences.

Rob