[PATCH v5 0/2] Add i.MX8Q HSIO PHY support

[Richard Zhu]

v5 changes:
dt-binding
- Fix dt_binding_check errors of fsl,refclk-pad-mode.
  And, add the unused description of this property.
- Add description for each register entry.
- Add fsl,hsio-cfg description.
- Other minor refine changes.

PHY driver
- To make codes safe enough in multi instances probe, use scoped_guard()
to replace the atomic_###() callbacks.

v4:https://patchwork.kernel.org/project/linux-phy/cover/1715234181-672-1-git-send-email-hongxing.zhu@nxp.com/

v4 changes:
- Re-format the "phy-cells" as <&hsio_phy lane_id phy_mode controller_id>
- Use each lane as a phys entry, suggested by Rob.
PCIEA:
phys = <&hsio_phy 0 PHY_MODE_PCIE>;
or:
phys = <&hsio_phy 0 PHY_MODE_PCIE>, <&hsio_phy 1 PHY_MODE_PCIE>;

PCIEB:
phys = <&hsio_phy 1 PHY_MODE_PCIE>;
or:
phys = <&hsio_phy 2 PHY_MODE_PCIE>;

SATA:
phys = <&hsio_phy 2 PHY_MODE_SATA>;

- Add a new propery "fsl,hsio-cfg".
The HSIO configuration (fsl,hsio-cfg) is one global state.
It should be known and used to set global setting: PCIE_AB_SELECT and
PHY_X1_EPCS_SEL at the begin of HSIO initialization like this listed below.

 +-------------------------------------------------------------+
 |CRR(SYS.CSR) register|PCIAx2 and|PCIEAx1, PCIEBx1|PCIEAx2 and|
 |                     |SATA      |SATA            |PCIEBx1    |
 |---------------------|----------|----------------|-----------|
 |PCIE_AB_SELECT       | 0        | 1              | 1         |
 |---------------------|----------|----------------|-----------|
 |PHY_X1_EPCS_SEL      | 1        | 1              | 0         |
 +-------------------------------------------------------------+
When first PHY instance is probed, PHY driver can't get a global view of the
HSIO use case and doesn't know how to set global setting: PCIE_AB_SELECT and
PHYX1_EPCS_SEL.
Because first PHY instance doesn't know followed PHY instance use mode.

So, one property named "fsl,hsio-cfg" has to be introduced here to specify the
setting of the global setting: PCIE_AB_SELECT and PHY_X1_EPCS_SEL.

Here is the discussion about this.
https://lkml.org/lkml/2024/4/26/231

- Address Conor's comments about the "fsl,refclk-pad-mode".
fsl,refclk-pad-mode:
  description:
    ...
  enum: ["input", "output"].

v3:https://patchwork.kernel.org/project/linux-phy/cover/1713939683-15328-1-git-send-email-hongxing.zhu@nxp.com/

v3 changes:
Refer to Conor's comments.
- Let filename match a compatible
- Refine description of the fsl,refclk-pad-mode.
- Remove power-domains description.
- Keep clock ording for two devices.
- Drop the unused label and status.
Refer to Rob's comments.
- Use standard phy mode defines.
- Correct the spell mistakes in the binding document.

v2:https://patchwork.kernel.org/project/linux-phy/cover/1712036704-21064-1-git-send-email-hongxing.zhu@nxp.com/ 

v2 changes:
- Place the dt-bindings header file changes as the first one
in the patch-set, make the annotation more clear, and add
Frank's Reviewed-by tag.

v1:https://patchwork.kernel.org/project/linux-phy/cover/1711699790-16494-1-git-send-email-hongxing.zhu@nxp.com/

[PATCH v5 1/2] dt-bindings: phy: Add i.MX8Q HSIO SerDes PHY binding
[PATCH v5 2/2] phy: freescale: imx8qm-hsio: Add i.MX8QM HSIO PHY

Documentation/devicetree/bindings/phy/fsl,imx8qm-hsio.yaml | 152 +++++++++++++++++++++
drivers/phy/freescale/Kconfig                              |   8 ++
drivers/phy/freescale/Makefile                             |   1 +
drivers/phy/freescale/phy-fsl-imx8qm-hsio.c                | 608 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
include/dt-bindings/phy/phy-imx8-pcie.h                    |  29 ++++
5 files changed, 798 insertions(+)